AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TALLAHASSEE FL 925 PM EDT FRI OCT 7 2005 .SYNOPSIS... 00Z SURFACE PLOT SHOWED THE COLD FRONT JUST E OF AN ALBANY GA TO DESTIN FL LINE. RADAR SHOWED SCATTERED SHOWERS TRYING TO KEEP ALIVE ALONG THE FRONT GENERALLY SW OF MARIANNA OUT INTO THE COASTAL WATERS. SOMEWHAT MORE ORGANIZED SHRA/TSRA CONTINUE E OF ALBANY...LIKELY THANKS TO GOOD DPVA ALOFT AHEAD OF THE WELL DEFINED UPPER VORT MAX OVER THE WRN FL PANHANDLE. THE 08/00Z TAE SOUNDING WAS STILL VERY WET AT 2.25" PWAT...BUT THERE IS EVIDENCE OF LARGE SCALE LIFT...AS LAPSE RATES HAD STEEPENED TO PROVIDE UNMODIFIED CAPES AROUND 2800 J/KG. && .SHORT TERM (TONIGHT)... MADE ADJUSTMENTS FOR MORE PESSIMISTIC SKY COVER...ESPECIALLY BEHIND THE FRONT. LOWERED POPS SLIGHTLY FOR MOST AREAS BASED ON CURRENT RADAR PRESENTATION. EXPECT ACTIVITY OVER OUR NE CWFA WILL BE SHORT LIVED AS THE VORT MAX EJECTS NE. && .MARINE... LOADED LATEST RUC WINDS...WHICH STILL KEEP OUR FAR WRN WATERS AROUND 15 KT BY DAYBREAK. SPEED AND LIMITED DURATION OF STRONGER WINDS SHOULD KEEP SEAS FROM REACHING SCEC LEVELS. THUS...NO HIGHLIGHTS ARE ANTICIPATED. && .AVIATION... REMNANT SHOWERS LEFT OVER FROM EVENING CONVECTION WILL DISSIPATE AROUND ABY BY 02Z. VLD COULD SEE 1-2 HOURS OF TSRA IN THE VICINITY. OVERNIGHT, WE SHOW MVFR CIGS DEVELOPING AT ALL TERMINALS BETWEEN 06-08Z, WITH IFR CONDITIONS PREVAILING AT DHN. IFR CIGS AND MVFR VSBYS WERE INCLUDED IN TEMPO GROUPS AFTER 08Z AT ABY, VLD, AND TLH, BEHIND THE FRONT. CIGS SHOULD LIFT TO VFR BY MID AFTERNOON SAT BEFORE CLOUDS SCATTER OUT DURING THE 2ND 1/2 OF THE AFTERNOON. THIS IS BASED ON THE GFS SOLUTION. && .TAE WATCHES/WARNINGS/ADVISORIES... AL...NONE. GA...NONE. FL...NONE. && $$ PUBLIC/MARINE...TJT AVIATION...MAW fl AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MELBOURNE FL 1030 AM EDT FRI OCT 7 2005 .DISCUSSION... ...HIGH RAIN CHANCES WITH LOCALLY HEAVY RAIN TODAY... CURRENT...SFC OBS/SAT IMAGERY SHOW BROAD DEEP LAYER LOW CONTINUING TO SPIN OVER THE ERN GOMEX. ON THE EAST SIDE OF THIS LOW...DEEP SOUTHERLY FLOW CONTINUES TO FEED SOUPY TROPICAL AIR MASS NWD ACROSS FL. MEAN PWATS THIS MORNING WERE GENERALLY A TENTH EITHER SIDE OF 2.4". MULTI-LAYERED CLDS RESULTING IN A BKN-OVC CONDS AREAWIDE. 88D MOSAIC SHOWS SCT LGT-MDT SHRA EXTENDING ALL THE WAY FROM AL/GA SWD THROUGH PENINSULAR FL ALL THE WAY TO (AND SOUTH OF) THE KEYS/STRAITS. LOOKING WWD OVER THE GOMEX...WATER VAPOR IMAGERY/RUC UPPER RH FIELDS SHOW LARGE SWATH OF STRONG MID-UPPER LEVEL DRYING EDGING SLOWLY EWD ACROSS THE ERN GOMEX AND TWD WRN FL. A POS TILT TROUGH IS ALSO NOTED UPSTREAM...WITH ITS AXIS EXTENDING FROM LK SUPR SWWD ACROSS THE UPR MS VLY...AND INTO KS/OK/TX/NM. TODAY/TONIGHT...AS THE UPPER TROUGH WELL UPSTREAM DIGS SEWD TWD THE OH/TN AND MID MS VLYS...IT WILL BEGIN TO EJECT THE GOMEX LOW E-ENE WITH IT'S MID-UPPER REFLECTION OPENING UP INTO A TROUGH AS IT MOVES OVER FL THRU TONIGHT. SYNOPTIC SCALE LIFT VIA WIDESPREAD H25 DIVG/INCRSG H50 PVA WILL KEEP CWA SOCKED IN WITH CLOUDS AND ALLOWING FOR REGENERATION OF SHRA/ISOLD TS THROUGHOUT THE DAY. MID-UPPER WINDS SHIFTING TO SW WILL BEGIN TO ADVECT SHARP DRYING (ABOVE H60) INTO THE PENINSULA...RESULTING IN MUCH LOWER PWAT AIR BEGINNING TONIGHT. && .MARINE...MINIMAL CHGS TO THE CWF AS BUOY OBS STILL SUPPORT SCA SEAS EVERYWHERE...WITH MUCH STRONGER WINDS OVER THE 20-60NM LEG (20KT AT 41010...SO 15-20 IS PROBABLY A SAFE BET THERE). MAY BE ABLE TO PARE OUTER LEGS BACK TO JUST AN ADV FOR SEAS TONIGHT. && .AVIATION...ANTICIPATE SCT MVFR SHRA BECMG NMRS WITH ISOLD IFR CIGS/ VSBYS/TS DURING THE AFTN AND EARLY EVENING HRS. && && .MLB WATCHES/WARNINGS/ADVISORIES... ...SMALL CRAFT ADVISORY FOR SEAS COCOA BEACH TO JUPITER INLET 0-20 NM OFFSHORE. ...SMALL CRAFT ADVISORY COCOA BEACH TO JUPITER INLET 20-60 NM OFFSHORE. && $$ SHORT TERM...CRISTALDI LONG TERM....PENDERGRAST fl AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NORTHERN INDIANA 625 PM EST FRI OCT 7 2005 .AVIATION/UPDATE... SATELLITE IMAGERY THIS EVENING DEPICTED AN AREA OF STRATOCUMULUS ACRS SRN MICHIGAN/NRN INDIANA/NW OHIO. CLOUD HEIGHTS WERE GENERALLY AROUND 4500 FEET...WHICH IS CLOSE TO THE 850 MB LVL. 18Z NAM WAS NOT PICKING UP ON THIS MSTR...WHILE THE 18Z GFS AND THE LATEST RUC40 WERE CAPTURING IT MUCH BETTER. BELIEVE STRATOCUMULUS DECK WILL LINGER FOR AWHILE UNTIL A S/WV...CURRENTLY MOVING INTO THE REGION...PASSES BY...AND HOPEFULLY BRINGS SOME SUBSIDENCE TO ERODE THE CLOUD DECK. WITH THAT SAID...WILL KEEP BKN STRATOCUMULUS AT KSBN UNTIL 06Z AND AT KFWA UNTIL 09Z. AFOREMENTIONED S/WV WILL BE EAST OF THE FCST AREA BY 15Z...ALLOWING MID LVL RIDGING TO TAKE PLACE IN ITS WAKE. CUMULUS RULE DOES NOT GENERATE MUCH IN THE WAY OF DIURNAL CUMULUS CLOUDS ON SATURDAY...PROBABLY DUE IN PART THAT 850 MB TEMPS ARE EXPECTED TO MODERATE...EQUATING INTO A LESS STEEP LAPSE RATE (NOT AS UNSTABLE). CLOSER EXAMINATION OF MODEL SOUNDINGS INDICATE THAT MSTR BETWEEN THE 925 MB AND 850 MB LAYER MAY GENERATE SOME DIURNAL CUMULUS CLOUDS BETWEEN 2000 AND 3000 FEET. WILL ADD SCT CUMULUS CLOUDS AT THE TAFS AROUND 14Z...ALONG WITH SLIGHTLY HIGHER SUSTAINED WINDS DUE TO MIXING. WILL NOT GO BKN MVFR ATTM AS CONFIDENCE IS LOW AT THIS POINT ON WHAT THE COVERAGE WILL BE. && .PREVIOUS DISCUSSION... SHORT TERM... TONIGHT AND SATURDAY SURFACE ANALYSIS SHOWING SURFACE FRONT WHICH PUSHED THROUGH THE OHIO VALLEY YESTERDAY NOW WELL EAST ACROSS CENTRAL NY INTO WESTERN PA. ASSOCIATED SLOPING FRONTAL ZONE IS VERY SHALLOW HOWEVER WITH SW FLOW AS LOW AS 800MB CONTINUING OVER THE CWA TODAY. A PACKET OF ENERGY AND MOISTURE FROM THE REMNANTS OF TS TAMMY IS BECOMING CAPTURED BY THE SW FLOW ALOFT AND IS MOVING NORTH UP THE APPALACHIANS. DIFFERENTIAL THERMAL ADVECTION ACROSS THE AFOREMENTIONED SLOPING FRONTAL BOUNDARY HAS PRODUCED WIDESPREAD SHOWERS OVER CENTRAL OHIO TODAY. EXPECT ANY RAIN TO REMAIN EAST OF THE CWA TONIGHT WITH DEEPEST MOISTURE AND LIFT REMAINING FROM CENTRAL OHIO EASTWARD. OTHERWISE MAIN FORECAST CONCERN OVERNIGHT REVOLVES AROUND CLOUD AND TEMPERATURE FORECAST. EXPANSIVE STRATOCUMULUS DECK HAS DEVELOPED OVER MUCH OF CENTRAL AND NORTHERN MICHIGAN TODAY. MEANWHILE OVER MUCH OF INDIANA NOT MUCH AT ALL IN THE WAY OF DIURNAL CU HAVE FORMED TODAY DUE TO A STEEP AND SHALLOW INVERSION. NAM VERY AGGRESSIVE IN ADVECTING THIS LOW LEVEL MOISTURE/CLOUD FIELD SOUTH ACROSS THE CWA TONIGHT UNDERNEATH THE STEEPENING FRONTAL INVERSION. THE TYPICAL BIAS OF THE NAM IS TO BE TOO MOIST IN THE LOW LEVELS. WILL CARRY MORE CLOUD COVER ACROSS THE NORTH TONIGHT BUT WILL LEAN TOWARDS THE LESS MOIST GFS AND GO WITH PARTLY CLOUDY WORDING. THE ONLY EXCEPTION WILL BE OVER NW OHIO CLOSER TO THE THICKER FRONTAL CLOUD SHIELD WHERE MOSTLY CLOUDY WORDING WILL BE USED. DECENT PRESSURE GRADIENT REMAINS TONIGHT WHICH WILL PREVENT THE SURFACE FROM FULLY DECOUPLING. WILL GO WITH LOWS IN THE LOW 40S MOST AREAS WITH A FEW UPPER 30S FROM KGSH TO KBEH. QUIET SENSIBLE WEATHER CONTINUES FOR SATURDAY. AGAIN A DIFFICULT CLOUD FORECAST WITH EXTENT OF CU FORMATION IN QUESTION. WILL GO WITH PARTLY CLOUDY WORDING EVERYWHERE FOR NOW WITH HIGHEST CLOUD PERCENTAGE IN THE EAST CLOSER TO PERSISTENT FRONTAL ZONE OVER OHIO. HIGH TEMPERATURES GENERALLY IN THE UPPER 50S. LONG TERM... SATURDAY NIGHT THROUGH FRIDAY BLOCKY SPLIT FLW ACRS CONUS THIS PD W/DOMINANT SRN STREAM DICTATING SENSIBLE WX PATTN AND GENERAL DETACHMENT FM NRN STREAM ACRS ERN US KEEPING THINGS MILD. OF NOTE CONTS TO BE SFC RIDGING THRU THE GOMEX AND LACK OF RTN FLW DVLPMNT...ESPECIALLY INADV OF STG SW TROF OVER NE PAC WHICH DIGS INLAND INTO FOUR CORNERS EARLY ON AND WHICH THEN EJECTS OUT AND MINORS MID NXT WEEK. LEAD IMPULSE AHD OF THIS FTR LIFTING OUT OF SRN PLAINS MON LOOKS MSTR STARVED TOO W/LTL MORE THEN MID/HIGH CLD INCREASE THEN SO HAVE KEPT THINGS DRY AT THIS POINT. OTHERWISE...SLOW TEMP MODERATION ON TAP W/AOA READINGS XPCD BY TUE. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...SMALL CRAFT ADVISORY UNTIL 5 PM EST SATURDAY FOR LMZ043-LMZ046. && $$ AVIATION/UPDATE...HICKMAN SHORT TERM...HITCHCOCK LONG TERM....HOLSTEN in AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NORTHERN INDIANA 1257 PM EST FRI OCT 7 2005 .AVIATION... LOWER MVFR CIGS FROM EARLIER THIS MORNING HAVE ERODED AWAY TODAY WITH PLENTY OF MID AND UPPER LEVEL CLOUD STREAMING OVER NORTHERN INDIANA AND MICHIGAN IN ADVANCE OF A STRONG MID LEVEL SHORTWAVE. THIS HIGH CLOUD COVER SHOULD PREVENT ANY ROBUST DIURNAL CU DEVELOPMENT THIS AFTERNOON WITH LIMITED SURFACE HEATING. MAIN CONCERN FOR TONIGHT REVOLVES AROUND POTENTIAL FOR STRATUS DECK TO REFORM. NAM IS VERY AGGRESSIVE WITH LOW LEVEL MOISTURE BECOMING TRAPPED BENEATH A STEEPENING SUBSIDENCE INVERSION OVERNIGHT INTO SATURDAY MORNING WHILE GFS IS MUCH LEANER WITH LOW LEVEL MOISTURE FIELDS. NAM TYPICALLY TOO AGGRESSIVE WITH LOW LEVEL MOISTURE ALTHOUGH IT MAY HAVE SOME CREDENCE GIVEN THE EXPANSIVE STRATUS DECK UPSTREAM OVER CENTRAL LOWER MICHIGAN. WILL SCATTER CLOUDS OUT FOR THE OVERNIGHT BUT EVENING SHIFT WILL NEED TO MONITOR PROGRESS OF AFOREMENTIONED UPSTREAM MVFR STRATUS DECK FOR POSSIBLE INCLUSION IN LATER TAF ISSUANCES. && .PREV DISCUSSION... UPDATE... HAVE UPDATED THE FORECAST PACKAGE THIS MORNING TO REMOVE ALL MENTION OF PRECIP. OVER NW OHIO SHIELD OF RAIN DEVELOPING THIS MORNING AS A PIECE OF THE REMNANTS OF TS TAMMY ADVANCES UP THE MID LATITUDE COLD FRONT WHICH CROSSED OUR REGION YESTERDAY. DIFFERENTIAL THERMAL ADVECTION PATTERN OVER OHIO PRODUCING A REGION OF ISENTROPIC UPGLIDE ACROSS THE SLOPING FRONTAL ZONE. THE WESTERN MOST BAND OF PRECIP HAS NOW PUSHED JUST EAST OF THE CWA AND EXPECT ANY SUBSEQUENT SHOWER DEVELOPMENT TO REMAIN JUST EAST OF A KAOH TO KTOL LINE. HAVE ALSO REMOVED MORNING LAKE EFFECT POPS FOR BERRIEN AND LAPORTE COUNTIES. BOUNDARY LAYER FLOW HAS VEERED NE AS EXPECTED WITH WEAK AND DISORGANIZED BAND OF RAIN SHOWERS REMAINING OFFSHORE. AN INTERESTING NON-EVENT LAKE EFFECT WISE LATE LAST NIGHT. LAKE INDUCED CAPE AROUND 500J/KG AND LAKE INDUCED EQUILIBRIUM LEVELS AROUND 6K FEET. NOT REAL IMPRESSIVE BUT WOULD STILL NORMALLY EXPECT MORE ACTIVITY THAN WAS OBSERVED GIVEN WELL ALIGNED FLOW AND AMPLE MOISTURE BENEATH THE INVERSION. THINK THE MAIN LIMITING FACTOR WAS THE LACK OF FAVORABLE COLD CLOUD MICROPHYSICS WITHIN THE LAKE EFFECT CLOUD PLUME. COLDEST TEMPERATURES WITHIN THE CLOUD LAYER ONLY 0C TO -2C...NOT NEARLY COLD ENOUGH FOR THE BERGERON-FINDEISEN PROCESS WHEREBY SUPERCOOLED WATER DROPLETS DEPOSIT ON ICE CRYSTALS. THE MOST FAVORABLE CLOUD TEMPERATURE RANGE FOR THIS TO OCCUR IS -12C TO -18C. THE RELATIVELY SHALLOW LAKE EFFECT CLOUD LAYER IS TOO SHALLOW FOR EFFICIENT WARM RAIN CLOUD PROCESSES. INTERESTING TO NOTE THAT THE 20KM FSL DEVELOPMENT RUC...NORMALLY RELIABLE IN LAKE EFFECT PRECIPITATION...PERFORMED VERY POORLY AS THE RUNS YESTERDAY DEVELOPED A RATHER POTENT LAKE EFFECT RAIN BAND. AN INTERESTING EVENT...OR NON-EVENT. SHORT TERM... SURFACE HIGH PRESSURE WILL BE OVER THE AREA TODAY AND TONIGHT WHILE AN UPPER LEVEL TROUGH MOVES EASTWARD THROUGH. JUST THE SLIGHTEST OF CHANCES FOR A LITTLE BIT OF LAKE EFFECT RAIN IN THE FAR NORTHWESTERN PART OF OUR CWA THIS MORNING AND ALSO LEFT THE SMALL RAIN CHANCE IN FOR THE FAR SOUTHEASTERN PART OF OUR CWA AS RADARS TO OUR EAST ARE SHOWING RAIN JUST TO OUR EAST MOVING NORTHEASTWARD...ALSO THERE IS AN INVERTED SURFACE TROUGH OVER THE EASTERN UNITED STATES AND MODELS SHOW QPF MOVING NORTHWARD UP THIS AND THE FAR SOUTHEASTERN PART OF OUR CWA IS JUST ON THE EDGE OF THE PRECIP CHANCES. HAVING A SMALL CHANCE FOR RAIN IN THE FAR SOUTHEASTERN PART OF OUR CWA ALSO COLLABORATES WELL WITH NEIGHBORING OFFICES. NUMERICAL GUIDANCE ALSO HAS A SMALL POP FOR THERE. THEN THE SKY COVER SHOULD DECREASE TONIGHT AS THE HIGH PRESSURE WORKS ITS WAY MORE INTO THE AREA AND THE MOISTURE FIELD TO OUR EAST GETS PUSHED FURTHER EASTWARD. WITH NORTHERLY WINDS TODAY AND TONIGHT...TEMPERATURES WILL REMAIN ON THE COOL SIDE. LONG TERM... SATURDAY THROUGH THURSDAY... COUPLE OF SYSTEMS OF CONCERN THAT MAY EVENTUALLY ALTER AN OTHERWISE DRY FORECAST. FIRST WILL BE REMNANTS OF TAMMY MOVING UP ALONG APPLACIANS. AS IT DOES..HIGH PRESSURE BUILDING IN OVER SOUTHEASTERN CANADA THAT WILL COMBINE TO GENERATE STRONG EASTERLY FLOW THAT WILL SPREAD MOISTURE WESTWARD TOWARD OUR OHIO COUNTIES. HOWEVER...BEST MOISTURE AND LIFT WILL RIDE UP ALONG THE APPLACIANS KEEPING THE BETTER CHANCES FOR PRECIP TO OUR EAST INITIALLY THROUGH THE WEEKEND. UPPER TROUGH THEN KICKS OUT OF SOUTHERN PLAINS AND TAKES ON NEGATIVE TILT AS IT MOVES UP INTO THE OHIO VALLEY...SUSTAINING CLOUD COVER OVER THE AREA BEGINNING OF NEXT WEEK. CLOSED LOW THEN PROGGED TO MOVE OUT OF FOUR CORNERS REGION AND INTO THE CENTRAL PLAINS. ONLY SFC REFLECTION FROM GFS ATTM IS INVERTED TROUGH. UPPER LOW OPENS UP AND SHEARS OUT AS IT TRIES TO CONTINUE EASTWARD PROVIDING ENOUGH UNCERTAINTY TO AGAIN STAY WITH DRY FORECAST. TEMPERATURES THROUGHOUT THE EXTENDED PERIOD EXPECTED TO REMAIN CLOSE TO NORMAL FOR THIS TIME OF YEAR. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...SMALL CRAFT ADVISORY UNTIL 5 PM EST SATURDAY FOR LMZ043-LMZ046. && $$ AVIATION/UPDATE...HITCHCOCK SHORT TERM...BML LONG TERM....JAL in AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NORTHERN INDIANA 1016 AM EST FRI OCT 7 2005 .UPDATE... HAVE UPDATED THE FORECAST PACKAGE THIS MORNING TO REMOVE ALL MENTION OF PRECIP. OVER NW OHIO SHIELD OF RAIN DEVELOPING THIS MORNING AS A PIECE OF THE REMNANTS OF TS TAMMY ADVANCES UP THE MID LATITUDE COLD FRONT WHICH CROSSED OUR REGION YESTERDAY. DIFFERENTIAL THERMAL ADVECTION PATTERN OVER OHIO PRODUCING A REGION OF ISENTROPIC UPGLIDE ACROSS THE SLOPING FRONTAL ZONE. THE WESTERN MOST BAND OF PRECIP HAS NOW PUSHED JUST EAST OF THE CWA AND EXPECT ANY SUBSEQUENT SHOWER DEVELOPMENT TO REMAIN JUST EAST OF A KAOH TO KTOL LINE. HAVE ALSO REMOVED MORNING LAKE EFFECT POPS FOR BERRIEN AND LAPORTE COUNTIES. BOUNDARY LAYER FLOW HAS VEERED NE AS EXPECTED WITH WEAK AND DISORGANIZED BAND OF RAIN SHOWERS REMAINING OFFSHORE. AN INTERESTING NON-EVENT LAKE EFFECT WISE LATE LAST NIGHT. LAKE INDUCED CAPE AROUND 500J/KG AND LAKE INDUCED EQUILIBRIUM LEVELS AROUND 6K FEET. NOT REAL IMPRESSIVE BUT WOULD STILL NORMALLY EXPECT MORE ACTIVITY THAN WAS OBSERVED GIVEN WELL ALIGNED FLOW AND AMPLE MOISTURE BENEATH THE INVERSION. THINK THE MAIN LIMITING FACTOR WAS THE LACK OF FAVORABLE COLD CLOUD MICROPHYSICS WITHIN THE LAKE EFFECT CLOUD PLUME. COLDEST TEMPERATURES WITHIN THE CLOUD LAYER ONLY 0C TO -2C...NOT NEARLY COLD ENOUGH FOR THE BERGERON-FINDEISEN PROCESS WHEREBY SUPERCOOLED WATER DROPLETS DEPOSIT ON ICE CRYSTALS. THE MOST FAVORABLE CLOUD TEMPERATURE RANGE FOR THIS TO OCCUR IS -12C TO -18C. THE RELATIVELY SHALLOW LAKE EFFECT CLOUD LAYER IS TOO SHALLOW FOR EFFICIENT WARM RAIN CLOUD PROCESSES. INTERESTING TO NOTE THAT THE 20KM FSL DEVELOPMENT RUC...NORMALLY RELIABLE IN LAKE EFFECT PRECIPITATION...PERFORMED VERY POORLY AS THE RUNS YESTERDAY DEVELOPED A RATHER POTENT LAKE EFFECT RAIN BAND. AN INTERESTING EVENT...OR NON-EVENT. && .PREV DISCUSSION... AVIATION... THE NARROW BAND OF CLOUDS OVER SBN AND TO THE WEST OF SBN WILL CONTINUE THERE TODAY UNTIL THE HIGH WORKS ITS WAY MORE INTO THE REGION THIS EVENING, PUSHING THEM EASTWARD. FWA SHOULD REMAIN ON THE PERIPHERY OF ANY CLOUD SHIELDS TODAY MAINTAINING MID AND HIGH LEVEL VFR CLOUDS AT FWA. THE POSITION OF THE HIGH TODAY AND TONIGHT WILL KEEP THE WIND BLOWING OUT OF THE NORTHEAST. THE PRESSURE GRADIENT ALONG WITH THE SUN'S ENERGY TODAY WILL INCREASE THE WIND SPEEDS SOME DURING THE DAYTIME HOURS. .SHORT TERM... SURFACE HIGH PRESSURE WILL BE OVER THE AREA TODAY AND TONIGHT WHILE AN UPPER LEVEL TROUGH MOVES EASTWARD THROUGH. JUST THE SLIGHTEST OF CHANCES FOR A LITTLE BIT OF LAKE EFFECT RAIN IN THE FAR NORTHWESTERN PART OF OUR CWA THIS MORNING AND ALSO LEFT THE SMALL RAIN CHANCE IN FOR THE FAR SOUTHEASTERN PART OF OUR CWA AS RADARS TO OUR EAST ARE SHOWING RAIN JUST TO OUR EAST MOVING NORTHEASTWARD...ALSO THERE IS AN INVERTED SURFACE TROUGH OVER THE EASTERN UNITED STATES AND MODELS SHOW QPF MOVING NORTHWARD UP THIS AND THE FAR SOUTHEASTERN PART OF OUR CWA IS JUST ON THE EDGE OF THE PRECIP CHANCES. HAVING A SMALL CHANCE FOR RAIN IN THE FAR SOUTHEASTERN PART OF OUR CWA ALSO COLLABORATES WELL WITH NEIGHBORING OFFICES. NUMERICAL GUIDANCE ALSO HAS A SMALL POP FOR THERE. THEN THE SKY COVER SHOULD DECREASE TONIGHT AS THE HIGH PRESSURE WORKS ITS WAY MORE INTO THE AREA AND THE MOISTURE FIELD TO OUR EAST GETS PUSHED FURTHER EASTWARD. WITH NORTHERLY WINDS TODAY AND TONIGHT...TEMPERATURES WILL REMAIN ON THE COOL SIDE. LONG TERM... SATURDAY THROUGH THURSDAY... COUPLE OF SYSTEMS OF CONCERN THAT MAY EVENTUALLY ALTER AN OTHERWISE DRY FORECAST. FIRST WILL BE REMNANTS OF TAMMY MOVING UP ALONG APPLACIANS. AS IT DOES..HIGH PRESSURE BUILDING IN OVER SOUTHEASTERN CANADA THAT WILL COMBINE TO GENERATE STRONG EASTERLY FLOW THAT WILL SPREAD MOISTURE WESTWARD TOWARD OUR OHIO COUNTIES. HOWEVER...BEST MOISTURE AND LIFT WILL RIDE UP ALONG THE APPLACIANS KEEPING THE BETTER CHANCES FOR PRECIP TO OUR EAST INITIALLY THROUGH THE WEEKEND. UPPER TROUGH THEN KICKS OUT OF SOUTHERN PLAINS AND TAKES ON NEGATIVE TILT AS IT MOVES UP INTO THE OHIO VALLEY...SUSTAINING CLOUD COVER OVER THE AREA BEGINNING OF NEXT WEEK. CLOSED LOW THEN PROGGED TO MOVE OUT OF FOUR CORNERS REGION AND INTO THE CENTRAL PLAINS. ONLY SFC REFLECTION FROM GFS ATTM IS INVERTED TROUGH. UPPER LOW OPENS UP AND SHEARS OUT AS IT TRIES TO CONTINUE EASTWARD PROVIDING ENOUGH UNCERTAINTY TO AGAIN STAY WITH DRY FORECAST. TEMPERATURES THROUGHOUT THE EXTENDED PERIOD EXPECTED TO REMAIN CLOSE TO NORMAL FOR THIS TIME OF YEAR. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...SMALL CRAFT ADVISORY UNTIL 5 PM EST SATURDAY FOR LMZ043-LMZ046. && $$ UPDATE...HITCHCOCK SHORT TERM/AVIATION...BML LONG TERM....JAL in AREA FORECAST DISCUSSION...UPDATE NATIONAL WEATHER SERVICE LOUISVILLE KY 1015 PM EDT FRI OCT 7 2005 .EVENING UPDATE... UPDATED FORECAST TO TAKE OUT THE EVENING WORDING AND MAKE A FEW MINOR CHANGES TO THE GRIDS. LOW CLOUDS ARE HOLDING OVER THE FA WITH SOME REDEVELOPMENT OF CLOUDS ALONG THE WESTERN EDGE OF THE CLOUDS. CLOUD BASES REMAIN HIGHER ALONG THE WESTERN SECTIONS...3-5 THSD FT...WHILE LOWER CEILINGS...BELOW 1 THSD FT...AND DRIZZLE CONTINUE ACROSS THE EASTERN PARTS OF THE FA. WILL CONTINUE TREND OF GRADUALLY SPREADING THE CLOUD COVER TO THE WEST AS THE NIGHT PROGRESSES. CLOUDS WILL BE SLOW TO CLEAR IN THE MORNING WITH SOME BREAKS DEVELOPING DURING THE DAY. NO OTHER SIGNIFICANT CHANGES MADE TO PREVIOUS FORECAST. - SCHOLZ .SHORT TERM (TONIGHT AND SATURDAY)... SHORT TERM FCST STILL CENTERS ON CLOUD-CLEAR LINE AND RESULTANT TEMPS FOR TNGT AND SATURDAY. LATEST VIS IMAGERY AT 1830 UTC SHOW SHARP CLOUD GRADIENT FROM S-CNTRL IN TO BARELY W OF SDF TO ABOUT MIDWAY BTWN HOP AND BWG (OR APPROACHING RUSSELLVILLE). TRENDS IN OBS DATA AND LATEST RUC AND NAM MODEL DATA SUGGEST CLEARING LINE SHOULD MAKE IT TO OR JUST PAST SDF AND BWG LATE THIS AFTN CONTINUING INTO EARLY EVNG. THIS SHOULD ALLOW TEMPS TO RISE A FEW DEGREES LATE THIS AFTN ALONG AND W OF THIS LINE. FARTHER E...CLOUDS WILL REMAIN SOCKED IN ALONG WITH PATCHY LGT RAIN LATE THIS AFTN AND EVNG ASSOCD WITH UPR DEFORMATION ZONE...SO WILL CONT WITH MENTION OF SCT SHOWERS THERE. ALSO...BNA DOPPLER RADAR SHOWING SEPARATE AREA OF SHOWERS OVER ERN TN MOVING NEWD AT THIS TIME. LOOKS LIKE THIS WILL MOSTLY REMAIN E OF FCST AREA. AS FOR LATER TNGT...ALL SHORT TERM MODELS INDICATE THAT CLEARING LINE WILL STOP ITS EWD PROGRESS AND LIKELY DRIFT WESTWARD AGAIN AS BNDRY-LAYER (E.G. 925 MB) WINDS BECOME MORE NELY. TIME-HT CROSS SECTIONS AND MODEL SOUNDINGS CONT TO SHOW SATURATED BNDRY LAYER BENEATH INVERSION AND DRIER AIR ALOFT. AS A RESULT...SKY WILL REMAIN CLOUDY EASTERN AREAS AND SHOULD BECOME MSTLY CLOUDY OR CLOUDY WESTERN AREAS ALONG WITH PATCHY DRZL OVERNGT. TEMPS TNGT SHOULD NOT FALL TOO MUCH UNDER THE CLOUD COVER. LOWEST TEMPS SHOULD BE IN WRN PART OF S-CNTRL IN WHERE CLOUDS WILL NOT COME BACK UNTIL LATER TNGT. ON SATURDAY...MODEL SOUNDINGS AND COOL NLY/NELY BNDRY LYR FLOW SUGGEST LOW CLOUDS WILL AGAIN REMAIN PERSISTENT OVER MOST OF FCST AREA. THIS ALSO WILL HAVE A BIG IMPACT ON TEMPS...WHICH SHOULD KEEP DIURNAL RISE LIMITED. THUS...FAVOR THE OVERALL LOWER MET GUIDANCE MAX TEMPS FOR SATURDAY VS. THE HIGHER NGM AND GFS BASED MOS. -TWF .LONG TERM (SATURDAY NIGHT THROUGH FRIDAY)... THE FIRST MAJOR PROBLEM IS DEALING WITH THE MIX OF CLOUDS AND POSSIBLE R-/L- DURING THE SATURDAY NIGHT INTO MONDAY TIME FRAME. LATEST GFS AND NAM MODEL SOUNDINGS AND TIME-HT CROSS SECTIONS INDICATE CONSIDERABLE LOW LEVEL RH LINGERING ACROSS MOST IF NOT ALL OF FCST AREA DURING THE ABOVE MENTIONED TIME PERIOD. SO MOSTLY CLOUDY SKIES THROUGH THIS PERIOD LOOKS GOOD BUT WITH A TIGHT CLEAR TO CLOUD GRADIENT JUST TO THE WEST OF FCST AREA...MUCH LIKE TODAY. USING THE NAM AS MODEL OF CHOICE TODAY...IT FORECASTS A SHORT WAVE TO MOVE ACROSS THE FCST AREA ON SUNDAY NIGHT INTO MONDAY...WITH THE DEEPEST RH AND MOST LIFT TO THE EAST...WE WILL INTRODUCE A CHANCE OF R- AND L- DURING SUNDAY NIGHT INTO MONDAY MORNING OVER THE EASTERN THIRD OF THE FCST AREA. LOWERED MAXS AND RAISED MINS A FEW DEGS DURING THIS TIME FRAME BECAUSE OF THE INCREASED CLOUD COVER. DRY AND COOL HIGH PRESSURE WILL BE THE RULE ON MONDAY NIGHT INTO WEDNESDAY TIME PERIOD. THE FINAL MAJOR FORECAST PROBLEM IS POSSIBLE SHOWERS LATE IN THE NEXT WORK WEEK. WITH THE LATEST MODEL DATA GUIDANCE CONTINUING TO INDICATE A CLOSED 500 MB LOW MOVING INTO THE CENTRAL U.S. DURING THE MID AND LATE TIME PERIOD NEXT WEEK...AND HPC GUIDANCE INDICATING SAME...WE DECIDED ON INTRODUCING A SMALL CHANCE OF SHOWERS DURING THE WEDNESDAY NIGHT THROUGH THURSDAY NIGHT PERIOD. BUT...THE BASIC TEMP TRENDS CONTINUE TO BE MORE OR LESS IN LINE WITH THE CURRENT FCST PROJECTIONS SO NOT MUCH CHANGES MADE THERE. --21 && .LMK WATCHES/WARNINGS/ADVISORIES... KY...NONE. IN...NONE. && $$ ky AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE PADUCAH KY 327 PM CDT FRI OCT 7 2005 .DISCUSSION... .SHORT TERM/TONIGHT THROUGH SUNDAY/... COLD AIR STRATOCUMULUS SLOWLY ROTATING SOUTHEASTWARD THROUGH NRN 1/2 OF ILLINOIS THIS AFTERNOON ASSOCIATED WITH SMALL SCALE...SHORTWAVE UPPER LOW. THE 12KM NAM AND 40KM RUC ARE SLOWER WITH THE E-SEWD TRANSLATION OF THIS FEATURE TOWARD THE PAH FORECAST AREA AND IS PREFERRED FOR CLOUD COVER FORECAST THIS EVENING AND OVERNIGHT. GIVEN THE PASSAGE OF THIS SHORTWAVE/LOW...AGEOSTROPHIC WIND RESPONSE AND LOWERED MIXING RATIOS IN THE LOWER ATMOSPHERE SHOULD INHIBIT THE PRODUCTION OF ANY WIDESPREAD FROST IN THE PAH FORECAST AREA...AS WELL AS ANY DRIZZLE ON THE EASTERN END OF THE FORECAST AREA. ABOUT THE ONLY ARE WHERE FROST MAY OCCUR WILL BE IN THE PROTECTED AREAS OF THE SOUTHEAST MISSOURI FOOTHILLS...MAINLY IN CARTER/WAYNE COUNTIES IN MISSOURI. ALTHOUGH A MARKED DROP OF 4 DEGREES FAHRENHEIT AT WFO PAH...SOIL TEMPERATURES WERE STILL RANGING BETWEEN 68-76 DEGREES TODAY...DEPENDING ON THE GROUND COVER. THE FLUX OF TERRESTRIAL RADIATION SHOULD INHIBIT TOO MUCH COOLING OF GROUND SURFACE OVERNIGHT. HIGH PRESSURE AND CONTINUED COLD AIR ADVECTION PERSISTS THROUGH SATURDAY...WITH A STRONG DRY AIR INTRUSION THROUGH THE REGION. THE CLOUD COVER FORECAST MAY BE TOO PESSIMISTIC...SO LATER SHIFTS MAY NEED TO REDUCE CLOUD COVER TO MOSTLY CLEAR/SUNNY CATEGORY. NAM/GFS GENERATE A CLOSED LOW OVER OK/ERN TX ON SUNDAY...BUT GIVEN THE LACK OF SIGNIFICANT MOISTURE...THIS FEATURE WILL DO LITTLE EXCEPT TO ADD A FEW CLOUDS AND SLIGHTLY RETARD THE DIURNAL INCREASE IN TEMPERATURES. .LONG TERM/MONDAY THROUGH FRIDAY/... MEDIUM RANGE MODELS DEVELOP A CLOSED LOW ACROSS THE WESTERN U.S...AND SLOWLY BUILD A SHORT WAVE RIDGE ACROSS THE PAH FORECAST AREA MONDAY THROUGH WEDNESDAY. THIS CLOSED LOW EVENTUALLY IS PROGGED BY THE NAM/GFS NUMERICAL MODELS TO TRANSLATE INTO THE NORTHERN AND CENTRAL PLAINS...WORKING TOWARD THE MID MISSISSIPPI VALLEY. GIVEN THE LACK OF DEEP MOISTURE FROM THE GULF OF MEXICO...THE ONLY MOISTURE AVAILABLE WILL BE THAT PULLED WITH THE SYSTEM ITSELF. INTRODUCED A SMALL CHANCE OF LIGHT RAINSHOWERS INTO PART OF SOUTHWEST IL WEDNESDAY NIGHTA AS ANOTHER SHORTWAVE ROTATES SEWD (NW FLOW) AROUND THE BASE OF THE UPPER TROUGH/LOW (WHICH MOVES INTO THE NORTHERN GREAT LAKES)...BUT VERY RELUCTANTLY. SUSPECT THAT DRY CONDITIONS WILL STILL PREVAIL AT THIS TIME. OTHERWISE...DRY AND SEASONABLE CONDITIONS WILL PREVAIL THROUGH NEXT WEEKEND...AS COOLER AIR IS REINFORCED OVER THE CONTINENTAL U.S. EAST OF THE EASTERN PACIFIC RIDGE. && .PAH WATCHES/WARNINGS/ADVISORIES... KY...NONE. MO...NONE. IL...NONE. IN...NONE. && $$ SMITH ky AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LOUISVILLE KY 245 PM EDT FRI OCT 7 2005 .SHORT TERM (TONIGHT AND SATURDAY)... SHORT TERM FCST STILL CENTERS ON CLOUD-CLEAR LINE AND RESULTANT TEMPS FOR TNGT AND SATURDAY. LATEST VIS IMAGERY AT 1830 UTC SHOW SHARP CLOUD GRADIENT FROM S-CNTRL IN TO BARELY W OF SDF TO ABOUT MIDWAY BTWN HOP AND BWG (OR APPROACHING RUSSELLVILLE). TRENDS IN OBS DATA AND LATEST RUC AND NAM MODEL DATA SUGGEST CLEARING LINE SHOULD MAKE IT TO OR JUST PAST SDF AND BWG LATE THIS AFTN CONTINUING INTO EARLY EVNG. THIS SHOULD ALLOW TEMPS TO RISE A FEW DEGREES LATE THIS AFTN ALONG AND W OF THIS LINE. FARTHER E...CLOUDS WILL REMAIN SOCKED IN ALONG WITH PATCHY LGT RAIN LATE THIS AFTN AND EVNG ASSOCD WITH UPR DEFORMATION ZONE...SO WILL CONT WITH MENTION OF SCT SHOWERS THERE. ALSO...BNA DOPPLER RADAR SHOWING SEPARATE AREA OF SHOWERS OVER ERN TN MOVING NEWD AT THIS TIME. LOOKS LIKE THIS WILL MOSTLY REMAIN E OF FCST AREA. AS FOR LATER TNGT...ALL SHORT TERM MODELS INDICATE THAT CLEARING LINE WILL STOP ITS EWD PROGRESS AND LIKELY DRIFT WESTWARD AGAIN AS BNDRY-LAYER (E.G. 925 MB) WINDS BECOME MORE NELY. TIME-HT CROSS SECTIONS AND MODEL SOUNDINGS CONT TO SHOW SATURATED BNDRY LAYER BENEATH INVERSION AND DRIER AIR ALOFT. AS A RESULT...SKY WILL REMAIN CLOUDY EASTERN AREAS AND SHOULD BECOME MSTLY CLOUDY OR CLOUDY WESTERN AREAS ALONG WITH PATCHY DRZL OVERNGT. TEMPS TNGT SHOULD NOT FALL TOO MUCH UNDER THE CLOUD COVER. LOWEST TEMPS SHOULD BE IN WRN PART OF S-CNTRL IN WHERE CLOUDS WILL NOT COME BACK UNTIL LATER TNGT. ON SATURDAY...MODEL SOUNDINGS AND COOL NLY/NELY BNDRY LYR FLOW SUGGEST LOW CLOUDS WILL AGAIN REMAIN PERSISTENT OVER MOST OF FCST AREA. THIS ALSO WILL HAVE A BIG IMPACT ON TEMPS...WHICH SHOULD KEEP DIURNAL RISE LIMITED. THUS...FAVOR THE OVERALL LOWER MET GUIDANCE MAX TEMPS FOR SATURDAY VS. THE HIGHER NGM AND GFS BASED MOS. -TWF .LONG TERM (SATURDAY NIGHT THROUGH FRIDAY)... THE FIRST MAJOR PROBLEM IS DEALING WITH THE MIX OF CLOUDS AND POSSIBLE R-/L- DURING THE SATURDAY NIGHT INTO MONDAY TIME FRAME. LATEST GFS AND NAM MODEL SOUNDINGS AND TIME-HT CROSS SECTIONS INDICATE CONSIDERABLE LOW LEVEL RH LINGERING ACROSS MOST IF NOT ALL OF FCST AREA DURING THE ABOVE MENTIONED TIME PERIOD. SO MOSTLY CLOUDY SKIES THROUGH THIS PERIOD LOOKS GOOD BUT WITH A TIGHT CLEAR TO CLOUD GRADIENT JUST TO THE WEST OF FCST AREA...MUCH LIKE TODAY. USING THE NAM AS MODEL OF CHOICE TODAY...IT FORECASTS A SHORT WAVE TO MOVE ACROSS THE FCST AREA ON SUNDAY NIGHT INTO MONDAY...WITH THE DEEPEST RH AND MOST LIFT TO THE EAST...WE WILL INTRODUCE A CHANCE OF R- AND L- DURING SUNDAY NIGHT INTO MONDAY MORNING OVER THE EASTERN THIRD OF THE FCST AREA. LOWERED MAXS AND RAISED MINS A FEW DEGS DURING THIS TIME FRAME BECAUSE OF THE INCREASED CLOUD COVER. DRY AND COOL HIGH PRESSURE WILL BE THE RULE ON MONDAY NIGHT INTO WEDNESDAY TIME PERIOD. THE FINAL MAJOR FORECAST PROBLEM IS POSSIBLE SHOWERS LATE IN THE NEXT WORK WEEK. WITH THE LATEST MODEL DATA GUIDANCE CONTINUING TO INDICATE A CLOSED 500 MB LOW MOVING INTO THE CENTRAL U.S. DURING THE MID AND LATE TIME PERIOD NEXT WEEK...AND HPC GUIDANCE INDICATING SAME...WE DECIDED ON INTRODUCING A SMALL CHANCE OF SHOWERS DURING THE WEDNESDAY NIGHT THROUGH THURSDAY NIGHT PERIOD. BUT...THE BASIC TEMP TRENDS CONTINUE TO BE MORE OR LESS IN LINE WITH THE CURRENT FCST PROJECTIONS SO NOT MUCH CHANGES MADE THERE. --21 && .LMK WATCHES/WARNINGS/ADVISORIES... KY...NONE. IN...NONE. && $$ ky AREA FORECAST DISCUSSION...CORRECTED NATIONAL WEATHER SERVICE SHREVEPORT LA 956 PM CDT FRI OCT 7 2005 .DISCUSSION... COLD FRONT HAS PUSHED WELL OFFSHORE THE COAST THIS EVENING...AND PRESSURE GRADIENT HAS RELAXED A BIT SINCE SUNSET. WELL DEFINED SHORTWAVE TROUGH NOW PIVOTING SLOWLY SE INTO NW TX WILL MAKE VERY SLOW PROGRESS EASTWARD ACROSS N TX THROUGH THE NEXT 24 HRS...RESULTING IN A CONTINUED INFLUX OF SUBTROPICAL MOISTURE ALOFT FROM THE E PACIFIC. OF MAIN CONCERN IS THE LOW AC DECK HANGING TOUGH ACROSS NE TX/EXTREME SW AR...WHICH APPEARS THE BE ALONG A WEAK 750-700MB TROUGH AXIS EXTENDING FROM THE RED RIVER VALLEY INTO W LA. 3 KM WINDS FROM DEQ PROFILER REMAIN VERY WEAK FROM THE N...WHICH HOLDS TRUE AS THE N EDGE OF THIS CLOUD BANK IS DRIFTING EVER SO SLOWLY S. PSN WIND PROFILER INDICATING A SLIGHTLY MORE PROGRESSIVE W WIND ALONG THE BASE OF THE TROUGH...WITH AC DECK ABOUT TO MOVE INTO LFK. RUC/00Z NAM INDICATING CLOUD DECK MOVING VERY LITTLE OVERNIGHT...PERHAPS ENCOMPASSING REMAINDER OF DEEP E TX/EXTREME NW LA OVERNIGHT...THUS HAVE UPDATED THE ZONES TO WORD SKY CONDITIONS AS MOSTLY CLOUDY. WHILE WINDS WILL REMAIN WEAK...THERE SHOULD BE ENOUGH MIXING UNDERNEATH CLOUD BLANKET TO KEEP TEMPS FROM BOTTOMING OUT...CURRENT FORECASTS APPEARED JUST A TAD TOO COOL...SO HAVE RAISED MINS A TAD IN LOCATIONS UNDERNEATH CLOUD COVER. NEW NAM ALSO INDICATING CLOUDS HANGING ON OVER E TX AGAIN TOMORROW...WHICH COULD ALSO HOLD DOWN TEMPS ONCE AGAIN. HAVE MADE APPROPRIATE CHANGES TO SKY CONDITIONS...BUT WILL LEAVE ANY TEMP ADJUSTMENTS FOR SATURDAY TO THE MID SHIFT PENDING ADDITIONAL MODEL INFO/GUIDANCE. UPDATE ALREADY OUT. && .PRELIMINARY POINT TEMPS/POPS... SHV 54 70 53 74 / 0 0 0 0 MLU 53 69 55 71 / 0 0 0 0 DEQ 45 72 44 71 / 0 0 0 0 TXK 50 72 50 71 / 0 0 0 0 ELD 48 70 50 71 / 0 0 0 0 TYR 54 68 52 76 / 0 0 0 0 GGG 54 71 52 76 / 0 0 0 0 LFK 54 71 51 75 / 0 0 0 0 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...NONE. LA...NONE. OK...NONE. TX...NONE. && $$ 15 la AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 710 PM EDT FRI OCT 7 2005 .AVIATION... STRATUS FROM COLD NORTHEAST FLOW AND LAKE INFLUENCE WILL HAVE A TOUGH TIME BREAKING OVERNIGHT AS LOW LEVEL INVERSION STRENGTHENS. WILL HAVE TO MAINTAIN THE MVFR CONDITIONS OVERNIGHT AND SCATTERED CLOUDS OUT AFTER DAYBREAK AS LOWER ATMOSPHERE MIXES AND DRIER AIR WORKS INTO THE AREA. && .SHORT TERM...TONIGHT AND SATURDAY...ISSUED AT 335 PM EDT A BLOCKY AND MESSY UPPER PATTERN ACROSS NOAM WITH TROPICAL REMNANTS PLAGUING THE EASTERN SEABOARD AND PACIFIC JET INFLUX ENTERING THE PACIFIC NORTHWEST. A NOTABLE SHORT WAVE, WITH NOT MUCH MOISTURE AND NO RADAR RETURNS, WAS SLOWLY PROGRESSING ACROSS ILLINOIS AND WITH THE ASSISTANCE OF 100+ 300MB JET ENTRANCE REGION OVERHEAD PROVIDING ENOUGH LIFT FOR CLOUD DEVELOPMENT. ON THE MESOSCALE...BANDS OF STRATUS UNDER THE AC/CS CONTINUE TO COME IN OFF OF LAKE HURON YET NO REPORTS OF PRECIP FROM SURROUNDING RADAR SITES AND OBSERVATIONS. COOL NORTHEAST GRADIENT FLOW WILL DOMINATE THROUGH THE SHORT TERM PERIOD. FOR TONIGHT...BOTH THE NAM AND GFS AGREE WITH SYNOPTIC SCALE SETTING UP OVERNIGHT AS SURFACE HIGH SLIDES ACROSS THE NORTHERN LAKES AND WAVES OF LOW PRESSURE TRACK UP THE EASTERN STATE. THIS WILL PROLONG THE EASTERLY FETCH OFF THE WARM WATERS OF LAKE HURON WITH INVERSION HEIGHTS SLOWLY FALLING THRU THE NIGHT. YET MODELS TEND TO CRASH THESE HEIGHTS TOO SOON AND LOOKING CLOSER AT THE RUC13 AND OTHER EXPERIMENTAL RUNS OF THE RUC/WRF...CONVERGENCE INCREASES OVERNIGHT OVER LAKE HURON INTO SAGINAW BAY WITH EVEN SOME HINT OF LIGHT QPF DEVELOPING INTO THE TRI CITIES REGION AND PORTIONS OF THE THUMB. THIS MIGHT BE THE RESULT OF A MORE CLEARING TREND UPSTREAM AND LAND BREEZE DEVELOPMENT TO ENHANCE CONVERGENCE FIELDS SOMEWHAT. THEREFORE, WE WILL INTRODUCE A CHANCE FOR SOME SPRINKLES FOR THOSE COUNTIES NORTH OF I69 AND EAST OF I75. OTHERWISE, WITH IMPRESSIVE INVERSION SETTING UP OVERNIGHT, LAKE STRATUS WILL LIKELY HOLD ON THROUGH MOST OF THE NIGHT. WITH AFOREMENTIONED SHORT WAVE APPROACHING...MODELS ARE CONSISTENT WITH Q-VECTOR CONVERGENCE THIS EVENING BUT LIMITED MOISTURE ALOFT SHOULD PROHIBIT ANY MENTION OF PRECIP. HEADING INTO SATURDAY ALL AVAILABLE GUIDANCE SUGGESTS THIS SHORT WAVE BECOMES STRUNG OUT AND WEAKENS EITHER OVER OR JUST SOUTHEAST OF THE STATE. EITHER WAY, THIS SHOULD INCREASE SUBSIDENCE FURTHER AND DRIER AIR UPSTREAM WILL BEGIN TO INFILTRATE NORTHERN LAKE HURON AND ASSIST WITH THE BREAK UP OF LAKE STRATUS CLOUDS. SO WE MIGHT START OFF WITH MORE CLOUDS BUT TRANSITION TOWARD MORE SUNSHINE THROUGH THE DAY...PTSUNNY FORECAST! MET NUMBERS LOOK TOO LOW AND LIKELY DUE TO MODELS' HIGH LOW LEVEL MOISTURE CONTENT AND CLOUD COVER. WE WILL SHADE CLOSER TO THE MAV/FWC NUMBERS. && .LONG TERM...SATURDAY NIGHT THROUGH FRIDAY...ISSUED AT 335 PM EDT SATURDAY NIGHT THROUGH SUNDAY NIGHT... SURFACE RIDGE OVER WESTERN GREAT LAKES REGION PRETTY MUCH HELD AT BAY THROUGH THE WEEKEND AS TROUGHING KEEPS REAFFIRMING ITSELF IN THE EAST. AT 500 MB...EARLIER WEAKENED SHORTWAVE TROUGH STILL WOBBLING AROUND VICINITY OF SOUTHEAST MI SATURDAY NIGHT AND SUNDAY. STILL CALLING FOR A RATHER TRANQUIL FORECAST FOR THIS TIME FRAME...WITH LITTLE OR NO SYNOPTIC SCALE LIFT. 850 TO 500 MB RELATIVE HUMIDITY RATHER DRY THROUGH SUNDAY...THEN INCREASING MOISTURE WORKING BACK IN SUNDAY NIGHT. 925 MB MOISTURE...IN MOIST NORTHEAST FLOW...A LITTLE BETTER...THOUGH EVEN THIS INCREASES SUNDAY NIGHT. GIVEN EXPECTED DEGREE OF CLOUDINESS ON BACK SIDE OF TROUGHING IN THE EAST...AND WIND FLOW OFF OF LAKE HURON...IT WILL DIFFICULT TO GENERATE ANY WIDESPREAD CLEARING OR FROST THIS WEEKEND. MONDAY THROUGH FRIDAY... 12Z RUNS CONTINUE TO DEPICT CONSENSUS OF 500 MB SHORTWAVE TROUGHING LIFTING NORTHEAST OUT OF THE LOWER MS VALLEY INTO SOUTHERN LAKES REGION BY MONDAY AHEAD OF CLOSED SOUTHWESTERN USA LOW...FOLLOWED BY SHORTWAVE RIDGING WHICH SHOULD SET UP AHEAD OF WESTERN LOW/TROUGH COMPLEX AT LEAST BY WEDNESDAY...A LITTLE EARLIER VIA 00Z/12Z WRFXX...06Z DGEX...00Z GLOBAL. THEN...THE WESTERN SYSTEM MOVES IN AFTER MID WEEK TO BRING UNSETTLEDNESS/MOISTURE TO FORECAST AREA. AT THE SURFACE...INVERTED TROUGHINESS CONTINUING TO PUNCH NORTHWARD INTO EASTERN LAKES REGION AND INTO BROAD RIDGE TO THE NORTH EARLY IN WEEK. SOME SORT OF TROUGH OR FRONT MOVING IN FOR LATTER PART OF WEEK AS PER MODEL CONSENSUS. BY MONDAY...GOOD MODEL CONSENSUS SHOWING RELATIVELY DEEP MOISTURE IN PLACE...WEAK LOW TO MID LEVEL OMEGA LIFT...WEAK 850 TO 700 MB THETA E RIDGE BULGING INTO AT LEAST EASTERN COUNTIES FROM THE EAST/SOUTHEAST... MODEST SURFACE CONVERGENCE WITH A LITTLE UPPER LEVEL DIVERGENCE TO BOOT...AND WEAK 305K ISENTROPIC ASCENT WITH LOWERING CONDENSATION PRESSURE DEFICITS. WILL INTRODUCE CHANCE SHOWERS FOR MONDAY THROUGH TUESDAY TIME FRAME EASTERN COUNTIES OF FORECAST AREA...AND MAY HAVE TO LATER EXPAND WEST IF LATER MODEL RUNS CONFIRM RECENT TRENDS. AS BEFORE...CHANCE POPS WEDNESDAY NIGHT AND THURSDAY...WHICH WILL BE CONTINUED THROUGH FRIDAY. GUIDANCE TEMPERATURES APPEAR TO BE IN THE BALL PARK. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...SMALL CRAFT ADVISORY...NEARSHORE WATERS FROM PORT AUSTIN TO PORT HURON AND ALSO FOR SAGINAW BAY...UNTIL 6 AM SUNDAY. LAKE ST CLAIR...SMALL CRAFT ADVISORY...LCZ460...UNTIL 6 AM SATURDAY. MI WATERS OF LAKE ERIE...SMALL CRAFT ADVISORY...LEZ444...UNTIL 6 AM SUNDAY. && $$ SHORT TERM...BGM LONG TERM....DWD AVIATION.....DG mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 335 PM EDT FRI OCT 7 2005 .SHORT TERM...TONIGHT AND SATURDAY A BLOCKY AND MESSY UPPER PATTERN ACROSS NOAM WITH TROPICAL REMNANTS PLAGUING THE EASTERN SEABOARD AND PACIFIC JET INFLUX ENTERING THE PACIFIC NORTHWEST. A NOTABLE SHORT WAVE, WITH NOT MUCH MOISTURE AND NO RADAR RETURNS, WAS SLOWLY PROGRESSING ACROSS ILLINOIS AND WITH THE ASSISTANCE OF 100+ 300MB JET ENTRANCE REGION OVERHEAD PROVIDING ENOUGH LIFT FOR CLOUD DEVELOPMENT. ON THE MESOSCALE...BANDS OF STRATUS UNDER THE AC/CS CONTINUE TO COME IN OFF OF LAKE HURON YET NO REPORTS OF PRECIP FROM SURROUNDING RADAR SITES AND OBSERVATIONS. COOL NORTHEAST GRADIENT FLOW WILL DOMINATE THROUGH THE SHORT TERM PERIOD. FOR TONIGHT...BOTH THE NAM AND GFS AGREE WITH SYNOPTIC SCALE SETTING UP OVERNIGHT AS SURFACE HIGH SLIDES ACROSS THE NORTHERN LAKES AND WAVES OF LOW PRESSURE TRACK UP THE EASTERN STATE. THIS WILL PROLONG THE EASTERLY FETCH OFF THE WARM WATERS OF LAKE HURON WITH INVERSION HEIGHTS SLOWLY FALLING THRU THE NIGHT. YET MODELS TEND TO CRASH THESE HEIGHTS TOO SOON AND LOOKING CLOSER AT THE RUC13 AND OTHER EXPERIMENTAL RUNS OF THE RUC/WRF...CONVERGENCE INCREASES OVERNIGHT OVER LAKE HURON INTO SAGINAW BAY WITH EVEN SOME HINT OF LIGHT QPF DEVELOPING INTO THE TRI CITIES REGION AND PORTIONS OF THE THUMB. THIS MIGHT BE THE RESULT OF A MORE CLEARING TREND UPSTREAM AND LAND BREEZE DEVELOPMENT TO ENHANCE CONVERGENCE FIELDS SOMEWHAT. THEREFORE, WE WILL INTRODUCE A CHANCE FOR SOME SPRINKLES FOR THOSE COUNTIES NORTH OF I69 AND EAST OF I75. OTHERWISE, WITH IMPRESSIVE INVERSION SETTING UP OVERNIGHT, LAKE STRATUS WILL LIKELY HOLD ON THROUGH MOST OF THE NIGHT. WITH AFOREMENTIONED SHORT WAVE APPROACHING...MODELS ARE CONSISTENT WITH Q-VECTOR CONVERGENCE THIS EVENING BUT LIMITED MOISTURE ALOFT SHOULD PROHIBIT ANY MENTION OF PRECIP. HEADING INTO SATURDAY ALL AVAILABLE GUIDANCE SUGGESTS THIS SHORT WAVE BECOMES STRUNG OUT AND WEAKENS EITHER OVER OR JUST SOUTHEAST OF THE STATE. EITHER WAY, THIS SHOULD INCREASE SUBSIDENCE FURTHER AND DRIER AIR UPSTREAM WILL BEGIN TO INFILTRATE NORTHERN LAKE HURON AND ASSIST WITH THE BREAK UP OF LAKE STRATUS CLOUDS. SO WE MIGHT START OFF WITH MORE CLOUDS BUT TRANSITION TOWARD MORE SUNSHINE THROUGH THE DAY...PTSUNNY FORECAST! MET NUMBERS LOOK TOO LOW AND LIKELY DUE TO MODELS' HIGH LOW LEVEL MOISTURE CONTENT AND CLOUD COVER. WE WILL SHADE CLOSER TO THE MAV/FWC NUMBERS. && .LONG TERM...SATURDAY NIGHT THROUGH FRIDAY SATURDAY NIGHT THROUGH SUNDAY NIGHT... SURFACE RIDGE OVER WESTERN GREAT LAKES REGION PRETTY MUCH HELD AT BAY THROUGH THE WEEKEND AS TROUGHING KEEPS REAFFIRMING ITSELF IN THE EAST. AT 500 MB...EARLIER WEAKENED SHORTWAVE TROUGH STILL WOBBLING AROUND VICINITY OF SOUTHEAST MI SATURDAY NIGHT AND SUNDAY. STILL CALLING FOR A RATHER TRANQUIL FORECAST FOR THIS TIME FRAME...WITH LITTLE OR NO SYNOPTIC SCALE LIFT. 850 TO 500 MB RELATIVE HUMIDITY RATHER DRY THROUGH SUNDAY...THEN INCREASING MOISTURE WORKING BACK IN SUNDAY NIGHT. 925 MB MOISTURE...IN MOIST NORTHEAST FLOW...A LITTLE BETTER...THOUGH EVEN THIS INCREASES SUNDAY NIGHT. GIVEN EXPECTED DEGREE OF CLOUDINESS ON BACK SIDE OF TROUGHING IN THE EAST...AND WIND FLOW OFF OF LAKE HURON...IT WILL DIFFICULT TO GENERATE ANY WIDESPREAD CLEARING OR FROST THIS WEEKEND. MONDAY THROUGH FRIDAY... 12Z RUNS CONTINUE TO DEPICT CONSENSUS OF 500 MB SHORTWAVE TROUGHING LIFTING NORTHEAST OUT OF THE LOWER MS VALLEY INTO SOUTHERN LAKES REGION BY MONDAY AHEAD OF CLOSED SOUTHWESTERN USA LOW...FOLLOWED BY SHORTWAVE RIDGING WHICH SHOULD SET UP AHEAD OF WESTERN LOW/TROUGH COMPLEX AT LEAST BY WEDNESDAY...A LITTLE EARLIER VIA 00Z/12Z WRFXX...06Z DGEX...00Z GLOBAL. THEN...THE WESTERN SYSTEM MOVES IN AFTER MID WEEK TO BRING UNSETTLEDNESS/MOISTURE TO FORECAST AREA. AT THE SURFACE...INVERTED TROUGHINESS CONTINUING TO PUNCH NORTHWARD INTO EASTERN LAKES REGION AND INTO BROAD RIDGE TO THE NORTH EARLY IN WEEK. SOME SORT OF TROUGH OR FRONT MOVING IN FOR LATTER PART OF WEEK AS PER MODEL CONSENSUS. BY MONDAY...GOOD MODEL CONSENSUS SHOWING RELATIVELY DEEP MOISTURE IN PLACE...WEAK LOW TO MID LEVEL OMEGA LIFT...WEAK 850 TO 700 MB THETA E RIDGE BULGING INTO AT LEAST EASTERN COUNTIES FROM THE EAST/SOUTHEAST... MODEST SURFACE CONVERGENCE WITH A LITTLE UPPER LEVEL DIVERGENCE TO BOOT...AND WEAK 305K ISENTROPIC ASCENT WITH LOWERING CONDENSATION PRESSURE DEFICITS. WILL INTRODUCE CHANCE SHOWERS FOR MONDAY THROUGH TUESDAY TIME FRAME EASTERN COUNTIES OF FORECAST AREA...AND MAY HAVE TO LATER EXPAND WEST IF LATER MODEL RUNS CONFIRM RECENT TRENDS. AS BEFORE...CHANCE POPS WEDNESDAY NIGHT AND THURSDAY...WHICH WILL BE CONTINUED THROUGH FRIDAY. GUIDANCE TEMPERATURES APPEAR TO BE IN THE BALL PARK. && .AVIATION...ISSUED 100 PM EDT FRI MVFR CONDITIONS WILL PREVAIL THANKS TO COLD NORTHEAST FLOW AND LAKE STRATUS ALONG WITH DIURNAL COMPONENT TO KEEP THESE CEILINGS NEARLY CONSTANT. AS NIGHTTIME APPROACHES...INVERSION STRENGTHENS AND WE JUST MIGHT KEEP THIS STRATUS LAYER GOING FOR A WHILE. AS SOME SUBSIDENCE ACROSS THE NORTH COUNTRY TAKES SHAPE OVERNIGHT WE SHOULD SEE ENOUGH BREAKS IN THE CLOUD COVER AS MOISTURE DECREASES ACROSS THE NORTHERN HALF OF LAKE HURON. NORTHEAST WIND TRAJECTORIES WILL PREVAIL THRU THE TAF PERIOD FOR ALL SITES. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...SMALL CRAFT ADVISORY...NEARSHORE WATERS FROM PORT AUSTIN TO PORT HURON AND ALSO FOR SAGINAW BAY...UNTIL 6 AM SUNDAY. LAKE ST CLAIR...SMALL CRAFT ADVISORY...LCZ460...UNTIL 6 AM SATURDAY. MI WATERS OF LAKE ERIE...SMALL CRAFT ADVISORY...LEZ444...UNTIL 6 AM SUNDAY. && $$ SHORT TERM...BGM LONG TERM....DWD AVIATION...BGM mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 325 PM EDT FRI OCT 7 2005 .DISCUSSION... MAIN FCST PROBLEM REVOLVES AROUND CLOUDS AND TEMPS TONIGHT. WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW WRLY FLOW INTO THE PACIFIC NW WITH A FAIRLY WELL-DEFINED SHORTWAVE HEADING THRU SRN SASKATCHEWAN. DOWNSTREAM...SHORTWAVE RIDGING IS OVER MANITOBA/WRN ONTARIO...WHICH IS SUPPORTING SFC HIGH PRES OVER WRN ONTARIO. RIDGE AXIS RUNS SSW FROM THERE TO NW IA AND CNTRL KS. MAJOR PROBLEM FOR TEMP FCST TONIGHT IS THE LOW-LEVEL MOISTURE TRAPPED BELOW INVERSION BASED BTWN 915 AND 850MB PER 12Z CWPL/KINL/KGRB/KAPX SOUNDINGS. CWPL SOUNDING IS PROBABLY REPRESENTATIVE OF THE LOW-LEVEL AIRMASS THAT WILL BE ROTATING ANTICYCLONICALLY SW INTO UPPER MI TONIGHT JUST AHEAD OF APPROACHING SFC HIGH PRES RIDGE. ALTHOUGH THE SOUNDING INDICATED THE SATURATED LAYER TO BE ONLY ABOUT 700FT THICK JUST BELOW BASE OF VERY SHARP INVERSION AT 875MB...VIS SATELLITE IMAGERY SHOWS DAYTIME HEATING HAS HAD MINIMAL IMPACT ON MIXING CLOUDS/MOISTURE OUT TODAY TO THE N AND NE OF LAKE SUPERIOR. CLOUDS HAVEN'T BECOME TOO CELLULAR IN APPEARANCE EITHER...SUGGESTING THEY MAY PERSIST THRU THE NIGHT. THE ONLY AREA WHERE CLEARING HAS REALLY TAKEN HOLD IS JUST E OF WHITEFISH BAY AND OVER FAR ERN CHIPPEWA/MACKINAC COUNTIES WHERE NRLY FLOW IS DOWNSLOPING OFF HIGHER TERRAIN. MEANWHILE...LAKE EFFECT PCPN HAS BEEN WINDING DOWN THRU THE AFTN DUE TO A COMBINATION OF MODERATING LOW-LEVEL TEMPS/INCREASING ANTICYCLONIC FLOW AND LOWERING INVERSION HEIGHTS. BASED ON RECENT TRENDS...WILL NEED TO EXTEND A MENTION OF SPRINKLES/FLURRIES INTO THE FIRST FEW HRS OF THE EVENING. WILL BE A DIFFICULT TEMP FCST TONIGHT DUE TO CLOUD COVER AS ALLUDED TO ABOVE. LAKE EFFECT CLOUDS WILL PERSIST SINCE TEMP AT BASE OF INVERSION ONLY RISES TO -1 OR -2C...BUT SINCE FLOW WILL BE VEERING FROM NERLY NOW TO ERLY DURING THE NIGHT...EXPECT LAKE EFFECT CLOUDS TO IMPACT EVENTUALLY ONLY THE AREAS FROM THE HURON MOUNTAINS TO THE KEWEENAW. HOWEVER...THE MASS OF STRATOCU THAT REMAINS TRAPPED BLO INVERSION TO THE N AND E OF LAKE SUPERIOR SUGGESTS CLOUDS MAY EVEN DOMINATE MUCH OF THE REST OF THE FCST AREA THRU THE NIGHT. LOW-LEVEL FLOW CERTAINLY BECOMES MORE ANTICYCLONIC AS SFC RIDGE AXIS MOVES TO WRN UPPER MI BY 12Z SAT...BUT THAT DOESN'T LOOK TO GUARANTEE CLEAR SKIES SINCE VIS SATELLITE IMAGERY SHOWED SEVERAL AREAS OF SCT/BKN CLOUD COVER JUST AFTER SUNRISE THIS MORNING WHERE RIDGE AXIS WAS LOCATED. SEEMS BEST POTENTIAL FOR SKIES TO CLEAR IS WHERE ERLY FLOW DOWNSLOPES. THAT WOULD FAVOR THE ERN FCST AREA (GENERALLY E OF A MUNISING TO ESCANABA LINE) AND AN AREA OVER FAR WRN UPPER MICHIGAN (WRN GOGEBIC COUNTY AND MOST OF ONTONAGON COUNTY). 950MB WINDS OVER THE E WILL RUN 15-20KT THRU THE NIGHT...SO COMPLETE DECOUPLING SEEMS UNLIKELY. DON'T EXPECT TEMPS TO FALL MUCH UNDER 30 IF AT ALL OVER THE INTERIOR E. THE FAR W WILL HAVE BEST OPPORTUNITY TO DECOUPLE COMPLETELY WITH ARRIVAL OF RIDGE AXIS. WILL KEEP MIN TEMPS THERE IN THE MID 20S. TEMPS OVER THE REST OF THE FCST AREA WILL VARY GREATLY DEPENDING ON AMOUNT OF CLEARING AT EACH LOCATION AND HOW LONG THE CLEARING LASTS. FOR NOW...WILL GO WITH TEMPS ONLY AS LOW AS AROUND 30 OVER THE INTERIOR CNTRL...BUT CAN EASILY SEE TEMPS STAYING ABOVE FREEZING OR PLUMMETING WELL DOWN INTO THE 20S DEPENDING ON CLOUD COVER. SO...HAVE OPTED TO ISSUE A FREEZE WARNING FOR ALL AREAS THAT CURRENTLY HAVE A FREEZE WATCH GIVEN THE EASY POTENTIAL TO FALL BLO FREEZING WHERE CLOUDS DO BREAK. BY THE WAY... TONIGHT IS THE LAST NIGHT FROST/FREEZE HEADLINES WILL BE ISSUED BY THIS OFFICE FOR THIS SEASON. TRANQUIL WEATHER WILL DOMINATE SAT THRU MON. SHORTWAVE HEADING THRU SASKATCHEWAN NOW WILL LIFT NE WELL TO THE NW OF HERE TONIGHT/SAT AS RIDGE BUILDS OVER THE CNTRL/ERN CONUS. RIDGE WILL THEN DOMINATE THE WEATHER HERE THRU MON. THERE WAS SOME CONCERN WITH MON FCST AS ENERGY OVER THE LWR MISSISSIPPI VALLEY MIGHT LIFT INTO THE LWR GREAT LAKES IN LARGER SCALE SSW FLOW TO THE E OF DEEPENING WRN TROF. HOWEVER...LATEST MODEL RUNS HAVE SHIFTED A LITTLE MORE SE WITH SYSTEM...SO DRY FCST REMAINS ON TRACK THRU MON. TEMPS WILL TREND UPWARD EACH OF THE NEXT FEW DAYS WITH SKY CONDITION TRENDING TOWARD CLEAR/MOSTLY CLEAR. SAT WILL HAVE THE MOST CLOUD COVER OF THE NEXT 3 DAYS DUE TO DIURNAL CU/STRATOCU. HAVE GONE CLOSER TO THE WARMER GFS MOS GUIDANCE SAT/SUN GIVEN GFS AGREEMENT WITH UKMET ON MODERATION OF LOW-LEVELS. SAT NIGHT WILL BE A CHILLY NIGHT WITH THE COMBINATION OF CLR SKIES/LGT WINDS ALLOWING FOR IDEAL RADIATIONAL COOLING. WILL KEEP TEMPS TOWARD THE LOWER GFS MOS GUIDANCE SAT NIGHT. TUE THRU FRI...CANADIAN/UKMET/ECMWF/GFS STILL REMAIN IN REASONABLE AGREEMENT ON THE PATTERN DURING THIS PERIOD. MAIN FCST ISSUES ARE PROGRESSION OF CUTOFF ENERGY OVER THE SRN ROCKIES EARLY IN THE WEEK THAT LIFTS NE INTO THE GREAT LAKES MIDWEEK...AND IMPACT OF NRN STREAM SHORTWAVE ON ITS HEALS. DRY FCST FOR TUE IS IN GOOD SHAPE WITH RIDGE LINGERING OVER THE UPPER LAKES. GIVEN THE GOOD AGREEMENT ON PROGRESSION OF SW SYSTEM...PLAN TO STAY WITH GOING LOW CHC POPS LATER WED/WED NIGHT AS THIS WEAKENING MID/UPPER LEVEL ENERGY ENCOUNTERS DRY AIR WHILE TRACKING NE INTO THE AREA. THEN THERE IS MORE DISAGREEMENT IN HOW STRONG NRN STREAM SHORTWAVE WILL BE AND WHAT KIND OF INTERACTION MAY TAKE PLACE WITH THE ENERGY LIFTING THRU THE GREAT LAKES. UKMET/CANADIAN SHOW SHARPER AMPLIFICATION OVER THE GREAT LAKES BY 00Z THU THAN THE ECMWF/GFS...THOUGH 12Z UKMET HAS BACKED OFF CONSIDERABLY. GIVEN HPC PREFERENCE...WILL LEAN TOWARD GFS/ECMWF SOLUTION. WILL CARRY THE LOW CHC POPS FROM WED NIGHT INTO THU AS MID LEVEL TROF PASSES. GFS INDICATES MORE SHORTWAVE ENERGY DROPPING INTO THE UPPER LAKES REGION ON FRI...AND THIS IS SUPPORTED BY GFS REFORECAST ENSEMBLE. SO...WILL CONTINUE WITH LOW CHC POPS ON FRI AS WELL. TEMPS THRU THE PERIOD SHOULD REMAIN ABOVE NORMAL...GENERALLY HIGHS IN THE UPPER 50S TO AROUND 60 WITH LOWS IN THE MID 30S TO LWR 40S. && .MQT...WATCHES/WARNINGS/ADVISORIES... FREEZE WARNING TONIGHT MIZ002>007-009>014-084-085. && $$ ROLFSON mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 1140 AM EDT FRI OCT 7 2005 .DISCUSSION... LK EFFECT PCPN MAIN CONCERN ALONG WITH MAX TEMPS LARGE SWATH OF STRATOCU FM N ONTARIO INTO LK SUPERIOR AND INTO NW/N WI. THIS MOISTURE EXTENDS THROUGH AROUND 5K FT PER 11Z TAMDAR SOUNDING FM CMX AND 00Z RAOB LAST EVENING AT KINL. TEMPS GRADUALLY WARM BY VERY LATE IN THE DAY WITHIN THE MIXED LAYER BUT UNTIL THEN TEMPS AT TOP OF INVERSION NEAR -6C GIVE A LAKE-H8 DELTA T VALUE AROUND 20C. DESPITE UNIDIRECTIONAL NE FLOW WITHIN MIXED LAYER NOT CHANGING MUCH IN LAST FEW HOURS...NOT MUCH IN WAY OF INDIVIDUAL LK PCPN BANDS. STILL...IN AREAS WHERE LOW LEVEL CONVERGENCE HAS BEEN MAXIMIZED (MARQUETTE TO MUNISING AND AROUND IRONWOOD IN FAR WEST) PCPN COVERAGE HAS BEEN ENHANCED. SUB 1000 FT AGL TEMPS AND LOCATION ELEVATION HAS BEEN CRITICAL FOR PTYPE THUS FAR. MOST OF THE PCPN NEAR MQT-P53 IS RAIN WITH TEMPS BTWN 39-41F WHILE OVR THE INTERIOR PORTIONS OF MQT COUNTY INTO THE FAR WEST ITS BEEN MOSTLY SNOW AS TEMPS HOVER JUST ABOVE FREEZING (33-36F). 2 INCH SOIL TEMP STILL 54F HERE AT NWS OFFICE IN NEGAUNEE TWP...AND THIS IS PROHIBITING ANY ACCUM ON THE GROUND THUS FAR. DID RECEIVE REPORT AROUND IRONWOOD OF AN INCH OF SNOW ACCUMULATING ON VEHICLES...BUT IT WAS HAVING A HARD TIME STICKING ON THE GROUND. OVERALL THE FORECAST IS IN GOOD SHAPE. DELAYED THE ENDING OF LK PCPN OVR THE TWO CONVERGENCE AREAS AS LOWER LAYERS REMAIN QUITE MOIST THROUGH THE AFTN. SC HAS FILLED IN OVR MOST AREAS. PERSISTENT N FLOW MAY HELP DOWNSLOPE INTO FAR SCNTRL AREAS. AS PCPN/CLOUDS HANG ON THROUGH MUCH OF AFTN TEMPS WILL STRUGGLE SINCE FLOW IS OFF LK SUPERIOR. HOWEVER...TEMPS MAY TRY TO BOUNCE UP LATE TODAY AS RUC/NAM INDICATE RISING TEMPS IN THE 925-900MB LEVELS LATE AS HEIGHTS BEGIN RISING. CONCERN FOR TONIGHT IS EXTENT OF LOWER LEVEL CLOUDS UPSTREAM. LATEST NAM INDICATED THAT EXCEPT FOR THE FAR EAST PARTLY TO MOSTLY CLOUDY SKIES MAY PERSIST FOR MOST AREAS THROUGH MUCH OF NIGHT. OBVIOUSLY...THIS WOULD HAVE BIG IMPACT ON GOING MINS FORECASTED FM MID 20S TO AROUND 30 WITH TEMPS LIKELY AOA FREEZING IF MORE CLOUDS STICK AROUND. WILL BE FOCUSING ON THIS IN AFTN PACKAGE...BUT MADE NO CHANGES TO FREEZE WATCH ATTM. && .PREV DISCUSSION (ISSUED AT 325 AM EDT THIS MORNING)... UPR RDG FCST TO BLD OVER THE GRT LKS TNGT...WITH H925 FLOW BCMG INCRSGLY ACYC AND VEERING TO MORE E BY 12Z AS SFC HI CENTER PROGGED TO MOVE TOWARD JAMES BAY BY 12Z WED. THIS SCENARIO WOULD FAVOR MORE LK CLD OVER THE KEWEENAW/SRN MNM COUNTY WHILE DSPTG ELSEWHERE AS DRIER DOWNSLOPED AIR OVER THE E OFF ONTARIO ADVECTS TO THE W. ALTHOUGH THE LK AGGREGATE APPEARS TO MOISTEN THE INCOMING AIRMASS...WITH PWAT FCST TNGT ARND 0.40 INCH VS 0.30 INCH OR SO UPSTREAM...SETUP TNGT LOOKS IDEAL FOR IDEAL RADIATIONAL HEAT LOSS/WDSPRD FROST OR FREEZE AWAY FM LK MODERATION NR THE SHORES AND OVER THE KEWEENAW/SRN MNM COUNTY. HAVE OPTED TO POST A FREEZE WATCH FOR INLAND AREAS IN ALL COUNTIES EXCEPT KEWEENAW (THE SRN PART OF NORTHERN CMX COUNTY AND NRN MNM COUNTY WL SEE LTL LK MODERATION). BEST CHC TO SEE TMINS BLO MOS GUIDANCE WL BE OVER THE FAR W WHERE WIND SPEEDS WL BE LIGHTEST. CONCERNED THE PRES GRADIENT MIGHT REMAIN TIGHT ENUF TO MITIGATE TEMP DROP OVER THE E...BUT DAY SHIFT WL HAVE THE OPTION TO LOOK MORE CLOSELY AND NOT POST A WRNG IF NOT WARRANTED. SAT LOOKS TO BE A VERY PLEASANT FALL DAY UNDER BLDG UPR RDG/SFC RDG AXIS. ANY LINGERING LK SC WL DSPT WITH DAYTIME HTG/LOWERING INVRN. MIXING TO INVRN BASE AT H9 ON FCST GFS/NAM FCST SDNGS YIELDS TMAX NOT FAR FM 50. MOS/PRESENT FCST TEMPS COMPARE FVRBLY...SO LTL CHG NECESSARY. THE SHARPENING UPR RDG OVER THE UPR GRT LKS DOWNSTREAM OF A DEEPENING TROF OVER THE ROCKIES WL BRING A TRANQUIL PD FOR SAT NGT/SUN AS WELL. PREFER THE FLATTER PRES GRADIENT SHOWN BY THE 00Z GFS/UKMET/CNDN MODEL OVER THE SOMEWHAT SHARPER PRES GRADIENT DEPICTED BY THE NAM. THE COMBINATION OF CLR SKIES/LGT WINDS WL ONCE AGAIN ALLOW FOR IDEAL RADIATIONAL COOLING SAT NGT. WL HEDGE TOWARD LWR GFS MOS FCST TEMPS FOR SAT NGT TMINS. MIXING TO INVRN BASE ARND H9 ON THE GFS FCST SDNGS FOR SUN SHOWS HI TEMPS IN THE 55 TO 60 RANGE...VERY CLOSE TO GFS MOS AND GOING FCST. SOME UNCERTAINTY CREEPS INTO FCST FOR MON AS SOME MODELS SHOW AN UPR LO DRIFTING N THRU THE OH VALLEY AND INTO THE LWR GRT LKS IN LARGER SCALE SSW FLOW TO THE E OF DEEPENING WRN TROF. BUT EVEN THIS GUIDANCE SUGS THE DEEPER MSTR WL STAY TO THE SE OF THE FA...SO LTL CHC FOR PCPN. NO CHGS MADE TO FCST BEYOND SUN. COORDINATED WITH APX/GRB/DLH. && .MQT...WATCHES/WARNINGS/ADVISORIES...FREEZE WATCH LATE TNGT/EARLY SAT && $$ DISCUSSION...JLA PREV DISCUSSION..KC mi AREA FORECAST DISCUSSION...UPDATED AVIATION NATIONAL WEATHER SERVICE SPRINGFIELD MO 515 AM CDT FRI OCT 7 2005 .DISCUSSION... UPPER TROUGH UPSTREAM HAS TOUCHED OFF SOME LIGHT SHOWERS OR SPRINKLES ACROSS PARTS OF KANSAS AND OKLAHOMA EARLY THIS MORNING. HOWEVER...LOOKING AT THE 00Z KSGF SOUNDING A VERY DRY LAYER EXISTS FROM ROUGHLY 900MB TO 750MB. RUC AND NAM POINT SOUNDINGS DON'T MOISTEN THIS LAYER UP MUCH THIS MORNING. WITH THIS IN MIND...WILL KEEP GRIDS DRY FOR TODAY FOR MOST LOCATIONS...BUT MAY ADD SOME SPRINKLES TO THE GRIDS SOUTHWEST OF SGF THIS MORNING. SKIES SHOULD BECOME MOSTLY SUNNY ACROSS AT LEAST THE NORTHWEST HALF OF THE FORECAST AREA TOWARD EARLY AFTERNOON. TWEAKED HIGHS DOWN A BIT IN THE GRIDS FOR TODAY WITH READINGS GENERALLY TOPPING OUT IN THE UPPER 50S TO NEAR 60 WHICH TRENDS CLOSER TO THE MET GUIDANCE. NEXT CONCERN WILL DEAL WITH FROST POTENTIAL TONIGHT. WINDS WILL BECOME LIGHT ACROSS THE FORECAST AREA AS THE SURFACE RIDGE EDGES TOWARD EASTERN KANSAS BY 12Z SATURDAY. GENERALLY GOING WITH MIDDLE 30S ACROSS THE AREA OVERNIGHT...AND CONTINUED PATCHY FROST WORDING IN THE ZONES. MUCH OF THE AREA WILL HAVE CLEAR SKIES BUT MODELS ARE HINTING AT SOME POSSIBLE LOWER CLOUDS ADVECTING IN FROM THE EAST ACROSS CENTRAL MISSOURI. DUE TO THE UNCERTAINTY OF HOW FAR WEST THESE CLOUDS WILL BE...ALONG WITH SURFACE DEWPOINT TRENDS...DECIDED TO LET THE DAY SHIFT EVALUATE THE NEED FOR A POSSIBLE FROST ADVISORY EARLY SATURDAY MORNING. TEMPERATURES SHOULD WARM A BIT DURING THE DAY SATURDAY WITH HIGHS GENERALLY IN THE LOWER TO MIDDLE 60S. WITH WARM AIR ADVECTION FINALLY KICKING BACK IN ON SUNDAY...LOWER 70S WILL RETURN TO EASTERN KANSAS AND FAR WESTERN MISSOURI. AS FOR FROST POTENTIAL EARLY SUNDAY MORNING...RIDGE AXIS WILL STRETCH ACROSS THE EASTERN HALF OF THE FORECAST AREA. AFOREMENTIONED CLOUDS MAY BE OVER THIS AREA THOUGH...SO FOR NOW DO NOT HAVE ANY FROST IN THE FORECAST WHICH MESHES WELL WITH SURROUNDING WFOS. DIDN'T CHANGE MUCH WITH THE REMAINDER OF THE FORECAST. HELD ON TO LOW POPS OVER WESTERN LOCATIONS MONDAY NIGHT THROUGH TUESDAY NIGHT AS A SYSTEM TAKES SHAPE OVER THE PLAINS...DURING THIS PERIOD THE BETTER MOISTURE AXIS LOOKS TO STAY WEST OF THE FORECAST AREA. LATER SHIFTS MAY NEED TO ADD SOME POPS ON WEDNESDAY IF THE LATEST GFS VERIFIES...AS ITS SOLUTION BRING A SURFACE FRONT AND UPPER TROUGH THROUGH THE REGION. SAW && .AVIATION... FOR THE 12Z TAFS...SKY REMAINS OVERCAST BUT FAIRLY HIGH CEILINGS AT AROUND 9000 FEET AHEAD OF STRONG SHORTWAVE. ECHOES SHOWING UP ON KSGF RADAR BUT MUCH OF THIS NOT REACHING THE GROUND OR FALLING AS SPRINKLES. HAVE OPTED TO LEAVE ANY PRECIPITATION MENTION OUT OF 12Z TAFS. AS SHORTWAVE PUSHES SOUTHEAST THROUGH THE AREA...SKY SHOULD CLEAR FROM THE WEST. WINDS SHOULD GO LIGHT AND VARIABLE TONIGHT AS HIGH PRESSURE SETTLES IN AT THE SURFACE. LINDENBERG && SGF WATCHES/WARNINGS/ADVISORIES... .MO...NONE. .KS...NONE. $$ WFO SGF mo AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BINGHAMTON NY 305 PM EDT FRI OCT 7 2005 .SHORT TERM...(TONIGHT THRU SATURDAY) COMPLEX HEAVY RAIN EVENT UNFOLDING WITH SFC COLD FRONT JUST INSIDE OUR CWA THIS AFTERNOON. UL JET POISED TO OUR NORTH...AND LLVL JET OF 30-40 KTS SURGING DEEPER TROPICAL MOISTURE NWD ACROSS CNTRL PA AHEAD OF ENHANCED UL WAVE. RIGHT NOW...NAM/GFS AND RUC ARE IN DECENT AGREEMENT ON SLIGHT SEWD MOVEMENT OF FRONTAL BNDRY TONIGHT WITH WAVE AND LLJ LIFTING OUT TO OUR NE. SLUG OF MDT TO HVY RAIN WILL TARGET OUR ZONES WEST OF I-81 WITH ABOUT 2" OF RAIN TONIGHT...WITH BULK OF THAT FALLING NOW THRU MIDNIGHT. REST OF AREA STILL STANDS TO PICK UP 1-2". DISCREPANCIES IN MDL SOLUTIONS START TO SHOW UP SATURDAY...AND PARTICULARLY INTO SAT NITE WITH GFS PROGRESSIVELY MOVING FRONT TO OUR SOUTHEASTERN ZONES...WHILE NAM IS HOLDING BACK SLIGHTLY FURTHER WEST. CURRENTLY...WE FEEL THE NAM IS VERIFYING THE SYNOPTIC SETUP BEST THRU 18Z...AND OUR FCSTS WILL LEAN MORE WITH IT/S SCENARIO. A SSWLY FLOW ALOFT WILL KEEP MOISTURE STREAMING INTO THE SLOPED FRONTAL SYSTEM WITH RAIN THRU SAT FOR MOST OF THE AREA. IT DOES APPEAR THAT THE FOCUS FOR ANY KIND OF HEAVIER PCPN WILL SHIFT SLIGHTLY TO OUR ZONES ALONG...SOUTH AND EAST OF I-81 AND I-88 WHERE BEST LLVL CONVG SETS UP. AN ADDITIONAL 1-2" ACCUMULATION IS LIKELY THESE AREAS. WEST ACROSS THE SRN TIER AND FINGER LAKES BEHIND THE FRONT...STEADY PRECIP IS EXPECTED TO DWINDLE TO OCNL SHOWERS...AND UP TO ANOTHER INCH OF RAIN THRU THE DAY. TEMPERATURES VERY TRICKY WITH GOOD GRADIENT ACROSS COLD FRONT. LOWS DIPPING TO THE UPR 40S-LOW 50S XTRM N-W PART OF AREA WITH LOW-MID 60S POCONOS-WY/LACK VALLEYS OF NEPA TONIGHT...WITH LITTLE DIURNAL REBOUND SATURDAY. -JAB && .LONG TERM (SAT NGT - SATURDAY)... STILL MODEL DIFFERENCES IN THE SAT TO SUN PERIOD WITH GFS ALONE IN PUSHING COLD FRONT TO COAST. OTHER MODELS HAVE ANOTHER LOW MOVING UP THE COAST SAT NGT INTO SUN NGT KEEPING THE SOUTH TO NORTH FRONT OVER CWA. THIS DIFFERENCE HAS MAJOR REPERCUSSIONS IN ALL THE GRIDS. WE ARE GOING WITH THE CONSENSUS AND THE NAM. THIS MEANS THE START OF THE EXTENDED WILL BE WETTER AND WARMER THAN PREVIOUS RUNS AND GRIDS. 500 MB HEIGHTS SIMILAR WITH DIGGING WRN US TROF AND ERN US RIDGE. SHORT WAVE MOVES NE INTO OHIO VALLEY SUN NGT. NAM MOS HAS CATEGORICAL POPS SAT NGT INTO SUN NGT. WILL TAPER POPS OFF FROM CAT SAT NGT TO CHC SUN NGT. ALSO POPS TAPERED FROM LOW IN NW TO HIGH IN SE. PRECIP AMOUNTS ALSO TAPERED FROM LIGHT IN NW TO HEAVY IN SE. QPF LIGHTER THAN THE AMOUNTS IN THE NEXT 24 HOURS. FOR THE REST OF THE EXTENDED FROM TUESDAY ON STILL UNCERTAINTY WITH FRONTAL BOUNDARY NOT MOVING MUCH TO THE SE. SLOW MOVING WAVES CONTINUE ALONG FRONT. QUESTION ALSO HOW MUCH UL TROF IN WEST LIFTS AND FILLS AS IT MOVES E. MODELS GENERALLY AGREE ON UL HEIGHTS BECOMING MORE ZONAL BY NEXT WEEKEND. A WEAK TROF COULD BRING SOME SHOWERS FRIDAY BUT FOR NOW...WILL KEEP IT DRY FROM WEDNESDAY ON WITH FRONT TO COAST WED. FOR THIS PERIOD HAVE GONE WITH HPC GRIDS. -TAC && .AVIATION (07/18Z - 08/18Z)... FOR THE MOST PART...FLIGHT CONDITIONS WILL GENERALLY REMAIN IFR CIG/VSBY THRU THE PERIOD WITH MDT TO HVY RAIN WITH OCNL FLUXES BETWEEN LIFR AND MVFR PSBL. WINDS GRDLY VEERING FROM E-SE TO N-NW BY 13Z ACROSS THE AREA. LLVL WIND SHEAR PSBLY DVLPG...ESPLY AT AVP...THIS EVENING AS CORE OF 2000-4000 FT 30-40 KT WINDS MOVE OVER THE AREA. -JAB .HYDROLOGY... BASED ON THE PRESUMPTION THAT NAM RAIN FCSTS APPEAR MORE CORRECT THAN GFS...STORM RAINFALL TOTALS IN THE NEXT 48 HOURS EXPECTED TO RANGE FROM 3-5 INCHES ACROSS ALL BASINS. LOCAL SMALL STREAM AND URBANIZED FLOOD PROBLEMS POSSIBLE IN BANDS OF HEAVY RAIN...BUT MAIN STEM RIVERS EXPECTED TO ONLY SEE WITHIN BANK RISES. WITH ADDL HVY RAIN PSBL SAT NITE...HAVE EXTENDED FLOOD WATCH TO NOON SUNDAY. -JAB && .BGM WATCHES/WARNINGS/ADVISORIES... .NY...FLOOD WATCH...ALL COUNTIES...EXTENDED TONIGHT THRU NOON SUNDAY. .PA...FLOOD WATCH...ALL COUNTIES...EXTENDED TONIGHT THRU NOON SUNDAY. $$ ny AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON NC 940 PM EDT FRI OCT 7 2005 .SHORT TERM (OVERNIGHT/FLOOD POTENTIAL)... NO ZONE UPDATE IS PLANNED AT THIS TIME. THERE HAS BEEN A WELCOME RELATIVE LULL IN THE RAINFALL ACROSS THE AREA OVER THE LAST FEW HOURS. IT DOES APPEAR THOUGH THAT ONE MORE ROUND OF HEAVY RAIN IS IN STORE FOR THE REGION DURING THE OVERNIGHT HOURS. A LOW TO MID LEVEL JET IS ROUNDING THE EAST SIDE OF THE LOW OVER THE FL PANHANDLE. LARGE SCALE ASCENT ASSOC WITH THIS FEATURE IS CAUSING CONVECTION TO BLOSSOM EAST OF FLORIDA. SAT IMAGERY SHOWS THAT IT WILL BE HEADED RIGHT FOR THE CAPE FEAR REGION. GFS HAS BEEN DOING QUITE WELL WITH THE MOISTURE AND TAKEN LITERALLY IT WOULD SUGGEST THAT THE VERY BEST CHANCE FOR HEAVY RAIN WILL BE CONFINED TO COASTAL COUNTIES...PERHAPS THE NC COASTAL COUNTIES MORESO THAN THE SC COUNTIES. FLOOD WATCH WILL STAY AS IS THOUGH SINCE THE GROUND IS SO SATURATED THAT EVEN A LITTLE RAINFALL INLAND COULD LEAD TO MORE FLOODING ISSUES. LOW LEVEL FLOW SHOULD BE BACKED ENOUGH TO THE SOUTH TO CHANNEL THE DEEP MOISTURE TO THE EAST BY DAYBREAK SATURDAY. HOPEFULLY THE FLOOD WATCH WILL NOT NEED TO BE EXTENDED BEYOND ITS EXPIRATION TIME (ONCE AGAIN...MAYBE IN THE NC COASTAL COUNTIES). && .AVIATION... HAVE LARGELY CARRIED ON TRENDS FROM TODAY IN AT LEAST THE COASTAL TERMINALS AS SHOWERS CONTINUE TO STREAM ONSHORE IN A DEEP AND JUICY SSE FEED. TOO DIFFICULT TO TIME THE INDIVIDUAL POCKETS OF PRECIP...AND EXPECT ADDITIONAL DEVELOPMENT OFFSHORE OVERNIGHT...SO I WENT WITH TEMPO GROUPS TO GO BETWEEN MVFR/VFR CIGS IN THE BREAKS...TO BORDERLINE MVFR/IFR CIG AND VIS IN THE PRECIP. SERIOUS DIPS INTO IFR WILL BE TOO BRIEF TO EVEN WARRANT A TEMPO. WILL MAINTAIN MVFR CIGS THRU THE LATTER HALF OF THE TAFS...WITH KFLO EVEN IMPROVING TO VFR IN THE AFTERNOON AS THE AXIS OF DEEPEST MOISTURE FINALLY SHIFTS EAST OF THE AREA. && .MARINE... WAVES OF SHOWERS CONTINUE TO ROLL NORTH ACROSS THE COASTAL WATERS THIS EVENING. SUSTAINED WINDS OUTSIDE SHOWERS ARE GENERALLY 15-20 KT...BUT DOWNDRAFTS IN THE CONVECTION ARE LIKELY PRODUCING GUSTS UPWARD OF 30 KNOTS AT TIMES...AS WELL AS LOCALLY HIGHER SEAS. THE NAM AND RUC MODELS BOTH INDICATE A LOW LEVEL JET ORGANIZING ACROSS THE COASTAL WATERS SOUTH AND EAST OF CAPE FEAR AROUND MIDNIGHT TONIGHT...THEN SLOWLY LIFTING NORTH ALONG ONSLOW BAY EARLY SATURDAY MORNING. THERE WILL LIKELY BE AN ENHANCEMENT OF CONVECTIVE ACTIVITY IN THIS JET...WHICH WILL LEAD TO AN INCREASE IN SURFACE WIND SPEEDS AND GUSTS AFTER MIDNIGHT. GUSTS COULD EXCEED 35 KNOTS WHICH MAY LEAD TO SPECIAL MARINE WARNINGS LATER TONIGHT. IT IS DEFINITELY NOT A NIGHT TO PLAN AN EXCURSION OFFSHORE. BUOY 41013 MAY HAVE SUSTAINED DAMAGE TO ITS WAVE SENSOR AS IT HAS ONLY REPORTED SEA HEIGHT ONE HOUR OUT OF THE PAST 24. LATEST WAVEWATCH FORECASTS AND DATA FROM BUOY 41004 (EAST OF CHS) INDICATE LITTLE CHANGE IS NEEDED TO OUR SEAS FORECAST TONIGHT...6 TO 9 FEET OFF SC AND 8 TO 11 FEET OFF NC - HIGHEST IN THE VICINITY OF FRYING PAN SHOALS. && .ILM WATCHES/WARNINGS/ADVISORIES... NC...FLOOD WATCH FOR NCZ087-096-097-099>101 UNTIL 6 AM SATURDAY. SC...FLOOD WATCH FOR SCZ017-023-024-032>034-039-046 UNTIL 6 AM SATURDAY. MARINE...SMALL CRAFT ADVISORY FOR AMZ250-252 UNTIL 3 AM SUNDAY. ...SMALL CRAFT ADVISORY FOR AMZ254-256 UNTIL 8 PM SATURDAY. && $$ SHORT TERM...MBB AVIATION...RAS MARINE...TRA nc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON OH 1012 PM EDT FRI OCT 7 2005 .SHORT TERM (OVERNIGHT)... SCT -SHRA DIMINISHING ACRS EASTERN 1/3 FCST AREA...AND EXPECT THIS TREND TO CONTINUE OVER NEXT FEW HOURS. MID LVL DEFORMATION AXIS IS WEAKENING AND UPR JET OVER NRN OHIO IS SHIFTING NORTH AND EAST AWAY FROM THE REGION. THICK SC DECK WILL HOLD ACRS MOST OF FCST AREA THRU NIGHT. BACK EDGE OF SC HAS REMAINED NEARLY STATIONARY OVER SE INDIANA SINCE LATE AFTERNOON...AND CURRENT 11-3.9 MICRON SAT SHWNG SC DECK STARTING TO SHIFT BACK WEST JUST A BIT. BNDRY LYR FLO WILL REMAIN FROM NE OVERNIGHT...SO EXPECT THIS TREND TO CONTINUE. WILL KEEP PCPN IN FCST THRU 04-06Z ACRS EASTERN FCST AREA...THEN DRY BEYOND. TEMPS ALSO NOT DROPPING AS FAST AS PREV THOUGHT...SO BUMPED UP MIN TEMPS A FEW DEG ENTIRE FCST AREA. UPDATE OUT...PREV DISCUSSION FOLLOWS. RYAN && .PREVIOUS DISCUSSION... (ISSUED 726 PM EDT FRI OCT 7 2005) AVIATION (00Z-24Z)... SCT -SHRA CONTINUE ALONG MID LVL DEFORMATION ZONE...AFFECTING AREAS ALONG AND EAST OF I-71. CIGS/VSBYS HAVE BEEN LOWER WITHIN -SHRA/DZ. CURRENT RUC INDCG DEFORMATION WILL WEAKEN OVER NEXT FEW HOURS...AND LIKEWISE SHOULD SEE -SHRA DIMINISH AT EASTERN TAF SITES BY 04Z. REMAINDER OF NIGHT EXPECTED TO BE DRY (OTHER THAN SOME PATCHY DZ)...EVEN AS STRONG S/WV APPCHS FROM WEST. LARGE SC DECK REMAINS ACRS MUCH OF FCST AREA WITH CLEAR SLOT JUST TO WEST OF KCVG/KDAY. NOT EXPECTING MUCH EROSION AT ALL TO SC DECK OVERNIGHT AS BNDRY LYR FLO REMAINS PREDOMINANTLY OUT OF THE NE. RECENT SAT IMAGES INDCG SC HAS BUILT BACK TO WEST A LITTLE BIT...WITH SC ASSOCD WITH S/WV MOVING ACRS ILLINOIS. SHOULD BE ABLE TO GET CIGS INTO VFR CAT AT KDAY FOR A PERIOD OVERNIGHT..AND POSSIBLY EVEN AT KCVG/KLUK. FURTHER EAST...MVFR CIGS WILL REMAIN THRU THE NIGHT. SC DECK WILL BE SLOW TO ERODE ON SAT...BEING DELAYED UNTIL PASSAGE OF S/WV. DO NOT EXPECT A RISE TO VFR CIGS UNTIL LAST SIX HOURS OF FCST PERIOD. OTHER THAN VSBY RESTRICTION ASSOCD WITH -SHRA THIS EVNG...WINDS HOLDING AROUND 10KTS SHOULD RESTRICT ANY FOG DVPMNT OVERNIGHT. RYAN (ISSUED 418 PM EDT FRI OCT 7 2005) SHORT TERM (TONIGHT THROUGH SUNDAY NIGHT)... PCPN ALONG I-71 CORRIDOR FROM ILN-CMH APPEARS ASSOCIATED WITH A DEFORMATION ZONE. THIS LIFT WORKS SLOWLY EASTWARD THIS EVENING AND EXPECT PCPN TO GRADUALLY WEAKEN AS THE NIGHT PROGRESSES. HIGHEST POPS WILL BE IN CENTRAL OH...WHERE PCPN WILL LINGER THE LONGEST. WESTERN COUNTIES MIGHT SEE A LITTLE CLEARING TONIGHT...SO MENTIONED PARTLY CLOUDY LATER, H5 S/W SWINGS ACROSS THE FA ON SATURDAY. THIS COMBINED WITH LOW LEVEL MOISTURE WILL BE ENOUGH FOR A SPRINKLE AT ANY LOCATION. CUTOFF LOW BEGINS TO LIFT OUT OF LOWER MISSISSIPPI VALLEY SUNDAY. H5 VORT FROM SAT REMAINS ACROSS THE FA AS IT IS CAUGHT BETWEEN SYSTEMS. COULDN'T RULE OUT A SPRINKLE HERE OR THERE AGAIN ON SUNDAY. FOR SUNDAY NIGHT NAM IS MORE AGGRESSIVE IN LIFTING PCPN INTO SOUTHERN PART OF FA. PREFER THE GFS SOLUTION WHICH IS MORE DISORGANIZED AND JUST GIVES SCATTERED SHOWERS. AS FOR TEMPERATURES...GENERALLY WENT WITH A BLEND OF GUIDANCE. SITES LONG TERM (MONDAY THROUGH FRIDAY)... WITH UPPER TROUGH CROSSING THE AREA ADDED CHANCE OF SHOWERS MONDAY. KEPT TUESDAY AND WEDNESDAY DRY WITH TROUGH LIFTING NORTHEAST. INTRODUCED CHANCE SHOWERS WEDNESDAY NIGHT THROUGH FRIDAY WITH ARRIVAL OF A MORE SIGNIFICANT UPPER TROUGH. EXPECT TEMPERATURES TO BE NEAR TO SLIGHTLY ABOVE NORMAL...THOUGH NOT QUITE AS WARM AS THE OPTIMISTIC MEX GUIDANCE. CONIGLIO && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ oh AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON OH 726 PM EDT FRI OCT 7 2005 .AVIATION (00Z-24Z)... SCT -SHRA CONTINUE ALONG MID LVL DEFORMATION ZONE...AFFECTING AREAS ALONG AND EAST OF I-71. CIGS/VSBYS HAVE BEEN LOWER WITHIN -SHRA/DZ. CURRENT RUC INDCG DEFORMATION WILL WEAKEN OVER NEXT FEW HOURS...AND LIKEWISE SHOULD SEE -SHRA DIMINISH AT EASTERN TAF SITES BY 04Z. REMAINDER OF NIGHT EXPECTED TO BE DRY (OTHER THAN SOME PATCHY DZ)...EVEN AS STRONG S/WV APPCHS FROM WEST. LARGE SC DECK REMAINS ACRS MUCH OF FCST AREA WITH CLEAR SLOT JUST TO WEST OF KCVG/KDAY. NOT EXPECTING MUCH EROSION AT ALL TO SC DECK OVERNIGHT AS BNDRY LYR FLO REMAINS PREDOMINANTLY OUT OF THE NE. RECENT SAT IMAGES INDCG SC HAS BUILT BACK TO WEST A LITTLE BIT...WITH SC ASSOCD WITH S/WV MOVING ACRS ILLINOIS. SHOULD BE ABLE TO GET CIGS INTO VFR CAT AT KDAY FOR A PERIOD OVERNIGHT..AND POSSIBLY EVEN AT KCVG/KLUK. FURTHER EAST...MVFR CIGS WILL REMAIN THRU THE NIGHT. SC DECK WILL BE SLOW TO ERODE ON SAT...BEING DELAYED UNTIL PASSAGE OF S/WV. DO NOT EXPECT A RISE TO VFR CIGS UNTIL LAST SIX HOURS OF FCST PERIOD. OTHER THAN VSBY RESTRICTION ASSOCD WITH -SHRA THIS EVNG...WINDS HOLDING AROUND 10KTS SHOULD RESTRICT ANY FOG DVPMNT OVERNIGHT. RYAN && .PREVIOUS DISCUSSION... (ISSUED 418 PM EDT FRI OCT 7 2005) SHORT TERM (TONIGHT THROUGH SUNDAY NIGHT)... PCPN ALONG I-71 CORRIDOR FROM ILN-CMH APPEARS ASSOCIATED WITH A DEFORMATION ZONE. THIS LIFT WORKS SLOWLY EASTWARD THIS EVENING AND EXPECT PCPN TO GRADUALLY WEAKEN AS THE NIGHT PROGRESSES. HIGHEST POPS WILL BE IN CENTRAL OH...WHERE PCPN WILL LINGER THE LONGEST. WESTERN COUNTIES MIGHT SEE A LITTLE CLEARING TONIGHT...SO MENTIONED PARTLY CLOUDY LATER, H5 S/W SWINGS ACROSS THE FA ON SATURDAY. THIS COMBINED WITH LOW LEVEL MOISTURE WILL BE ENOUGH FOR A SPRINKLE AT ANY LOCATION. CUTOFF LOW BEGINS TO LIFT OUT OF LOWER MISSISSIPPI VALLEY SUNDAY. H5 VORT FROM SAT REMAINS ACROSS THE FA AS IT IS CAUGHT BETWEEN SYSTEMS. COULDN'T RULE OUT A SPRINKLE HERE OR THERE AGAIN ON SUNDAY. FOR SUNDAY NIGHT NAM IS MORE AGGRESSIVE IN LIFTING PCPN INTO SOUTHERN PART OF FA. PREFER THE GFS SOLUTION WHICH IS MORE DISORGANIZED AND JUST GIVES SCATTERED SHOWERS. AS FOR TEMPERATURES...GENERALLY WENT WITH A BLEND OF GUIDANCE. SITES LONG TERM (MONDAY THROUGH FRIDAY)... WITH UPPER TROUGH CROSSING THE AREA ADDED CHANCE OF SHOWERS MONDAY. KEPT TUESDAY AND WEDNESDAY DRY WITH TROUGH LIFTING NORTHEAST. INTRODUCED CHANCE SHOWERS WEDNESDAY NIGHT THROUGH FRIDAY WITH ARRIVAL OF A MORE SIGNIFICANT UPPER TROUGH. EXPECT TEMPERATURES TO BE NEAR TO SLIGHTLY ABOVE NORMAL...THOUGH NOT QUITE AS WARM AS THE OPTIMISTIC MEX GUIDANCE. CONIGLIO && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ oh AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CHARLESTON SC 705 PM EDT FRI OCT 7 2005 .UPDATED PRODUCTS TO REMOVE TORNADO WATCH. PREVIOUS FORECAST DISCUSSION... .SHORT TERM /TONIGHT THROUGH SUNDAY /... COPIUS TROPICAL MOISTURE CONTINUES TO STREAM NORTHWWARD ACROSS SE GA AND SE SC. AN AREA OF LOW PRESSURE WAS MOVING INTO SC AND WILL INTERACT WITH AN OLD BOUNDARY DRAPED ACROSS THE INLAND COUNTIES. SATELLITE STARTING TO SHOW A MORE BREAKS IN THE CLOUD COVER. AREA BECOMING A LITTLE MORE UNSTABLE BASED ON LATEST RUC STABILITY PARAMETERS. CONVECTION COULD BECOME MORE ACTIVE DURING THE NEXT SEVERAL HOURS UNTIL WE LOSE THE AFTN HEATING. TORNADO WATCH REMAINS IN EFFECT FOR ALL OF MY SC COUNTIES AND SCREVEN... EFFINGHAM... CHATHAM AND BRYAN COUNTIES. HEAVY RAIN CONTINUES TO BE A STRONG POSSIBILITY FOR MUCH OF THE AREA. IN THE PAST 24 TO 48 HOURS...MANY AREAS HAVE RECEIVED 4 TO 8 INCHES OF RAIN...WITH A FEW PLACES MORE THAN 12 INCHES. IT WILL NOT TAKE MUCH RAIN TO CAUSE FLOODING. THEREFORE...WILL EXTEND THE FLOOD WATCH THROUGH 12Z SATURDAY. && .LONG TERM /SUNDAY THROUGH FRIDAY/...THE FRONTAL BOUNDARY CURRENTLY APPROACHING THE AREA WILL BE WITH US FOR SEVERAL DAYS INTO NEXT WEEK. IT IS EXPECTED TO STALL RIGHT ALONG THE COAST OR JUST OFFSHORE SUNDAY NIGHT AND MONDAY...WITH A FEW WAVES OF LOW PRESSURE MOVING UP IT. EXPECT THE BEST CONVERGENCE RIGHT ALONG THE COAST DURING THE PERIOD...THUS HAVE TAPERED CHANCE POPS FROM EAST TO WEST BASED ON THIS IDEA. HAVE BROUGHT MAX AND MIN TEMPS UP CONSIDERABLY THROUGH THE PERIOD DUE TO A MUCH SLOWER FROPA THAN PREVIOUSLY EXPECTED. && .AVIATION...YET ANOTHER CRUNCHY TAF FCST TODAY. A SMALL SFC LOW IS SLOWLY TRACKING NORTH THROUGH ERN GA AND SRN SC. THIS FEATURE IS ENHANCING BANDS OF CONVECTION OVER THE AREA...IN ADDITION TO WRAPPING SOME DRIER AIR INTO THE ERN FRINGE OF GA. WILL PROBABLY HAVE ANOTHER ROUND OF CONVECTION LATE THIS AFTERNOON INTO THE EVENING ESPECIALLY WHERE MORE INSTABILITY CAN DEVELOP. CIGS WILL PROBABLY GO VFR ACROSS MUCH OF THE AREA FOR A WHILE THIS EVENING BEFORE ANOTHER LOBE OF MOISTURE WRAPS AROUND THE LOW. HAVE TRIED TO TIME THE ROUNDS OF CONVECTION WITHOUT GETTING TOO CRAZY WITH TEMPOS. EXPECT SOME LOW VSBYS AND CIGS SAT MORNING BUT WITH THE PRECIP WINDING DOWN OVERNIGHT. && .MARINE...SEAS ARE SLOWLY FALLING THIS AFTERNOON DUE TO FAIRLY WEAK WIND FLOW ACROSS THE WATERS. SOME SWELL WILL CONTINUE TO AFFECT OUR NRN WATERS THROUGH TONIGHT AS WELL AS GA WATERS 20-60NM WHERE THE WINDS HAVE BEEN HIGHER. WILL TAKE DOWN THE SCA FOR HAZARDOUS SEAS AMZ354 SINCE BUOY 41008 REALLY HAS NOT SHOWN SEAS HIGHER THAN 5.5 FT FOR A FEW HRS. WILL LEAVE OTHER FLAGS UNCHANGED. WIND DIRECTIONS WILL BE TRICKY STARTING SUNDAY AS THE COLD FRONT APPROACHES FROM THE WEST AND EVENTUALLY STALLS OUT OVER THE WATERS EARLY NEXT WEEK. SPEEDS WILL BE RATHER LIGHT HOWEVER. && .RIP CURRENTS...PLAN ON A LOW RISK OF RIP CURRENTS BOTH SC AND GA BEACHES ON SATURDAY. ANY APPRECIABLE SWELL IS DECREASING BY THE HOUR AND THE WINDS WILL ONLY BE 10-15 MPH SLIGHTLY ONSHORE. DO NOT SEE ANY FACTORS THAT WOULD REQUIRE A MODERATE. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...FLOOD WATCH GAZ087-088-099>101-114>119-137>141. SC...FLOOD WATCH SCZ040-042>045-047>051. MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS AMZ350-352-354-374. && $$ 30/50 sc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CHARLESTON SC 230 PM EDT FRI OCT 7 2005 .SHORT TERM /TONIGHT THROUGH SUNDAY /... COPIUS TROPICAL MOISTURE CONTINUES TO STREAM NORTHWWARD ACROSS SE GA AND SE SC. AN AREA OF LOW PRESSURE WAS MOVING INTO SC AND WILL INTERACT WITH AN OLD BOUNDARY DRAPED ACROSS THE INLAND COUNTIES. SATELLITE STARTING TO SHOW A MORE BREAKS IN THE CLOUD COVER. AREA BECOMING A LITTLE MORE UNSTABLE BASED ON LATEST RUC STABILITY PARAMETERS. CONVECTION COULD BECOME MORE ACTIVE DURING THE NEXT SEVERAL HOURS UNTIL WE LOSE THE AFTN HEATING. TORNADO WATCH REMAINS IN EFFECT FOR ALL OF MY SC COUNTIES AND SCREVEN... EFFINGHAM... CHATHAM AND BRYAN COUNTIES. HEAVY RAIN CONTINUES TO BE A STRONG POSSIBILITY FOR MUCH OF THE AREA. IN THE PAST 24 TO 48 HOURS...MANY AREAS HAVE RECEIVED 4 TO 8 INCHES OF RAIN...WITH A FEW PLACES MORE THAN 12 INCHES. IT WILL NOT TAKE MUCH RAIN TO CAUSE FLOODING. THEREFORE...WILL EXTEND THE FLOOD WATCH THROUGH 12Z SATURDAY. && .LONG TERM /SUNDAY THROUGH FRIDAY/...THE FRONTAL BOUNDARY CURRENTLY APPROACHING THE AREA WILL BE WITH US FOR SEVERAL DAYS INTO NEXT WEEK. IT IS EXPECTED TO STALL RIGHT ALONG THE COAST OR JUST OFFSHORE SUNDAY NIGHT AND MONDAY...WITH A FEW WAVES OF LOW PRESSURE MOVING UP IT. EXPECT THE BEST CONVERGENCE RIGHT ALONG THE COAST DURING THE PERIOD...THUS HAVE TAPERED CHANCE POPS FROM EAST TO WEST BASED ON THIS IDEA. HAVE BROUGHT MAX AND MIN TEMPS UP CONSIDERABLY THROUGH THE PERIOD DUE TO A MUCH SLOWER FROPA THAN PREVIOUSLY EXPECTED. && .AVIATION...YET ANOTHER CRUNCHY TAF FCST TODAY. A SMALL SFC LOW IS SLOWLY TRACKING NORTH THROUGH ERN GA AND SRN SC. THIS FEATURE IS ENHANCING BANDS OF CONVECTION OVER THE AREA...IN ADDITION TO WRAPPING SOME DRIER AIR INTO THE ERN FRINGE OF GA. WILL PROBABLY HAVE ANOTHER ROUND OF CONVECTION LATE THIS AFTERNOON INTO THE EVENING ESPECIALLY WHERE MORE INSTABILITY CAN DEVELOP. CIGS WILL PROBABLY GO VFR ACROSS MUCH OF THE AREA FOR A WHILE THIS EVENING BEFORE ANOTHER LOBE OF MOISTURE WRAPS AROUND THE LOW. HAVE TRIED TO TIME THE ROUNDS OF CONVECTION WITHOUT GETTING TOO CRAZY WITH TEMPOS. EXPECT SOME LOW VSBYS AND CIGS SAT MORNING BUT WITH THE PRECIP WINDING DOWN OVERNIGHT. && .MARINE...SEAS ARE SLOWLY FALLING THIS AFTERNOON DUE TO FAIRLY WEAK WIND FLOW ACROSS THE WATERS. SOME SWELL WILL CONTINUE TO AFFECT OUR NRN WATERS THROUGH TONIGHT AS WELL AS GA WATERS 20-60NM WHERE THE WINDS HAVE BEEN HIGHER. WILL TAKE DOWN THE SCA FOR HAZARDOUS SEAS AMZ354 SINCE BUOY 41008 REALLY HAS NOT SHOWN SEAS HIGHER THAN 5.5 FT FOR A FEW HRS. WILL LEAVE OTHER FLAGS UNCHANGED. WIND DIRECTIONS WILL BE TRICKY STARTING SUNDAY AS THE COLD FRONT APPROACHES FROM THE WEST AND EVENTUALLY STALLS OUT OVER THE WATERS EARLY NEXT WEEK. SPEEDS WILL BE RATHER LIGHT HOWEVER. && .RIP CURRENTS...PLAN ON A LOW RISK OF RIP CURRENTS BOTH SC AND GA BEACHES ON SATURDAY. ANY APPRECIABLE SWELL IS DECREASING BY THE HOUR AND THE WINDS WILL ONLY BE 10-15 MPH SLIGHTLY ONSHORE. DO NOT SEE ANY FACTORS THAT WOULD REQUIRE A MODERATE. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...FLOOD WATCH GAZ087-088-099>101-114>119-137>141. TORNADO WATCH GAC029-051-103-251. SC...FLOOD WATCH SCZ040-042>045-047>051. TORNADO WATCH SCC005-013-015-019-029-035-049-053 MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS AMZ350-352-354-374. TORNADO WATCH AMZ330-350-352-354 && $$ 30/50 sc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SPOKANE WA 220 PM PDT FRI OCT 7 2005 .SYNOPSIS...A SERIES OF WEATHER DISTURBANCES WILL CARVE A TROUGH OF LOW PRESSURE OVER THE PACIFIC NORTHWEST THROUGH SATURDAY. THIS WILL RESULT IN COOL AND UNSETTLED WEATHER. HIGH PRESSURE WILL RETURN SUNDAY AND MONDAY FOR A DRYING TREND. ANOTHER WEAK WEATHER SYSTEM WILL TRACK ACROSS WASHINGTON LATE MONDAY INTO TUESDAY MORNING. THIS WILL BE FOLLOWED BY ZONAL FLOW THROUGH THE REMAINDER OF THE WEEK. && .DISCUSSION... TONIGHT THROUGH MONDAY...UPPER LEVEL TROUGH CONTINUES TO MOVE INTO THE REGION. MEANWHILE A SECONDARY LOW PRESSURE SYSTEM ON THE BACK OF THE TROUGH IS DIGGING SOUTH IN A 120+ KT NORTHERLY JET. THIS SCENARIO WAS INITIALIZED A LITTLE BETTER BY THE 12Z GFS THAN THE 12Z NAM AND FOR THE SHORT TERM FORECAST FOLLOWED THE GFS SOLUTION. THE GFS IS INDICATING A SPLIT FLOW OVER THE PACIFIC NORTHWEST WITH A WEAKER NORTHERN STREAM AND A MUCH STRONGER SOUTHERN STREAM RIDING THE JET MOVING INTO OREGON. THE TROUGH SLOWLY MOVES THROUGH THE REGION OVERNIGHT AND IS EXPECTED TO BE IN MONTANA AND IDAHO BY SATURDAY EVENING. THIS WILL BE FOLLOWED QUICKLY BY BUILDING HIGH PRESSURE ON SUNDAY WITH ANOTHER PACIFIC WEATHER SYSTEM KNOCKING ON THE DOOR BY MONDAY AFTERNOON. TONIGHT...KOTX 88D INDICATING SHOWERS CONTINUING TO MOVE THROUGH THE SOUTHERN IDAHO PANHANDLE AND ARE NOW DEVELOPING AGAIN OVER THE NORTHEAST ZONES. INSTABILITY PARAMETERS ARE NOT EXCESSIVE BUT THE 17Z RUC IS NOW SHOWING SURFACE BASED CAPES IN EXCESS OF 200J/KG ACROSS THE NORTHEAST ZONES. AS SUCH WILL CONTINUE WITH SHOWERS AND THUNDERSTORMS ACROSS THOSE ZONES THROUGH SUNSET. MEANWHILE A SHORT WAVE WILL TRACK ALONG THE BOTTOM OF THE TROUGH AND COMBINED WITH OROGRAPHIC LIFT WILL PROVIDE ENOUGH DYNAMICS TO CONTINUE SHOWERS ACROSS THE SOUTHEAST ZONES OVERNIGHT AS WELL. SNOW LEVELS NEAR 5000 FEET WILL RESULT IN THE POTENTIAL FOR LOCALIZED HIGH ELEVATION SNOW. EXPECT DECREASING WINDS AND SOME CLEARING OVERNIGHT AND COMBINED WITH LINGERING LOW LEVEL MOISTURE WILL PUT IN PATCHY FOG TO THE USUAL NORTHEAST VALLEY LOCATIONS. SATURDAY...WITH THE TROUGH PASSAGE HAVE KEPT OROGRAPHIC PRECIPITATION ACROSS THE SOUTHERN IDAHO PANAHNDLE AND THE CAMAS PRAIRIE FOR SATURDAY. ALSO KEPT CONVECTIVE SHOWERS ACROSS THE HIGHER TERRAIN OF THE NORTHERN MOUNTAIN ZONES AND SLOP OVER PRECIPITATION ACROSS THE CASCADE CREST. OTHERWISE THE MAJORITY OF THE FORECAST AREA WILL SEE DRYING CONDITIONS. TEMPERATURES WILL REMAIN BELOW SEASONAL NORMALS. SATURDAY NIGHT AND SUNDAY...HIGH PRESSURE BEGINS TO MIGRATE EASTWARD TOWARDS THE PACIFIC NORTHWEST SATURDAY AND MOVES INLAND ON SUNDAY. WILL HOLD ONTO SOME MOUNTAIN SHOWERS SATURDAY EVENING ACROSS IDAHO ZONE 4 IN THE NORTHWEST FLOW...OTHERWISE CLEARING CONDITIONS ACROSS THE FORECAST AREA SATURDAY NIGHT AND SUNDAY. AREAS OF FOG CAN BE EXPECTED AGAIN SUNDAY MORNING...BUT SHOULD NOT BE AS WIDESPREAD. HIGH TEMPERATURES WILL INCREASE A FEW DEGREES ON SUNDAY BUT REMAIN BELOW NORMAL. MONDAY...HIGH PRESSURE GETS PUSHED EAST IN RESPONSE TO THE NEXT UPSTREAM SYSTEM. DECENT ISENTROPIC LIFT WILL MOVE ACROSS THE CASCADES MONDAY AFTERNOON AND BUMPED UP POPS FOR ZONE 42 ACCORDINGLY. THE REMAINDER OF THE FORECAST AREA WILL REMAIN DRY WITH TEMPERATURES CLIMBING TO NEAR OR SLIGHTLY ABOVE SEASONAL NORMALS. /TOBIN MONDAY NIGHT THROUGH FRIDAY...MODELS IN GOOD AGREEMENT THROUGH THE EXTENDED PERIOD. A COLD FRONT QUICKLY MOVES ACROSS THE INLAND NORTHWEST OVERNIGHT MONDAY AND INTO TUESDAY MORNING FOR A SHOT OF MAINLY MOUNTAIN SHOWERS. A SHORTWAVE RIDGE QUICKLY BUILDS IN TUESDAY AFTERNOON FOR DRYING CONDITIONS. CLOUDS WILL DISSIPATE OVERNIGHT FOR A CHILLY MORNING WEDNESDAY. WEDNESDAY ONWARD A BROAD TROUGH DEVELOPS IN THE GULF OF ALASKA PUTTING EASTERN WA AND NORTH ID IN A WEST TO SOUTHWEST FLOW. LOOKS LIKE MOST OF THE ENERGY ASSOCIATED WITH THIS FEATURE GETS SHUNTED TO THE NORTH...HOWEVER CANNOT RULE OUT SOME ISOLATED MOUNTAIN SHOWERS ACROSS EXTREME NORTHERN WA AND NORTH ID THROUGH FRIDAY. /KOCH && .PRELIMINARY POINT TEMPS/POPS... SPOKANE 38 57 35 59 36 64 / 10 10 10 0 0 0 COEUR D'ALENE 35 56 35 58 35 62 / 10 30 10 0 0 0 PULLMAN 36 57 36 60 37 64 / 20 40 10 0 0 0 LEWISTON 40 60 39 63 40 69 / 20 40 20 0 0 0 COLVILLE 33 55 34 59 35 64 / 20 10 10 0 0 0 SANDPOINT 34 53 33 55 33 62 / 20 20 10 0 0 0 KELLOGG 35 52 36 57 37 62 / 20 50 10 0 0 0 MOSES LAKE 38 61 37 64 38 68 / 10 10 10 0 0 0 WENATCHEE 40 63 40 65 41 67 / 10 10 10 0 0 0 OMAK 37 61 35 63 36 68 / 10 10 10 0 0 10 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...NONE. WA...NONE. && $$ wa AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GREEN BAY WI 915 PM CDT FRI OCT 7 2005 .DISCUSSION...SCT LAKE-EFFECT PCPN EXPECTED TO CONT TNGT. BOTH THE NAM AND RUC SHOWED CONVERGENCE BAND DEVELOPING NR THE WRN SHORE OF THE LAKE OVERNIGHT...AND THEN MOVING INLAND. THAT FIT WELL WITH THE TREND ON STLT IMAGERY WHICH SHOWED CLDS INCRG OVER THE LAKE. WOULD EXPECT CLDS AND SCT PCPN TO CONT OVER E-C WI OVERNIGHT. ACRS THE REST OF THE FCST AREA...IT NOW APPEARS THAT CLOUDS WL NOT DISSIPATE AS CLEANLY AS PREV EXPECTED. THE AIR IS STILL COOL ENOUGH TO ALLOW TEMPS TO REACH THE MINS IN THE GOING FCST AS LONG AS THERE WL BE AT LEAST A PERIOD OF CLR SKIES. THAT WL PROBABLY HAPPEN IN MOST AREAS. ALREADY UPDATED EARLIER IN THE EVENING TO ADD THE LAKE-EFFECT IN E-C WI. WL UPDATE FCST PKG AGAIN TO INCR POPS FURTHER NR THE LAKE. UPDATED FCST SUITE WL BE OUT ASAP. && .GRB WATCHES/WARNINGS/ADVISORIES... FROST ADVISORY IN EFFECT FROM 1 AM TO 9 AM CDT SATURDAY WIZ013-020-021-030-031-035>037-045- && $$ SKOWRONSKI WEATHER.GOV/GREENBAY wi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LINCOLN IL 345 AM CDT SAT OCT 8 2005 .DISCUSSION... THE LATEST SURFACE ANALYSIS CONTINUED TO INDICATE A SURFACE RIDGE WEST OF THE STATE...WITH A NORTHERLY FLOW ACROSS ALL OF CENT AND SE IL. THE 3.9IR SATELLITE LOOP SHOWED A STRATOCU DECK PERSISTENT ALONG AND WEST OF THE IL RIVER VALLEY...WITH ANOTHER BAND COMING DOWN LAKE MICHIGAN INTO NORTHEAST PARTS OF THE FORECAST AREA AROUND DANVILLE. THE MAIN CHALLENGES IN THE NEAR TERM WILL BE WITH SKY COVER AND TEMPS THE NEXT COUPLE OF DAYS. THE MET AND MAV NUMERICAL GUIDANCE IS NOT HANDLING THE CLOUD COVER WELL AT ALL...ALTHOUGH THE NAM SOUNDINGS AND LOW LEVEL MOISTURE FIELDS OFFER BETTER CLUES. THE NEXT ISSUE WILL BE MID-WEEK WITH THE TIMING OF AN APPROACHING UPPER SYSTEM AND ITS ASSOCIATED PRECIP CHANCES SHORT TERM...TODAY THROUGH TUESDAY... WILL START OUT THE DAY MOSTLY CLOUDY IN WEST CENTRAL IL BASED ON CURRENT SATELLITE TRENDS. THE 00Z NAM AND 06Z RUC 800-900 MB RH FIELD WERE FAIRLY CLOSE IN DEPICTING THIS CLOUD COVER...AND INDICATE IT SHOULD STAY INTACT MUCH OF THE MORNING BEFORE SLOWLY DISSIPATING. THE REST OF CENTRAL AND SE IL WILL START OUT THE DAY MOSTLY SUNNY... WITH A GRADUAL INCREASE IN CLOUDS. THE EXCEPTION WILL BE IN AFOREMENTIONED AREAS OF ECENT IL FROM CMI-DNV WHERE LAKE EFFECT CLOUDS WILL MEANDER IN AND OUT THROUGHOUT THE DAY. THE AFFECT ON TEMPS WILL BE TO HAVE VALUES CLOSE TO OR SLIGHTLY WARMER THAN YESTERDAY IN THE 57 TO 62 RANGE. THE NEXT CLOUD COVER PROBLEM IS TONIGHT INTO SUNDAY. A NORTHEAST TO EAST WIND AND SHALLOW LOW LEVEL MOISTURE TRAPPED BELOW AN INVERSION SHOULD RESULT IN AN INCREASE IN CLOUD COVER OVERNIGHT AND INTO SUNDAY. REMANANTS OF AN UPPER LOW LIFTING INTO THE OHIO VALLEY FROM NRN TX ON SUNDAY WILL ALSO AID IN INCREASING CLOUD COVER...ESPECIALLY IN THE SOUTHERN HALF OF THE FORECAST AREA. LOWS WERE ADJUSTED UP SLIGHTLY AND HIGHS ON SUNDAY ADJUSTED DOWN A BIT TO ACCOUNT FOR THIS. A LIGHT NORTH TO NORTHEAST LOW LEVEL WIND FLOW IS ANTICIPATED MONDAY AND TUESDAY...BUT THE AIRMASS SHOULD MODERATE QUITE A BIT...GIVING US HIGHS NEAR 70 AND LOWS NEAR 50 WITH A PARTLY CLOUDY SKY. LONG TERM...WEDNESDAY THROUGH FRIDAY... BY MIDWEEK...THE GFS IS INDICATING THAT A CLOSED LOW FROM THE DESERT SOUTHWEST WILL OPEN UP AND LIFT TOWARD THE MIDWEST. THE ECMWF AND UKMET ARE SHOWING SIMILAR SOLUTIONS...BUT NOT AS QUICK AS THE GFS. NONE OF THE MODELS USUALLY DO A VERY GOOD JOB WITH CLOSED LOWS IN THE SOUTHWESTERN U.S....AND THEY ALMOST ALWAYS BRING THEM OUT TOO QUICKLY. THE LATEST GFSLR IS EVEN HINTING THAT THE PRECIP MAY HOLD OFF IN CENT/SE IL UNTIL LATER WED OR EVEN ON THURSDAY. DUE TO THE UNCERTAINTIES INVOLVED WILL LEAVE THE LOW CHANCES FOR SHOWERS IN THE FORECAST FOR WEDNESDAY...AND AVOID POSSIBLE FORECAST FLIP-FLOPS BY TAKING IT OUT AND PUSHING IT BACK TO THURSDAY. REGARDLESS...NO BIG PLUNGE OF COLD AIR OR RETURN TO ABNORMALLY WARM CONDITIONS IS ANTICIPATED LATE NEXT WEEK...SO WILL KEEP TEMPS IN LINE WITH SEASONAL NORMALS. && .ILX WATCHES/WARNINGS/ADVISORIES... IL...NONE. $$ MILLER il AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 619 AM EDT SAT OCT 8 2005 .UPDATE... WILL ISSUED A QUICK UPDATE TO REMOVE ALL MENTION OF SUNSHINE TODAY IN THE FAR SOUTHERN COUNTIES. THE BREAKS IN THE OVERCAST AROUND MONROE COUNTY HAVE COMPLETELY FILLED IN. BASED ON THE STRENGTH OF THE INVERSION... THESE CLOUDS SHOULD HANG AROUND FOR MUCH OF THE DAY. && .SHORT TERM...TODAY AND TONIGHT THE UPPER AIR PATTERN WILL BECOME MORE AMPLIFIED ACROSS NORTH AMERICA THROUGH THE SHORT TERM AS A STRONG UPPER JET NOSING INTO THE WEST COAST CARVES OUT DEEP TROUGH OVER THE WESTERN US BY SUN MORNING. MEANWHILE... A MID LEVEL CIRCULATION OVER THE SOUTHERN GREAT LAKES WILL SLOWLY MOVE INTO EASTERN OHIO TONIGHT...ALLOWING A MID LEVEL RIDGE TO BUILD ACROSS LOWER MICHIGAN TONIGHT. AN UPPER LOW OVER THE SOUTHEASTERN US WILL LIFT NORTH ALONG THE COAST. THE WATER VAPOR SHOWS A NICE PLUME OF TROPICAL MOISTURE STREAMING INTO THE MID ATLANTIC AND NORTHEAST US. THIS MOISTURE AND LIFT FROM THE SOUTHEASTERN WAVE WILL REMAIN EAST OF THE FORECAST AREA. WITH PERSISTENT NORTHEASTERLY FLOW ACROSS SE MICHIGAN TODAY... STRATUS WILL REMAIN THE MAIN FORECAST CONCERN THROUGH THE SHORT TERM. THE 00Z DTX SOUNDING SHOWED A STRONG INVERSION BASED NEAR 5K FEET. STRONG LOW LEVEL INSTABILITY OVER LAKE HURON HAS ALLOWED QUITE A BIT OF MOISTURE TO BECOME TRAPPED UNDERNEATH THIS INVERSION... RESULTING IN WIDESPREAD STRATUS ACROSS SOUTHEAST MICHIGAN. NORTHEASTERLY FLOW WILL PERSIST ACROSS LAKE HURON AND SOUTHEAST MICHIGAN TODAY. OF THE 00Z MODEL SUITE...THE RUC WAS THE ONLY SOLUTION TO HAVE A REASONABLE HANDLE ON THE STRENGTH AND DEPTH OF THE INVERSION. THE RUC HOWEVER SEEMS TO DRY OUT THE LOW LEVELS TOO QUICKLY. GIVEN THERE WILL BE SOME WEAK WARM AIR ADVECTION NEAR 850MB TODAY AND PERSISTENT NORTHEAST FLOW AND INSTABILITY OFF LAKE HURON... THINK THESE CLOUDS ARE GOING TO TAKE QUITE A WHILE TO DISSIPATE. THERE HAS BEEN SOME BREAKS IN THE CLOUDS OVERNIGHT ACROSS MONROE COUNTY. WITH THE ONSET OF DAYTIME HEATING... THIS MAY ALLOW SOME OF THE CLOUDS TO ERODE ACROSS THE SOUTH. NORTH-NORTHEASTERLY FLOW WILL ALSO ADD SOME DOWNSLOPE INTO WAYNE COUNTY. SO WILL CONTINUE TO HAVE THE CLOUDS BREAK UP A BIT ACROSS THE SOUTH. AS FOR THE REST OF THE FORECAST AREA... WILL KEEP SKIES MOSTLY CLOUDY THROUGH THE DAY. WILL THUS SIDE ON THE LOW END OF GUIDANCE MAX TEMPS...KEEPING MOST LOCALS IN THE 50S. THE LOW LEVEL FLOW WILL BECOME MORE EASTERLY TONIGHT...WHICH SHOULD FOCUS THE BEST POTENTIAL FOR LAKE EFFECT CLOUDS NORTH OF THE FORECAST AREA. MID LEVEL SUBSIDENCE WILL ALSO STRENGTHEN ACROSS LAKE HURON. SOME WARM AIR ADVECTION NEAR 925MB COUPLED WITH THE MID LEVEL SUBSIDENCE SHOULD WEAKEN THE INVERSION TONIGHT. MUCH DRYER LOW LEVEL AIR WILL ALSO ADVECT ACROSS LAKE HURON AND SHOULD EVENTUALLY WORK ITS WAY INTO SE MICHIGAN. SO WILL CONTINUE TO FORECAST A CLEARING TREND TONIGHT. DESPITE THE CLEARING... ENOUGH OF A GRADIENT SHOULD BE IN PLACE ACROSS SE MICHIGAN TO KEEP TEMPS FROM DROPPING TO NEAR FREEZING. GUIDANCE MIN TEMPS OF UPPER 30S TO LOWER 40S THUS LOOK REASONABLE. && .LONG TERM... LATEST WATER VAPOR IMAGERY INDICATING A CLOSED CIRCULATION OVER NORTH CENTRAL TEXAS. THIS FEATURE IS CURRENTLY EMBEDDED WITHIN A DRY AIRMASS AND IS ESSENTIALLY INACTIVE AT THE MOMENT. THIS SHOULD CHANGE AS THE SYSTEM INTERACTS WITH THE LEFTOVER MOISTURE ALONG THE EAST COAST EARLY NEXT WEEK. THE UPPER LOW WILL HEAD INTO LOWER MISSISSIPPI VALLEY BY SUNDAY...GRADUALLY LIFTING NORTH/NORTHEAST AS A MUCH STRONGER UPPER LOW MOVES INTO THE SOUTHERN ROCKIES. THE KEY TO THE FORECAST IS DETERMINING HOW MUCH MOISTURE WILL ADVECT IN FROM THE EAST...AS 500 MB LOW APPROACHES FROM THE SOUTH ON MONDAY. MODEL CONSENSUS (GFS/UKMET/CANADIAN/NOGAPS) FORECASTING THE SYSTEM TO TRACK INTO THE EASTERN GREAT LAKES MONDAY NIGHT/TUESDAY. THIS IS IS PRETTY MUCH WHAT YESTERDAY'S WRFXX RUN HAD. ALTHOUGH...TONIGHT'S WRFXX RUN STALLS THE UPPER LOW OVER OHIO. MAJORITY OF MODELS ARE SIGNIFICANTLY FATHER EAST THAN THE CURRENT 00Z NAM FORECASTED POSITION OVER CHICAGO. WITH THE EASTERN TRACK FAVORED...TOUGH CALL WHETHER OR NOT PRECIPITATION WILL WRAP BACK THIS FAR WEST (ESPECIALLY WITH MODELS TRENDING FATHER EAST). NONE-THE-LESS...STILL WORTHY OF LOW CHANCE POPS CHANCE POPS ACROSS THE EASTERN HALF OF THE CWA (MONDAY THROUGH TUESDAY)...PER CURRENT FORECAST. JUST MADE SOME MINOR TWEAKS TO TEMPERATURES TO LOWER THE DIURNAL RANGE BASED ON THE CONSIDERABLE CLOUD COVER EXPECTED. SHORTWAVE RIDGING OVER THE CENTRAL GREAT LAKES TUESDAY NIGHT/WEDNESDAY MORNING LOOKS TO BE BE SHORT LIVED AS THE MORE SIGNIFICANT UPPER LOW MOVES INTO THE UPPER MISSISSIPPI VALLEY ON WEDNESDAY (PER EUROPEAN/GFS/CANADIAN). OF COURSE...THIS IS NOT A DONE DEAL JUST YET....AS IT IS NOT OUT OF THE REALM OF POSSIBILITY THE NORTHERN STREAM SHORTWAVE TROUGH BYPASSES THE SYSTEM...WITH MUCH OF THE ENERGY LINGERING BACK ACROSS THE CENTRAL/SOUTHERN PLAINS. WITH THIS UNCERTAINTY...TIMING REMAINS PROBLEMATIC...BUT IT DOES LOOK LIKE WEDNESDAY WILL REMAIN DRY...AS MOISTURE IS NOT EXPECTED TO INCREASE IN EARNEST UNTIL VERY LATE IN THE DAY OR WEDNESDAY NIGHT. && .AVIATION... STRATUS WILL BE SLOW TO ERODE OVERNIGHT...AND WILL KEEP CEILINGS IN THE 2500-3500 FOOT AREA...SCATTERING OUT GRADUALLY IN THE 09Z TO 13Z TIMEFRAME. BY AND LARGE...EXPECT SCATTERED CLOUDS DURING THE DAY ON SATURDAY AS DRIER AIR WORKS INTO LOWER MICHIGAN. WINDS WILL HOLD FROM THE NORTHEAST...AND EXPECT GUSTS TO PUSH 20 KNOTS AGAIN MIDDAY. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...SMALL CRAFT ADVISORY...NEARSHORE WATERS FROM PORT AUSTIN TO PORT HURON INCLUDING SAGINAW BAY UNTIL 6 AM SUNDAY. LAKE ST CLAIR...SMALL CRAFT ADVISORY...UNTIL 6 PM SATURDAY. MI WATERS OF LAKE ERIE...SMALL CRAFT ADVISORY...UNTIL 6 AM SUNDAY. && $$ SHORT TERM...CONSIDINE LONG TERM...SF AVIATION...DG mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 339 AM EDT SAT OCT 8 2005 .SHORT TERM...TODAY AND TONIGHT THE UPPER AIR PATTERN WILL BECOME MORE AMPLIFIED ACROSS NORTH AMERICA THROUGH THE SHORT TERM AS A STRONG UPPER JET NOSING INTO THE WEST COAST CARVES OUT DEEP TROUGH OVER THE WESTERN US BY SUN MORNING. MEANWHILE... A MID LEVEL CIRCULATION OVER THE SOUTHERN GREAT LAKES WILL SLOWLY MOVE INTO EASTERN OHIO TONIGHT...ALLOWING A MID LEVEL RIDGE TO BUILD ACROSS LOWER MICHIGAN TONIGHT. AN UPPER LOW OVER THE SOUTHEASTERN US WILL LIFT NORTH ALONG THE COAST. THE WATER VAPOR SHOWS A NICE PLUME OF TROPICAL MOISTURE STREAMING INTO THE MID ATLANTIC AND NORTHEAST US. THIS MOISTURE AND LIFT FROM THE SOUTHEASTERN WAVE WILL REMAIN EAST OF THE FORECAST AREA. WITH PERSISTENT NORTHEASTERLY FLOW ACROSS SE MICHIGAN TODAY... STRATUS WILL REMAIN THE MAIN FORECAST CONCERN THROUGH THE SHORT TERM. THE 00Z DTX SOUNDING SHOWED A STRONG INVERSION BASED NEAR 5K FEET. STRONG LOW LEVEL INSTABILITY OVER LAKE HURON HAS ALLOWED QUITE A BIT OF MOISTURE TO BECOME TRAPPED UNDERNEATH THIS INVERSION... RESULTING IN WIDESPREAD STRATUS ACROSS SOUTHEAST MICHIGAN. NORTHEASTERLY FLOW WILL PERSIST ACROSS LAKE HURON AND SOUTHEAST MICHIGAN TODAY. OF THE 00Z MODEL SUITE...THE RUC WAS THE ONLY SOLUTION TO HAVE A REASONABLE HANDLE ON THE STRENGTH AND DEPTH OF THE INVERSION. THE RUC HOWEVER SEEMS TO DRY OUT THE LOW LEVELS TOO QUICKLY. GIVEN THERE WILL BE SOME WEAK WARM AIR ADVECTION NEAR 850MB TODAY AND PERSISTENT NORTHEAST FLOW AND INSTABILITY OFF LAKE HURON... THINK THESE CLOUDS ARE GOING TO TAKE QUITE A WHILE TO DISSIPATE. THERE HAS BEEN SOME BREAKS IN THE CLOUDS OVERNIGHT ACROSS MONROE COUNTY. WITH THE ONSET OF DAYTIME HEATING... THIS MAY ALLOW SOME OF THE CLOUDS TO ERODE ACROSS THE SOUTH. NORTH-NORTHEASTERLY FLOW WILL ALSO ADD SOME DOWNSLOPE INTO WAYNE COUNTY. SO WILL CONTINUE TO HAVE THE CLOUDS BREAK UP A BIT ACROSS THE SOUTH. AS FOR THE REST OF THE FORECAST AREA... WILL KEEP SKIES MOSTLY CLOUDY THROUGH THE DAY. WILL THUS SIDE ON THE LOW END OF GUIDANCE MAX TEMPS...KEEPING MOST LOCALS IN THE 50S. THE LOW LEVEL FLOW WILL BECOME MORE EASTERLY TONIGHT...WHICH SHOULD FOCUS THE BEST POTENTIAL FOR LAKE EFFECT CLOUDS NORTH OF THE FORECAST AREA. MID LEVEL SUBSIDENCE WILL ALSO STRENGTHEN ACROSS LAKE HURON. SOME WARM AIR ADVECTION NEAR 925MB COUPLED WITH THE MID LEVEL SUBSIDENCE SHOULD WEAKEN THE INVERSION TONIGHT. MUCH DRYER LOW LEVEL AIR WILL ALSO ADVECT ACROSS LAKE HURON AND SHOULD EVENTUALLY WORK ITS WAY INTO SE MICHIGAN. SO WILL CONTINUE TO FORECAST A CLEARING TREND TONIGHT. DESPITE THE CLEARING... ENOUGH OF A GRADIENT SHOULD BE IN PLACE ACROSS SE MICHIGAN TO KEEP TEMPS FROM DROPPING TO NEAR FREEZING. GUIDANCE MIN TEMPS OF UPPER 30S TO LOWER 40S THUS LOOK REASONABLE. && .LONG TERM... LATEST WATER VAPOR IMAGERY INDICATING A CLOSED CIRCULATION OVER NORTH CENTRAL TEXAS. THIS FEATURE IS CURRENTLY EMBEDDED WITHIN A DRY AIRMASS AND IS ESSENTIALLY INACTIVE AT THE MOMENT. THIS SHOULD CHANGE AS THE SYSTEM INTERACTS WITH THE LEFTOVER MOISTURE ALONG THE EAST COAST EARLY NEXT WEEK. THE UPPER LOW WILL HEAD INTO LOWER MISSISSIPPI VALLEY BY SUNDAY...GRADUALLY LIFTING NORTH/NORTHEAST AS A MUCH STRONGER UPPER LOW MOVES INTO THE SOUTHERN ROCKIES. THE KEY TO THE FORECAST IS DETERMINING HOW MUCH MOISTURE WILL ADVECT IN FROM THE EAST...AS 500 MB LOW APPROACHES FROM THE SOUTH ON MONDAY. MODEL CONSENSUS (GFS/UKMET/CANADIAN/NOGAPS) FORECASTING THE SYSTEM TO TRACK INTO THE EASTERN GREAT LAKES MONDAY NIGHT/TUESDAY. THIS IS IS PRETTY MUCH WHAT YESTERDAY'S WRFXX RUN HAD. ALTHOUGH...TONIGHT'S WRFXX RUN STALLS THE UPPER LOW OVER OHIO. MAJORITY OF MODELS ARE SIGNIFICANTLY FATHER EAST THAN THE CURRENT 00Z NAM FORECASTED POSITION OVER CHICAGO. WITH THE EASTERN TRACK FAVORED...TOUGH CALL WHETHER OR NOT PRECIPITATION WILL WRAP BACK THIS FAR WEST (ESPECIALLY WITH MODELS TRENDING FATHER EAST). NONE-THE-LESS...STILL WORTHY OF LOW CHANCE POPS CHANCE POPS ACROSS THE EASTERN HALF OF THE CWA (MONDAY THROUGH TUESDAY)...PER CURRENT FORECAST. JUST MADE SOME MINOR TWEAKS TO TEMPERATURES TO LOWER THE DIURNAL RANGE BASED ON THE CONSIDERABLE CLOUD COVER EXPECTED. SHORTWAVE RIDGING OVER THE CENTRAL GREAT LAKES TUESDAY NIGHT/WEDNESDAY MORNING LOOKS TO BE BE SHORT LIVED AS THE MORE SIGNIFICANT UPPER LOW MOVES INTO THE UPPER MISSISSIPPI VALLEY ON WEDNESDAY (PER EUROPEAN/GFS/CANADIAN). OF COURSE...THIS IS NOT A DONE DEAL JUST YET....AS IT IS NOT OUT OF THE REALM OF POSSIBILITY THE NORTHERN STREAM SHORTWAVE TROUGH BYPASSES THE SYSTEM...WITH MUCH OF THE ENERGY LINGERING BACK ACROSS THE CENTRAL/SOUTHERN PLAINS. WITH THIS UNCERTAINTY...TIMING REMAINS PROBLEMATIC...BUT IT DOES LOOK LIKE WEDNESDAY WILL REMAIN DRY...AS MOISTURE IS NOT EXPECTED TO INCREASE IN EARNEST UNTIL VERY LATE IN THE DAY OR WEDNESDAY NIGHT. && .AVIATION... STRATUS WILL BE SLOW TO ERODE OVERNIGHT...AND WILL KEEP CEILINGS IN THE 2500-3500 FOOT AREA...SCATTERING OUT GRADUALLY IN THE 09Z TO 13Z TIMEFRAME. BY AND LARGE...EXPECT SCATTERED CLOUDS DURING THE DAY ON SATURDAY AS DRIER AIR WORKS INTO LOWER MICHIGAN. WINDS WILL HOLD FROM THE NORTHEAST...AND EXPECT GUSTS TO PUSH 20 KNOTS AGAIN MIDDAY. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...SMALL CRAFT ADVISORY...NEARSHORE WATERS FROM PORT AUSTIN TO PORT HURON INCLUDING SAGINAW BAY UNTIL 6 AM SUNDAY. LAKE ST CLAIR...SMALL CRAFT ADVISORY...UNTIL 6 PM SATURDAY. MI WATERS OF LAKE ERIE...SMALL CRAFT ADVISORY...UNTIL 6 AM SUNDAY. && $$ SHORT TERM...CONSIDINE LONG TERM...SF AVIATION...DG mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 235 AM EDT SAT OCT 8 2005 .DISCUSSION... 00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW WSW FLOW ALF STRETCHING FM THE PAC NW INTO SE CAN. SHRTWV RDG PRESENT FM THE UPR MS VALLEY INTO ONTARIO...AND 1030MB SFC HI PRES NOTED JUST W OF JAMES BAY. DESPITE PRESENCE OF SFC HI AND VERY DRY AIR ALF SHOWN ON THE LOCAL RAOBS...QUITE A BIT OF SC LINGERING IN MOIST MIXED LYR UNDER SHARP INVRNS AT 00Z BTWN H9 AT APX/INL TO H825 AT GRB. SC MOST EXTENSIVE OVER THE CTNRL FA IN LLVL NE FLOW SHOWN ON THE MQT VWP AND STILL EVEN A FEW --SHRA...BUT CLR-PCLDY SKIES APRNT OVER THE FAR W AND OVER MOST OF THE E WHERE LLVL FLOW IS DOWNSLOPING. TEMPS AT 03Z HAVE FALLEN TO ARND 35 WHERE SKIES HAVE CLRD...BUT READINGS HOLDING UP MORE IN THE UPR 30S WHERE CLD HAS BEEN MORE PERSISTENT. OTRW...A SHRTWV RIDING ENEWD THRU SCNTRL CAN...BUT AREA OF HIER CLD ON ITS SRN FLANK IS ONLY BRUSHING NRN MN/FAR NW LK SUP AND APPEARS ON TRACK TO STAY NW OF THE FA. MAIN FCST CONCERNS TDAY ARE CLD TRENDS/TEMPS...THEN FOCUS INTO EARLY WEEK GENERALLY ON TEMPS WITH RDG FCST TO DOMINATE. H925 FLOW FCST TO VEER FM NE TO MORE E OVERNGT...AND VWP/WINDS AT THE LK SUP BUOYS SHOW A SLOW TREND IN THIS DIRECTION. DISTRIBUTION OF PRES RISE/FALL COUPLET ALSO WOULD SUG A VEERING LLVL FLOW. THIS WSHFT SHOULD PROMOTE CLRG OVER ALL BUT THE NCNTRL-KEWEENAW AND SRN MNM COUNTY. WL LOOK AT STLT TO DETERMINE COVG OF LO CLD NR FCST ISSUANCE AND PAINT GRIDS APPROPRIATELY. THEN FOR TDAY...SFC HI PRES RDG AXIS/ SHARP ACYC FLOW FCST TO PERSIST UNDER BLDG UPR HGTS. WITH H925 FLOW GRDLY TURNING MORE ESE DURING THE DAY UNDER INCRSG INSOLATION/SLOWLY SINKING SUBSIDENCE INVRN...SC SHOULD GRDLY MIX OUT...LATEST OVER THE KEWEENAW. OTRW...SHRTWV OVER SCNTRL CAN WL TRACK MORE NE...SO ASSOCIATED CLD SHOULD REMAIN TO THE NW IN GOOD AGREEMENT WITH STLT TRENDS. GFS/NAM FCST SDNGS SUG HI TEMPS WL REACH 50 TO 55 AT MOST SPOTS...IN GOOD AGREEMENT WITH MOS/GOING FCST. TNGT WL BE QUIET BUT ON THE CHILLY SIDE WITH SFC RDG AXIS REMAINING DOMINANT UNDER UPR RDG/PWAT ARND 0.35 INCH. A BIT CONCERNED NAM MOS HINTS AT DVLPMNT OF SOME LO CLD OVER MUCH OF THE CNTRL FA WHERE FCST LGT ESE WIND WOULD UPSLOPE MSTR OVER LK MI (WHERE THERE IS PLENTY OF LK CLD NOW) UNDER LO SUBSIDENCE INVRN IN THE PRESENCE OF DIURNAL COOLING. GFS FCST SDNGS ARE QUITE A BIT DRIER THAN THE NAM'S...SO NOT YET READY TO GO WITH EXTENSIVE LO CLD DVLPMNT EVEN THOUGH COVG OF LO CLD TNGT IN THE AREA WARRANTS CONCERNS. WL ADD PTCHY FOG/ST WITH IDEAL RADIATIONAL COOLING CONDITIONS ALLOWING TEMP TO FALL THRU CROSS OVER DWPTS NOT FAR FM 30 EXPECTED THIS AFTN. WL GO BLO MOS GUIDANCE FOR MIN TEMPS AND MAINTAIN GOING NUMBERS. EXCEPT FOR FEW-SCT CU ON SUN...ANOTHER PLEASANT EARLY FALL DAY APPEARS IN ORDER UNDER DOMINATING RDG FOLLOWING DISSIPATION OF ANY MRNG FOG/ST. WL HEDGE TOWARD HIER MAX TEMPS SHOWN BY THE GFS/NGM MOS PER MIXING TO INVRN BASE ARND H9 ON THE GFS FCST SDNGS. GOING FCST NEEDS LTL CHG. QUIET WX WL LINGER SUN NGT...BUT BOTH NAM/GFS SHOW A BIT SHARPER NE GRADIENT FLOW DVLPG OVERNGT IN RESPONSE TO RISING MSLP IN ONTARIO UNDER SHARPENING RDG DOWNSTREAM OF DEEPENING WRN TROF. A BIT TIGHTER GRADIENT FLOW WL LIMIT DIURNAL TEMP FALL AND FOG FORMATION AS TEMP WL HAVE A HARDER TIME FALLING THRU CROSS OVER DEWPT FCST SUN AFTN. BUT WL STILL GO A BIT LOWER THAN MOS GUIDANCE FOR LO TEMPS AND MAKE FEW CHGS TO GOING FCST WITH PWAT REMAINING LO UNDER RDG. MODELS REMAIN IN GOOD AGREEMENT SHOWING UPR LO/DEEPER MSTR DRAWN N BY INCRS SSW FLOW ALF DOWNSTREAM OF DEEPENING TROF OVER THE ROCKIES WL REMAIN WELL SE OF THE FA ON MON. SO ANOTHER MOSUNNY DAY ON TAP WITH NE FLOW ON THE SRN FLANK OF BLDG HI PRES ACRS ONTARIO. SINCE NE FLOW WL DRAW DOWN SOMEWHAT COOLER AIR (GFS/UKMET FCST H85 TEMPS 1-2C LOWER THAN ON SUN)...HAVE ADJUSTED GOING HI TEMPS DOWN A FEW DEGREES TO BE MORE IN LINE WITH MIXING TO INVRN BASE ON GFS FCST SDNGS. GOING DRY FCST INTO WED LOOKS ON TRACK. ALTHOUGH UPR HGTS FCST TO GRDLY FALL ON TUE...LTL IN THE WAY OF ISENTROPIC LIFT TO SATURATE THE LO LVLS OF ANTECEDENT AIRMASS. SO EVEN THOUGH THERE MAY AN INCRS IN HI CLD...NO PCPN EXPECTED. GOING FCST TEMPS FOR TUE APPEAR RSNBL AND MATCH SURROUNDING OFFICES...SO NO CHGS ATTM. && .MQT...WATCHES/WARNINGS/ADVISORIES... FREEZE WARNING UNTIL MID MRNG MIZ002>007-009>014-084-085. && $$ KC mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 100 AM EDT SAT OCT 8 2005 .AVIATION... STRATUS WILL BE SLOW TO ERODE OVERNIGHT...AND WILL KEEP CEILINGS IN THE 2500-3500 FOOT AREA...SCATTERING OUT GRADUALLY IN THE 09Z TO 13Z TIMEFRAME. BY AND LARGE...EXPECT SCATTERED CLOUDS DURING THE DAY ON SATURDAY AS DRIER AIR WORKS INTO LOWER MICHIGAN. WINDS WILL HOLD FROM THE NORTHEAST...AND EXPECT GUSTS TO PUSH 20 KNOTS AGAIN MIDDAY. && .SHORT TERM...TONIGHT AND SATURDAY...ISSUED AT 335 PM EDT A BLOCKY AND MESSY UPPER PATTERN ACROSS NOAM WITH TROPICAL REMNANTS PLAGUING THE EASTERN SEABOARD AND PACIFIC JET INFLUX ENTERING THE PACIFIC NORTHWEST. A NOTABLE SHORT WAVE, WITH NOT MUCH MOISTURE AND NO RADAR RETURNS, WAS SLOWLY PROGRESSING ACROSS ILLINOIS AND WITH THE ASSISTANCE OF 100+ 300MB JET ENTRANCE REGION OVERHEAD PROVIDING ENOUGH LIFT FOR CLOUD DEVELOPMENT. ON THE MESOSCALE...BANDS OF STRATUS UNDER THE AC/CS CONTINUE TO COME IN OFF OF LAKE HURON YET NO REPORTS OF PRECIP FROM SURROUNDING RADAR SITES AND OBSERVATIONS. COOL NORTHEAST GRADIENT FLOW WILL DOMINATE THROUGH THE SHORT TERM PERIOD. FOR TONIGHT...BOTH THE NAM AND GFS AGREE WITH SYNOPTIC SCALE SETTING UP OVERNIGHT AS SURFACE HIGH SLIDES ACROSS THE NORTHERN LAKES AND WAVES OF LOW PRESSURE TRACK UP THE EASTERN STATE. THIS WILL PROLONG THE EASTERLY FETCH OFF THE WARM WATERS OF LAKE HURON WITH INVERSION HEIGHTS SLOWLY FALLING THRU THE NIGHT. YET MODELS TEND TO CRASH THESE HEIGHTS TOO SOON AND LOOKING CLOSER AT THE RUC13 AND OTHER EXPERIMENTAL RUNS OF THE RUC/WRF...CONVERGENCE INCREASES OVERNIGHT OVER LAKE HURON INTO SAGINAW BAY WITH EVEN SOME HINT OF LIGHT QPF DEVELOPING INTO THE TRI CITIES REGION AND PORTIONS OF THE THUMB. THIS MIGHT BE THE RESULT OF A MORE CLEARING TREND UPSTREAM AND LAND BREEZE DEVELOPMENT TO ENHANCE CONVERGENCE FIELDS SOMEWHAT. THEREFORE, WE WILL INTRODUCE A CHANCE FOR SOME SPRINKLES FOR THOSE COUNTIES NORTH OF I69 AND EAST OF I75. OTHERWISE, WITH IMPRESSIVE INVERSION SETTING UP OVERNIGHT, LAKE STRATUS WILL LIKELY HOLD ON THROUGH MOST OF THE NIGHT. WITH AFOREMENTIONED SHORT WAVE APPROACHING...MODELS ARE CONSISTENT WITH Q-VECTOR CONVERGENCE THIS EVENING BUT LIMITED MOISTURE ALOFT SHOULD PROHIBIT ANY MENTION OF PRECIP. HEADING INTO SATURDAY ALL AVAILABLE GUIDANCE SUGGESTS THIS SHORT WAVE BECOMES STRUNG OUT AND WEAKENS EITHER OVER OR JUST SOUTHEAST OF THE STATE. EITHER WAY, THIS SHOULD INCREASE SUBSIDENCE FURTHER AND DRIER AIR UPSTREAM WILL BEGIN TO INFILTRATE NORTHERN LAKE HURON AND ASSIST WITH THE BREAK UP OF LAKE STRATUS CLOUDS. SO WE MIGHT START OFF WITH MORE CLOUDS BUT TRANSITION TOWARD MORE SUNSHINE THROUGH THE DAY...PTSUNNY FORECAST! MET NUMBERS LOOK TOO LOW AND LIKELY DUE TO MODELS' HIGH LOW LEVEL MOISTURE CONTENT AND CLOUD COVER. WE WILL SHADE CLOSER TO THE MAV/FWC NUMBERS. && .LONG TERM...SATURDAY NIGHT THROUGH FRIDAY...ISSUED AT 335 PM EDT SATURDAY NIGHT THROUGH SUNDAY NIGHT... SURFACE RIDGE OVER WESTERN GREAT LAKES REGION PRETTY MUCH HELD AT BAY THROUGH THE WEEKEND AS TROUGHING KEEPS REAFFIRMING ITSELF IN THE EAST. AT 500 MB...EARLIER WEAKENED SHORTWAVE TROUGH STILL WOBBLING AROUND VICINITY OF SOUTHEAST MI SATURDAY NIGHT AND SUNDAY. STILL CALLING FOR A RATHER TRANQUIL FORECAST FOR THIS TIME FRAME...WITH LITTLE OR NO SYNOPTIC SCALE LIFT. 850 TO 500 MB RELATIVE HUMIDITY RATHER DRY THROUGH SUNDAY...THEN INCREASING MOISTURE WORKING BACK IN SUNDAY NIGHT. 925 MB MOISTURE...IN MOIST NORTHEAST FLOW...A LITTLE BETTER...THOUGH EVEN THIS INCREASES SUNDAY NIGHT. GIVEN EXPECTED DEGREE OF CLOUDINESS ON BACK SIDE OF TROUGHING IN THE EAST...AND WIND FLOW OFF OF LAKE HURON...IT WILL DIFFICULT TO GENERATE ANY WIDESPREAD CLEARING OR FROST THIS WEEKEND. MONDAY THROUGH FRIDAY... 12Z RUNS CONTINUE TO DEPICT CONSENSUS OF 500 MB SHORTWAVE TROUGHING LIFTING NORTHEAST OUT OF THE LOWER MS VALLEY INTO SOUTHERN LAKES REGION BY MONDAY AHEAD OF CLOSED SOUTHWESTERN USA LOW...FOLLOWED BY SHORTWAVE RIDGING WHICH SHOULD SET UP AHEAD OF WESTERN LOW/TROUGH COMPLEX AT LEAST BY WEDNESDAY...A LITTLE EARLIER VIA 00Z/12Z WRFXX...06Z DGEX...00Z GLOBAL. THEN...THE WESTERN SYSTEM MOVES IN AFTER MID WEEK TO BRING UNSETTLEDNESS/MOISTURE TO FORECAST AREA. AT THE SURFACE...INVERTED TROUGHINESS CONTINUING TO PUNCH NORTHWARD INTO EASTERN LAKES REGION AND INTO BROAD RIDGE TO THE NORTH EARLY IN WEEK. SOME SORT OF TROUGH OR FRONT MOVING IN FOR LATTER PART OF WEEK AS PER MODEL CONSENSUS. BY MONDAY...GOOD MODEL CONSENSUS SHOWING RELATIVELY DEEP MOISTURE IN PLACE...WEAK LOW TO MID LEVEL OMEGA LIFT...WEAK 850 TO 700 MB THETA E RIDGE BULGING INTO AT LEAST EASTERN COUNTIES FROM THE EAST/SOUTHEAST... MODEST SURFACE CONVERGENCE WITH A LITTLE UPPER LEVEL DIVERGENCE TO BOOT...AND WEAK 305K ISENTROPIC ASCENT WITH LOWERING CONDENSATION PRESSURE DEFICITS. WILL INTRODUCE CHANCE SHOWERS FOR MONDAY THROUGH TUESDAY TIME FRAME EASTERN COUNTIES OF FORECAST AREA...AND MAY HAVE TO LATER EXPAND WEST IF LATER MODEL RUNS CONFIRM RECENT TRENDS. AS BEFORE...CHANCE POPS WEDNESDAY NIGHT AND THURSDAY...WHICH WILL BE CONTINUED THROUGH FRIDAY. GUIDANCE TEMPERATURES APPEAR TO BE IN THE BALL PARK. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...SMALL CRAFT ADVISORY...NEARSHORE WATERS FROM PORT AUSTIN TO PORT HURON AND ALSO FOR SAGINAW BAY...UNTIL 6 AM SUNDAY. LAKE ST CLAIR...SMALL CRAFT ADVISORY...LCZ460...UNTIL 6 AM SATURDAY. MI WATERS OF LAKE ERIE...SMALL CRAFT ADVISORY...LEZ444...UNTIL 6 AM SUNDAY. && $$ SHORT TERM...BGM LONG TERM....DWD AVIATION.....DG mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE ST LOUIS MO 340 AM CDT SAT OCT 8 2005 .DISCUSSION... MDLS RMN IN GENL AGREEMENT WITH SYNOPTIC TRENDS OVR REGION. UPR RDG FCST TO BUILD INTO UPR MSVLY AND UPR GTLKS...WHILE CUTOFF LOW OVR N TX DRIFTS NE INTO OHIO VLY. THIS WL KP STG SFC RDG THAT RUNS FROM THE GTLKS TO S PLAINS QSTNRY DURING THE WEEKEND. THIS PTRN SHUD LEND ITSELF TO COOLER THAN NORMAL TEMPS AND LTL IN THE WAY OF PCPN. THE EXACT TEMP TRENDS WL RELY HEAVILY ON SKY COVER. PINNING DOWN THESE SPECIFICS IS PROVING TO BE SMWHAT DFCLT AS CAN BE SEEN BY THE CHAOTIC CLD TRENDS DEPICTED BY THE STLT PICS OVRNGT. WHILE THERE MAY BE SM EXPANSION OF THE LOW CLOUDS OVR THE NXT FEW HRS...NAM...GFS...AND RUC SOUNDINGS DON'T LOCK A SGFNT AMT OF MSTR BLO INVERSION TDA...SO THINK THAT ONCE THE SUN BGNS WORKING ON THE ERY MRNG CLDS THEY SHUD SCT OUT...AND LACK OF CYC CRCLN SHUD KP ANY DIURNAL DVLPMT FROM BCMG A SGFNT CLD DECK. SAT NGT CULD BE A REPEAT OF TNGT...WITH PATCHES OF SC FLOATING ACR AREA. GOING TEMPS TDA AND TNGT LK GOOD WITH ONLY A FEW TWEEKS. ADDL CLDNS SHUD MV INTO AREA ON SUN AS MID CLDS ACCOMPANY THE NE MVMT OF THE UPR LO. THE NAM WANTS TO ADD TO THE CLD CVR BY ONCE AGAIN SUGGESTING A THICK ST/SC LYR FORMING IN MOIST E LO LVL FLOW. THIS LWR CLD DECK SEEMS TO BE A MAJOR REASON FOR THE FOR THE DIFFERENCE IN MAX TEMPS BTWN MAV/MET MOS AT SM STATIONS FOR SUN. SINCE THE NAM APPEARED TO BE A BIT TOO ROBUST WITH THE LO LVL RH IN YSTDAS 00Z RUN WONT TOTALLY BUY INTO THIS MUCH LO CLDNS. HWVR...DUE TO THE RTVLY COOL SFC RDG EVEN THE THICKENING MID CLDS MAY TRY TO CUT INTO TEMPS...SO HV MADE A SLGT DOWNWARD ADJ TO SUN TEMPS...MNLY IN S AREAS. INCRG PCPN CHCS BY MIDWK STLL LK GD AS UPR LO SPINS INTO PLAINS...SO NO CHGS RQRD TO MEDIUM RANGE. && .LSX WATCHES/WARNINGS/ADVISORIES... MO...NONE. IL...NONE. && $$ TRUETT mo AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON NC 123 AM EDT SAT OCT 8 2005 .MARINE UPDATE... WIDESPREAD 35-40 KT WIND GUSTS ARE OCCURRING AS JUST OBSERVED AT THE SEVERAL BEACHFRONT STATIONS AND BUOY 41013. SINCE THE WINDS DO NOT APPEAR TO BE CONFINED TO DISTINCT CONVECTIVE ELEMENTS...WILL UPGRADE TO A SHORT-FUSE GALE WARNING FOR THE WATERS NORTH OF LITTLE RIVER INLET THROUGH 10Z...6 AM EDT. THE LOW LEVEL JET CREATING THESE WINDS SHOULD PULL NORTH OF THE WATERS BY THIS TIME WITH WINDS SUBSIDING SUBSTANTIALLY BY LATER IN THE MORNING. UPDATE: TRA && .SHORT TERM (OVERNIGHT/FLOOD POTENTIAL)... NO ZONE UPDATE IS PLANNED AT THIS TIME. THERE HAS BEEN A WELCOME RELATIVE LULL IN THE RAINFALL ACROSS THE AREA OVER THE LAST FEW HOURS. IT DOES APPEAR THOUGH THAT ONE MORE ROUND OF HEAVY RAIN IS IN STORE FOR THE REGION DURING THE OVERNIGHT HOURS. A LOW TO MID LEVEL JET IS ROUNDING THE EAST SIDE OF THE LOW OVER THE FL PANHANDLE. LARGE SCALE ASCENT ASSOC WITH THIS FEATURE IS CAUSING CONVECTION TO BLOSSOM EAST OF FLORIDA. SAT IMAGERY SHOWS THAT IT WILL BE HEADED RIGHT FOR THE CAPE FEAR REGION. GFS HAS BEEN DOING QUITE WELL WITH THE MOISTURE AND TAKEN LITERALLY IT WOULD SUGGEST THAT THE VERY BEST CHANCE FOR HEAVY RAIN WILL BE CONFINED TO COASTAL COUNTIES...PERHAPS THE NC COASTAL COUNTIES MORESO THAN THE SC COUNTIES. FLOOD WATCH WILL STAY AS IS THOUGH SINCE THE GROUND IS SO SATURATED THAT EVEN A LITTLE RAINFALL INLAND COULD LEAD TO MORE FLOODING ISSUES. LOW LEVEL FLOW SHOULD BE BACKED ENOUGH TO THE SOUTH TO CHANNEL THE DEEP MOISTURE TO THE EAST BY DAYBREAK SATURDAY. HOPEFULLY THE FLOOD WATCH WILL NOT NEED TO BE EXTENDED BEYOND ITS EXPIRATION TIME (ONCE AGAIN...MAYBE IN THE NC COASTAL COUNTIES). && .AVIATION... HAVE LARGELY CARRIED ON TRENDS FROM TODAY IN AT LEAST THE COASTAL TERMINALS AS SHOWERS CONTINUE TO STREAM ONSHORE IN A DEEP AND JUICY SSE FEED. TOO DIFFICULT TO TIME THE INDIVIDUAL POCKETS OF PRECIP...AND EXPECT ADDITIONAL DEVELOPMENT OFFSHORE OVERNIGHT...SO I WENT WITH TEMPO GROUPS TO GO BETWEEN MVFR/VFR CIGS IN THE BREAKS...TO BORDERLINE MVFR/IFR CIG AND VIS IN THE PRECIP. SERIOUS DIPS INTO IFR WILL BE TOO BRIEF TO EVEN WARRANT A TEMPO. WILL MAINTAIN MVFR CIGS THRU THE LATTER HALF OF THE TAFS...WITH KFLO EVEN IMPROVING TO VFR IN THE AFTERNOON AS THE AXIS OF DEEPEST MOISTURE FINALLY SHIFTS EAST OF THE AREA. && .MARINE... WAVES OF SHOWERS CONTINUE TO ROLL NORTH ACROSS THE COASTAL WATERS THIS EVENING. SUSTAINED WINDS OUTSIDE SHOWERS ARE GENERALLY 15-20 KT...BUT DOWNDRAFTS IN THE CONVECTION ARE LIKELY PRODUCING GUSTS UPWARD OF 30 KNOTS AT TIMES...AS WELL AS LOCALLY HIGHER SEAS. THE NAM AND RUC MODELS BOTH INDICATE A LOW LEVEL JET ORGANIZING ACROSS THE COASTAL WATERS SOUTH AND EAST OF CAPE FEAR AROUND MIDNIGHT TONIGHT...THEN SLOWLY LIFTING NORTH ALONG ONSLOW BAY EARLY SATURDAY MORNING. THERE WILL LIKELY BE AN ENHANCEMENT OF CONVECTIVE ACTIVITY IN THIS JET...WHICH WILL LEAD TO AN INCREASE IN SURFACE WIND SPEEDS AND GUSTS AFTER MIDNIGHT. GUSTS COULD EXCEED 35 KNOTS WHICH MAY LEAD TO SPECIAL MARINE WARNINGS LATER TONIGHT. IT IS DEFINITELY NOT A NIGHT TO PLAN AN EXCURSION OFFSHORE. BUOY 41013 MAY HAVE SUSTAINED DAMAGE TO ITS WAVE SENSOR AS IT HAS ONLY REPORTED SEA HEIGHT ONE HOUR OUT OF THE PAST 24. LATEST WAVEWATCH FORECASTS AND DATA FROM BUOY 41004 (EAST OF CHS) INDICATE LITTLE CHANGE IS NEEDED TO OUR SEAS FORECAST TONIGHT...6 TO 9 FEET OFF SC AND 8 TO 11 FEET OFF NC - HIGHEST IN THE VICINITY OF FRYING PAN SHOALS. && .ILM WATCHES/WARNINGS/ADVISORIES... NC...FLOOD WATCH FOR ALL NC COUNTIES UNTIL 6 AM SATURDAY. SC...FLOOD WATCH FOR ALL SC COUNTIES EXCEPT DARLINGTON AND MARLBORO UNTIL 6 AM SATURDAY. MARINE...GALE WARNING SURF CITY TO LITTLE RIVER INLET THROUGH 6 AM SATURDAY. ...SMALL CRAFT ADVISORY LITTLE RIVER INLET TO S SANTEE RIVER THROUGH SATURDAY EVENING. ...SMALL CRAFT ADVISORY SURF CITY TO LITTLE RIVER INLET FROM 6 AM SATURDAY THROUGH EARLY SUNDAY MORNING. $$ SHORT TERM...MBB AVIATION...RAS MARINE...TRA nc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MIDLAND/ODESSA TX 421 AM CDT SAT OCT 8 2005 .SHORT TERM... 11-3.9 SATELLITE CONTINUE TO SHOW LOW CLOUDS ENTRENCHED OVER THE SOUTHERN DAVIS MOUNTAINS...MARFA PLATEAU AND BIG BEND REGION. THE LOWER LEVELS WILL REMAIN MOIST THROUGH THE MORNING HOURS AND LOW CLOUDS/FOG WILL CONTINUE TO DEVELOP OVER PORTIONS OF WEST TEXAS AND SOUTHEASTERN NEW MEXICO. FAVORED LOCATIONS FOR DEVELOPMENT ACCORDING TO THE LATEST SATELLITE LOOP AND RUC40 DATA WILL BE OVER SOUTHEASTERN NEW MEXICO...THE PECOS RIVER VALLEY AND THE STOCKTON PLATEAU. WE HAVE UPDATED THE FORECAST TO INCREASE CLOUD COVER OVER THE ABOVE MENTIONED REGIONS AS WELL AS ADD MORNING FOG TO MOST OTHER AREAS. MORNING LOW CLOUDS AND FOG ARE EXPECTED TO GIVE WAY TO MOSTLY SUNNY SKIES OVER THE AREA AS A MID-LEVEL TROUGH MOVES INTO THE WESTERN U.S. SURFACE PRESSURE FALLS IN ADVANCE OF THIS TROUGH WILL ALLOW A LEE SIDE TROUGH TO DEVELOP OVER THE PLAINS OF EASTERN NEW MEXICO. THIS WILL ALLOW RETURN SOUTH TO SOUTHWESTERLY FLOW TO SETUP OVER THE AREA BY MIDDAY. 850MB THERMAL RIDGE WILL STRENGTHEN AND THUS TEMPERATURES TODAY WILL WARM CONSIDERABLY OVER THE PREVIOUS DAY/S BELOW NORMAL TEMPERATURES. GIVEN THE STRENGTH OF THE 850MB THERMAL RIDGE... WE HAVE RAISED TEMPERATURES A CATEGORY OR TWO FOR MOST LOCATIONS TODAY. SOUTH TO SOUTHWESTERLY LOW-LEVEL FLOW WILL CONTINUE TONIGHT AS SHORT RANGE MODELS SUGGEST A WEAK MESO-LOW WILL DEVELOP OVER THE UPPER TRANS PECOS REGION. TONIGHT/S LOW TEMPERATURES WILL BE CLOSER TO NORMAL GIVEN SLOWLY INCREASING DEW POINTS AND SURFACE WINDS. FOR NOW...WE ARE NOT EXPECTING LOW CLOUD DEVELOPMENT TONIGHT... BUT FOG MAY DEVELOP OVER THE DAVIS MOUNTAINS AND MARFA PLATEAU REGION WHERE WINDS ARE EXPECTED TO BE LIGHT AFTER MIDNIGHT. WE WILL NOT INCLUDE THE MENTION OF FOG FOR THE REMAINDER OF THE REGION AS WINDS ARE EXPECTED TO REMAIN IN THE 5 TO 10 MPH RANGE...WHICH WILL HAMPER FOG FORMATION. .LONG TERM... THE MAIN WEATHER SYSTEM THIS FORECAST CYCLE IS THE TROUGH THAT IS CURRENTLY MOVING ONTO THE WEST COAST AND IS STILL FORECAST TO SLOWLY MOVE EAST THROUGH THE MUCH OF THE FORECAST CYCLE. THE BEST CHANCE OF SHOWERS AND THUNDERSTORMS STILL APPEARS TO SUNDAY NIGHT AS A POTENT UPPER LOW DIGS INTO THE FOUR CORNER AREA WITH A PACIFIC FRONT SLATED TO MOVE EAST ACROSS THE REGION WITH GOOD UPPER FORCING SUNDAY NIGHT. INCREASED POPS 10 PERCENT ACROSS THE NORTHERN HALF OF THE REGION FURTHER INTO THE CHANCE CATEGORY. THE UPPER LOW WILL THEN TRANSLATE NORTHEAST SLOWLY THROUGH THE SOUTHERN ROCKIES INTO THE WESTERN HIGH PLAINS MONDAY AND TUESDAY. STRONG WESTERLY FLOW ALOFT WILL PUSH THE BEST MOISTURE AND INSTABILITY TOWARDS THE EASTERN PERMIAN BASIN BOTH DAYS WHERE THE PACIFIC FRONT WILL SLOW MONDAY AND THE ARRIVAL OF A NORTHERN STREAM COOL FRONT TUESDAY. WOULD BE TEMPTING TO PULL POPS ACROSS THE EASTERN PERMIAN BASIN WITH THE STRONGER WESTERLY FLOW ALOFT BUT MOISTURE AND INSTABILITY TYPICALLY GETS HUNG UP ACROSS THE LOWER TRANS PECOS AND THE SOUTHEAST PERMIAN BASIN DUE TO TERRAIN AND LIGHTER MID LEVEL WINDS. SOME WRAPAROUND SHOWERS ARE POSSIBLE ACROSS THE NORTH MONDAY DUE TO THE PROXIMITY OF THE UPPER LOW BEFORE IT TRACKS FURTHER NORTH...DID NOT MENTION IN WEATHER GRID YET BUT WILL NEED TO BE MONITORED. BEYOND TUESDAY MUCH OF THE ENERGY FROM THE UPPER LOW WILL HAVE PASSED TO THE NORTH AND EAST. THE SOUTHERN PORTION OF THE LOW WILL LAG AS A TROUGH ACROSS THE SOUTHWEST UNITED STATES. WENT WITH ISOLATED TO WIDELY SCATTERED SHOWERS AND THUNDERSTORMS THURSDAY WITH TROUGH IN PLACE ACROSS THE DESERT SOUTHWEST. THE BEST CHANCE SHOULD BE WESTERN SECTIONS CLOSEST TO THE DISTURBANCE. LEFT FRIDAY DRY FOR NOW BUT WITH UPPER TROUGH AXIS PROBABLY SOMEWHERE IN THE VICINITY POPS MAY EVENTUALLY BE NEEDED. TWEAKED HIGH TEMPERATURES SEVERAL DAYS IN THE EXTENDED BASED ON PROGGED 850 MILLIBAR TEMPERATURES. TWEAKED LOW TEMPERATURES. POPULATED WIND GRIDS WITH THE MEXMAF. LOOKS LIKE WINDY CONDITIONS IN THE GUADALUPES SUNDAY AND COLUMBUS DAY. && .AVIATION... A BRIEF PERIOD OF MVFR VISIBILITIES WILL BE POSSIBLE AT AREA TAF SITES THIS MORNING AS TEMPERATURE AND DEW POINT SPREADS CONVERGE. BRIEF MVFR CIGS ARE ALSO EXPECTED AT KINK AND POSSIBLY KCNM. THE 10Z-15Z TIME FRAME WILL BE FAVORED FOR FOG AND LOW CLOUDS. DISSIPATION OF FOG AND LOW CLOUDS WILL BE QUICKER WITH MOST AREAS INTO VFR RANGE AROUND 16Z. STRATUS DECK OVER THE MARFA PLATEAU AND BIG BEND REGION MAY TAKE A LITTLE LONGER TO DISSIPATE AS THE MOISTURE IS A LITTLE DEEPER IN THIS REGION. && .PRELIMINARY POINT TEMPS/POPS... BIG SPRING TX 72 55 81 64 / 0 0 10 30 CARLSBAD NM 79 56 86 60 / 0 0 20 40 DRYDEN TX 75 56 86 64 / 0 0 0 20 FORT STOCKTON TX 76 58 86 64 / 0 0 10 20 GUADALUPE PASS TX 77 58 81 55 / 0 0 20 30 HOBBS NM 77 55 86 62 / 0 0 20 40 MARFA TX 75 48 83 55 / 0 0 20 20 MIDLAND INTL AIRPORT TX 74 55 82 63 / 0 0 10 40 ODESSA TX 74 56 83 63 / 0 0 10 40 WINK TX 80 56 88 65 / 0 0 20 40 && .MAF WATCHES/WARNINGS/ADVISORIES... NM...NONE. TX...NONE. && $$ 06/12/99 tx AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LINCOLN IL 1025 AM CDT SAT OCT 8 2005 .DISCUSSION... MORNING SURFACE ANALYSIS SHOWS RIDGE AXIS EDGING CLOSER TO ILLINOIS...NOW EXTENDING FROM THE UPPER GREAT LAKES INTO IOWA/NORTHERN MISSOURI. 12Z SOUNDINGS AT BOTH KILX AND KDVN CONTINUE TO INDICATE A SHALLOW MOIST LAYER NEAR 850MB TRAPPED BENEATH A STRONG INVERSION. RUC 850MB RH FORECASTS SHOW MOISTURE SPREADING FROM NORTHEAST TO SOUTHWEST ACROSS THE KILX CWA THIS MORNING...VERY SIMILAR TO LATEST VISIBLE SATELLITE LOOP. EARLY OCTOBER SUN WILL LIKELY MIX A GOOD DEAL OF THIS SHALLOW MOISTURE OUT LATER THIS AFTERNOON...SO THINK SKIES WILL NOT GO COMPLETELY OVERCAST. NAM CU-RULE BACKS THIS UP...INDICATING ONLY SCT CU. WILL UPDATE GRIDS FOR CURRENT SATELLITE TRENDS...WITH SKIES BECOMING PARTLY SUNNY ACROSS THE BOARD BY AFTERNOON. TEMP FORECAST IS RIGHT ON TRACK...SO NO ZONE UPDATE NEEDED AT THIS TIME. && .PREV DISCUSSION... THE LATEST SURFACE ANALYSIS CONTINUED TO INDICATE A SURFACE RIDGE WEST OF THE STATE...WITH A NORTHERLY FLOW ACROSS ALL OF CENT AND SE IL. THE 3.9IR SATELLITE LOOP SHOWED A STRATOCU DECK PERSISTENT ALONG AND WEST OF THE IL RIVER VALLEY...WITH ANOTHER BAND COMING DOWN LAKE MICHIGAN INTO NORTHEAST PARTS OF THE FORECAST AREA AROUND DANVILLE. THE MAIN CHALLENGES IN THE NEAR TERM WILL BE WITH SKY COVER AND TEMPS THE NEXT COUPLE OF DAYS. THE MET AND MAV NUMERICAL GUIDANCE IS NOT HANDLING THE CLOUD COVER WELL AT ALL...ALTHOUGH THE NAM SOUNDINGS AND LOW LEVEL MOISTURE FIELDS OFFER BETTER CLUES. THE NEXT ISSUE WILL BE MID-WEEK WITH THE TIMING OF AN APPROACHING UPPER SYSTEM AND ITS ASSOCIATED PRECIP CHANCES SHORT TERM...TODAY THROUGH TUESDAY... WILL START OUT THE DAY MOSTLY CLOUDY IN WEST CENTRAL IL BASED ON CURRENT SATELLITE TRENDS. THE 00Z NAM AND 06Z RUC 800-900 MB RH FIELD WERE FAIRLY CLOSE IN DEPICTING THIS CLOUD COVER...AND INDICATE IT SHOULD STAY INTACT MUCH OF THE MORNING BEFORE SLOWLY DISSIPATING. THE REST OF CENTRAL AND SE IL WILL START OUT THE DAY MOSTLY SUNNY... WITH A GRADUAL INCREASE IN CLOUDS. THE EXCEPTION WILL BE IN AFOREMENTIONED AREAS OF ECENT IL FROM CMI-DNV WHERE LAKE EFFECT CLOUDS WILL MEANDER IN AND OUT THROUGHOUT THE DAY. THE AFFECT ON TEMPS WILL BE TO HAVE VALUES CLOSE TO OR SLIGHTLY WARMER THAN YESTERDAY IN THE 57 TO 62 RANGE. THE NEXT CLOUD COVER PROBLEM IS TONIGHT INTO SUNDAY. A NORTHEAST TO EAST WIND AND SHALLOW LOW LEVEL MOISTURE TRAPPED BELOW AN INVERSION SHOULD RESULT IN AN INCREASE IN CLOUD COVER OVERNIGHT AND INTO SUNDAY. REMNANTS OF AN UPPER LOW LIFTING INTO THE OHIO VALLEY FROM NRN TX ON SUNDAY WILL ALSO AID IN INCREASING CLOUD COVER...ESPECIALLY IN THE SOUTHERN HALF OF THE FORECAST AREA. LOWS WERE ADJUSTED UP SLIGHTLY AND HIGHS ON SUNDAY ADJUSTED DOWN A BIT TO ACCOUNT FOR THIS. A LIGHT NORTH TO NORTHEAST LOW LEVEL WIND FLOW IS ANTICIPATED MONDAY AND TUESDAY...BUT THE AIRMASS SHOULD MODERATE QUITE A BIT...GIVING US HIGHS NEAR 70 AND LOWS NEAR 50 WITH A PARTLY CLOUDY SKY. LONG TERM...WEDNESDAY THROUGH FRIDAY... BY MIDWEEK...THE GFS IS INDICATING THAT A CLOSED LOW FROM THE DESERT SOUTHWEST WILL OPEN UP AND LIFT TOWARD THE MIDWEST. THE ECMWF AND UKMET ARE SHOWING SIMILAR SOLUTIONS...BUT NOT AS QUICK AS THE GFS. NONE OF THE MODELS USUALLY DO A VERY GOOD JOB WITH CLOSED LOWS IN THE SOUTHWESTERN U.S....AND THEY ALMOST ALWAYS BRING THEM OUT TOO QUICKLY. THE LATEST GFSLR IS EVEN HINTING THAT THE PRECIP MAY HOLD OFF IN CENT/SE IL UNTIL LATER WED OR EVEN ON THURSDAY. DUE TO THE UNCERTAINTIES INVOLVED WILL LEAVE THE LOW CHANCES FOR SHOWERS IN THE FORECAST FOR WEDNESDAY...AND AVOID POSSIBLE FORECAST FLIP-FLOPS BY TAKING IT OUT AND PUSHING IT BACK TO THURSDAY. REGARDLESS...NO BIG PLUNGE OF COLD AIR OR RETURN TO ABNORMALLY WARM CONDITIONS IS ANTICIPATED LATE NEXT WEEK...SO WILL KEEP TEMPS IN LINE WITH SEASONAL NORMALS. && .ILX WATCHES/WARNINGS/ADVISORIES... IL...NONE. $$ BARNES/MILLER il AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NORTHERN INDIANA 615 AM EST SAT OCT 8 2005 .AVIATION... LATEST SATELLITE LOOP AND SFC OBS CONTINUE TO SHOW EXTENSIVE 4KFT CLOUD DECK OVER THE AREA THIS MORNING. RUC SOUNDINGS SHOW THAT STRONG 850MB INVERSION WILL PERSIST THROUGH THE DAY. NOW APPEARS MOISTURE WILL REMAIN TRAPPED UNDER THIS INVERSION AND DO NOT EXPECT THIS TO MIX OUT SO WILL KEEP VFR CEILINGS IN AT BOTH TAF SITES THIS PERIOD. && .SHORT TERM... AN UPPER LEVEL TROUGH WILL BE LEAVING THE AREA THIS MORNING, WHILE THE SURFACE HIGH PRESSURE CONTINUES TO BUILD INTO THE REGION TODAY AND THEN REMAINS OVER THE AREA TONIGHT(THE VALUE OF THE ISOBARS OVER THE CWA WILL NOT CHANGE THAT MUCH TONIGHT). THE WIND TODAY AND TONIGHT WILL REMAIN OUT OF THE NORTHEAST WITH THE WIND WEAKENING SOME TONIGHT AS WE LOSE THE DAYTIME HEATING AND THE ISOBARS ARE NOT QUITE AS TIGHTLY PACKED TONIGHT AS THEY WILL BE TODAY. WITH THE AREA BEING IN THE SAME AIR MASS TODAY AS YESTERDAY...HIGHS TODAY WILL BE FAIRLY SIMILAR AND THE LOWS TONIGHT SHOULD BE COOLER WITH LESS CLOUD COVER EXPECTED TONIGHT THAN THERE WAS THIS PREVIOUS NIGHT. THE CLOUD COVER FOR TODAY IS THE BIGGEST QUESTION...WHICH COULD ALSO HAVE AN AFFECT ON THE TEMPS TODAY. WATCHING SATELLITE PICTURES YOU CAN SEE THE GREAT LAKES GENERATING OUR CLOUD COVER AND THE WIND DIRECTION AND SPEED IS NOT EXPECTED TO CHANGE MUCH FOR TODAY. SO SEAMS THAT THE CLOUDS SHOULD CONTINUE...HOWEVER...MODELS ARE ALSO SHOWING GOOD SUBSIDENCE TODAY WHICH SHOULD BE ON THE INCREASE AS THE HIGH WORKS ITS WAY INTO THE AREA TODAY...AND HOW MUCH IS THIS SUBSIDENCE GOING TO AFFECT THINGS. THAT UPPER LEVEL TROUGH WILL ALSO BE LEAVING THE AREA THIS MORNING...TAKING SOME OF THE HELP FOR KEEPING THE CLOUDS HERE...AWAY. TRIED TO GO MAINLY FOR MOSTLY CLOUDY SKIES THIS MORNING WITH THE CWA BECOMING PARTLY CLOUDY THIS AFTERNOON. THE NORTHERN PART OF OUR CWA SHOULD SEE MORE CLOUDS THIS AFTERNOON THAN OUR SOUTHERN PART AS THE CLOUDS BEGIN TO BREAK UP IN OUR SOUTHERN PART. && .LONG TERM... OVERALL PATTERN THIS PERIOD WOULD CONTINUE TO SUPPORT STAYING WITH DRY FORECAST THROUGH DAY 7. A COUPLE OF UPPER LEVEL DISTURBANCES STILL EXPECTED TO MOVE THROUGH THE REGION NEXT WEEK BUT RETURN FLOW FROM GULF STILL LOOKING TO REMAIN CUT OFF AND LITTLE MORE THAN INVERTED TROF SEEN IN SFC PATTERN WITH THESE SYSTEMS. SO WHILE IT IS CERTAINLY POSSIBLE THAT PRECIP WILL OCCUR AT SOME POINT NEXT WEEK...LOW CONFIDENCE IN ANY ONE PARTICULAR FEATURE WOULD SUGGEST AVOIDING POTENTIAL FOR FLIP-FLOP FORECAST AND STAY WITH PERSISTENCE FOR NOW. EXPECT GRADUAL MODERATION IN TEMPS THROUGH THE PERIOD GOING FROM A FEW DEGREES BELOW NORMAL ON SUNDAY TO A FEW ABOVE NORMAL BY MID-WEEK. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...SMALL CRAFT ADVISORY UNTIL 5 PM EST THIS AFTERNOON FOR LMZ043- LMZ046. && $$ SHORT TERM...98 LONG TERM....04 AVIATION...04 in AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE JACKSON KY 1027 AM EDT SAT OCT 8 2005 .DISCUSSION... LOW LEVEL NORTHEAST FLOW...WITH SATELLITE SHOWING LOW CLOUD SPREADING SOUTHWEST ACROSS WESTERN KY. BASED ON CURRENT TRENDS AND LATEST RUC AND 06Z NAM SHOWING LOW LEVEL MOISTURE REMAINING IN PLACE ACROSS EAST KY...HAVE INCREASED SKY COVER IN THE NEAR TERM GRIDS. WAS ALREADY OVERCAST TODAY IN THE GRIDS BUT HAVE INCREASED SKY COVER FOR TONIGHT AND SUNDAY AS WELL. TEMPERATURES LOOK ON TARGET FOR TODAY WITH CURRENT TEMPERATURES RUNNING CLOSE TO GRIDDED FORECAST. MOSTLY DRIZZLE TO FALL OUT OF SHALLOW CLOUD DECK TODAY...BUT HAVE LEFT IN LOW CHANCE POPS FOR MEASUREABLE LIGHT RAIN AS LOZ DID MEASURE ONE-HUNDREDTH OF AN INCH WITH -RA THIS MORNING. UPDATED PRODUCT FORECAST SUITE IN THE PROCESS OF BEING TRANSMITTED. && .PREV DISCUSSION... 520 AM EDT SAT OCT 8 2005 SFC CHART THIS MORNING SHOWING HIGH PRESSURE OVER THE GREAT LAKES...AND WAVY FRONTAL BOUNDARY LAYING ROUGHLY ALONG THE SPINE OF THE APPALACHIANS. SATELLITE SHOWING PLENTY OF CLOUD COVER ACROSS THE REGION AND WATER VAPOR IS SHOWING A FAIRLY POTENT SHORTWAVE MOVING SLOWLY THROUGH THE MIDWEST. RADAR AND SFC OBS INDICATE A SWATH OF LIGHT RAIN MOVING INTO THE UPPER OHIO VALLEY...WITH PATCHY DRIZZLE IN ITS WAKE AND LIGHT RAIN SHOWERS FURTHER WEST ASSOCIATED WITH SHORTWAVE. MODELS WERE IN DECENT AGREEMENT WITH TWO MAIN SHORT WAVES TO CONTEND WITH. THE FIRST MOVES THROUGH THE AREA TODAY. THE SECOND PUSHES ACROSS THE TN VALLEY AND INTO THE OHIO VALLEY LATE SUNDAY NIGHT AND MONDAY. BEST ESTIMATE WOULD PUT THE SHORTWAVE THROUGH EASTERN KENTUCKY BY EARLY MONDAY AFTERNOON. DECIDED TO INCREASE MONDAYS SLIGHT POPS TO LOW CHANCE WITH HIGHEST POPS SLATED FOR THE MID MORNING PERIOD. NOT REALLY EXPECTING MUCH IN THE WAY OF PRECIPITATION TODAY...BUT LEFT A SLIGHT POP IN THE FORECAST FOR THE AREA UNTIL THE SHORT WAVE COMPLETES ITS PUSH THROUGH THE REGION. AXIS OF UPPER AIR TROUGH WILL HAVE MADE IT THROUGH THE AREA BY THIS AFTERNOON...SO WENT WITH MAINLY MORNING TYPE WORDING FOR PRECIP IN THE ZONES. ALSO LEFT HIGHER POPS IN THE EAST WITH SHOWERS STILL SHOWING UP ON RADAR MOVING NORTHEAST FROM TN AND VA. VERY CURIOUS AT HOW MOS GUIDANCE WAS SO DIFFERENT...WITH OVERALL FEATURES IN THE MODEL RUNS BEING QUITE SIMILAR. THIS MADE FOR A DIFFICULT TEMP FORECAST. LOOKING OVER TIME HEIGHT SERIES AND FCST SOUNDINGS...EXPECT SUBSIDENCE BEHIND THE SHORTWAVE TO DRY OUT THE MID AND UPPER LEVELS OF THE ATMOSPHERE TODAY. HOWEVER...MODELS AGREE ON A VERY MOIST AND CLOUDY BOUNDARY LAYER. UPSLOPE FLOW WILL HELP TO GUARANTEE THIS FOR AT LEAST MOST OF THE DAY. BUT CAN NOT RULE OUT A PEAK AT THE SUN IN THE SOUTHWEST THIS AFTERNOON. CONSEQUENTLY WENT WITH COOLER AFTERNOON HIGHS THAN MAV MOS ADVERTISED...BUT WARMER THAN WHAT APPEARS TO BE THE MET MOS PRECIP COOLED TEMPS. LEANED TOWARDS WARMER OVERNIGHT LOWS TONIGHT AS CLOUD COVER SHOULD STILL BE SUBSTANTIAL. THEREAFTER...LEANED TOWARDS MAV MOS TEMPS AS IT HAS RECENTLY BEEN PERFORMING BETTER THAN THE MET AND FWC MOS. 955 PM EDT FRI OCT 7 2005 AREAS OF LIGHT RAIN CONTINUE TO PERSIST IN THE FAR EASTERN SECTIONS OF THE FORECAST AREA IN REGION OF MID LEVEL DEFORMATION ZONE...WHICH IS FORECAST TO SHIFT EAST OVERNIGHT. WHILE NO MEASURABLE PRECIPITATION IS FALLING ACROSS THE WESTERN 2/3RDS OF THE FORECAST AREA...ISENTROPIC LIFT ALONG 310K SFC IS FORECAST TO INCREASE AFTER 6Z AS UPPER LEVEL SHORTWAVE CURRENTLY ACROSS SE MICHIGAN AND ASSOCIATED UPPER TROF APPROACH. THEREFORE WILL KEEP POPS FOR THIS AREA...BUT WILL LOWER THEM. ALSO WILL KEEP MENTION OF DRIZZLE THROUGH THE OVERNIGHT HOURS. FOR CONTINUITY PURPOSES...LOWERED POPS SATURDAY AS WELL. OTHERWISE...NO MAJOR CHANGES WERE MADE TO TEMPS/WINDS/CLOUD COVER. 350 PM EDT FRI OCT 7 2005 .DISCUSSION...SHORT TERM (SAT-MON)...MAIN CHALLENGES FOR SHORT TERM ARE TEMPERATURES AND PRECIPITATION CHANCES ONCE AGAIN. WENT WITH A BLEND OF MAV AND FWC MOS TEMPERATURES FOR BOTH MIN AND MAX TEMPERATURES FOR THE WEEKEND...WITH A SLIGHTLY WARMER DAY SUNDAY AND MONDAY. FELT WITH THE CLOUD COVER IN PLACE...AND THE FACT THAT THIS CLOUD COVER WILL ALSO REMAIN IN PLACE...FELT MOS MIN TEMPERATURES FOR SATURDAY NIGHT WERE A BIT TO COOL...SO WENT A FEW DEGREES ABOVE MOS FOR WEEKEND LOWS. AS FOR RAIN CHANCES...A SHORT WAVE TROUGH CAN BE SEEN MOVING WESTWARD OUT OF THE CENTRAL PLAINS IN CURRENT WATER VAPOR IMAGERY. A STATIONARY FRONTAL BOUNDARY IS ALSO STILL DRAPED ACROSS EASTERN KENTUCKY. WATER VAPOR IMAGERY SHOWING A STEADY FLUX IN MOISTURE FROM THE SOUTH INTERACTING WITH AND MOVING OVER THE FRONT. WITH AMPLE MOISTURE IN PLACE IN LOW AND MIDLEVELS...STILL FEEL LIKE ENOUGH CONVERGENCE WILL OCCUR ALONG AND JUST BEHIND FRONT TO ALLOW FOR AN INCREASE IN COVERAGE OF RAIN SHOWERS AND DRIZZLE THIS EVENING AND TONIGHT...WITH PRECIPITATION TAPERING OFF DURING THE LATE MORNING HOURS ON SATURDAY. WITH LACK OF JET SUPPORT...NOT ANTICIPATING ANYMORE THAN LIGHT RAIN ACROSS THE FA. SUNDAY SHOULD BE MAINLY DRY...WITH A SLIGHT CHANCE OF RAIN LATE SUNDAY NIGHT...AND A CHANCE OF RAIN AGAIN ON MONDAY AS ANOTHER SHORTWAVE APPROACHES FROM THE WEST. DEWPOINTS WERE ONLY SLIGHTLY ADJUSTED...AND WINDS LOOKED GOOD AS WELL...SO NO MAJOR CHANGES WERE MADE. FOR THE PERIOD MONDAY THROUGH FRIDAY... THE LONGWAVE PATTERN THROUGH THE EXTENDED WILL PLACE KENTUCKY IN THE DOWNSTREAM EFFECTS OF A DEEP FOUR CORNERS LOW THAT OPENS UP BY MIDWEEK AND LIFTS INTO SOUTH CENTRAL CANADA. ENERGY LEFT BEHIND IN THE DEEP SOUTH...BY OUR CURRENT NEIGHBORHOOD TROUGH...WILL COME NORTHEAST THROUGH THE OHIO VALLEY ON MONDAY...LINGERING AS A WEAK CLOSED LOW THROUGH MIDWEEK. THIS WILL THEN OPEN UP IN TANDEM WITH THE FOUR CORNERS LOW LIFTING NORTH AS WELL. FOLLOWING THIS...WEAKER FLOW WILL REMAIN OVER THE OHIO VALLEY THROUGH THE END OF THE WORK WEEK BEFORE THE NEXT TROUGH CATCHES UP WITH LEFTOVER ENERGY FROM THE FOUR CORNERS LOW...AS IT APPROACHES THE UPPER MIDWEST. THIS RESULTS IN A DEEPENING TROUGH THAT COULD THREATEN THE AREA FOR NEXT WEEKEND. FOLLOWED A BLEND OF THE GFS AND ECMWF FOR THIS PART OF THE FORECAST. FOR THE MOST PART...SENSIBLE WEATHER IN THE EXTENDED...WILL FEATURE LINGERING LOW MOISTURE FROM THIS WEEKEND/S LOW AND SLOW MOVING FRONT. HIGH PRESSURE AT THE SFC WILL ATTEMPT TO CLEAR OUT THE MOISTURE...BUT WITH NO REAL PUSH FROM ALOFT THIS WILL BE A SLOW PROCESS....AT BEST. AS SUCH...HAVE INCREASED CLOUDS AND RAISED LOWS THROUGH THE PERIOD...BUT LEFT THE HIGHS NEAR NORMAL. THE PRECIPITATION CHANCES WILL MAINLY BE IN THE SLIGHT CHANCE TO NONE RANGE DUE TO THE WEAK SFC FEATURES...WITH A SLIGHT DIURNAL TREND MIXED IN. HAVE ALSO KEPT THE QPF POTENTIAL LOW FOR NEXT WEEK. && .JKL WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SBH ky AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 719 AM EDT SAT OCT 8 2005 .AVIATION... A 0930Z ACARS SOUNDING ON DECENT INTO DTW SHOWED A VERY STRONG INVERSION NEAR 4700FT. A COLD NORTHEASTERLY FLOW ACROSS THE GREAT LAKES HAS ALLOWED LAKE EFFECT STRATUS TO BECOME TRAPPED UNDERNEATH THIS INVERSION. THE LATEST SATELLITE AND 11Z SURFACE OBS INDICATE THESE CLOUDS EXTEND ACROSS MOST OF THE STATE. THE INVERSION SHOULD REMAIN QUITE STRONG THROUGHOUT THE DAY. WITH PERSISTENT NORTHEASTERLY FLOW... THESE CLOUDS WILL BE HARD PRESSED TO DISSIPATE. HIGH PRESSURE WILL SLOWLY BUILD ACROSS THE NORTHERN GREAT LAKES TODAY. THIS IS EXPECTED TO FILTER SOME DRYER LOW LEVEL AIR ACROSS SOUTHERN ONTARIO... WHICH SHOULD ALLOW THE LOW CLOUDS TO BREAK UP AROUND DTW/DET LATE THIS AFTERNOON OR EVENING. THE FLOW WILL BECOME A LITTLE MORE EASTERLY TONIGHT. THIS COUPLED WITH THE LOW LEVEL DRY AIR ADVECTION AND A WEAKENING INVERSION SHOULD ALLOW THE CLOUDS TO SCOUR OUT AROUND FNT AND MBS AFTER 00Z. THE BASES OF THE CLOUDS CURRENTLY RANGE FROM 2400 TO 3500 FT. DAYTIME HEATING MAY BE ABLE TO ALLOW THE CLOUD BASES TO RISE ABOVE 3K FT THIS AFTERNOON. && .UPDATE... WILL ISSUED A QUICK UPDATE TO REMOVE ALL MENTION OF SUNSHINE TODAY IN THE FAR SOUTHERN COUNTIES. THE BREAKS IN THE OVERCAST AROUND MONROE COUNTY HAVE COMPLETELY FILLED IN. BASED ON THE STRENGTH OF THE INVERSION... THESE CLOUDS SHOULD HANG AROUND FOR MUCH OF THE DAY. && .SHORT TERM...TODAY AND TONIGHT THE UPPER AIR PATTERN WILL BECOME MORE AMPLIFIED ACROSS NORTH AMERICA THROUGH THE SHORT TERM AS A STRONG UPPER JET NOSING INTO THE WEST COAST CARVES OUT DEEP TROUGH OVER THE WESTERN US BY SUN MORNING. MEANWHILE... A MID LEVEL CIRCULATION OVER THE SOUTHERN GREAT LAKES WILL SLOWLY MOVE INTO EASTERN OHIO TONIGHT...ALLOWING A MID LEVEL RIDGE TO BUILD ACROSS LOWER MICHIGAN TONIGHT. AN UPPER LOW OVER THE SOUTHEASTERN US WILL LIFT NORTH ALONG THE COAST. THE WATER VAPOR SHOWS A NICE PLUME OF TROPICAL MOISTURE STREAMING INTO THE MID ATLANTIC AND NORTHEAST US. THIS MOISTURE AND LIFT FROM THE SOUTHEASTERN WAVE WILL REMAIN EAST OF THE FORECAST AREA. WITH PERSISTENT NORTHEASTERLY FLOW ACROSS SE MICHIGAN TODAY... STRATUS WILL REMAIN THE MAIN FORECAST CONCERN THROUGH THE SHORT TERM. THE 00Z DTX SOUNDING SHOWED A STRONG INVERSION BASED NEAR 5K FEET. STRONG LOW LEVEL INSTABILITY OVER LAKE HURON HAS ALLOWED QUITE A BIT OF MOISTURE TO BECOME TRAPPED UNDERNEATH THIS INVERSION... RESULTING IN WIDESPREAD STRATUS ACROSS SOUTHEAST MICHIGAN. NORTHEASTERLY FLOW WILL PERSIST ACROSS LAKE HURON AND SOUTHEAST MICHIGAN TODAY. OF THE 00Z MODEL SUITE...THE RUC WAS THE ONLY SOLUTION TO HAVE A REASONABLE HANDLE ON THE STRENGTH AND DEPTH OF THE INVERSION. THE RUC HOWEVER SEEMS TO DRY OUT THE LOW LEVELS TOO QUICKLY. GIVEN THERE WILL BE SOME WEAK WARM AIR ADVECTION NEAR 850MB TODAY AND PERSISTENT NORTHEAST FLOW AND INSTABILITY OFF LAKE HURON... THINK THESE CLOUDS ARE GOING TO TAKE QUITE A WHILE TO DISSIPATE. THERE HAS BEEN SOME BREAKS IN THE CLOUDS OVERNIGHT ACROSS MONROE COUNTY. WITH THE ONSET OF DAYTIME HEATING... THIS MAY ALLOW SOME OF THE CLOUDS TO ERODE ACROSS THE SOUTH. NORTH-NORTHEASTERLY FLOW WILL ALSO ADD SOME DOWNSLOPE INTO WAYNE COUNTY. SO WILL CONTINUE TO HAVE THE CLOUDS BREAK UP A BIT ACROSS THE SOUTH. AS FOR THE REST OF THE FORECAST AREA... WILL KEEP SKIES MOSTLY CLOUDY THROUGH THE DAY. WILL THUS SIDE ON THE LOW END OF GUIDANCE MAX TEMPS...KEEPING MOST LOCALS IN THE 50S. THE LOW LEVEL FLOW WILL BECOME MORE EASTERLY TONIGHT...WHICH SHOULD FOCUS THE BEST POTENTIAL FOR LAKE EFFECT CLOUDS NORTH OF THE FORECAST AREA. MID LEVEL SUBSIDENCE WILL ALSO STRENGTHEN ACROSS LAKE HURON. SOME WARM AIR ADVECTION NEAR 925MB COUPLED WITH THE MID LEVEL SUBSIDENCE SHOULD WEAKEN THE INVERSION TONIGHT. MUCH DRYER LOW LEVEL AIR WILL ALSO ADVECT ACROSS LAKE HURON AND SHOULD EVENTUALLY WORK ITS WAY INTO SE MICHIGAN. SO WILL CONTINUE TO FORECAST A CLEARING TREND TONIGHT. DESPITE THE CLEARING... ENOUGH OF A GRADIENT SHOULD BE IN PLACE ACROSS SE MICHIGAN TO KEEP TEMPS FROM DROPPING TO NEAR FREEZING. GUIDANCE MIN TEMPS OF UPPER 30S TO LOWER 40S THUS LOOK REASONABLE. && .LONG TERM... LATEST WATER VAPOR IMAGERY INDICATING A CLOSED CIRCULATION OVER NORTH CENTRAL TEXAS. THIS FEATURE IS CURRENTLY EMBEDDED WITHIN A DRY AIRMASS AND IS ESSENTIALLY INACTIVE AT THE MOMENT. THIS SHOULD CHANGE AS THE SYSTEM INTERACTS WITH THE LEFTOVER MOISTURE ALONG THE EAST COAST EARLY NEXT WEEK. THE UPPER LOW WILL HEAD INTO LOWER MISSISSIPPI VALLEY BY SUNDAY...GRADUALLY LIFTING NORTH/NORTHEAST AS A MUCH STRONGER UPPER LOW MOVES INTO THE SOUTHERN ROCKIES. THE KEY TO THE FORECAST IS DETERMINING HOW MUCH MOISTURE WILL ADVECT IN FROM THE EAST...AS 500 MB LOW APPROACHES FROM THE SOUTH ON MONDAY. MODEL CONSENSUS (GFS/UKMET/CANADIAN/NOGAPS) FORECASTING THE SYSTEM TO TRACK INTO THE EASTERN GREAT LAKES MONDAY NIGHT/TUESDAY. THIS IS IS PRETTY MUCH WHAT YESTERDAY'S WRFXX RUN HAD. ALTHOUGH...TONIGHT'S WRFXX RUN STALLS THE UPPER LOW OVER OHIO. MAJORITY OF MODELS ARE SIGNIFICANTLY FATHER EAST THAN THE CURRENT 00Z NAM FORECASTED POSITION OVER CHICAGO. WITH THE EASTERN TRACK FAVORED...TOUGH CALL WHETHER OR NOT PRECIPITATION WILL WRAP BACK THIS FAR WEST (ESPECIALLY WITH MODELS TRENDING FATHER EAST). NONE-THE-LESS...STILL WORTHY OF LOW CHANCE POPS CHANCE POPS ACROSS THE EASTERN HALF OF THE CWA (MONDAY THROUGH TUESDAY)...PER CURRENT FORECAST. JUST MADE SOME MINOR TWEAKS TO TEMPERATURES TO LOWER THE DIURNAL RANGE BASED ON THE CONSIDERABLE CLOUD COVER EXPECTED. SHORTWAVE RIDGING OVER THE CENTRAL GREAT LAKES TUESDAY NIGHT/WEDNESDAY MORNING LOOKS TO BE BE SHORT LIVED AS THE MORE SIGNIFICANT UPPER LOW MOVES INTO THE UPPER MISSISSIPPI VALLEY ON WEDNESDAY (PER EUROPEAN/GFS/CANADIAN). OF COURSE...THIS IS NOT A DONE DEAL JUST YET....AS IT IS NOT OUT OF THE REALM OF POSSIBILITY THE NORTHERN STREAM SHORTWAVE TROUGH BYPASSES THE SYSTEM...WITH MUCH OF THE ENERGY LINGERING BACK ACROSS THE CENTRAL/SOUTHERN PLAINS. WITH THIS UNCERTAINTY...TIMING REMAINS PROBLEMATIC...BUT IT DOES LOOK LIKE WEDNESDAY WILL REMAIN DRY...AS MOISTURE IS NOT EXPECTED TO INCREASE IN EARNEST UNTIL VERY LATE IN THE DAY OR WEDNESDAY NIGHT. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...SMALL CRAFT ADVISORY...NEARSHORE WATERS FROM PORT AUSTIN TO PORT HURON INCLUDING SAGINAW BAY UNTIL 6 AM SUNDAY. LAKE ST CLAIR...SMALL CRAFT ADVISORY...UNTIL 6 PM SATURDAY. MI WATERS OF LAKE ERIE...SMALL CRAFT ADVISORY...UNTIL 6 AM SUNDAY. && $$ SHORT TERM/AVIATION...CONSIDINE LONG TERM...SF mi AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE RALEIGH NC 1115 AM EDT SAT OCT 8 2005 .SHORT TERM (THIS AFTERNOON)... DURING THE MORNING...ENHANCED RAINFALL...MAINLY JUST EAST OF THE RALEIGH COUNTY WARNING AREA...AIDED BY STRONG SURFACE CONVERGENCE AS NOTED ON MSAS ANALYSIS...AND STRONG UPPER DIVERGENCE AS OBSERVED ON THE 250MB UPPER-AIR ANALYSIS. GOOD COOLING OF CLOUD TOPS ON IR IMAGES OVER THE COASTAL PLAIN THIS MORNING SHOWING SOME WARMING AS THE AFTERNOON APPROACHED...IN ADVANCE OF MUCH DRIER MID-LEVEL AIR HEADED NORTHEAST INTO SOUTHERN NORTH CAROLINA AHEAD OF A WEAK UPPER LOW OVER FAR SOUTHERN SOUTH CAROLINA. COMMA HEAD MOISTURE AHEAD OF UPPER LOW WILL SLOWLY LIFT NORTHEAST DURING THE DAY. ANTICIPATE THE HEAVIEST RAIN TO REMAIN JUST EAST OF CENTRAL NORTH CAROLINA COUNTIES AND CONTINUE TO GRADUALLY SHIFT EAST AS UPPER DIVERGENCE WEAKENS THROUGH THE AFTERNOON ON THE RUC AND A 40-50KT 500MB JET...DEPICTED ON THE KMHX RAOB AND SHOWN WELL ON THE RUC...SHIFTS EAST AND NORTHEAST AS WELL. K INDICES AND 850MB THETA-E...DESPITE REMAINING HIGH...ARE FORECAST TO DIMINISH SOME THIS AFTERNOON IN EASTERN COUNTIES BELOW VALUES OF THE MORNING. FOR THE EARLY AFTERNOON...NUMEROUS SHOWERS...ALBEIT LIGHT...WEST THROUGH THE TRIANGLE AND THE TRIAD SHOULD ALSO BECOME MORE SCATTERED. MSAS ANALYSIS AND SURFACE OBSERVATIONS SHOW THE SURFACE FRONT TO BE LOCATED BASICALLY ACROSS BURLINGTON SOUTH THROUGH ROCKINGHAM. THE FRONT WILL BE VERY SLOW TO MOVE EAST THIS AFTERNOON. BY MID AFTERNOON THE RUC FORECAST LIFTED INDICES BELOW ZERO MAINLY FROM U.S. EASTWARD...AND THIS GENERALLY MAKES SENSE GIVEN THE HIGHER MOISTURE THAT WILL REMAIN IN THE EAST AND THE POTENTIAL FOR JUST A LITTLE MORE HEATING THAN ELSEWHERE ESPECIALLY TOWARD FAYETTEVILLE AND CLINTON...WHERE 850MB MOISTURE IS FORECAST TO DIMINISH SLIGHTLY EARLY THIS AFTERNOON. MODIFIED GSO SOUNDING FOR MID-TO-UPPER 70S AND SMALL CHANGES IN TEMPERATURE ALOFT SHOWS A CAPE NEAR 2000J/KG... IN LINE OR JUST SLIGHTLY ABOVE THE LATE AFTERNOON RUC FORECAST VALUES. HAVE INCLUDED ISOLATED THUNDER POSSIBLE IN EASTERN AND SOUTHEAST ZONES. ALTHOUGH LCL VALUES WILL REMAIN LOW...RUC MODEL SOUNDING HELICITY FORECASTS ARE NOT TERRIBLY IMPRESSIVE THIS AFTERNOON...BELOW 100M2/S2 THROUGHOUT CENTRAL NORTH CAROLINA. TWEAKED TEMPERATURES A TOUCH...MAINLY LOWER DUE TO EXPECTED CLOUD COVER...WHICH SHOULD HANG TOUGH FOR THE MOST PART THROUGHOUT THE AFTERNOON AS THE LOW-LEVEL RELATIVE HUMIDITY STAYS VERY HIGH. COULD NOT LOWER TOO MUCH...THOUGH...AS HIGH DEW POINTS KEPT TEMPERATURES FROM FALLING TOO MUCH LAST NIGHT. GRIDDED AND WORDED FORECASTS ALREADY ISSUED. && .PREVIOUS DISCUSSION... (ISSUED 210 AM EDT SAT OCT 8 2005) SYNOPSIS... WATER VAPOR IMAGERY DEPICTED THE MID AND UPPER LEVEL LOW TO BE LOCATED OVER EASTERN GA MOVING NE WITH NEGATIVELY TILTED SHORT WAVE ENHANCING RAINFALL OVER THE MTNS. IMPRESSIVE TROPICAL FEED OF MOISTURE CONTINUED TO FLOW FROM OFF THE ATLANTIC NNW ACROSS SC AND CENTRAL NC... AHEAD OF THE UPPER LOW. MID LEVEL DRYING EXTENDED FROM NE GA... SSE TO NEAR CHS. A SURFACE TROUGH EXTENDED FROM A WEAK LOW (1003 MB) NEAR AUGUSTA NORTH THROUGH THE WESTERN PIEDMONT OF NC. SHORT TERM (TODAY)... MOST OF THE WIDESPREAD SIGNIFICANT HEAVY RAIN HAS BEEN FALLING NEAR THE SURFACE AND H85 TROUGH LOCATED OVER THE FOOTHILLS OF NC AND VA DURING FRIDAY EVENING... AND ALONG THE SE COAST. LIGHTER RAINS CONTINUED ACROSS MUCH OF CENTRAL NC DURING THE PAST FEW HOURS... WITH SCATTERED HEAVY TROPICAL SHOWERS. RAINFALL AMOUNTS DURING THE PAST 3 HOURS HAVE AVERAGED AROUND A TENTH OF AN INCH WITH SCATTERED AREAS RECEIVING A QUARTER TO A HALF INCH. STORM TOTALS THUS FAR HAVE AVERAGED BETWEEN 1 AND 2.5 INCHES EXCEPT 2.5 TO 3.5 INCHES OVER PORTIONS OF THE S-W PIEDMONT AND OVER THE SANDHILLS AND COASTAL PLAIN. THE RAH 88D ESTIMATED PRECIPITATION ESTIMATES (IN TROPICAL ZR MOST OF THE EVENT)... HAVE BEEN ABOUT 50-60 PERCENT OF GROUND TRUTH REALITY. THE GROUND TRUTH AMOUNTS HAVE BEEN QUITE VARIABLE DUE TO THE TROPICAL CONVECTIVE NATURE OF THE RAINFALL. IT APPEARS THE GFS HAS HAD THE BEST HANDLE ON DEPICTING THE QPF MINIMUM OVER CENTRAL NC WITH THIS EVENT WITH MAXIMUMS ALONG THE BLUE RIDGE... AND ALONG THE SE COAST. FLASH FLOOD GUIDANCE REMAINS HIGH BUT HAS LOWERED QUITE A BIT IN THE PAST 24 HOURS... ESPECIALLY OVER THE HILLY TERRAIN OF FORSYTH COUNTY (WINSTON-SALEM) WHERE THEY WERE AT THE LOW END OF THE GUIDANCE WITH 1/3/6 HOUR VALUES AT AROUND 2/3/3.4 INCHES... LOWER IN THE URBAN CENTERS. ALL MODEL SOLUTIONS INDICATE THAT THE NEGATIVELY TILTED SHORT WAVE AND MID LEVEL TROUGH WILL LIFT OVER THE REGION THIS MORNING WITH THE BACK EDGE OF THE DEEP MOISTURE PLUME TO TRACK SW-NE THROUGH THE REGION BETWEEN LATE MORNING THROUGH THE MID AFTERNOON. THE SURFACE TROUGH AND WEAK LOW WILL ENHANCE CONVERGENCE OVER THE REGION TODAY LOCALLY ENHANCING RAINFALL. THE HEAVY RAIN THREAT WILL CONTINUE THROUGH THE LATE MORNING SW... AND INTO THE AFTERNOON EAST. QPF THROUGH THE REMAINDER OF THIS EVENT IS EXPECTED TO RANGE BETWEEN A HALF AND ONE INCH WITH LOCAL 2 INCH AMOUNTS. THE SOILS APPEAR TO BE ABLE TO HANDLE THE EXPECTED QPF. HOWEVER... THE HILLY AREA AND URBAN AREAS ESPECIALLY OVER THE NW PIEDMONT TRIAD ARE BECOMING MORE VULNERABLE IF 1 TO 1.5 INCH HOURS RATES DEVELOP... OR IF TRAINING DEVELOPS. WE WILL ISSUE A SPECIAL WEATHER STATEMENT TO ADDRESS THE THREAT AND WILL NOT ISSUE A WATCH AT THE CURRENT TIME. FOR TODAY... EXPECT NUMEROUS SHOWERS WITH LOCALLY HEAVY RAIN TAPERING FROM THE SW DURING THE DAY. SCATTERED SHOWERS AND AREAS OF DRIZZLE ARE EXPECTED BEHIND THE SURFACE TROUGH OVER THE WESTERN AREAS LATER THIS AFTERNOON. LONG TERM (TONIGHT THROUGH FRIDAY)... THE DEEP MOISTURE PLUME LIFTS NE AWAY FROM THE REGION TONIGHT WITH MID LEVEL DRYING. THE LOW LEVEL FLOW SHIFTS TO THE NNE AS THE SURFACE TROUGH MOVES TO THE COAST. THE LOW LEVEL NE FLOW WILL BE OVERRUN BY A SSW FLOW ALOFT. EXTENSIVE LOW CLOUDINESS WITH AREAS OF DRIZZLE EXPECTED TONIGHT AND SUNDAY. LOWS TONIGHT SHOULD BE SLOW TO FALL IN THE MOIST BOUNDARY LAYER (PREFER THE WARMER MET)... BUT TEMPS SUNDAY SHOULD REMAIN IN THE 60S NW TO 70S SE (CLOSER TO GFS). FOR SUNDAY NIGHT THROUGH MONDAY NIGHT... ENHANCED MOIST NE LOW LEVEL FLOW EXPECTED TO CONTINUE TO BE OVERRUN BY SW FLOW ALOFT. CHANCE OF MEASURABLE RAIN MAY INCREASE AGAIN DURING THIS PERIOD AS A H5 CIRCULATION APPROACHES FROM THE WEST... AND THE FRONT NEAR THE COAST REMAINS NEARLY STATIONARY. NO BIG CHANGE TO CURRENT FORECAST EXCEPT TO LOWER DAYTIME TEMPS DUE TO EXTENSIVE LOW CLOUDINESS EXPECTED. SOME DRYING EXPECTED BY MID WEEK AS THE MID AND UPPER FLOW IS FORECAST TO BECOME MORE WESTERLY. AVIATION... LITTLE CHANGE TO ONGOING IFR/LIFR CIG PATTERN IS EXPECTED THROUGH DAYBREAK... AND VSBYS AT ALL TAF SITES WILL LIKELY VARY BETWEEN P6SM AND 1SM TO 2SM IN MODERATE RAIN THROUGH 12Z. THE GFS'S SUPERIOR INITIALIZATION OF THE MID LEVEL VORTEX OVER THE GA/AL BORDER & BETTER DEPICTION OF CURRENT PRECIP MAKES IT THE PREFERRED SOLUTION. RAIN SHOULD BECOME MORE INTERMITTENT BY MIDDAY AS SLIGHT MID-UPPER LEVEL DRYING NOTED ON WATER VAPOR IMAGERY MOVES IN SOUTH TO NORTH. WILL RAISE CIGS TO MVFR IN THE AFTERNOON... THEN DROP THEM BACK DOWN TOWARD IFR AS THE LOWER COLUMN STABILIZES IN THE EVENING. -GIH && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...DJF nc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC 1009 AM EDT SAT OCT 8 2005 .SHORT TERM (REST OF TODAY)... COMPLEX UPPER PATTERN WITH CLOSED LOW IN MI...CUTOFF LOW IN OK...AND TROUGH IN GA/FL. SURFACE COLD FRONT STRETCHES NE TO SW BETWEEN FOOTHILLS AND PIEDMONT...AS EVIDENCED BY DEW POINT GRADIENT THERE. SATELLITE IMAGERY SHOWS SIGNIFICANT BREAK IN EXTENSIVE CLOUD COVER LEE OF MTS...WHERE DOWNSLOPE FLOW NOTED IN OBSEVATIONS. LOWERED SKY COVER PER SATELLITE IMAGERY. ALSO LOWERED POPS... ESPECIALLY IMMEDIATE LEE OF MOUNTAINS WHERE BEST DRYING OCCURRING. ADDED THUNDER EXTREME E WHERE MODEL CAPES REMAIN MARGINAL. DICOUNTED MODEL CAPES UPPER SAVANNAH VALLEY WHERE MODEL DEW POINTS REMAIN HIGHER THAN OBSERVED VALUES. RAISED MAX TEMPERATURES IN FOOTHILLS WHERE OBSERVATIONS ABOVE GUIDANCE...AND LOWERED TEMPERATURES IN MOUNTAINS WHERE OBSERVATIONS BELOW GUIDANCE. UPDATED DEW POINTS WITH OBSERVED VALUES THIS MORNING...HIGHER E AND LOWER W. ADJUSTED MAV TOO MOIST MID MORNING...AND ADJUSTED MET EVEN MORE MOIST...SO JUST REDUCED OBSERVED MORING DEW POINT BY A DEGREE OR SO. BY MID DAY ADJUSTED MAV ON TRACK WITH STEADY DRYING THROUGH AFTERNOON. UPDATED WIND FROM RUC WHHICH MAINTAINS WEAK DOWNSLOPE THROUGH DAY. && .PREVIOUS DISCUSSION... (ISSUED 548 AM EDT SAT OCT 8 2005) SHORT TERM (REST OF TODAY)... WILL UPDATE PUBLIC PRODUCTS AND GRIDS TO ALLOW WATCH TO EXPIRE AND TO LOWER POPS ACROSS THE FORMER WATCH AREA. WILL ALSO MAKE A FEW ADJUSTMENTS TO HIGH MOUNTAIN MAX TEMPS FOR TODAY GIVEN WARM START. PREVIOUS DISCUSSION... (ISSUED 307 AM EDT SAT OCT 8 2005) SHORT TERM (TODAY THROUGH MONDAY)... SFC LOW CENTER ANALYZED JUST WEST OF CHARLOTTE AT 06Z THIS MORNING...WITH RADAR SHOWING RAPIDLY DIMINISHING PRECIP COVERAGE ACROSS THE REGION. WILL CANCEL THE CURRENT FFA FOR SW SECTIONS THAT EXPERIENCED NO FLOODING FRIDAY...AND ALLOW REMAINDER OF FOOTHILL AND PIEDMONT LOCATIONS TO EXPIRE ON SCHEDULE AT 6 AM. THE GFS SOLUTION WILL BE HEAVILY PREFERRED THROUGH THE PERIOD...WITH BETTER MID LEVEL DRYING AS BOUNDARY VERY SLOWLY SLIDES EAST AND NE GULF UPPER VORT TRANSLATES UP THE ERN SEABOARD. MODELS AGREE FAIRLY WELL WITH THE NRN STREAM GREAT LAKES WAVE STAYING N OF THE REGION...WHILE THE LOWER MS VALLEY WAVE OPENS UP AND BRUSHES THE NC MTNS ON MONDAY. IN THE INTERIM...LOW LEVELS SHOULD REMAIN FAIRLY MOIST...AND A WEAK 850 MB LOW IS EXPECTED TO REDEVELOP SOMEWHERE WEST OF THE REGION TO BRING LIGHT UPGLIDE BACK IN THROUGH THE WEEKEND. WITH THE DEEPER MOISTURE DIMINISHING... HOWEVER...MEASURABLE RAINFALL SHOULD NOT BE ESPECIALLY WIDESPREAD BUT DRIZZLE AND LOW CLOUDS COULD REMAIN PERSISTENT. WILL ACCORDINGLY KEEP A FAIRLY SMALL DIURNAL RANGE ON TEMPS. SHOWER CHANCE MAY INCREASE SLIGHTLY ACROSS THE MTNS LATE SUN NIGHT AND MON AS VORT LIFTS OUT. LONG TERM (MONDAY NIGHT THROUGH FRIDAY)... THE DEEPER CLOSED LOW IN THE PLAIN SHOULD GRADUALLY OPEN UP AND LIFT NE TOWARD THE GREAT LAKES BY LATE WEEK. LIMITED PRECIP CHANCES UNDER WEAK SE RIDGING UNTIL LATE WEEK LOOKS VERY GOOD STILL AND NO CHANGES EXPECTED. AVIATION... STRONG DEEP LAYER FORCING IS GRADUALLY SHIFTING TO THE NORTH...WITH THREAT FOR RAINFALL AT TERMINALS RAPIDLY ENDING. THEREFORE...THE MAIN CONCERN FOR THE REMAINDER OF THE MORNING WILL BE THE FOG/ STRATUS POTENTIAL. KGSP VAD WIND PROFILE INDICATES NORTHERLY FLOW IN THE LOWEST 6K FEET OR SO. CIGS AT THE UPSTATE TERMINALS AND KAVL HAVE LIFTED TO MVFR/VFR IN THE PAST FEW HOURS...AND IN CONSIDERATION OF THIS WEAK DOWNSLOPE COMPONENT...WOULD EXPECT THEM TO STAY THERE FOR FOR THE REMAINDER OF THE MORNING. WILL JUST INDICATE FEW-SCT CLOUDS IN THE IFR RANGE. AT KCLT...WHICH SHOULD REMAIN EAST OF THE H8 TROUGH FOR THE REMAINDER OF THE MORNING...WILL CONTINUE AT LEAST TEMPOS FOR IFR. WITH EXTENSIVE CLOUD COVER AND WEAK MIXING (ESP ACROSS THE WEST)...DO NOT EXPECT VISBY TO BE A BIG PROBLEM THIS MORNING...AND WITH ALL 4 TERMINALS ALREADY WELL INTO THE VFR RANGE...WILL LIMIT VISBY RESTRICTIONS TO THE UPPER END OF MVFR. && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SHORT TERM...JAT sc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE JACKSON KY 200 PM EDT SAT OCT 8 2005 .DISCUSSION... TONIGHT THROUGH TUESDAY...12Z SOUNDINGS SHOW INVERSION WITH MOISTURE TRAPPED BELOW 800 MB. MODEL SOUNDINGS IN AREEMENT WITH KEEPING LOW LEVEL MOISTURE IN PLACE TRAPPED BELOW INVERSION THROUGH SUNDAY NIGHT. LOW LEVEL NORTHEAST FLOW TO CONTINUE AS WELL. ALL THIS POINTS TO WIDESPREAD CLOUD COVER. WITH LOW LEVEL OVERCAST TO CONTINUE FEEL THE MAV AND MET MOS A LITTLE COOL ON LOWS TONIGHT AND HAVE OPTED TO KEEP GRIDDED FORECAST TEMPERATURES FOR TONIGHT CLOSE TO WHAT WE ALREADY HAD. WITH CONSIDERABLE CLOUD AGAIN SUNDAY FEEL THAT MAV MOS MAXIMUMS ARE TOO HIGH. HOWEVER NOT AS COOL AS MET MOS WHICH HAS HIGHS ON SUNDAY AROUND 10 DEGREES LOWER THAN EITHER THE FWC OR MAV. MET MOS LOOKS TO BE TOO COOL OVERALL WITH BOTH HIGHS AND LOWS. FOR SUNDAY NIGHT INTO TUESDAY TEMPERATURES WILL BE DEPENDENT ON SKY COVER...AND HAVE OPTED TO CONTINUE WITH CLOSE TO THE CURRENT FORECAST GRIDS. FOR WEATHER HAVE DROPPED POPS FOR THIS EVENING TO LESS THAN SLIGHT CHANCE...BUT WILL LIKELY GO WITH PATCHY DRIZZLE OVER EASTERN FORECAST AREA FOR THIS EVENING. NEXT WEATHER FEATURE TO WATCH IS THE MID/UPPER LEVEL LOW SHOWING UP NICELY ON WATER VAPOR SATELLITE IMAGERY OVER TEXAS. ALL MODELS...DESPITE SOME DIFFERENCES ON TIMING AND STRENGTH BRING LOW AND SHORT WAVE TROF NORTHEAST. NAM AND GFS SHOW VERY LITTLE MID AND UPPER LEVEL MOISTURE...AND THE MAV MOS REMAINS BELOW 20 PCT FOR SUNDAY NIGHT INTO MONDAY NIGHT. EVEN THOUGH THE NAM ALSO SHOWS LIMITED LIFT AND MOISTURE THE MET MOS IS 30 TO 40. CHANCE OF MEASURABLE RAIN LOOKS LIMITED BUT WITH APPROACH OF MID/UPPER LOW DO NOT WANT TO DROP POPS TO LESS THAN SLIGHT CHANCE. HAVE OPTED TO GO WITH CONTINUITY...AND WILL CONTINE WITH THE 20 TO 30 POPS WE HAD IN THE GRIDS FOR SUNDAY NIGHT INTO MONDAY. FOR THE PERIOD WEDNESDAY THROUGH SATURDAY... MODEL OF PREFERENCE WAS GFS. ONLY A FEW MINOR CHANGES MADE TO EXTENDED. MADE A FEW TWEAKS TO SKY COVER...PRECIPITATION PROBABILITY...AND WEATHER GRIDS PER LATEST MODEL DATA. PREVIOUS FORECAST LOOKED PRETTY GOOD AS WELL...SO NEW MODEL DATA WAS MASSAGED TO AGREE MORE WITH PREVIOUS FORECAST TRENDS. BOTH GFS AND ECMWF MODELS BRINGING A STRONG SHORTWAVE ACROSS THE CENTRAL UNITED STATES WEDNESDAY NIGHT THROUGH FRIDAY. WITH AMPLE LOW AND MIDDLE LEVEL MOISTURE SHOWING UP IN MODEL CROSS SECTIONS AND SOUNDINGS...FELT CHANCE POPS WERE STILL WARRANTED FOR LATE WEEK. MODELS INDICATE THAT SHORTWAVE WILL EXIT EASTERN KENTUCKY SOMETIME NEXT SUNDAY. LOOK FOR PARTLY TO MOSTLY CLOUDY SKIES NEXT WEEK...WITH RAIN CHANCES EACH DAY THROUGH FRIDAY NIGHT. TEMPERATURES AND DEWPOINTS LOOKED GOOD AND WERE NOT CHANGED. WINDS NEEDED TO BE TWEAKED SLIGHTLY TO BETTER REFLECT THE PASSAGE OF THE SHORTWAVE/SURFACE FRONT LATE NEXT WEEK. && .PREV DISCUSSION... 1027 AM EDT SAT OCT 8 2005 LOW LEVEL NORTHEAST FLOW...WITH SATELLITE SHOWING LOW CLOUD SPREADING SOUTHWEST ACROSS WESTERN KY. BASED ON CURRENT TRENDS AND LATEST RUC AND 06Z NAM SHOWING LOW LEVEL MOISTURE REMAINING IN PLACE ACROSS EAST KY...HAVE INCREASED SKY COVER IN THE NEAR TERM GRIDS. WAS ALREADY OVERCAST TODAY IN THE GRIDS BUT HAVE INCREASED SKY COVER FOR TONIGHT AND SUNDAY AS WELL. TEMPERATURES LOOK ON TARGET FOR TODAY WITH CURRENT TEMPERATURES RUNNING CLOSE TO GRIDDED FORECAST. MOSTLY DRIZZLE TO FALL OUT OF SHALLOW CLOUD DECK TODAY...BUT HAVE LEFT IN LOW CHANCE POPS FOR MEASUREABLE LIGHT RAIN AS LOZ DID MEASURE ONE-HUNDREDTH OF AN INCH WITH -RA THIS MORNING. UPDATED PRODUCT FORECAST SUITE IN THE PROCESS OF BEING TRANSMITTED. 520 AM EDT SAT OCT 8 2005 SFC CHART THIS MORNING SHOWING HIGH PRESSURE OVER THE GREAT LAKES...AND WAVY FRONTAL BOUNDARY LAYING ROUGHLY ALONG THE SPINE OF THE APPALACHIANS. SATELLITE SHOWING PLENTY OF CLOUD COVER ACROSS THE REGION AND WATER VAPOR IS SHOWING A FAIRLY POTENT SHORTWAVE MOVING SLOWLY THROUGH THE MIDWEST. RADAR AND SFC OBS INDICATE A SWATH OF LIGHT RAIN MOVING INTO THE UPPER OHIO VALLEY...WITH PATCHY DRIZZLE IN ITS WAKE AND LIGHT RAIN SHOWERS FURTHER WEST ASSOCIATED WITH SHORTWAVE. MODELS WERE IN DECENT AGREEMENT WITH TWO MAIN SHORT WAVES TO CONTEND WITH. THE FIRST MOVES THROUGH THE AREA TODAY. THE SECOND PUSHES ACROSS THE TN VALLEY AND INTO THE OHIO VALLEY LATE SUNDAY NIGHT AND MONDAY. BEST ESTIMATE WOULD PUT THE SHORTWAVE THROUGH EASTERN KENTUCKY BY EARLY MONDAY AFTERNOON. DECIDED TO INCREASE MONDAYS SLIGHT POPS TO LOW CHANCE WITH HIGHEST POPS SLATED FOR THE MID MORNING PERIOD. NOT REALLY EXPECTING MUCH IN THE WAY OF PRECIPITATION TODAY...BUT LEFT A SLIGHT POP IN THE FORECAST FOR THE AREA UNTIL THE SHORT WAVE COMPLETES ITS PUSH THROUGH THE REGION. AXIS OF UPPER AIR TROUGH WILL HAVE MADE IT THROUGH THE AREA BY THIS AFTERNOON...SO WENT WITH MAINLY MORNING TYPE WORDING FOR PRECIP IN THE ZONES. ALSO LEFT HIGHER POPS IN THE EAST WITH SHOWERS STILL SHOWING UP ON RADAR MOVING NORTHEAST FROM TN AND VA. VERY CURIOUS AT HOW MOS GUIDANCE WAS SO DIFFERENT...WITH OVERALL FEATURES IN THE MODEL RUNS BEING QUITE SIMILAR. THIS MADE FOR A DIFFICULT TEMP FORECAST. LOOKING OVER TIME HEIGHT SERIES AND FCST SOUNDINGS...EXPECT SUBSIDENCE BEHIND THE SHORTWAVE TO DRY OUT THE MID AND UPPER LEVELS OF THE ATMOSPHERE TODAY. HOWEVER...MODELS AGREE ON A VERY MOIST AND CLOUDY BOUNDARY LAYER. UPSLOPE FLOW WILL HELP TO GUARANTEE THIS FOR AT LEAST MOST OF THE DAY. BUT CAN NOT RULE OUT A PEAK AT THE SUN IN THE SOUTHWEST THIS AFTERNOON. CONSEQUENTLY WENT WITH COOLER AFTERNOON HIGHS THAN MAV MOS ADVERTISED...BUT WARMER THAN WHAT APPEARS TO BE THE MET MOS PRECIP COOLED TEMPS. LEANED TOWARDS WARMER OVERNIGHT LOWS TONIGHT AS CLOUD COVER SHOULD STILL BE SUBSTANTIAL. THEREAFTER...LEANED TOWARDS MAV MOS TEMPS AS IT HAS RECENTLY BEEN PERFORMING BETTER THAN THE MET AND FWC MOS. 955 PM EDT FRI OCT 7 2005 AREAS OF LIGHT RAIN CONTINUE TO PERSIST IN THE FAR EASTERN SECTIONS OF THE FORECAST AREA IN REGION OF MID LEVEL DEFORMATION ZONE...WHICH IS FORECAST TO SHIFT EAST OVERNIGHT. WHILE NO MEASURABLE PRECIPITATION IS FALLING ACROSS THE WESTERN 2/3RDS OF THE FORECAST AREA...ISENTROPIC LIFT ALONG 310K SFC IS FORECAST TO INCREASE AFTER 6Z AS UPPER LEVEL SHORTWAVE CURRENTLY ACROSS SE MICHIGAN AND ASSOCIATED UPPER TROF APPROACH. THEREFORE WILL KEEP POPS FOR THIS AREA...BUT WILL LOWER THEM. ALSO WILL KEEP MENTION OF DRIZZLE THROUGH THE OVERNIGHT HOURS. FOR CONTINUITY PURPOSES...LOWERED POPS SATURDAY AS WELL. OTHERWISE...NO MAJOR CHANGES WERE MADE TO TEMPS/WINDS/CLOUD COVER. && .JKL WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SBH/RICHEY ky AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 328 PM EDT SAT OCT 8 2005 .DISCUSSION... TRANQUIL PERIOD OF WEATHER IS GETTING UNDERWAY. MAIN FCST ISSUE WILL BE CLOUD COVER OVER THE NEXT 12-24HRS UNTIL LOW-LEVEL MOISTURE MIXES OUT AND TEMPS MODERATE ENOUGH TO END LAKE GENERATED CLOUDINESS. WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A SHORTWAVE DROPPING INTO THE SWRN STATES WITH RIDGE BUILDING DOWNSTREAM ACROSS THE CNTRL CONUS INTO ONTARIO. A MIDLEVEL LOW WAS OVER TX. VIS SATELLITE IMAGERY SHOWED WIDESPREAD STRATOCU/STRATUS DOWNWIND OF THE GREAT LAKES IN GENERAL ERLY LOW-LEVEL FLOW WITH SFC HIGH PRES RIDGE AXIS EXTENDING FROM JAMES BAY ACROSS CNTRL UPPER MI TO SW WI. 12Z KAPX SOUNDING SHOWED A VERY SHARP INVERSION BASED AT 895MB (3.6KFT MSL) WITH -4C TEMP AT BASE OF INVERSION PLENTY COLD ENOUGH TO SUPPORT EXTENSIVE LAKE EFFECT CLOUDINESS. AIRMASS IS VERY DRY ABOVE INVERSION WITH DWPT DEPRESSIONS INCREASING TO 22C AT 800MB AND TO 39C AT 750MB. ACROSS LAKE MICHIGAN AT KGRB...SOUNDING SHOWED A WARMER TEMP PROFILE WITH INVERSION BASED AT 825MB (5.7KFT MSL). DURING THE LAST COUPLE OF HRS...AREAL COVERAGE OF CLOUDS HAS BEEN RAPIDLY DECREASING DUE TO LOW-LEVEL TEMP MODERATION AND MIXING OUT OF MOISTURE INTO THE VERY DRY AIR ABOVE INVERSION BASE. ONLY AREAS IN UPPER MI STILL AFFECTED BY OVERLAKE TRAJECTORIES ARE LIMITED TO THE KEWEENAW AND FAR SRN MENOMINEE COUNTY. TRANQUIL WEATHER WILL BE THE RULE OVER THE NEXT FEW DAYS AS MID/UPPER LEVEL RIDGE SETS UP OVER THE UPPER GREAT LAKES REGION... KEEPING SHORTWAVES WELL NW/N OF HERE AND MID LEVEL LOW OVER TX TO THE S AS IT UNDERCUTS RIDGE. THIS LEAVES TEMPS/CLOUDS AS THE ONLY FCST ISSUES. GFS/NAM SHOW SFC RIDGE AXIS REMAINING NEARLY STATIONARY TONIGHT...BUT WITH LOW-LEVEL WINDS VEERING SLIGHTLY MORE TO THE ESE OVER NRN LAKE MICHIGAN. THIS BRINGS CONCERN FOR STRATUS/STRATOCU EXPANDING INTO SCNTRL/SW FCST AREA. GFS/NAM FCST SOUNDINGS OVER NRN LAKE MICHIGAN SHOW TEMP AT BASE OF INVERSION AROUND 5C TONIGHT...BUT THIS MAY BE A BIT TOO HIGH AS BOTH MODELS WERE 2C TOO WARM WITH TEMP AT INVERSION BASE OVER NCNTL LWR MI BASED ON 12Z KAPX SOUNDING. IN ANYCASE...WITH SFC WATER TEMP AROUND 16C...INSTABILITY WILL BE SUFFICIENT FOR CONTINUED STRATUS/STRATOCU OFF THE LAKE. IN ADDITION...JUST THE SIMPLE ACT OF UPSLOPING THE LAKE MODIFIED AIR INTO SCNTRL UPPER MI WOULD LEAD TO STRATUS DEVELOPMENT EVEN IF THE LOW-LEVEL TEMP PROFILE WAS SEVERAL DEGREES WARMER. SO...WILL TREND SKY GRIDS TOWARD THE DEVELOPMENT OF CLOUDS OVER THE SCNTRL FCST AREA WHERE FLOW WILL BE UPSLOPING. TO THE W...FLOW VEERS MORE SRLY WHICH SHOULD BRING AN END TO LAKE EFFECT CLOUDS AFFECTING THE KEWEENAW... EXCEPT PERHAPS THE VERY TIP OF THE KEWEENAW. WHERE SKIES ARE EXPECTED TO BE CLEAR/MOSTLY CLEAR...HAVE KEPT MINS CLOSE TO GOING FCST WHICH IS ON THE LOW SIDE OF VARIOUS MOS GUIDANCE (REASONABLE FOR NEARLY IDEAL RADIATIONAL COOLING CONDITIONS). HAVE BUMPED UP MINS A LITTLE OVER THE S WHERE CLOUDS ARE EXPECTED TO DEVELOP. MODERATING TEMP PROFILE AND CONTINUAL MIXING OUT OF LOW-LEVEL MOISTURE SHOULD LEAD TO INCREASING SUNSHINE SUNDAY WHERE THE DAY STARTS OUT WITH SOME CLOUDS. VIS SATELLITE IMAGERY THIS AFTN SHOWS NO CU DEVELOPMENT OUTSIDE OF AREAS WHERE LOW LEVELS ARE MOISTENED BY FLOW ACROSS ANY OF THE GREAT LAKES. SO EXPECT LITTLE OR NO CU DEVELOPMENT...AND THIS IS SUPPORTED BY FCST SOUNDINGS. MIXING TO AROUND 900MB ON FCST SOUNDINGS SUGGESTS HIGHS GENERALLY IN THE UPPER 50S SUN...WHICH IS SIMILAR TO GOING FCST AND VARIOUS MOS GUIDANCE. WITH CLEAR SKIES AND LITTLE WIND MON NIGHT...HAVE FAVORED LOWER END OF MOS GUIDANCE. BUILDING UPPER RIDGE WILL SUPPORT REDEVELOPMENT OF SFC HIGH PRES INTO WRN ONTARIO MON...RESULTING IN STRENGTHENING NERLY FLOW. APPEARS THAT LOW-LEVEL TEMP PROFILE WILL BE WARM ENOUGH TO PREVENT DEVELOPMENT OF STRATOCU IN UPSLOPING FLOW OFF LAKE SUPERIOR. WILL BE SOMETHING TO KEEP AN EYE ON THOUGH SINCE THE NAM SHOWS POTENTIAL FOR CLOUDS TO DEVELOP. OTHERWISE...SINCE GFS/NAM FCST SOUNDINGS SHOW A SLIGHTLY WARMER LOW-LEVEL TEMP PROFILE MON...HIGHS INLAND SHOULD BE A COUPLE OF DEGREES WARMER THAN SUN. NERLY FLOW SHOULD RESULT IN HIGHS ABOUT THE SAME AS SUN FOR AREAS NEAR LAKE SUPERIOR. MID LEVEL RIDGING WILL PERSIST MON NIGHT/TUE...PROVIDING CONTINUED QUIET WEATHER WITH ERLY LOW-LEVEL WINDS DUE TO SFC HIGH PRES LOCATED TO THE NE OF LAKE SUPERIOR. EXPECT MINS IN THE UPPER 30S/LWR 40S MON NIGHT WITH HIGHS TUE GENERALLY AROUND 60 UNDER MOSTLY SUNNY SKIES. WED THRU SAT...CANADIAN/UKMET/ECMWF/GFS CONTINUE TO REMAIN IN REASONABLE AGREEMENT ON THE PATTERN...BUT GFS/ECMWF ARE AGAIN MOST SIMILAR. PCPN POTENTIAL EARLY IN THIS PERIOD IS RELATED TO MIDLEVEL LOW OVER THE WRN PLAINS TUE THAT OPENS UP AND WEAKENS WHILE LIFTING NE INTO THE GREAT LAKES WED/THU. GIVEN GOOD MODEL RUN-TO-RUN CONTINUITY THE LAST FEW DAYS ON THIS SYSTEM...WILL MAINTAIN THE GOING FCST OF CHC POPS LATER WED INTO THU AS SYSTEM CROSSES THE AREA. VERY LIMITED MOISTURE AVBL TO THIS WEAKENING SYSTEM SUGGESTS IT VERY WELL COULD PASS THRU THE AREA WITH NO PCPN...THUS ONLY LOW END CHC POPS WILL CONTINUE TO BE USED. PREVIOUS GFS RUNS INCLUDING 00Z/07 REFORECAST ENSEMBLES INDICATED ANOTHER SHORTWAVE/COLD FRONT DROPPING INTO THE AREA FRI. 00Z/08 GFS BACKED OFF ON THAT SHORTWAVE DROPPING AS FAR SE...BUT 06Z GFS TRENDED BACK TOWARD PREVIOUS RUNS. ECMWF DOES NOT SHOW THIS SHORTWAVE...BUT IT IS LESS PROGRESSIVE MOVING THE PREVIOUS TROF EWD. WITH LOW CONFIDENCE...WILL TREND TOWARD THE SLOWER PROGRESSION PER HPC DISCUSSION...AND WILL GO WITH A DRY DAY ON FRI. LEANING TOWARD SLOWER ECMWF PROGRESSION...NEXT SHORTWAVE AND COLD FRONT SHOULD ARRIVE LATER SAT. TEMPS THRU THE PERIOD SHOULD REMAIN AT OR ABOVE NORMAL...GENERALLY HIGHS IN THE MID 50S TO AROUND 60 WITH LOWS IN THE MID 30S TO LWR 40S. && .MQT...WATCHES/WARNINGS/ADVISORIES...NONE. && $$ ROLFSON mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 326 PM EDT SAT OCT 8 2005 .SHORT TERM...TONIGHT AND SUNDAY PESKY LOW STRATUS AND UPPER LOW CONTINUE TO PLAGUE THE REGION WITH RECENT TRENDS SEEN IN THE 1KM VISIBLE QUITE PROMISING BUT WILL TAKE THIS WITH CAUTIOUS OPTIMISM. RADAR IMAGERY ALL DAY HAS SLOWLY SHOWN SOME SHOWERS INFILTRATING FROM KPHN-KTFF AND AS LONG AS THIS UPPER LOW REMAINS IN OUR VICINITY...WE WILL NEED TO KEEP THE MENTION OF LIGHT SHOWERS THROUGH EARLY THIS EVENING FOR THOSE EASTERN COUNTIES. LATEST RUC SEEMS TO HAVE THE BEST HANDLE IN THE IMMEDIATE SHORT TERM AND BY 10-11PM... EXPECT SHOWERS TO BE FURTHER SOUTH TOWARD KDET-KTTF THEN EITHER DISSIPATE OR BE SOUTH OF THE CWA BY MIDNIGHT. THEN WE ARE LEFT WHAT TO DO WITH CLOUD COVER FOR THE REMAINDER OF THE OVERNIGHT. VARIETY OF NUMERICAL SOLUTIONS ARE SUGGESTING WE WILL LOSE THE STRATUS (AS CURRENTLY SEEN) WITH THE MAIN CONCENTRATION ACROSS THE TRI CITIES AND THUMB. YET AS THIS UPPER LOW WEAKENS AND TRANSLATES SOUTH...SUBSIDENCE WILL NOT BE AS STRONG AND NOCTURNAL INVERSION DEVELOPS WITH STEEP LAPSE RATES OFF THE LAKE BELOW THE INVERSION. SO COULD SEE STRATUS RE-DEVELOP AND SPREAD ACROSS THE MOST OF THE CWA OVERNIGHT. WE WILL AVERAGE TEMPERATURES OVERNIGHT TO AROUND 40F WITH THE WARMER VALUES NEAR DETROIT AND LAKE SHORES...COOLER WELL INLAND. SUNDAY...MODELS ATTEMPT TO FURTHER DECOMPOSE THE UPPER LOW WITH THE NAM MORE PESSIMISTIC WITH MID LEVEL MOISTURE THAN THE GFS/WRF. GIVEN OUR RECENT TRENDS, WE WILL FAVOR CLOSER TO THE NAM BUT EITHER WAY...A DRY DAY. EVEN WITH THE SUNSHINE...MIXING LAYER HEIGHTS ARE QUITE SHALLOW AND WOULD SUGGEST HIGH TEMPERATURES REMAINING IN THE LOWER 60S. NORTHEAST FLOW TRAJECTORY BECOMES A LITTLE MORE EAST WITH TIME TO ASSIST WITH SOME DRIER AIR FILTERING INTO THE STATE AT THE LOWER LEVELS. && .LONG TERM...SUNDAY NIGHT THROUGH SATURDAY SURFACE HIGH PRESSURE/RIDGE PREVAILING NORTH OF THE GREAT LAKES THROUGH EARLY WEEK WITH OCCASIONAL PUNCHES NORTHWARD INTO EASTERN STATES OF INVERTED TROUGHINESS. AT 500 MB...WEAKENED VORTICITY LOBE/TROUGH VIA GOOD MODEL CONSENSUS GETTING PUSHED BACK NORTH INTO/ACROSS FORECAST AREA SUNDAY NIGHT/MONDAY AS A WELL DEFINED SHORTWAVE TROUGH CURRENTLY SEEN VIA WATER VAPOR IMAGERY OVER TX GETS NUDGED NORTHEAST ON UP INTO SOUTHEASTERN GREAT LAKES REGION EARLY IN WEEK. MODEL CONSENSUS THEN SHOWS THIS SHORTWAVE TROUGH RETREATING SLOWLY EAST/NORTHEAST...ALBEIT WITH MODEL TO MODEL DIFFERENCES IN TIMING...AS BRIEF SHORTWAVE RIDGING SETS UP OVERHEAD IN ITS WAKE. LOW TO MID LEVEL RELATIVE HUMIDITY FIELDS SHOW MOISTURE MAINLY CONFINED TO EAST/SOUTHEAST COUNTIES AT BEST SUNDAY NIGHT INTO TUESDAY...WITH NAM MORE ROBUST WITH RESPECT TO MOISTURE THAN GFS. AT 925 MB...INCREASING RELATIVE HUMIDITY SUNDAY NIGHT AND MONDAY THEN CONTINUING THROUGH TUESDAY. LOW TO MID LEVEL EASTERN THETA E RIDGE NUDGES EASTERN COUNTIES THROUGH EARLY WEEK...FOLLOWING THETA E ADVECTION INTO FORECAST AREA FROM THE EAST SUNDAY NIGHT. MODELS SHOW SLIGHT AT BEST LOW TO MID LEVEL OMEGA LIFT SUNDAY NIGHT AND MONDAY...THEN MOSTLY WEAK SUBSIDENCE THROUGH TUESDAY. WEAK 850 TO 500 MB QVECTOR CONVERGENCE WORKING BACK INTO FORECAST AREA BY MONDAY AND LINGERING MONDAY NIGHT. GFS SHOWS WEAK 850 TO 700 MB DEFORMATION OVER AREA MONDAY/TUESDAY...AND MODELS SHOW SURFACE CONVERGENCE PERSISTING EARLY PART OF WEEK BUT ESPECIALLY IN THE EASTERN COUNTIES. WILL CONTINUE FORECAST VIRTUALLY IDENTICAL TO EARLIER...KEEPING CHANCE OF SHOWERS IN EASTERN PART OF FORECAST AREA MONDAY THROUGH TUESDAY...AND WITH ALSO VERY LITTLE CHANGE IN PREVIOUS TEMPERATURE FORECASTS. AFTER EARLY WEEK...SOME CONSENSUS SHOWING MORE IN WAY OF BROADENED SURFACE INVERTED TROUGHINESS DEVELOPING NORTHWARD INTO FORECAST AREA BY THURSDAY AND CONTINUING FRIDAY...THOUGH THERE EXISTS GREAT VARIATION IN DETAILS AMONG MODELS...INCLUDING RUN TO RUN CHANGES...GOING INTO THE WEEKEND. AFTER MID WEEK...WESTERN MID LEVEL LOW OPENS UP AND ADVANCES INTO LAKES REGION FOR THE END OF THE WEEK. LOTS OF MODEL VARIATION AS TO TIMING OF THIS SYSTEM ON TO THE EAST AS WELL...BUT PREFER MODEL CONSENSUS OF DRY CONDITIONS BY SATURDAY. UNDER THE INFLUENCE OF MOISTURE/TROUGH...WILL RETAIN CHANCE MENTION OF SHOWERS WEDNESDAY NIGHT THROUGH FRIDAY...WITH GUIDANCE TEMPERATURES IN THE BALL PARK. && .AVIATION...ISSUED 115 PM EDT SAT VERY DIFFICULT CLOUD FORECAST THIS AFTERNOON INTO TONIGHT. H2O VAPOR LOOP SHOWS UPPER LOW JUST SOUTH OF THE STATE LINE WITH A SHARP MOISTURE GRADIENT SEEN IN THE MIDDLE LEVELS. NORTHEAST SFC FLOW CONTINUES ACROSS THE WARM WATERS OF LAKE HURON WITH AMPLE LAKE INDUCED STRATUS. HOWEVER...RECENT TRENDS IN THE SATELLITE IMAGERY SHOWING SOME OF THE DRIER AIR UPSTREAM FILTERING SOUTHWEST AND THIS MIGHT BE A SLOW PROGRESSING TREND THROUGH THE TAF PERIOD. NUMERICAL MODELS ARE NOT DOING WELL AS ALL OF THEM TOO QUICKLY ERODE THIS STRATUS LAYER. WE WILL HOLD ONTO THESE MVFR CEILINGS WITH A BKN DECK AND ATTEMPT TO SLOWLY CLEAR THINGS OUT OVERNIGHT INTO SUNDAY MORNING. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...SMALL CRAFT ADVISORY...SAGINAW BAY AND THE NEARSHORE WATERS FROM PORT AUSTIN TO PORT HURON...UNTIL 6 PM SUNDAY. LAKE ST CLAIR...NONE. MI WATERS OF LAKE ERIE...SMALL CRAFT ADVISORY...LEZ444...UNTIL 6PM SUNDAY. && $$ SHORT TERM...BGM LONG TERM....DWD AVIATION...BGM mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 115 PM EDT SAT OCT 8 2005 .AVIATION... VERY DIFFICULT CLOUD FORECAST THIS AFTERNOON INTO TONIGHT. H2O VAPOR LOOP SHOWS UPPER LOW JUST SOUTH OF THE STATE LINE WITH A SHARP MOISTURE GRADIENT SEEN IN THE MIDDLE LEVELS. NORTHEAST SFC FLOW CONTINUES ACROSS THE WARM WATERS OF LAKE HURON WITH AMPLE LAKE INDUCED STRATUS. HOWEVER...RECENT TRENDS IN THE SATELLITE IMAGERY SHOWING SOME OF THE DRIER AIR UPSTREAM FILTERING SOUTHWEST AND THIS MIGHT BE A SLOW PROGRESSING TREND THROUGH THE TAF PERIOD. NUMERICAL MODELS ARE NOT DOING WELL AS ALL OF THEM TOO QUICKLY ERODE THIS STRATUS LAYER. WE WILL HOLD ONTO THESE MVFR CEILINGS WITH A BKN DECK AND ATTEMPT TO SLOWLY CLEAR THINGS OUT OVERNIGHT INTO SUNDAY MORNING. BGM && .UPDATE... ISSUED AT 619 AM EDT WILL ISSUED A QUICK UPDATE TO REMOVE ALL MENTION OF SUNSHINE TODAY IN THE FAR SOUTHERN COUNTIES. THE BREAKS IN THE OVERCAST AROUND MONROE COUNTY HAVE COMPLETELY FILLED IN. BASED ON THE STRENGTH OF THE INVERSION... THESE CLOUDS SHOULD HANG AROUND FOR MUCH OF THE DAY. && .SHORT TERM...TODAY AND TONIGHT THE UPPER AIR PATTERN WILL BECOME MORE AMPLIFIED ACROSS NORTH AMERICA THROUGH THE SHORT TERM AS A STRONG UPPER JET NOSING INTO THE WEST COAST CARVES OUT DEEP TROUGH OVER THE WESTERN US BY SUN MORNING. MEANWHILE... A MID LEVEL CIRCULATION OVER THE SOUTHERN GREAT LAKES WILL SLOWLY MOVE INTO EASTERN OHIO TONIGHT...ALLOWING A MID LEVEL RIDGE TO BUILD ACROSS LOWER MICHIGAN TONIGHT. AN UPPER LOW OVER THE SOUTHEASTERN US WILL LIFT NORTH ALONG THE COAST. THE WATER VAPOR SHOWS A NICE PLUME OF TROPICAL MOISTURE STREAMING INTO THE MID ATLANTIC AND NORTHEAST US. THIS MOISTURE AND LIFT FROM THE SOUTHEASTERN WAVE WILL REMAIN EAST OF THE FORECAST AREA. WITH PERSISTENT NORTHEASTERLY FLOW ACROSS SE MICHIGAN TODAY... STRATUS WILL REMAIN THE MAIN FORECAST CONCERN THROUGH THE SHORT TERM. THE 00Z DTX SOUNDING SHOWED A STRONG INVERSION BASED NEAR 5K FEET. STRONG LOW LEVEL INSTABILITY OVER LAKE HURON HAS ALLOWED QUITE A BIT OF MOISTURE TO BECOME TRAPPED UNDERNEATH THIS INVERSION... RESULTING IN WIDESPREAD STRATUS ACROSS SOUTHEAST MICHIGAN. NORTHEASTERLY FLOW WILL PERSIST ACROSS LAKE HURON AND SOUTHEAST MICHIGAN TODAY. OF THE 00Z MODEL SUITE...THE RUC WAS THE ONLY SOLUTION TO HAVE A REASONABLE HANDLE ON THE STRENGTH AND DEPTH OF THE INVERSION. THE RUC HOWEVER SEEMS TO DRY OUT THE LOW LEVELS TOO QUICKLY. GIVEN THERE WILL BE SOME WEAK WARM AIR ADVECTION NEAR 850MB TODAY AND PERSISTENT NORTHEAST FLOW AND INSTABILITY OFF LAKE HURON... THINK THESE CLOUDS ARE GOING TO TAKE QUITE A WHILE TO DISSIPATE. THERE HAS BEEN SOME BREAKS IN THE CLOUDS OVERNIGHT ACROSS MONROE COUNTY. WITH THE ONSET OF DAYTIME HEATING... THIS MAY ALLOW SOME OF THE CLOUDS TO ERODE ACROSS THE SOUTH. NORTH-NORTHEASTERLY FLOW WILL ALSO ADD SOME DOWNSLOPE INTO WAYNE COUNTY. SO WILL CONTINUE TO HAVE THE CLOUDS BREAK UP A BIT ACROSS THE SOUTH. AS FOR THE REST OF THE FORECAST AREA... WILL KEEP SKIES MOSTLY CLOUDY THROUGH THE DAY. WILL THUS SIDE ON THE LOW END OF GUIDANCE MAX TEMPS...KEEPING MOST LOCALS IN THE 50S. THE LOW LEVEL FLOW WILL BECOME MORE EASTERLY TONIGHT...WHICH SHOULD FOCUS THE BEST POTENTIAL FOR LAKE EFFECT CLOUDS NORTH OF THE FORECAST AREA. MID LEVEL SUBSIDENCE WILL ALSO STRENGTHEN ACROSS LAKE HURON. SOME WARM AIR ADVECTION NEAR 925MB COUPLED WITH THE MID LEVEL SUBSIDENCE SHOULD WEAKEN THE INVERSION TONIGHT. MUCH DRYER LOW LEVEL AIR WILL ALSO ADVECT ACROSS LAKE HURON AND SHOULD EVENTUALLY WORK ITS WAY INTO SE MICHIGAN. SO WILL CONTINUE TO FORECAST A CLEARING TREND TONIGHT. DESPITE THE CLEARING... ENOUGH OF A GRADIENT SHOULD BE IN PLACE ACROSS SE MICHIGAN TO KEEP TEMPS FROM DROPPING TO NEAR FREEZING. GUIDANCE MIN TEMPS OF UPPER 30S TO LOWER 40S THUS LOOK REASONABLE. && .LONG TERM... LATEST WATER VAPOR IMAGERY INDICATING A CLOSED CIRCULATION OVER NORTH CENTRAL TEXAS. THIS FEATURE IS CURRENTLY EMBEDDED WITHIN A DRY AIRMASS AND IS ESSENTIALLY INACTIVE AT THE MOMENT. THIS SHOULD CHANGE AS THE SYSTEM INTERACTS WITH THE LEFTOVER MOISTURE ALONG THE EAST COAST EARLY NEXT WEEK. THE UPPER LOW WILL HEAD INTO LOWER MISSISSIPPI VALLEY BY SUNDAY...GRADUALLY LIFTING NORTH/NORTHEAST AS A MUCH STRONGER UPPER LOW MOVES INTO THE SOUTHERN ROCKIES. THE KEY TO THE FORECAST IS DETERMINING HOW MUCH MOISTURE WILL ADVECT IN FROM THE EAST...AS 500 MB LOW APPROACHES FROM THE SOUTH ON MONDAY. MODEL CONSENSUS (GFS/UKMET/CANADIAN/NOGAPS) FORECASTING THE SYSTEM TO TRACK INTO THE EASTERN GREAT LAKES MONDAY NIGHT/TUESDAY. THIS IS IS PRETTY MUCH WHAT YESTERDAY'S WRFXX RUN HAD. ALTHOUGH...TONIGHT'S WRFXX RUN STALLS THE UPPER LOW OVER OHIO. MAJORITY OF MODELS ARE SIGNIFICANTLY FATHER EAST THAN THE CURRENT 00Z NAM FORECASTED POSITION OVER CHICAGO. WITH THE EASTERN TRACK FAVORED...TOUGH CALL WHETHER OR NOT PRECIPITATION WILL WRAP BACK THIS FAR WEST (ESPECIALLY WITH MODELS TRENDING FATHER EAST). NONE-THE-LESS...STILL WORTHY OF LOW CHANCE POPS CHANCE POPS ACROSS THE EASTERN HALF OF THE CWA (MONDAY THROUGH TUESDAY)...PER CURRENT FORECAST. JUST MADE SOME MINOR TWEAKS TO TEMPERATURES TO LOWER THE DIURNAL RANGE BASED ON THE CONSIDERABLE CLOUD COVER EXPECTED. SHORTWAVE RIDGING OVER THE CENTRAL GREAT LAKES TUESDAY NIGHT/WEDNESDAY MORNING LOOKS TO BE BE SHORT LIVED AS THE MORE SIGNIFICANT UPPER LOW MOVES INTO THE UPPER MISSISSIPPI VALLEY ON WEDNESDAY (PER EUROPEAN/GFS/CANADIAN). OF COURSE...THIS IS NOT A DONE DEAL JUST YET....AS IT IS NOT OUT OF THE REALM OF POSSIBILITY THE NORTHERN STREAM SHORTWAVE TROUGH BYPASSES THE SYSTEM...WITH MUCH OF THE ENERGY LINGERING BACK ACROSS THE CENTRAL/SOUTHERN PLAINS. WITH THIS UNCERTAINTY...TIMING REMAINS PROBLEMATIC...BUT IT DOES LOOK LIKE WEDNESDAY WILL REMAIN DRY...AS MOISTURE IS NOT EXPECTED TO INCREASE IN EARNEST UNTIL VERY LATE IN THE DAY OR WEDNESDAY NIGHT. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...SMALL CRAFT ADVISORY...NEARSHORE WATERS FROM PORT AUSTIN TO PORT HURON INCLUDING SAGINAW BAY UNTIL 6 AM SUNDAY. LAKE ST CLAIR...SMALL CRAFT ADVISORY...UNTIL 6 PM SATURDAY. MI WATERS OF LAKE ERIE...SMALL CRAFT ADVISORY...UNTIL 6 AM SUNDAY. && $$ SHORT TERM/AVIATION...CONSIDINE LONG TERM...SF mi AREA FORECAST DISCUSSION...CORRECTED NATIONAL WEATHER SERVICE ALBUQUERQUE NM 311 PM MDT SAT OCT 8 2005 CORRECTED DAY OF THE WEEK IN SECOND PARAGRAPH. .DISCUSSION... CONSIDERABLE CHANGE IN THE WEATHER AS A TROUGH MOVES CLOSER AND CLOSER TO THE LAND OF ENCHANTMENT. RUC80 ANALYSIS INDICATING AN UPPER LEVEL SHORT WAVE IS TRACKING THROUGH ERN AZ/WRN NM WITHIN EXIT REGION OF TROUGH. THIS WAVE HAS INITIATED SCATTERED SHOWERS AND STORMS OVER THE WRN ZONES AS VERTICAL ASCENT INCREASES IN AN AREA OF 300MB DIVERGENCE. SEVERE WEATHER COULD BE A THREAT THIS AFTERNOON/EVENING AS STEEP LAPSE RATES COMBINED WITH DEEP LAYER SHEAR ALLOW A FEW STORMS TO PRODUCE STRONG GUSTY WINDS AND LARGE HAIL. ACTIVITY WILL WORK EASTWARD THIS EVENING WITH SCATTERED TO NUMEROUS POPS ACROSS THE CENTRAL AND WRN ZONES. VERY LIGHT SNOW SHOWERS ARE POSSIBLE ACROSS THE SRN SAN JUAN MOUNTAINS ALONG THE CO BORDER. BEST THREAT WILL MAINLY OCCUR OVER THE HIGHEST PEAKS AND ACCUMULATIONS WILL BE INSIGNIFICANT. MODELS CONTINUE TO BE IN GOOD AGREEMENT WITH THIS SYSTEM THROUGH SUNDAY...BUT DIFFER SLIGHTLY ON THE EJECTION SPEED AND HOW WRAP AROUND PCPN AFFECTS THE REGION. GFS IS SLIGHTLY FASTER...HOWEVER WILL USE A BLEND OF THE GFS AND NAM AS CLOSED LOWS ARE TYPICALLY SLOW TO MOVE WITHOUT A KICKER. SIGNIFICANT SERIES OF VORT MAXES WILL SPIN AROUND THE UPPER LOW ACROSS THE CWFA...THUS SCATTERED/ NUMEROUS POPS A GOOD CALL FOR SUN. HIGHEST VALUES SHOULD BE OVER THE NRN/NE ZONES. SNOW SHOWERS ARE STILL EXPECTED ACROSS THE MTS OF NRN/W CNTRL NM SUN NIGHT. ACCUMULATIONS ARE POSSIBLE OVER THE NRN MOUNTAINS...GENERALLY ABOVE 8500 FEET. DO NOT EXPECT WARNING CRITERIA TO OCCUR ATTM...HOWEVER A FEW AREAS ALONG THE CO BORDER COULD EXPERIENCE SOME ADVISORY SNOWFALL IF TEMPS CAN REMAIN COOL ENOUGH. TO COMPLICATE MATTERS...A SURFACE COLD FRONT WILL SLIDE SOUTHWARD ALONG THE FRONT RANGE OF THE ROCKY MOUNTAINS AND BRING LOW LEVEL MOISTURE TO THE NE CORNER OF THE STATE. LATE SUN NIGHT/ EARLY MON MAY PROVE A BIT TRICKY FOR THE RATON PASS. A NORTHERLY UPSLOPE FLOW SHOULD KEEP THE HEAVIEST SNOWFALL ON THE CO SIDE OF THE PASS. GFS STARTS TO PULL OUT THE UPPER LOW ON MON AS A DRY SLOT STARTS TO WORK INTO AZ/SW NM. INCREASED POP GRIDS ACROSS THE BOARD BY A FACTOR OF TEN PERCENT BANKING ON A SLOWER EJECTION. LATER SHIFTS WILL NEED TO MONITOR TIMING MORE CLOSELY WITH FUTURE MODEL RUNS. NONETHELESS...WRAP AROUND PCPN WILL BEGIN TO AFFECT THE NRN CWFA FOR MON/MONDAY NIGHT. SNOW LEVELS WILL DROP FOR THE EVENING AS A COOLER POCKET OF MID-LEVEL AIR WORKS INTO THE STATE. TEMPERATURES WERE LOWERED THROUGHOUT THE SHORT TERM PERIODS AS A THICK CLOUD COVER AND COLD AIR MASS ALOFT AFFECTS THE REGION. IN ADDITION...A SURFACE FRONT WILL PUSH INTO THE NE CORNER OF NM AND CLEAR THE ERN PLAINS THROUGHOUT MONDAY. WILL HOLD OFF ON AN EAST CANYON WIND AT THIS TIME...BUT SOMETHING TO WATCH. LOW GRADE POPS LINGER IN THE FORECAST FOR TUE/WED AS UPPER LEVEL NW FLOW LINGERS AND A FEW EMBEDDED SHORT WAVES SET OFF ISOLATED SHOWERS. DPORTER && .PRELIMINARY POINT TEMPS/POPS... FARMINGTON...................... 49 63 42 61 / 60 50 30 20 GALLUP.......................... 44 63 36 60 / 50 40 20 20 GRANTS.......................... 45 62 37 59 / 60 50 30 20 GLENWOOD........................ 51 72 42 70 / 50 40 20 10 CHAMA........................... 37 52 30 51 / 70 70 50 50 LOS ALAMOS...................... 43 58 36 54 / 60 60 40 40 RED RIVER....................... 36 49 27 42 / 40 60 50 60 TAOS............................ 45 60 38 52 / 50 50 50 50 SANTA FE........................ 46 58 37 54 / 50 50 40 40 SANTA FE AIRPORT................ 48 60 40 56 / 50 50 30 40 ESPANOLA........................ 47 63 40 58 / 60 60 40 40 ALBUQUERQUE HEIGHTS............. 53 66 47 63 / 50 50 30 30 ALBUQUERQUE VALLEY.............. 50 67 47 65 / 50 50 30 30 ALBUQUERQUE FOOTHILLS........... 50 65 43 63 / 50 50 30 30 ALBUQUERQUE WEST MESA........... 51 68 44 65 / 50 50 30 30 SOCORRO......................... 52 72 47 67 / 50 50 30 20 SANDIA PARK/CEDAR CREST......... 44 61 37 56 / 50 50 30 30 MORIARTY/ESTANCIA............... 47 63 41 58 / 40 50 30 30 CARRIZOZO....................... 51 70 46 65 / 40 50 30 20 RUIDOSO......................... 48 62 40 58 / 30 50 30 20 RATON........................... 44 67 38 51 / 20 40 60 60 LAS VEGAS....................... 46 62 37 55 / 40 40 40 40 ROY............................. 48 67 41 54 / 20 40 50 50 CLAYTON......................... 50 71 44 54 / 20 30 60 50 SANTA ROSA...................... 51 71 45 64 / 20 40 40 30 TUCUMCARI....................... 54 74 51 64 / 20 30 50 40 FORT SUMNER..................... 53 75 49 66 / 20 30 40 30 CLOVIS.......................... 52 75 49 65 / 10 30 50 20 PORTALES........................ 52 76 50 68 / 10 30 50 20 ROSWELL......................... 54 79 53 73 / 20 30 40 10 && .ABQ WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 46 nm AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE ALBUQUERQUE NM 311 PM MDT SAT OCT 8 2005 .DISCUSSION... CONSIDERABLE CHANGE IN THE WEATHER AS A TROUGH MOVES CLOSER AND CLOSER TO THE LAND OF ENCHANTMENT. RUC80 ANALYSIS INDICATING AN UPPER LEVEL SHORT WAVE IS TRACKING THROUGH ERN AZ/WRN NM WITHIN EXIT REGION OF TROUGH. THIS WAVE HAS INITIATED SCATTERED SHOWERS AND STORMS OVER THE WRN ZONES AS VERTICAL ASCENT INCREASES IN AN AREA OF 300MB DIVERGENCE. SEVERE WEATHER COULD BE A THREAT THIS AFTERNOON/EVENING AS STEEP LAPSE RATES COMBINED WITH DEEP LAYER SHEAR ALLOW A FEW STORMS TO PRODUCE STRONG GUSTY WINDS AND LARGE HAIL. ACTIVITY WILL WORK EASTWARD THIS EVENING WITH SCATTERED TO NUMEROUS POPS ACROSS THE CENTRAL AND WRN ZONES. VERY LIGHT SNOW SHOWERS ARE POSSIBLE ACROSS THE SRN SAN JUAN MOUNTAINS ALONG THE CO BORDER. BEST THREAT WILL MAINLY OCCUR OVER THE HIGHEST PEAKS AND ACCUMULATIONS WILL BE INSIGNIFICANT. MODELS CONTINUE TO BE IN GOOD AGREEMENT WITH THIS SYSTEM THROUGH SUNDAY...BUT DIFFER SLIGHTLY ON THE EJECTION SPEED AND HOW WRAP AROUND PCPN AFFECTS THE REGION. GFS IS SLIGHTLY FASTER...HOWEVER WILL USE A BLEND OF THE GFS AND NAM AS CLOSED LOWS ARE TYPICALLY SLOW TO MOVE WITHOUT A KICKER. SIGNIFICANT SERIES OF VORT MAXES WILL SPIN AROUND THE UPPER LOW ACROSS THE CWFA...THUS SCATTERED/ NUMEROUS POPS A GOOD CALL FOR SUN. HIGHEST VALUES SHOULD BE OVER THE NRN/NE ZONES. SNOW SHOWERS ARE STILL EXPECTED ACROSS THE MTS OF NRN/W CNTRL NM WED NIGHT. ACCUMULATIONS ARE POSSIBLE OVER THE NRN MOUNTAINS...GENERALLY ABOVE 8500 FEET. DO NOT EXPECT WARNING CRITERIA TO OCCUR ATTM...HOWEVER A FEW AREAS ALONG THE CO BORDER COULD EXPERIENCE SOME ADVISORY SNOWFALL IF TEMPS CAN REMAIN COOL ENOUGH. TO COMPLICATE MATTERS...A SURFACE COLD FRONT WILL SLIDE SOUTHWARD ALONG THE FRONT RANGE OF THE ROCKY MOUNTAINS AND BRING LOW LEVEL MOISTURE TO THE NE CORNER OF THE STATE. LATE SUN NIGHT/ EARLY MON MAY PROVE A BIT TRICKY FOR THE RATON PASS. A NORTHERLY UPSLOPE FLOW SHOULD KEEP THE HEAVIEST SNOWFALL ON THE CO SIDE OF THE PASS. GFS STARTS TO PULL OUT THE UPPER LOW ON MON AS A DRY SLOT STARTS TO WORK INTO AZ/SW NM. INCREASED POP GRIDS ACROSS THE BOARD BY A FACTOR OF TEN PERCENT BANKING ON A SLOWER EJECTION. LATER SHIFTS WILL NEED TO MONITOR TIMING MORE CLOSELY WITH FUTURE MODEL RUNS. NONETHELESS...WRAP AROUND PCPN WILL BEGIN TO AFFECT THE NRN CWFA FOR MON/MONDAY NIGHT. SNOW LEVELS WILL DROP FOR THE EVENING AS A COOLER POCKET OF MID-LEVEL AIR WORKS INTO THE STATE. TEMPERATURES WERE LOWERED THROUGHOUT THE SHORT TERM PERIODS AS A THICK CLOUD COVER AND COLD AIR MASS ALOFT AFFECTS THE REGION. IN ADDITION...A SURFACE FRONT WILL PUSH INTO THE NE CORNER OF NM AND CLEAR THE ERN PLAINS THROUGHOUT MONDAY. WILL HOLD OFF ON AN EAST CANYON WIND AT THIS TIME...BUT SOMETHING TO WATCH. LOW GRADE POPS LINGER IN THE FORECAST FOR TUE/WED AS UPPER LEVEL NW FLOW LINGERS AND A FEW EMBEDDED SHORT WAVES SET OFF ISOLATED SHOWERS. DPORTER && .PRELIMINARY POINT TEMPS/POPS... FARMINGTON...................... 49 63 42 61 / 60 50 30 20 GALLUP.......................... 44 63 36 60 / 50 40 20 20 GRANTS.......................... 45 62 37 59 / 60 50 30 20 GLENWOOD........................ 51 72 42 70 / 50 40 20 10 CHAMA........................... 37 52 30 51 / 70 70 50 50 LOS ALAMOS...................... 43 58 36 54 / 60 60 40 40 RED RIVER....................... 36 49 27 42 / 40 60 50 60 TAOS............................ 45 60 38 52 / 50 50 50 50 SANTA FE........................ 46 58 37 54 / 50 50 40 40 SANTA FE AIRPORT................ 48 60 40 56 / 50 50 30 40 ESPANOLA........................ 47 63 40 58 / 60 60 40 40 ALBUQUERQUE HEIGHTS............. 53 66 47 63 / 50 50 30 30 ALBUQUERQUE VALLEY.............. 50 67 47 65 / 50 50 30 30 ALBUQUERQUE FOOTHILLS........... 50 65 43 63 / 50 50 30 30 ALBUQUERQUE WEST MESA........... 51 68 44 65 / 50 50 30 30 SOCORRO......................... 52 72 47 67 / 50 50 30 20 SANDIA PARK/CEDAR CREST......... 44 61 37 56 / 50 50 30 30 MORIARTY/ESTANCIA............... 47 63 41 58 / 40 50 30 30 CARRIZOZO....................... 51 70 46 65 / 40 50 30 20 RUIDOSO......................... 48 62 40 58 / 30 50 30 20 RATON........................... 44 67 38 51 / 20 40 60 60 LAS VEGAS....................... 46 62 37 55 / 40 40 40 40 ROY............................. 48 67 41 54 / 20 40 50 50 CLAYTON......................... 50 71 44 54 / 20 30 60 50 SANTA ROSA...................... 51 71 45 64 / 20 40 40 30 TUCUMCARI....................... 54 74 51 64 / 20 30 50 40 FORT SUMNER..................... 53 75 49 66 / 20 30 40 30 CLOVIS.......................... 52 75 49 65 / 10 30 50 20 PORTALES........................ 52 76 50 68 / 10 30 50 20 ROSWELL......................... 54 79 53 73 / 20 30 40 10 && .ABQ WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 46 nm AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC 1246 PM EDT SAT OCT 8 2005 .SHORT TERM (REST OF TODAY)... UPDATING TO RAISE MAXIMUM TEMPERTAURES LEE OF MTS AND ALONG BLUE RIDGE WHERE LACK OF CLOUDS HAS ALLOWED TEMPERATURES TO CLIMB. && .PREVIOUS DISCUSSION... (ISSUED 1009 AM EDT SAT OCT 8 2005) SHORT TERM (REST OF TODAY)... COMPLEX UPPER PATTERN WITH CLOSED LOW IN MI...CUTOFF LOW IN OK...AND TROUGH IN GA/FL. SURFACE COLD FRONT STRETCHES NE TO SW BETWEEN FOOTHILLS AND PIEDMONT...AS EVIDENCED BY DEW POINT GRADIENT THERE. SATELLITE IMAGERY SHOWS SIGNIFICANT BREAK IN EXTENSIVE CLOUD COVER LEE OF MTS...WHERE DOWNSLOPE FLOW NOTED IN OBSEVATIONS. LOWERED SKY COVER PER SATELLITE IMAGERY. ALSO LOWERED POPS... ESPECIALLY IMMEDIATE LEE OF MOUNTAINS WHERE BEST DRYING OCCURRING. ADDED THUNDER EXTREME E WHERE MODEL CAPES REMAIN MARGINAL. DICOUNTED MODEL CAPES UPPER SAVANNAH VALLEY WHERE MODEL DEW POINTS REMAIN HIGHER THAN OBSERVED VALUES. RAISED MAX TEMPERATURES IN FOOTHILLS WHERE OBSERVATIONS ABOVE GUIDANCE...AND LOWERED TEMPERATURES IN MOUNTAINS WHERE OBSERVATIONS BELOW GUIDANCE. UPDATED DEW POINTS WITH OBSERVED VALUES THIS MORNING...HIGHER E AND LOWER W. ADJUSTED MAV TOO MOIST MID MORNING...AND ADJUSTED MET EVEN MORE MOIST...SO JUST REDUCED OBSERVED MORING DEW POINT BY A DEGREE OR SO. BY MID DAY ADJUSTED MAV ON TRACK WITH STEADY DRYING THROUGH AFTERNOON. UPDATED WIND FROM RUC WHHICH MAINTAINS WEAK DOWNSLOPE THROUGH DAY. PREVIOUS DISCUSSION... (ISSUED 548 AM EDT SAT OCT 8 2005) SHORT TERM (REST OF TODAY)... WILL UPDATE PUBLIC PRODUCTS AND GRIDS TO ALLOW WATCH TO EXPIRE AND TO LOWER POPS ACROSS THE FORMER WATCH AREA. WILL ALSO MAKE A FEW ADJUSTMENTS TO HIGH MOUNTAIN MAX TEMPS FOR TODAY GIVEN WARM START. PREVIOUS DISCUSSION... (ISSUED 307 AM EDT SAT OCT 8 2005) SHORT TERM (TODAY THROUGH MONDAY)... SFC LOW CENTER ANALYZED JUST WEST OF CHARLOTTE AT 06Z THIS MORNING...WITH RADAR SHOWING RAPIDLY DIMINISHING PRECIP COVERAGE ACROSS THE REGION. WILL CANCEL THE CURRENT FFA FOR SW SECTIONS THAT EXPERIENCED NO FLOODING FRIDAY...AND ALLOW REMAINDER OF FOOTHILL AND PIEDMONT LOCATIONS TO EXPIRE ON SCHEDULE AT 6 AM. THE GFS SOLUTION WILL BE HEAVILY PREFERRED THROUGH THE PERIOD...WITH BETTER MID LEVEL DRYING AS BOUNDARY VERY SLOWLY SLIDES EAST AND NE GULF UPPER VORT TRANSLATES UP THE ERN SEABOARD. MODELS AGREE FAIRLY WELL WITH THE NRN STREAM GREAT LAKES WAVE STAYING N OF THE REGION...WHILE THE LOWER MS VALLEY WAVE OPENS UP AND BRUSHES THE NC MTNS ON MONDAY. IN THE INTERIM...LOW LEVELS SHOULD REMAIN FAIRLY MOIST...AND A WEAK 850 MB LOW IS EXPECTED TO REDEVELOP SOMEWHERE WEST OF THE REGION TO BRING LIGHT UPGLIDE BACK IN THROUGH THE WEEKEND. WITH THE DEEPER MOISTURE DIMINISHING... HOWEVER...MEASURABLE RAINFALL SHOULD NOT BE ESPECIALLY WIDESPREAD BUT DRIZZLE AND LOW CLOUDS COULD REMAIN PERSISTENT. WILL ACCORDINGLY KEEP A FAIRLY SMALL DIURNAL RANGE ON TEMPS. SHOWER CHANCE MAY INCREASE SLIGHTLY ACROSS THE MTNS LATE SUN NIGHT AND MON AS VORT LIFTS OUT. LONG TERM (MONDAY NIGHT THROUGH FRIDAY)... THE DEEPER CLOSED LOW IN THE PLAIN SHOULD GRADUALLY OPEN UP AND LIFT NE TOWARD THE GREAT LAKES BY LATE WEEK. LIMITED PRECIP CHANCES UNDER WEAK SE RIDGING UNTIL LATE WEEK LOOKS VERY GOOD STILL AND NO CHANGES EXPECTED. AVIATION... STRONG DEEP LAYER FORCING IS GRADUALLY SHIFTING TO THE NORTH...WITH THREAT FOR RAINFALL AT TERMINALS RAPIDLY ENDING. THEREFORE...THE MAIN CONCERN FOR THE REMAINDER OF THE MORNING WILL BE THE FOG/ STRATUS POTENTIAL. KGSP VAD WIND PROFILE INDICATES NORTHERLY FLOW IN THE LOWEST 6K FEET OR SO. CIGS AT THE UPSTATE TERMINALS AND KAVL HAVE LIFTED TO MVFR/VFR IN THE PAST FEW HOURS...AND IN CONSIDERATION OF THIS WEAK DOWNSLOPE COMPONENT...WOULD EXPECT THEM TO STAY THERE FOR FOR THE REMAINDER OF THE MORNING. WILL JUST INDICATE FEW-SCT CLOUDS IN THE IFR RANGE. AT KCLT...WHICH SHOULD REMAIN EAST OF THE H8 TROUGH FOR THE REMAINDER OF THE MORNING...WILL CONTINUE AT LEAST TEMPOS FOR IFR. WITH EXTENSIVE CLOUD COVER AND WEAK MIXING (ESP ACROSS THE WEST)...DO NOT EXPECT VISBY TO BE A BIG PROBLEM THIS MORNING...AND WITH ALL 4 TERMINALS ALREADY WELL INTO THE VFR RANGE...WILL LIMIT VISBY RESTRICTIONS TO THE UPPER END OF MVFR. && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SHORT TERM...JAT sc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MORRISTOWN TN 305 PM EDT SAT OCT 8 2005 .SHORT TERM... TONIGHT THROUGH SATURDAY...THE RAIN HAS ENDED ACROSS THE FORECAST AREA THIS AFTERNOON WITH A FEW AREAS OF DRIZZLE STILL POSSIBLE. LOW CLOUDS STILL BLANKET ALMOST ALL OF THE AREA WITH SOME BREAKS ACROSS SW NC AND ACROSS THE SOUTHERN VALLEY. THE COLD FRONT HAS NOW MOVED ALMOST TO THE EAST COAST AT MID AFTERNOON. COLD AIR ADVECTION IS CONTINUING WITH STRONGEST WINDS NEAR 15 MPH OVER THE SOUTHERN VALLEY. TEMPERATURES ARE STILL COOL AND RANGE FROM THE MID 50S IN PARTS OF SW VA AND THE NORTHERN CUMBERLAND PLATEAU TO THE LOWER AND MID 60S EXCEPT THE UPPER 60S SOUTHERN VALLEY AND LOWER 70S SW NC. CURRENT SATELLITE PICTURES AND SHORT TERM RUC MODEL SHOWING UPPER LOW OVER OHIO BRINGING SOME LOW CLOUDS SOUTH TOWARD THE OHIO RIVER. ANOTHER MID LEVEL LOW NOW OVER THE ARKLATEX IS ALREADY SPREADING HIGH AND MID LEVEL CLOUDS NE INTO MIDDLE TN AND NORTH AL ABOVE THE LOW CLOUD DECK THAT IS STILL THERE THIS AFTERNOON. THIS UPPER LOW WILL MOVE NORTHEAST INTO WEST TN BY SUNDAY AFTERNOON. FOR TONIGHT AND SUNDAY THE MAIN PROBLEM WILL BE LINGERING LOW LEVEL MOISTURE AND ITS AFFECT ON LOW AND HIGH TEMPERATURES. THE GFS MODEL IS SCOURING OUT THE MOISTURE SOME TONIGHT AND SUNDAY AND THE GUIDANCE DROPS TEMPERATURES INTO THE UPPER 40S...THEN SUNDAY WITH BREAKS WARMING MOST PLACES INTO THE 70S. WILL FOLLOW THE WARMER NAM NUMBERS TONIGHT IN THE LOWER 50S AND FOR SUNDAY A BLEND WITH TEMPERATURES A FEW DEGREES BELOW MAV. CROSS SECTION RH DATA BELOW 850 MB STAYS ABOVE 90 PERCENT THROUGH SUNDAY ACROSS THE FORECAST AREA. .LONG TERM... SUNDAY NIGHT THROUGH TUESDAY...THE MIDLEVEL LOW WILL LIFT NORTHEAST AND CROSS THE AREA SUNDAY NIGHT THROUGH MONDAY. IN RESPONSE THE 850 MB WINDS TURN TO A MORE UPSLOPE COMPONENT AND INCREASE. LOW LEVEL WARM THETA-E ADVECTION WILL BE OCCURRING BELOW 500 MB COOLING...RESULTING IN 850-500 LAPSE RATES OF 6 TO 7 C/KM. NAM ALSO SHOWS SLIGHTLY NEGATIVE LI ON MONDAY ALONG WITH SURFACE CONVERGENCE IN THE TN VALLEY WITH DEWPOINTS IN THE LOWER/MID 60S. THUS WILL ADD A MENTION OF ISOLATED THUNDER. WV IMAGERY INDICATES THAT DEEP MOISTURE IS LIMITED WITH THIS SYSTEM...AND THE GFS SHOWS VERY LITTLE LIFT DESPITE A 28/S VORT MAX...SO WILL KEEP POPS AT A LOW CHANCE. HEIGHTS RISE ON MONDAY NIGHT AND TUESDAY AS THE SYSTEM EXITS AND A SHORTWAVE RIDGE BUILDS OVERHEAD. TEMPS SUNDAY NIGHT WILL LEAN TOWARD THE WARMER MET GUIDANCE...IN THE MID/UPPER 50S. SOUTHWEST SECTIONS MAY SEE ENOUGH SUN MONDAY TO REACH 80 WHILE CLOUDS CENTRAL AND NORTHEAST WILL HOLD TEMPS IN THE 70S. WITH MORE SUNSHINE ON TUESDAY HIGHS SHOULD REACH THE MID 70S TO LOWER 80S. TUESDAY NIGHT THROUGH SATURDAY...MID LEVEL RIDGE AXIS WILL BE OVER THE AREA ON TUESDAY NIGHT...AND SHIFT TO THE EAST ON WEDNESDAY. THE RESULTING SOUTHWEST FLOW WILL INCREASE MOISTURE...AND AN APPROACHING UPPER TROUGH WILL INCREASE LIFT ON THURSDAY. MODELS DIFFER WITH THE STRENGTH AND TIMING OF THIS SYSTEM...WITH THE DGEX SHOWING A SLOW CLOSED CIRCULATION AND THE GFS SHOWING A PROGRESSIVE POSITIVELY-TILTED TROUGH. GIVEN THESE DISPARITIES WILL NOT MAKE SIGNIFICANT CHANGES AND POPS THURSDAY AND FRIDAY WILL BE KEPT AS LOW CHANCES. BEHIND THIS TROUGH A LARGE RIDGE CROSSES THE EASTERN CONUS...GIVING DRY WEATHER FOR THE WEEKEND. && .PRELIMINARY POINT TEMPS/POPS... CHATTANOOGA AIRPORT, TN 53 72 59 79 / 10 10 30 20 KNOXVILLE MCGHEE TYSON AIRPORT, TN 53 70 58 76 / 10 10 30 20 OAK RIDGE, TN 52 70 57 75 / 10 10 30 20 TRI CITIES AIRPORT, TN 50 69 55 71 / 10 10 20 30 && .MRX WATCHES/WARNINGS/ADVISORIES... NC...NONE. TN...NONE. VA...NONE. && $$ TD/DGS tn