AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE PUEBLO CO 358 AM MST WED JAN 28 2004 .SHORT TERM... (TODAY AND TONIGHT) FORECAST CHALLENGE TODAY/TONIGHT ARE PRIMARILY TEMPS... LATEST OBSERVATIONS SHOWING COLD FRONT ACROSS NORTHEAST CO AND KS FROM ROUGHLY AN AKO...TO SOUTH OF GLD...TO GBD LINE AT 10Z. MSAS 3HR PRESSURE CHANGE CHARTS ARE STILL SHOWING WEAKENING PRESSURE RISES (2MB)SHIFTING SLOWLY SOUTHWARD THROUGH WESTERN KANSAS. ALREADY...00Z AND EVEN 06Z MEOS-ETA NOT VERIFYING WELL WITH CURRENT FRONTAL POSITION (MESO-ETA HAS FRONT LOCATED TOO FAR NORTH). RUC 40 HAS MUCH BETTER HANDLE ON FRONT...AND WILL BASE FORECAST PRIMARILY OFF OF THIS. SO...MAIN CHALLENGE IS HOW FAR WEST WITH FRONT BACK-DOOR INTO SE COLORADO THIS AFTERNOON. BY 18Z RUC40 HAS LIGHT EASTERLY SFC WINDS EXTENDING ALL THEY WAY UP TO KPUB. ALTHOUGH AXIS OF MAIN PRESSURE RISES WILL LIKELY STAY WELL EAST OF THE AREA...EVEN DIURNAL SHIFT IN WINDS TO AN EASTERLY DIRECTION WILL ALSO HELP TO ADVECT IN COOLER TEMPS WESTWARD TO AROUND PUB. AND FOR ICING ON THE CAKE...MOST OF SOUTHEAST COLORADO IS STILL COVERED IN SNOW...WITH EXCEPTION OF KIOWA AND BACA COUNTIES (SOME MELTING OCCURRED YESTERDAY ACROSS BACA YESTERDAY). WITH ALL THAT SAID..THINK THAT LOWER ARKANSAS RIVER VALLEY MAY NOT WARM MUCH OUT OF THE 30S THIS AFTERNOON...AND HAVE BROUGHT TEMPERATURE GRADIENT WESTWARD IN CURRENT GRIDS. (GOING AROUND 10 DEGREES BELOW GUIDANCE...HOWEVER THIS FEELS JUSTIFIABLE AS RUC KEEPS 850MB TEMPS AT KLAA AT -2.5C EVEN AT 21Z). NOT MUCH MOISTURE WITH THIS SURGE...AND TO FIND ANY LOW CLOUDS ONE MUST LOOK ALL THE WAY TO NRN NE...THUS HAVE REMOVED FLURRIES. ACROSS REMAINDER OF FCST AREA...NORTHWEST FLOW STILL DOMINATES WITH UPPER LOW ACROSS SRN CA/NV MOVING INTO NRN OLD MEXICO AND THE SRN TIPS OF AZ/NM BY 12Z THURS. THIS KEEPS QG ASCENT WELL WEST AND SOUTH OF FCST AREA. STILL ENOUGH RESIDUAL MOISTURE IN NORTHWEST FLOW TO JUSTIFY SOME ISOLATED TO SCATTERED MTN POPS (HIGHEST POPS FOR SAWATCH RANGE WHERE BETTER OROGRAPHICS WILL BE). OVERNIGHT...MESO-ETA (WHICH ISN'T HANDLING LOW LVL COLD AIR VERY WELL TO BEGIN WITH)...SHIFT SFC HIGH IN CENTRAL PLAINS EASTWARD WITH TIME...AND LOW LVL WINDS BECOME WESTERLY AS COLD AIR DRAINS OUT OF ARKANSAS RIVER VALLEY. THINK THIS MAY BE TOO SOON...AND EVEN IF IT DOES...WITH SNOW COVER STILL ON THE GROUND...BELOW GUIDANCE MIN TEMPS STILL LOOKS GOOD. ALONG THE LOWER EAST FACING SLOPES OF SANGRES/WETS/PIKES PEAK/RAMPART RANGE...ENHANCED DRAINAGE WINDS SHOULD CONTIUE...KEEPING MIN TEMPS WARMER. ETA BUFR SOUNDING SHOW ANOTHER MTN TOP INVERSION SETS UP FOR A WEAK MTN WAVE EVENT. MTN TOP WINDS ARE ONLY AROUND 25-30 KTS...SO WIND GUSTS SHOULD BE WELL BELOW HIGH WIND CRITERIA...BUT ENOUGH TO FEEL AN AFFECT ON MIN TEMPS... KEEPING READINGS IN THE 20S FOR MOST OF THE NIGHT. -KT .LONG TERM... (THURSDAY NIGHT THROUGH TUESDAY). ...UNCERTAINTY CONTINUES AS SHALLOW COLD SURGES CONTINUE TO OUR EAST WHILE EXTENDED LOOKS SOMEWHAT UNSETTLED... THERE ARE MANY CONCERNS THIS PERIOD AS WEATHER IS EXPECTED TO BE QUITE UNSETTLED...ESPECIALLY INTO THE WEEKEND INTO NEXT WEEK. COLD SHALLOW POOLS TO OUR EAST WILL ALSO PRESENT FCST CONCERN AS MODELS HAVE PROBLEMS WITH EXTENT OF HOW FAR COOL AIR WILL MAKE IT BACK WEST. THE BEST WAY TO DISCUSS THESE CONCERNS IS TO SIMPLY GO "DAY BY DAY" IN THIS DISCUSSION. THURSDAY...NORTHWEST FLOW WILL DOMINATE ALOFT. MODELS IN AGREEMENT IN BRINGING ANOTHER SURGE DOWN THE PLAINS DURING THIS DAY...BUT HOW FAR WEST THIS SURGE MAKES IS NOT WELL KNOWN. BY 00 FRI HAS THE SURGE ON THE CO. DURING THE AFTERNOON THURSDAY...ALL GUIDANCE WANTS TO KEEP GENERALLY WESTERLY FLOW AT LOWER LEVELS. BASED ON THIS...I DECIDED TO KEEP I-25 CORRIDOR ON THE WARM SIDE (50S) WHILE IN THE FAR EAST...MAXES ARE FCST TO REACH ONLY ~40F. AS FOR POPS...KEPT SLIGHT CHANCE OF PRECIP IN C AND SW MTNS. THU NIGHT...MODELS WANT TO FORCE COLDER AIR IN KS EAST DURING NIGHT. I DO NOT BELIEVE IT AND KEEP MINS QUITE COLD FOR THU MORNING... ESPECIALLY OUT ON THE BORDER. AS FOR CLOUDS...I KEPT IN PC FOR NOW BUT LATER SHIFTS MAY HAVE TO ADD SOME LOW STRATUS IN FOR THIS TIME PERIOD FRIDAY...FLOW ALOFT TRANSISTIONS FROM NW TO SW. WITH W FLOW PREVAILING AT ALL LEVELS...THIS SHOULD BE THE WARMEST DAY ACROSS THE REGION. HOWEVER I AM STILL CONCERNED THAT TEMPS MAY NOT WARM UP ON FAR E PLAINS AND KEPT THIS AREA IN THE MID 40S FOR MAXES. FRI NIGHT...SHOULD BE A WARM NIGHT ALONG I-25 CORRIDOR AS DOWNSLOPE WILL PREVAIL IN LLVLS. TEMPS SHOULD BE IN THE UPPER 20S TO LOWER 30S. OUT EAST TEMPS ALSO ON THE RISE...BUT KEPT MINS IN THE 20S. THINGS WILL START TO GET GOING IN THE MTNS AS TROUGH ALOFT BEGINS TO MOVE OVER AREA. POPS PUSHED INTO THE LIKELY CATEGORY. WINDS AND DYNAMICS LOOK GOOD BUT LAPSE RATES DON'T EXCITE ME MUCH. FOR THIS REASON KEPT PRECIP ON THE SHOWERY SIDE (VS STEADY SNOW). SATURDAY...STRONG PAC FRONT WITH COLD AIR WILL MOVE ACROSS REGION ON THIS DAY. EXPECT GUSTY WINDS ALL AREAS WITH CHANCE OF SNOW ALL AREAS. BEST CHANCE OF COURSE WILL CONTINUE OVER HIGHER TERRAIN. TEMPS COOL DOWN ALL AREAS WITH HIGHS IN THE 40S PLAINS...20S/30S MTNS. FROM THIS POINT ON...THINGS GET MORE INTERESTING BUT MORE UNCERTAIN. "TREND" IN GUIDANCE IS TO BRING MAIN JET OVER OR JUST SOUTH OF COLORADO THROUGH THE LATE WEEKEND INTO NEXT WEEK. THIS WILL KEEP US IN THE COLDER AIR WITH A GOOD CHANCE OF PRECIP ALL AREAS INTO MONDAY. GFS AND EC HINT AT UPSLOPE ACROSS FAR S MTNS SUNDAY...AND HAVE KEPT BEST CHANCE OF POPS THIS AREA. TEMPS SUNDAY QUITE COOL WITH HIGHS ONLY IN THE 20S PLAINS. FOR MONDAY...EUROPEAN GUIDANCE INDICATED POTENTIAL FOR CONTINUED PRECIP...AND DECIDED TO KEEP SLIGHT CHANCE GOING ALL AREAS. TUESDAY THINGS FCST TO DRY OUT. \/HODANISH. && .PUB WATCHES/WARNINGS/ADVISORIES...NONE. && $$ co AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MELBOURNE FL 910 PM EST WED JAN 28 2004 ...COLD OVERNIGHT WITH FREEZING TEMPERATURES ACROSS LAKE AND INTERIOR VOLUSIA COUNTIES... .DISCUSSION... AS ANTICIPATED...WITH SUCH A DRY LOW LEVEL AIR MASS IN PLACE...TEMPS HAVE BEEN DROPPING OFF QUICKLY AFTER SUNSET. IN FACT...AS OF 02Z... PIERSON (NW VOLUSIA) WAS ALREADY DOWN TO 34F...UMATILLA 39F. AIRPORT SITES GENERALLY RUNNING M-U40S...MOSTLY L40S AT THE MORE RURAL SITES (FAWN SITES/KMXR TOWER NETWORK). DEW PTS HAVE JUMPED A GOOD 15F FROM LATE AFTN MINS IN THE U10S AND L20S DUE TO DECOUPLING OF SFC/BLYR AIR MASSES. LIGHT SFC DRAINAGE FLOW BECOMING ESTABLISHED AREA-WIDE ATTM. ANIMATED W/V AND IR IMAGERY SHOWS VERY LITTLE CI OVHD...AND NO REAL INCREASING TREND IMMEDIATELY UPSTREAM AND IS MAINLY CONFINED TO WRN /CTRL GULF COAST (LF QUAD OF 130KT+ TX/MX JTSRK) AND ACROSS THE SERN GOMEX-FL STRAITS/SOUTH FL (RR QUAD OF DEPARTING 150-170KT JTSRK). FCST...CALM TO LIGHT N-NW WINDS SHOULD ALLOW TEMPS TO CONTINUE A SLOW FALL THROUGH SUNUP...SO FROM A WIND STANDPOINT...RADIATIONAL COOLING CONDS WILL BE GOOD BUT NOT IDEAL. MAIN FCST ISSUE IS OBVIOUSLY FCST MIN TEMPS. ADDRESSING WHETHER THERE WILL BE SOME MITIGATION OF THE TEMP FALL DUE TO THICKER/EXPANSIVE HIGH CLOUD DEVELOPMENT...WHILE SHORT RANGE GUIDANCE SHOWS INCREASING RH/DIVG IN THE H30-H20 LAYER OVERNIGHT... SATELLITE AND RUC ANLYS FIELDS INDICATE SKC TO NO MORE THAN THIN SCT CI WILL CONTINUE MOST OF THE NIGHT. 18Z MAV MINS HAVE COME UP 1-2F MOST LOCALES...AND WITH CURRENT MINS ALREADY A COUPLE DEGS BELOW 12Z GUIDANCE...PLAN TO TWEAK MINS UP A DEGREE OR TWO...AND MAKE SOME MINOR ADJSTMENTS TO HRLY FIELDS BASED UPON CURRENT OBS. && .MARINE...CURRENT OBS SHOW 16P22KT/8FT @41010 AND 15P22KT/5FT @41009 WHICH INDICATES ~15KT AND 4-6FT...BUT STILL PROBABLY AROUND 7FT IN THE GULF STREAM. HOWEVER...LATEST GUIDANCE...INCLUDING THE HIGH RES 12KM ETA FROM 18Z...INDICATES RAPID FALL TO <15KT SUSTAINED BY 06Z AND 10KT OR LESS BY SUNRISE. HENCE...WE WILL START OFF WITH SCEC WINDS/SEAS...DIMINISHING BELOW CAUTIONARY LEVELS AFTER MIDNIGHT. && .MLB WATCHES/WARNINGS/ADVISORIES... FREEZE WARNING TONIGHT FOR LAKE AND INTERIOR VOLUSIA COUNTIES. && $$ SHORT TERM...CRISTALDI LONG TERM...HIRSCH fl AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BOISE IDAHO 915 AM MST WED JAN 28 2004 .DISCUSSION...UPDATES FORTHCOMING AROUND 945 AM. LIGHT SNOW HAS BEGUN IN THE BOISE MOUNTAINS WITH MCCALL AT 31F AND BRUNDAGE PICKING UP AN INCH ON THE /STICK/ CAM. SNOTEL SITES IN ADAMS AND VALLEY COUNTY IDAHO AND IN BAKER COUNTY ALSO INDICATE A FEW SITES WITH AN INCH THIS MORNING. THIS WHILE SATELLITE AND RUC INDICATES NO PRECIP ELSEWHERE AS OF 9 AM. FREEZING FOG IS BEING REPORTED IN ONTARIO AND BAKER CITY WHILE MOST VALLEY TEMPERATURES FELL ONLY SLIGHTLY /1-4F/ OR WERE STEADY IN THE UPPER 20S AND LOWER 30S OVERNIGHT. RAOB/ACARS INDICATE A 130KT SPEED MAX NEAR 47N 125-130W AT 12-14Z WHICH SHIFTS OVER THE WEST CENTRAL MOUNTAINS AROUND 21Z AS THE VERY MOIST PLUME OF PACIFIC MOISTURE CONTINUES TO SINK SLOWLY S. THIS ALONG WITH THE EARLIER START IN THE CENTRAL MTS WILL BRING 3-6 INCHES BY 6PM THERE. THIS FEATURE INDUCES SNOWFALL IN BAKER COUNTY OF 1 TO 4 INCHES ABOVE 3800 FT THOUGH SHOULD BEGIN AS SNOW OR FREEZING RAIN IN BAKER BY 10 AM THEN CHANGE TO ALL RAIN. SNOW LEVELS WILL BE RISING FROM VALLEY FLOORS TO AROUND 4500 FEET THIS AFTERNOON. 12Z RUNS ALL INDICATE SPOTS OF A QUARTER INCH/6 HRS THIS AFTERNOON IN THE CENTRAL MTS. WINDS WILL MIX OUT THE SOUTHERN VALLEYS THIS AFTERNOON WITH HIGHS 35-45 SOUTH WITH THE N MOUNTAINS IN THE 30S. WILL TWEAK UP THE WINDS IN UPPER TREASURE VALLEY. HEAVY SNOW WARNING TIMING SLIGHTLY LATER IN BOISE MTS BUT NO CHGS PLANNED EXCEPT TWEAKING SNOWFALL IN ZONES. .PREVIOUS DISCUSSION....315 AM MST WED JAN 28 2004 SHORT TERM...A VERY MOIST AND MILDER PATTERN SETTING UP OVER THE FORECAST AREA. A LONG FETCH OF PACIFIC MOISTURE IS POISED TO MOVE INTO THE FORECAST AREA LATER TODAY AND ESPECIALLY TONIGHT AND THURSDAY. UNLIKE THE PAST FEW SYSTEMS, MILDER AIR IS SPREADING NORTHWARD IN A STRONG PATTERN OF WARM ADVECTION. THUS, HEAVY SNOW LIKELY TO BE CONFINED TO THE NORTHERN MOUNTAINS ABOVE 4500 FEET WHILE LOWER ELEVATIONS THIS TIME GET A MIXTURE OF RAIN/SNOW AT FIRST THEN ALL RAIN LATER. WINTER STORM WATCHES HAVE BEEN POSTED ALREADY FOR THE WEST CENTRAL AND BOISE MOUNTAINS AND THESE TO BE UPGRADED WITH THE ISSUANCE OF TODAY'S EARLY MORNING PACKAGE TO HEAVY SNOW WARNINGS. REALLY HARD TO SAY EXACTLY HOW MUCH SNOW WILL FALL IN THESE AREAS OVER THE NEXT TWO TO THREE DAYS BUT WOULD NOT BE SURPRISED TO SEE MORE THAN 2 FEET IN NORTHERN VALLEY COUNTY AND A FOOT OR MORE IN THE BOISE MOUNTAINS. THIS WARM ADVECTION PATTERN EXPECTED TO LAST UNTIL AT LEAST FRIDAY WITH SNAKE RIVER VALLEY HIGH TEMPS RISING INTO THE MID 40S AND LOWS NOT GOING BELOW THE MID 30S. WARMING TEMPS THAT WE HAVE NOT REALIZED IN A FEW WEEKS. FLOW EXPECTED TO BUCKLE ON FRIDAY AHEAD OF A VIGOROUS PACIFIC SHORT WAVE. MODELS INDICATE THAT A STRONG COLD FRONTAL PASSAGE WILL TAKE PLACE FRIDAY AFTERNOON ENDING THE LONG DURATION SNOW IN THE MOUNTAINS AND CHANGING TO AREAL EXTENT TO SCATTERED VALLEY RAIN AND MOUNTAIN SNOW SHOWERS. COLDER AIR THEN RETURNS IN THE POST FRONTAL AIR MASS WHICH SETS UP FOR A COLDER BUT SLIGHTLY DRIER WEEKEND. LONG TERM...FRIDAY NIGHT THROUGH WEDNESDAY. SHORT WAVE ON FRIDAY BRINGS A BIT COOLER AND DRIER AIR TO THE FORECAST AREA FOR SATURDAY AND SUNDAY...BUT THERE IS STILL QUITE A BIT OF MOISTURE IN THE NORTHWEST FLOW WITH THE BEST CHANCE OF PRECIPITATION ACROSS NORTHERN ZONES. MODELS DIVERGE FOR MONDAY AND TUESDAY FROM 24 HOURS AGO AS THE FLOW SPLITS OVER THE WESTERN U.S. WITH CWFA IN THE MIDDLE OF THE SPLIT. LATEST TREND IS TO MOVE A CUTOFF LOW OVER THE FORECAST AREA BUT THIS LOW WEAKENS AS IT MOVES ONSHORE AND WITH THE SPLIT FLOW DO NOT THINK MUCH WILL HAPPEN AS IS TRIES TO MOVE INTO THE RIDGE. WILL KEEP SOME SMALL POPS OVER THE FORECAST AREA BUT NOT MUCH MORE THAN CHANCE. FOR THE REST OF THE EXTENDED WILL BROAD BUSH POPS AS THERE IS TIMING DIFFERENCES WITH THE SHORTWAVE MOVING OVER THE AREA AND BEING THAT FAR OUT DO NOT WANT KEEP CHANGING THE FORECAST WITH THE CHANGE IN THE MODEL. && .BOI WATCHES/WARNINGS/ADVISORIES... .ID...HEAVY SNOW WARNING 11 13 NOON TODAY TIL 6PM THURS. .OR...NONE. $$ DISCUSSION...VM PREVIOUS... SHORT TERM...GS LONG TERM....JA id AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LINCOLN IL 1145 AM CST WED JAN 28 2004 .DISCUSSION... UPDATED THE FORECAST THIS AFTERNOON FOR MOSTLY CLOUDY SKIES NORTH OF I-70 AND CONTINUED PARTLY SUNNY FROM I-70 SOUTH. HIGHS TO RANGE FROM THE UPPER TEENS FROM I-74 NORTH TO THE MID 20S SOUTH OF I-70. NOT AS WINDY AS YESTERDAY WITH WEST WINDS 5 TO 15 MPH. 1037 MB ARCTIC HIGH PRESSURE OVER EASTERN SASKATCHEWAN AND RIDGING SOUTH ACROSS THE EASTERN PLAINS STATES INTO THE LOWER MISSISSIPPI VALLEY. ONE OF THE COLDEST MORNINGS OF THE SEASON WITH FRESH BLANKET OF SNOW. LOWS AROUND ZERO WITH SPRINGFIELD 3 BELOW AND HAVANA 4 BELOW WHILE SINGLE DIGITS OVER SE IL. 11 AM TEMPS RANGE FROM 8 IN PEORIA AND DECATUR...TO 18 IN LAWRENCEVILLE. MOLINE STILL 6 WHILE MACOMB JUST 7. A FEW AREAS FROM I-74 NORTH HAVE WIND CHILLS AROUND 5 BELOW. BATCH OF MID LEVEL CLOUDS RACED ESE ACROSS CENTRAL IL WHILE SOUTHERN IL STAYED SUNNY. MODELS SHOW ARCTIC RIDGE SHIFTING EAST TOWARD IL THROUGH TONIGHT KEEPING COLD TEMPS AROUND BUT WINDS NOT TOO STRONG. RUC AND MESOETA SHOW HIGHS NEAR 15 NW BY GALESUBURG TO 25 SE AT LAWRCEVILLE WHERE MORE SUNSHINE POSSIBLE AND NOT AS COLD TO BEGIN WITH. WEAK UPPER LEVEL DISTURBANCES IN NW UPPER LEVEL FLOW TO TRACK QUICKLY ESE ACROSS CENTRAL AND NORTHERN IL THROUGH THU WITH MORE CLOUD COVER THE FURTHER NORTH YOU GO. ETA TRENDING FURTHER SOUTH TOWARD GFS SOLUTION WITH A DISTURBANCE DURING THE DAY THU AND NOW LOOKS LIKE LIGHT SNOW BECOMES LIKELY FROM I-74 NORTH LATE THU MORNING AND THU AFTERNOON WITH 1 TO 2 INCHES OF SNOW POSSIBLE. .PREV DISCUSSION... SURFACE HIGH PRESSURE EXTENDS FROM THE NORTHERN PLAINS TO THE LOWER MISSISSIPPI RIVER VALLEY. A VIGOROUS NORTHERN STREAM SHORTWAVE WILL BRING A COLD FRONT...WITH A REINFORCING SHOT OF COLD AIR...INTO ILLINOIS LATE THIS AFTERNOON AND THIS EVENING. THIS WILL DO LITTLE TO ALLOW TEMPS TO WARM TODAY. COOLER GUIDANCE TEMPS ARE THE WAY TO GO...ESPECIALLY GIVEN COOLER THAN EXPECTED START TO THE DAY. MODELS ARE ALL IN GOOD AGREEMENT THROUGH THE FORECAST PERIOD...WITH THE MAIN CHALLENGE INVOLVED WITH PRECIPITATION CHANCES WITH ONE WAVE THURSDAY/THURSDAY NIGHT...AND ANOTHER SYSTEM OVER THE WEEKEND. SHORT TERM...TODAY THROUGH THURSDAY NIGHT... GUIDANCE TEMPS ARE TRENDING COLDER OVER THE REMAINDER OF THE WORK WEEK AND THIS TREND LOOKS REASONABLE GIVEN PERSISTANT NORTHERN STREAM SHORTWAVE ENERGY PROVIDING LITTLE BREAK IN THE UPPER LEVEL TROFING OVER THE GREAT LAKES/MID-MISSISSIPPI RIVER VALLEY. ALSO...SNOW COVER ON GROUND. FIRST WAVE PASSES WELL NORTH OF ILX CWA...BUT DOES ALONG A COLD FRONT TO MOVE THROUGH LATE TODAY/TONIGHT. DON/T EXPECT MORE THAN A SLIGHT CHANCE OF PCPN WITH THIS...WITH BETTER CHANCES COMING THURSDAY/THURSDAY NIGHT WITH A WAVE EXPECTED TO MOVE A BIT FARTHER SOUTH. MODELS ARE IN GOOD AGREEMENT WITH THE TIMING OF THIS FEATURE. NO SURPRISE THAT THE GFS IS MORE AGGRESSIVE WITH THE AREAL COVERAGE OF THE QPF...WILL LEAN TOWARD THE ETA...WITH THE BEST CHANCES ACROSS NORTHERN HALF OF ILLINOIS. IN EITHER CASE...30 POPS STILL LOOK WARRENTED. WITH LACK OF RETURN MOISTURE...THIS SYSTEM IS GOING TO HAVE TO USE WHAT IT BRING WITH IT. WAVE AND QPF CHANCES END BY FRIDAY MORNING. LONG TERM...FRIDAY THROUGH TUESDAY.... WILL SEE A BREAK ON PRECIPITATION CHANCES ON FRIDAY...THEN GFS SUGGESTS A MORE PROGRESSIVE UPPER LEVEL PATTERN...WITH UPPER LEVEL RIDGING BUILDING EASTWARD AND ALLOWING HEIGHTS...AND TEMPS...TO RISE BY SATURDAY. MRF STILL SUGGESTS NEXT SYSTEM TO MOVE INTO THE MIDWEST LATER SATURDAY. LOOKS AT THIS TIME THAT ILLINOIS WILL GET SPLIT...WITH NORTHERN STREAM ENERGY PASSING TO THE NORTHWEST AND SOUTHERN STREAM ENERGY DEVELOPING TO THE SOUTH...WITH LOWER POPS BETWEEN. WILL NEED TO CLOSELY MONITOR SOUTHERN STREAM TRENDS...AS LATEST EXTENDED GFS SUGGESTS THIS MIGHT KEEP A MORE EXTENDED PERIOD OF PRECIPITATION ON THE SOUTHERN END OF THE FRONT INTO EARLY NEXT WEEK. HOWEVER...FOR NOW SEE LITTLE REASON TO MAKE BIG CHANGES TO GOING EXTENDED FORECAST. && .ILX WATCHES/WARNINGS/ADVISORIES... IL...NONE. && $$ PLAHMER/HUETTL il AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GOODLAND KS 1218 PM MST WED JAN 28 2004 .DISCUSSION...UPDATED VARIOUS 1ST PERIOD PARAMETERS AS FORECAST CHALLENGE IS THE TEMPERATURES. AT 19Z TEMPERATURES RANGED FROM 47 DEGREES IN FLAGLER TO 3 DEGREES IN THE NORTHEAST CORNER OF NORTON COUNTY. LATEST RUC PICKED UP WELL ON ABOUT HALF OF THE FORECAST AREA WHILE THE ETA DID BETTER OVER THE WEST. SHORT TERM FORECASTER AND MYSELF ATTEMPTED TO USE THE ETA OVER THE WEST AND RUC OVER THE EAST USING THE SERP TOOL FOR THE INDIVIDUAL COUNTIES WITH WEATHER OBSERVATIONS AND USED THE INTERPOLATE BETWEEN CURRENT OBS AND EXPECTED HIGHS AROUND 21Z. TRICKY PART WILL BE HOW MUCH WARMER IT GETS FROM WEST TO EAST. COULD SEE ANOTHER UPDATE IF TEMPERATURES WARM MORE THAN EXPECTED...ESPECIALLY OVER THE WEST. LATEST RUC IS TRYING TO CATCH UP WITH THE 25 DEGREE GRADIENT ACROSS KIT CARSON COUNTY BUT TIME OF MAX HEATING IS BEGINNING TO RUN OUT. ONLY OTHER UPDATE WAS FOR THE WINDS...DEWPOINTS...AND LOWER CLOUD COVER A BIT. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ DDT ks AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 940 PM EST WED JAN 28 2004 .DISCUSSION... MAIN FCST CONCERNS OVERNIGHT ARE LES TRENDS...LOW TEMPS AND WIND CHILLS. WV IMAGERY SHOWS MIDLEVEL TROF EXTENDING FROM NRN SASKATCHEWAN TO LAKE SUPERIOR TO THE S OF HIGH LATITUDE RIDGING FROM SRN GREENLAND TO HUDSON BAY. DEEP COLD AIR ASSOCIATED WITH TROF IS SUPPORTING MDT/HVY LES OFF LAKE SUPERIOR IN GENERAL WNW FLOW THIS EVENING. BASED ON C-MAN OBS...LOW-LEVEL CONVERGENCE IS BEING MAXIMIZED FROM ONTONAGON COUNTY N TO ABOUT KCMX. IR IMAGERY SUPPORTS THIS WITH MOST PERSISTENT COLDEST CLOUD TOPS SIMILARLY LOCATED. TO THE E...UNUSUAL TO SEE LES STRUCTURE BASICALLY CONSISTING OF JUST A COUPLE OF DOMINANT BANDS INSTEAD OF NUMEROUS WIND PARALLEL BANDS. SATELLITE AND KMQT RADAR IMAGERY SHOW ONE CYCLONICALLY CURVED INTENSE DOMINANT BAND EXTENDING FROM NEAR PILM4 TO JUST OFF THE TIP OF THE KEWEENAW AND THEN TO NRN LUCE COUNTY. ANOTHER SIGNIFICANT BUT WEAKER BAND EXTENDS FROM JUST N OF THE HURON ISLANDS TO PICTURED ROCKS. INLAND...CLEAR SKIES ARE THE RULE FROM INLAND GOGEBIC COUNTY TO MARQUETTE/WRN ALGER AND SRN SCHOOLCRAFT. OTHER THAN KIWD/KIMT...WIND CHILL READINGS HAVE STAYED ABOVE ADVY CRITERIA SO FAR THIS EVENING. GOING FCST IS IN GOOD SHAPE...BUT SOME HEADLINE CHANGES WILL BE MADE. ETA/RUC SHOW LOW-LEVEL CONVERGENCE REMAINING STRONGEST ACROSS ONTONAGON AND SRN HALF OF HOUGHTON COUNTY OVERNIGHT. THIS LOOKS ON TRACK AS LAND BREEZE COMPONENT OFF FRIGID MN/NW WI RESULTS IN A W/WSWRLY WIND AT S END OF WRN LAKE SUPERIOR. EXPECT BEST SNOW ACCUMULATIONS (ADDITIONAL 3-5 OVERNIGHT) FROM AROUND ROCKLAND TO PAINESDALE OUT W. BASED ON SATELLITE/RADAR...NOT MUCH LES HAS BEEN REACHING BARAGA COUNTY...AND IT ACTUALLY LOOKS AS THOUGH A GOOD PART OF THE COUNTY HAS MOSTLY CLEAR SKIES BASED ON STEADILY FALLING IR TEMPS...INDICATING COOLING SFC TEMPS UNDER CLR SKIES. LOW-LEVEL CONVERGENCE IS TO BECOME FOCUSED JUST UPWIND OF BARAGA COUNTY DURING THE NIGHT...WHICH SHOULD RESULT IN MORE LES REACHING MORE OF THE COUNTY. HOWEVER...ACCUMULATIONS WILL NOT BE GREAT GIVEN COLD AIR MASS (LIMITED SNOW GROWTH)...SOMEWHAT DRIER AIR ADVECTING INTO THE AREA AND WELL INLAND LOCATION. PLUS...BLSN IS PROBABLY NOT MUCH OF AN ISSUE BEING SHELTERED FROM INSTABILITY OVER LAKE SUPERIOR. WILL THUS CANCEL ADVY FOR BARAGA COUNTY. LOCALLY AN ADDITIONAL INCH OR TWO THERE AND LITTLE IN THE WAY OF BLSN. WILL ISSUE WIND CHILL ADVY THOUGH AS TEMPS DROP TO -5 TO -10F...RESULTING IN WIND CHILLS AROUND -25F WITH AT LEAST 10 MPH WIND. ACROSS NCNTRL...MAX SNOW WILL BE FOCUSED FROM JUST E OF MUNISING TO TAHQUAMENON FALLS PER LOW-LEVEL CONVERGENCE FIELDS FROM ETA/RUC. GOING FCST HAS THIS HANDLED WELL. WOULDN'T BE SURPRISED TO SEE AN ADDITIONAL 6-7 INCHES LOCALLY DURING THE NIGHT IF THE ONE DOMINANT BAND MAINTAINS ITSELF AND SHIFTS LITTLE. ACROSS THE REST OF FCST AREA...MAINLY CLR SKIES WILL ALLOW TEMPS TO PLUMMET. WILL BE DROPPING LOW END OF MINS TO -10 TO -15F FROM MARQUETTE COUNTY TO DELTA/MENOMINEE AND CLOSE TO -20F OVER INTERIOR SW. WILL NEED TO DROP SRN SCHOOLCRAFT DOWN TO -5 TO -10F AS SKIES LIKELY TO REMAIN CLR THERE. WITH LOWER TEMPS...WILL ALSO INCLUDE DELTA/SRN SCHOOLCRAFT IN WIND CHILL ADVY OVERNIGHT/THU MORNING. && .PREV DISCUSSION... DISCUSSION ISSUED AT 515 PM EST FOR THU-WED... THURS-THURS NIGHT...UPR LOW SLIDES EAST OF THE WRN GRTLKS WITH CHILLY NW FLOW ALOFT IN ITS WAKE. ARCTIC AIR IN PLACE WILL MAINTAIN LAKE INDUCED SNOW SHOWERS AND SQUALLS DOWNWIND OF LAKE SUPERIOR. INCREASING DRYING AND LOWERING OF SUBSIDENCE INVERSION TO AROUND 3K FEET BY THURS EVENING WILL GRADUALLY WEAKEN THE INTENSITY OF THE LES BANDS HOWEVER DESPITE SLOWLY MODERATING LOW LVL TEMPS THERMAL INSTABILITY REMAINS VERY SUFFICIENT TO KEEP SNOW SHOWERS CONTINUING OVERNIGHT. FRI-FRI NIGHT...BROAD CYCLONIC FLOW ALOFT CONTINUES AS DEEP UPR TROF/CUT OFF LOW OVR EASTERN NOAM WOBBLES ABOUT. SERIES OF UPR LVL VORT MAXES ROTATING AROUND THE PARENT LOW EVEN RETROGRADE THE LOW SOMEWHAT PER THE GFS/ETA FRI AFTN-EVNG. SFC-BOUNDARY LAYER FLOW FROM 300-310 DEGREES PERSISTS ACROSS UPR MI WHILE LOW LVL THERMAL INSTABILITY REMAINS WELL MORE THAN SUFFICIENT (H85 TEMPS FM -12 TO -14) KEEP LAKE INDUCED SNOWS GOING. WEAK VORT CAUGHT IN NW FLOW ALOFT AHEAD OF ADVANCING UPR RIDGE TRAVERSES UPR MI FRI NIGHT. THIS FEATURE MAY RAISE CAPPING INVERSION SLGTLY HWVR SYNOPTIC MOISTURE IS PRETTY SKIMPY HENCE EXPECT LAKE ENHANCED SNOWFALL TO REMAIN BLO ADVISORY CRITERIA FRI NIGHT. SAT...UPR RIDGING BUILDS EAST FROM THE PLAINS INTO THE WRN GRTLKS SAT WITH SFC PRES GRADIENT RELAXING AHEAD OF RIDGE AXIS. SOME MODEL DIFFERENCES IN THE TIMING OF THESE FEATURES WITH GFS FASTER, DEPICTING THE SFC RIDGE EAST OF THE U.P. BY 00Z SUN... AND THE ETA SOMEWHAT SLOWER SHOWING THE SFC RIDGE STILL OVR THE FAR WESTERN U.P. AT 00Z SUN. HAVE COMPROMISED SOMEWHAT BUT LEANED TOWARD THE FASTER GFS GIVEN ITS BETTER RUN TO RUN CONSISTENCY AND DECENT AGREEMENT ON CONVERGING TO A SOLUTION WITH THE UKMET/ECMWF. TIMING OF THE PASSAGE OF THE RIDGE AXIS KEY TO TURNING OFF THE LAKE EFFECT SNOW FROM WEST TO EAST ACROSS UPR MI SAT. SFC-BOUNDARY LAYER FLOW BECOMING S TO SE WILL PUSH BANDS OFFSHORE YIELDING A BRIEF (VERY BRIEF!) BREAK IN SNOWFALL IN THE NORTHWEST FLOW FAVORED SNOW BELTS OF LAKE SUPERIOR. SAT NIGHT-SUN...MEDIUM RANGE MODELS CONTINUE TO TREND TOWARD A SCENARIO CONSISTENT WITH A COMPROMISE BETWEEN THE FASTER GFS AND SOMEWHAT SLOWER ECMWF IN THE PROGRESSION OF THE UPR LVL RIDGE MOVG ACROSS THE WRN GRTLKS SAT AHEAD OF A UPR TROF/CLOSED LOW OVER THE NRN PLAINS. WITH SUFFICIENT UPR ENERGY TO SUPPORT A CLOSED LOW XPECT A SFC LOW TO ORGANIZE OVER THE PLAINS SAT PER OPERATIONAL GFS AND LIFT NE ACROSS WRN LK SUPERIOR SUN. MODEST ISENT LIFT IN THE WARM AIR ADVECTION PATTERN AHEAD OF THE LOW SHOULD SPREAD A SWATH OF LGT SNOW NORTHEASTWARD ACROSS THE U.P. LATE SAT NIGHT INTO SUN. MON-WED...A REINFORCING SHOT OF ARCTIC AIR SURGES SOUTHWARD IN THE WAKE OF THIS LOW INTO THE UPR GRTLKS SUN NIGHT INTO MON. SFC-BOUNDARY LAYER FLOW FROM 280-290 DEG BUILDS IN QUICKLY BEHIND THE COLD FRONTAL PASSAGE WITH STRONG 1030 MB SFC HI OVR IA. THIS TRAJECTORY WILL LIMIT LAKE INDUCED SNOW TO MAINLY JUST THE KEWEENAW AND IMMEDIATE SHORELINE AREAS EAST OF MUNISING SUN NIGHT-MON NIGHT DESPITE STRONG THERMAL INSTABILITY (H85 TEMPS LOWERING TO -20 BY 00Z TUES). CONSIDERABLE DISAGREEMENT REMAINS BTWN GFS/ECMWF/UKMET/CANADIAN MODELS IN HANDLING OF PAC ENERGY DIVING INTO THE CNTRL PLAINS. OPERATIONAL ECMWF IS MUCH SLOWER AND DEEPER AND THUS DVLPS A DEEP SFC LOW OVR THE MID MS VALLEY ON TUES. GFS AND UKMET SOMEWHAT WEAKER WITH UPPER SHRTWV WITH SOMEWHAT BETTER RUN TO RUN CONSISTENCY. && MQT WATCHES/WARNINGS/ADVISORIES... WINTER STORM WARNING OVERNIGHT MIZ002-003-084. WINTER STORM WARNING THROUGH THURSDAY MIZ006-007-085. LAKE EFFECT SNOW AND BLOWING SNOW ADVISORY OVERNIGHT MIZ001. WIND CHILL ADVY UNTIL 10 AM EST/9AM CST THU MIZ004-005-009>014. HEAVY FREEZING SPRAY WARNING IN EFFECT LAKE SUPERIOR. && $$ ROLFSON (DISCUSSION) ED F (PREV DISCUSSION) mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 515 PM EST WED JAN 28 2004 .SHORT TERM... MAIN FCST CONCERNS TONIGHT ARE LES TRENDS AND WIND CHILLS. WV IMAGERY AND RUC ANALYSIS INDICATED HIGH LATITUDE RDG FROM GREENLAND INTO NE CANADA AND A A MID LVL TROF FROM CNTRL CANADA TOWARD THE WRN LAKES. SHRTWV/VORT INTO CNTRL UPR MI REPRESENTED LEADING EDGE OF ARCTIC AIR INTRUSION INTO THE NRN LAKES. NEXT SIGNIFICANT UPSTREAM SHRTWV WAS LOCATED OVER SRN ALBERTA. AT THE SFC...GRADIENT WAS TIGHTENING WITH INCREASING NW WINDS BTWN RDG OF ARCTIC HI PRES FROM CNTRL CANADA INTO THE ERN PLAINS AND TROF FROM NRN NEW ENGLAND TOWARD LK SUPERIOR. RADAR AND VIS SATELLITE INDICATED MULTIPLE WIND PARALLEL BANDS ORIENTATION GRADUALLY SHIFTING WITH BACKING WINDS WITH TRANSITION FROM A FEW MORE DOMINANT CONV BANDS TO WEAKER LES LOCATIONS FROM ONTONAGON TO CMX AND KP59. OVER THE EAST...MAIN LES FOCUS HAD SHIFTED EAST OF MUNISING. SINCE THE ETA HAS HAS SHOWN REASONABLE DEPICTION OF LOW LVL WINDS AND ENHANCED CONV...WILL GENERALLY FOLLOW FOR WIND DETAILS. TONIGHT...H8 TEMPS FALLING INTO THE -23C TO NEAR -26 RANGE WILL BE LESS FAVORABLE FOR DECENT SNOW GROWTH WITH SHALLOW PRFL IN -15C TO -18C RANGE. DEPARTURE OF THE SHRTWV WITH DNVA/QDIV TAKING OVER AND WILL CONTINUE TO LEAD TO LESSER SNOWFALL RATES FROM W TO E. BEST 950 CONV REMAINED NEAR M-38 IN THE WEST AND FROM ERN ALGER INTO NRN LUCE COUNTIES IN THE EAST. ADJUSTED LCL GUIDANCE...WOULD STILL GIVE 2-5 INCH AMOUNTS OVER THE WEST AND 3 TO 7 INCHES OVER THE EAST...WITH LONGER FETCH. HOWEVER...FCST SNDGS STILL SUGGEST 2K-3K FT WINDS TO 30 KT THAT WITH ONGOING CAA...SHOULD MIX TOWARD THE SFC PRODUCING SIGNIFICANT BLOWING AND DRIFTING SNOW. OTHERWISE...INFLUX OF ARCTIC AIR WILL PUSH TEMPS INTO THE -5 TO -12 F RANGE INLAND OVERNIGHT. WHILE BNDRY LYR WINDS WILL BE ENOUGH TO LIMIT RADIATIONAL COOLING AND KEEP TEMPS FROM DROPPING TOWARD FRIGID UPSTREAM READINGS...WINDS REMAINING IN THE 10 TO 15 MPH RANGE BY MORNING WILL PRODUCE WIND CHILLS IN THE 15 TO 30 BELOW ZERO RANGE OVER INTERIOR PORTIONS OF WEST AND CNTRL UPR MI. SO...WIND CHILL ADVY ISSUED. JLB .LONG TERM... THURS-THURS NIGHT...UPR LOW SLIDES EAST OF THE WRN GRTLKS WITH CHILLY NW FLOW ALOFT IN ITS WAKE. ARCTIC AIR IN PLACE WILL MAINTAIN LAKE INDUCED SNOW SHOWERS AND SQUALLS DOWNWIND OF LAKE SUPERIOR. INCREASING DRYING AND LOWERING OF SUBSIDENCE INVERSION TO AROUND 3K FEET BY THURS EVENING WILL GRADUALLY WEAKEN THE INTENSITY OF THE LES BANDS HOWEVER DESPITE SLOWLY MODERATING LOW LVL TEMPS THERMAL INSTABILITY REMAINS VERY SUFFICIENT TO KEEP SNOW SHOWERS CONTINUING OVERNIGHT. FRI-FRI NIGHT...BROAD CYCLONIC FLOW ALOFT CONTINUES AS DEEP UPR TROF/CUT OFF LOW OVR EASTERN NOAM WOBBLES ABOUT. SERIES OF UPR LVL VORT MAXES ROTATING AROUND THE PARENT LOW EVEN RETROGRADE THE LOW SOMEWHAT PER THE GFS/ETA FRI AFTN-EVNG. SFC-BOUNDARY LAYER FLOW FROM 300-310 DEGREES PERSISTS ACROSS UPR MI WHILE LOW LVL THERMAL INSTABILITY REMAINS WELL MORE THAN SUFFICIENT (H85 TEMPS FM -12 TO -14) KEEP LAKE INDUCED SNOWS GOING. WEAK VORT CAUGHT IN NW FLOW ALOFT AHEAD OF ADVANCING UPR RIDGE TRAVERSES UPR MI FRI NIGHT. THIS FEATURE MAY RAISE CAPPING INVERSION SLGTLY HWVR SYNOPTIC MOISTURE IS PRETTY SKIMPY HENCE EXPECT LAKE ENHANCED SNOWFALL TO REMAIN BLO ADVISORY CRITERIA FRI NIGHT. SAT...UPR RIDGING BUILDS EAST FROM THE PLAINS INTO THE WRN GRTLKS SAT WITH SFC PRES GRADIENT RELAXING AHEAD OF RIDGE AXIS. SOME MODEL DIFFERENCES IN THE TIMING OF THESE FEATURES WITH GFS FASTER, DEPICTING THE SFC RIDGE EAST OF THE U.P. BY 00Z SUN... AND THE ETA SOMEWHAT SLOWER SHOWING THE SFC RIDGE STILL OVR THE FAR WESTERN U.P. AT 00Z SUN. HAVE COMPROMISED SOMEWHAT BUT LEANED TOWARD THE FASTER GFS GIVEN ITS BETTER RUN TO RUN CONSISTENCY AND DECENT AGREEMENT ON CONVERGING TO A SOLUTION WITH THE UKMET/ECMWF. TIMING OF THE PASSAGE OF THE RIDGE AXIS KEY TO TURNING OFF THE LAKE EFFECT SNOW FROM WEST TO EAST ACROSS UPR MI SAT. SFC-BOUNDARY LAYER FLOW BECOMING S TO SE WILL PUSH BANDS OFFSHORE YIELDING A BRIEF (VERY BRIEF!) BREAK IN SNOWFALL IN THE NORTHWEST FLOW FAVORED SNOW BELTS OF LAKE SUPERIOR. SAT NIGHT-SUN...MEDIUM RANGE MODELS CONTINUE TO TREND TOWARD A SCENARIO CONSISTENT WITH A COMPROMISE BETWEEN THE FASTER GFS AND SOMEWHAT SLOWER ECMWF IN THE PROGRESSION OF THE UPR LVL RIDGE MOVG ACROSS THE WRN GRTLKS SAT AHEAD OF A UPR TROF/CLOSED LOW OVER THE NRN PLAINS. WITH SUFFICIENT UPR ENERGY TO SUPPORT A CLOSED LOW XPECT A SFC LOW TO ORGANIZE OVER THE PLAINS SAT PER OPERATIONAL GFS AND LIFT NE ACROSS WRN LK SUPERIOR SUN. MODEST ISENT LIFT IN THE WARM AIR ADVECTION PATTERN AHEAD OF THE LOW SHOULD SPREAD A SWATH OF LGT SNOW NORTHEASTWARD ACROSS THE U.P. LATE SAT NIGHT INTO SUN. MON-WED...A REINFORCING SHOT OF ARCTIC AIR SURGES SOUTHWARD IN THE WAKE OF THIS LOW INTO THE UPR GRTLKS SUN NIGHT INTO MON. SFC-BOUNDARY LAYER FLOW FROM 280-290 DEG BUILDS IN QUICKLY BEHIND THE COLD FRONTAL PASSAGE WITH STRONG 1030 MB SFC HI OVR IA. THIS TRAJECTORY WILL LIMIT LAKE INDUCED SNOW TO MAINLY JUST THE KEWEENAW AND IMMEDIATE SHORELINE AREAS EAST OF MUNISING SUN NIGHT-MON NIGHT DESPITE STRONG THERMAL INSTABILITY (H85 TEMPS LOWERING TO -20 BY 00Z TUES). CONSIDERABLE DISAGREEMENT REMAINS BTWN GFS/ECMWF/UKMET/CANADIAN MODELS IN HANDLING OF PAC ENERGY DIVING INTO THE CNTRL PLAINS. OPERATIONAL ECMWF IS MUCH SLOWER AND DEEPER AND THUS DVLPS A DEEP SFC LOW OVR THE MID MS VALLEY ON TUES. GFS AND UKMET SOMEWHAT WEAKER WITH UPPER SHRTWV WITH SOMEWHAT BETTER RUN TO RUN CONSISTENCY. && MQT WATCHES/WARNINGS/ADVISORIES... WINTER STORM WARNING TONIGHT MIZ002-003-084. W INTER STORM WARNING THROUGH THURSDAY MIZ006-007-085. LAKE EFFECT SNOW AND BLOWING SNOW ADVISORY TONIGHT MIZ001-004. WIND CHILL ADVY TONIGHT AND EARLY THUR MIZ009. WIND CHILL ADVY MIDNIGHT TO 10 AM EST MIZ005-010-011-012 HEAVY FREEZING SPRAY WARNING IN EFFECT LAKE SUPERIOR. && $$ ED F mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 1150 AM EST WED JAN 28 2004 .DISCUSSION... MAIN FCST CONCERNS THIS AFTERNOON ARE LES TRENDS. WV IMAGERY AND RUC ANALYSIS INDICATED SHRTWV/VORT INTO WRN LK SUPERIOR. VIS SATELLITE AND RADAR LOOPS INDICATED TYPICAL MULTIPLE WIND PARALLEL BANDS WITH MAINLY 310 CBL FLOW. SHRTWV AND AREAS FAVORABLE 900-700 MB RH...PER 12Z KINL SNDG...HAS HELPED BOOST LES INTENSITY WITH SNOWFALL RATES OF 1-2 INCHES/HR OBSERVED NEAR ROCKLAND THIS MORNING. CONVERGENT FLOW OVER WRN LK SUPERIOR INTO NRN ONTONAGON COUNTY AND CNTRL HOUGHTON COUNTY WAS IN GOOD AGREEMENT WITH ETA 950 CONV FCSTS. ISLE ROYALE SHADOW WAS LIMITING INTENSITY OF BANDS INTO THE NRN KEWEENAW. OVER THE EAST BANDS WERE AFFECTING AREAS FROM DEERTON AND AU TRAIN EASTWARD. CAA WITH ARCTIC SURGE...PUSHING H8 TEMPS FROM -20C TO NEAR -25C WILL BE LESS FAVORABLE FOR DECENT SNOW GROWTH WITH SHALLOW PRFL IN -15C TO -18C RANGE. ONTONAGON COUNTY OBSERVERS HAVE ALREADY REPORTED TREND TOWARD SMALLER FINE SNOWFLAKES. DEPARTURE OF THE SHRTWV AND VERY DRY AIR UPSTREAM WILL LEAD TO LESSER SNOWFALL RATES FROM W TO E. OVER THE WEST...EXPECT FOCUS OF HEAVIER LES TO SHIFT SLIGHTLY NORTH TOWARD IN AREAS BTWN M-38 AND HOUGHTON. FCST SNDGS STILL SUGGEST 2K-3K FT WINDS TO 30 KT THAT WITH ONGOING CAA...SHOULD MIX TOWARD THE SFC PRODUCING SIGNIFICANT BLOWING AND DRIFTING SNOW. OVER THE EAST...SLIGHT BACKING FROM 320 TO 300 SHOULD SHIFT HEAVIER LES TO AREAS FROM MUNISING EASTWARD. WINDS...ESPECIALLY IN OPEN AREAS AND NEAR THE SHORELINE TO 30 MPH WILL ALSO CAUSE PROBLEMS WITH BLOWING AND DRIFTING SNOW. OTHERWISE...CAA AND INFLUX OF ARCTIC AIR WILL BRING STEADY OR SLOWLY FALLING TEMPS AS UPSTREAM READINGS OVER NE MN WERE AROUND -15F LATE THIS MORNING. WIND CHILLS IN THE 15 TO 25 BELOW ZERO RANGE EXPECTED OVER THE SW. SO...ONGOING HEADLINES UNCHANGED. && MQT WATCHES/WARNINGS/ADVISORIES... WINTER STORM WARNING THIS AFTERNOON AND TONIGHT MIZ002-003-084. WINTER STORM WARNING THIS AFTERNOON THROUGH THURSDAY MIZ006-007-085. LAKE EFFECT SNOW AND BLOWING SNOW ADVISORY THIS AFTERNOON AND TONIGHT MIZ001-004. HEAVY FREEZING SPRAY WARNING IN EFFECT LAKE SUPERIOR. && $$ JLB mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAND RAPIDS MI 1120 PM EST WED JAN 28 2004 .UPDATED... RADAR RETURNS AT 15Z SHOW THE SNOW SHOWERS ARE MOSTLY NEAR US-131 FROM MKG SOUTH...BUT NOT ALONG THE LAKE SHORE. THEY DO COVER THE LAKE SHORE AREAS NORTH OF MKG. THE SNOW SHOWERS NOT BEING NEAR THE LAKE SHORE SOUTH OF MKG IS DUE TO THE POCKET OF WARMER AND DRIER AIR OVER THE SRN 1/3 OF LAKE MICHIGAN (AS SEEN ON THE RUC AND ETA 00 HR FCST AT 12Z) THIS MORNING. OVER THAT AREA THE 850 MB AND 925 MB TEMPERATURES WERE NEAR -10C WITH A MEAN 1000/850 MB RH NEAR 50 PCT WHILE NORTH OF LDM -11C TO -12C WITH A MEAN 70+ PCT WERE NOTED (BOTH 925 MB AND 850 MB). THAT WARMER AND DRIER AIR WAS LIMITING THE LAKE EFFECT ACTIVITY NEAR THE LAKE SHORE EVEN THOUGH SFC TEMPERATURES WERE BELOW 10F FROM SBN TO CHI TO MKG AND GRB AT 15Z. HOWEVER THE ARCTIC FRONT IS COMING THROUGH THIS AFTERNOON AS SEEN WITH SOME MID CLOUDS OVER LAKE MICHIGAN AND THE STRONG SHORTWAVE ON THE NRN STREAM PASSING NORTH OF LOWER MICHIGAN THIS EVENING. AS THIS HAPPENS THE 70+ 1000/850 MB RH MOVES SOUTH WITH TIME OVER THE LAKE THIS AFTERNOON AND THE 925 MB TEMPERATURE FALLS TO NEAR -16C OVER THE SRN PART OF THE LAKE BY 00Z. THAT WILL ALLOW THE LAKE EFFECT TO DEVELOP FARTHER SOUTH WITH TIME (AFT 18Z) AND WITH A MORE WEST WIND THROUGH 850 MB TILL AFTER 00Z... THE LAKE EFFECT SNOW SHOWERS WILL CONTINUE TO REACH EAST OF US-131 THROUGH THE AFTERNOON. DUE TO THE LIMITED INVERSION HEIGHT... 1 TO 2 INCHES SHOULD DO IT FOR MOST AREAS THAT GET ACCUMULATIONS THIS AFTERNOON. SFC TEMPERATURES WILL PEAK AROUND 18Z THEN FALL AFTER THAT DUE TO THE ARCTIC AIR MOVING IN. THAT WILL INCREASE THE WIND SPEEDS AND RESULT IN INCREASED BLOWING AND DRIFTING SNOW NEAR AND WEST OF US-131. BOTTOM LINE IS NUMEROUS SNOW SHOWERS WITHIN 2 COUNTIES OF THE LAKE MICHIGAN SHORE WITH 1 TO 2 INCHES OF SNOW. SCATTERED SNOW SHOWERS INLAND WITH LITTLE IN THE WAY ACCUMULATION. STRONGER WINDS NEAR THE LAKE SHORE WILL RESULT IN BLOWING AND DRIFTING SNOW THERE. && .GRR...WATCHES/WARNINGS/ADVISORIES...NONE. $$ JK MEADE WDM mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 1031 AM EST WED JAN 28 2004 .UPDATE... REGIONAL RADARS SHOW LINGERING LIGHT SNOW CONTINUES TO DIMINISH BEHIND THE UPPER LOW NOW OVER PENNSYLVANIA/NEW YORK. SURFACE LOW OVER SOUTHEAST ONTARIO HAS FILLED...WITH LOW REDEVELOPING OFF THE EAST COAST. NEXT SHORTWAVE UPSTREAM MOVING INTO UPPER MICHIGAN...WITH AN ACCENTUATED SURFACE TROUGH ACROSS THE GREAT LAKES. SURFACE HIGH ACROSS CENTRAL CANADA WITH RIDGE BUILDING INTO THE NORTHERN PLAINS. THIS RESULTS IN A TIGHT PRESSURE GRADIENT ACROSS THE GREAT LAKES...WITH A NUMBER OF STATIONS IN SOUTHEAST MICHIGAN SUSTAINED 15 TO 20 MPH...WITH A FEW PEAK GUSTS NEAR 30 MPH. WITH THE GRADIENT EXPECTED TO TIGHTEN FURTHER THIS AFTERNOON...WILL KEEP BRISK WORDING THROUGH THE DAY. OTHERWISE SKIES REMAIN MOSTLY CLOUDY. ALREADY UPDATED TO INCREASE WINDS AND REMOVE PARTLY SUNNY MENTION FROM THIS MORNING. VIS/FOG IMAGERY SHOWS LOW CLOUD DECK EXPANDED ACROSS WISCONSIN JUST BEFORE SUNRISE...AND IS SPREADING EASTWARD ACROSS LAKE MICHIGAN. 12Z RUC LOOKED A LITTLE LEAN ON LOW-LEVEL MOISTURE COMPARED TO LATEST VISIBLE SATELLITE...BUT 12Z ETA A LITTLE BETTER. COMBINED WITH ADDITIONAL LIFT INDICATED BY INCREASING 850-500MB QVECTOR CONVERGENCE DURING THE AFTERNOON...WILL KEEP MENTION OF SCATTERED FLURRIES AND CLOUDS GOING THROUGH THE DAY. WHILE THERMAL RIDGE MOVES ACROSS THE STATE TODAY...WITH CLOUDS AND FRESH SNOW COVER DO NOT EXPECT TEMPERATURES TO WARM VERY MUCH THIS AFTERNOON. CURRENT MAX TEMP GRID IS ONLY A FEW DEGREES WARMER THAN CURRENT READINGS...WHICH STILL LOOKS REASONABLE. && BRAVENDER .PREV DISCUSSION...358 AM EST WED JAN 28 2004 THE WATER VAPOR LOOP SHOWS THE UPPER LOW RESPONSIBLE FOR YESTERDAYS STORM NOW OVER CENTRAL LAKE ERIE. WRAP AROUND MOISTURE AND MID LEVEL DEFORMATION HAS BEEN HANGING IN TOUGH OVER THE CENTRAL PORTION OF LOWER MICHIGAN OVERNIGHT. SATELLITE TRENDS SHOW THE CLOUD TOPS SLOWLY WARMING...WITH RADAR IMAGERY ALSO INDICATING A SLOW WEAKENING TREND. ANTICIPATE CURRENT AREA OF LIGHT SNOW/FLURRIES TO PUSH EAST AND EXIT THE FORECAST AREA OVER THE NEXT THREE TO SIX HOURS. ATTENTION THEN TURNS TO NEXT ROUND OF ARCTIC AIR ALREADY PUSHING INTO THE UPPER MIDWEST AND ITS INFLUENCE ON LAKE EFFECT SNOW ACROSS THE REGION. AS THE UPPER LOW MOVES OFF EAST TO THE ATLANTIC COAST TODAY...RIDGING ALOFT WILL BUILD INTO SOUTHEAST MICHIGAN. ANOTHER...MORE ELONGATED UPPER LOW ALREADY MOVING ACROSS NORTHERN MINNESOTA WILL PUSH INTO NORTHERN LOWER MICHIGAN THIS AFTERNOON. SOME ENHANCED FRONTOGENETICAL LIFT WILL OCCUR ALONG THE 850-700MB FRONTAL BOUNDARY DRAPED OVER THE MIDWEST/SOUTHERN LAKES REGION TO GENERATE SOME MID LEVEL CLOUDS...WHICH SHOULD ADVANCE ACROSS LOWER MICHIGAN DURING THE AFTERNOON. SHOULD SEE SOME BREAKS IN THE CLOUDS THIS MORNING ONCE THE MID LEVEL CLOUDS PUSH OFF TO THE EAST...ESPECIALLY ACROSS THE NORTHERN FORECAST AREA. 925MB TEMPS START DROPPING OFF DRASTICALLY OVER LAKE MICHIGAN THIS AFTERNOON. THUS DESPITE INVERSION HEIGHTS UNDER 3K FEET...WILL MAINTAIN A MENTION OF SCATTERED LAKE EFFECT FLURRIES UNDER A WESTERLY FLOW OFF LAKE MICHIGAN. MOISTURE DEEPENS OVER THE LAKE THIS AFTERNOON INTO THE EARLY PART OF THE EVENING AS A SURGE OF 850-700MB FRONTOGENETICAL LIFT PASSES OVER THE SOUTHERN PORTION OF THE LAKE. THIS LIFT ACTUALLY WORKS INTO THE DETROIT METRO AREA THIS EVENING. THE LIFT WILL BE WEAK AND BRIEF...BUT IN COMBINATION WITH THIS DEEPER MOISTURE AND SOME ENHANCEMENT OVER SOUTHERN LAKE MICHIGAN...WILL INTRODUCE A CHANCE OF SNOW SHOWERS ALONG/SOUTH OF M-59 THIS EVENING...WITH FLURRIES ACROSS THE REST OF THE FORECAST AREA. SOME MID LEVEL SUBSIDENCE WILL ADVANCE ACROSS THE REGION OVERNIGHT. 925MB TEMPS AROUND -18C OVER LAKE MICHIGAN AND BOUNDARY LAYER WINDS AROUND 20KT SHOULD ADVECT SOME LAKE CLOUDS AND FLURRIES INTO THE AREA OVERNIGHT...ESPECIALLY ACROSS THE SOUTH. THE NEXT SHORT WAVE WILL DROP INTO NORTHERN ILLINOIS BY THURSDAY EVENING. MODEL SOLUTIONS ARE FAIRLY SIMILAR WITH THIS FEATURE...WITH THE GFS ACTUALLY TRENDING WEAKER...AND MORE IN LINE WITH THE ETA. THINK THE ETA HAS THE BETTER HANDLE ON THE STRENGTH AND POSITION OF THE ARCTIC FRONT...SO WILL FAVOR ITS SOLUTION. THERE WILL QUITE A BIT OF FRONTOGENETICAL FORCING ALONG THE 850MB FRONT AS THIS WAVE MOVES INTO THE REGION. MOST OF THIS LIFT WILL BE FOCUSED ALONG AND SOUTH OF THE STATE LINE THOUGH. HOWEVER...DEEP MOISTURE DOES ADVANCE OVER SOUTHERN LAKE MICHIGAN DURING THE AFTERNOON. ENOUGH LIFT WILL PUSH INTO THE SOUTHERN PORTION OF THE LAKE TO RAISE INVERSION HEIGHTS TO NEAR 5K FT...PER ETA SOUNDINGS. THIS SHOULD BOOST LAKE EFFECT ACTIVITY DURING THE AFTERNOON. THE MESO ETA SOLUTION IS SHOWING A CONVERGENCE BAND DEVELOPING ALONG I-94...EXTENDING INTO THE DETROIT AREA BY THURSDAY EVENING. WILL THEREFORE CONTINUE TO MENTION SCATTERED POPS ACROSS THE SOUTH...AND ACTUALLY BRING CHANCE POPS NORTH TO I-69 IN THE EVENT THE MODELS ARE UNDERESTIMATING THE SOUTHWESTERLY COMPONENT TO THE WIND OVER NORTHERN IN/OH. THE TRENDS OVER THE LAST FEW DAYS IN THE MODELS HAVE BEEN FARTHER SOUTH WITH THE ARCTIC FRONTAL BOUNDARY. GIVEN THE WIDE AREA OF SUB ZERO AIR UPSTREAM AND WITH A VERY SOLID SNOWPACK IN PLACE ACROSS THE ENTIRE STATE...HAVE TAKEN TEMPERATURES DOWN SEVERAL DEGREES FROM PREVIOUS FORECASTS...AT THIS TIME LINING UP WELL WITH THE CURRENT MAV GUIDANCE. SUSPECT THAT ANY AMOUNT OF CLEARING OVERNIGHT OVER THE NEXT FEW DAYS WILL ONCE AGAIN SPELL SOME SUB ZERO LOW TEMPERATURES ACROSS THE AREA. && .DTX WATCHES/WARNINGS/ADVISORIES...NONE && $$ CONSIDINE EXPERIMENTAL GRAPHICAL FORECASTS ARE AVAILABLE ONLINE AT HTTP://WWW.CRH.NOAA.GOV/DTX (ALL LOWER CASE) mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 600 AM EST WED JAN 28 2004 .DISCUSSION... MAIN FCST CONCERNS ARE WSW HEADLINES FOR NW AND ERN COUNTIES INTO THU. WV IMAGERY AND RUC ANALYSIS SHOWS A CLIPPER SHRTWV OVER NRN MN TAKING AIM AT UPPER MICHIGAN. AT THE SFC...NEARLY STATIONARY 1001 MB LOW PRES REMAINS OVER THE THUMB WHILE AN INVERTED TROF EXTENDS FROM LOW INTO UPR MI AND FAR WRN ONTARIO. TROF IN ADVANCE OF 1040 MB RDG OVER SASKATCHEWAN WHICH IS BUILDING INTO ERN MT AND NRN PLAINS STATES. BITTER COLD ARCTIC AIR ASSOC WITH HIGH AS EARLY MORNING TEMPS HAVE DROPPED TO -40F OR LOWER ACROSS MUCH OF SASKATCHEWAN AND NRN ALBERTA. NW FLOW BETWEEN LOW TO EAST AND BUILDING ARCTIC HIGH SUSTAINING WIND PARALLEL LES BANDS OVER LAKE SUPERIOR. MQT RADAR SHOWS LES BANDS OVER ERN LAKE SUPERIOR SHIFTING EAST WITH SLIGHTLY BACKING CBL FLOW PER VWP...WRN EXTENT OF BEST BANDS NOW OVER FAR ERN MQT COUNTY. TODAY INTO THURSDAY...AS THE CLIPPER SHRTWV DIGS OVER UPR MI TODAY THE ARCTIC SFC HIGH WILL BUILD DEEPER INTO THE NRN PLAINS. THIS IN TURN WILL STRENGTHEN THE GRAD WIND ACROSS UPR MI AND SHIFT WINDS FROM NNW TO NW ACROSS LAKE SUPERIOR TODAY. BRIEF ENHANCEMENT FROM SHRTWV WILL ALLOW INVERSION HGTS TO RISE FROM 5 KFT TO AROUND 7KFT THIS AFT AND EVENING ACROSS LAKE SUPERIOR AS STRONG CAA LOWERS 850 MB TEMPS TO -23C TO -25C ACROSS LAKE SUPERIOR BY 00Z TONIGHT. 950 MB CONV STRENGTHENS OVER NW AND ERN COUNTIES IN NW CBL FLOW AS SHRTWV AND ASSOC ARCTIC FRONT/TROUGH MOVE THROUGH AREA. EXPECT INTENSE LES BANDS TO SET UP OVER THESE AREAS GIVEN INSTABILITY AND INITIAL FAVORABLE SNOW GROWTH ALONG AND JUST BEHIND FRONT AS NOTED ON ETA SNDGS. WINDS WITHIN THE MIXED LYR UP TO 30 KT OFF ETA SNDGS SO WOULD EXPECT GUSTS TO REACH UP TO 35 MPH ALONG SHORELINE AREAS WITH SUSTAINED WINDS OF 15 TO 30 MPH. THESE WINDS AND ALONG WITH HEAVY SNOW BANDS WILL PRODUCE OCCASIONAL WHITEOUT CONDITIONS THIS AFT INTO TONIGHT OVER HOUGHTON-ONT-BARAGA COUNTIES AS WELL AS ALGER-LUCE-NRN SCHOOLCRAFT COUNTIES. SNOWFLAKE GROWTH AND THUS LES ACCUMS WILL BECOME MORE LIMITED LATER TONIGHT FROM WEST AS VERY DRY...BITTER COLD AIR (-25C) CONTINUES TO POUR INTO REGION. ALTHOUGH SHORTER FETCH AND SNOW GROWTH LIMITATIONS MAY RESULT IN MARGINAL ACCUMS (6-10" TODAY AND TONIGHT) OVER MUCH OF WEST...HAVE STILL OPTED TO GO WITH WINTER STORM WARNINGS FOR HOUGHTON AND ONTONAGON COUNTIES GIVEN LIKELYHOOD OF CONSIDERABLE BLOWING SNOW AND BITTER COLD WIND CHILLS (15 TO 30 BLO ZERO) BY TONIGHT. BARAGA COUNTY MAY BE FAR ENOUGH INLAND TO ESCAPE STRONGEST WINDS AND HEAVIEST ACCUMS SO DID GO WITH SNOW AND BLOWING SNOW ADVISORY THERE. KEWEENAW COUNTY WILL SEE MARGINAL ADVISORY ACCUMS AS ISLE ROYALE WILL LIMIT FETCH EVEN MORE THERE IN NW FLOW...BUT STILL WINDS WILL RESULT IN ENOUGH BLOWING SNOW TO JUSTIFY ADVISORY THERE AS WELL. LOOK FOR LES TO TAPER OFF LATE TONIGHT AND THURSDAY AS INVERSION HGTS LOWER AND SNOW GROWTH BCMS LESS FAVORABLE. WINDS WILL ALSO COME DOWN SO DID NOT EXTEND HEADLINES INTO THU FOR WEST. THE ERN COUNTIES ON THE OTHER HAND...WILL HAVE BENEFIT OF LONGER FETCH..MNORE SUSTAINED PERIOD OF HIGHER INVERSION HGTS (7KFT) AND FOCUSED 950 MB CONV SHOULD RESULT IN WARNING LES ACCUMS OVER ALGER-LUCE AND NRN SCHOOLCRAFT TODAY INTO THU. LOCAL GUIDANCE SUGGESTS TOTAL AMTS OF 9-15 INCHES OVER THESE COUNTIES BY THU EVNG. THU NIGHT INTO FRI...PATTERN CHANGES LITTLE ALTHOUGH WINDS VEER SLIGHTLY MORE NNW BY FRI ALLOWING LES BANDS TO REACH ACROSS MORE OF UPPER MICHIGAN. SO WENT WITH LIKELY POPS ACROSS MUCH OF NRN TIER WITH CHC POPS SOUTH. TEMPS WILL REMAIN WELL BLO NORMAL WITH THE POTENTIAL FOR BITTER COLD WIND CHILLS OF 15 TO 30 BELOW THU NIGHT/FRI MORNING. && MQT WATCHES/WARNINGS/ADVISORIES... WINTER STORM WARNING TODAY AND TONIGHT MIZ002-003-084. WINTER STORM WARNING TODAY THROUGH THURSDAY MIZ006-007-085. LAKE EFFECT SNOW AND BLOWING SNOW ADVISORY TODAY AND TONIGHT MIZ001-004. HEAVY FREEZING SPRAY WARNING IN EFFECT LAKE SUPERIOR. && $$ VOSS mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE ALBUQUERQUE NM 1040 AM MST WED JAN 28 2004 .UPDATE...LEADING EDGE OF A VERY SHALLOW ARCTIC AIR MASS DRAPED ACROSS FAR SOUTHEAST COLORADO INTO SOUTHWEST KANSAS. LITTLE EVIDENCE THAT BOUNDARY IS GOING TO SAG MUCH FARTHER SOUTH THIS AFTERNOON DUE TO INCREASED MIXING TO ITS WEST AND SOUTH IN RESPONSE TO PRESSURE FALLS FROM THE CENTRAL TEXAS PANHANDLE INTO EAST CENTRAL NEW MEXICO. COLDER AIR MASS MAY BLEED INTO OUR NORTHEAST CORNER LATER TODAY/TONIGHT BUT ITS IMPACT WILL BE MINIMAL. AS A RESULT HAVE UPDATED GRIDS TO RAISE MAX TEMPS ABOUT 4-5 DEGREES ACROSS THE NORTHEAST QUARTER FOR TODAY. MEANWHILE...POTENT LOW PRESSURE AREA OVER SOUTHWEST ARIZONA STILL EXPECTED TO PASS FAR ENOUGH WEST AND SOUTH TO KEEP ALL POPS ZERO ACROSS OUR WC/SW ZONES. PARTLY TO MOSTLY CLOUDY SKIES STILL REASONABLE AFOREMENTIONED AREAS PER PREVIOUS FORECAST. KJ && .PREV DISCUSSION...CONCERNS IN THE SHORT TERM LIE WITH AN ARCTIC FRONT MOVING DOWN THE CENTRAL PLAINS AND MID/HIGH LEVEL CLOUDS APPROACHING FROM THE WEST. FARTHER OUT WILL BE TIMING OF THE DEVELOPMENT OF A BROAD COLD TROUGH OVER MUCH OF THE WESTERN AND CENTRAL U.S. THIS COMING WEEKEND. FIRST...THE UPPER LOW OVER NEVADA TO REMAIN WEST AND PASS SOUTH OF CWA. MODELS SLOW THE LOW IT DOWN AND MOVE IT SOUTH INTO WRN AZ TONIGHT AND WELL SOUTH INTO OLD MEXICO THURSDAY. TOOK OUT ALL MENTION OF POPS ACROSS THE WEST TODAY AND TONIGHT AND ONLY INCREASED THE CLOUD COVER. THE CLOUDS COULD AFFECT MAX TEMPS AND LOWERED JUST BELOW GUIDANCE NUMBERS. THURSDAY LOOKS FINE ACROSS THE WEST WITH SLIGHTLY WARMER TEMPS. NOW FOR THE NORTHEAST...ARCTIC FRONT MAKING STEADY SOUTHWARD PROGRESS ACROSS KANSAS AND NE COLORADO. RUC HAS IT MOVING INTO NE UNION COUNTY BEFORE NOON AND VERY SLOWLY SINKS IT SOUTHWARD THROUGH THURSDAY. QUESTION REMAINS HOW COLD AND HOW FAR SOUTH. COLDEST AIR REMAINS NORTH AND EAST...BUT WITH THE SHALLOW NATURE OF THE AIRMASS THE MODELS ARE LIKELY NOT HANDLING THIS WELL. WILL MAINTAIN TREND OF PREVIOUS FORECASTER AND GO BELOW GUIDANCE AT KCAO TODAY SPREADING THE COLD AIR SOUTH...JUST NORTH OF KCVS...AND SLIGHTLY WEST...RATON TO CONCHAS...TONIGHT AND THU. LATER SHIFTS WILL HAVE TO KEEP AND EYE ON THE PROGRESS OF THIS FRONT AS THESE KINDS OF FRONTS CAN LEAD TO BIG BUST...SEE MY PREDECESSORS DISCUSSION. THE REST OF THE CWA SHOULD SEE FAIR WX AND MILD TEMPS TODAY AND THURSDAY. BIG WARM UP ACROSS MUCH OF THE CWA ON FRIDAY...ESPECIALLY EAST AS LEE TROUGH AND DOWNSLOPING DEVELOPS. LATEST GRIDS NEEDED LITTLE ADJUSTMENTS. NEXT SYSTEM LOOKING BETTER IN RESPECT TO MUCH NEEDED PRECIPITATION. ALL MED RANGE MODELS COMING TOGETHER IN DEVELOPING A BROAD COLD TROUGH ACROSS MUCH OF THE COUNTY THIS COMING WEEKEND. ONLY TIMING OF INDIVIDUAL SHORTWAVES REMAIN IN QUESTION. OVERALL... INCREASED POPS FIRST ACROSS THE NORTH ON SATURDAY AND SPREAD THE GOOD NEWS SOUTH SAT NIGHT AND SUNDAY. LEFT MON AND TUE ALONE WITH UNCERTAINTY OF TIMING AND IF THE TROUGH SHIFTS FAR ENOUGH EASTWARD. THUS...TWEAKING OF THE GRIDS ARE LIKELY AS THIS SYSTEM TAKES SHAPE AND WE GET A BETTER HANDLE OF THE DETAILS AS THE TIMEFRAME NEARS. GB && .ABQ WATCHES/WARNINGS/ADVISORIES...NONE. && $$ 49 nm AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON NC 1012 AM EST WED JAN 28 2004 .DISCUSSION... WILL INCREASE TEMPERATURES A COUPLE OF DEGREES BASED ON LOCAL TEMPERATURE SCHEME AND NUMERICAL GUIDANCE. 12Z RUC FIELDS SHOWING WIND AT 925 MB TO BE RUNNING AROUND 25 TO 30 AND SHOWING A SLOW DECREASE THROUGH THE AFTERNOON. SO CURRENT WIND GUST IN FORECAST LOOK OKAY. OTHERWISE NO OTHER CHANGES PLANNED FOR THE MORNING UPDATE. && .MARINE... WILL KEEP SMALL CRAFT ADVISORY GOING THROUGH THE AFTERNOON HOURS AS COLD ADVECTION CONTINUES ACROSS THE COASTAL WATERS. GUSTS EVEN AT FRYING PAN BUOY HAVE COME DOWN TO UNDER 30 KT...SO WILL DROP MENTION OF GUSTS OVER THE COLDER NEARSHORE WATERS. WILL ALSO DROP SEAS A FOOT AS THE FPSN7 TOWER ONLY HAS 6 FT WITH THE OFFSHORE FLOW. NOMOGRAM FOR THIS FETCH DIRECTION GIVES ABOUT 5 FT AT 20 NM. WILL ALSO MAKE SOME EDITS TO THE MARINE WIND GRIDS TO IMPROVE NEARSHORE RESOLUTION. && .AVIATION... VFR. TIGHTEST PRESSURE GRADIENT THIS MORNING. NORTHWEST WIND GUSTS OF 20 TO 26 KTS EXPECTED EARLY...GRADUALLY TAPERING OFF DURING THE AFTERNOON AS GRADIENT SLOWLY DECREASES. LIGHT AND VARIABLE WINDS OVERNIGHT AS WINDS DECOUPLE. && .PRELIMINARY POINT TEMPS/POPS... WILMINGTON 45 25 53 34 / 0 0 0 0 LUMBERTON 44 24 52 33 / 0 0 0 0 FLORENCE 46 24 55 33 / 0 0 0 0 MYRTLE BEACH 46 26 54 35 / 0 0 0 0 && .ILM WATCHES/WARNINGS/ADVISORIES... NC...SMALL CRAFT ADVISORY AMZ250-252. SC...SMALL CRAFT ADVISORY AMZ254-256. && $$ PUBLIC: HAWKINS MARINE: TRA AVIATION: ROSS nc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON OH 900 PM EST WED JAN 28 2004 .DISCUSSION... CWFA WILL CONTINUE TO BE UNDER THE INFLUENCE OF A NWLY FLOW ALOFT. PREVIOUS 12Z RUNS AND LATEST RUC40 DEPICT MINOR DISTURBANCES IN THE NWLY FLOW ALOFT TO RIPPLE ACRS THE REGION OVERNIGHT. THESE DISTURBANCES ...IN COMBINATION WITH WEAK ISENTROPIC LIFT NOTED AROUND THE 280 K LEVEL...SHOULD BE ENOUGH TO PRODUCE A CHANCE OF FLURRIES...MAINLY ACROSS THE NRN 2/3 OF THE CWFA. HAVE RECENTLY NOTICED THAT LATEST FWA OBSERVATION SHOWED VSBYS AS LOW AS 1 3/4 OF A MILE...AND THIS WAS NOT LOCATED OVER THE HIGHEST RETURN ECHOES FROM IWX RADAR. WILL PONDER A CHC OF LIGHT SNOW IN THE NORTH INSTEAD OF FLURRIES BASED ON THIS INFORMATION...BUT WILL ALLOW FOR A FEW MORE RADAR SCANS GO BY IN ORDER TO DECIDE IF I WILL GO THAT ROUTE. OTHERWISE...TEMPS ARE ON THE WARMER SIDE COMPARED TO HOURLY GRIDS CURRENTLY OUT. WEAK WAA ALOFT...PROVIDING FOR CLOUD COVER...MAY KEEP TEMPS FROM FALLING TO CURRENT FORECAST LOWS. THE ONE FLY IN THE OINTEMENT IS THAT THE LOW LVL FLOW BEGINS TO SWITCH FROM THE W THEN NW...WHICH MAY ALLOW SOME COLDER AIR TO ADVECT SE INTO OUR AREAS. WILL TWEAK TEMPS UP ABOUT 3 DEGREES BASED ON ABOVE THOUGHTS. && .ILN WATCHES/WARNINGS/ADVISORIES... IN...NONE. KY...NONE. OH...NONE. && $$ oh AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE PITTSBURGH PA 325 PM EST WED JAN 28 2004 PER RECENT RADAR DATA AND RUC RUN, EXPECT LAKE-INDUCED OROGRAPHICALLY-ENHANCED SNOW SHOWERS TO SLOWLY ABATE TONIGHT. WINDS ALSO SHOULD LESSEN. NEXT JET-STREAK SYSTEM WILL DEVELOP A SECONDARY COLD FRONT THAT WIL BRING SCATTERED SNOW SHOWERS LATE THURSDAY. THE RENEWED NORTHWEST FLOW ACROSS THE GREAT LAKES WILL KEEP SNOW SHOWERS INTO FRIDAY. AFTER SOME HIGH PRESSURE THIS WEEKEND GIVES DRY CONDITIONS BUT LITTLE MODERATION IN TEMPERATURE...GFS ECMWF AND UKMET SHOW A STORMY PATTERN FOR NEXT WEEK. PER HPC DISCUSSION...GFS MAY HAVE BETTER TRACK WITH AN EAST COAST LOW CENTER...BUT SLOWER UKMET MAY HAVE BEST TIMING. FOR NOW MENTIONED FIRST CHANCE OF SNOW MONDAY...WITH IT POSSIBLY FREEZING RAIN SOUTH OF INTERSTATE 70. FOR TEMPERATURES WENT CLOSER TO COLDER GFS MOS VALUES. ...GIORDANO .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE OH...NONE PA...NONE WV...NONE $$ pa AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE ABERDEEN SD 355 PM CST WED JAN 28 2004 .SHORT TERM...TONIGHT THROUGH SATURDAY NIGHT FORECAST CONCERN WILL BE SNOW POTENTIAL TONIGHT ALONG WITH TEMPERATURES/WIND CHILLS. WATER VAPOR IMAGERY SHOWING NEXT FAST WAVE IN NORTHWEST FLOW TO AFFECT CWA LATER THIS EVENING CURRENTLY ACROSS NORTHWEST MONTANA. CLASSIC WAA SIGNAL IN KGGW WSR-88D AND THIS AREA OF ISENTROPIC LIFT WILL GRADUALLY WORK INTO CWA LATER THIS EVENING. BROAD AREA OF SURFACE PRESSURE FALLS ON ORDER OF 6-7 MB ALSO POISED ACROSS CENTRAL MONTANA AHEAD OF THIS WAVE. RUC/MESOETA INDICATING STRENGTHENING FRONTOGENESIS IN THE 850-700 HPA LAYER AS THIS WAVE DROPS SOUTHWEST AND FLOW INTERACTS WITH STRONG LOW LEVEL BAROCLINIC ZONE. ETA MIXING RATIOS ON 280K SURFACE DO INCREASE TO NEARLY 2 G/KG ACROSS WESTERN PORTION OF CWA BY 06Z. GIVEN GOOD FRONTOGENESIS DROPPING INTO CWA TONIGHT ALONG WITH WAA/ISENTROPIC LIFT...WILL INCREASE POPS TO LIKELY ACROSS MOST OF CWA TONIGHT. SNOW/LIQUID RATIOS STILL RUNNING RELATIVELY HIGH AND WILL NOT TAKE MUCH WATER TO DROP A QUICK 1 TO 2 INCHES ACROSS MOST AREAS TONIGHT. SHOULD SEE TEMPERATURES SLOWLY INCREASING THROUGH THE EVENING ACROSS WESTERN HALF OF CWA AS EAST WINDS INCREASE A BIT WITH TIGHTENING SURFACE PRESSURE GRADIENT. GIVEN COMBINATION OF SNOWFALL AND WIND CHILLS GETTING BACK INTO ADVISORY RANGE...WILL GO AHEAD AND ISSUE WINTER WEATHER ADVISORY OVERNIGHT FOR ALL BUT FAR SOUTHWEST PORTION OF CWA. WITH SURFACE RIDGE AXIS SLOW TO EXIT FAR EASTERN CWA...WILL KEEP MORE OF A STEADY TEMPERATURE TREND. FOR THURSDAY MORNING...WILL RETAIN SMALL POPS ACROSS THE EASTERN CWA AS WAVE DROPS SOUTHEAST INTO SOUTHERN MINNESOTA. SOME MID LEVEL DRYING WITH WEAK SUBSIDENCE BEHIND THIS SHORT WAVE BUT ETA/GFS TIME SECTIONS STILL SHOWING PLENTY OF HIGH RH IN LOW/MID LEVELS. OVERALL NOT EXPECTING MUCH MOVEMENT OF ARCTIC BOUNDARY THROUGH FRIDAY SO AFTERNOON TEMPS SHOULD STAY BELOW ZERO ONCE AGAIN ACROSS EASTERN CWA ON THURSDAY. ALMOST LIKE CLOCKWORK IT SEEMS...NEXT WAVE IN NORTHWEST FLOW APPEARS POISED TO DROP INTO CWA FOR THURSDAY NIGHT. DYNAMICS LOOKING LESS IMPRESSIVE WITH THIS WAVE...BUT WITH STRONG BAROCLINIC ZONE IN PLACE WILL INTRODUCE SMALL CHANCE POPS FOR LIGHT SNOW ACROSS CWA. ATTENTION THEN TURNS TO FRIDAY WITH MORE AMPLIFIED SYSTEM AFFECTING THE NORTHERN PLAINS. MODELS BEGINNING TO CONVERGE ON A COMMON SOLUTION WITH THIS UPPER WAVE. BOTH TAKE MID LEVEL HEIGHT MINIMUM NORTH OF CWA WITH ETA A BIT SLOWER THAN GFS/ECMWF. HAVE ACCEPTED THE SLIGHTLY SLOWER ETA WHICH ALSO AGREES WITH NCEP ENSEMBLE MEAN. WILL KEEP LIGHT SNOW CHANCES GOING FOR FRIDAY NIGHT/SATURDAY WITH GOOD MID LEVEL WAA AHEAD OF THIS AMPLIFIED WAVE. .LONG TERM...SUNDAY THROUGH WEDNESDAY FOR SUNDAY GOOD SUBSIDENCE BEHIND UPPER WAVE SHOULD ALLOW FOR DECREASING CLOUDS AND A REINFORCING SHOT OF CAA. MAIN DIFFERENCE BETWEEN GFS/ECMWF FOR THIS PERIOD IS STRENGTH OF SOUTHERN STREAM SYSTEM DIVING INTO CENTRAL PLAINS. ECMWF MAY BE TOO AMPLIFIED WITH THIS WAVE AND HAVE TRENDED TOWARD LESS AMPLIFIED CANADIAN/GFS FOR THIS PERIOD. WITH MEAN RIDGE ACROSS EASTERN PACIFIC...SHOULD SEE CONTINUED COLD PATTERN WITH JUST WEAK WAVES DROPPING INTO AREA BUT NOTHING TO WARRANT POP MENTIONS AT THIS POINT. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...WINTER WEATHER ADVISORY FOR NORTH CENTRAL AND NORTHEAST SD TONIGHT. MN...WINTER WEATHER ADVISORY FOR BIG STONE AND TRAVERSE COUNTIES TONIGHT. && $$ MARSILI sd AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY NATIONAL WEATHER SERVICE RAPID CITY SD 645 AM MST WED JAN 28 2004 .DISCUSSION...12Z KUNR SOUNDING ABOUT 3C COLDER IN THE LOWER TROPOSPHERE THAN EXPECTED. HENCE...CURRENT HIGHS OVER THE SD PLAINS OVERDONE. WILL CHOP ABOUT 5F OFF CURRENT FORECAST AND HOPE IT MAKES IT THAT ...WARM... 12Z RUC SUPPORTS. .UNR WATCHES/WARNINGS/ADVISORIES... .SD...WIND CHILL ADVISORY THIS AM NW SD. .WY...NONE. $$ HELGESON sd AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NASHVILLE TN 930 AM CST WED JAN 28 2004 DISCUSSION...COLD MORNING ACROSS MIDDLE TENNESSEE WITH MORNING LOWS DOWN IN THE TEENS. SATELLITE SHOWING CLEAR SKIES ACROSS THE MID STATE WITH HIGH PRESSURE CENTERED IN THE DELTA REGION. SURFACE HIGH SHOWS VERY LITTLE EASTWARD PROGRESS DURING THE DAY AND FLATTENS OUT INTO SOMEWHAT OF A DIRTY SURFACE RIDGE PER LATEST RUC RUN LATE IN THE DAY. LAMP DATA HAS NO PROBLEM TAKING TEMPS INTO THE MID AND UPPER 30S FOR AFTERNOON HIGHS. WILL UPDATE AND MAKE MINOR TWEAKS WHERE NEEDED. UPDATED ZONES OUT AROUND 10 AM. && .BNA WATCHES/WARNINGS/ADVISORIES...NONE. && $$ BOYD 01 tn AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE SAN ANGELO TX 955 PM CST WED JAN 28 2004 .UPDATE... OKAY...BASED ON LATEST RUC AND ASSOCIATED SURFACE ANALYSIS...WE NOW BELIEVE THIS COLD FRONT WILL NOT MAKE IT INTO THE FAR NORTHERN BIG COUNTRY UNTIL AROUND NOON TOMORROW. AROUND THAT TIME...WE EXPECT THE FRONT TO MOVE INTO HASKEL COUNTY AND THROCKMORTON COUNTY. BY 00Z TOMORROW AFTERNOON...WE EXPECT THE FRONT TO BE THROUGH THE CONCHO VALLEY AND THE HEARTLAND. BY 06Z (MIDNIGHT LOCAL) TOMORROW NIGHT...WE EXPECT THE FRONT TO BE MOVING JUST SOUTH OF INTERSTATE 10 AND OUT OF OUR AREA. THUS...WE ARE CURRENTLY WORKING ON UPDATING OUR GRIDS AND OUR OTHER FORECAST PACKAGES. SPECIFICALLY...WE WILL INCREASE OVERNIGHT LOWS FOR MAINLY THE BIG COUNTRY AND AFTERNOON HIGHS TOMORROW ACROSS THE BOARD FOR ALL OF WEST CENTRAL TEXAS. ALSO...WE WILL ADJUST SURFACE WINDS TO REFLECT OUR NEW THINKING ON FRONTAL PASSAGE TIMING. IN ADDITION...WE WILL INCREASE CLOUD COVER (TO CLOUDY) ACROSS MOST OF WEST CENTRAL TEXAS GIVEN THE CURRENT STRATUS MOVING INTO AND ACROSS OUR SOUTHERN AND CENTRAL ZONES. BY TOMORROW MORNING...WE EXPECT CLOUDY SKIES TO DOMINATE WEST CENTRAL TEXAS WITH A GRADUAL CLEARING FROM THE WEST BEGINNING AROUND NOON. THANKS TO NATIONAL WEATHER SERVICE FORECAST OFFICE FORT WORTH FOR THE OUTSTANDING TELEPHONE COORDINATION AND A SPECIAL THANKS TO OUR BIG COUNTRY MEDIA PARTNER FOR THE TELEPHONE COORDINATION THIS EVENING AS WELL. && .PREV DISCUSSION... TEXAS... LEADING EDGE OF SOME BONIFIDE ARCTIC AIR SITUATED ALONG THE KANSAS/OKLAHOMA BORDER. SOUTHWARD PUSH HAS SLOWED TODAY...FOR AWAITING DESERT SOUTHWEST UPPER LOW AND ASSOCIATED LEE SURFACE TROUGH TO GET OUT OF THE WAY. THAT SHOULD HAPPEN TONIGHT...AS THE UPPER LOW DIGS SOUTH INTO NORTHERN MEXICO. THAT LEAVES THE BARN-DOOR OPEN...BRINGING THE LEADING EDGE OF ARCTIC AIR INTO ABILENE BY SUNRISE THURSDAY. THE ARCTIC AIR SHOULD CONTINUE OOZING SOUTH THURSDAY...PROBABLY REACHING SAN ANGELO AROUND NOON AND I-10 BY LATE AFTERNOON. REAL CRAP-SHOOT HERE. ARCTIC AIR RATHER SHALLOW...AND MAY ONLY INFLUENCE THE BIG COUNTRY. AND WHAT IF IT STALLS? TEMPERATURE BUST POTENTIAL CENTRAL AND SOUTH OFF THE CHARTS. OTHER PLAYER IS DRIZZLE AND LIGHT FOG EVENT ACROSS THE HEARTLAND AND NORTHWEST HILL COUNTRY LATE TONIGHT AND EARLY THURSDAY IN WAA REGIME. CLOUDS FUNNELING UP THE RIO GRANDE VALLEY WILL OVERSPREAD THE FORECAST AREA FROM NORTH TO SOUTH TONIGHT...THEN HANG THURSDAY. THANKS LBB/OUN/FWD FOR THE COORDINATION. BEING SHALLOW...ARCTIC AIR SHOULD MODIFY FRIDAY INTO SATURDAY... ALLOWING FOR SEASONAL TEMPERATURES. BUT ANOTHER UPPER LEVEL DISTURBANCE PROMISES TO YANK DOWN SOME MORE ARCTIC AIR LATE SUNDAY AND ESPECIALLY MONDAY. HAVE UNDERCUT MEX BIG-TIME SUNDAY THROUGH WEDNESDAY TO TAKE NEXT INTRUSION INTO ACCOUNT. && .SJT WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 23/HUBER tx AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE FORT WORTH TX 850 PM CST WED JAN 28 2004 .UPDATE... THE MOVEMENT OF THE ARCTIC COLD FRONT CONTINUES TO CAUSE GREAT CONCERN AND GREAT UNCERTAINTY REMAINS. THE LATEST SURFACE ANALYSIS SHOWS THAT THE FRONT IS MOVING SOUTH...AND AS OF 02Z...EXTENDED JUST SOUTH OF BARTLESVILLE OKLAHOMA...TO BORGER TEXAS LINE. THE FRONT SHOULD MOVE SOUTH TO NEAR AN OKLAHOMA CITY TO WICHITA FALLS LINE BY AFTER DAYBREAK THURSDAY. HAVE ONCE AGAIN SLOWED THE FORWARD PROGRESSION OF THE FRONT. IT MAY MOVE TO NEAR A PARIS...TO STEPHENVILLE LINE BY 00Z. THE FRONT/S MOVEMENT SHOULD ACCELERATE LATE TOMORROW AFTERNOON INTO TOMORROW NIGHT AS THE UPPER TROUGH MOVES INTO THE AREA. THUS HAVE BUMPED HIGHS UP A BIT...BUT THEY STILL MAY BE TOO LOW. THE CLOUD COVER MAY HELP KEEP TEMPERATURES DOWN SOME...BUT THE WARM ADVECTION AHEAD OF THE FRONT MAY OVERCOME THIS AND ALLOW TEMPERATURES TO STILL WARM A COUPLE OF CATEGORIES ABOVE THE NEW FORECAST. #58 && .AVIATION... 522 PM CST WED JAN 28 2004 LOW AND MID LEVEL CLOUDS ALREADY ACROSS MUCH OF SOUTH TEXAS LATE THIS AFTERNOON AND WITH 25 KT SW FLOW PROGGED TO DEVELOP BY 06Z...WILL NEED TO BRING SOME CIGS INTO METRO AIRPORTS BY 07Z AND THEN DROP THEM TO MVFR BY 12Z AS FRONT MOVES CLOSER TO REGION. KACT WILL NEED LOW CLOUDS SOONER. MVFR CIGS WILL LINGER THROUGH THE REST OF THE PERIOD. 80 && .PREV DISCUSSION... 345 PM CST WED JAN 28 2004 VERY COMPLICATED FORECAST TODAY. YESTERDAY...THE ARCTIC AIRMASS HEADING SOUTH THROUGH THE NORTHERN PLAINS PROMPTED SIGNIFICANT CHANGES TO THE FORECAST FOR THURSDAY AND FRIDAY. THE FRONT HAS MADE IT TO NORTHWESTERN OKLAHOMA AND SLOWED SIGNIFICANTLY. HOWEVER...RECENT OBSERVATIONS SUGGEST THAT THIS SLOW DOWN IS TEMPORARY AND WILL NOT LAST. THIS AFTERNOON...ANALYSIS HAVE SHOWN A SIGNIFICANT ISALLOBARIC GRADIENT DEVELOPING DUE TO RAPID SURFACE PRESSURE FALLS OVER W TX. AT 21Z... PRESSURE FALLS OF NEARLY 5 MB IN 3 HOURS ARE OBSERVED EAST OF LUBBOCK. ALTHOUGH THE PRESSURE RISES NORTH OF THE FRONT HAVE DISSIPATED (TEMPORARILY)...THE NET ISALLOBARIC GRADIENT RESULTING FROM PRESSURE FALLS TO IT'S SOUTH ARE CAUSING THE FRONT TO BEGIN MOVING AGAIN. WE ARE ALREADY SEEING THIS AS SOME OF THE REPORTING STATIONS IN NORTHERN OKLAHOMA ARE INDICATING THAT WINDS HAVE BACKED MORE TO THE NORTHEAST AND INCREASED TO 20KT JUST SINCE 20Z. THUS... WE EXPECT THE FRONT TO ACCELERATE THIS EVENING...AND ESPECIALLY AFTER SUNSET. ALTHOUGH WE HAVE SLOWED FROPA ABOUT 6 HOURS FROM WHAT WE HAD IN YESTERDAY'S AFTERNOON PACKAGE... IT IS STILL CONSIDERABLY FASTER AND STRONGER THAN MODELS HAVE INDICATED. THE 18Z RUC IS NOW THE FIRST MODEL TO SHOW A SIGNIFICANT ACCELERATION TO THE SOUTH OVERNIGHT TONIGHT...BUT STILL A BIT SLOW IN OUR OPINION. FRONT SHOULD MOVE ACROSS RED RIVER AROUND OR SHORTLY BEFORE SUNRISE...AND THEN TO CENTRAL ZONES BY MID TO LATE MORNING. TEMPERATURES OVER NW ZONES SHOULD PEAK DURING THE MORNING THEN FALL DURING THE AFTERNOON. SE ZONES SHOULD WARM INTO THE 50S BEFORE FROPA LATE IN THE DAY. CURRENTLY... ISENTROPIC LIFT IS INCREASING TO THE SOUTH AND LOW-LEVEL MOISTURE/STRATUS IS SURGING NORTH THROUGH SOUTHERN TEXAS THIS AFTERNOON. WE ESTIMATE MOVEMENT AT ABOUT 20 KT TO THE NORTH. AT THIS RATE...CLOUDS SHOULD INCREASE IN EXTREME SOUTHERN ZONES SHORTLY AFTER 00Z...AND SPREAD INTO THE WACO AREA BY 0500Z. WITH CLOUDS INCREASING TONIGHT...AND WAA OVER THE AREA... TEMPERATURES WILL STAY ABOVE FREEZING ALL ZONES. FORECAST LOWS TONIGHT MARK THE MOST SIGNIFICANT CHANGE TO OUR PREVIOUS FORECAST PACKAGE THANKS TO THE LATER-THAN-EXPECTED FROPA. FURTHERMORE...WE HAVE PLACED LOW POPS OVER THE SOUTHEAST WHERE SOME VERY LIGHT RAIN OR SPRINKLES MAY FALL THROUGH MID-AFTERNOON THURSDAY. ISENTROPIC LIFT WILL END LATE THURSDAY AS THE UPPER-LEVEL TROUGH AXIS PASSES. THIS WILL HELP TO CLEAR SKIES AND END LIGHT RAIN CHANCES OVER SOUTHEASTERN ZONES BY EVENING. IT APPEARS THAT A BRIEF WARMUP SATURDAY AND SUNDAY WILL BE REPLACED BY SHARPLY COLDER WEATHER MONDAY. FROPA SHOULD OCCUR SUNDAY AFTERNOON...POSSIBLY WITH FALLING TEMPERATURES DURING THE DAY. HOWEVER...WE SEE NOTHING IN THE WAY OF FORCING AT THIS TIME THAT WOULD SUGGEST ANY CHANCES FOR PRECIPITATION ARE WARRANTED. ROBBINS && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 40 44 25 36 / 0 0 0 0 WACO, TX 43 55 33 46 / 0 30 0 0 PARIS, TX 38 42 24 34 / 0 0 0 0 DENTON, TX 39 40 25 36 / 0 0 0 0 MCKINNEY, TX 38 41 24 35 / 0 0 0 0 DALLAS, TX 40 44 25 36 / 0 0 0 0 TERRELL, TX 41 45 26 37 / 0 20 0 0 CORSICANA, TX 41 48 32 39 / 0 30 0 0 TEMPLE, TX 43 55 33 46 / 0 30 0 0 && .FWD WATCHES/WARNINGS/ADVISORIES... TX...NONE. && $$ tx AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE FORT WORTH TX 522 PM CST WED JAN 28 2004 .AVIATION... LOW AND MID LEVEL CLOUDS ALREADY ACROSS MUCH OF SOUTH TEXAS LATE THIS AFTERNOON AND WITH 25 KT SW FLOW PROGGED TO DEVELOP BY 06Z...WILL NEED TO BRING SOME CIGS INTO METRO AIRPORTS BY 07Z AND THEN DROP THEM TO MVFR BY 12Z AS FRONT MOVES CLOSER TO REGION. KACT WILL NEED LOW CLOUDS SOONER. MVFR CIGS WILL LINGER THROUGH THE REST OF THE PERIOD. 80 && .PUBLIC DISCUSSION... VERY COMPLICATED FORECAST TODAY. YESTERDAY...THE ARCTIC AIRMASS HEADING SOUTH THROUGH THE NORTHERN PLAINS PROMPTED SIGNIFICANT CHANGES TO THE FORECAST FOR THURSDAY AND FRIDAY. THE FRONT HAS MADE IT TO NORTHWESTERN OKLAHOMA AND SLOWED SIGNIFICANTLY. HOWEVER...RECENT OBSERVATIONS SUGGEST THAT THIS SLOW DOWN IS TEMPORARY AND WILL NOT LAST. THIS AFTERNOON...ANALYSIS HAVE SHOWN A SIGNIFICANT ISALLOBARIC GRADIENT DEVELOPING DUE TO RAPID SURFACE PRESSURE FALLS OVER W TX. AT 21Z... PRESSURE FALLS OF NEARLY 5 MB IN 3 HOURS ARE OBSERVED EAST OF LUBBOCK. ALTHOUGH THE PRESSURE RISES NORTH OF THE FRONT HAVE DISSIPATED (TEMPORARILY)...THE NET ISALLOBARIC GRADIENT RESULTING FROM PRESSURE FALLS TO IT'S SOUTH ARE CAUSING THE FRONT TO BEGIN MOVING AGAIN. WE ARE ALREADY SEEING THIS AS SOME OF THE REPORTING STATIONS IN NORTHERN OKLAHOMA ARE INDICATING THAT WINDS HAVE BACKED MORE TO THE NORTHEAST AND INCREASED TO 20KT JUST SINCE 20Z. THUS... WE EXPECT THE FRONT TO ACCELERATE THIS EVENING...AND ESPECIALLY AFTER SUNSET. ALTHOUGH WE HAVE SLOWED FROPA ABOUT 6 HOURS FROM WHAT WE HAD IN YESTERDAY'S AFTERNOON PACKAGE... IT IS STILL CONSIDERABLY FASTER AND STRONGER THAN MODELS HAVE INDICATED. THE 18Z RUC IS NOW THE FIRST MODEL TO SHOW A SIGNIFICANT ACCELERATION TO THE SOUTH OVERNIGHT TONIGHT...BUT STILL A BIT SLOW IN OUR OPINION. FRONT SHOULD MOVE ACROSS RED RIVER AROUND OR SHORTLY BEFORE SUNRISE...AND THEN TO CENTRAL ZONES BY MID TO LATE MORNING. TEMPERATURES OVER NW ZONES SHOULD PEAK DURING THE MORNING THEN FALL DURING THE AFTERNOON. SE ZONES SHOULD WARM INTO THE 50S BEFORE FROPA LATE IN THE DAY. CURRENTLY... ISENTROPIC LIFT IS INCREASING TO THE SOUTH AND LOW-LEVEL MOISTURE/STRATUS IS SURGING NORTH THROUGH SOUTHERN TEXAS THIS AFTERNOON. WE ESTIMATE MOVEMENT AT ABOUT 20 KT TO THE NORTH. AT THIS RATE...CLOUDS SHOULD INCREASE IN EXTREME SOUTHERN ZONES SHORTLY AFTER 00Z...AND SPREAD INTO THE WACO AREA BY 0500Z. WITH CLOUDS INCREASING TONIGHT...AND WAA OVER THE AREA... TEMPERATURES WILL STAY ABOVE FREEZING ALL ZONES. FORECAST LOWS TONIGHT MARK THE MOST SIGNIFICANT CHANGE TO OUR PREVIOUS FORECAST PACKAGE THANKS TO THE LATER-THAN-EXPECTED FROPA. FURTHERMORE...WE HAVE PLACED LOW POPS OVER THE SOUTHEAST WHERE SOME VERY LIGHT RAIN OR SPRINKLES MAY FALL THROUGH MID-AFTERNOON THURSDAY. ISENTROPIC LIFT WILL END LATE THURSDAY AS THE UPPER-LEVEL TROUGH AXIS PASSES. THIS WILL HELP TO CLEAR SKIES AND END LIGHT RAIN CHANCES OVER SOUTHEASTERN ZONES BY EVENING. .EXTENDED... IT APPEARS THAT A BRIEF WARMUP SATURDAY AND SUNDAY WILL BE REPLACED BY SHARPLY COLDER WEATHER MONDAY. FROPA SHOULD OCCUR SUNDAY AFTERNOON...POSSIBLY WITH FALLING TEMPERATURES DURING THE DAY. HOWEVER...WE SEE NOTHING IN THE WAY OF FORCING AT THIS TIME THAT WOULD SUGGEST ANY CHANCES FOR PRECIPITATION ARE WARRANTED. ROBBINS DALLAS-FT. WORTH, TX 40 44 25 36 / 0 0 0 0 WACO, TX 43 55 33 46 / 0 30 0 0 PARIS, TX 38 42 24 34 / 0 0 0 0 DENTON, TX 39 40 25 36 / 0 0 0 0 MCKINNEY, TX 38 41 24 35 / 0 0 0 0 DALLAS, TX 40 44 25 36 / 0 0 0 0 TERRELL, TX 41 45 26 37 / 0 20 0 0 CORSICANA, TX 41 48 32 39 / 0 30 0 0 TEMPLE, TX 43 55 33 46 / 0 30 0 0 && .FWD WATCHES/WARNINGS/ADVISORIES... TX...NONE. && $$ tx AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE FORT WORTH TX 345 PM CST WED JAN 28 2004 VERY COMPLICATED FORECAST TODAY. YESTERDAY...THE ARCTIC AIRMASS HEADING SOUTH THROUGH THE NORTHERN PLAINS PROMPTED SIGNIFICANT CHANGES TO THE FORECAST FOR THURSDAY AND FRIDAY. THE FRONT HAS MADE IT TO NORTHWESTERN OKLAHOMA AND SLOWED SIGNIFICANTLY. HOWEVER...RECENT OBSERVATIONS SUGGEST THAT THIS SLOW DOWN IS TEMPORARY AND WILL NOT LAST. THIS AFTERNOON...ANALYSES HAVE SHOWN A SIGNIFICANT ISALLOBARIC GRADIENT DEVELOPING DUE TO RAPID SURFACE PRESSURE FALLS OVER W TX. AT 21Z... PRESSURE FALLS OF NEARLY 5 MB IN 3 HOURS ARE OBSERVED EAST OF LUBBOCK. ALTHOUGH THE PRESSURE RISES NORTH OF THE FRONT HAVE DISSIPATED (TEMPORARILY)...THE NET ISALLOBARIC GRADIENT RESULTING FROM PRESSURE FALLS TO IT'S SOUTH ARE CAUSING THE FRONT TO BEGIN MOVING AGAIN. WE ARE ALREADY SEEING THIS AS SOME OF THE REPORTING STATIONS IN NORTHERN OKLAHOMA ARE INDICATING THAT WINDS HAVE BACKED MORE TO THE NORTHEAST AND INCREASED TO 20KT JUST SINCE 20Z. THUS... WE EXPECT THE FRONT TO ACCELERATE THIS EVENING...AND ESPECIALLY AFTER SUNSET. ALTHOUGH WE HAVE SLOWED FROPA ABOUT 6 HOURS FROM WHAT WE HAD IN YESTERDAY'S AFTERNOON PACKAGE... IT IS STILL CONSIDERABLY FASTER AND STRONGER THAN MODELS HAVE INDICATED. THE 18Z RUC IS NOW THE FIRST MODEL TO SHOW A SIGNIFICANT ACCELERATION TO THE SOUTH OVERNIGHT TONIGHT...BUT STILL A BIT SLOW IN OUR OPINION. FRONT SHOULD MOVE ACROSS RED RIVER AROUND OR SHORTLY BEFORE SUNRISE...AND THEN TO CENTRAL ZONES BY MID TO LATE MORNING. TEMPERATURES OVER NW ZONES SHOULD PEAK DURING THE MORNING THEN FALL DURING THE AFTERNOON. SE ZONES SHOULD WARM INTO THE 50S BEFORE FROPA LATE IN THE DAY. CURRENTLY... ISENTROPIC LIFT IS INCREASING TO THE SOUTH AND LOW-LEVEL MOISTURE/STRATUS IS SURGING NORTH THROUGH SOUTHERN TEXAS THIS AFTERNOON. WE ESTIMATE MOVEMENT AT ABOUT 20 KT TO THE NORTH. AT THIS RATE...CLOUDS SHOULD INCREASE IN EXTREME SOUTHERN ZONES SHORTLY AFTER 00Z...AND SPREAD INTO THE WACO AREA BY 0500Z. WITH CLOUDS INCREASING TONIGHT...AND WAA OVER THE AREA... TEMPERATURES WILL STAY ABOVE FREEZING ALL ZONES. FORECAST LOWS TONIGHT MARK THE MOST SIGNIFICANT CHANGE TO OUR PREVIOUS FORECAST PACKAGE THANKS TO THE LATER-THAN-EXPECTED FROPA. FURTHERMORE...WE HAVE PLACED LOW POPS OVER THE SOUTHEAST WHERE SOME VERY LIGHT RAIN OR SPRINKLES MAY FALL THROUGH MID-AFTERNOON THURSDAY. ISENTROPIC LIFT WILL END LATE THURSDAY AS THE UPPER-LEVEL TROUGH AXIS PASSES. THIS WILL HELP TO CLEAR SKIES AND END LIGHT RAIN CHANCES OVER SOUTHEASTERN ZONES BY EVENING. .EXTENDED... IT APPEARS THAT A BRIEF WARMUP SATURDAY AND SUNDAY WILL BE REPLACED BY SHARPLY COLDER WEATHER MONDAY. FROPA SHOULD OCCUR SUNDAY AFTERNOON...POSSIBLY WITH FALLING TEMPERATURES DURING THE DAY. HOWEVER...WE SEE NOTHING IN THE WAY OF FORCING AT THIS TIME THAT WOULD SUGGEST ANY CHANCES FOR PRECIPITATION ARE WARRANTED. ROBBINS DALLAS-FT. WORTH, TX 40 44 25 36 / 0 0 0 0 WACO, TX 43 55 33 46 / 0 30 0 0 PARIS, TX 38 42 24 34 / 0 0 0 0 DENTON, TX 39 40 25 36 / 0 0 0 0 MCKINNEY, TX 38 41 24 35 / 0 0 0 0 DALLAS, TX 40 44 25 36 / 0 0 0 0 TERRELL, TX 41 45 26 37 / 0 20 0 0 CORSICANA, TX 41 48 32 39 / 0 30 0 0 TEMPLE, TX 43 55 33 46 / 0 30 0 0 && .FWD WATCHES/WARNINGS/ADVISORIES... TX...NONE. && $$ tx AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LUBBOCK TX 320 PM CST WED JAN 28 2004 .SHORT TERM... EMPHASIS CONTINUING ON VERY SHALLOW AND VERY COLD AIRMASS OOZING SOUTHWARD NOW INTO SOUTHERN PLAINS MAINLY DUE TO SHEAR WEIGHT OF THE MASSIVE COLD AIR TO THE NORTH. FRONT CURRENTLY ENTERING NORTHERN TEXAS PANHANDLE WITH VERY SLIGHT SOUTHWARD PUSH. SHARP TEMPERATURE GRADIENT...50S TO 40S DIRECTLY BEHIND FRONT...BUT MUCH COLDER TEENS INTO SINGLE DIGITS NOT FAR BEHIND IN SOUTHWEST KANSAS. WE FAVOR THE RUC OVER THE NEXT 24 HOURS WITH SURFACE FRONT A BIT MORE AGGRESSIVE ACROSS NORTHWEST TEXAS THAN THE ETA...ENTERING THE SOUTH PLAINS SHORTLY BEFORE DAYBREAK THURSDAY. SLIGHTLY BETTER PUSH WITH APPROX 1000 FEET DEEPER COLDER AIR WILL OCCUR OFF THE CAPROCK. A LOW LEVEL WARM AIR ADVECTION PATTERN WILL BE ONGOING OVERNIGHT IN ADVANCE OF THE FRONT...HOWEVER...WITH DEWPOINTS RISING INTO THE 30S SOUTHEAST ZONES BY LATER TONIGHT. SOME RISK OF LOW CLOUDS AND DRIZZLE/FLURRIES MAINLY SOUTHEAST ZONES...BUT WILL NOT INDICATE IN GRIDS FOR NOW. RUC AND MESO-ETA BOTH FAVOR MIXING THURSDAY AFTERNOON FOLLOWING FRONT. SO...AFTER INITIAL MORNING COOLING...APPEARS THAT AT LEAST WESTERN ZONES ON THE CAPROCK WILL MIX INTO THE WARMER AIR ALOFT. THUS WILL INDICATE A SHARP EAST-WEST TEMPERATURE GRADIENT WITH MID TO UPPER 30S OFF THE CAPROCK AND 50S ON THE CAP. STILL SOME RISK THAT SOMEWHAT DEEPER COLDER AIR WILL OVERSPREAD WESTERN SOUTH PLAINS...BUT WE FAVOR THE MIXING SCENARIO AS INDICATED BY THE RUC WITH THE STRONGEST COLD AIR PUSH. HIGH CLOUDS TONIGHT AND THURSDAY MORNING APPEARS SHOULD CLEAR FOLLOWING UPPER TROF PASSAGE AROUND MIDDAY THURSDAY. UPPER LOW DIVING SOUTHEAST THROUGH SOUTHERN ARIZONA WILL CROSS NORTHERN MEXICO WITH NO IMPACT OUR AREA. MCQUEEN .LONG TERM... ANOTHER FORECAST CHALLENGE TODAY...AS SHALLOW ARCTIC AIRMASS HAS STRUGGLED TO MOVE TOWARD THE FA TODAY. UPPER LOW OVER SOUTHERN NEVADA/NORTHWEST ARIZONA EARLY THIS AFTERNOON CONTINUES TO MOVE SOUTHEAST. MODELS INDICATED THIS YESTERDAY AND ARE AGAIN SIMILAR ON THIS MORNINGS 12Z RUN. GFS/ETA AND CANADIAN MODELS ARE MOVING THE UPPER LOW SLIGHTLY FURTHER SOUTH INTO MEXICO FRIDAY MORNING BEFORE IT TRANSLATES EAST ACROSS THE LAREDO AREA FRIDAY AND INTO SOUTHEAST TEXAS FRIDAY NIGHT/SATURDAY. LATEST IR/WV LOOP SHOWS THIS FEATURE WELL AND MOVING SOUTHEAST AT 150 DEG 18KTS. WILL NOT DEVIATE MUCH FROM GUIDANCE TEMPERATURES FRIDAY AS WEAK RIDGING MOVES OVER THE REGION AND COLDEST AIR TO BE EAST OF THE FA. AGREE WITH PREVIOUS SHIFT IN THE THOUGHTS THAT WITH THIS TYPE OF SETUP THE COLDEST AIR GENERALLY STAYS EAST OF THE CAPROCK AND NORTHEAST COUNTIES OFF THE CAPROCK TAKE THE BRUNT OF THE COLD AIR. WILL KEEP CURRENT FORECAST FOR FRIDAY WITH MINOR TWEAKS OFF THE CAPROCK TO TEMPERATURES. SFC LEE CYCLOGENESIS OVER EASTERN PLAINS OF COLORADO AND NEW MEXICO SATURDAY IN ADVANCE OF ANOTHER UPPER TROUGH MOVING ONSHORE OVER THE PACIFIC NORTHWEST. SURFACE LOW TO DROP SOUTH INTO THE FA BRINGING ANOTHER SURGE OF COLD AIR INTO THE REGION SATURDAY NIGHT AND SUNDAY. THERE WILL BE A SLIGHT CHANCE OF LIGHT SNOW ACROSS THE NORTHERN CWFA SUNDAY/SUNDAY NIGHT WITH WEAK LIFT COMBINING WITH AN OVERRUNNING PATTERN. AIRMASS BEGINS TO MODERATE MONDAY...THEN MODELS INDICATE ANOTHER FRONT TO DIVE THROUGH THE FA TUESDAY/TUESDAY NIGHT BRINGING COOLER TEMPERATURES TO THE REGION ONCE AGAIN ON WEDNESDAY.THANKS AMA SJT ABQ FOR COORDINATION TODAY. XI && .PRELIMINARY POINT TEMPS/POPS... FRIONA 25 54 24 57 / 0 0 0 0 TULIA 23 50 24 54 / 0 0 0 0 PLAINVIEW 24 50 25 57 / 0 0 0 0 LEVELLAND 29 55 27 58 / 0 0 0 0 LUBBOCK 28 52 27 57 / 0 0 0 0 BROWNFIELD 32 57 29 60 / 0 0 0 0 CHILDRESS 21 36 24 47 / 0 0 0 0 SPUR 29 40 27 56 / 0 0 0 0 ASPERMONT 34 38 28 49 / 0 0 0 0 && .LUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 05/11 tx AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MIDLAND/ODESSA TX 223 PM CST WED JAN 28 2004 .SHORT TERM... A LEE SIDE TROUGH OVER THE PLAINS OF EASTERN CO/NM COMBINED WITH HIGH PRESSURE OVER THE LOWER MS RIVER VALLEY HAS BROUGHT SOUTH TO SOUTHWEST WINDS TO THE AREA TODAY. ELSEWHERE...ARCTIC COLD FRONT HAS EASED SOUTH INTO THE OK PANHANDLE AS OF 20Z. TOUGH CALL AS TO HOW FAR SOUTH THE FRONT WILL MOVE...BUT FOR NOW WE WILL KEEP THE BULK OF THE COLD AIR NORTH OF THE AREA THROUGH TONIGHT. SHORT RANGE MODELS ARE OF LITTLE HELP...BUT THE RUC SCENARIO SEEMS PLAUSIBLE IN MOVING THE FRONT INTO THE SOUTHERN PORTION OF THE TEXAS PANHANDLE AROUND 05Z. THE COLD AIR IS SHALLOW PER PROFILERS BEHIND THE BOUNDARY AND THIS COMBINED WITH SOUTHERLY LOW-LEVEL FLOW AHEAD OF THE FRONT WILL HELP TO SLOW THE BOUNDARY/S SOUTHWARD PROGRESS THIS EVENING. FOR OUR AREA...SOUTHERLY FLOW WILL CONTINUE TO TRANSPORT LOW-LEVEL MOISTURE INTO THE LOWER TRANS PECOS AND FAR EASTERN PERMIAN BASIN TONIGHT. WE EXPECT LOW CLOUDS AND/OR FOG...MAINLY AFTER 06Z...GENERALLY EAST OF A SANDERSON TO BIG LAKE LINE. WE HAVE INCREASED CLOUD COVER AND INCLUDED PATCHY FOG FOR THESE AREAS TONIGHT. WE DID NOT INCLUDE LOW CLOUDS IN THE MAF TERMINAL FORECAST YET...BUT THIS WILL NEED TO BE WATCHED CAREFULLY WITH FUTURE ISSUANCES. THE REMAINDER OF THE GRIDS LOOKED GOOD AND ONLY MINOR CHANGES WERE MADE. .LONG TERM... SUCCESSIVE MODEL RUNS CONTINUE TO TAKE SHRTWV TROF CURRENTLY OVR SE CA WELL S OF THE BIG BEND BY THU AFTERNOON. ASSOCIATED FRONT THU AFTERNOON CONTINUES TO LOOK WEAK. TRACK OF THIS TROF LOOKS FAR ENUF S TO ELIMINATE ANY WIND CONCERNS THU AFTERNOON...SAVE FOR WINDY CONDITIONS IN THE GUADALUPES/DELAWARES DURING THE MID AFTERNOON. BRIEF RIDGING ENSUES FRI/SAT...W/LEE SFC DROPPING INTO THE CNTRL PLAINS COURTESY OF NEXT UPSTREAM TROUGH. THIS SHOULD BRING BREEZY CONDITIONS/GOOD DOWNSLOPING ACROSS THE REGION...AND H85 TEMP PROGS SUGGEST TEMP GRIDS NEED FURTHER TRENDING UPWARD. TROF TO ARRIVE LATE SAT/EARLY SUN...FOLLOWED BY FRONT SUN AFTERNOON. GFS STILL INDICATING UPGLIDE SCENARIO SUN AFTERNOON...BUT LOW LVL MSTR RETURN WILL BE POOR GIVEN THU/S INCOMING SHRTWV...AND BEST DYNAMICS N...SO WILL KEEP THINGS DRY. H85 TEMP PROGS SUGGEST COLDER AIR BEHIND SUN/S FRONT WILL HALT JUST N OF THE AREA SUN AFTERNOON... BEFORE DRAINING IN SUN NIGHT/MON MORNING. ACCORDINGLY...HAVE BUMPED UP TEMPS A BIT ON SUNDAY. MONDAY...FLOW BACKS TO ZONAL PATTERN... W/THERMAL RIDGE BUILDING IN TUE/WED FOR A SLOW WARMUP BEFORE GFS BACKDOORS A THIRD COLD FRONT WED NIGHT. && .PRELIMINARY POINT TEMPS/POPS... BIG SPRING TX 35 61 33 60 / 0 0 0 0 CARLSBAD NM 32 61 28 63 / 0 0 0 0 DRYDEN TX 40 64 39 61 / 0 0 0 0 FORT STOCKTON TX 39 64 37 65 / 0 0 0 0 GUADALUPE PASS TX 34 55 39 57 / 0 0 0 0 HOBBS NM 31 59 29 61 / 0 0 0 0 MARFA TX 25 56 26 57 / 0 0 0 0 MIDLAND INTL AIRPORT TX 35 62 34 61 / 0 0 0 0 ODESSA TX 35 62 34 61 / 0 0 0 0 WINK TX 35 65 36 64 / 0 0 0 0 && .MAF WATCHES/WARNINGS/ADVISORIES... TX...NONE. NM...NONE. && $$ 06/44 tx AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE AMARILLO TX 154 PM CST WED JAN 28 2004 .DISCUSSION... AT 19Z THE COLD FRONT WAS QUASI-STATIONARY ACROSS XTRM SRN KS INTO NRN OK...WITH A TEMP IN KGCK OF 18F...OH SO CLOSE. MESO LOW CLEARLY RESOLVED IN THE VARIOUS MESONET OBS...CENTERED NEAR KGUY. OVER THE PAST TWO HRS THE LOW HAS PROPAGATED SWD SLIGHTLY WITH STRONG MIXING ALONG THE LEADING EDGE OF THE DENSITY GRADIENT. AFTER COORDINATING WITH ABQ DDC OUN FTW LUB THE AMA WFO IS FOLLOWING THE MESO-ETA AND FSL RUC-20 REGARDING TONIGHT/S PROGRESSION OF THE FRONT. ATTM THE FRONT IS EXPECTED TO RESUME MOTION FURTHER INTO THE CWA THIS EVENING WITH THE CESSATION OF BL MIXING...REACHING THE I-40 CORRIDOR IN THE 04-07Z TIME FRAME. DUE TO THE VERY SHALLOW DEPTH OF THE AIRMASS AND POSITION OF THE PRESSURE RIDGE...A WEDGE OF COLD AIR SHOULD SURGE FURTHER SOUTH FLOWING DOWN THE LOWER TERRAIN ALONG THE OK BORDER/WRN OK. THE CHALLENGE THEN LIES WITH TOMORROW/S HIGH. THERE COULD BE A LARGE TEMP DIFFERENTIAL ACROSS THE CWA...WARMEST WEST... COLDEST EAST GIVEN ANTICIPATED MIXING. OTHERWISE TEMPS OF FRIDAY APPEAR INTACT FROM THE PREVIOUS PACKAGE. SOME QUESTION ON FROPA TIMING FOR SAT. ADJUSTED TEMPS UP A FRAZ ON SAT BUT WENT A BIT COLDER FOR SUNDAY. LATEST MED-RANGE NWP CONTINUE ENOUGH UNCERTAINTY IN THE WEEKEND S/W TROUGH/UPR LOW TIMING AND PROPAGATION TO MAINTAIN A DRY FCST. THE BEGINNING OF NEXT WEEK SHOULD START OUT CHILLY WITH PERHAPS ANOTHER COLD FRONT TO ARRIVE TUE/WED. $$ AP ALONG W/ GOEHRING && .PRELIMINARY POINT TEMPS/POPS... AMARILLO 16 41 20 55 / 0 0 0 0 BEAVER 2 29 13 40 / 0 0 0 0 BOISE CITY 1 40 14 55 / 0 0 0 0 BORGER 14 38 16 48 / 0 0 0 0 BOYS RANCH 14 41 19 60 / 0 0 0 0 CANYON 22 41 21 57 / 0 0 0 0 CLARENDON 19 35 21 50 / 0 0 0 0 DALHART 13 41 17 58 / 0 0 0 0 GUYMON 1 35 12 44 / 0 0 0 0 HEREFORD 25 42 23 59 / 0 0 0 0 LIPSCOMB 12 30 12 40 / 0 0 0 0 PAMPA 15 35 19 46 / 0 0 0 0 SHAMROCK 18 33 21 42 / 0 0 0 0 WELLINGTON 20 33 21 45 / 0 0 0 0 && .AMA WATCHES/WARNINGS/ADVISORIES... TX...NONE. OK...NONE. && $$ 15/05 tx AREA FORECAST DISCUSSION...1140 AM DISCUSSION... NATIONAL WEATHER SERVICE FORT WORTH TX 1140 AM CST WED JAN 28 2004 .UPDATE... WE ARE VERY BUSY DOING ANALYSES THIS MORNING. SHORT TERM FORECASTER WILL EXAMINE FOR FIRST PERIOD CHANGES DURING THE NEXT HOUR. REGARDING ARCTIC FRONT. CALCULATIONS SHOW IT TO BE MOVING S AT 15 TO 20 KT SOUTHWARD THROUGH NORTHERN OK. THE MOST RECENT RUN OF THE RUC (THE FIRST MODEL TO SHOW THE FASTER/STRONGER PUSH) HAS IT FROM OKC TO CDS BY ABOUT 00Z TONIGHT. WE STILL FEEL THE FRONT WILL MOVE INTO NORTH TEXAS OVERNIGHT. WE ARE TAKING A CLOSE LOOK AT THE TIMING AND WILL BRING CHANGES TO THE AFTERNOON PACKAGE AS NEEDED. /ROBBINS .AVIATION... VFR CONDS EXPECTED THROUGH THE 24 HR TAF CYCLE FOR N TX. SKC-SCT250 WILL PREVAIL THROUGH 06Z THURS...AS SLY FLOW 10-18 KTS THROUGH 00Z THURS...BACKS SEALY AT 5-12 KTS AFTERWARDS. BY 12-15Z THURS...WINDS SHOULD PICK BACK UP SLY 13-20 KTS AS LLJ ENHANCES SOME HIGH BASED STRATO-CU BETWEEN 030-050 FT AND MIXING POTENTIAL. THOUGH THERE/S A POSSIBILITY JUST BEFORE 18Z OF A SHALLOW ARCTIC SURGE AND WINDS BACKING AROUND NELY 10-20 KTS...WILL WAIT UNTIL BETTER CONFIDENCE FOR ANY ADJUSTMENTS ON LATER TAFS. 05/ && .PREV DISCO 357 AM... CHALLENGING FORECAST FOR THE NEXT FEW DAYS AS ARCTIC/POLAR AIR MOVES SOUTHWARD THROUGH THE PLAINS. THE LEADING EDGE OF THE FRONT IS CURRENTLY MOVING THROUGH CENTRAL KANSAS AND EASTERN COLORADO WITH TEMPS DIRECTLY BEHIND IT IN THE SINGLE DIGITS AND SOME VERY COLD TEMPS (NEGATIVE TEENS AND 20S) ACROSS THE NORTHERN PLAINS. THIS COLD AIR IS EXTREMELY SHALLOW AS NOTED BY THE PROFILER DATA AND THE TEMPERATURE TRENDS OF THE EASTERN COLORADO STATIONS IN THE LAST FEW HOURS. THE FIRST ORDER OF CONCERN IS WHEN WILL THIS AIR REACH NORTH TEXAS AND HOW MODIFIED WILL IT BE. ALL THE MODELS...WITH THE EXCEPTION OF THE CANADIAN...HAVE UNDERESTIMATED THE STRENGTH OF THE SURFACE HIGH IN SOUTHERN SASKATCHEWAN THIS MORNING. HOWEVER...00Z ANALYSIS DOES REVEAL A DEVELOPING LEE TROUGH WHICH WILL CAUSE SOME DOWN SLOPE WINDS AND MIXING ON THE WESTERN EDGE OF THE VERY SHALLOW COLD AIR (THIS HAS BEEN HAPPENING ALL MORNING IN EASTERN COLORADO). OUR CURRENT THINKING IS THAT THE MIXING TODAY WILL ERODE AND MODIFY THE LEADING EDGE OF THIS AIR MASS. THEREFORE...WE WILL DELAY FRONTAL PASSAGE UNTIL THURSDAY. FOR NOW WILL STILL GO WELL BELOW GUIDANCE DUE TO A MUCH FASTER FORA TIME. LOOKS LIKE A REINFORCEMENT OF MUCH DEEPER COLD AIR WILL ARRIVE THURSDAY NIGHT...AS STRONG COLD AIR ADVECTION (NOTED ON 00Z 850 ANALYSIS) MOVES INTO THE REGION BEHIND EXITING SHORT WAVE. WILL KEEP TEMPS ON FRIDAY IN THE MID 30S TO THE MID 40S. TEMPS SHOULD BEGIN TO REBOUND SATURDAY...AS A STRONG TROUGH DEVELOPS LEE OF THE ROCKIES AND WINDS TURN TO THE SOUTH. ANOTHER COLD FRONT WILL MOVE INTO NORTH TEXAS ON SUNDAY AND COOL TEMPS INTO THE 40S TO LOWER 50S...EXCEPT FOR MID TO UPPER 50S IN THE EXTREME SOUTH PRIOR TO FORA. DRY AND COOL NORTHWEST FLOW WILL PREVAIL MONDAY AND THURSDAY AND KEEP TEMPS IN THE 40S TO LOWER 50S. FOR NOW...WILL KEEP FORECAST DRY THROUGH DAY 7 AS UPPER LEVEL SUPPORT SHOULD REMAIN WELL NORTH OR JUST SOUTH OF THE REGION. ONLY OUTSIDE CHANCE OF PRECIP WOULD BE IN THE SOUTHERN ZONES THURSDAY NIGHT/FRIDAY...AS A SHORT WAVE SWINGS ACROSS SOUTH TEXAS. IT APPEARS THE TRACK OF THIS SYSTEM WILL BE TOO FAR SOUTH...SO WILL LEAVE 0 POPS. && DALLAS-FT. WORTH, TX 55 31 46 23 / 0 0 0 0 WACO, TX 57 34 49 29 / 0 0 0 0 PARIS, TX 53 32 45 23 / 0 0 0 0 DENTON, TX 55 30 46 22 / 0 0 0 0 MCKINNEY, TX 55 31 46 22 / 0 0 0 0 DALLAS, TX 55 31 46 23 / 0 0 0 0 TERRELL, TX 55 32 46 23 / 0 0 0 0 CORSICANA, TX 56 34 49 26 / 0 0 0 0 TEMPLE, TX 57 37 49 30 / 0 0 0 0 && .FWD WATCHES/WARNINGS/ADVISORIES... TX...NONE. && $$ tx AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GOODLAND KS 217 AM MST THU JAN 29 2004 .DISCUSSION...FORECAST PROBLEMS WILL BE POSITION OF ARCTIC BOUNDARY PLUS THE TIMING OF UPCOMING REINFORCING SURGES. SATELLITE CONTINUING TO SHOW AN AMPLIFIED BUT PROGRESSIVE PATTERN FROM THE CENTRAL PACIFIC INTO NORTH AMERICA. TROUGH APPROACHING THE WEST COAST IS UNORGANIZED BUT IT IS PUMPING UP THE RIDGE ALONG THE COAST. SYSTEM IS MOVING OUT OF SOUTH CENTRAL CANADA INTO THE NORTHERN PLAINS...AND THIS WILL PUSH THE NEXT SURGE INTO THE AREA. VORTEX NEAR EASTERN CANADA IS MOVING BACK CLOSER TO ITS NORMAL HOME AT THE HUDSON BAY. ALL THIS IS KEEPING NORTHWEST FLOW OVER THE AREA. AT 850 MB...THE FRONT IS LOCATED ALONG THE SOUTHERN AND WESTERN EDGES OF THE FORECAST AREA. THE SURFACE LOCATION OF BOUNDARIES IS RATHER COMPLICATED. THE FRONT EXTENDS FROM NORTHWEST OKLAHOMA INTO THE TEXAS PANHANDLE THEN TO A LOW OVER SOUTHEAST COLORADO. THE FRONTAL TROUGH THEN EXTENDS ALONG OUR WESTERN EDGE OF OUR FORECAST AREA THROUGH THE NEBRASKA PANHANDLE INTO A LOW OVER NORTHEAST WYOMING. LEE TROUGH EXTENDS SOUTH OF THIS LOW. SURFACE OBSERVATIONS AND 4 TO 5 MB PRESSURE RISES INDICATE NEXT STRONG PUSH OF COLD AIR IS MOVING THROUGH THE SOUTHERN HALF OF MONTANA. ABOVE THE COLD AIR... THE 700 MB LEVEL IS WARMING TO INCREASE THE INVERSION. AT JET LEVEL...MODELS DID WELL EXCEPT FOR ONE AREA. THIS IS THE JET SEGMENT FROM THE PACIFIC NORTHWEST INTO CALIFORNIA. THE GFS COMPLETELY MISSED THIS SEGMENT WITH THE ETA CATCHING IT. AT MID LEVELS...THE RUC IS DOING THE BEST WITH THE NORTHERN PLAINS SYSTEM COMPARED TO SATELLITE WITH THE GFS SECOND. HOWEVER...THE GFS IS NOT LOW ENOUGH WITH HEIGHTS WITH THIS SYSTEM WITH THE ETA MUCH BETTER. THE GFS IS DOING BETTER WITH THE HEIGHTS FROM THE DESERT SOUTHWEST TO ALONG THE WEST COAST. THE GFS ONCE AGAIN IS TOO PROGRESSIVE AND NOT AMPLIFIED ENOUGH WITH THE FLOW OVER THE PACIFIC. AT LOW LEVELS...THE ETA IS HANDLING THE LOW LEVEL/850 MB TEMPERATURES THE BEST AS ONE WOULD EXPECT. BUT BASED ON THE LBF AND UNR SOUNDINGS...IT ONCE AGAIN DOES NOT HAVE THE COLD AIR FAR ENOUGH SOUTH AND WEST. FROM THE NORTHERN PLAINS INTO CANADA...THE ETA IS DOING VERY WELL. THE ETA AND RUC ARE DOING THE BEST WITH THE WIND FIELD. LIKE THE SLOWER PROGRESSION OF THE ETA WITH THE NEXT TROUGH. THE GFS IS TOO PROGRESSIVE. WILL PRETTY MUCH GO WITH A BLEND OF THE ETA...RUC...AND PERSISTANCE FOR THIS PACKAGE. FOR TODAY/TONIGHT...HOW FAR EAST DOES THE COLD AIR RETREAT BEFORE THE NEXT SURGE COMES IN. THE RUC/ETA HAVE THE WINDS SHIFTING TO THE NORTH BY 15Z. THEN AS YESTERDAY...THE WINDS SWING AROUND TO THE SOUTH BY LATE AFTERNOON. TO COMPLICATE THINGS...HAVE A LOT OF MID AND HIGH LEVEL CLOUD COVER TO MOVE THROUGH. THE RUC 20 AND 40 KM DID BEST WITH THE CLOUDS...WINDS...AND TEMPERATURES YESTERDAY FOLLOWED BY THE ETA. PLAN ON FOLLOWING THE COOLEST GUIDANCE...ESPECIALLY IN THE EAST. BY THE END OF THE DAY GET IN STRONG SUBSIDENCE FROM THE JET AS UPPER RIDGE PUSHES INTO THE AREA. DOWNSLOPE WINDS SURGE FURTHER WEST TONIGHT...AND MAKE IT ALMOST TO THE EASTERN END OF THE FORECAST AREA. MODELS INDICATE SIGNIFICANT WARMING OVERNIGHT...ESPECIALLY AFTER 06Z. WILL FOLLOW GUIDANCE CLOSELY...NEAR TO ABOVE WEST TO BELOW EAST. FOR FRIDAY/FRIDAY NIGHT...THE WINDS START OUT DOWNSLOPE...AND THEN SHIFT TO THE SOUTH AND SOUTHEAST WITH THE EASTERN LOCATIONS OF OUR AREA SEEING THE LEAST FAVORABLE PROFILE. WILL HAVE AN EXTREMELY TIGHT GRADIENT WITH 50S PROBABLE ALONG THE KANSAS AND COLORADO BORDER AND MUCH COOLER IN THE EAST. MAY RAISE MAXES SOME BUT WILL STAY BELOW GUIDANCE. EAST TO SOUTHEAST WINDS LOOK TO USHER IN STRATUS DURING THE NIGHT PER THE ETA BOUNDARY LAYER FORECASTS. THE EASTERN HALF LOOKS TO GET THE BRUNT OF THIS...BUT MAY GET AS FAR AS THE KANSAS AND COLORADO BORDER BY LATE IN THE NIGHT. SINCE GUIDANCE TOO WARM...PLAN ON GOING NEAR TO SLIGHTLY BELOW GUIDANCE. FOR SATURDAY/SATURDAY NIGHT...STRATUS AND COLD AIR ADVECTION LOOK TO KEEP TEMPERATURES FROM RISING TOO MUCH. PLAN ON GOING WITH THE COOLEST GUIDANCE...ESPECIALLY IN THE EAST. NO CHANGES PLANNED IN THE 4 TO 7 DAY PERIOD AT THIS TIME. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ BULLER ks AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 352 AM EST THU JAN 29 2004 .DISCUSSION... STRONG SURFACE HIGH PRESSURE OVER SASKATCHEWAN HAS BROUGHT ANOTHER ROUND OF ARCTIC AIR TO THE REGION. 08Z OBSERVATIONS SHOW TEMPERATURES ALREADY APPROACHING THE 0C F MARK ACROSS THE NORTHERN PORTIONS OF THE FORECAST AREA. ELONGATED UPPER LOW PRESSURE OVER EASTERN ONTARIO WILL ADVANCE INTO NEW ENGLAND TODAY...HELPING TO CARVE OUT A DEEP UPPER LOW OVER QUEBEC AND MAINTAINING NORTHWESTERLY FLOW ALOFT OVER THE REGION THROUGH THE END OF THE WEEK. LAKE EFFECT SNOWFALL AND TEMPERATURES WILL BE THE MAIN FORECAST CONCERNS THE NEXT FEW DAYS AS THIS ARCTIC AIR RESIDES OVER THE REGION. AN UPPER LEVEL JET MAX PARKED OVER LOWER MICHIGAN IS HELPING TO DEVELOP SOME LIFT ALONG THE 850MB FRONT OVER THE UPPER MIDWEST...LEADING TO SOME SNOW ACROSS SOUTH DAKOTA AND AN AREA OF MID CLOUDS WHICH EXTENDS INTO NW INDIANA. THIS AREA OF LIFT WILL PASS JUST SOUTH OF THE STATE THIS AFTERNOON. THE WATER VAPOR LOOP DOES HOWEVER SHOW A SHORT WAVE OVER NORTH DAKOTA. MODELS GENERALLY INDICATE THIS WAVE WILL MOVE INTO SOUTHERN WISCONSIN BY 18Z...WEAKENING AS IT ENCOUNTERS SOME CONFLUENT FLOW ALOFT OVER THE GREAT LAKES. THE GFS AND RUC SOLUTIONS ARE A BIT SLOWER AND STRONGER WITH THIS WAVE AND ACTUALLY BRING IT ACROSS SOUTHERN LOWER MICHIGAN THIS EVENING. STILL NOT EXPECTING MUCH LIFT WITH THE WAVE...BUT IT WILL BE ENOUGH TO RAISE INVERSION HEIGHTS OVER SOUTHERN LAKE MICHIGAN. BETWEEN 18Z AND 21Z...EQUILIBRIUM LEVELS RISE TO 5500FT PER ETA SOUNDINGS WITH HIGH MOISTURE EXTENDING TO 700MB. THUS EXPECT SOME LAKE ENHANCEMENTS THIS AFTERNOON/EVENING. MESO ETA INDICATES THE BOUNDARY LAYER FLOW WILL BE MORE NORTHWESTERLY...THUS LAKE EFFECTS WOULD NOT HAVE MUCH IMPACT ON SE LOWER MI. HOWEVER...FEEL THE MODEL IS UNDERESTIMATING THE STRENGTH OF THE SHORT WAVE A LITTLE AND THAT THE WINDS MAY BACK MORE WESTERLY OVER THE LAKE FOR A TIME...SUGGESTING SOME BETTER CONVERGENCE ALONG THE I-94 CORRIDOR. SURFACE WINDS OVER NE INDIANA AND NW OHIO ARE ALREADY MORE SOUTWESTERLY THAN INDICATED BY MODELS. WILL THUS INCREASE POPS ACROSS THE FAR SOUTH BUT KEEP ACCUMULATIONS MINIMAL AT THIS TIME. WILL TREND POPS BACK TO LOW CHANCE ACROSS THE SAGINAW VALLEY AS MOISTURE BECOMES MORE LIMITED. AS SOME WEAK SUBSIDENCE PUSHES ACROSS THE REGION OVERNIGHT...SHOULD DRASTICALLY SEE A REDUCTION IN LAKE EFFECT ACTIVITY...ESPECIALLY GIVEN THE EXTREMELY DRY BOUNDARY LAYER THAT WILL BE ADVECTING INTO THE LAKE FROM WISCONSIN. THE FLOW SHOULD BECOME MORE NORTHWESTERLY OVERNIGHT AND FOCUS ANY FLURRY ACTIVITY TO THE FAR SOUTH. THIS WILL ALSO ALLOW MUCH OF THE NORTHERN PORTIONS OF THE FORECAST AREA TO BREAK OUT OF THE CLOUDS...THUS SUB ZERO LOW TEMPS LOOK POSSIBLE. THIS WILL DEPEND HEAVILY ON HOW MUCH THE WINDS WILL BE ABLE TO DIMINISH. ANOTHER SHORT WAVE WILL SWING THROUGH THE REGION ON FRIDAY. NOT MUCH MOISTURE AVAILABLE WITH THIS FEATURE...BUT LIKELY ENOUGH TO ENHANCE THE LAKE EFFECT ACTIVITY. THE ETA AND GFS ARE SHOWING HIGH PRESSURE NUDGING INTO ILLINOIS AND CENTRAL INDIANA ON FRIDAY. THIS SETUP SHOULD BE IDEAL FOR GETTING SOME DOMINATE CONVERGENCE BANDS TO DEVELOP OFF LAKE MICHIGAN...SOMEWHERE BETWEEN I-94 AND I-69. WILL ADD A CHANCE OF SNOW SHOWERS IN THIS AREA TO ACCOUNT FOR THIS AND MAINTAIN FLURRIES ELSEWHERE. WILL GENERALLY SIDE A COUPLE DEGREES BELOW GUIDANCE THROUGH FRIDAY NIGHT GIVEN THE EXTENSIVE SNOWPACK ACROSS THE REGION. RIDGING ALOFT WILL THEN BUILD INTO THE REGION SATURDAY AS THE ARCTIC AIR RETREATS TO THE NORTHEAST...ALLOWING A BIT OF A WARMUP. MODEL SOLUTIONS DIVERGE ON THEIR TIMING OF THE NEXT WAVE TO MOVE INTO THE UPPER MIDWEST ON SUNDAY. NONETHELESS...GIVEN THE EASTERLY SURFACE TRAJECTORIES AROUND THE SURFACE HIGH TO THE EAST...FEEL THE GFS IS OVERDONE WITH QPF. WILL THUS STEER THE FORECAST TOWARD THE DRYER ETA SOLUTION AND BACK OFF ON POPS. THE GFS...ETA AND EUROPEAN SOLUTIONS ARE SHOWING A SOUTHERN STREAM WAVE DROPPING INTO NEW MEXICO ON SUNDAY...WITH A DEVELOPING SURFACE LOW PRESSURE OVER TEXAS. THE GFS SOLUTION INDICATES THIS SURFACE LOW WILL MOVE INTO OHIO ON MONDAY. THIS TRACK TARGETS SE MICHIGAN FOR POTENTIAL WARNING CRITERIA SNOWFALL. GIVEN THERE IS SOME SEMBLANCE OF AGREEMENT WITH THE EUROPEAN SOLUTIONS OF A LOW MOVING INTO THE OHIO VALLEY...WILL ADDRESS THIS SYSTEM IN THE HAZARDOUS WEATHER OUTLOOK. SINCE IT IS STILL VERY EARLY IN THE FORECAST...A LOT CAN CHANGE IN THE PROJECTED STRENGTH...TIMING AND LOCATION OF THIS LOW. && .DTX WATCHES/WARNINGS/ADVISORIES...GALE WARNING...THIS MORNING...LAKE HURON. && $$ CONSIDINE EXPERIMENTAL GRAPHICAL FORECASTS ARE AVAILABLE ONLINE AT HTTP://WWW.CRH.NOAA.GOV/DTX (ALL LOWER CASE) mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BUFFALO NY 320 AM EST THU JAN 29 2004 BELOW NORMAL TEMPERATURES AND FREQUENT BOUTS OF SNOW WILL PERSIST ACROSS WESTERN AND NORTH CENTRAL NEW YORK INTO THE UPCOMING WEEKEND AS BRISK WEST TO NORTHWEST WINDS WILL CONTINUE TO FEED ARCTIC AIR INTO THE REGION. A POTENT UPPER LEVEL SHORTWAVE JUST NORTH OF YYZ AT 07Z WILL RACE EAST AND CROSS NEW ENGLAND TODAY...WHILE A STRONG WESTERLY SFC FLOW IN ITS WAKE WILL CONTINUE TO BLOW AND DRIFT NEW FALLEN SNOW. THERE WILL BE SOME LAKE EFFECT SNOW TO DEAL WITH AS WELL...BUT A FROZEN GEORGIAN BAY AND LAKE ERIE WILL LIMIT THE ACTIVITY IN THE WEST. MEANWHILE A MAJOR LAKE EFFECT SNOW WILL CONTINUE EAST OF LK ONTARIO. A GENERAL 270-290 FLOW OF -20 H8 AIR...COUPLED WITH A CAP OF 6-7K DEEP AND A FAVORABLE OMEGA FIELD...WILL KEEP AN IMPRESSIVE PLUME OF LAKE SNOW IN PLACE OVER OSWEGO COUNTY AND SRN LEWIS COUNTY. ETA12 SFC WIND FIELDS IMPLY STRONG LL CONVERGENCE...AND THIS ALONG WITH 00Z RUN OF WRKSTN ETA HAVE BEEN HANDLING OVERNIGHT ACTIVITY VERY WELL. FEEL THAT CONTINUITY LOOKS VERY GOOD WITH THE PLACEMENT OF THIS ACTIVITY...WHICH JUST SO HAPPENS TO BE SUPPORTED BY WRKSTN ETA AND ETA12 SFC WIND FIELD. RUC10 SEEMS TO HAVE THE BAND TOO FAR SOUTH TODAY...AND HAS BEEN TOO FAR SOUTH ON OTHER RECENT EVENTS. SNOWFALL OF 6 TO 12 INCHES ARE EXPECTED OVER OSWEGO AND SRN LEWIS COUNTIES TODAY...WITH ANOTHER 6 TO 12 EXPECTED TONIGHT. RUNNING SNOW TOTALS THROUGH THURSDAY MORNING SHOULD BE IN THE NEIGHBORHOOD OF 2 FEET IN SOME SPOTS. A CONTINUED WESTERLY FLOW OF VERY COLD AIR WILL LIKELY KEEP THIS SNOWBAND IN PLACE THROUGH FRIDAY AND FRIDAY NIGHT... BUT SUBTLE WIND CHANGES COULD SHIFT THE SNOW A LITTLE FURTHER NORTH TO AREAS WHERE PREVIOUS LAKE SNOWS HAVE YET TO FALL. WILL THUS EXTEND THE CURRENT LAKE SNOW WARNING THROUGH FRIDAY. TOTALS OF 3 FEET OR MORE WILL CERTAINLY BE POSSIBLE BY THE WEEKEND. LAKE SNOW ADVISORY FOR NRN CAYUGA CO WILL BE LEFT IN PLACE TODAY DUE TO THE CHANCE FOR THE BAND TO SHIFT A BIT FURTHER SOUTH (AS PER RUC). FOR LK ERIE ACTIVITY...WILL EXTEND LES ADVISORY UNTIL MIDDAY TODAY TO ACCOUNT FOR WEAK ACTIVITY CURRENTLY UNDERWAY. A PROGRESSIVE RIDGE WILL MOVE TO THE EAST ACROSS THE GREAT LAKES DURING THE WEEKEND....BRINGING AN END TO THE LAKE EFFECT ACTIVITY WHILE ALSO RAISING OUR TEMPS. SHOULD THE MRF VERIFY...TEMPS FOR MOST SITES COULD FINALLY CLIMB ABV FEEEZING ON MONDAY WITH THE CHANCE FOR A MIX OF RAIN AND/OR SNOW. AVIATION DISCUSSION... CONDITIONS HAVE IMPROVED TO MVFR AT KBUF-KIAG-KROC AS SYNOPTIC SNOW ENDED. LAKE EFFECT SNOWS CONTINUE SOUTH OF KIAG/KBUF THOUGH END OF SNOWBAND OCCASIONALLY EDGES INTO KROC. MVFR CONDTIONS PRIMARILY DUE TO THE LOWERED VSBY IN BLOWING SNOW. EXPECT LITTLE CHANGE IN THESE CONDITIONS OVER TODAY. NO KART TAF DUE TO LACK OF OBS...LAKE EFFECT SQUALL OFF ONTARIO NOW SOUTH OF THERE IS EXPECTED TO LIFT NORTH ACROSS TOWARD KART BETWEEN 08Z AND 10Z, THEN SETTLE BACK SOUTH BETWEEN KART AND KSYR (NEAR KFZY) FOR THE REST TODAY AND TONIGHT. .BUF...LAKE EFFECT SNOW ADVISORY UNTIL 12 NOON NYZ019-020. LAKE EFFECT SNOW ADVISORY TODAY NYZ005. LAKE EFFECT SNOW WARNING TODAY THROUGH FRIDAY NYZ006-008. $$ RSH AVIATION DISCO...JML= ny AREA FORECAST DISCUSSION UPDATED NATIONAL WEATHER SERVICE BUFFALO NY 931 AM EST THU JAN 29 2004 LAKE BAND OVER LAKE ONTARIO POUNDING SOUTHERN OSWEWGO COUNTY. REPORTS OF 3 TO 5 INCHES AND HOUR FALLING IN THE FULTON WEST MONROE AREAS. PROFILES SHOW BAND MAY LIFT A BIT NORTH THIS AFTERNOON BUT STILL BE OVER OSWEGO COUNTY. WILL MENTION ADDITIONAL AMNTS OF 1 TO 2 FEET IN SPOTS THIS AFTERNOON. BAND ALSO HITTING NORTHERN CAY COUNTY NR THE LAKE. WILL ISSUE WARNING THERE WITH ACCUMS OF 5 TO 10 INCHES WITH HIGHEST AMNTS NR THE LAKE. ALSO MENTION THAT BAND MAY MOVE A BIT NORTH DURING THE AFTN. ALSO MENTIONING UP TO 4 INCHES POSSIBLE OVER NORTHEASTERN WAYNE COUNTY. WEAKER LAKE EFFECT EAST OF MOSTLY FROZEN LAKE ERIE BUT MM5 SHOWS ACTIVITY PERSISTING OVER NORTHERN CHAU/CATT COUNTIES. GOING WITH ACCUMULATIONS OF 2-4 INCHES AND WITH 10-20 MPH WINDS WITH HIGHER GUSTS CREATING POOR VSBYS AT TIMES WE WILL KEEP LAKE EFFECT SNOW ADVSRY GOING THROUGH THE AFTERNOON. NO CHANGES TO LATER PERIODS OF THE FORECAST. EARLIER AFD FOLLOWS... JJP BELOW NORMAL TEMPERATURES AND FREQUENT BOUTS OF SNOW WILL PERSIST ACROSS WESTERN AND NORTH CENTRAL NEW YORK INTO THE UPCOMING WEEKEND AS BRISK WEST TO NORTHWEST WINDS WILL CONTINUE TO FEED ARCTIC AIR INTO THE REGION. A POTENT UPPER LEVEL SHORTWAVE JUST NORTH OF YYZ AT 07Z WILL RACE EAST AND CROSS NEW ENGLAND TODAY...WHILE A STRONG WESTERLY SFC FLOW IN ITS WAKE WILL CONTINUE TO BLOW AND DRIFT NEW FALLEN SNOW. THERE WILL BE SOME LAKE EFFECT SNOW TO DEAL WITH AS WELL...BUT A FROZEN GEORGIAN BAY AND LAKE ERIE WILL LIMIT THE ACTIVITY IN THE WEST. MEANWHILE A MAJOR LAKE EFFECT SNOW WILL CONTINUE EAST OF LK ONTARIO. A GENERAL 270-290 FLOW OF -20 H8 AIR...COUPLED WITH A CAP OF 6-7K DEEP AND A FAVORABLE OMEGA FIELD...WILL KEEP AN IMPRESSIVE PLUME OF LAKE SNOW IN PLACE OVER OSWEGO COUNTY AND SRN LEWIS COUNTY. ETA12 SFC WIND FIELDS IMPLY STRONG LL CONVERGENCE...AND THIS ALONG WITH 00Z RUN OF WRKSTN ETA HAVE BEEN HANDLING OVERNIGHT ACTIVITY VERY WELL. FEEL THAT CONTINUITY LOOKS VERY GOOD WITH THE PLACEMENT OF THIS ACTIVITY...WHICH JUST SO HAPPENS TO BE SUPPORTED BY WRKSTN ETA AND ETA12 SFC WIND FIELD. RUC10 SEEMS TO HAVE THE BAND TOO FAR SOUTH TODAY...AND HAS BEEN TOO FAR SOUTH ON OTHER RECENT EVENTS. SNOWFALL OF 6 TO 12 INCHES ARE EXPECTED OVER OSWEGO AND SRN LEWIS COUNTIES TODAY...WITH ANOTHER 6 TO 12 EXPECTED TONIGHT. RUNNING SNOW TOTALS THROUGH THURSDAY MORNING SHOULD BE IN THE NEIGHBORHOOD OF 2 FEET IN SOME SPOTS. A CONTINUED WESTERLY FLOW OF VERY COLD AIR WILL LIKELY KEEP THIS SNOWBAND IN PLACE THROUGH FRIDAY AND FRIDAY NIGHT... BUT SUBTLE WIND CHANGES COULD SHIFT THE SNOW A LITTLE FURTHER NORTH TO AREAS WHERE PREVIOUS LAKE SNOWS HAVE YET TO FALL. WILL THUS EXTEND THE CURRENT LAKE SNOW WARNING THROUGH FRIDAY. TOTALS OF 3 FEET OR MORE WILL CERTAINLY BE POSSIBLE BY THE WEEKEND. LAKE SNOW ADVISORY FOR NRN CAYUGA CO WILL BE LEFT IN PLACE TODAY DUE TO THE CHANCE FOR THE BAND TO SHIFT A BIT FURTHER SOUTH (AS PER RUC). FOR LK ERIE ACTIVITY...WILL EXTEND LES ADVISORY UNTIL MIDDAY TODAY TO ACCOUNT FOR WEAK ACTIVITY CURRENTLY UNDERWAY. A PROGRESSIVE RIDGE WILL MOVE TO THE EAST ACROSS THE GREAT LAKES DURING THE WEEKEND....BRINGING AN END TO THE LAKE EFFECT ACTIVITY WHILE ALSO RAISING OUR TEMPS. SHOULD THE MRF VERIFY...TEMPS FOR MOST SITES COULD FINALLY CLIMB ABV FEEEZING ON MONDAY WITH THE CHANCE FOR A MIX OF RAIN AND/OR SNOW. AVIATION DISCUSSION... CONDITIONS HAVE IMPROVED TO MVFR AT KBUF-KIAG-KROC AS SYNOPTIC SNOW ENDED. LAKE EFFECT SNOWS CONTINUE SOUTH OF KIAG/KBUF THOUGH END OF SNOWBAND OCCASIONALLY EDGES INTO KROC. MVFR CONDTIONS PRIMARILY DUE TO THE LOWERED VSBY IN BLOWING SNOW. EXPECT LITTLE CHANGE IN THESE CONDITIONS OVER TODAY. NO KART TAF DUE TO LACK OF OBS...LAKE EFFECT SQUALL OFF ONTARIO NOW SOUTH OF THERE IS EXPECTED TO LIFT NORTH ACROSS TOWARD KART BETWEEN 08Z AND 10Z, THEN SETTLE BACK SOUTH BETWEEN KART AND KSYR (NEAR KFZY) FOR THE REST TODAY AND TONIGHT. .BUF...LAKE EFFECT SNOW ADVISORY THIS AFTERNOON NYZ019-020. LAKE EFFECT SNOW WARNING THIS AFTERNOON NYZ005. LAKE EFFECT SNOW WARNING TODAY THROUGH FRIDAY NYZ006-008. $$ JJP/RH AVIATION DISCO...JML= ny EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION NATIONAL WEATHER SERVICE TULSA OKLAHOMA 1025 AM CST THU JAN 29 2004 ARCTIC FRONT LYING VERY CLOSE TO I-44 CORRIDOR AT PRESENT...JUST A TAD FARTHER SOUTH THAN MESO ETA INITIALIZATION. FRONT CONTINUES TO MAKE V E R Y SLOW PROGRESS SOUTH (APPEARS TO HAVE FINALLY CROSSED THE EASTBOUND LANE IN THE PAST HOUR) AND LIKE YESTERDAY...AT LEAST RIGHT NOW...BEING DRIVEN SOUTH ON DENSITY ALONE. HOWEVER A COUPLE OF IMPORTANT DIFFERENCES TODAY. FIRST...CONSIDERABLE CLOUD COVER WILL LIMIT PREFRONTAL MIXING AND ALLOW THE COLD AIR TO MAKE A BETTER PUSH ON ITS OWN. SECOND A CLIPPER SYSTEM PUSHING THROUGH THE NORTHERN PLAINS THIS MORNING WILL FINALLY PROVIDE SOME UPPER SUPPORT TO HELP DRIVE THE FRONT SOUTH LATER TODAY AS MESO ETA/RUC DEPICT. THIS IS REFLECTED AT THE SFC BY AREA OF 4-5MB 3 HOUR PRESSURE RISES OVER WESTERN NEBRASKA WHICH WILL CONTINUE TO TRANSLATE TO THE SOUTH. DUE TO THE VERY SHALLOW NATURE OF THIS AIRMASS...500 METER PROFILER WINDS OVER CENTRAL KS STILL OUT OF THE WSW THIS MORNING...IT WILL HAVE A TOUGH TIME CLEARING THE OZARK PLATEAU AND THE OUCHITAS. OTHERWISE THE FRONT SHOULD CLEAR THE MAJORITY OF THE FORECAST AREA BY 06Z. HAVE SENT AN UPDATE BUT OVERALL CHANGES TO THE FORECAST PRETTY MINIMAL. INCREASED CLOUD COVER ACROSS THE BOARD. ALSO LOWERED HIGHS NORTH OF THE FRONT TO JUST A FEW DEGREES ABOVE CURRENT READINGS... AND RAISED A FEW DEGREES TO THE SOUTH AS MANY SITES NEAR FORECAST HIGHS AND WILL CLIMB A LITTLE MORE BEFORE FRONT FINALLY PUSHES THROUGH. FORECAST ID= 14 .TSA WATCHES/WARNINGS/ADVISORIES... AR...NONE. OK...NONE. $$ SULLIVAN ok AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE PITTSBURGH PA 1040 AM EST THU JAN 29 2004 MADE UPDATE TO INCLUDE MENTION OF SNOW AMOUNTS...UP TO 3 INCHES IN THE MORE GEOMORPHOLOGICALLY-INFLUENCED CHEAT MOUNTAINS...AS RADAR AND SURFACE DATA SHOWS FRONTOGENETICALLY-INDUCED SNOW BAND SETTING UP FROM NORTHERN INDIANA INTO THAT REGION. RUC AND ETA SHOW THIS PHENOMENA LASTING INTO THE EVENING. OTHER WEAKER BANDS ALSO SETTING UP FARTHER NORTH ACROSS THE REMAINDER OF THE UPPER OHIO VALLEY. REST UNCHANGED. LATEST GFS ECMWF AND UKMET STILL SHOW A STORMY PATTERN SETTING UP FOR NEXT WEEK. ...GIORDANO .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...NONE. WV...NONE. && $$ pa AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE GOODLAND KS 1120 AM MST THU JAN 29 2004 .DISCUSSION...AGAIN THE PRIMARY CONCERN FOR THE FIRST PERIOD IS TEMPERATURES AS THE GLD FORECAST AREA HAS A TEMPERATURE GRADIENT OF 40 DEGREES FROM WEST TO EAST. AT 18Z TEMPERATURES RANGE FROM 45 IN FLAGLER TO 5 IN ALMENA (NORTHEAST NORTON COUNTY). HAVE WAITED TO SEE HOW THINGS SHAKE OUT AS INCREASED NORTH WINDS BROUGHT THE TEMPS UP QUITE A BIT EARLIER THIS MORNING BUT NOW APPEAR TO HAVE STABILIZED. BASED ON 18Z FORECAST FROM THE ETA AND RUC I HAVE UPDATED GRIDS BASICALLY USING THE RUC OVER THE EASTERN HALF AND THE ETA OVER THE WESTERN HALF. FORECAST WAS IN PRETTY GOOD SHAPE WITH THE BIGGEST CHANGES GENERALLY OVER THE CENTRAL ZONES WHERE THE TWO MODELS KIND OF COMPROMISED ON THE TEMPS. OTHER UPDATES FOR THE FIRST PERIOD WERE FOR THE CLOUDS...DEWPOINTS...AND WINDS. STRATUS IS COMING IN FROM THE NORTH AND NORTHEAST WHILE MID LEVEL CLOUDS ARE COMING IN FROM THE NORTHWEST. HAVE TWEAKED THE CLOUDS A BIT BUT A GENERAL PARTLY OR MOSTLY CLOUDY LOOKS GOOD. THATS IT FOR NOW. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ DDT ks AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 200 PM EST THU JAN 29 2004 .DISCUSSION... VISIBLE AND WATER VAPOR LOOPS SHOW FIRST IN A SERIES OF UPPER WAVES MOVING INTO SOUTHWEST WISCONSIN AND HEADING TOWARD FAR SOUTHERN LAKE MICHIGAN AND THE NORTHERN OHIO VALLEY. NOT MUCH MOISTURE WITH THIS SYSTEM...HOWEVER 40KM RUC SHOWING SOME MODEST 850-700 MB Q-VECTOR CONVERGENCE WITH THIS WAVE AS IT MOVES ACROSS SOUTHEAST LOWER THIS EVENING. BRIEF INCREASE IN VERSION HEIGHTS TO AROUND 4K AND INCREASE IN 700 MB MOISTURE. 40KM RUC ALSO SHOWING A VERY SHARP 850-700 MB MOISTURE GRADIENT ACROSS SOUTHEAST LOWER THIS EVENING. THUS WILL HAVE A DRY FCST FOR THE SAGINAW VALLEY...FLURRIES FOR THE GENESEE VALLEY...SCT SW FOR PTK AREA AND LIKELY FOR DTW AND POINTS SOUTH...IN REGION OF BETTER LOW LEVEL CONVERGENCE. TEMPERATURES SHOULD NOT PLUNGE BELOW ZERO ACROSS THE NORTHERN CWA WITH SFC GRADIENT SO STRONG...AND SOME LAKE CLOUDS FILTER IN THROUGH THE NIGHT. ETA/GFS IN GOOD AGREEMENT OVER THE GREAT LAKES REGION THROUGH 84 HOURS. INVERSION HEIGHTS LOWERING RAPIDLY ON FRIDAY...TO AROUND 2K BY 18Z...SECOND UPPER WAVE TO AFFECT THE LOWER GREAT LAKES AROUND 12Z WILL HAVE EVEN LESS MOISTURE TO WORK WITH...THUS WILL CONTINUE WITH SCT POPS ACROSS THE CENTRAL PORTION OF THE CWA...FLURRIES ELSEWHERE. PERSISTENT CYCLONIC FLOW FRIDAY AFTERNOON THROUGH SATURDAY MORNING AND SOME INSTABILITY OVER LAKE MICHIGAN...THUS WILL CONTINUE WITH FLURRIES THROUGH THAT PERIOD. NEXT CONCERN WILL BE FOR LATE SATURDAY NIGHT AND SUNDAY...IN REGION OF PERSISTENT WEAK ISENTROPIC LIFT...AFTER LOOKING AT THE 290K SURFACE BELIEVE MORE AGGRESSIVE GFS IS BETTER...DUE TO PERSISTENT 35KT CROSS ISOBARIC...THUS WILL CONTINUE WITH CHC POPS FOR LIGHT SNOW. FINAL CONCERN IS FOR STORM LATE SUNDAY NIGHT INTO MONDAY. PURE ISENTROPIC SOLUTIONS WOULD SUGGEST UP TO 8 INCHES OF SNOW...THEN A COUPLE MORE INCHES BEFORE SYSTEM REDEVELOPS ALONG THE ATLANTIC SEABOARD. SOME CONCERN ABOUT CONVECTION FIRING OVER THE TENNESSEE VALLEY AND INTERCEPTING SOME OF THIS MOISTURE...IN REGION OF GOOD THICKNESS DIFFLUENCE...AND 850 MB MOISTURE TRANSPORT INTO AREA OF MODEST INSTABILITY. MIXED PCPN ALSO POSSIBLE AS FAR NORTH AS PTK...MUCH LIKE THE LAST SYSTEM. WILL HIGHLIGHT SIGNIFICANT SNOW POTENTIAL IN HWO AT THIS TIME. && .DTX WATCHES/WARNINGS/ADVISORIES...NONE. && $$ GSS EXPERIMENTAL GRAPHICAL FORECASTS ARE AVAILABLE ONLINE AT HTTP://WWW.CRH.NOAA.GOV/DTX (ALL LOWER CASE) mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 1130 AM EST THU JAN 29 2004 .SHORT TERM... MAIN FCST CONCERNS THIS AFTERNOON ARE LES TRENDS AND WIND CHILLS. WV IMAGERY AND RUC ANALYSIS INDICATED NW FLOW THROUGH THE NRN CONUS ON SRN PERIPHERY ELONGATED TROF FROM CNTRL CANADA TO NEW ENGLAND BENEATH HIGH LATITUDE RDG OVER NE CANADA / GREENLAND. LITTLE IN THE WAY OF SIGNIFICANT SHRTWVS UPSTREAM WITH MAIN BAROCLINIC ZONE TO THE SOUTH. AT THE SFC...300-320 CBL FLOW PERSISTED DOWNSTREAM OF 1040 MB ARCTIC RDG FROM CNTRL CANADA INTO THE ERN PLAINS. 12Z UPSTREAM SNDGS SHOWED TYPICAL ARCTIC AIRMASS PRFL...NEARLY ISOTHERMAL (AROUND -21 TO -26C) TO 700 MB. RADAR AND VIS LOOP INDICATED -SHSN MAINH FROM THE PORCUPINES NE THROUGH THE KEWEENAW AND FOR LOCATIONS IN THE EAST FROM MUNISING EASTWARD. WITH TEMPS CLIMBING TO AROUND 0F OVER CNTRL UPR MI...WIND CHILLS HAVE MODERATED WITH VALUES MAINLY -10 TO -20. OVER THE SW...TEMPS IN THE -5 TO -15 F RANGE WITH 10 TO 15 MPH HAS KEPT WC VALUES FROM -25 TO -35. EXPECT LES RATES/LOCATION TO CHANGE LITTLE THIS AFTERNOON. THIS WOULD KEEP 1-2 INCH AMOUNTS OVER THE WEST AND UP TO 3 INCHES OVER THE NE CWA. SUNSHINE AND SFC WARMING EXPECTED OVER THE REST OF UPR MI WILL BRING ENOUGH MODERATION IN TEMPS/WCHILL TO DROP ADVISORIES FOR THIS AFTERNOON...EXCEPT OVER THE WEST (VCNTY IWD) WHICH IS IN CLOSER PROXIMITY TO CORE OF THE COLDEST AIR. JLB .PREV DISCUSSION... TONIGHT INTO FRI NIGHT...CLIPPER SHRTWV FROM MANITOBA SLIDES SOUTH OF REGION TONIGHT PROVIDING PERIOD OF BRIEF ENHANCEMENT FOR MORE INTENSE LES BANDS. A SECOND SHRTWV LOBE ROTATING SEWD FROM QUEBEC AND ONTARIO LATE FRI INTO FRIDAY NIGHT WILL BRING DEEP MOISTURE OVER AREA (EVIDENT ON 00Z CWPL SNDG) AND BEGIN TO WARM 850 MB TEMPS TO -14C TO -18C OVER LAKE SUPERIOR. ASSOC ISENTROPIC ASCENT AND MORE FAVORABLE SNOW GROWTH SHOULD AID IN DVLPMT OF CONTINUED INTENSE LES BANDS ESPECIALLY OVER ERN LAKE SUPERIOR IN STRENGTHENING NW FLOW. THUS...HAVE DECIDED TO CONTINUE WINTER STORM WARNING FOR ALGER-LUCE COUNTIES TONIGHT INTO FRI NIGHT FOR 3-7 INCH AMTS EACH PD. LLVL CONVERGENCE WILL NOT FAVOR NRN SCHOOLCRAFT FOR FOCUSING BEST BANDS THERE BUT THEY SHOULD STILL GET ADVISORY AMTS EACH PD (2-5 INCHES) WITH PLENTY OF BLOWING SNOW AS WINDS SHOULD BE 15-25 MPH. OVER WEST WILL ALSO CONTINUE WINTER WX ADVISORY TONIGHT THROUGH FRIDAY FOR ADDITIONAL ACCUMS OF 2-4" (1-3" KEW WHERE FETCH WILL BE SHORTENED IN NW FLOW). WINDS CHILLS WILL CONTINUE QUITE COLD ESPECIALLY TONIGHT INTO FRIDAY (15 TO 35 BELOW RANGE AGAIN) AS ACTUALLY LOWS FALL TO 10 TO 20 BELOW INLAND TONIGHT AND HIGHS WILL STRUGGLE TO REACH SINGLE DIGITS ABV ZERO ON FRIDAY. SAT...UPR RIDGING BUILDS FROM THE PLAINS INTO THE WRN GRTLKS AS SFC PRES GRADIENT RELAXES AHD OF RIDGE AXIS. LOOK FOR LES TO TAPER OFF FROM WEST ESPECIALLY LATE IN DAY. STILL EXPECT NUMEROUS SNOW SHOWERS NEAR LAKE SUPERIOR WITH SCT SHSN OR FLURRIES SOUTH. VOSS && MQT WATCHES/WARNINGS/ADVISORIES... WINTER STORM WARNING TODAY THROUGH FRIDAY NIGHT MIZ006-007. WINTER STORM WARNING TODAY MIZ085. WINTER WEATHER ADVISORY TODAY THROUGH FRIDAY MIZ001>003. WIND CHILL ADVY THIS AFTERNOON MIZ009. HEAVY FREEZING SPRAY WARNING IN EFFECT LAKE SUPERIOR. && $$ mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MIDLAND/ODESSA TX 223 PM CST THU JAN 29 2004 .SHORT TERM... ARCTIC COLD FRONT CONTINUES TO MAKE SLOW SOUTHWARD PROGRESS THROUGH THE TEXAS PANHANDLE THIS AFTERNOON AND WAS LOCATED ALONG A PLAINVIEW TO PADUCAH LINE AS OF 19Z. THE LATEST RUC AND ETA MODELS SEEM TO HAVE A DECENT HANDLE ON THE FRONTAL POSITION AND WE WILL GENERALLY FOLLOW THEIR SOLUTIONS IN BRINGING THE LEADING EDGE OF THE FRONT INTO THE FAR NORTHEASTERN CWA AROUND 00Z. THE COLD FRONT SHOULD PROGRESS SOUTH THROUGH THE NIGHT...THEN BECOME DIFFUSE TOMORROW OVER THE LOWER TRANS PECOS REGION. OTHERWISE...THE UPPER LOW SEEN ON WATER VAPOR IMAGERY OVER NORTHERN CHIHUAHUA WILL DRIFT OVER THE FAR SOUTHERN BIG BEND REGION. WV IMAGERY COMPARED WITH 400MB HGT PROGS SHOW THE MODELS ARE A LITTLE TOO FAR NORTH WITH THE CENTER OF CIRCULATION. THERE COULD BE A HIGH BASED SHOWER OR TWO OVER THE CHISOS AND DAVIS MOUNTAINS AREA TONIGHT...BUT WITH A VERY DRY SUB-CLOUD LAYER...LITTLE MORE THAN A FEW SPRINKLES IS EXPECTED. WE WILL LEAVE 10 POPS IN THE GRIDS BUT NOT MENTION IN THE ZONES. .LONG TERM... IN THE MID TERM...THERMAL RIDGE STARTS TO BUILD OVR SE NM FRI AS BRIEF UPPR LVL RIDGING BUILDS IN WAKE OF SHRTWV CURRENTLY OVR FAR W TX. HOWEVER...EXPECTED COLD FRONT THIS EVENING SHOULD MODERATE HIGHS A BIT...KEEPING THEM SIMILAR TO TDY/S. SATURDAY...LEE TROF DEVELOPS OVR THE FRONT RANGE AS NEXT TROF APPROACHES...BACKING FLOW TO THE SW FOR GOOD DOWNSLOPE WARMING TO WELL ABV NRML TEMPS. GRADIENT SHOULD TIGHTEN SUFFICIENTLY TO PRODUCE WINDY CONDITIONS IN THE GUADALUPES/DELAWARES SAT AFTERNOON/NIGHT. SUN...TROF ARRIVES...FORCING COLD FRONT THRU SUN MORNING FOR WINDY CONDITIONS MOST PLACES...AS WELL AS SLIGHTLY BLO NRML TEMPS SUN AFTERNOON. BOTH GFS AND ETA CAME IN A LITTLE WARMER THAN PREVIOUS RUN...BUT STILL ADVERTISING BEST UPGLIDE/LIFT JUST N AND NE OF THE AREA...SO WILL CONTINUE W/A DRY WEEKEND. MON/TUE LOOK DRY AS WELL...W/A SLIGHT WARMUP AS NW FLOW SLOWLY BACKS AS NEXT SYSTEM APPROACHES. IN THE LONG TERM...MODELS ARE IN RELATIVELY GOOD AGREEMENT BRINGING A BROAD SRN STREAM TROF THROUGH THE CWA WED OR WED NIGHT. GFS IS DEEPER AND FASTER...W/THE TROF OVR EXTREME W TX BY 12Z WED...WHILE THE EUROPEAN LAGS OVR SRN AZ. GFS BRINGS ASSOCIATED FRONT THRU WED NIGHT. DESPITE TIMING DIFFERENCES...THE TRACK OF THE TROF IN BOTH MODELS ARE SIMILAR ENUF TO WARRANT A MENTION OF WIND AND -SHRA WED OR WED NIGHT. WILL OPT FOR A COMPROMISE AND SHOTGUN WINDY CONDITIONS AND ISOLD SHOWERS WED. IT GOES W/OUT SAYING GRIDS WILL NEED TO BE FINE-TUNED BOTH AREALLY AND TEMPORALLY AS THIS EVENT NEARS AND FINER RES MODELS GET A BETTER HANDLE ON IT. GFS IMMEDIATELY DROPS ANOTHER SHRTWV INTO THE AREA THU...BUT WILL HOLD OF CONCERNS ABOUT THIS FOR NOW...AS THE TAIL END OF THE EUROPEAN SHOWS NO UPSTREAM INDICATIONS OF THIS. && .PRELIMINARY POINT TEMPS/POPS... BIG SPRING TX 30 56 37 66 / 0 0 0 0 CARLSBAD NM 29 62 37 66 / 0 0 0 0 DRYDEN TX 38 60 37 66 / 10 0 0 0 FORT STOCKTON TX 36 62 41 71 / 10 0 0 0 GUADALUPE PASS TX 34 57 39 58 / 0 0 0 0 HOBBS NM 27 61 35 65 / 0 0 0 0 MARFA TX 25 56 28 62 / 10 0 0 0 MIDLAND INTL AIRPORT TX 30 58 35 66 / 0 0 0 0 ODESSA TX 30 59 35 66 / 0 0 0 0 WINK TX 30 60 33 71 / 0 0 0 0 && .MAF WATCHES/WARNINGS/ADVISORIES... TX...NONE. NM...NONE. && $$ 06/44 tx SOUTH TEXAS FORECAST DISCUSSION NATIONAL WEATHER SERVICE CORPUS CHRISTI TX 1100 AM CST THU JAN 29 2004 .DISCUSSION...PRECIPITATION ONGOING OVER THE EASTERN THIRD OF FORECAST AREA AND OFFSHORE WATERS THIS MORNING. LATEST RUC AND ETA 12 SHOW GOOD ISENTROPIC OVER THE FORECAST AREA THIS MORNING WITH BEST FORCING SHIFTING NORTHEAST OF REGION THIS AFTERNOON SO EXPECT TO ADJUST POPS DOWN A LITTLE. MAX TEMPERATURES LOOK PRETTY GOOD FOR LATER TODAY...BUT MAY TWEAK DOWN ESPECIALLY OVER THE NE AND WEST. FOR MARINE...SCA TO CONTINUE OVER OFFSHORE WATERS DUE TO HIGH SEAS. && .PREVIOUS DISCUSSION...SHORT-TERM (TODAY THROUGH FRIDAY)... ISENTROPIC LIFT IN THE 295-300K LAYER REALLY GOING THIS MORNING WITH LIGHT RAIN AND LOW CEILINGS BEING REPORTED THROUGHOUT THE AREA. CRP VAD WINDS SHOWS 30KT LLJ AND GOOD WARM ADVECTION PATTERN IN PLACE AND AREA RADARS SHOW INCREASING PRECIP COVERAGE WITH A FEW STRONGER RETURNS OVER THE BRO COASTAL WATERS. WARM ADVECTION PATTERN REMAINS IN PLACE TODAY WITH UPPER LOW CURRENTLY OVER NORTH-CENTRAL MX CONTINUING TO MOVE SOUTHEAST. THIS FEATURE WILL APPROACH THE AREA LATER TONIGHT AND GUIDANCE IS CONSISTENT WITH DEVELOPING A LOW OVER THE COASTAL WATERS AND BRINGING A FRONT THROUGH OVERNIGHT. GFS IS A LITTLE FASTER WITH THE FRONT AND ALTHOUGH ETA BRINGS A WIND SHIFT THROUGH MOS TEMPS ON FRI ARE CONSIDERABLE WARMER THAN OTHER GUIDANCE. CURRENT THINKING IS TO LEAN TOWARD THE COOLER MAV NUMBERS GIVEN THE SHALLOW VERY COLD AIR CURRENTLY SITUATED OVER OK. DONT SEE ANY REASON WHY SOME OF THIS COOLER AIR SHOULDNT MAKE IT DOWN. MODELS HAVE UPPER LOW SITUATED JUST TO THE SOUTHWEST OF THE CWA ON FRI AND ARE HINTING AT SOME RESIDUAL MOISTURE HANGING AROUND. ALTHOUGH IT WILL BE VERY DIFFICULT TO LIFT ANYTHING ON FRI...ATMOSPHERE WILL BE UNSTABLE W/H5 TEMPS IN THE -20 TO -22 RANGE. COULD SEE A VERY ISOLATED STORM GO UP BUT ATTM THINK RISK IS TOO MINIMAL TO MENTION IN ZONES. MORNING SHIFT CAN PONDER THIS FURTHER. && .MARINE...SCA FOR OFFSHORE WATERS FOR TODAY. WINDS GUSTING TO 27KTS EARLY THIS MORNING W/7FT SEAS. GRADIENT WILL TIGHTEN SLIGHTLY TODAY AS UPPER LOW APPROACHES. && .LONG-TERM (FRIDAY NIGHT THROUGH WEDNESDAY NIGHT)...UPPER LOW STILL REMAINS TO THE WEST FRIDAY NIGHT. HAVE DECIDED TO MENTION LOW END POPS FOR THE GULF WATERS AS FAIRLY DEEP LAPSE RATES COULD PRODUCE AN ISOLATED THUNDERSTORM. WINDS ARE LIGHT SATURDAY MORNING AND AS TEMPS APPROACH DEWPOINTS COULD SEE SOME PATCHY FOG. LONG-RANGE MODELS IN DISAGREEMENT OVER THE NEXT FROPA. GFS IS NOW EVEN SLOWER AND UKMET/ECMWF/CANADIAN DON'T BRING THE FRONT IN TIL MONDAY. WILL NOT BITE ON THE SLOWER MODELS JUST YET...BUT HAVE DELAYED THE GFS SOLUTION BY ABOUT 6 HOURS. NO PRECIP EXPECTED WITH FRONT AS MOISTURE APPEARS TOO LIMITED. LONG-RANGE MODELS REALLY DIVERAGE AFTER THAT...WITH THE GFS/MRF BRINGING RETURN FLOW BY TUESDAY AND ECMWF/CANADIAN BRINGING ANOTHER RE-ENFORCING HIGH PRESSURE SYSTEM IN. MODELS DO CONCUR SOMEWHAT IN SWINGING AN UPPER LEVEL LOW ACROSS ON WEDNESDAY (IF ONE EXTRAPOLATES SOME OF THE MODELS). AS A RESULT AND TO FIT IN BETTER WITH SURROUNDING OFFICES...WILL MENTION A SLIGHT CHANCE OF PRECIP FOR WEDNESDAY. DUE TO THE UNCERTAINTIES IN THE MODEL SOLUTIONS...WILL HOLD OFF ON MAKING ANY SIGNIFICANT CHANGES TO THE TEMPERATURES AND WIND GRIDS AFTER MONDAY...ESPECIALLY SINCE IT IS FELT THAT THE MRF-MOS IS TOO WARM ON MAX TEMPS TUESDAY AND WEDNESDAY. && PRELIMINARY POINT TEMPS/POPS... CORPUS CHRISTI 67 54 64 48 69 / 70 30 10 10 00 VICTORIA 65 47 62 43 67 / 80 40 10 10 00 LAREDO 67 48 63 47 71 / 50 10 05 05 00 && .CRP...WATCHES/WARNINGS/ADVISORIES... SCA FOR GMZ270-275. && $$ 91/72 (SHORT-TERM) 86/GW (LONG-TERM) tx