AREA FORECAST DISCUSSION...UPDATE NATIONAL WEATHER SERVICE GOODLAND KS 846 PM MST SAT MAR 26 2005 .DISCUSSION...AN UPDATE IS ABOUT READY TO COME OUT. SKIES HAVE ALREADY CLEARED...AND HAVE ADJUSTED SKY COVER ACCORDINGLY. WINDS ARE LIGHT AND VARIABLE. RUC CATCHING THIS NICELY AND UPDATED WITH. ALSO MADE MINOR ADJUSTMENTS WITH THE DEWPOINTS. BASED ON CURRENT OBSERVATIONS AND LATEST GUIDANCE...TWEEKED OVERNIGHT MINS DOWN A TAD. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. NE...NONE. CO...NONE. && $$ BULLER ks AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LOUISVILLE KY 629 AM EST SAT MAR 26 2005 .SHORT RANGE (TODAY THRU MONDAY)... WELL...UPDATED THE FORECAST FOR THE THICKER FOG DEVELOPMENT ACROSS SRN KY. PHONE CALLS AND AREAS OBSERVATIONS DENOTE MUCH THICKER FOG. BOTH GLW AND TAYLORSVILLE HAVE 1/4 MILE AND BWG 3/4 MILE. WE HAVE SHORT TERM FORECASTS OUT FOR THE FOG. THERE HAS BEEN SOME STRATUS DEVELOPMENT WHICH IS IN WITH THE LATEST RUC H9 CONDENSATION PRESSURE DEFICIT WITH NELY SFC-H9 WINDS...AND SWLY FLOW OVER TN IS KEEPING BNA AT 100 BKN. STILL THINK THERE WILL BE AFTERNOON SUN IN THESE 2 SRN GROUPS. DAY SHIFTS BIG CHALLENGE TDA WILL BE THE LOW CLOUDS AND HOW THEY EVOLVE THROUGHOUT THE DAY. .LMK WATCHES/WARNINGS/ADVISORIES... .IN...NONE. .KY...NONE. && $$ JDG/CCS ky AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 330 PM EST SAT MAR 26 2005 .DISCUSSION... 12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A SPLIT FLOW ACRS NAMERICA. UPR GRT LKS IN DRY WNW FLOW ALF ON THE SRN PERIPHERY OF BROAD NRN BRANCH TROF CENTERED ARND POLAR VORTEX OVER NRN HUDSON BAY AND WELL TO THE N OF MORE ACTIVE SRN BRANCH FLOW ACRS THE SRN CONUS. AT THE SFC...W-E HI PRES RDG STRETCHES FM THE NRN PLAINS ACRS THE CNTRL GRT LKS...WITH WLY LLVL FLOW OVER THE FA. 12Z APX/GRB SDNGS DEPICT VERY DRY AIRMASS (PWAT AS LO AS 0.14 INCH AT APX) OVER THE UPR LKS...AND FA ENJOYING SUNNY DAY TDAY WITH TEMPS AWAY FM LK BREEZE INFLUENCE RISING WELL INTO THE 40S DESPITE DWPTS REMAINING MAINLY IN THE TEENS/LO 20S. AN AREA OF CLD NOTED OVER NRN MN AND ADJOINING ONTARIO ASSOCIATED WITH SUBTLE SHRTWV NR LK WINNIPEG AS OBSVD ON WV IMAGERY. LOOP OF STLT IMAGERY INDICATES THIS CLD MOVING MORE W-E AND ON TRACK TO STAY MAINLY N OF THE FA. ANOTHER SHRTWV PLOWING INTO THE PAC NW AND CAUSING HVY RA THERE. MAIN FCST CONCERNS THE NEXT FEW DAYS ARE TEMPS. FOR TNGT...SFC RDG RDG PROGGED TO SINK SLOWLY SWD AS LK WINNIPEG SHRTWV/ASSOCIATED CLD COVER BEST DEPICTED BY GFS H85-7 RH MOVE E TO THE N OF THE FA. ALTHOUGH SOME OF THIS CLD MAY BRUSH THE KEWEEANW... THE ONLY IMPACT OF THIS SYS MAY BE TO TIGHTEN THE PRES GRADIENT ACRS THE FA. THE SOMEWHAT STRONGER LLVL FLOW WL KEEP LO TEMPS HIER THAN THE CHILLY READINGS OBSVD THIS MRNG. LOOK FOR THE LOWER MINS BLO MOS GUIDANCE OVER THE INTERIOR SCNTRL CLOSER TO THE SFC RDG/WEAKER GRADIENT. ON SUN...SHRTWV NOW PLOWING INTO PAC NW FCST TO REACH NW ONTARIO BY 00Z MON. MODELS...ESPECIALLY GFS...SHOW AN INCRS IN MID/HI LVL RH ACRS MAINLY THE NRN TIER ZNS DURING THE AFTN. BUT EXPECT MOSUNNY SKIES ACRS THE S TOWARD CORE OF DRY AIR AND FARTHER FM SHRTWV TRACK/ DPVA/H85-5 QVECTOR CNVGC. FCST H85 TEMPS BY 00Z RANGE FM 0C ACRS THE N TO JUST ABOUT 2C ACRS THE WI BORDER ZNS. MIXING TO H85 AS HAS BEEN OBSVD WITHIN THIS AIRMASS ON NAM FCST SDNGS TMRW YIELDS TMAX WELL ABV MOS GUIDANCE FOR AREAS AWAY FM LK BREEZE COOLING THAT WL BE CONFINED MAINLY TO THE LK MI SHORE WITH EXPECTED H925 SW WIND. GFS/UKMET PERSIST ON GENERATING PCPN OVER THE NRN TIER ZNS ON SUN NGT AS SHRTWV TRACKS ACRS SRN ONTARIO. BUT PREFER DRIER NAM SOLN GIVEN DRY ANTECEDENT AIRMASS...LACK OF ANY SGFNT MSTR INFLOW...AND TRACK OF SHRTWV/LLVL FRONTOGENESIS TO THE N. GFS FCSTS AN UNREALISTICALLY HI PWAT OF 0.75 INCH WITH WNW FLOW ALF AND LACK OF ANY GLFMEX INFLOW. WL RESTRICT MENTION OF RA/SN TO THE NRN HALF OF LK SUP AS IN GOING FCST. INCRSG CLD COVER AND STEADY SW WIND IN SHARPER GRADIENT TO THE S OF SHRTWV TRACK WL HOLD LO TEMPS WELL ABV TNGTS READINGS. MON SHOULD BE A QUIET DAY DOMINATED BY SUBSIDENCE/ THINNING MID/HI CLD BEHIND DEPARTING SHRTWV INTO QUEBEC. H85 TEMPS FCST ARND 3C...AND FULL MIXING TO H85 ON ETA FCST SDNGS YIELDS TMAX AOA 60 OVER THE INTERIOR. BUT WEAK GRADIENT FLOW WL ALLOW FOR MESOHI DVLPMNT OVER THE COLDER GRT LKS AND LK BREEZE DVLPMNT/COOLING THAT WL NOT ALLOW THE HI TEMP TO RISE SO FAR. BUT WL TEND TO FAVOR THE HIER NGM MOS GUIDANCE FOR TMAX OVER THE INTERIOR FARTHER FM PSBL LK MODERATION. EXPECT A GENERAL INCRS IN MID/HI CLD MON NGT WITH MORE OF A SW FLOW DVLPG ALF IN ADVANCE OF SHRWTVS RIDING OUT OF THE W. GFS SHOWS H85 WARM FNT APRCHG LATE MON NGT TOWARD THE WRN ZNS...AND HAVE STUCK WITH A LO CHC POP FOR -RA THERE AFTER MIDNGT AND OVER THE ENTIRE FA ON TUE DESPITE HINTS THAT DRY LLVL AIR MAY TRY TO PERSIST. DIFFERENCES ABOUND ON THE DETAILS OF THE MID WEEK WEATHER... SPECIFICALLY ON THE INTERACTION BTWN THE NRN AND SRN BRANCH FLOWS. SO CONFIDENCE IN EXTENDED FCST IS QUITE LOW. THE 00Z/06Z GFS SHOW A FASTER NRN BRANCH SHRTWV PUSHING A COLD FNT THRU THE CWA BY EARLY WED...WITH A BUBBLE HI FILLING INTO THE UPR GRT LKS ON WED IN ADVANCE OF THE SRN BRANCH SHRTWV THAT TRACKS WELL TO THE S THRU THE OH VALLEY ON FRI WHILE HI PRES/MARITIME POLAR AIR DOMINATE THE UPR LKS. THE UKMET IS THE EXTREME ON THE OTHER END... SHOWING A PHASED DEEP SFC LO TRACKING FM THE CENTRAL PLAINS INTO THE CENTRAL LKS ON THU WITH HVY RA POSSIBLE OVER THE FA IN DEEP CYC FLOW. THE OPERATIONAL CNDN LOOKS MORE LIKE THE GFS...WHILE THE ECMWF IS A COMPROMISE BTWN THE TWO CAMPS. THE 12Z GFS HAS RETREATED FM THE BUBBLE HI SCENARIO AND NOW LOOKS MORE LIKE THE ECMWF. GIVEN THE SPREAD OF MODEL FCSTS...WILL FOLLOW THE ECMWF/GFS REFCST ENSEMBLE MEAN/CNDN ENSEMBLE MEAN FCSTS...WHICH HINT THAT RA WL OVERSPREAD THE FA N OF SFC WARM FNT ON TUE...THEN LINGER INTO AT LEAST EARLY THU. BUT WL FCST NO MORE THAN HI CHC POPS GIVEN GREAT UNCERTAINTY...WITH HIGHEST POP EARLY ON WED. SGNFT MODEL DIFFERENCES PERSIST INTO THE LATE WEEK. GENERALLY FOLLOWED NCEP MANUAL GUIDANCE FOR THIS TIME/ASSUMPTION THERE WL BE A ZONAL FLOW ALF. BUT GFS REFCST ENSEMBLE GUIDANCE INDICATES A COOLER PD MAY BE IN STORE...A TREND HINTED AT BY 12Z OPERATIONAL GUIDANCE AS WELL. COORDINATED WITH APX/GRB/DLH. && .MQT...WATCHES/WARNINGS/ADVISORIES...NONE. && $$ KC mi AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE BINGHAMTON NY 910 AM EST SAT MAR 26 2005 .SHORT TERM (TODAY - SUNDAY NIGHT)... UPDATE - SAT PIX SHOW CLEAR SKIES ACRS UPSTATE (OTHER THEN SOME LINGERING VLY FOG) BUT LOW CLDS OVER CNTRL PA ARE SLOWLY WORKING THEIR WAY N AND NE. 925/850 MB RH PROGS FROM THE MESOETA/RUC APPEAR TO HAVE A GOOD HNDL ON THIS, AND INDICATE THAT OVC CONDITIONS WILL MOVE INTO THE NRN TIER COUNTIES OF PA AND THE WYOMING VLY THIS AFTN. WILL CALL FOR INC CLDS OR BCMG CLDY THOSE AREAS. FURTHER TO THE N THE CRNT FCST OF MOSTLY SUNNY LOOKS FINE. ATTM FEEL THE CLD GRID/FCST FOR TNGT IS TOO OPTIMITIC AS PROFILES AND MDL DATA SHOW THIS LOW LVL MSTR WORKING N. GFS/ETA PROFILES SHOW SATURATED CONDITIONS BLO 850 MB, WITH TEMPS > -10C. THESE PROFILES SUGGEST THE PSBLTY OF -DZ OR -FZDZ. MENTION OF PCPN TNGT WAS REMOVED, BUT WILL CONSIDER ADDING IT BACK TO THE FCST WITH THE AFTN PCKG AFTER WE SEE THE 12Z RUNS. FOR NOW WILL JUST MODIFY CLD GRIDS TO SHOW MOSTLY CLDY CONDITIONS SPREADING NWD ACRS UPSTATE TNGT. PREV DISCUSSION... LOW PRESSURE WILL MOVE OUT OF TX NEXT 24H. THIS CYCLONE WILL HAVE AMPLE GULF MOISTURE FEEDING OUT AHEAD OF IT. AS UL TROF DIGS BEHIND SYSTEM...THE CYCLONE WILL STRENGTHEN AND FLOW WILL BECOME SOUTHWESTERLY OVER THE EASTERN CONUS. THE RESULT IN THE INTERIM WILL BE A SLOW WARMING TREND INTO NEW YORK AND PENNSYLVANIA...WHILE DEEP MOISTURE REMAINS OVER THE SOUTHERN PLAINS. STRONG MARCH SUN SHOULD PIERCE SCT CI W/O DIFFICULTY TODAY SO WILL FORECAST MOSTLY SUNNY CONDITIONS. HAVE EDGED A FEW DEGREES ABOVE MOS GUIDANCE AS WE SHOULD AT LEAST BE 2-4 DEGREES WARMER THAN FRIDAY GIVEN SLIGHT BL WARMING AND GREATER DEGREE OF SUNSHINE. WARM FRONT AHEAD OF PLAINS CYCLONE MAKES ITS WAY INTO SOUTHERN OHIO VALLEY OVERNIGHT. ATMOSPHERE BEGINS TO MOISTEN OVER NY/PA BUT THINK PARTLY CLOUDY WILL DESCRIBE MUCH OF FA. PLAINS TROF CLOSES INTO A LOW SUNDAY AND SFC CYCLONE SLOWLY DEEPENS. GFS DEPICTS NICE STREAM OF MOISTURE FLOWING OUT OF GULF WITH PLENTY OF OMEGA LIFT. CLOUDS WILL BE ON THE INCREASE AGAIN OVER CWA AND THINK THERE COULD BE SOME MIDDECK LIGHT PRECIPITATION OVER SOUTHERN HALF. WILL GO WITH CHC POP THROUGH SOUTHERN TIER OF NY. REMNANTS OF GULF MOISTURE AND FLOW OFF EASTERN SEABOARD WILL BRING RAIN INTO CWA OVERNIGHT SUNDAY. AT THIS POINT IT APPEARS THE BEST LIFT AND DEEPEST MOISTURE HOLD OFF UNTIL SUNRISE. HOWEVER LIKELY POPS SEEMS A SAFE BET SUNDAY NIGHT...WITH THE BULK OF THE EVENT AFTER SUNRISE MONDAY. WILL REISSUE ESF THIS SHIFT. DJP && .LONG TERM (SUNDAY NIGHT - FRIDAY)... IT STILL APPEARS THAT A FAIRLY SIGNIFICANT PRECIPITATION EVENT COULD BE IN THE OFFING FROM LATER SUNDAY NIGHT THROUGH MUCH OF MONDAY. ALTHOUGH FINER DETAILS DIFFER...MOST OF OUR LONGER RANGE GUIDANCE SUGGESTS THAT AN AMPLIFYING UPPER-LEVEL TROUGH WILL TEAM UP WITH A GOOD MOISTURE FEED DURING THIS PERIOD OVER THE EASTERN U.S. WE HAVE A LIKELIHOOD OF RAIN BOTH SUNDAY NIGHT AND MONDAY...THEN TAPERING BACK TO JUST A CHANCE BY MONDAY NIGHT. BOUNDARY LAYER TEMPERATURES MAY BE MARGINALLY COLD ENOUGH FOR SOME WET SNOW TO MIX IN...BOTH AT THE BEGINNING OF THIS EVENT SUNDAY NIGHT...THEN THE ENDING ON MONDAY NIGHT. FROM NEXT TUESDAY RIGHT THROUGH FRIDAY...WE KEPT CONSISTENT WITH THE PREVIOUS FORECAST PACKAGE. THE AFOREMENTIONED STORM SHOULD MOVE OUT BY TUESDAY...WITH DRY WEATHER LASTING INTO MID-WEEK. AN APPROACHING COLD FRONT COULD BRING SOME SHOWERS ON THURSDAY...THEN DRIER WEATHER RETURNS AGAIN BY THE END OF THE WEEK. OVERALL...TEMPERATURES SHOULD EXHIBIT AN UPWARD TREND CLOSER TO SEASONAL NORMALS NEXT WEEK. -MJ && .AVIATION(26/06Z - 27/06Z)... EXCEPT FOR EARLY MORNING PATCHY VALLEY FOG REDUCING VSBY/CIGS TO LIFR CONDITIONS (ELM), THE REST OF THE DAYLIGHT HOURS WILL BE VFR. ONLY CIRRUS WILL COVER THE SKY AT (UCA/SYR/ELM/BGM) WITH A MID DECK AT AVP. OVERNIGHT, LOW LEVEL MOISTURE WILL INCREASE WITH A OVC DECK AT 4K FT DEVELOPING FROM SOUTH TO NORTH. && .BGM WATCHES/WARNINGS/ADVISORIES... .NY...ESF ISSUED FOR POTL +RA SUNDAY NIGHT AND MONDAY. .PA...ESF ISSUED FOR POTL +RA SUNDAY NIGHT AND MONDAY. && $$ ny AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NEWPORT/MOREHEAD CITY NC 940 PM EST SAT MAR 26 2005 .SHORT TERM (REST OF TONIGHT)...NO UPDATE PLANNED. FCST ON TRACK AS WAA CLOUDINESS WILL SPREAD IN OVERNIGHT WITH 20-30 POPS FOR RAIN LATE. TEMPS OK. && .AVIATION...MIX OF VFR AND MVFR CIGS WILL GRADUALLY LOWER TO MAINLY MVFR OVERNIGHT WITH ISOLD IFR CIGS/VSBYS PSBL LATE. CONDITIONS WILL CONTINUE TO DETERIORATE SUN WITH RA DEVELOPING. && .MARINE...WEDGY TYPE SFC HIGH EXPECTED TO REMAIN IN PLACE OVERNIGHT ...RESULTING IN WINDS MORE NE THATN E. LATEST RUC AND ETA12 SUPPORT THIS TREND...AND WILL INITIALIZE WITH LATEST OBS AND USE BLEND OF ETA12 AND RUC FOR FCST OVERNIGHT. SEAS AT DUCK AND DIAMOND STILL RUNNING 4-5 FT AND WILL KEEP SCA FOR NRN WATERS WITH NE SWELL. && .MHX WATCHES/WARNINGS/ADVISORIES... NC...NONE. MARINE...SMALL CRAFT ADVISORY AMZ150-152-154. && $$ JBM nc AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE COLUMBIA SC 619 PM EST SAT MAR 26 2005 .SHORT TERM (REST OF TONIGHT)... UPDATED THE FORECAST AND MOVED BACK THE SHOWERS UNTIL LATE TONIGHT. INCREASING ISENTROPIC LIFT SHOULD RESULT IN SHOWERS DEVELOPING LATE TONIGHT. THE RUC SHOWS A BAND OF MID 20S CROSS TOTALS MOVING INTO THE AREA SO THUNDERSTORMS MAY OCCUR. EXPECT THE THUNDERSTORMS WILL BE MAINLY ELEVATED BECAUSE OF THE LOSS OF HEATING AND SURFACE-BASED INSTABILITY. && .PREVIOUS DISCUSSION... (ISSUED 241 PM EST SAT MAR 26 2005) SHORT TERM (TONIGHT THROUGH MONDAY)... UPPER LOW OVER NM THIS AFTERNOON FORECAST TO DEEPEN AS IT MOVES NORTHEAST THROUGH MONDAY. SEVERAL SHORT WAVES CROSS THE AREA TONIGHT THROUGH MONDAY. WARM FRONT SOUTH OF THE AREA WITH WEDGE HIGH PRESSURE BUILDING IN FROM THE NORTH. WARM FRONT STILL EXPECTED TO MOVE NORTH ACROSS THE AREA SUNDAY. FAVORED SLOWER MOVEMENT OF THE GFS IN TAKING FRONT INTO NORTH MIDLANDS THROUGH SUNDAY EVENING. SHORT WAVES ALONG WITH MODERATE INSTABILITIES AND GOOD SHEAR STILL FAVORABLE FOR SEVERE WEATHER SUNDAY THROUGH MONDAY MORNING. COLD FRONT WILL MOVE THROUGH MONDAY MORNING WITH UPPER TROUGH SWINGING THROUGH MONDAY AFTERNOON/EVENING. KEPT CATEGORICAL POPS FOR LATE TONIGHT INTO SUNDAY NIGHT. CHANCE OF SHOWERS LINGER MONDAY. LONG TERM (MONDAY NIGHT THROUGH SATURDAY)... DRY FORECAST TUESDAY THROUGH THURSDAY. HIGH PRESSURE TO BUILD ACROSS THE REGION BOTH SURFACE AND ALOFT TUESDAY AND WEDNESDAY. BY THURSDAY...HIGH PRESSURE SLIPS OFF THE COAST. MODELS HAVE SLOWED MOVEMENT OF NEXT FRONT. LOOKS TO CROSS THE REGION FRIDAY WITH UPPER TROUGH CROSSING SATURDAY. CHANCE OF PRECIP THURSDAY NIGHT INTO SATURDAY. TEMPS ABOVE NORMAL TUESDAY THROUGH THURSDAY THEN COOLING FRIDAY AND SATURDAY. AVIATION... MAIN FORECAST CONCERN THIS AFTERNOON IS SLOWLY IMPROVING SKY CONDITIONS ACROSS THE AREA. SATELLITE SHOWS WEDGE OF LOW CLOUDS/FOG SLOWLY THINNING ACROSS THE AREA. EXPECT CONDITIONS TO BECOME MVFR ACROSS THE CAE METRO AREA WITH VFR CONDITIONS POSSIBLE ACROSS THE CSRA REGION. SURFACE BOUNDARY ACROSS THE SOUTHERN PORTION OF THE AREA TODAY WILL SLOWLY MOVE NORTHWARD TONIGHT. ISENTROPIC LIFT INCREASES ACROSS THE AREA AND EXPECT SOME SHOWERS TO BEGIN TO DEVELOP AND MOVE NORTH/NORTHEAST ACROSS THE AREA TONIGHT. EXPECTING IFR/MVFR CONDITIONS OVERNIGHT. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$ 05 sc AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE ABERDEEN SD 940 AM CST SAT MAR 26 2005 .UPDATE...FIRST PERIOD UPDATE TO BUMP TEMPS UP A FEW DEGREES AGAIN TODAY...ESPECIALLY OUT WEST WHERE SNOWCOVER HAS PRETTY MUCH BECOME A NON-FACTOR UNDER ANOTHER DAY OF MAX SUNSHINE. UPPER AIR SOUNDINGS AND RUC PRIMARY PLAYERS IMPLICATED IN FORECAST UPDATE THIS MORNING FOR TEMPS. REMAINING FIELDS ROBUST AS ONE COULD ASK FOR. DORN .PREVIOUS DISCUSSION... SHORT TERM...TODAY THROUGH MONDAY NIGHT AGAIN THE MAIN CONCERNS THROUGH THE SHORT RANGE WILL BE TEMPS...AND THEN CHC OF PRECIP LATE IN THE FORECAST. GUIDANCE UNDERESTIMATED TEMPS ON FRIDAY OVER AREAS THAT GOT PLENTY OF SUNSHINE. SUSPECT GUIDANCE COULD BE A LITTLE LOW TODAY HOWEVER A SUN FILTERING AREA OF CLOUDS SHOULD MOVE ACROSS THE CWA THUS DIDNT GO TOO MUCH OVER THE PREVIOUS FOREAST. SUNDAY AND MONDAY STILL APPEAR TO BE THE WARMEST DAYS. STEEPER LOW LEVEL LAPSE RATES AND WARMING SPREADING OFF THE HIGH PLAINS SHOULD SUCCEED IN BRINGING MILD TEMPERATURES TO THE FORECAST AREA. NOTCHED UP MAX T GRIDS A BIT BOTH DAYS. FOR MONDAY NIGHT SEE NEXT SYSTEM EXITING THE ROCKIES AND MOVING EAST IN THE CONTINUED PROGRESSIVE MID LEVEL PATTERN. MODELS INDICATE SOME MOISTURE POOLING NEAR APPROACHING FRONTAL BOUNDARY...THAT ALONG WITH ATTENDENT STEEP LOW LEVEL LAPSE RATES AND WEAK INSTABILITY SUGGEST A CHANCE OF SHOWERS BEHIND THE FRONTAL BOUNDARY. THUNDER IS POSSIBLE BUT EXPECTED TO BE ISOLATED THUS WILL LEAVE OUT OF GRIDS FOR NOW AND JUST GO WITH THE SPRING SHOWERS. .LONG TERM...TUESDAY THROUGH FRIDAY LOOKING AT SOME PRETTY SIGNIFICANT DIFFERENCES IN THE MODELS THIS RUN...ESPECIALLY IN THE SURFACE PATTERN. THE GFS TRIES TO DEVELOP A FAIRLY SIGNIFICANT LOW OVER THE CENTRAL PLAINS AROUND MID WEEK THAT THE OTHER MODELS KEEP WEAKER AND FURTHER TO THE SOUTHEAST. WITH THE GFS BEING THE OUTLIER...HAVE OPTED TO STICK CLOSER TO AN ECMWF/NOGAPS/DGEX SOLUTION. AN UPPER RIDGE WILL BE OVER THE OHIO VALLEY ON TUESDAY WITH A BROAD TROUGH OVER THE CENTRAL AND WESTERN PART OF THE COUNTRY. THIS TROUGH REACHES THE PLAINS ON WEDNESDAY...THEN PUSHES EAST OF THE REGION ON THURSDAY...ALLOWING FOR A BUILDING RIDGE TO PUSH OVER THE CENTRAL PART OF THE COUNTRY ON FRIDAY. SURFACE LOW PRESSURE WILL BE OVER THE WESTERN AND CENTRAL DAKOTAS EARLY TUESDAY...THEN SLIDES QUICKLY TO THE EAST DURING THE DAY. THIS SYSTEM LOOKS TO BE MOVING MUCH FASTER THAN PREVIOUS MODEL RUNS INDICATED...WHICH MAKES FOR LESS OF A CHANCE FOR PRECIPITATION OVER THE ABR CWA. THEREFORE...HAVE REMOVED MENTION OF PRECIPITATION FOR TUESDAY AFTERNOON AND TUESDAY NIGHT...WITH BETTER CHANCES LIKELY TO BE SOUTH AND EAST OF THE CWA. HIGH PRESSURE PUSHES OUT OF THE ROCKY MOUNTAIN REGION AND OVER THE PLAINS ON WEDNESDAY...THEN REMAINS THE DOMINANT FEATURE THROUGH FRIDAY. HAVE LOWERED TEMPS JUST A BIT TO START THE PERIOD...WITH THE THERMAL RIDGE PUSHING EAST OF THE CWA FAIRLY QUICKLY ON TUESDAY. STILL SHOULD SEE TEMPS SLIGHTLY ABOVE NORMAL THOUGH AS H85 TEMPS REMAIN ABOVE ZERO. TEMPS DURING THE LATTER HALF OF THE PERIOD LOOK TO BE JUST A BIT COOLER UNDER THE INFLUENCE OF THE SURFACE HIGH. H85 TEMPS DROP BACK TO AROUND OR JUST BELOW ZERO BOTH THURSDAY AND FRIDAY. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. && $$ TDK/AP sd AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE LUBBOCK TX 1018 PM CST SAT MAR 26 2005 .UPDATE... PRECIPITATION SLOWLY WINDING DOWN FROM NORTH TO SOUTH THIS EVENING. LATEST WV/IR SATELLITE IMAGERY INDICATED UPPER LOW OVER THE SOUTHEAST LOW ROLLING PLAINS NEAR OR JUST EAST OF ASPERMONT. AS A RESULT CWFA NOW UNDER THE WRAP AROUND MOISTURE. LIGHT SNOW CONTINUES FROM NEAR TULIA AND SILVERTON SOUTH TO LUBBOCK AND CROSBYTON. FURTHER EAST AND SOUTH THE PRECIPIATION WAS ALL RAIN FROM DICKENS TO GUTHRIE AND POST TO ASPERMONT. HIGHEST SNOW REPORT THIS EVENING WAS 7 INCHES AT VIGO PARK AND 3 TO 4 INCHES OVER NORTHWEST PARMER COUNTY. CURRENTLY EXPECT MOST OF THE PRECIPITATION TO COME TO AN END SHORTLY AFTER MIDNIGHT...BUT HAVE RETAINED A CHANCE OF POPS SOUTHEAST CWFA AS SYSTEM SLOWLY PULLS AWAY FROM THE AREA. HAVE ALSO CANCELLED THE WINTER WEATHER ADVISORY ISSUED EARLIER THIS AFTERNOON. LATEST RUC INDICATED SATURATION AFTER MIDNIGHT...THUS HAVE INSERTED PATCHY FOG ON THE CAPROCK AS WINDS RELAX WITH DEPARTURE OF UPPER SYSTEM. && .LUB WATCHES/WARNINGS/ADVISORIES... TX...NONE. && $$ 05/11 tx AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CORPUS CHRISTI TX 830 PM CST SAT MAR 26 2005 .UPDATE...SFC BOUNDARY BASED ON OBS AND RADAR AT 02Z LOCATED FM SOUTH OF HEBBRONVILLE TO CORPUS CHRISTI THEN EAST INTO THE MIDDLE TEXAS COASTAL WATERS. FRONT WILL CONTINUE SOUTH THRU THE EVENING...PUSHED ALONG BY STG 3 HR PRESS RISES NOTED TO THE WEST AND NORTHWEST. RUC ANALYSIS SHOWS STG 85 KT H5 JET CORE IN BASE OF TROF NOW MOVING INTO EWX SW ZONES AND CRP EXTREME NW ZONES. H25 JET CORE ACROSS S-CTRL TX...POSITIONING FAVORED RRQ ACROSS NRN ZONES. VORT ADVECTION (H7-H3 Q-V CONV) ALSO INCREASING ACROSS THE NW ZONES OVR THE PAST 2 HOURS. IN RESPONSE...ELEVATED CONVECTION HAS DEVELOPED FM LIVE OAK COUNTY SW INTO NE WEBB/NRN DUVAL COUNTIES. EXPECT DEVELOPMENT OF CONVECTION AND MOVEMENT EAST THRU REMAINDER OF EVENING AS DYNAMICS SPREAD ENE. COOLING MID LEVEL TEMPS/STEEPENING LAPSE RATES COULD SUPPORT SOME ELEVATED THUNDER. WILL NUDGE POPS JUST A TAD (NOT TOO MUCH)...TAPERING OFF AFTER MIDNIGHT. WON'T COMPLETELY REMOVE AFTER MIDNIGHT AS MODELS INDICATING MAIN H5 VORT LOBE MOVES ACROSS. (HOWEVER JET DYNAMICS AND Q-V CONV APPEARS TO HAVE SHIFTED NE BY THEN. WINDS WILL INCREASE THRU THE EVENING (STG PRESS RISES NOTED NW WITH HDO/UVA GUSTING OVR 30 KTS) BECOMING WINDY IN MANY LOCATIONS. && .MARINE...STRONG OFFSHORE FLOW WILL DEVELOP THIS EVENING AN OVERNIGHT BEHIND STRONG LATE SEASON COLD FRONT OVERNIGHT. WINDS WILL LIKELY REACH 25 KNOTS SUSTAINED WITH GUSTS NEAR GALE FORCE OVER THE GULF WATERS. WINDS WILL REMAIN STRONG THROUGH EARLY SUN AFTN THEN WEAKEN AS HIGH PRESSURE SETTLE INTO THE REGION. ISOL/SCT SHOWERS/TSTMS ALSO EXPECTED ACROSS MAINLY THE WATERS NW OF PORT ARANSAS OVERNIGHT IN RESPONSE TO UPR LVL DISTURBANCE. && .AVIATION...EXPECT MVFR CONDITIONS (LOW CEILINGS) TO DEVELOP AREAWIDE OVERNIGHT. SEA FOG ALG THE COAST SOUTH OF RKP WL STEADILY DISSIPATE AS DRIER AIR FILTERS INTO THE REGION TNGT BEHIND THE FRONT. SFC WIND GUSTS AROUND 25KT ANTICIPATED OVERNIGHT GENERALLY EAST OF US ROUTE 77. ISOL/SCT SHOWERS/THUNDERSTORMS...ALG WITH ASSOCIATED IFR CEILINGS...ARE ANTICIPATED OVER THE REGION OVERNIGHT UNTIL AROUND 12Z SUN. VFR CONDITIONS WL DEVELOP FROM N TO S ACRS THE REGION BEGINNING AROUND 14Z SUN. && .CRP WATCHES/WARNINGS/ADVISORIES...SMALL CRAFT ADVISORY ALL MARINE ZONES. && $$ 76...SHORT-TERM 87...LONG-TERM tx AREA FORECAST DISCUSSION...CORRECTED NATIONAL WEATHER SERVICE LAKE CHARLES LA 345 AM CST SUN MAR 27 2005 .DISCUSSION...STRONG TO SEVERE THUNDERSTORMS MOVING ACROSS THE HOUSTON AREA THIS MORNING HAVE PROMPTED THE ISSUANCE OF A SEVERE THUNDERSTORM WATCH UNTIL 8 AM FOR THE ENTIRE AREA. THESE STORMS HAVE HAD A HISTORY OF PRODUCING GOLF BALL SIZE HAIL...HOWEVER THEY SEEM TO BE WEAKENING AS THEY APPROACH THE WESTERN PORTIONS OF THE CWA. RUC INDICATES AN UPPER LEVEL JET MAX OF 126 KT ROTATING AROUND THE BASE OF THE UPPER LOW INTO SE TX...WHICH APPEARS TO BE AIDING IN DEVELOPMENT OF THESE STORMS. THE UPPER LOW IS CURRENTLY LOCATED OVER N CENTRAL TX AND WILL BE MOVING EAST TODAY. AT THE SURFACE...LOW PRESSURE IS LOCATED NE OF JAN WITH THE COLD FRONT EXTENDING SOUTHWEST ACROSS SE LA AND INTO THE NORTHERN GULF. BESIDES DEALING WITH THIS MORNING'S SEVERE WEATHER...THE MAIN FORECAST ISSUE FOR TODAY IS CLOUDS AND TEMPS. ETA AND GFS INDICATE MOISTURE LINGERING THROUGH 06Z MONDAY...ESPECIALLY ACROSS THE NORTHERN ZONES. AFTERNOON TEMPS WILL DEPEND ON HOW LONG THE CLOUDS HANG AROUND. CURRENTLY PLAN TO GO A BIT BELOW MAV GUIDANCE SINCE EXPECT CLOUDS THROUGH MOST OF THE AFTERNOON. OVERNIGHT LOWS WILL BE BELOW NORMAL MONDAY AND TUESDAY MORNING WITH CLEAR SKIES AND WEAK WINDS ALLOWING RADIATIONAL COOLING TO MAXIMIZE. WILL BEGIN TO SEE RETURN FLOW FROM THE GULF ON TUESDAY WITH MOISTURE RETURNING TO THE AREA ON WEDNESDAY. NEXT CHANCE OF SHOWERS AND THUNDERSTORMS WILL BE THURSDAY AND FRIDAY AS THE NEXT FRONT MAKES ITS WAY ACROSS THE AREA. LOOKS LIKE BEST UPPER LEVEL SUPPORT WITH THIS SYSTEM WILL BE NORTH OF THE AREA...BUT WILL MONITOR DURING THE WEEK. DRY WEATHER WILL RETURN FOR NEXT WEEKEND. && .AVIATION...MVFR TO IFR CONDITIONS ACROSS THE AREA THIS MORNING MAINLY DUE TO LOW CEILINGS ACROSS THE AREA. LOWEST CIGS AROUND 1000 FT OVER S CENTRAL LA. SHOWERS AND THUNDERSTORMS WILL MOVE ACROSS THE AREA DURING THE MORNING HOURS. CONDITIONS SHOULD BE IMPROVING THIS AFTERNOON...BECOMING CLEAR BY TONIGHT. && .MARINE...STRONG NORTHERLY WINDS WILL CONTINUE OVER THE COASTAL WATERS. WINDS WILL BE AROUND 20 TO 25 KNOTS...WITH SEAS AROUND 5 TO 7 FEET. WINDS WILL SUBSIDE MONDAY...BECOMING SOUTHERLY BY TUESDAY AS HIGH PRESSURE MOVES EAST. && .PRELIMINARY POINT TEMPS/POPS... KLCH 62 45 72 49 / 30 0 0 0 KBPT 60 44 72 49 / 30 0 0 0 KAEX 58 43 71 48 / 50 0 0 0 KLFT 62 44 72 48 / 30 0 0 0 && .LCH WATCHES/WARNINGS/ADVISORIES... LA...SVR TSTM WATCH 95 LAZ027>033-041-042-051-043>045-052>055 TX...SVR TSTM WATCH 95 TXZ180>182-201-215-216. SCA GMZ450-455-470-475. && $$ la AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SHREVEPORT LA 245 AM CST SUN MAR 27 2005 .DISCUSSION... ALTHOUGH MUCH OF THE AREA FAILED TO RECORD RAIN DESPITE THE POTENTIAL FOR STRONG THUNDERSTORM DEVELOPMENT...AT LEAST AN EXPANDING AREA OF WIDESPREAD SHOWERS LOOKS EMMINENT TO ENGULF MUCH OF THE AREA LATE TONIGHT ACROSS EAST TEXAS...AND SPREAD INTO LA...AND TO SOME EXTENT...OK/AR PORTIONS OF AREA DURING THE MORNING. MOST THUNDERSTORMS CONFINED TO NEAR COASTLINE FOR NOW...BUT PUT IN EMBEDDED THUNDER SOUTHERN PORTIONS THIS MORNING...AS RUC INDICATES SIGNIFICANT SPEED DIVERGENCE IN UPPER FLOW SOUTH OF INTERSTATE 20. SHOULD SEE ALL PRECIP CLEAR THE AREA BY LATE THIS AFTERNOON...WITH OVERCAST DECK JUST STARTING TO ERODE OVER WESTERN SECTIONS BY THEN. WITH GUSTY NW WINDS CONTINUING MOST OF THE DAY...CLOUDS AND WIND WITH TEMPS RISING LITTLE FROM OVERNIGHT LOWS...RATHER GLOOMY FOR AN EASTER SUNDAY BUT AT LEAST MINIMAL THREATENING WEATHER IN ARKLATEX. SMALL HAIL COULD BE NOTED IN STRONGER CELLS DUE TO STRONG UPPER DIVERGENCE AND COOL TEMPS. HOWEVER...INSTABILITY WILL BE EASILY ELEVATED. SOUTHERLY FLOW WILL GET GOING MONDAY NIGHT...ALTHOUGH BOUNDARY LAYER MOISTURE RETURN LOOKING MINIMAL AT FIRST. THUS...WILL TAKE A FULL COUPLE OF DAYS OF SOUTHERLY FLOW TO EVEN PRODUCE MARGINAL MOISTURE FOR CONVECTION AS UPPER LOW PASSES JUST NORTH OF AREA. PUT IN CHANCE NORTH...NEAR LOW AND ONLY SLIGHT CHANCE ELSEWHERE...FOR WED NIGHT AND THURSDAY. AIR THEN LOOKING VERY DRY FOR WEEKEND... WHICH SHOULD BE WELCOME...AS LONG AS AREA GETS SOME NEEDED RAIN BEFORE THEN. && .PRELIMINARY POINT TEMPS/POPS... SHV 54 41 71 50 / 70 0 0 0 MLU 56 41 69 47 / 70 0 0 0 DEQ 48 36 71 48 / 50 0 0 0 TXK 52 39 70 50 / 70 0 0 0 ELD 52 39 69 47 / 70 0 0 0 TYR 50 39 73 53 / 70 0 0 0 GGG 53 39 72 52 / 70 0 0 0 LFK 56 39 72 53 / 90 0 0 0 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...NONE. LA...NONE. OK...NONE. TX...NONE. && $$ VII la AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE ALBUQUERQUE NM 935 PM MST SAT MAR 26 2005 .UPDATE... REMOVED POPS OVER ALL LOCATIONS TONIGHT WITH THE EXCEPTION OF A PERSISTING BAND OF LIGHT QPF WITHIN AN AREA OF WEAK ASCENT... STRETCHING FROM CUBA TO SOCORRO. KEPT ISOLATED WORDING PRIOR TO MIDNIGHT FOR THESE AFOREMENTIONED LOCATIONS. WILL THE FOG FORM TONIGHT IS THE NEXT QUESTION. LATEST MODEL GUIDANCE SUGGESTING NOTHING WILL DEVELOP. NAM BUFKIT LACKING IN THE FOG DEPARTMENT AS WELL. WEB RUC GRAPHICS PAINTING SOME LIGHT FOG IN THE WEST CENTRAL AND NRN MOUNTAINS AS WELL AS THE CANADIAN RIVER VALLEY. STILL A BIT LEERY...ESPECIALLY WITH PCPN EARLIER IN THE DAY AND EXCELLENT RADIATIONAL COOLING EXPECTED. THEREFORE...WILL LEAVE INHERITED PATCHY FOG LANGUAGE IN ZONES TO BE SAFE. UPDATED PRODUCTS WILL BE OUT SHORTLY. DPORTER && .PREV DISCUSSION 300 PM MST SAT MAR 26 2005...WILL ALLOW SNOW ADVISORIES TO EXPIRE AT 5 PM TODAY...HOWEVER SCATTERED SNOW SHOWERS WILL CONTINUE INTO THE EVENING ON THE FAR EASTERN PLAINS. AS THE UPPER LOW MOVES EAST INTO TEXAS THIS EVENING...ISOLATED RAIN AND SNOW SHOWERS WILL GRADUALLY DIMINISH MAINLY ALONG AND EAST OF A LINE FROM CHAMA TO SOCORRO. A FEW THUNDERSTORMS WILL ALSO LINGER IN THE SE THIS EVENING. CLOUDS WILL GRADUALLY CLEAR TONIGHT...EXPOSING THE FRESH SNOW TO RAPID RADIATIONAL COOLING. PATCHY FOG AND LOW CLOUDS WILL RESULT JUST ABOUT ANYWHERE FRESH SNOW EXISTS ON THE GROUND... INCLUDING THE WC MOUNTAINS...N MOUNTAINS...UPPER RIO GRANDE VALLEY...AND THE EAST CENTRAL AND NORTHEAST PLAINS. A RIDGE WILL BUILD OVER THE AREA ALOFT AND KEEP THE WEATHER DRY UNTIL MONDAY NIGHT...WHEN AN UPPER TROUGH WILL APPROACH FROM THE WEST AND SUBJECT THE NW QUARTER TO A SLIGHT CHANCE OF RAIN AND SNOW SHOWERS. THE TROUGH WILL PASS TO THE EAST TUESDAY NIGHT WITH RAIN AND SNOW SHOWERS THAT WILL FAVOR MAINLY THE NORTH AND WEST. ANOTHER TROUGH WILL FOLLOW RAPIDLY ON ITS HEALS WITH A POTENTIALLY STRONG MID WEEK BACK DOOR COLD FRONT THAT WILL KEEP THE WEATHER COOL AND UNSETTLED INTO THE LATTER PART OF THE WEEK. && .ABQ WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 44/46 nm AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CORPUS CHRISTI TX 1100 PM CST SAT MAR 26 2005 .UPDATE...UPDATED ZONES AND GRIDS TO BUMP UP WINDS SPEEDS AND GUSTS. MSAS ANALYSIS REVEALS VERY STRONG 3 HR PRESS RISES (6 MB) HAVE OCCURED ACROSS THE RIO GRANDE PLAINS. PREVIOUS UPDATE BELOW... && .PREVIOUS UPDATE...SFC BOUNDARY BASED ON OBS AND RADAR AT 02Z LOCATED FM SOUTH OF HEBBRONVILLE TO CORPUS CHRISTI THEN EAST INTO THE MIDDLE TEXAS COASTAL WATERS. FRONT WILL CONTINUE SOUTH THRU THE EVENING...PUSHED ALONG BY STG 3 HR PRESS RISES NOTED TO THE WEST AND NORTHWEST. RUC ANALYSIS SHOWS STG 85 KT H5 JET CORE IN BASE OF TROF NOW MOVING INTO EWX SW ZONES AND CRP EXTREME NW ZONES. H25 JET CORE ACROSS S-CTRL TX...POSITIONING FAVORED RRQ ACROSS NRN ZONES. VORT ADVECTION (H7-H3 Q-V CONV) ALSO INCREASING ACROSS THE NW ZONES OVR THE PAST 2 HOURS. IN RESPONSE...ELEVATED CONVECTION HAS DEVELOPED FM LIVE OAK COUNTY SW INTO NE WEBB/NRN DUVAL COUNTIES. EXPECT DEVELOPMENT OF CONVECTION AND MOVEMENT EAST THRU REMAINDER OF EVENING AS DYNAMICS SPREAD ENE. COOLING MID LEVEL TEMPS/STEEPENING LAPSE RATES COULD SUPPORT SOME ELEVATED THUNDER. WILL NUDGE POPS JUST A TAD (NOT TOO MUCH)...TAPERING OFF AFTER MIDNIGHT. WON'T COMPLETELY REMOVE AFTER MIDNIGHT AS MODELS INDICATING MAIN H5 VORT LOBE MOVES ACROSS. (HOWEVER JET DYNAMICS AND Q-V CONV APPEARS TO HAVE SHIFTED NE BY THEN. WINDS WILL INCREASE THRU THE EVENING (STG PRESS RISES NOTED NW WITH HDO/UVA GUSTING OVR 30 KTS) BECOMING WINDY IN MANY LOCATIONS. && .MARINE...STRONG OFFSHORE FLOW WILL DEVELOP THIS EVENING AN OVERNIGHT BEHIND STRONG LATE SEASON COLD FRONT OVERNIGHT. WINDS WILL LIKELY REACH 25 KNOTS SUSTAINED WITH GUSTS OVER GALE FORCE OVER THE GULF WATERS. WINDS WILL REMAIN STRONG THROUGH EARLY SUN AFTN THEN WEAKEN AS HIGH PRESSURE SETTLE INTO THE REGION. ISOL/SCT SHOWERS/TSTMS ALSO EXPECTED ACROSS MAINLY THE WATERS NW OF PORT ARANSAS OVERNIGHT IN RESPONSE TO UPR LVL DISTURBANCE. && .AVIATION...EXPECT MVFR CONDITIONS (LOW CEILINGS) TO DEVELOP AREAWIDE OVERNIGHT. SEA FOG ALG THE COAST SOUTH OF RKP WL STEADILY DISSIPATE AS DRIER AIR FILTERS INTO THE REGION TNGT BEHIND THE FRONT. SFC WIND GUSTS AROUND 25KT ANTICIPATED OVERNIGHT GENERALLY EAST OF US ROUTE 77. ISOL/SCT SHOWERS/THUNDERSTORMS...ALG WITH ASSOCIATED IFR CEILINGS...ARE ANTICIPATED OVER THE REGION OVERNIGHT UNTIL AROUND 12Z SUN. VFR CONDITIONS WL DEVELOP FROM N TO S ACRS THE REGION BEGINNING AROUND 14Z SUN. && .CRP WATCHES/WARNINGS/ADVISORIES...SMALL CRAFT ADVISORY ALL MARINE ZONES. && $$ 76...SHORT-TERM 87...LONG-TERM tx AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE PUEBLO CO 413 AM MST SUN MAR 27 2005 .SHORT TERM... (TODAY AND TONIGHT) MAIN SHORT TERM CONCERNS REMAIN TEMPERATURES AND INCREASING WINDS ALOFT TONIGHT. CURRENT WATER VAPOR IMAGERY AND RUC UPPER AIR ANALYSIS INDICATING MODERATE NORTHWEST FLOW ALOFT ACROSS THE REGION...AS UPPER TROUGH ACROSS CENTRAL HIGH PLAINS CONTINUES TO MOVE EAST AND UPPER LEVEL RIDGING CONTINUES TO BUILD ACROSS THE DESERT SW AND GREAT BASIN. TODAY...FLAT UPPER LEVEL RIDGING BUILDS ACROSS THE STATE WITH FLOW ALOFT BECOMING MORE WESTERLY ALLOWING FOR WEAK LEE TROUGHING TO DEVELOP ACROSS THE PLAINS. WARMING ALOFT AS RIDGE BUILDS WITH H7 TEMPS PROGGED BETWEEN -2C AND +2C...ALONG WITH WEAK DOWNSLOPE FLOW AND MOSTLY CLEAR SKIES...WILL ALLOW FOR HEALTHY WARM UP FROM YESTERDAY...AND HAVE GENERALLY FOLLOWED WARMER SIDE OF GUIDANCE TODAY...SAVE AREAS SOUTH AND WEST OF THE ARKANSAS RIVER AND CENTRAL PORTIONS OF THE SAN LUIS VALLEY...WHERE LATE AFTERNOON VISIBLE SAT PICS INDICATED SNOW COVER. TONIGHT...WEST TO SOUTHWEST FLOW ALOFT INCREASES AS NEXT PAC NW SYSTEM MOVES INTO THE GREAT BASIN. LEE TROUGHING STRENGTHENS OVERNIGHT ALONG WITH H7 TEMPS WARMING TO BETWEEN +3C AND +6C...WILL MAKE OVERNIGHT LOWS TRICKY. HAVE WARMED LOWS A TAD ACROSS THE HIGHER TERRAIN AND LOWER EASTERN SLOPES WITH WESTERLY GAP FLOWS DEVELOPING. HAVE GONE ON THE COOL SIDE OF GUIDANCE ACROSS THE NORMAL COOL SPOTS ACROSS THE LOWER ARKANSAS VALLEY...THINKING WINDS TO STAY DECOUPLED LONG ENOUGH FOR TEMPS TO TANK EARLY. MODEL X-SECTIONS INDICATING MT TOP STABLE LAYER DEVELOPING OVERNIGHT WITH POSSIBLE WEAK MT WAVE AS WESTERLY FLOW INCREASES...HOWEVER STRONGEST WINDS LOOK TO STAY ACROSS THE HIGHEST TERRAIN ATTM. -MW .LONG TERM... (MONDAY THROUGH SATURDAY) ...BREEZY AND WARM MONDAY AND TUESDAY...POSSIBLY COOL...WINDY AND WET TUESDAY NIGHT AND WEDNESDAY...THEN BACK TO BREEZY AND WARM AGAIN... MONDAY AND TUESDAY GENERALLY LOOK BREEZY AND WARM...UNDER DOWNSLOPE FLOW CONDITIONS. FLOW ALOFT IS SOUTHWESTERLY...WITH A LEE THROUGH ON THE PLAINS. THE COMBINATION OF A WARM AIRMASS AND COMPRESSIONAL DOWNSLOPE HEATING SHOULD SEND AFTERNOON TEMPERATURES SOARING TO THEIR HIGHEST LEVELS THUS FAR THIS SEASON THESE DAYS. POSSIBLE HITCH IN THE FORECAST IS A WEAK DISTURBANCE TO RIPPLE ACROSS THE STATE ON MONDAY NIGHT AND TUESDAY...WHICH COULD SEND A POCKET OF INSTABILITY ACROSS THE MOUNTAINS...AND A WEAK FRONT SOUTH ACROSS THE PLAINS. HAVE SOME LOW TO MEDIUM POPS IN THE FORECAST TO REFLECT THIS. WINDS MONDAY AND TUESDAY WILL BE BREEZY TO WINDY AT TIMES...WITH SOUTHWESTERLY WIND GUSTS UP TO 35 MPH POSSIBLE ON THE PLAINS...AND UP TO 45 MPH IN THE MOUNTAINS. THEN...TUESDAY NIGHT AND WEDNESDAY...A MORE SIGNIFICANT DISTURBANCE TO MOVE INTO COLORADO. THERE HAS BEEN A PRETTY MAJOR DISCREPANCY BETWEEN THE ETA AND GFS ON THE STRENGTH OF THIS SYSTEM AS IT MOVES ACROSS...WITH THE GFS BEING MUCH STRONGER AND DEEPER...AND THE ETA MUCH WEAKER AND MORE PROGRESSIVE. THE GFS WAS TENDING TO CLOSE THE LOW...WHILE THE ETA WAS FAVORING AN OPEN SOLUTION. WELL...THE 06Z RUN OF THE ETA IS NOW MUCH STRONGER AND DEEPER WITH ITS SOLUTION FOR TUESDAY NIGHT AND WEDNESDAY...WHILE THE 06Z GFS IS NOW MUCH WEAKER AND MORE PROGRESSIVE. SO WHAT'S GOING TO HAPPEN? DUNNO. FOR NOW... WILL KEEP LOW TO MID GRADE POPS IN THE FORECAST...WHICH SEEMS A REASONABLE PATH UNTIL FORECAST BECOMES MORE CERTAIN. IF THE SLOWER... DEEPER...MORE CLOSED SOLUTION OCCURS...FORECAST FOR THE TUESDAY NIGHT AND WEDNESDAY TIME FRAME WILL NEED A MAJOR OVERHAUL...TO INDICATE MUCH BETTER ODDS FOR RAIN AND SNOW. IT'LL CONTINUE TO BE WINDY AT TIMES TUESDAY NIGHT INTO WEDNESDAY...ESPECIALLY ACROSS THE PLAINS ON WEDNESDAY AS A POTENTIALLY POTENT COLD FRONT MOVES THROUGH. COULD SEE SOME NORTHERLY WIND GUSTS TO AROUND 50 MPH ON THE PLAINS THIS DAY AS IT LOOKS RIGHT NOW. BY THURSDAY...SYSTEM...HOWEVER STRONG...IS OUT OF HERE. THE PATTERN GOES BACK TO BREEZY AND WARM UNDER DRY SOUTHWESTERLY FLOW. SO... TEMPERATURES WILL HEAD BACK UP...AND BREEZY DOWNSLOPE WINDS WILL RETURN. THE WINDS DON'T CURRENTLY LOOK AS STRONG FOR THIS PART OF THE FORECAST AS THEY DO EARLIER IN THE WEEK. LITTLE OR NO PRECIPITATION SEEMS LIKELY IN THE LATE WEEK FORECAST. LW && .PUB WATCHES/WARNINGS/ADVISORIES...NONE. && $$ co AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE PADUCAH KY 647 AM CST SUN MAR 27 2005 .UPDATE... THIS UPDATE IS FOR THE GRIDDED PORTION OF THE FORECAST. FIRST WAVE OF RAIN AND ISOLD TSRA MOVG NE. BACK EDGE WAS MOVG ACROSS SRN ILLINOIS AND WRN KENTUCKY. THE WAVE IS SEEN WELL IN SOUNDER IMAGERY...AND VIA THE BLOOMFIELD WIND PROFILER...AS H5 WINDS THERE HAVE VEERED MORE WSW IN DIRECTION OVER THE PAST FEW HOURS. THE RUC MODEL SEEMS TO HAVE A GOOD HANDLE ON THE SHORT TERM. WE HAVE MODIFIED THE GRIDS TO REFLECT THE LATEST PRECIPITATION TRENDS. HOWEVER...WITH THIS UNSETTLED FLOW PATTERN WELL ESTABLISHED...AND REGIONAL RADAR IMAGERY SHOWING HINTS OF MORE DEVELOPMENT TO OUR WEST AND SOUTH...WILL LEAVE THE ZONE FORECAST PRODUCT AS IS FOR NOW (PERIODS OF RAIN...ISOLD TSRA). RUC SHOWS RAPID NEWARD EXPANSION OF DYNAMICAL FORCING AND ASSOC MOISTURE BETWEEN 18Z-21Z THIS AFTERNOON...JUST NE OF THE UPPER LOW TRACK...WHICH IS STILL FORECAST ACROSS SOUTHERN ARKANSAS THIS AFTN. THIS JIVES WITH CURRENT HIGH END CATEGORICAL POPS ALREADY IN THE GRIDS FOR THE AFTERNOON AND EARLY EVENING. && .PREV DISCUSSION... (ISSUED 320 AM CST SUN MAR 27 2005) WIDESPREAD RAINS ACROSS THE FA EARLY THIS MORNING. A FEW LIGHTNING STRIKES JUST SOUTH OF THE FA. 00Z UPPER AIR ANALYSIS...AND SAT/RADAR TRENDS SUGGEST AN INITIAL LEAD WAVE LIFTING NE ACROSS ARKANSAS EARLY THIS MORNING. REGIONAL RADAR MOSAIC SHOWS A DISTINCT BACK EDGE TO THE LARGE RAIN SHIELD OVER THE AREA. RAINS SHOULD TAPER OFF FROM 09Z-13Z FROM SW TO NE ACROSS THE FA EARLY THIS MORNING. WITH THAT SAID...NEW LIGHT RAIN SHOWERS REDEVELOPING OVER NW/NCNTRL ARKANSAS AS WE SPEAK. SO...DESPITE THE RESPITE EXPECTED IN THE ACTIVITY...WILL KEEP POPS FAIRLY HIGH THROUGH THE DAY...AS THE MAIN UPPER LOW EJECTS E...REACHING SCNTRL ARKANSAS BY EARLY EVENING...PER WVAPOR TRENDS. GOOD FORCING/UVM FIELD NORTH OF THE LOW TRACK SUPPORTS CATEGORICAL POPS...ALTHOUGH PRECIP WILL LIKELY MOVE THROUGH IN WAVES. CONTINUED WITH THUNDER MENTION...BASED ON SIMILAR REASONING FROM PREVIOUS SHIFT. GFS IS DEFINITELY SUGGESTING MORE ELEVATED INSTABILITY WILL BE PRESENT. SEEMS BEST INDICATOR FOR DETERMINING AREA OF ELEVATED INSTABILITY (BASED ON LIGHTNING STRIKES) IS COMPUTING LI'S FROM 800/750MB. THUS...KEEPING A THUNDER MENTION OVER THE SOUTHERN PART OF THE FA...AND ESPECIALLY WEST KY SEEMS WARRANTED. WE EXPECT THE SFC LOW TRACK TO BE MUCH LIKE WHAT WE EXPECTED YESTERDAY...THE LOW REACHING MID TENNESSEE SAY AROUND OR JUST WEST OF NASHVILLE...BY 00Z. GFS/NAM ARE IN PRETTY GOOD AGREEMENT WITH THE SFC LOW TRACK. THE GFS/NAM DO TRACK THE H8 LOW INTO SW KY...AROUND THE PENNYRILE REGION LATE TODAY/THIS EVENING. GFS DOES SHOW DECENT LOW TROP WAA...H8 TEMPS/DWPTS JUMPING UP TO 7-9 DEG C IN THIS AREA. SO WE CANNOT RULE OUT ISOLD STRONG/SVR TSTMS IN THIS AREA...CAPABLE OF PRODUCING A LITTLE HAIL. THE STORM SYSTEM WILL DEPART TONIGHT...BRINGING AND END TO THE RAIN ACROSS THE FA FROM WEST TO EAST. OTHER THAN A CHANCE OF RAIN OVER OUR EASTERN COUNTIES MONDAY MORNING...THE REMAINDER OF THE DAY LOOKS DRY. NO CHANGES TO THE CURRENT FORECAST BEYOND MONDAY. IN TERMS OF TEMPS... EXPECT LITTLE RECOVERY WITH THE CLOUDS AND RAIN TODAY. BEST CHANCE FOR TEMP RISE IS OVER THE PENNYRILE REGION...WHERE SOME WARMER AIR MAY WRAP WESTWARD AND BUMP UP THE MERCURY A FEW DEGREES THERE. A BLEND OF GUIDANCE WAS USED. && .PAH WATCHES/WARNINGS/ADVISORIES... .KY...NONE. .MO...NONE. .IL...NONE. .IN...NONE. && $$ ky AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LAKE CHARLES LA 1004 AM CST SUN MAR 27 2005 .DISCUSSION...UPPER LOW SPINNING OVER NE TX WILL MOVE INTO NRN LA THRU THE DAY. BIT OF A DRY SLOT MOVING INTO SE HAS SHUT OFF ALL RAIN OVER THAT REGION...WITH STILL SOME LIGHT (MAINLY SPRINKLES) OVER THE LA PARISHES. WILL CONTINUE TO SEE WRAP AROUND CLOUDS WITH THIS SYSTEM SO LOOKING FOR A COOL DAY ACROSS THE REGION. WILL HOLD ONTO CHANCE OF LIGHT RAIN MAINLY OVER NRN ZONES FOR THIS AFTERNOON BUT NOT OVER NRN ZONES. MODERATE WEST-NW WINDS WILL CONTINUE THIS AFTERNOON BUT SHOULD STAY BELOW LAKE WIND ADVISORIES. HAVE LOWERED TEMPS A FEW DEGREES ACROSS THE AREA AS COLD AIR ADVECTION AND CLOUDS WILL KEEP TEMPS HOLDING STEADY FOR TODAY. HAVE UPDATED THE GRIDS AND WILL HAVE ZONES OUT SHORTLY. WILEY && .AVIATION...MAINLY MVFR CIGS FOR TODAY WITH LIGHT RAIN POSSIBLE AT KAEX...BUT ALL THUNDERSTORM ACTIVITY HAS EXITED THE REGION. && .MARINE...SEE DISCUSSION BELOW. && .PREV DISCUSSION... (ISSUED 745 AM CST SUN MAR 27 2005) UPDATE...SEVERE THUNDERSTORM WATCH WILL BE ALLOWED TO EXPIRE AT 8 AM. WILL UPDATE ZONES AND COASTAL FORECAST TO REMOVE WATCH HEADLINE AND SEVERE WORDING. AREA OF MAINLY SHOWERS CONTINUES TO MOVE NORTHEAST ACROSS THE CWA...AND EXPECT THIS ACIVITY TO DIMINISH THROUGH THE MORNING HOURS. PREV DISCUSSION... DISCUSSION...STRONG TO SEVERE THUNDERSTORMS MOVING ACROSS THE HOUSTON AREA THIS MORNING HAVE PROMPTED THE ISSUANCE OF A SEVERE THUNDERSTORM WATCH UNTIL 8 AM FOR THE ENTIRE AREA. THESE STORMS HAVE HAD A HISTORY OF PRODUCING GOLF BALL SIZE HAIL...HOWEVER THEY SEEM TO BE WEAKENING AS THEY APPROACH THE WESTERN PORTIONS OF THE CWA. RUC INDICATES AN UPPER LEVEL JET MAX OF 126 KT ROTATING AROUND THE BASE OF THE UPPER LOW INTO SE TX...WHICH APPEARS TO BE AIDING IN DEVELOPMENT OF THESE STORMS. THE UPPER LOW IS CURRENTLY LOCATED OVER N CENTRAL TX AND WILL BE MOVING EAST TODAY. AT THE SURFACE...LOW PRESSURE IS LOCATED NE OF JAN WITH THE COLD FRONT EXTENDING SOUTHWEST ACROSS SE LA AND INTO THE NORTHERN GULF. BESIDES DEALING WITH THIS MORNING'S SEVERE WEATHER...THE MAIN FORECAST ISSUE FOR TODAY IS CLOUDS AND TEMPS. ETA AND GFS INDICATE MOISTURE LINGERING THROUGH 06Z MONDAY...ESPECIALLY ACROSS THE NORTHERN ZONES. AFTERNOON TEMPS WILL DEPEND ON HOW LONG THE CLOUDS HANG AROUND. CURRENTLY PLAN TO GO A BIT BELOW MAV GUIDANCE SINCE EXPECT CLOUDS THROUGH MOST OF THE AFTERNOON. OVERNIGHT LOWS WILL BE BELOW NORMAL MONDAY AND TUESDAY MORNING WITH CLEAR SKIES AND WEAK WINDS ALLOWING RADIATIONAL COOLING TO MAXIMIZE. WILL BEGIN TO SEE RETURN FLOW FROM THE GULF ON TUESDAY WITH MOISTURE RETURNING TO THE AREA ON WEDNESDAY. NEXT CHANCE OF SHOWERS AND THUNDERSTORMS WILL BE THURSDAY AND FRIDAY AS THE NEXT FRONT MAKES ITS WAY ACROSS THE AREA. LOOKS LIKE BEST UPPER LEVEL SUPPORT WITH THIS SYSTEM WILL BE NORTH OF THE AREA...BUT WILL MONITOR DURING THE WEEK. DRY WEATHER WILL RETURN FOR NEXT WEEKEND. AVIATION...MVFR TO IFR CONDITIONS ACROSS THE AREA THIS MORNING MAINLY DUE TO LOW CEILINGS ACROSS THE AREA. LOWEST CIGS AROUND 1000 FT OVER S CENTRAL LA. SHOWERS AND THUNDERSTORMS WILL MOVE ACROSS THE AREA DURING THE MORNING HOURS. CONDITIONS SHOULD BE IMPROVING THIS AFTERNOON...BECOMING CLEAR BY TONIGHT. MARINE...STRONG NORTHERLY WINDS WILL CONTINUE OVER THE COASTAL WATERS. WINDS WILL BE AROUND 20 TO 25 KNOTS...WITH SEAS AROUND 5 TO 7 FEET. WINDS WILL SUBSIDE MONDAY...BECOMING SOUTHERLY BY TUESDAY AS HIGH PRESSURE MOVES EAST. && .PRELIMINARY POINT TEMPS/POPS... KLCH 59 45 72 49 / 30 0 0 0 KBPT 59 44 72 49 / 30 0 0 0 KAEX 57 43 71 48 / 50 0 0 0 KLFT 59 44 72 48 / 30 0 0 0 && LCH WATCHES/WARNINGS/ADVISORIES... LA...SCA GMZ450-455-470-475. TX...SCA GMZ450-470. && $$ la AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SHREVEPORT LA 1000 AM CST SUN MAR 27 2005 .DISCUSSION... WATER VAPOR IMAGERY SHOWS TROUGH CURRENTLY OVER NE TX...LUMBERING SLOWLY TOWARD KSHV...WITH A SECOND BATCH OF MODERATE RAIN AHEAD OF IT. THIS TRANSLATES INTO A WET...COOL...OVERCAST EASTER...WHICH IS COVERED WELL IN THE GRIDS. NO UPDATE. && .PREV DISCUSSION... (ISSUED 245 AM CST SUN MAR 27 2005) DISCUSSION... ALTHOUGH MUCH OF THE AREA FAILED TO RECORD RAIN DESPITE THE POTENTIAL FOR STRONG THUNDERSTORM DEVELOPMENT...AT LEAST AN EXPANDING AREA OF WIDESPREAD SHOWERS LOOKS EMMINENT TO ENGULF MUCH OF THE AREA LATE TONIGHT ACROSS EAST TEXAS...AND SPREAD INTO LA...AND TO SOME EXTENT...OK/AR PORTIONS OF AREA DURING THE MORNING. MOST THUNDERSTORMS CONFINED TO NEAR COASTLINE FOR NOW...BUT PUT IN EMBEDDED THUNDER SOUTHERN PORTIONS THIS MORNING...AS RUC INDICATES SIGNIFICANT SPEED DIVERGENCE IN UPPER FLOW SOUTH OF INTERSTATE 20. SHOULD SEE ALL PRECIP CLEAR THE AREA BY LATE THIS AFTERNOON...WITH OVERCAST DECK JUST STARTING TO ERODE OVER WESTERN SECTIONS BY THEN. WITH GUSTY NW WINDS CONTINUING MOST OF THE DAY...CLOUDS AND WIND WITH TEMPS RISING LITTLE FROM OVERNIGHT LOWS...RATHER GLOOMY FOR AN EASTER SUNDAY BUT AT LEAST MINIMAL THREATENING WEATHER IN ARKLATEX. SMALL HAIL COULD BE NOTED IN STRONGER CELLS DUE TO STRONG UPPER DIVERGENCE AND COOL TEMPS. HOWEVER...INSTABILITY WILL BE EASILY ELEVATED. SOUTHERLY FLOW WILL GET GOING MONDAY NIGHT...ALTHOUGH BOUNDARY LAYER MOISTURE RETURN LOOKING MINIMAL AT FIRST. THUS...WILL TAKE A FULL COUPLE OF DAYS OF SOUTHERLY FLOW TO EVEN PRODUCE MARGINAL MOISTURE FOR CONVECTION AS UPPER LOW PASSES JUST NORTH OF AREA. PUT IN CHANCE NORTH...NEAR LOW AND ONLY SLIGHT CHANCE ELSEWHERE...FOR WED NIGHT AND THURSDAY. AIR THEN LOOKING VERY DRY FOR WEEKEND... WHICH SHOULD BE WELCOME...AS LONG AS AREA GETS SOME NEEDED RAIN BEFORE THEN. && .PRELIMINARY POINT TEMPS/POPS... SHV 54 41 71 50 / 70 0 0 0 MLU 56 41 69 47 / 70 0 0 0 DEQ 48 36 71 48 / 50 0 0 0 TXK 52 39 70 50 / 70 0 0 0 ELD 52 39 69 47 / 70 0 0 0 TYR 50 39 73 53 / 70 0 0 0 GGG 53 39 72 52 / 70 0 0 0 LFK 56 39 72 53 / 90 0 0 0 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...NONE. LA...NONE. OK...NONE. TX...NONE. && $$ 17/44 la AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE LAKE CHARLES LA 745 AM CST SUN MAR 27 2005 .UPDATE...SEVERE THUNDERSTORM WATCH WILL BE ALLOWED TO EXPIRE AT 8 AM. WILL UPDATE ZONES AND COASTAL FORECAST TO REMOVE WATCH HEADLINE AND SEVERE WORDING. AREA OF MAINLY SHOWERS CONTINUES TO MOVE NORTHEAST ACROSS THE CWA...AND EXPECT THIS ACIVITY TO DIMINISH THROUGH THE MORNING HOURS. && .PREV DISCUSSION... .DISCUSSION...STRONG TO SEVERE THUNDERSTORMS MOVING ACROSS THE HOUSTON AREA THIS MORNING HAVE PROMPTED THE ISSUANCE OF A SEVERE THUNDERSTORM WATCH UNTIL 8 AM FOR THE ENTIRE AREA. THESE STORMS HAVE HAD A HISTORY OF PRODUCING GOLF BALL SIZE HAIL...HOWEVER THEY SEEM TO BE WEAKENING AS THEY APPROACH THE WESTERN PORTIONS OF THE CWA. RUC INDICATES AN UPPER LEVEL JET MAX OF 126 KT ROTATING AROUND THE BASE OF THE UPPER LOW INTO SE TX...WHICH APPEARS TO BE AIDING IN DEVELOPMENT OF THESE STORMS. THE UPPER LOW IS CURRENTLY LOCATED OVER N CENTRAL TX AND WILL BE MOVING EAST TODAY. AT THE SURFACE...LOW PRESSURE IS LOCATED NE OF JAN WITH THE COLD FRONT EXTENDING SOUTHWEST ACROSS SE LA AND INTO THE NORTHERN GULF. BESIDES DEALING WITH THIS MORNING'S SEVERE WEATHER...THE MAIN FORECAST ISSUE FOR TODAY IS CLOUDS AND TEMPS. ETA AND GFS INDICATE MOISTURE LINGERING THROUGH 06Z MONDAY...ESPECIALLY ACROSS THE NORTHERN ZONES. AFTERNOON TEMPS WILL DEPEND ON HOW LONG THE CLOUDS HANG AROUND. CURRENTLY PLAN TO GO A BIT BELOW MAV GUIDANCE SINCE EXPECT CLOUDS THROUGH MOST OF THE AFTERNOON. OVERNIGHT LOWS WILL BE BELOW NORMAL MONDAY AND TUESDAY MORNING WITH CLEAR SKIES AND WEAK WINDS ALLOWING RADIATIONAL COOLING TO MAXIMIZE. WILL BEGIN TO SEE RETURN FLOW FROM THE GULF ON TUESDAY WITH MOISTURE RETURNING TO THE AREA ON WEDNESDAY. NEXT CHANCE OF SHOWERS AND THUNDERSTORMS WILL BE THURSDAY AND FRIDAY AS THE NEXT FRONT MAKES ITS WAY ACROSS THE AREA. LOOKS LIKE BEST UPPER LEVEL SUPPORT WITH THIS SYSTEM WILL BE NORTH OF THE AREA...BUT WILL MONITOR DURING THE WEEK. DRY WEATHER WILL RETURN FOR NEXT WEEKEND. AVIATION...MVFR TO IFR CONDITIONS ACROSS THE AREA THIS MORNING MAINLY DUE TO LOW CEILINGS ACROSS THE AREA. LOWEST CIGS AROUND 1000 FT OVER S CENTRAL LA. SHOWERS AND THUNDERSTORMS WILL MOVE ACROSS THE AREA DURING THE MORNING HOURS. CONDITIONS SHOULD BE IMPROVING THIS AFTERNOON...BECOMING CLEAR BY TONIGHT. MARINE...STRONG NORTHERLY WINDS WILL CONTINUE OVER THE COASTAL WATERS. WINDS WILL BE AROUND 20 TO 25 KNOTS...WITH SEAS AROUND 5 TO 7 FEET. WINDS WILL SUBSIDE MONDAY...BECOMING SOUTHERLY BY TUESDAY AS HIGH PRESSURE MOVES EAST. && .LCH WATCHES/WARNINGS/ADVISORIES... LA...SCA GMZ450-455-470-475. TX...SCA GMZ450-470. && $$ la AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE LAKE CHARLES LA 550 AM CST SUN MAR 27 2005 .UPDATE...HAVE UPDATED ZFP AND CWF TO REMOVE SEVERE THUNDERSTORM WATCH FROM SOUTHEAST TEXAS ZONES AS WELL AS THE COASTAL WATERS OUT TO 20 NM FROM CAMERON TO HIGH ISLAND. AN AREA OF RAIN WITH EMBEDDED THUNDERSTORMS CONTINUES TO MOVE NORTHEAST. MOST OF THE ACTIVITY HAS WEAKENED...WITH THE STRONGEST STORM NOW MOVING ACROSS CENTRAL LA. && .PREV DISCUSSION...STRONG TO SEVERE THUNDERSTORMS MOVING ACROSS THE HOUSTON AREA THIS MORNING HAVE PROMPTED THE ISSUANCE OF A SEVERE THUNDERSTORM WATCH UNTIL 8 AM FOR THE ENTIRE AREA. THESE STORMS HAVE HAD A HISTORY OF PRODUCING GOLF BALL SIZE HAIL...HOWEVER THEY SEEM TO BE WEAKENING AS THEY APPROACH THE WESTERN PORTIONS OF THE CWA. RUC INDICATES AN UPPER LEVEL JET MAX OF 126 KT ROTATING AROUND THE BASE OF THE UPPER LOW INTO SE TX...WHICH APPEARS TO BE AIDING IN DEVELOPMENT OF THESE STORMS. THE UPPER LOW IS CURRENTLY LOCATED OVER N CENTRAL TX AND WILL BE MOVING EAST TODAY. AT THE SURFACE...LOW PRESSURE IS LOCATED NE OF JAN WITH THE COLD FRONT EXTENDING SOUTHWEST ACROSS SE LA AND INTO THE NORTHERN GULF. BESIDES DEALING WITH THIS MORNING'S SEVERE WEATHER...THE MAIN FORECAST ISSUE FOR TODAY IS CLOUDS AND TEMPS. ETA AND GFS INDICATE MOISTURE LINGERING THROUGH 06Z MONDAY...ESPECIALLY ACROSS THE NORTHERN ZONES. AFTERNOON TEMPS WILL DEPEND ON HOW LONG THE CLOUDS HANG AROUND. CURRENTLY PLAN TO GO A BIT BELOW MAV GUIDANCE SINCE EXPECT CLOUDS THROUGH MOST OF THE AFTERNOON. OVERNIGHT LOWS WILL BE BELOW NORMAL MONDAY AND TUESDAY MORNING WITH CLEAR SKIES AND WEAK WINDS ALLOWING RADIATIONAL COOLING TO MAXIMIZE. WILL BEGIN TO SEE RETURN FLOW FROM THE GULF ON TUESDAY WITH MOISTURE RETURNING TO THE AREA ON WEDNESDAY. NEXT CHANCE OF SHOWERS AND THUNDERSTORMS WILL BE THURSDAY AND FRIDAY AS THE NEXT FRONT MAKES ITS WAY ACROSS THE AREA. LOOKS LIKE BEST UPPER LEVEL SUPPORT WITH THIS SYSTEM WILL BE NORTH OF THE AREA...BUT WILL MONITOR DURING THE WEEK. DRY WEATHER WILL RETURN FOR NEXT WEEKEND. && .AVIATION...MVFR TO IFR CONDITIONS ACROSS THE AREA THIS MORNING MAINLY DUE TO LOW CEILINGS ACROSS THE AREA. LOWEST CIGS AROUND 1000 FT OVER S CENTRAL LA. SHOWERS AND THUNDERSTORMS WILL MOVE ACROSS THE AREA DURING THE MORNING HOURS. CONDITIONS SHOULD BE IMPROVING THIS AFTERNOON...BECOMING CLEAR BY TONIGHT. && .MARINE...STRONG NORTHERLY WINDS WILL CONTINUE OVER THE COASTAL WATERS. WINDS WILL BE AROUND 20 TO 25 KNOTS...WITH SEAS AROUND 5 TO 7 FEET. WINDS WILL SUBSIDE MONDAY...BECOMING SOUTHERLY BY TUESDAY AS HIGH PRESSURE MOVES EAST. && .PRELIMINARY POINT TEMPS/POPS... KLCH 62 45 72 49 / 30 0 0 0 KBPT 60 44 72 49 / 30 0 0 0 KAEX 58 43 71 48 / 50 0 0 0 KLFT 62 44 72 48 / 30 0 0 0 && .LCH WATCHES/WARNINGS/ADVISORIES... LA...SVR TSTM WATCH 95 LAZ027>033-041-042-051-043>045-052>055 TX...NONE. SCA GMZ450-455-470-475. && $$ la AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 1045 AM EST SAT MAR 27 2005 .DISCUSSION... MAIN UPDATE CONCERN IS TEMPERATURES CURRENT WEATHER...15Z WATER VAPOR LOOP AND 12Z RAOBS SHOWED SPLIT FLOW ACROSS THE COUNTRY WITH A NEARLY ZONAL NORTHERN STREAM ALONG THE U.S./CANADIAN BORDER. MUCH MORE ACTIVE SOUTHERN STREAM... ESPECIALLY OVER THE SOUTHEAST U.S....WHERE A TROUGH IS LOCATED OVER THE SOUTHERN MISSISSIPPI VALLEY. IN THE NORTHERN STREAM....UPPER LEVEL MOISTURE CAN BE SEEN SPREADING FROM THE EAST PACIFIC ACROSS THE NORTHERN PLAINS INTO THE MN ARROWHEAD. VIS SATELLITE IMAGERY ALSO SHOWS BY A THICK AREA OF CIRRUS COVERING NORTH DAKOTA AND NORTHERN MN. SKIES REMAIN NEARLY CLEAR THOUGH OVER UPPER MICHIGAN...WHICH WITH THE STRONGER LATE MARCH SUNSHINE HAS ALLOWED TEMPERATURES TO QUICKLY CLIMB INTO THE LOW TO MID 40S AWAY FROM LAKE MICHIGAN. A SHRTWV COULD BE SEEN IN THE WATER VAPOR IMAGERY ON THE NORTH SIDE OF THE CIRRUS SHIELD IN SOUTHERN MANITOBA. THIS SHRTWV HAS ALLOWED A SURFACE LOW TO DEVELOP NEAR LAKE WINNIPEG...WITH A WARM FRONT EXTENDING EASTWARD TO JUST NORTH OF LAKE SUPERIOR. TO THE SOUTH OF THE FRONT...CONDITIONS ARE QUITE DRY AS INDICATED BY BOTH THE 12Z INL AND GRB SOUNDINGS. 12Z SOUNDING FROM GRB ALSO SHOWED A NEARLY MIXED LAYER FROM 825MB TO 975MB...WHICH IS ALSO HELPING IN THE TEMPERATURES TO RISE QUICKLY. THE 850MB TEMP AT GRB WAS -3C...WHICH IS 1 TO 2C HIGHER THAN YESTERDAY. THIS AFTERNOON...HIGH CLOUDS SHOULD CONTINUE TO SPREAD INTO UPPER MICHIGAN...ESPECIALLY IN THE WEST...WHICH BOTH THE NAM AND RUC INDICATE. IN FACT BY 00Z...SKIES MAY END UP BEING COMPLETELY CLOUDY IN IWD. FOR THE REST OF THE U.P. THOUGH...EXPECT GENERALLY MOSTLY SUNNY SKIES. WITH 850MB TEMPS A FEW DEGREES WARMER THAN YESTERDAY...EXPECT THE SAME THING TO OCCUR WITH HIGH TEMPERATURES. HAVE BUMPED UP HIGHS ABOUT 5 DEGREES FROM MARQUETTE-MENOMINEE WESTWARD. NO CHANGE IN THE EAST WHERE SOUTH WINDS COMING OFF OF LAKE MICHIGAN WILL HOLD TEMPERATURES DOWN...ESPECIALLY ALONG US-2. PREV DISCUSSION (TONIGHT THROUGH TUE NIGHT)... THE MANITOBA SHORTWAVE WILL RACE ACROSS ONTARIO STAYING JUST TO THE NORTH OF LAKE SUPERIOR. THE NOSE OF THE 100KT UPPER LEVEL JET WILL TRACK ALONG THE NORTH SHORE OF THE U.P. TOGETHER THIS SHOULD PRODUCE INSTABILITY OVER NORTHERN LAKE SUPERIOR. THE SOUTHERN SURFACE LOW WILL PUSH NORTHEAST INTO EASTERN KENTUCKY WHILE THE RIDGE WILL REMAIN OVER LOWER MICHIGAN. THE WEAK SURFACE LOW OVER MANITOBA WILL PUSH INTO NORTHERN LAKE SUPERIOR. THE MEAN 900-800MB RH WILL INCREASE TO 90 PERCENT OVER CENTRAL ONTARIO...AND TO AROUND 70 PERCENT OVER NORTHERN LAKE SUPERIOR. THERE WILL THEN BE A POTENTIAL FOR SOME LIGHT RAIN OR SNOW OVER LAKE SUPERIOR. THE MORE STABLE DRIER CONDITIONS OVER UPPER MICHIGAN SHOULD KEEP CONDITIONS DRY. HOWEVER...SKY COVER SHOULD INCREASE OVER THE FORECAST AREA. THUS TEMPERATURES WILL BE MODERATED BY THE CLOUD COVER. THE SHORTWAVE OVER NORTHERN LAKE SUPERIOR WILL SHIFT INTO WESTERN QUEBEC ON MONDAY AS A WEAKER SHORTWAVE SHIFTS INTO WESTERN LAKE SUPERIOR AND WESTERN U.P. ANOTHER SHORTWAVE WILL DEEPEN OVER THE NORTHERN HIGH PLAINS. THE SURFACE LOW WILL WEAK EVEN MORE AS IT RELOCATES OVER EAST CENTRAL ONTARIO AS THE KENTUCKY LOW MOVE TO THE MIDDLE EASTERN ATLANTIC STATES. A SURFACE LOW ASSOCIATED WITH THE HIGH PLAINS SHORTWAVE WILL ALSO DEEPEN AND MOVE INTO WESTERN DAKOTAS. COLD AIR WRAPPING IN BEHIND THIS SYSTEM WILL HELP TO DEVELOP A COLD FRONT ACROSS THE HIGH PLAINS. WINDS WILL REMAIN OUT OF THE SOUTH OVER THE AREA ON MONDAY KEEPING WARM AIR ADVECTION OVER THE AREA AND INCREASING THE LOW LEVEL RH. NAM(ETA) DEVELOPS A WARM FRONT OVER IOWA ON MONDAY WHILE THE CANADIAN COLD FRONT SETTLES INTO NORTHERN LAKE SUPERIOR. WARM MOIST AIR OVERRUNNING THE WARM FRONT WILL PRODUCE CLOUDS OVER THE FORECAST AREA ON MONDAY LIMITING HEATING. MOST OF THE INSTABILITY AND MOISTURE WILL STAY NORTH AND WEST OF THE FORECAST AREA SO DO NOT EXPECT TO SEE PRECIPITATION. THE SHORTWAVE OVER THE WESTERN U.P. WILL MOVE INTO EASTERN ONTARIO MONDAY NIGHT AS THE CENTRAL PLAINS SHORTWAVE DEEPENS OVER THE DAKOTAS AND NORTH MINNESOTA. THE SURFACE LOW WILL SHIFT INTO SOUTHERN MANITOBA DRAGGING THE COLD FRONT INTO NORTHWEST MINNESOTA AND THE CENTRAL PLAINS. THE WARM FRONT WILL MOVE OVER THE U.P. A STRONG SOUTHERLY FLOW AHEAD OF THE COLD FRONT WILL DRAW WARM MOIST AIR INTO THE FORECAST AREA. OVERRUNNING OF THE WARM FRONT WILL PRODUCE SOME LIGHT RAIN OVER THE WESTERN U.P. MONDAY NIGHT. THE SHORTWAVE WILL MOVE OVER THE FORECAST AREA ON TUESDAY AS THE DEEPER SHORTWAVE DEEPEN OVER THE NORTH CENTRAL PLAINS. THE SURFACE LOW WILL MOVE INTO THE CENTRAL U.P. DRAGGING THE COLD FRONT INTO THE U.P. AN UPPER LEVEL JET MAX WILL MOVE OUT THE CENTRAL PLAINS INTO IOWA...PLACING THE FORECAST AREA UNDER THE LEFT EXIT REGION OF THE 110KT MAX. THIS SHOULD INCREASE THE POTENTIAL FOR SHOWERS AND POSSIBLY A THUNDERSTORM OVER THE AREA. THE NORTH CENTRAL PLAINS SHORTWAVE WILL DEEPEN OVER THE FORECAST AREA ON TUESDAY NIGHT. THE SURFACE LOW WILL MOVE ACROSS THE WESTERN END OF THE FORECAST AREA INTO EASTERN ONTARIO DRAGGING THE COLD FRONT WITH IT. THE UPPER LEVEL JET MAX WILL MOVE INTO SOUTHERN LOWER MICHIGAN. INSTABILITY ASSOCIATED WITH THE SHORTWAVE WILL CONTINUE TO GENERATE SHOWERS. THE 925MB TEMPERATURES WILL BE AROUND 1C...WARM ENOUGH TO KEEP PRECIPITATION IN THE FORM OF RAIN. && .MQT...WATCHES/WARNINGS/ADVISORIES...NONE. && $$ AJ (SHORT TERM) DLG (PREV DISCUSSION) mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 345 PM EST SAT MAR 27 2005 .DISCUSSION... 12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW SPLIT FLOW ACRS NAMERICA WITH FA ON SRN FRINGE OF WLY FLOW ALF TO THE S OF NRN BRANCH TROF OVER HUDSON BAY. AT THE SFC...WX OVER THE UPR GRT LKS REMAINS DOMINATED BY WSE-ENE ORIENTED RDG AXIS EXTENDING ACRS THE SCNTRL GRT LKS. AIRMASS OVER THE RDG IS QUITE DRY PER 12Z INL/MPX/ GRB SDNGS. WSW LLVL FLOW BTWN THE RDG AND SFC LO NR LK WINNIPEG ASSOCIATED WITH FAIRLY POTENT SHRTWV DRIVING EWD THRU SCNTRL CAN ON SRN PERIPHERY OF THE NRN BRANCH FLOW IS ADVECTING THE DRIER (AND WARMER) AIR INTO THE FA. WITH PLENTY OF SUNSHINE SFC TEMPS THIS AFTN HAVE REACHED 50 AT SOME PLACES. ALTHOUGH 12Z H7 DEWPOINT DEPRESSION 17C AT BOTH INL/BIS...QUITE A BIT OF MID/HI CLD OVER THE NRN PLAINS ACCOMPANYING THE SHRTWV MOVING THRU SRN CAN. SOME OF THIS HI CLD IS SPILLING INTO THE FA. AIR IS DRY ENUF THAT ALL PCPN ACCOMPANYING THE SHRTWV IS CONFINED TO SRN CAN MAINLY ON THE COLD SIDE OF THE SFC LO TRACK. MORE SGNFT MSTR CONFINED TO SRN BRANCH FLOW DOMINATING THE SCNTRL CONUS. A SERIES OF SHRTWVS WITHIN TROF NOW APRCHG THE PAC NW. MAIN FCST CONCERNS THRU MON ARE MAINLY TEMPS. FOCUS THEN BEGINS TO SHIFT TO PCPN CHCS BEGINNING MON NGT. FOR TNGT...MODELS MOVE THE SHRTWV NOW APRCHG LK WINNIPEG ESEWD ACRS ONTARIO JUST N OF LK SUP. CONSIDERING THE TRACK OF THE SFC LO ACRS NRN LK SUP AND THE PASSAGE OF THE BEST DPVA/H85-5 QVECTOR CNVGC TO THE N OF THE FA AS WELL AS THE VERY DRY LO MID TROP IN PLACE AND UPSTREAM...WL RESTRICT MENTION OF PCPN TO THE NRN HALF OF LK SUP AS IN GOING FCST EVEN THOUGH GFS STUBBORNLY INSISTS ON GENERATING PCPN OVER THE NRN TIER ZNS. EVEN THOUGH PCPN WL STAY TO THE N...THE EXTENSIVE MID/HI CLD UPSTREAM WL MOVE OVER THE FA TNGT. CONSIDERING THE STEADY SW WIND FCST BY THE NAM/GFS AND THE EXPECTED OVC MID/HI CLD...WL GO AOA THE WARM SIDE OF MOS GUIDANCE FOR LO TEMPS TNGT. GOING FCST TMINS LOOK ON TRACK. FA WL BE DOMINATED BY H5 HGT RISES ON MON IN DNVA BEHIND SHRTWV FCST TO MOVE INTO QUEBEC. ASSOCIATED SUBSIDENCE SHOULD THIN MID/HI CLD. OVER INLAND AREAS...EXPECT TMAX TO REACH WELL INTO THE 50S AS DETERMINED BY MIXING TO INVRN BASE ON ETA FCST SDNGS. DESPITE INCRSG SUNSHINE...FORMATION OF MESO HIGHS OVER THE COLDER GRT LKS WITH WEAKENING MSLP GRADIENT WL LIKELY CAUSE LK BREEZE FORMATION/ MODERATION AS SFC HTG INLAND DRIVES A HEALTHY LK BREEZE CIRCULATION IN THE AFTN. SHARPENING UPR RDG AXIS BTWN DEEPENING TROFS OVER THE W AND ALG THE E COAST PROGGED TO PUSH OVER THE FA MON NGT. ALTHOUGH ISENTROPIC LIFT PROGGED TO COMMENCE DURING THE NGT...LLVL AIRMASS IS SO DRY AND MAINTAINED BY LLVL SSE TRAJECTORIES THAT THE ONLY IMPACT WL BE AN INCRS IN MID/HI CLD OVERNGT. HAVE DISREGARDED GFS QPF AND WENT WITH A DRY FCST. DESPITE THE DRYNESS OF THE AIR...SHARPENING PRES GRADIENT/INCRSG SLY FLOW WL LIMIT DIURNAL TEMP FALL. MODLES SHOW NEGATIVELY TILTED SRN BRANCH SHRTWV BEGINNING TO LIFT NEWD FM THE SRN ROCKIES ON TUE. DESPITE IMPRESSIVE SLY FLOW BTWN THIS SHRTWV AND HI PRES RDG MOVING TO THE E...GLFMEX TAP REMAINS QUITE LIMITED. DUE TO DVLPG DOWNSTREAM BLOCKING PATTERN...SLOWER 12Z UKMET/00Z ECMWF ARE FVRD. NEW UKMET SHOWS H85 DWPT REMAINING AS LOW AS -10C OVER THE ERN ZNS EVEN AT 00Z WED...WITH DWPT NOT EVEN +4C AT IWD. UKMET GENERATES NO PCPN OVER THE FA (GFS DOES OVER THE WRN ZNS...BUT HAS AXIS OF H85 DWPT UP TO 6C CONVERGING INTO THE WRN ZNS BY 00Z). WL RETAIN A LO CHC POP FOR ONLY THE WRN ZNS IN THE AFTN. ALTHOUGH LO-MID TROP WL REMAIN QUITE DRY...THERE WL BE EXTENSIVE HIER CLD. THID CLD AND LLVL SE FLOW OUT OF HI PRES RDG TO THE E WL RESTRICT DIURNAL TEMP RECOVERY ESPECIALLY DOWNWIND OF LK MI. SUSPECT HI TEMPS WL REACH WELL INTO THE 50S OVER THE WRN ZNS WHERE FCST SSE FLOW DOWNSLOPES (NAM SHOWS 1K FT WIND INCRSG TO AS HI AS 35KT AT IWD IN AFTN). WL ALLOW CHC POPS TO OVERSPRD THE FA TUE NGT AS SRN BRANCH SHRTWV GRINDS NEWD. IN THE MEDIUM/EXTENDED RANGE...HAVE OPTED TO FOLLOW THE MORE CONSISTENT 00Z/12Z ECMWF...WHICH HAS EXCELLENT SUPPORT FM THE GFS REFCST ENSEMBLE MEAN GUIDANCE AND LATEST UKMET RUNS. ECMWF SHOWS UNPHASED SRN BRANCH LO LIFTING NEWD TO NW WI BY WED EVNG...AND THEN ACRS MQT AT 12Z THU TO JUST S OF JAMES BAY BY THU EVNG. SYS DOES NOT HAVE A GREAT GLFMEX CONNECTION (H85 DWPT FCST UP TO 5-6C ON WED)...BUT WL BUMP POPS UP TO LIKELY ON WED AFTN UNDER FAIRLY IMPRESSIVE DIFFLUENT FLOW ALF. EVEN SO...THINK LIMITED LLVL MSTR WL LESSEN THE THREAT OF HVY RA DESPITE THE VIGOROUS DYNAMICS. FA FCST TO BE IN CYC FLOW ON THU WITH MODERATELY CHILLY AIR (H85 TEMPS DOWN TO ARND -3C)...SO WL GO WITH SCT -SHRASN. THEN DRY AND SEASONABLE ON FRI AND SAT WITH SFC HI PRES RDG BLDG TOWARD THE AREA TO THE W OF DEEPENING UPR TROF OVER THE E. COORDINATED WITH APX/GRB/DLH. && .MQT...WATCHES/WARNINGS/ADVISORIES...NONE. && $$ KC mi AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC 442 PM EST SUN MAR 27 2005 .SHORT TERM (REST OF TONIGHT)... WILL SEND OUT A QUICK UPDATE FOR SVR TSTRM WATCH #99. && .PREVIOUS DISCUSSION... (ISSUED 325 PM EST SUN MAR 27 2005) SHORT TERM (TONIGHT THROUGH WEDNESDAY)... A SEVERE WEATHER WATCH BOX LOOMS OMINOUSLY TO THE WEST OF OUR CWFA...ONE COUNTY AWAY FROM OUR NORTHEAST GEORGIA WARNING UMBRELLA. KFFC 88-D HAS SHOWN A RAPID GROWTH OF CONVECTION THIS AFTERNOON AS MISSISSIPPI VALLEY SYSTEM BEGINS SHIFTING EASTWARD. THE GEORGIA CONVECTION IS LIFTING NORTHEAST RAPIDLY...AND FORWARD SPEEDS COULD CONTINUE TO INCREASE THIS EVENING AS UPPER FLOW AMPLIFIES. THERE HAS BEEN SOME LARGE HAIL UPSTREAM...UNDER THE MUCH STEEPER LAPSE RATES ASSOCIATED WITH BROAD SWATH OF DRIER MID LEVEL AIR. FARTHER SOUTHWEST...TORNADIC SUPERCELLS WERE DEVELOPING. DURING THE OVERNIGHT HOURS...DIRECTIONAL SHEAR PROFILES ON FORECAST SOUNDINGS AT THEIR BEST THROUGH 06Z...THEN ESPECIALLY THE LOW LEVEL FLOW PROGD TO VEER SIGNIFICANTLY SO THAT DIRECTIONAL SHEAR IS NOT AS GREAT. CWFA REMAINS STABLE AND WEDGED FOR THE MOST PART...ALTHOUGH STEADY RISES IN TEMPERATURE AND DEWPOINTS HAVE BEEN OBSERVED WITHIN THE DAMMING REGION...EVEN AS DRIZZLE AND PERIODS OF LIGHT RAIN HAVE AFFECTED THE NORTH. AS THE APPROACHING GEORGIA CONVECTION ENCOUNTERS THE COOLER AND STABLE AIR OVER OUR AREA...INITIAL WEAKENING WOULD BE EXPECTED. THE ARRIVAL OF THE BROAD CONVECTIVE AREA IN THE NEXT COUPLE OF HOURS WILL HASTEN THE DEMISE OF THE STABLE WEDGE OF AIR FOR NORTHEAST GEORGIA AND THE WESTERN UPSTATE. INTERIOR DAMMING REGION LOCATIONS...HOWEVER...AND ESPECIALLY THE NORTHERN FOOTHILLS AND NORTHWEST PIEDMONT...WILL LIKELY MAINTAIN THE WEDGE UNTIL SCOURING OCCURS LATE TONITE. EASTERN ZONES...AND THOSE SOUTHEAST ZONES BORDERING THE COLUMBIA FOREAST AREA OF RESPONSIBILITY...COULD ALSO SEE SIGNIFICANT EROSION OF THE STABLE COOL LAYER IN THE NEXT LITTLE WHILE. THE THERMAL MOISTURE BOUNDARY HAS WORKED WELL INTO THE MIDLANDS...WITH LOWER 60 DEWPOINTS NOT FAR TO OUR EAST OR SOUTH. THE WINDOW IS CLOSING...BUT THERE IS STILL TIME TO ERODE PART OF THE WEDGE FOR OUR SOUTHERN PIEDMONT OF NORTH CAROLINA AND THE EASTERN PIEDMONT OF SOUTH CAROLINA. IT WILL BE INTERESTING TO SEE WHAT TRANSPIRES TO OUR SURFACE FEATURES DURING THE NEXT TWO TO THREE HOURS. IF THE APPROACHING GEORGIA CONVECTION DOES NOT ERODE THE WEDGE...WHICH WE THOUGHT WAS POSSIBLE EARLIER BUT NOT SO CONFIDENT NOW...AND IF THE THERMAL MOISTURE BOUNDARY DOES NOT ERODE THE WEDGE ON OUR EASTERN AND SOUTHEAST PERIPHERY...THEN IT IS LIKELY THAT THE WEDGE WILL HOLD UNTIL EROSION IS FORCED TONITE WITH LIFTING OF THE WARM FRONT NORTH OF THE AREA...AND APPROACH OF THE UPPER TROF. DESPITE LACK OF IMPRESSIVE SURFACE BASED INSTABILITY...THERE ARE STILL A NUMBER OF FACTORS THAT COULD PRODUCE SEVERE WEATHER. CWFA IN LEFT EXIT REGION OF UPPER JET BY MORNING. GFS HAS A SUSPICIOUS CONVECTIVELY-INDUCED VORT LIFTING NORTH OF THE REGION TONITE...AND AN EVEN MORE SUSPICIOUS SPLIT OF THE UPPER JET THIS EVENING...WHICH CREATES A TREMENDOUS UPPER DIVERGENT BULLSEYE. AFOREMENTIONED SHEAR REMAINS DECENT THROUGH THE FIRST HALF OF THE OVERNIGHT. THERE IS ELEVATED INSTABILITY WITH STEEP LAPSE RATES IN THE INCREASINGLY DRY AIR ALOFT MOVING OVER THE NORTHERN HALF OF THE FORECAST AREA. AND WE EXPECT BROAD DIFFERNTIAL POSITIVE VORTICITY ADVECTION...ESPCEIALLY AFTER MIDNIGHT WHEN SHEAR PROFILES ARE NOT AS GOOD AS EARLIER. COULD ALSO SEE TORRENTIAL RAINFALL AS UPPER DIVERGENCE INCREASES LATE...AND IT SHOULD BE NOTED THAT BOTH ETA AND GFS KEEP A PERSISTENT 30 TO 45 KTS OF 85H FLOW INTO THE EASTERN FACING SLOPES OF THE APPALACHIANS OVERNIGHT. WE TENTATVIELY ARE ENCODING RAINFALL OF CLOSE TO TWO INCHES FOR THE ESCARPMENT LOCATIONS BUT WILL HOLD OFF ON FLOOD WATCH FOR NOW. THAT ALL BEING SAID...WE WENT WITH CATEGORICAL POPS TONITE AND EARLY MONDAY. UPPER LOW TO CROSS AREA MONDAY. BEST FORCING FOR PRECIPITATION LIFTS NORTH INTO SOUTHERN VIRGINIA DURING THE DAY BUT STEEP LAPSE RATES AND A WELL-MIXED BOUNDARY LAYER COULD RESULT IN GUSTY WINDS AND PERHAPS STRONG CONVECTION AGAIN FOR THE MOUNTAINS. WE KEPT LIKELY POPS FOR OUR NORTHERN TIER MONDAY...WITH CHANCE FOR UPSTATE/NORTHEAST GEORGIA. NOT MUCH ON THE HORIZON...FOR NOW ANWAY...MONDAY NITE THROUGH WEDNESDAY WITH HIGH PRESSURE IN CONTROL. LONG TERM (WEDNESDAY NIGHT THROUGH SUNDAY)... LATEST HPC MANUAL PROGS HAVE THE NEXT SIGNIFICANT COLD FRONT CROSSING THE REGION LATE FRIDAY AND EARLY SAT. THE HPC TIMING IS QUITE CLOSE TO THAT OF THE 1200 RUN OF THE GFS. THIS LOOKS TO BE ANOTHER STRONG TROF...AND UNLIKE WITH THE PAST COUPLE VIGOROUS SRN STREAM SHORT WAVES...THERE APPEARS TO BE LITTLE IF ANY INDICATION OF COLD AIR DAMMING AHEAD OF THE SYSTEM. THIS COULD CERTAINLY CHANGE... BUT IF THIS TREND CONTINUES...THEN THERE COULD BE A SEVERE THUNDERSTORM THREAT ACROSS MUCH OF THE REGION LATE FRI AND EARLY SAT. THE WEATHER FOR THE REST OF THE EXTENDED LOOKS BENIGN...AND GENERALLY FOLLOWED HPC/ENSEMBLE MEX MOS. AVIATION... PRIMARY CONCERN FOR TAFS THIS PACKAGE IS WHEN AND WHERE THE WEDGE WL ERODE. ATTM WNDS AT ALL TAFS SITES OUTSIDE THE MTNS ARE OUT OF THE ENE TO NE. THIS IS GENERALLY BETWEEN 45 AND 90 DEGREES OUT OF PHASE WITH THE NAM SURFACE WINDS WHICH WERE SOUTHEAST EVERYWHERE AT 18 UTC. THE FACT THAT THE SFC LOW WL BE DEEPENING TO OUR WEST...WHICH WL RESULT IN SOUTH TO SOUTHWEST LLVL WINDS...DOES NOT BODE WELL FOR THE HEART OF THE COLD POOL TO SCOUR IN THE IMMEDIATE LEE. THIS HAPPENS TO BE WHERE MOST OF THE TAFS SITES ARE...AND HAVE FOLLOWED MUCH CLOSER TO THE RUC WHICH THROUGH 0300 UTC HAS ONLY KCLT EVEN BEGINNING TO TURN MORE OUT OF THE SOUTH. CIGS SHOULD HOLD ON IN THE LIFR TO VLIFR RANGE AT MOST SITES...AND AS THE COLD DOME BECOMES SHALLOWER...VSBYS WL PROBABLY GET WORSE INTO THE EARLY EVENING HOURS. WE SHOULD RAPIDLY SCOUR LATE TNGT AS THE SFC LOW CROSSES THE REGION...AND HAVE MOST AREAS RAPIDLY IMPROVING 0600-0800 UTC. WILL TEMPO IN A 4 HR PERIOD OF THUNDER TRYING TO HIGHLIGHT THE PERIOD WHEN TSTMS WL BE MOST NUMEROUS. THIS SHOULD BE THE TIME FRAME ROUGHLY 4 HRS BEFORE A STRONG MCS CROSSES THE REGION BETWEEN ABOUT 0200 AND 0500 UTC TNGT. && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SHORT TERM...LANE sc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC 325 PM EST SUN MAR 27 2005 .SHORT TERM (TONIGHT THROUGH WEDNESDAY)... A SEVERE WEATHER WATCH BOX LOOMS OMINOUSLY TO THE WEST OF OUR CWFA...ONE COUNTY AWAY FROM OUR NORTHEAST GEORGIA WARNING UMBRELLA. KFFC 88-D HAS SHOWN A RAPID GROWTH OF CONVECTION THIS AFTERNOON AS MISSISSIPPI VALLEY SYSTEM BEGINS SHIFTING EASTWARD. THE GEORGIA CONVECTION IS LIFTING NORTHEAST RAPIDLY...AND FORWARD SPEEDS COULD CONTINUE TO INCREASE THIS EVENING AS UPPER FLOW AMPLIFIES. THERE HAS BEEN SOME LARGE HAIL UPSTREAM...UNDER THE MUCH STEEPER LAPSE RATES ASSOCIATED WITH BROAD SWATH OF DRIER MID LEVEL AIR. FARTHER SOUTHWEST...TORNADIC SUPERCELLS WERE DEVELOPING. DURING THE OVERNIGHT HOURS...DIRECTIONAL SHEAR PROFILES ON FORECAST SOUNDINGS AT THEIR BEST THROUGH 06Z...THEN ESPECIALLY THE LOW LEVEL FLOW PROGD TO VEER SIGNIFICANTLY SO THAT DIRECTIONAL SHEAR IS NOT AS GREAT. CWFA REMAINS STABLE AND WEDGED FOR THE MOST PART...ALTHOUGH STEADY RISES IN TEMPERATURE AND DEWPOINTS HAVE BEEN OBSERVED WITHIN THE DAMMING REGION...EVEN AS DRIZZLE AND PERIODS OF LIGHT RAIN HAVE AFFECTED THE NORTH. AS THE APPROACHING GEORGIA CONVECTION ENCOUNTERS THE COOLER AND STABLE AIR OVER OUR AREA...INITIAL WEAKENING WOULD BE EXPECTED. THE ARRIVAL OF THE BROAD CONVECTIVE AREA IN THE NEXT COUPLE OF HOURS WILL HASTEN THE DEMISE OF THE STABLE WEDGE OF AIR FOR NORTHEAST GEORGIA AND THE WESTERN UPSTATE. INTERIOR DAMMING REGION LOCATIONS...HOWEVER...AND ESPECIALLY THE NORTHERN FOOTHILLS AND NORTHWEST PIEDMONT...WILL LIKELY MAINTAIN THE WEDGE UNTIL SCOURING OCCURS LATE TONITE. EASTERN ZONES...AND THOSE SOUTHEAST ZONES BORDERING THE COLUMBIA FOREAST AREA OF RESPONSIBILITY...COULD ALSO SEE SIGNIFICANT EROSION OF THE STABLE COOL LAYER IN THE NEXT LITTLE WHILE. THE THERMAL MOISTURE BOUNDARY HAS WORKED WELL INTO THE MIDLANDS...WITH LOWER 60 DEWPOINTS NOT FAR TO OUR EAST OR SOUTH. THE WINDOW IS CLOSING...BUT THERE IS STILL TIME TO ERODE PART OF THE WEDGE FOR OUR SOUTHERN PIEDMONT OF NORTH CAROLINA AND THE EASTERN PIEDMONT OF SOUTH CAROLINA. IT WILL BE INTERESTING TO SEE WHAT TRANSPIRES TO OUR SURFACE FEATURES DURING THE NEXT TWO TO THREE HOURS. IF THE APPROACHING GEORGIA CONVECTION DOES NOT ERODE THE WEDGE...WHICH WE THOUGHT WAS POSSIBLE EARLIER BUT NOT SO CONFIDENT NOW...AND IF THE THERMAL MOISTURE BOUNDARY DOES NOT ERODE THE WEDGE ON OUR EASTERN AND SOUTHEAST PERIPHERY...THEN IT IS LIKELY THAT THE WEDGE WILL HOLD UNTIL EROSION IS FORCED TONITE WITH LIFTING OF THE WARM FRONT NORTH OF THE AREA...AND APPROACH OF THE UPPER TROF. DESPITE LACK OF IMPRESSIVE SURFACE BASED INSTABILITY...THERE ARE STILL A NUMBER OF FACTORS THAT COULD PRODUCE SEVERE WEATHER. CWFA IN LEFT EXIT REGION OF UPPER JET BY MORNING. GFS HAS A SUSPICIOUS CONVECTIVELY-INDUCED VORT LIFTING NORTH OF THE REGION TONITE...AND AN EVEN MORE SUSPICIOUS SPLIT OF THE UPPER JET THIS EVENING...WHICH CREATES A TREMENDOUS UPPER DIVERGENT BULLSEYE. AFOREMENTIONED SHEAR REMAINS DECENT THROUGH THE FIRST HALF OF THE OVERNIGHT. THERE IS ELEVATED INSTABILITY WITH STEEP LAPSE RATES IN THE INCREASINGLY DRY AIR ALOFT MOVING OVER THE NORTHERN HALF OF THE FORECAST AREA. AND WE EXPECT BROAD DIFFERNTIAL POSITIVE VORTICITY ADVECTION...ESPCEIALLY AFTER MIDNIGHT WHEN SHEAR PROFILES ARE NOT AS GOOD AS EARLIER. COULD ALSO SEE TORRENTIAL RAINFALL AS UPPER DIVERGENCE INCREASES LATE...AND IT SHOULD BE NOTED THAT BOTH ETA AND GFS KEEP A PERSISTENT 30 TO 45 KTS OF 85H FLOW INTO THE EASTERN FACING SLOPES OF THE APPALACHIANS OVERNIGHT. WE TENTATVIELY ARE ENCODING RAINFALL OF CLOSE TO TWO INCHES FOR THE ESCARPMENT LOCATIONS BUT WILL HOLD OFF ON FLOOD WATCH FOR NOW. THAT ALL BEING SAID...WE WENT WITH CATEGORICAL POPS TONITE AND EARLY MONDAY. UPPER LOW TO CROSS AREA MONDAY. BEST FORCING FOR PRECIPITATION LIFTS NORTH INTO SOUTHERN VIRGINIA DURING THE DAY BUT STEEP LAPSE RATES AND A WELL-MIXED BOUNDARY LAYER COULD RESULT IN GUSTY WINDS AND PERHAPS STRONG CONVECTION AGAIN FOR THE MOUNTAINS. WE KEPT LIKELY POPS FOR OUR NORTHERN TIER MONDAY...WITH CHANCE FOR UPSTATE/NORTHEAST GEORGIA. NOT MUCH ON THE HORIZON...FOR NOW ANWAY...MONDAY NITE THROUGH WEDNESDAY WITH HIGH PRESSURE IN CONTROL. && .LONG TERM (WEDNESDAY NIGHT THROUGH SUNDAY)... LATEST HPC MANUAL PROGS HAVE THE NEXT SIGNIFICANT COLD FRONT CROSSING THE REGION LATE FRIDAY AND EARLY SAT. THE HPC TIMING IS QUITE CLOSE TO THAT OF THE 1200 RUN OF THE GFS. THIS LOOKS TO BE ANOTHER STRONG TROF...AND UNLIKE WITH THE PAST COUPLE VIGOROUS SRN STREAM SHORT WAVES...THERE APPEARS TO BE LITTLE IF ANY INDICATION OF COLD AIR DAMMING AHEAD OF THE SYSTEM. THIS COULD CERTAINLY CHANGE... BUT IF THIS TREND CONTINUES...THEN THERE COULD BE A SEVERE THUNDERSTORM THREAT ACROSS MUCH OF THE REGION LATE FRI AND EARLY SAT. THE WEATHER FOR THE REST OF THE EXTENDED LOOKS BENIGN...AND GENERALLY FOLLOWED HPC/ENSEMBLE MEX MOS. && .AVIATION... PRIMARY CONCERN FOR TAFS THIS PACKAGE IS WHEN AND WHERE THE WEDGE WL ERODE. ATTM WNDS AT ALL TAFS SITES OUTSIDE THE MTNS ARE OUT OF THE ENE TO NE. THIS IS GENERALLY BETWEEN 45 AND 90 DEGREES OUT OF PHASE WITH THE NAM SURFACE WINDS WHICH WERE SOUTHEAST EVERYWHERE AT 18 UTC. THE FACT THAT THE SFC LOW WL BE DEEPENING TO OUR WEST...WHICH WL RESULT IN SOUTH TO SOUTHWEST LLVL WINDS...DOES NOT BODE WELL FOR THE HEART OF THE COLD POOL TO SCOUR IN THE IMMEDIATE LEE. THIS HAPPENS TO BE WHERE MOST OF THE TAFS SITES ARE...AND HAVE FOLLOWED MUCH CLOSER TO THE RUC WHICH THROUGH 0300 UTC HAS ONLY KCLT EVEN BEGINNING TO TURN MORE OUT OF THE SOUTH. CIGS SHOULD HOLD ON IN THE LIFR TO VLIFR RANGE AT MOST SITES...AND AS THE COLD DOME BECOMES SHALLOWER...VSBYS WL PROBABLY GET WORSE INTO THE EARLY EVENING HOURS. WE SHOULD RAPIDLY SCOUR LATE TNGT AS THE SFC LOW CROSSES THE REGION...AND HAVE MOST AREAS RAPIDLY IMPROVING 0600-0800 UTC. WILL TEMPO IN A 4 HR PERIOD OF THUNDER TRYING TO HIGHLIGHT THE PERIOD WHEN TSTMS WL BE MOST NUMEROUS. THIS SHOULD BE THE TIME FRAME ROUGHLY 4 HRS BEFORE A STRONG MCS CROSSES THE REGION BETWEEN ABOUT 0200 AND 0500 UTC TNGT. && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SHORT TERM...SAB LONG TERM...BPM AVIATION...BPM sc