SOUTH CENTRAL AND SOUTHEAST COLORADO AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE PUEBLO 856 PM MST WED MAR 22 2000 A QUICK UPDATE ON THE WEATHER. IN BETWEEN TWO SYSTEM...AT THE MOMENT. CURRENT WATER VAPOR/IR SATELLITE IMAGERY ANIMATION SHOWED MID-LEVEL SHORTWAVE TROUGH ROTATING THROUGH THE SOUTHWEST MOUNTAINS WITH PLENTY OF LIGHTNING ACTIVITY. HAVE ONLY HAD 1" REPORT AROUND CREEDE. THIS TROUGH IS ROTATING THROUGH THE LARGER PARENT LOW MIGRATING INTO SOUTHWESTERN NM. ASSOCIATED LARGE SCALE ASCENT STILL IN CENTRAL 1/3 OF NM AND PRECIPITATION ROTATING NORTHWESTWARD INTO NORTHWESTERN NM AND EXTREME SOUTHWESTERN CO. SECOND SYSTEM, A "WEDGE" MCS AT THE EXIT REGION OF THE LLJ HAS REMAINED NEARLY STATIONARY ACROSS THE TX PANHANDLE/ CENTRAL TX. AS YOU USUALLY SEE WITH THESE SYSTEMS...THE MOISTURE INFLUX IS BEING IMPEDED FROM ANY FURTHER MIGRATION NORTHWARD AND WESTWARD. SUBSEQUENTLY...THIS IS WHY THERE HAS BEEN VERY LITTLE IN THE WAY OF PRECIPITATION ACROSS MUCH OF THE CWFA, EXCEPT FOR SCATTERED -SHSN AND -TSSN IN SOUTHWEST CO MOUNTAINS. NEWEST RUC/ETA...CONTINUE TO TREND UPPER LOW SHIFTING INTO SOUTHEASTERN NM BY THU MORNING WITH MCS EXPECTED ACROSS MUCH OF WESTERN TX/OK PANHANDLE/WESTERN KS. DEFORMATION CLOUD AND PRECIPITATION SHIELD SHOULD BECOME MORE DEFINED FROM CENTRAL NM INTO SOUTHEASTERN CO AND WESTERN KS BY EARLY THU MORNING. NEWEST ETA CONTINUES TO TREND CLOSED LOW BECOMING AN "OPEN WAVE" AS IT MOVES INTO CENTRAL KS BY THU AFTERNOON. SYSTEM'S TEMPERATURES ARE STILL EXPECTED TO WARM...SO THE THREAT OF ANY SNOW IN THE PLAINS IS VERY LOW GIVEN LATEST 850-700MB THICKNESS VALUES, UNLESS THE DIABATIC COOLING FROM INTENSE LARGE SCALE ASCENT FORCES IT OVER THE SNOW. REALLY DO SEE THIS YET. STILL COULDN'T RULE OUT SOME SCATTERED -SHSN IN THE MOUNTAINS. PLAN TO KEEP THE HIGHEST POPS OUT TOWARDS THE CO/KS BORDER AND DIMINISH WESTWARD FOR THE REMAINDER OF THE NIGHT. THE I-25 CORRIDOR WILL BE A TOUGH CALL. CURRENT "LIKELIES" FOR 73/74/75/76 TONIGHT SEEMS TOO HIGH GIVEN LATEST SATELLITE/RADAR/NEW MODEL RUNS. WILL TRIM BACK TO 50% AND MENTION LATE TONIGHT. GIVEN A VERY SATURATED SURFACE/BOUNDARY LAYER FROM PAST RAINFALL...THERE SHOULD BE A FOG THREAT IN THE PLAINS. GENTLE SOUTHERLY (PALMER DIVIDE UPSLOPE) FLOW ALREADY RESPONSIBLE FOR COS DOWN TO 1/2SM-3/4SM. NWS SPOTTERS REPORTING FOGGY CONDITIONS ACROSS NORTHERN EL PASO COUNTY. COS HIGHWAY WEBCAMS NOT SHOWING FOG THAT WIDESPREAD. NOTHING FORMING YET IN THE AR RIVER VALLEY...THOUGH. ANY HEAVIER RAINFALL WILL KNOCK THE FOG OUT LATER ON TONIGHT. WILL MENTION ONLY IN THE COS AREA...FOR NOW. .PUB...NONE. METZE co NORTHEAST AND NORTH CENTRAL COLORADO AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DENVER COLORADO 200 PM MST WED MAR 22 2000 SHORT TERM DISCUSSION...RADAR LOOPS THIS AFTN SHW A LRG MASS OF PCPN CONTG TO MOVE NWD TWD AREA FM SERN CO BUT MST OF THIS PCPN IS DISIPATING AS IT MOVES OVR PALMER DVD. HWVR SUM SNW SHWRS HAVE MOVED INTO PARK AND SUMMIT COUNTIES. MDLS CONT TO SKIRT MST OF THIS PCPN TO S AND E OF METRO DEN TNGT AND WILL GO ALG WITH THIS IDEA. WILL GENLY FVR MESOETA SOLUTION ATTM WHICH SHWS A BRIEF SHOT OF PCPN OVR METRO DEN THIS EVE AND GREATER AMTS FRTHR E THRU THE NGT. MDLS ALSO KEEP MST OF PCPN OVR PLAINS IN FORM OF RAIN TNGT WITH ONLY THAT AMT NR ERN FTHLLS AS SNW. CANNOT ARGUE TOO MUCH WITH THIS BUT WITH LO TEMPS IN LWR 30S MUST MENTION RAIN CHNGG TO SNW LATE. GARD...WFO BOULDER LONG TERM DISCUSSION: UPR LVL LOW OVER XTRM SERN AZ IS SLOWLY BEGINNING TO LIFT OUT AS FCST BY YSTDY'S MDLS WITH THE APCH OF A BROAD TROF TWD THE W COAST AS WELL AS ANOTHER WAVE IN THE SUBTROPICAL JET STREAM WEST OF BAJA. MRNG UPR LVL PLOTS AND LATEST RUC SHOWS STRONGEST 300 MB JET MOVING AROUND TO THE BASE OF THE UPR LOW THIS AFTN. DECENT UPR LVL FORCING EAST OF THE SYSTEM WITH AN UPR LVL JET MOVING INTO ERN CO BUT DESPITE INCRSG UPSLOPE ON PROFILER PCPN RMNS S OF FCST AREA ATTM. UNFORTUNATELY THE UPR LOW SHIFTS TO THE EAST BEFORE BGNG ITS NE MOTION AFTER 00Z AND THIS RESULTS IN A TRACK THAT WILL TAKE THE UPR LO JUST A BIT TOO FAR E TO BRING ANY SUBSTANTIAL PCPN TO MOST OF OUR FCST AREA. MODELS ARE ALL IN REMARKABLE AGREEMENT WITH THE TRACK OF THE UPR LO...THO DIFFER A BIT IN THE AMNT OF PCPN THAT GETS WRAPPED ARND SYSTEM INTO ERN CO. ETA MIGHT BE CUTTING MSTR OFF A BIT TOO SHARPLY BASED ON HOW IT IS HANDLING CRNT 700 MB FLOW IN SERN CO BUT WUD TAKE A SUBSTANTIAL SHIFT IN THE FCST FOR ANY SIG PCPN NEAR THE FRONT RANGE. PROB ENUF UNCERTAINTY...WRAPARND MSTR AND UPSLOPE FLOW TO HAVE POPS ABT AS PER CRNT FCST FOR THU EXCEPT WILL NEED TO UP THE POPS FAR ERN ZONES LIKE 48..49 AND 50 WCH ARE CLOSE TO SOME VERY SUBSTATIAL PCPN THAT WILL HIT WRN KS. NOT SURE ABOUT THE CLEARING FOR THU AS EARLY AS INDC IN THE CRNT FCST...IT CUD HAPPEN BUT THE ETA WUD HAVE TO EXACTLY VERIFY OVER ANY OTHER MODEL AND APRS TO BE A TAD FAST. THE UPR LO WILL CARRY COLD AIR WITH IT BUT BECAUSE IT TRACKS OVER N TX AND SW KS IT SHD RMN TOO WARM FOR ANY SNOW WHERE THE MOST PCPN WUD FALL FARTHER TO THE E IN NERN CO. MIXED BAG IN AREAS WHERE THERE IS A CHC OF LGTER PCPN BUT AGAIN POPS WILL BE LESS THAN 50 PCNT. FOR THE MTNS DON'T SEE MUCH AS MOST PCPN SHD RMN TO THE SE OF EVERYTHING XCPT MAYBE INTO ZN 36..37 AND PERHAPS PARTS OF 34. CLRG THU NGT BUT WK TROF ACRS AREA ON FRI SO CHC OF MTN SNOW SHWRS. CUD BE A SURGE FM THE N INTO NERN CO LWR ELEVATIONS BUT NGM SEEMS SMWHT OVERDONE WITH THIS VS OTHER MDLS AND WILL KEEP IT DRY FOR NOW. LONGER TERM SATURDAY STILL LUKG WARMER AND DRY AHEAD OF THE NEXT UPR LOW. THE HI PRES TO OUR N CUD SNEAK DOWN ONTO THE PLAINS SAT IF IT DOESN'T ON FRI AND BRING A BIT COOLER TEMPS BUT FOR NOW WILL STICK WITH THE WARMER FCST CRNTLY IN THE EXTENDED AS PER AVN MODEL SLTN. MDLS IN GNL AGREEMENT WITH THE TIMING OF THE NEXT SYSTEM...MOVING AN UPR LO INTO NM BY LATE MONDAY. SFC HI NOT IN PLACE FOR BRINGING ANY COLD AIR TO LOWER LEVELS SO WUD DEPEND ON TRACK OF UPR LO FOR AMNT OF PCPN AND TYPE...PROB MOSTLY RAIN AT LOWER ELEVATIONS EAST OF THE FRONT RANGE...BUT OF COURSE MUCH CUD CHANGE BY MONDAY. SZOKE .DEN...NONE. co NORTHEAST AND NORTH CENTRAL COLORADO AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DENVER COLORADO 4 AM MST WED MAR 22 2000 ...UPDATE TO SHORT TERM DISCUSSION... HAVE CHANGED MIND ABOUT MOSTLY SUNNY FOR THIS MRNG. WILL GO WITH INCREASING CLOUDS SINCE LEAD EDGE OF HIGH CLOUDS ALREADY OVER CWA ACCORDING TO SAT LOOP AND APPEAR THICKER THAN EXPECTED. PRESENCE OF RDG OVER CWA SHUD KEEP AMS MSTLY STBL SO RIDING WITH LOW POPS. SHORT TERM DISCUSSION...UPPER LOW IN AZ NOT EXPECTED TO MAKE MUCH MOVEMENT TODAY. MODELS INCLUDING 06Z RUC SHOW LOW INVOF TRI-POINT AREA OF AZ/NM/MEXICO BRDRS AT 18Z EXCEPT ETA WHICH IS 6 HRS SLOWER AND PUTS LOW THERE AROUND 06Z TNGT. THIS WILL KEEP DFLNT SLY FLOW OVER NERN CO TODAY. E-W ORIENTED RDG OVER THE AREA TO PRETTY MUCH SQUASH ANY PCPN THREAT UNTIL LATE AFTN WHEN THE RDG REACHES CO-WY BRDR AND START TO GET A LITTLE MORE INSTBY AND MSTR. WILL CUT THE POPS BACK TO ISOLD FOR PLAINS ZONES AS NO MECHANISM TO PROVIDE ANY LIFT UNTIL LATE AFTN. MAY GET SOME ORGRPHC LIFT OMTNS THUS WIDELY SCT SEEMS APPROPRIATE FOR ZONES 34...37...36 LATE TODAY WITH ISOLD REST OF MTN AND FTHL ZONES. WILL ALSO ADJUST MANY ZONES TO MOSTLY SUNNY FOR THIS MRNG WITH INCRSG CLDS IN AFTN. SOME HI LVL CLDS IN THE SRN PTN CWA ALREADY BUT SHUD BE THIN ENUF FOR PLENTY OF SUN TO SHINE THRU TIL MIDDAY WHEN THICKER SHIELD EXPECTED TO ARRIVE. SAT FOG PRODUCT SHOW LOW CLDS ARE BEING SWEPT E AND N AND NOW CONFINED TO LOGAN...SEDGWICK...PHILLIPS AND NE WASHINGTON COUNTIES AND MNLY MOVING NEWD WITH DRAINAGE WIND AUGMENTING WEAK S-SW FLOW. ANOTHER BAND OF LOW CLOUDS SIGHTED IN ERN LARIMER AND WELD COUNTY BUT THEY DO APPEAR TO BE MOVING N. WILL WAIT AND SEE WHAT SAT PIX SHOWS AT PRESS TIME BEFORE COMMITTING TO MRNG LOW CLDS IN ZONES. PRESENTLY LEANING TO MENTN ONLY IN ZONES 42-44...48 AND 50. LOW CLOUDS SHUD DISSIPATE BY 9 OR 10 AM. WITH SLY FLOW...FAIR AMT OF SUN AND SOME WAA EXPECT TEMPS TO CLIMB WELL ABOVE YESTERDAYS HIGHS WHICH AGREES WITH NUMERICAL GDNC. PREFER WARMER FAN OVER FWC FOR TODAYS TEMPS. BOODA LONG TERM DISCUSSION: MDLS RMN SIMILAR IN FCST TRACK OF THIS SLOW MOVING CLOSED LOW...MOVING IT INTO THE OKLAHOMA PANHANDLE BY 00Z FRI. NERN CO IS STUCK IN MORE OF A DEFORMATION AREA AS THIS STORM SYSTEM RMNS S AND E OF THE CWA. ETA TRIES TO DRY THE AMS OUT AFT 12Z THU WITH THE FCST SNDG VEERING WINDS ARND TO THE W. THE NGM AND AVN MAINTAIN A DEEP MSTR OVER CO TNGT AND MOST OF THU AS WNDS RMN ESELY THRU THE PD. BST POTENTIAL FOR SHOWERS WL RMN OVR SRN AND ERN PORTIONS OF THE CWA TGNT AND THU. ONLY FVBL FACTORS FOR SHOWERS WOULD APPEAR TO BE THE WEAK ESELY UPSLOPE THE MDLS GENERATE AND THE DEFORMATION ZONE THAT STICK OVR NERN CO. ON THE FLIP SIDE...THE QG FORCING APPEARS MINIMAL AND MID LVL INSTBY OVR NERN CO IS FAIRLY WEAK. SO FAR...THE MDLS HAVE CONSISTENTLY OVERDONE THE QPF FOR OUR CWA AND ARE PROBABLY DOING SO ATTM. AVN FINALLY SWINGS WNDS ARND TO THE NW FRI EVNG AS SYSTEM MOVES FURTHER E SO SHUD SEE SOME PARTIAL CLRG BY FRI AFTN...AT LEAST ACRS WRN SECTIONS OF THE CWA. AVN WEAKENS THE NEXT SYSTEM OFF THE PACIFIC NW COAST AS IT MAKES ITS WAY INLAND. AS A RESULT...BST CHC FOR ANY PCPN WITH THIS STORM FRI WL BE CONFINED TO THE MTNS. NEXT TROF SET TO DROP INTO THE GREAT BASIN AND CLOSE OFF SUNDAY INTO MON. SEE NO REASON TO MAKE ANY CHANGES TO THE EXTENDED ATTM. COOPER .DEN...NONE. co AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE KEY WEST FL 930 PM EST WED MAR 22 2000 CURRENTLY... IR SATELLITE LOOPS...METARS...AND C-MAN SITES AT LAKE WORTH AND GRAND BAHAMA ISLAND VERIFY THAT THE BACK-D00R SURGE IS CLOSE TO EXPECTED SCHEDULE. AT 9 PM THIS FEATURE EXTENDED WEST OVER THE BAHAMAS NORTHWEST PROVIDENCE CHANNEL TO THE FLORIDA COAST AT THE PALM BEACH-BROWARD LINE. WIND AT THIS FEATURE GOES NNE 15 KT GUSTING TO 20 KT ACCORDING TO C-MAN SITES. INTERESTINGLY...OTHER NARROW CUMULUS LINES PARALLEL TO THIS SURGE FEATURE...BUT AHEAD OF IT ...HAVE APPEARED. ONE SUCH LINE IS MOVING SOUTH ALMOST AT THE NORTH TIP OF KEY LARGO OVER TO ANDROS ISLAND. WIND GOES NNE WITH THESE MINOR CLOUD LINES...BUT THE SPEEDS AT 10 KT OR LESS IT SEEMS. MEANWHILE...A SURFACE TROUGH IS SEEN IN THE PRESSURE ANALYSIS RUNNING ALONG THE WEST SIDE OF THE FLORIDA PENINSULA JUST INLAND FROM CAPE SABLE TO INLAND FROM SARASOTA. AS A RESULT...WINDS OVER THE GULF COASTAL WATERS AND THE LOWER AND MIDDLE KEYS HAVE BEEN STEADY NW...SPEEDS 10 KT IN THE GULF AND 5-10 KT CLOSER TO THE KEYS. UPPER KEYS HAVE ALMOST NO WIND AS OF 9 PM. 00Z SOUNDING AT KEY WEST SHOWS INVERSION A BIT LOWER THAN LAST NIGHT...NOW AROUND 5 THSD FT. WINDS JUST BELOW THE INVERSION ARE FROM THE NORTH. AS A RESULT... SIMILAR TO LAST NIGHT..BROKEN TO OVER STRATOCUMULUS HAS FORMED FROM SPREADING OUT OF AFTERNOON CUMULUS OVER THE MAINLAND...AND ADVECTED SOUTH OVER THE UPPER AND MIDDLE KEYS. ALSO WHAT APPEARS TO BE SOME LOWER CUMULUS IS SEEN ON SATELLITE HAVING FORMED IN THE GULF WATERS JUST NORTH OF THE LOWER KEYS. FIRST PERIOD FORECASTS... THE 18Z RUC HAS BEEN VERIFYING FAIRLY WELL THE PAST FEW HOURS WITH REGARD TO SURFACE WINDS OVER THE REGION...AND WITH REGARD TO THE 850 MB MOISTURE PATTERN (STRATOCUMULUS LAYER). 1030 PM COASTAL MARINE FORECASTS ONLY DID A MINOR TWEAK OF WINDS...TO CONFORM WITH CURRENT TRENDS DISCUSSED ABOVE AND THE TRANSITION INTO THE FORECAST FOR LATE TONIGHT. EXTRAPOLATION OF THE SURGE FEATURE PUTS IN INTO THE UPPER KEYS BY 06Z OR SOON AFTER TONIGHT...AND OVER REST OF AREA BY 12Z THU. RUC STILL SHOWS WINDS GOING NE 15 KT OR SO WITH THIS FEATURE. PUBLIC ZONES WERE UPDATED A LITTLE WHILE AGO TO ACCOUNT FOR THE CLOUD TRENDS. THE RUC SQUEEZES OUT SOME LIGHT QPF OVER THE UPPER KEYS AFTER 06Z TONIGHT...BUT I DECIDED NOT TO INCLUDE MENTION OF POPS WITH THE CLOUD UPDATE. COASTAL MARINE FORECAST ALREADY ADDRESSES THE POSSIBILITY OF ISOLATED SHOWERS TONIGH WITH THE SURGE-RELATED MOISTURE. .EYW...NONE. CLB fl AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TALLAHASSEE FL 841 PM EST WED MAR 22 2000 MODELS/ZFP: TIGHTENING GRADIENT ASSOCIATED WITH THE BACK DOOR FRONT EVIDENT INTO SC THIS EVENING AND MAKING STEADY PROGRESS SE. THIS GRADIENT SHOULD PREVENT ANY FOG FROM FORMING IN THE CWFA. 18Z ETA AND LATEST RUC INDICATE ANY LOW CLOUDS ASSOCIATED WITH THE WEDGE WILL NOT MAKE IT THIS FAR SE UNTIL DAYLIGHT. MID/HIGH CLOUDS HAVE DISSIPATED AS WELL SO WILL JUST GO CLEAR TONIGHT. 01Z TEMPS RUNNING A BIT ABOVE GUIDANCE IN FL AND A BIT BELOW IN GA. ALL IN ALL...MIN TEMP FORECAST LOOKS REASONABLE. THE AFOREMENTIONED MODELS INDICATE THAT OUR TEMP AND SKY COVER FORECAST FOR THU MAY BE A BIT TOO OPTIMISTIC. I/LL HOLD OFF MODIFYING SECOND PERIOD AT THIS TIME AND LET MID SHIFT TAKE A LOOK AT THE 00Z SUITE. MARINE: LOOKS AS IF NE SURGE BEHIND BACK DOOR FRONT WILL HOLD OFF UNTIL THE PREDAWN HOURS. THIS IS PRETTY MUCH COVERED IN CURRENT CWF. .TLH... AL...NONE. GA...NONE. FL...FIRE WEATHER WATCH THU AFTN ALL INLAND ZONES. WOOL fl WEST CENTRAL AND SOUTHWEST FLORIDA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TAMPA BAY AREA - RUSKIN FL 825 PM EST WED MAR 22 2000 CURRENTLY...SCATTERED MID AND HIGH LEVEL CLOUDS ASSOCIATED WITH WEAK 50H DISTURBANCE MOVING SEWD IN ANTICYCLONIC NWLY FLOW ALOFT AND SURFACE BACK-DOOR TYPE BOUNDARY IS ADVANCING SEWD FROM THE BIG BEND REGION EARLY TONIGHT...WHICH IS DEPICTED WELL BY ETA/NGM MODEL TIME- HEIGHTS. AS THE NIGHT CONTINUES SHOULD SEE MOST OF THESE MID/HIGH CLOUDS THIN OUT OR ERODE AS LARGE SCALE SUBSIDENCE INCREASES... HOWEVER THE RUC AND MESO-ETA DEPICTS INCREASING 1000-850MB LAYERED MOISTURE ADVECTING WESTWARD IN INCREASING NELY BL FLOW OVERNIGHT SO PLAN TO REWORD FOR PARTLY CLOUDY SKIES LATE TONIGHT IN AN UPDATE LATER THIS EVENING. INCREASING NELY BOUNDARY LAYER FLOW SHOULD RESULT IN ADEQUATE MIXING AND KEEP ENOUGH OF A BREEZE GOING OVERNIGHT TO HOLD OFF FOG IN MOST LOCATIONS AND TO KEEP TEMPS CLOSE TO FORECASTED MINS DESPITE WEAK SHALLOW CAA...THUS NO OTHER CHANGES ARE PLANNED. MARINE...C-MAN AND OFFSHORE BUOYS STILL INDICATING LIGHT WINDS AND RELATIVELY FLAT SEA STATES AT THE MOMENT...BUT AS THE NIGHT CONTINUES STILL LOOKING FOR AN INCREASE IN WIND AND SEA STATES AS GRADIENT TIGHTENS...SO WILL LEAVE SCEC IN PLACE WITH NO CHANGES PLANNED IN 1030 PM UPDATE. .TBW...SCEC BONITA BEACH TO SUWANNEE RIVER INCLUDING THE TAMPA BAY WATERS TONIGHT. FIRE WEATHER WATCH ALL COUNTIES THURSDAY AFTERNOON. MCMICHAEL fl EAST CENTRAL FLORIDA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MELBOURNE FL 1000 AM WED MAR 22 2000 E-W BAND OF LOW CLOUDS CONTINUES TO MOVE DOWN THE PENINSULA AND SHRINK. SATELLITE TREND REVEALS BAND WILL AFFECT SOUTHERNMOST COUNTIES NEXT HOUR OR SO...FOLLOWED BY RAPIDLY IMPROVING SKY CONDITIONS. BUOYS N OF CWA INDICATE PASSAGE OF NE WIND SURGE OVER LAST FEW HOURS. 13Z RUC SHOWS ONSET OF GUSTY NE FLOW SPREADING N-S ACROSS CWA THIS AFTERNOON AND EARLY EVENING...THEN PERSISTING FOR SOME TIME AS TIGHT GRADIENT TAKES HOLD. WILL UPDATE ZFP SHORTLY TO REMOVE EARLY MORNING LOW CLOUDS AND FOG CENTRAL AND SOUTH. ONSHORE FLOW AND SHALLOW MOISTURE SHOULD PROMOTE PARTLY CLOUDY SKIES TODAY. FIRE WX...WILL MAINTAIN INTERIOR FIRE WX WATCH FOR THE TIME BEING..BUT EXPECT TO CANCEL AT LEAST A PORTION OF THE WATCH WITHIN NOON SMF PRODUCT. ALTHOUGH 12Z TBW SOUNDINGS STILL DRY...XMR SOUNDING SHOWS LOW LEVELS MOISTENING..AND WITH DEVELOPMENT OF INCREASING NE FLOW THIS AFTERNOON...GREATEST THREAT FOR MARGINAL WARNING THRESHOLD WILL BE NORTHERN INTERIOR COUNTIES. MARINE...FORECAST WILL REMAIN UNCHANGED...HOWEVER WILL HEADLINE SCEC FOR NORTHERN LEG THIS AFTERNOON FOR INCREASING WIND/SEAS. SCA LIKELY ON NEXT PACKAGE AS WIND/SEAS CONTINUE TO BUILD. RIP CURRENT THREAT WILL REMAIN GREATER THAN NORMAL THIS AFTERNOON DUE TO RESIDUAL LONG PERIOD SWELL AND ONSHORE FLOW TRAJECTORY. .MLB...FIRE WEATHER WATCH THIS AFTERNOON FOR ORANGE/LAKE/SEMINOLE/ OSCEOLA AND INTERIOR VOLUSIA COUNTIES. AVIATION/FIRE WX...BRAGAW PUBLIC/MARINE......SPRATT fl AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE QUAD CITIES IA IL 255 PM CST WED MAR 22 2000 LATEST SFC AND MSAS ANALYSIS INDICATING DIRTY SFC HIGH CENTERED OVER NORTHERN IL...STILL INFLUENCING REGION/S WX WITH LOW-LEVEL MOISTURE /STRATOCU DECK TRAPPED UNDER H9-H85 INVERSION. VIS LOOP DOES SHOW BREAKS BUILDING ACRS SOUTHWEST HALF OF CWA...ALTHOUGH HIGHER LEVEL STRATOCU DECK STREAMING IN FROM SOUTHWEST ALONG RUC H7-H3 MB THICKNESS FIELDS ACRS SOUTHEAST NE AND SOUTHWEST IA. AT LEAST TODAY A LITTLE MORE IN THE WAY OF SFC FLOW AND THUS BETTER VISIBILITIES...ALTHOUGH WEAK AT BEST. FCST CONCERNS CONTINUE TO BE SKY COVER...POSSIBLE FOG...AND EVENTUAL PRECIP CHANCES LATER IN FCST. IN SHORTER TERM FOR TONIGHT...FEEL MOSTLY CLOUDY/CLOUDY CONDITIONS WILL CONTINUE TO PREVAIL...ALTHOUGH BREAKS WILL BE POSSIBLE FROM TIME TO TIME...ESPECIALLY ACRS THE SOUTH. MODELS AGAIN HANDLING LOW LEVEL RH FIELDS RATHER POORLY...BUT WILL TRY AND GET GENERAL CONSENSUS. ETA AND NGM H85-H5 LMRH/S INCREASE OVERNIGHT...PROBABLY DUE TO MID LEVEL CLOUDS ADVECTING IN FROM CENTRAL PLAINS. MODELS ACTUALLY PROG H85 RH/S TO DRY OUT OVER THE SOUTH HALF OF THE CWA OVERNIGHT BEFORE INCREASING AGAIN ON THU...BUT BOUNDARY LAYER AND H925 RHS KEEP AT 70+ VALUES OVER MOST OF CWA OVERNIGHT. FCST SOUNDINGS DO SHOW WEAKENING INVERSION TONIGHT...BUT QUICKLY GETS REINFORCED DURING DAY ON THU AS H8- H7 FLOW VEERS TO SOUTHWEST AND INCREASES...WITH LOW LEVEL MOISTURE ONCE AGAIN TRAPPED. AT THIS POINT...HARD TO BELIEVE ANY RH PROG BUT FEEL MOSTLY CLOUDY WORDING FOR TONIGHT AND THU THE WAY TO GO...ALTHOUGH PERIODS WITH BREAKS IN DECK DEFINITELY POSSIBLE. ALSO WATCHING SCTRD SPRINKLES ACRS NORTH-CENTRAL MO MOVING NORTHEAST...BUT NOT SURE THEY WILL HOLD TOGETHER TO AFFECT SOUTHERN CWA. WILL WATCH TREND TOWARD ISSUANCE TIME. WILL LEAN TOWARD WARMER FWC FOR LOWS TONIGHT. FEEL FOG WILL BE LIGHT ENOUGH TONIGHT NOT TO MENTION IN ZONES/MUCH LIKE LAST NIGHT/ WITH CONTINUING LIGHT SFC FLOW AND CLOUD COVER...ALTHOUGH IF MORE BREAKS DVLP AND PERSIST...SOME PATCHY DENSE POSSIBLE. SHORT RANGE MODELS HAVE GOOD AGREEMENT IN LIFTING WELL ADVERTISED SOUTHWEST CUT-OFF LOW OUT OF GRT BASIN AFTER 12Z THU AS 100+ KT H3 JET MAX ROUNDS IT/S BASE...AND UPSTREAM KICKER BOOTS IT/S WAY INTO THE SOUTHWEST. UPPER SYSTEM LOOKING TO WEAKEN AS IT LIFTS UP AGAINST SHARP UPPER RIDGE AND SHOULD REACH A SOUTHEAST NE POSITION BY 12Z FRI. WEAK VORT PIECES LOOK TO SHEAR OUT ACRS IA ON THU OUT OF MAIN VORTEX WITH LITTLE IMPACT. MAIN VORT THAN PROGGED TO PROGRESS TO NORTHEAST KS BY 12Z FRI. AS SYSTEM PULLS UP...FEEL ETA TOO AGGRESSIVE SPILLING PRECIP NORTHEAST ACRS WESTERN CWA AFTER 06Z FRI...WHILE AVN AND NGM KEEP PRECIP WEST OF CWA THROUGH 48 HRS. DVLPNG DRY EAST-SOUTHEAST SFC FLOW THU NIGHT MIGHT HOLD PRECIP AT BAY FOR AWHILE TO THE WEST AND SOUTH... PRECIP MIGHT FOCUS MORE UNDER UPPER LOW AND ALONG SFC WARM FRNT SETTING UP OVER MO...ALTHOUGH THIS FEATURE NOT VERY WELL DEFINED AND LOOKING TO EVENTUALLY OCCLUDE. LOW LEVEL THTA-E ADVECTION TO INCREASE ACRS EAST IA AFTER 06Z FRI ON NOSE OF DVLPING SOUTHERLY H85 FLOW...AS WELL AS LOW LEVEL CONVERGENCE. MAY CONTINUE LOW POPS FOR JUST SHOWERS ACRS SOUTHWEST 2/3'S OF CWA LATE THU NIGHT AS INSTABILITY LACKING AND BEST UPPER DIFFLUENCE FROM LEFT EXIT REGION LOOKS TO SET UP OVER SOUTH HALF OF MO. POSITIVE OMEGAS DO INCREASE TOWARD 12Z FRI AND AFTER...AND WITH UPPER SYSTEM ROTATING ACRS CENTRAL AND EASTERN IA ON FRI AND IT/S ASSOCIATED COOLER POOL OF AIR ALOFT...MID LEVEL INSTABILITIES SHOULD DECREASE. WILL KEEP THUNDER WORDING IN FOR FRI WITH LIKELY POPS. PRECIP LOOKS TO EVOLVE INTO POST FRONTAL NATURE LATER FRI NIGHT...WITH SOUTHERN THIRD OF CWA POSSIBLE EVEN GETTING DRY SLOTTED WITH A BREAK IN THE ACTION FOR AWHILE. AS FOR TEMPS...WILL LEAN TOWARD SLIGHTLY COOLER FAN HIGHS FOR THU WITH CONTINUING CLOUD COVER...ALTHOUGH SOME SUN IN LOCATIONS WILL SUPPORT LOCALLY WARMER READINGS. ...EXTENDED...SAT-SUN-MON... AS LONG RANGE MODELS CORRECTLY SLOW DOWN THEIR RESPECTIVE SOLUTIONS OF EJECTING SOUTHWEST SYSTEM OUT ACRS THE MIDWEST AT WEEK/S END...FEEL EVEN SLOWER MRF IN HANDLING ASSOCIATED SFC AND UPPER LEVEL SYSTEM BETTER. EUROPEAN...CANADIAN GEM AND MRF ALL PULL OUT CLOSED SOUTHWEST SYSTEM IN A NEGATIVELY TILTED FASHION AS IT TRIES TO PHASE WITH NORTHERN STREAM LATE FRI INTO SAT..BUT THEN WEAKEN IT QUICKLY AS IT FEELS BRUNT OF SHARP UPPER RIDGE TO THE EAST. WHILE CANADIAN AND EURO WHIRL SYSTEM AND IT/S ASSOCIATED MOISTURE THROUGH CWA QUICKER FOR A MAINLY DRY SAT...DO LIKE SLOWER MRF WITH LINGERING SHOWERS FOR SAT. ACTIVITY MAY BE RESTRICTED TO SAT MORNING AND MAY WORD 1ST DAY OF EXTENDED ACCORDINGLY. WITH CLOUDS AND LINGERING PRECIP...AS WELL AS CAA AT LOWER LEVELS...FEEL MILD MRF HIGH TEMP VALUES BIT HIGH FOR SAT. MRF...CANADIAN AND EURO ALL REASONABLY SIMILAR IN BUILDING LARGE PACIFIC NORTHWEST SFC HIGH ACRS THE UPPER MIDWEST SAT NIGHT AND SUN AS NEXT CUT-OFF SOUTHWEST SYSTEM DROPS DOWN AND SETS UP SHOP OVER THE NORTHERN BAHA. THIS WOULD INDUCE ANOTHER PERIOD OF UPPER RIDGING OVER THE MID TO UPPER MS RVR VALLEY THROUGH SUN...ALTHOUGH ACTIVE NORTHERN STREAM ACRS SOUTHERN CANADA LOOKS TO LIMIT NORTHERN EXTENT SOMEWHAT UNTIL SOUTHWEST SYSTEM STARTS TO PULL OUT. THUS DRY AND MILD WX APPEARS TO BE ON TAP FOR THE REST OF THE EXTENDED PERIOD. MRF AND EURO LOW LEVEL THERMAL PARAMETERS SUPPORT UPPER 50S-LOWER 60S ON SUN... ESPECIALLY WITH LATE MARCH INSOLATION. BOUNDARY LAYER AND H85 TEMPS CHANGE LITTLE...OR JUST WARM SLIGHTLY ON MON AS SFC RIDGE SLIDES ACRS THE EASTERN GRT LKS WITH A HINT OF RETURN FLOW BRUSHING THE CWA. .DVN... IA...NONE. IL...NONE. MO...NONE. HLADIK il AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 945 PM EST WED MAR 22 2000 AGAIN TONIGHT...THE FORECAST PROBLEM IS MAINLY ONE OF CLOUDS. THE BAND OF HIGHER RADAR REFLECTIVITIES WITH EMBEDDED SPRINKLES WHICH MOVED ACROSS THE NORTHERN DTX CWA HAS DWINDLED PRETTY MUCH OUT OF EXISTENCE. THIS MAY HAVE BEEN GENERATED BY WEAK FORCING FROM LEFT EXIT REGION OF UPPER JET PROGGED BY EARLIER RUNS AND SEEN ON 0Z RUC...IN PRESENCE OF RELATIVELY HIGHER 850 TO 700 MB MOISTURE... WEAKENING AS IT MOVED EAST AND AWAY FROM MORE FAVORED FORCING AND MOISTURE. SATELLITE LOOPS SHOW HIGH CLOUDS STARTING TO MOVE EAST OUT OF THE CWA...AND MUCH OF THE LOW CLOUDS CLEARING OUT AS WELL. MID CLOUD BAND MOVING SOUTHEAST OUT OF THE NORTHERN LAKES REGION THIS EVENING HAS BEEN PINCHING OFF TO LARGE DEGREE. OBSERVATIONS AND TRENDS SUGGEST A PARTLY CLOUDY OVERNIGHT...UNLESS STRATUS FILLS IN. LATEST RUC SOUNDINGS SUGGEST LOW LEVEL MOISTURE FOR MOST OF THE OVERNIGHT TRENDING TOWARD LESS...WITH MAINLY VERY SHALLOW MOISTURE. THIS...IN CONJUNCTION WITH LIGHT WINDS AND DEW POINT SPREADS ALREADY CLOSE...STILL WOULD POINT TOWARD FOG FORMATION AS THE NIGHT WEARS ON...BUT PROBABLY NOT TO WIDESPREAD DENSE FOG. THUS WILL UPDATE TO REFRESH CLOUD WORDING AND TO GO LIGHT WINDS...REST UNCHANGED. .DTX...NONE. DWD mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAND RAPIDS MI 937 PM EST WED MAR 22 2000 SEE NO REASON TO MAKE ANY MAJOR CHANGES TO THE GOING ZONE FORECAST... SO THIS UPDATE WILL BE PRIMARILY COSMETIC. LATEST SATELLITE IMAGERY AND SURFACE OBS INDICATE MAINLY MID AND HIGH CLOUDS OVER THE CWFA AT THIS TIME... WITH SOME LINGERING LOW CLOUD PATCHES. LOOKING UPSTREAM... THERE IS FAIRLY WIDESPREAD STRATOCU OVER WISCONSIN... WHICH IS TRYING TO MOVE ESE. THE LATEST RUC AND THE 18Z ETA BRING SOME OF THIS INTO OUR AREA OVERNIGHT... AND THAT SEEMS REASONABLE... PARTICULARLY NORTH OF I-96. IN ADDITION... THE 00Z SOUNDINGS INDICATED A MORE PRONOUNCED SUBSIDENCE INVERSION THAN THE EARLIER MODEL RUNS SUGGESTED... SO WE COULD EASILY SEE SOME LOW CLOUDS FILL BACK IN DURING THE OVERNIGHT HOURS. REGARDLESS OF THE LOW CLOUD ISSUES... WE SHOULD CONTINUE TO SEE SOME MID AND HIGH CLOUDS THROUGH THE NIGHT. WILL KEEP THE GOING THEME OF MOSTLY CLOUDY OR CONSIDERABLY CLOUDY. FORECAST TEMPERATURES LOOK FINE... AND LINE UP WELL WITH OBSERVED DEWPOINTS AROUND THE AREA... SO WILL LEAVE THOSE NUMBERS ALONE. IF WE LOSE ENOUGH CLOUD COVER... FOG (AND EVENTUALLY STRATUS) COULD BECOME A PROBLEM. WITH A CURRENT DEWPOINT DEPRESSION OF JUST A FEW DEGREES... AM NOT WILLING TO BANK AGAINST DENSE FOG... SO WILL LEAVE THE MENTION OF FOG IN THE FORECAST. ZONES WILL BE OUT BY 1000 PM. TRH .GRR...NONE. mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 415 PM EST WED MAR 22 2000 12Z RAOBS/LATEST WV LOOP SHOWS POLAR BRANCH FLOW ACRS SRN CAN WITH BLOCKY SRN STREAM FEATURING CUTOFF LOWS OVR SE AZ...NC CST AND WRN ATLANTIC NR BERMUDA. STRG SHRTWV EMBEDDED IN NRN BRANCH NOW MOVG THRU ONTARIO...BUT BEST DRYING/UPR CNVGC REMAINING TO N. CWA IN CONFLUENCE BTWN MORE WLY FLOW ACRS LK SUP AND MOIST SWLY FLOW IN WI ON NRN FLANK OF SFC HI TO S. ASSOCIATED MSTR CNVGC/ADVCTN ACRS CNTRL CWA HAS RESULTED IN STUBBORN LO/MID DECK OF CLD. BRK IN CLD WHICH HAD DVLPD ACRS NRN WI/SE ZNS HAS FILLED IN. NW PART OF CWA CLOSE ENUF TO UPR CNVGC ASSOCIATED WITH ONTARIO SHRTWV HAS CLRD OUT WITH STABILIZING OR DOWNSLOPE WLY FLOW OFF LK SUP. EDGE OF CLRG LINE MOVG SLOWLY EWD. FLOW ACRS NE MN STILL MAINLY WSWLY WITH SFC DWPTS THERE ONLY A BIT LWR THAN OVR CWA. MAIN FCST CONCERN TNGT IS CLD TRENDS/TEMPS. LATEST RUC AND 12Z ETA GUIDANCE SHOWS H925 WNDS TURNING MORE WNWLY ACRS NRN CWA THIS EVNG AS SHRTWV AXIS MOVES E OF CWA LONGITUDE. ALTHOUGH BEST UPR CNVGC REMAINS TO N...THIS FLOW SHUD ALLOW CLRG LINE TO PROGRESS FURTHER E WITH TIME...SO HAVE GONE MCLR/PCLDY IWD-KEWEENAW ZNS-MQT AND PARTIAL CLRG ALGER/LUCE. BUT SUSPECT CLD WL BE MORE STUBBORN ACRS SRN TIER WITH LLVL CNVGC AXIS REMAINING THERE. HI DWPTS UPWND REINFORCE CONFIDENCE CLD WL LINGER ACRS SRN TIER. FCSTG PTCHY FOG TO REDVLP THOSE PLACES THAT DIDN/T WARM/MIX SGNFTLY TDAY AND TEMPS GENERALLY NR MOS ACRS N WHERE SKIES CLR BUT ABV MOS TO S. ETA HAS HAD BEST HANDLE ON LLVL MSTR TRENDS LAST SVRL RUNS WITH DRYING MORE RELUCTANT TO SPRD S...SO FOLLOWED ITS GUIDANCE FOR CLD FCST TMRW. ETA 290K ISENTROPIC SFC PROGS SHOW INCRSG SLY COMPONENT AND MSTR RETURN DURG THU...SO HAVE KEPT SKIES MCLDY ACRS S AND WENT WITH BCMG MSTLY CLDY ACRS N. LACK OF ANY UPR DYNAMICS WITH BLDG HGTS/DRY MID/UPR LYRS WL PRECLUDE ANY PCPN. SINCE NGM IS SLOWER WITH MSTR RETURN...ASSUMING MORE CLD THAN FWC AND GOING WITH TEMPS LWR THAN FWC FOR MAX...ESPECIALL NR LK MI SHORELINE WITH SWLY FLOW GRDLY BCMG SE OFF COOL WATER. CONTD SWLY FLOW TMRW NGT...SO MORE CLDS WITH TEMPS A BIT ABV MOS GIVEN FCST LLVL DWPTS. ETA SHOWS AXIS OF HIER H85 DWPT/H100-7 MSTR CNVGC/H85-5 QVECTOR CNVGC MOVG THRU WCNTRL ZNS OVRNGT...SO ADDED MENTION OF SPRINKLES AFTR MIDNGT. MORE FOG FOR SE ZNS WITH CONTD MOIST FLOW ACRS LK MI. MODELS IN GOOD AGREEMENT ON TIMING OF SW CUTOFF WITH SYS PROGGED TO REACH NE KS BY F48. ETA SHOWS MSTR AXIS PASSING TO N DURG FRI MRNG... SO WORDED MRNG SPRINKLES WCNTRL. USED AVN FCST H2-3 DVGC TO TIME ARRIVAL OF SHRA CHCS OVR CWA...EARLY AFTN SW TO LATE IN DAY ACRS E. FCST MAX NR MOS GUIDANCE. EXTENDED MODELS NOW ALL IN AGREEMENT SHOWING SHRTWV IN NRN BRANCH APRCHG WRN LKS ON SAT AND AT LEAST PARTIALLY PHASING WITH REMNANTS OF SW LO LIFTING NEWD WHILE DEEP CUTOFF LO DVLPS OFF SE CAN. SINCE MRF ADVECTS H85 DWPT APRCHG 7C INTO SYS WITH SSI DOWN TO NR 0...WL UPGRADE SHRA THREAT TO LIKELY FOR FRI/SAT AS SFC WAVE MOVG IN ALG COLD FNT. MODELS ALSO INDICATE MDT CAD/DRYING IN ITS WAKE FOR SUN AS HI PRES BLDS IN. SINCE BLOCK OVR SE CAN APPEARS TO DVLP FAR ENUF S SO THAT NRN BRANCH CAN REMAIN MORE PROGRESSIVE AS MODELS FCST...WL REMOVE PCPN MENTION ON SUN FOR ALL BUT ERN ZNS EARLY WITH INCRSG SUNSHINE W-E. MODELS SHOW BLDG RDG OVR WCNTRL CAN AHD OF NXT SHRTWV SPINNING OFF GLFAK LO...WHICH ALLOWS FOR ENHANCED NWLY FLOW ACRS ERN CAN EARLY IN WEEK. A BACK DOOR TYPE COLD FNT MAY PASS MON-TUE AS SHRTWV DIGS SEWD...ESPECIALLY SINCE MRF/CANADIAN ENSEMBLES SHOW H5 TROF AXIS FARTHER W THAN OPERATIONAL MODELS. BUT WL KEEP PCPN OUT WITH DRY AIRMASS IN PLACE AND EVEN ERN CWA ON ACYC SIDE OF JET AXIS. COORDINATED WITH APX/GRB. .MQT...NONE. KC mi AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE JACKSON MS 1215 PM CST WED MAR 22 2000 SATELLITE INDICATES THAT CLOUDS CONTINUE TO RAPIDLY DECREASE OVER MUCH OF THE FORECAST AREA. LATEST RUC INDICATES CONTINUED MID/UPPER LEVEL DRYING ACROSS REGION THROUGH THE DAY. SATELLITE STILL SHOWS SOME MID LEVEL CONVECTIVE ELEMENTS OVER SW AND SE PARTS OF FORECAST AREA...SO WILL RETAIN SOME VERY LOW POPS THESE AREAS THIS AFTERNOON. ELSEWHERE...WILL GO MOSTLY SUNNY AND RAISE TEMPS A LITTLE. .JAN... MS...NONE. AR...NONE. LA...NONE. 08 ms AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE JACKSON MS 900 AM CST WED MAR 22 2000 SATELLITE THIS MORNING SHOWS THAT CONVECTION HAS DECREASED AND CLOUDS HAVE RAPIDLY THINNED OUT OVER THE FORECAST AREA. THE EXCEPTION IS THE FAR SOUTHERN COUNTIES WHERE A PERSISTENT BAND OF SHRA/TSRA CONTINUES TO SAG VERY SLOWLY SOUTH. RUC INDICATES A SERIES OF WEAK WAVES MOVING THROUGH RIDGE ACROSS AREA TODAY AND WITH SOME SCATTERED SHRA STILL UPSTREAM A CHANCE OF SHOWERS WILL PERSIST ACROSS THE FORECAST AREA TODAY. WILL UPDATE TO DECREASE CLOUDS AND POPS A LITTLE MOST AREAS BASED ON CURRENT TRENDS. WILL BREAK OUT A GROUP OVER THE FAR SOUTH TO GO LIKELY POP THIS MORNING. NO OTHER CHANGES. .JAN... MS...NONE. AR...NONE. LA...NONE. ms CENTRAL PENNSYLVANIA FORECAST DISCUSSION NATIONAL WEATHER SERVICE STATE COLLEGE PA 930 PM EST WED MAR 22 2000 PLENTY OF LOW LEVEL MOISTURE STILL TRAPPED UNDER INVERSION THIS EVENING. THERE HAS BEEN SOME DECENT CLEARING OVER THE LOWER SUSQ VALLEY THIS EVENING...PICKED UP WELL BY THE LATEST RUC. THE RUC SHOWS THIS LOW LEVEL MOISTURE RETURNING OVERNIGHT. THIS...COUPLED WITH SOME MID CLOUDS DRIFTING ACROSS THE AREA...WILL GO WITH VARIABLE CLOUDINESS WORDING IN THE EAST...AND MOSTLY CLOUDY IN THE WEST. DO NOT SEE SIGNIFICANT DRYING OF LOW LEVELS TONIGHT WITH NEARLY CALM SURFACE WINDS. THEREFORE...BUMPING UP OVERNIGHT LOWS IN MOST AREAS EXCEPT THE NORTHEAST...AS DEWPOINTS RUNNING AROUND 40 THROUGHOUT THE CWA. FOG SHOULD BE DEVELOPING...ESPECIALLY WHERE SKIES GO PARTLY CLOUDY. WILL KEEP UP DENSE FOG ADVISORY FOR THE LAURELS OVERNIGHT WITH SNOW COVER STILL PRESENT. HYDRO... STILL SOME MINOR FLOODING OF TRIBUTARIES OF THE MAIN STEM SUSQ ACROSS SE PORTION OF CWA. SEE PHLFLSCTP FOR DETAILS. .CTP...NPW FOR DENSE FOG ADVISORY TONIGHT...PAZ024-033. JUNG pa AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE COLUMBIA SC 920 PM WED MAR 22 2000 LOW LVL DIVG NOTED EARLIER TOD OVR CWA WITH RELAXED PRESS GRAD IN BETWEEN LOW PRESS OFFSHR NC CST...RIDGING INTO WRN NC/VA...AND INVERTED TROF OVR GA. SATL INDICATES SC CLDS ACRS ERN HALF NC...HAVING A HARD TIME MOVG SW INTO CWA/LOW LVL DIVG AREA. LTST RUC/MESOETA STILL INSIST ON INCR SFC-850 RH LATE TON...AND VEERING THE WIND TO ENE. LOW OFFSHR NC CST TO MOVE SOUTH AND WEAKEN...WITH SFC TROF SWINGING SW TOWARDS CWA...ALLOWING LOW LVL DIVG OVR SC TO BE REPLACED BY CONVG AND VEERING WIND. LTST MSAS MSLP ANAL CONFIRMS PRESS GRAD BEGINNING TO INCR OVR CWA. HOWEVER...EVEN LTST RUC HAD MOISTURE INCR INTO NE CWA BY NOW...AND SATL CONFIRMS CLDS STILL NOT MAKING IT. PREMISE FOR INCR IN LOW LVL CLDS STILL LOOKS GOOD FOR LTR TON AND INTO FRI...BUT NOT SURE IF CLDS WILL BE SCT OR BKN TON...SO WILL JUST WORD IT INCR CLDNS SINCE WE'RE SKC ATTM. AS FAR AS TEMPS GO...INCR PRESS GRAD MEANS SOME WIND. THIS ALG WITH SOME CLDS SHOULD KEEP TEMPS HIGHER THAN OUR 40 THIS MORN...EVEN THO NE FLOW IS A CAA FLOW. LOOKING AT LTST MDL PROJ...GOING FCST OF MID 40S TON ALSO CONT TO LOOK OK. MAY RAISE TO 45 TO 50. .CAE...NONE. MILLER sc AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA NATIONAL WEATHER SERVICE SIOUX FALLS SD 1035 AM CST WED MAR 22 2000 VISIBLE SAT LOOPS SHOWING SOME DISSIPATION TO CLOUDS ALONG AND WEST OF KMML TO KYKN LINE. WOULD EXPECT TREND TO CONTINUE BASED ON DECREASING LOW LEVEL RH FORECAST FROM 12Z RUC. 12Z RAOBS FROM KABR AND KOMA INDICATE POTENTIAL TO REACH 60 DEGREES...POSSIBLY EVEN TOP IT IN THE WEST WHERE SUNSHINE WILL BE MROE PREVALENT. WITH PARTIAL SUNSHINE EXPECTED THIS AFTERNOON...WILL UPDATE TO RAISE TEMPS A BIT MOST AREAS. THICKER CLOUDS AND STILL SOME LOW STRATUS/FOG OVER MOST OF NWRN IA...AND SMALL PART OF SWRN MN...WILL PERSIST LONGER AND KEEP TEMPS DOWN A LITTLE FROM AREAS FARTHER WEST. ALSO A FEW LIGHT RAIN SHOWERS ON KOAX RADAR AROUND AND JUST SOUTH OF KSUX AREA...SO WILL PUT A MENTION OF THIS IN KSUX ZONE THROUGH EARLY AFTN. .FSD...NONE HAMEN sd AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MORRISTOWN TN 1000 AM EST WED MAR 22 2000 LATEST RUC AND MESO-ETA CONTINUE TO SHOW WEAK 925-MB THERMAL TROUGHING AND NORTHEAST FLOW DOWN THE NORTHERN TENNESSEE VALLEY THIS MORNING...INCLUDING SECTIONS OF SOUTHWEST VIRGINIA. THESE SHORT-TERM MODELS WEAKEN THE THERMAL TROUGHING AND RELATIVE HUMIDITY THIS AFTERNOON. HOWEVER...THE SWATH OF LOW CLOUDS ON THE BACK SIDE OF THE MIDDLE ATLANTIC COASTAL LOW IS QUITE IMPRESSIVE. SO...FOR THIS AFTERNOON...WILL MAINTAIN THE MOSTLY CLOUDY WORDING IN THE NORTHEAST. ELSEWHERE...EARLY 22/12Z MODEL INFORMATION IMPLIES MOSTLY SUNNY AFTERNOON SKIES. HOWEVER...CONSIDERING THAT CLOUDS FROM THE NORTHEAST ARE EFFECTIVELY ADVECTING SOUTHWEST...WILL MAINTAIN THE PARTLY SUNNY WORDING. IN TERMS OF TEMPERATURES...WILL LOWER FIRST PERIOD MAXES A LITTLE. .MRX... NC...NONE. TN...NONE. VA...NONE. DM tn AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE FORT WORTH TX 940 PM CST WED MAR 22 2000 EVENING ANALYSIS LEAVES US WITH THE FOLLOWING INFORMATION: A VERTICALLY DEEP RIDGE ALOFT HAS INTENSIFIED FROM THE NORTHERN GULF INTO THE MISSISSIPPI RIVER VALLEY. THIS WILL BLOCK EASTWARD MOTION OF THE UPPER LOW TO OUR WEST. MEANWHILE...STRONG HEIGHT FALLS HAVE ENTERED THE PACIFIC NORTHWEST...AND THIS WILL FORCE THE UPPER LOW OUT OF ITS CURRENT POSITION. THE ONLY PLACE FOR THE SYSTEM TO MOVE IS NORTH-NORTHEAST...THUS JUST GRAZING THE NORTH CENTRAL TEXAS AREA. MESOSCALE MODELS (E.G. RUC II) WANT TO KEEP ALL OF THE PRECIP WEST OF OUR AREA...BUT THE OLD SUPERCELLS HAVE MELDED INTO A SEVERE SQUALL LINE THAT IS PUSHING EAST ON ITS ON OUTFLOW (SOMETHING THE MESOSCALE MODELS HAVE NOT CAUGHT ONTO). WE THINK THAT THIS SQUALL LINE WILL REACH NORTH CENTRAL TEXAS...AND DIE FOR LACK OF SUPPORT. OR...IT MAY BECOME STRUNG OUT SW-NE WITH CELL TRAINING AND A HEAVY RAIN THREAT TAKING OVER LATE TONIGHT. AS THE SQUALL LINE WEAKENS LATE TONIGHT...A NEW LINE OF STORMS MAY DEVELOP THURSDAY MORNING/ AFTERNOON...AND MOVE RAPIDLY NORTHEAST INTO OKLAHOMA. IT IS DIFFICULT TO TELL AT THE CURRENT TIME...BUT THURSDAY'S STORMS MAY NOT REACH VERY FAR SOUTH INTO SOUTHERN SECTIONS OF NORTH TEXAS. WE WILL UPDATE THE FORECAST BASED ON THESE POSSIBLE SCENARIOS... WITH THE HIGHEST POPS IN THE NORTH AND WEST. THERE STILL IS SOME LOW TORNADO THREAT IN THE WEST...BUT NOT NEARLY AS MUCH AS EARLIER THIS EVENING IN THE AREAS NORTH OF SAN ANGELO AND EAST OF MIDLAND. .FTW...CAUTION ON AREA LAKES TONIGHT WEST AND CENTRAL. 26 tx AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE LUBBOCK TX 820 PM CST WED MAR 22 2000 LINEAR MESOSCALE CONVECTIVE SYSTEM (MCS) HAS DEVELOPED ACROSS THE EASTERN ZONES. SEVERAL SEVERE THUNDERSTORMS ARE EMBEDDED IN THE LINE OF DEEP CONVECTION ALONG THE LEADING EDGE OF THE MCS. DEEP CONVECTION CONTINUES TO PROPAGATE EAST INTO ENVIRONMENT CHARACTERIZED BY INFLOW OF HIGH LOW-LEVEL THETAE AND STRONG VERTICAL WIND SHEAR. MAIN SEVERE WEATHER THREAT THUS LOOKS TO BE EAST OF OUR AREA AT THIS TIME. IN ITS WAKE, PERSISTENT LIGHT TO MODERATE RAIN WAS NOTED, GENERALLY EAST OF I-27. FLASH FLOOD WATCH STILL OK, ALTHOUGH AT THIS POINT THE WESTERN PART OF THE WATCH IS TO COVER POTENTIAL FOR LATE NIGHT ACTIVITY. MEANWHILE, UPPER LOW LOOKS TO HAVE REFORMED A LITTLE EAST INTO SOUTHWEST NEW MEXICO. THIS IS IN LINE WITH EARLIER PROGS, AS WELL AS 18Z MESOETA AND LATEST RUC WHICH BEGINS TO PULL SYSTEM NORTHEAST OVERNIGHT. RUC MOVES STRONG SURFACE LOW TO THE NORTH, LEADING TO STRONG BOUNDARY LAYER WARM ADVECTION, ESSENTIALLY REORIENTING THE LOW LEVEL BAROCLINIC ZONE FROM NORTHEAST-SOUTHWEST, TO NORTH-SOUTH ALONG OUR WESTERN ZONES. DESPITE THE CURRENT LULL IN ACTIVITY WEST OF THE MCS, SOME REDEVELOPMENT IS POSSIBLE OVERNIGHT (MAYBE SEVERE AS STEEP LAPSE MOVES EAST) ACROSS WESTERN HALF OF THE AREA AS THE UPPER SYSTEM MOVES NORTHEAST. HOWEVER, THE EXISTING MCS MAKES CONFIDENCE IN PROGGED EVOLUTION OF SURFACE FEATURES UNCERTAIN AT BEST. WILL LOWER POPS A LITTLE ACROSS WESTERN ZONES, OTHERWISE NO LARGE SCALE CHANGES EXPECTED FOR NOW. .LBB...FLASH FLOOD WATCH TONIGHT ZONES 23>26-29>32-35>38-41>44 tx AREA FORECAST DISCUSSION...UPDATE NATIONAL WEATHER SERVICE LUBBOCK TX 1245 PM CST WED MAR 22 2000 RUNNING BEHIND THE POWER CURVE SO WILL KEEP THIS SHORT. LATEST SURFACE ANALYSIS SHOWS COLD FRONT JUST SOUTH OF AN ALTUS TO HOBBS TO KGDP LINE AT 18Z. WARM FRONT WAS LOCATED FROM SOUTH OF MIDLAND TO BETWEEN ABILENE AND SAN ANGELO. THUNDERSTORMS ARE FORMING JUST NORTH OF THE WARM FRONT NORTH OF MIDLAND ATTM. WITH MEAN STEERING FLOW FROM THE SOUTH EXPECT THIS ACTIVITY WILL MOVE NORTHWARD AND INCREASE AS IT MOVES TOWARD THE SOUTH PLAINS. UPPER LOW IS OVER SOUTHEAST ARIZONA ATTM AND HAS NOT SHOWN AN EASTWARD MOVEMENT YET BUT IS EXPECTED TO KICK OUT TO THE EAST ACROSS SOUTHERN NEW MEXICO TONIGHT. ELEVATED SEVERE THUNDERSTORMS ARE THE MAIN CONCERN FOR THIS AFTERNOON AND EVENING THEN TURNING INTO HEAVY RAIN EVENT TONIGHT. 15Z RUC SHOWS UNSTABLE AIRMASS WILL ADVECT NORTHWARD INTO THE REGION ABOVE THE SHALLOW COLD AIR AT THE SURFACE. THIS IS DEPICTED BY SHOWALTER INDICES DECREASING TO A -5 TO -9 DEGREES RANGE BY 03Z FROM THE SOUTHEAST TEXAS PANHANDLE SOUTH-SOUTHWEST TO THE PERMIAN BASIN. COUPLED UPPER LEVEL JET STRUCTURE WILL MAXIMIZE THE UPPER LEVEL DIVERGENCE OVER THE AREA BY 06Z. LIFT ASSOCIATED WITH LOW LEVEL WARM AIR ADVECTION/ISENTROPIC UPGLIDE WILL INCREASE OVER THE SOUTH PLAINS TONIGHT. 12Z AVN MODEL CONTINUES TO BULLSEYE A REGION OF 20 MICROBARS/SECOND AT 06Z. WILL CONTINUE MENTION OF LOCALLY HEAVY RAINFALL TONIGHT. DUE TO ELEVATED NATURE OF STORMS LARGE HAIL APPEARS TO BE THE MAIN SEVERE THREAT FOR MOST OF THE SOUTH PLAINS AND ALL OF THE LOW ROLLING PLAINS THIS AFTERNOON AND EVENING. .LBB...NONE. TINSLEY tx EXTREME SOUTHWESTERN CALIFORNIA AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SAN DIEGO CA 945 PM PST WED MAR 22 2000 INCREASING ONSHORE FLOW AND A DEEPENING MARINE LAYER WILL BRING A RETURN OF COASTAL LOW CLOUDS AND A COOLING TREND TO SOUTHWEST CALIFORNIA THROUGH FRIDAY. A GULF OF ALASKA STORM WILL MOVE INTO SOUTHERN CALIFORNIA SATURDAY AND SUNDAY BRINGING SHOWERS...COOLER TEMPERATURES...AND A CHANCE FOR THUNDERSTORMS TO SOUTHWEST CALIFORNIA. IN THE NEAR TERM...RUC IS FORECASTING A CSTL EDDY TO DEVELOP LATE TONIGHT...DECAYING THU MORNING. SYNOPTIC PATTERN WITH PROGRESSION OF A PAC SHORTWAVE INLAND INTO THE PAC NW SUPPORTS THIS SCENARIO. EARLY EVENING ACARS SOUNDINGS SHOW THE BASE OF THE MARINE INVERSION AOB 1000 FEET MSL. WITH HEIGHTS ALF CHANGING LTL OVERNIGHT OR LWRG ONLY SLIGHTLY...NOT MUCH DEEPENING OF THE MARINE LYR IS EXPECTED. THIS SUPPORTS POTENTIAL FOR LCLLY DENSE FOG ALG THE CST LATE TONIGHT INTO THU MORNING. EXPECT GREATEST COVERAGE OF LOW CLOUDS OVR NRN ORANGE COUNTY AND SRN LOS ANGELES COUNTY PER 18Z ETA LOW LVL (975 MB) RH PROGS. SOME ADDITIONAL DEEPENING OF MARINE LYR THU NIGHT AND FRI AS HEIGHTS GRADUALLY LWR AND ONSHR FLOW INCREASES. EARLIER FORECAST MAY HAVE BEEN A LTL AGGRESSIVE WITH THE DEGREE OF DEEPENING FOR THU NIGHT THRU FRI MORNING. MORE SUBSTANTIAL DEEPENING IS POSSIBLE FRI NIGHT THRU SAT MORNING AS THE WEEKEND GULF OF AK STORM APPROACHES. IN THE EXTENDED...NEW AVN IN GOOD AGREEMENT WITH PREVIOUS MRF. ECMWF IS TRENDING A LTL FARTHER W WITH CLOSED UPR LOW FOR THE WEEKEND...SIMILAR TO THE MRF. RAIN SHOULD SPREAD INTO SW CA DURG THE DAY SAT WITH SHOWERS TO CONTINUE INTO SUN. IT IS WORTH NOTING THAT A PERFECT PROG AVN WOULD BE VERY CLOSE TO THE SYNOPTIC PATTERN FAVORABLE FOR WATERSPOUT DEVELOPMENT OVR THE SRN CA CSTL WTRS SAT AFTERNOON AND EVENING. AS THE MID LVL COLD POOL MOVES TO THE VCNTY OF SRN CA SAT NIGHT AND SUN...THUNDERSTORMS ARE ALSO POSSIBLE. SAN 0000 .SAN...NONE. MARTIN ca NORTHEAST AND NORTH CENTRAL COLORADO AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DENVER COLORADO 300 AM MST THU MAR 23 2000 SHORT TERM DISCUSSION: WINKEN...BLINKEN AND NOD OR ARE THEY 3 PEAS IN A POD? THAT IS THE STORY OF ETA...NGM AND AVN MODELS FOR TODAY REGARDING THE UPPER LOW LIFTING NEWD TO NEAR AMA ABT 18Z AND TO WRN OK ABT 00Z FRI. THEY AGREE ALMOST EXACTLY WRT POSITION. LATEST RUC ALSO IN AGREEMENT FOR THE 12 HOURS IT COVERS. THE MDLS ARE ALSO ON THE SAME PAGE REGARDING SFC PTRN WITH LOW LIFTING NEWD FROM NM AND A TROF FROM ERN WY TO AKO AND THEN TO SFC LOW. ZONES W OF THIS TROF TO BE IN DWNSLP NWLY PTRN WHILE POINTS E WILL BE IN S-SELY FLOW TODAY. THIS ALSO SEPARATES LOWER RH FROM HIER RH AND WILL ALSO BE MY LINE OF DEMARCATION FROM NIL POPS TO SCT POPS. DO NOT HOW ANY PCPN WILL OCCUR W OF TROF LINE WITH NO DYNMCS...LMTD RH AND DWNSLP FLOW AND WILL DROP FROM FCST. E OF LINE IN ZONES 48...49...50 ENUF MSTR AND DIURNAL INSTBY TO RIDE WITH 40% POPS OR HIER FOR THIS AFTN. AS FOR MTNS SEE NO NEED TO GO HEAVY ON POPS THERE DESPITE DEFORMATION ZONE MVG INTO AREA. DO NOT SEE ENUF MSTR TO GO MORE THAN WDLY SCT AND THAT MAY BE STRETCHING IT. APPEARS FWC AND FAN ARE TOO OPTIMISTIC TODAY WITH TEMPS SINCE CLOUD COVER TO BE THICK ENUF TO HINDER WARMING THRFR WILL UNDERCUT BY SVRL DEGREES. BOODA LONG TERM DISCUSSION: LINGERING EFFECTS OF CLOSED LOW WL EXIT STAGE RIGHT THIS EVENING AS ALL MDLS SHIFT THIS FEATURE E INTO CNTRL KS BY 06Z TNGT. WL HOLD ONTO SOME CLD CVR AND LOW POPS ACRS FAR ERN ZONES THIS EVENING...BUT DROP ANY MNTN OF PCPN ELSEWHERE. SHORT WAVE RIDGING DVLPS OVR THE CWA TNGT AS THE DEFORMATION ZONE SHIFTS TO THE E AND DRIER W-NWLY FLOW ALF DVLPS. NEXT PACIFIC STORM SYSTEM WL BRUSH ACRS CO FRIDAY MRNG. WEAK UPR LVL DYNAMICS AND MARGINAL MID LVL INSTBY WL PROBABLY NOT AMOUNT TO TOO MUCH SHOWER ACTIVITY IN THE MOUNTAINS. MAIN EFFECT FROM THIS FTR IN THE PLAINS WL BE THE PASSAGE OF A COLD FRONT THAT IS PROGGED TO SLIP SOUTHWARD INTO THE NERN PLAINS ARND 18Z. AS A RESULT WARMUP ACRS THE PLAINS MAY BE STUNTED SOMEWHAT ON FRI. AVN INCREASES BNDRY LYR RH ACRS THE NERN PLAINS FRI NIGHT AS LOW LVL WINDS BECOME SELY...SO MAY NEED TO BE CONCERNED WITH STRATUS AND/OR FOG DVLPG AT THAT TIME. AVN INDICATES AN INCRG SWLY FLOW ALF OVR CO SATURDAY AFTN WITH SFC LEE TROF DVLPG ALG THE FOOTHILLS. BEST TEMPERATURE RECOVERY SHUD OCCUR AT THAT TIME. LATEST MRF RUN CONTINUES TO CLOSE OFF THE NEXT SYSTEM THAT DROPS INTO THE DESERT SW...SWINGING IT ACRS CNTRL NEW MX SUNDAY INTO MONDAY. THE TIMING OF THE LATEST RUN IS FASTER THAN THE PRVS RUN ...BUT BASED ON THE HISTORY OF THESE CLOSED SYSTEMS...I SUSPECT THE SLOWER SOLUTION OF THE PRVS MRF RUN IS PROBABLY BETTER. THEREFORE ...WL LEAVE THE EXTENDED FCST AS IS FOR NOW. COOPER .DEN...NONE. co WESTERN COLORADO & EASTERN UTAH AREA FORECAST DISCUSSION...CORRECTION NATIONAL WEATHER SERVICE GRAND JUNCTION CO 250 AM MST THU MAR 23 2000 UPPER LOW HAS FINALLY RELINQUISHED CONTROL OF THE FORECAST AREA LEAVING LOTS OF LOW CLOUDS IN THE MOIST ATMOSPHERE SOUTH. FOG LIKELY TO PERSIST THERE THIS MORNING AFFECTING MAX TEMPERATURES JUST A BIT. 06Z RUC AND ETA INDICATE LOWER LEVELS REMAIN MOIST ENOUGH AND UPPER LEVELS COOL ENOUGH FOR SOME INSTABILITY MTN SHOWERS THIS AFTERNOON. NEXT TROF IS SHOWING SIGNS OF SPLITTING AS IT PRODUCES ONLY LIGHT PRECIP ACROSS OR-NORTHERN CA THIS MORNING. NORTHERN-BRANCH PORTION BRINGS MOISTURE AND LIFT TO NW FA TONIGHT. AT 06Z FRONT APPROACHING BOISE...WITH PASSAGE EXPECTED IN THE EASTERN UINTA MTNS AROUND SUNSET...AND STRETCHED ACROSS NORTHERN COLORADO BY FRIDAY MORNING. NGM INDICATES FRONT TO SAG JUST SOUTH OF GJT...BUT ETA/AVN KEEP FRONT JUST NORTH...ALONG THE TAVAPUTS OR BOOKCLIFFS. LIGHT PRECIP POSSIBLE FOR NORTHERN ZONES...MAINLY MTNS TONIGHT-FRIDAY. EXTENDED: AVN/MRF IS COLDER AND DEEPER THAN ETA/NGM WITH NEXT SYSTEM AS IT APPROACHES THE NW COAST FRIDAY AFTERNOON. GOOD AGREEMENT WITH PREVIOUS MRF AND EC THRU SUNDAY MORNING AS THE LOW CLOSES OVER SOUTHERN CALIFORNIA...BUT THEN EJECTS FASTER. WITH ETA/NGM/OLD MRF/EC ALL LINING UP FOR SLOWER SOLUTION...EXPECT LOW TO TRACK THRU SOUTHERN NM MONDAY NIGHT. TREND IS FOR THIS SYSTEM TO BE NOT QUITE AS POTENT AND COLD AS THE PREVIOUS. MOST PRECIP EXPECTED SUNDAY-MONDAY WITH THE EMPHASIS SOUTH. REMARKABLY GOOD AGREEMENT FOR THE REMAINDER OF THE NEW WEEK. NEXT CLOSED LOW TRACKS A LITTLE FURTHER INLAND AND KEEPS REGIONAL WEATHER IN UNSETTLED MOIST SW FLOW THRU FRIDAY. 99/RAMEY .GJT...NONE. WESTERN COLORADO AND EASTERN UTAH EMERGENCY MANAGERS SHOULD MAINTAIN A NORMAL LEVEL OF WEATHER AWARENESS TODAY. co AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TALLAHASSEE FL 215 AM EST THU MAR 23 2000 FORECAST CHALLENGE -- CLOUDS AND FOG. --CURRENTLY-- SATELLITE SHOWS SRN STREAM UPPER LOW OVER SW USA BEGINNING TO LIFT NE AS STRONG VORT MAX ROUNDS BASE. LATENT HEAT FROM STRONG/SEVERE CONVECTION OVER W TX IS HELPING TO AMPLIFY THE DOWNSTREAM RIDGE LOCATED JUST UPSTREAM OF OUR CWA. A STRONG NRN STREAM UPPER SHORTWAVE TROUGH IS CURRENTLY OVER THE PACIFIC COAST MOVING ONSHORE. THIS FEATURE SHOULD EVENTUALLY PHASE WITH AFOREMENTIONED LOW OVER THE SW. ANOTHER UPPER LOW OVER THE ATLANTIC WELL OFFSHORE FROM THE CAROLINAS CONTINUES TO SWING S. SURFACE DATA SHOW DAMMED COOL AIR MASS E OF THE APPALACHIANS HEADING SW TOWARD THE CWA. ASSOCIATED LOW CLOUDS DO NOT SEEM TO BE MAKING MUCH PROGRESS OUT OF THE CAROLINAS. --FORECAST-- SHORT TERM - 23/01Z RUC PROGS STRONGER NE SURFACE FLOW TO REACH ERN CWA LATER THIS MORNING WITH FRONT. BUOY #42036 W OF TPA ALREADY SHOWING A RECENT INCREASE IN N WINDS OVER THE LAST COUPLE HOURS. SATELLITE AND SATURATION VAPOR PRESSURE DEFICIT PROGS (SVPDP'S) SUGGEST LOW CLOUDS SHOULD NOT BE AN IMMEDIATE PROBLEM...BUT METARS AND SURFACE SVPDP'S SUGGEST PATCHY FOG MAY BE SEEN OVER PARTS OF OUR ERN ZONES THIS MORNING. TODAY AND FRIDAY - UPPER LOW OVER SW USA TO SHEAR NE AND WEAKEN THROUGH FRIDAY...WHILE DOWNSTREAM RIDGE OVER THE ERN US FLATTENS. SURFACE WINDS OVER CWA TO VEER TO A MORE ELY DIRECTION THROUGH FRIDAY AFTER BACK DOOR FRONT PASSES AND SURFACE RIDGE AXIS BUILDS SW INTO CWA. WRN EDGE OF LOW CLOUDS OVER ATLANTIC CURRENTLY MATCHES 70% 1000-850MB MEAN RH CONTOUR SEEN ON MODEL PROGS. THIS MOISTURE IS FORECAST TO SPREAD W INTO ERN CWA FROM JAX AREA OVERNIGHT. WILL THEREFORE WORD MORNING LOW CLOUDS FOR ERN ZONES ONCE AGAIN. BOUNDARY LAYER MOISTURE TO ALSO INCREASE IN REST OF ZONES. SKIES SHOULD STAY FREE OF HIGH CLOUDS TONIGHT WITH SHARP UPPER RIDGE UPSTREAM...SO COULD SEE PATCHY RADIATION FOG IN ZONES FARTHER W. IN SPITE OF ETA PROGS OF PRECIPITATION JUST E OF OUR CWA...BELIEVE ENTIRE FORECAST PERIOD SHOULD STAY DRY. MARINE - AS NOTED EARLIER...W TPA BUOY WINDS HAVE COME UP. WILL MENTION SMALL CRAFT EXERCISE CAUTION FOR AT LEAST ERN ZONES TODAY. FIRE WEATHER - WILL BE A MARGINAL SITUATION FOR LOW RH DURATIONS THIS AFTERNOON...SO WILL CONTINUE FIRE WEATHER WATCH. EXTENDED (FRIDAY NIGHT THROUGH MONDAY) - SURFACE RIDGE AXIS TO CENTER OVER CWA THROUGH SUNDAY. MRF ADVERTISES A COLD FRONT TO PASS S THROUGH CWA MONDAY...BUT WITH SHALLOW MOISTURE TO WORK WITH AND AN UPPER RIDGE UPSTREAM...RAIN PROSPECTS WITH THIS FEATURE DO NOT LOOK PARTICULARLY GOOD. WILL THEREFORE KEEP EXTENDED DRY FOR NOW. USED A GUIDANCE/PERSISTENCE BLEND FOR TEMPERATURES. ALL INPUT IS WELCOME. PRELIMINARY NUMBERS... TLH 079/051 076/052 0000 PFN 078/056 076/058 0000 DHN 078/054 078/054 0000 ABY 072/051 075/052 0000 VLD 075/050 079/050 0000 .TLH... AL...NONE. GA...NONE. FL...FIRE WEATHER WATCH THIS AFTN ALL ZONES EXCEPT FLZ012-014-015. TJT fl AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DULUTH MN 245 AM CST THU MAR 23 2000 FORECAST CONCERNS ON MORNING FOG AND SKY CONDS TODAY...THEN PRECIP CHCS LATER TONIGHT AND FRIDAY. 11u-3.9u IMGS SHOW 50FT CLOUD DECK LIFTING NE AT AROUND 20 MPH. ETA/RUC SEEM TO HAVE A GOOD HANDLE ON THIS H8 MSTR...SPRDG OVR ALL OF OUR SRN CWA THIS AM AND NRN PTNS LATE. WK FLOW AND CLR SKIES N OF THIS AREA...HELPG RADIATIONAL FOG TO DVLP. HOWEVER EXPECT CLOUDS MOVING ACROSS THE AREA TO PREVENT ANY WIDESPREAD DENSE FOG. ETA SHOWS DRY H8 PUNCH LIFTING N ACROSS WI LATE IN THE DAY...WITH SHALLOW H7 MSTR SPREADING ACROSS THE RGN. FOR NOW WILL KEEP SKIES MOCLDY SKIES GOING S AND CONT INCRG TREND N. MAY GO WITH PTSUNNY WORDING E LATE. WILL LEAVE SLIGHT POP SW LATE THIS AFTN...ALTHU MAIN FORCING SETS UP WEST. TONIGHT...MDLS SMLR WITH GOOD FORCING ACROSS ERN DAKOTAS AND NW MN NR CDFNT. DRIER SE FLOW SHOULD HOLD POPS DOWN MOST PLACES E. ON FRIDAY...UPR TROF WEAKENS AS LIFTS NE INTO RDG. RIGHT NOW LOOKS LIKE BEST FORCING ALNG AND JUST AHEAD OF CDFNT WHICH REACHES N CNTRL MN BY 00Z FRIDAY. WILL KEEP HIGHEST POPS W LATER TONIGHT AND FRIDAY...AND HOLD OFF LIKELY POPS EAST UNTIL LATE FRIDAY AND FRIDAY NIGHT. WITH LACK OF DAYTIME HEATING INSTABILITY PARMS NOT ALL THAT IMPRESSIVE THROUGH THE PD. CANADIAN AND NOGAPS NOT AVAILABLE AND THUS WILL LIMIT ANY CHANGES TO EXTENDED. STUCK CLOSE TO NGM/AVN GUIDENCE. TOMALAK .DLH...NONE mn AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE EL PASO TX/SANTA TERESA NM 216 AM MST THU MAR 23 2000 SYNOPSIS... A LOT MORE SUN WILL SHINE OVER THE AREA TODAY AS THE STATIONARY UPPER LEVEL STORM SYSTEM THAT AFFECTED OUR WEATHER THE PAST TWO DAYS WILL FINALLY MOVE EAST OF THE AREA. WITH ONLY A FEW LINGERING CLOUDS OVER MOST OF THE REGION THE INCREASED SUNSHINE WILL WARM TEMPERATURES BACK UP TO LATE MARCH NORMALS. IT WILL BE SLIGHTLY BREEZY IN THE AFTERNOON AS SURFACE LOW PRESSURE EAST OF THE REGION WILL HELP INCREASE WEST WINDS TO THE 15 TO 25 MPH RANGE. THROUGH THE REST OF THE WEEK AND INTO THE WEEKEND CONDITIONS OVER THE AREA WILL REMAIN DRY WITH ONLY HIGH MOSTLY THIN CLOUDS FROM TIME TO TIME. TEMPERATURES WILL WARM IN SOUTHWEST FLOW ALOFT. EXPECT SOME AFTERNOON BREEZES AND HIGH CLOUDS ON SATURDAY AS A WEAK UPPER LEVEL DISTURBANCE PASSES OVER. DISCUSSION... AFTER SPINNING IN PLACE ALL DAY WEDNESDAY...QUASI-STATIONARY UPPER LEVEL STORM SYSTEM IS NOW SHOWING A SHIFT TO THE EAST. AVN/ETA/NGM ALL SHOWING SYSTEM PUSHING EAST ACROSS SOUTHERN NEW MEXICO. THEY DID HOWEVER INITIALIZE THE LOW CENTER TOO FAR SOUTH. RUC HAS UPPER LOW BETTER PIN POINTED. WATER VAPOR SAT IMAGERY SHOWING DRY SLOT CUTTING THROUGH FORECAST AREA (FA) WITH MINIMAL WRAP-AROUND STILL TO CLEAR FA. GILA AREA STILL REPORTING A FEW LIGHT SNOW SHOWERS AROUND MIDNIGHT. THESE SHOULD END PRIOR TO THIS PACKAGE RELEASE. I EXPECT A BIT OF RESIDUAL LOW TO MID LEVEL MOISTURE TO RESULT IN A SPARSE CU FIELD BY LATE MORNING...BUT IT SHOULD DISSIPATE AS THE DAY WEARS ON AS TEMPERATURES ALOFT WARM AND MOISTURE CONTINUES TO SHIFT EAST OUT OF THE FA. MORE HIGH CLOUDS INCOMING FROM THE SOUTHWEST...BUT STILL KEEP IT MOSTLY SUNNY TODAY. AFTER LOW CLEARS THE AREA THIS AFTERNOON...A SHORT PERIOD OF VERY WEAK RIDGING TONIGHT...BEFORE GENERAL UPPER LEVEL SOUTHWEST FLOW DEVELOPS. THIS WILL HELP CONTINUE THE WARMUP THAT WILL START TODAY. PERIODS OF UPPER LEVEL CLOUDINESS WILL PERSIST. NEXT SYSTEM PROGGED TO AFFECT THE AREA IS DUE MONDAY...WILL MENTION PC AND WINDY FOR THAT DAY. EL PASO UB 67/ 40/ 75/ 45/ 75 00000 LAS CRUCES UB 65/ 32/ 73/ 37/ 73 00000 ALAMOGORDO UB 64/ 35/ 72/ 40/ 72 00000 CLOUDCROFT BB 44/ 21/ 52/ 26/ 52 10000 TRUTH OR CONSEQUENCES UB 66/ 35/ 74/ 40/ 74 00000 SILVER CITY UB 55/ 27/ 63/ 32/ 63 -0000 DEMING UB 64/ 32/ 72/ 37/ 72 00000 LORDSBURG UB 65/ 31/ 73/ 36/ 73 00000 SIERRA BLANCA UB 63/ 35/ 71/ 40/ 71 00000 .ELP...NONE 14 / BIRD N tx COASTAL BEND FORECAST DISCUSSION NATIONAL WEATHER SERVICE CORPUS CHRISTI TX 300 AM CST THU MAR 23 2000 BREEZY...CLOUDY...AND HUMID NIGHT ONCE AGAIN IN SOUTH TEXAS. WINDS HAVE REMAINED UP THIS MORNING...THANKS TO THE CONVECTION IN WEST TEXAS. EXPECT WINDS TO DIMINISH BEFORE SUNRISE...AS THE ATMOS DECOUPLES. UPPER LOW CURRENTLY OVER SOUTHERN NEW MEXICO WILL LIFT RAPIDLY NORTHEASTWARD TODAY. SQUALL LINE IN WEST TEXAS WILL PROPAGATE EAST THROUGH THE DAY. KDFX RADAR AND SAT IMAGES INDICATE THE LINE IS DEVELOPING SOUTHWARD AS IT MOVES EAST. RUC AND MESO ETA GUIDANCE INDICATE THE LINE WILL ENCOUNTER A STRONG CAP AT THE MID LEVELS IN OUR CWA. ALSO...DYNAMICS WILL SHIFT SIGNIFICANTLY NORTHWARD THROUGHT THE DAY...AND WILL NOT PROVIDE THE SUPPORT TO BREAK THE CAP DOWN. HOWEVER...THE LINE SHOULD PASS CLOSE TO THE NORTHERN COUNTIES...SO WILL INCLUDE LOW POPS FOR THIS AFTERNOON IN THE VCT AREA. WINDS WILL BE A PROBLEM FOR THROUGH AROUN 18Z IN THE AREA. SUFFICENT MORNING CLOUDS WILL MOSTLY LIKELY KEEP THE STRONG LLJ WINDS FROM MIXING DOWNWARD...AND THE APPROACH OF THE 850 MB TROF WILL WEAKEN THE GRADIENT THIS AFTERNOON. WITH THIS IN MIND...WILL BREAK ZONES INTO A THIS MORNING/THIS AFTERNOON GROUPING TO HIGHLIGHT BREEZY CONDINTIONS THIS MORNING. EXTENDED...LATEST MRF RUN INDICATES ANOTHER UPPER LOW WILL DIVE INTO THE SW US THIS WEEKEND. AS WITH THE CURRENT SYSTEM...LOW APPEARS TO LIFT OUT TOO FAR NORTH TO PROVIDE A SIGNIFICANT CHANCE OF RAINFALL. MARINE...WINDS DECREASING THROUGH THIS AFTERNOON. SCA FOR ALL AREAS THIS MORNING FOR WINDS IN THE BAYS AND SWELLS OFFSHORE. PRELIM NUMS.. CRP BB 083/064 083/066 083 200 LRD BB 087/062 088/066 080 100 VCT EB 082/061 082/065 080 310 JMC.84.SYN GW.86.MES .CRP...SCA GMZ230-235-250-255-270-275 tx SOUTH CENTRAL TEXAS FORECAST DISCUSSION NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX 230 AM CST THU MAR 23 2000 UPPER LOW IN SOUTHWEST NEW MEXICO APPEARS TO BE KICKING OUT TOWARD THE EAST NORTHEAST AS THE MODELS HAVE INDICATED. MAIN UPPER DYNAMICS WILL REMAIN NORTH OF FORECAST AREA BUT SURFACE CONVERGENCE LIKELY TO SPREAD CONVECTION EASTWARD ACROSS THE NORTHERN HALF OF AREA DURING THE DAY. FORECAST PROBLEM IS JUST HOW FAR SOUTH THE SOUTHERN END OF CONVECTION LINE WILL EXTEND AND PRECISE TIMING OF THE LINE. CONVECTION CURRENTLY IS LYING ALONG THE 567 1000-500MB THICKNESS LINE AND NEW 06Z RUC MOVES THAT LINE TO THE AUS AREA BY 18Z. THAT SEEMS REASONABLE. ETA PRECIP PATTERN IS NOT VERIFYING WELL AND AVN IS ALREADY TOO FAST ON EASTWARD MOVEMENT. 06Z RUC SEEMS TO HAVE THE BEST PRECIP PATTERN. ADJUSTING RUC PRECIP PATTERN TO CURRENT CONVECTION SHOWS THAT THE SOUTHERN END WILL BUILD ONLY SLIGHTLY FARTHER SOUTH AS IT MOVES EAST. SCATTERED LIGHTER SHOWERS OVER EASTERN COUNTIES ARE SPREADING NORTHWARD AHEAD OF THE STRONG CONVECTION. SURFACE NORTHWEST WINDS ARE QUITE STRONG BEHIND THE CONVECTION SO EXPECT THE DRY LINE TO SPREAD EASTWARD ACROSS THE AREA DURING THE DAY BUT WEAKEN WHILE DOING SO. MODELS HAVE BEEN CONSISTENT IN HALTING THE DRY LINE AND MOVING IT BACK WEST THURSDAY NIGHT AND FRIDAY AS UPPER LOW RETREATS NORTHEASTWARD. ALTHOUGH THE SURFACE MOISTURE LIKELY WILL MOVE BACK NORTHWESTWARD...ENOUGH DEEP LAYER DRYING WILL OCCUR TO KEEP RAIN CHANCES LOW AFTER TODAY. NEXT PRECIP SYSTEM DUE IN AREA AROUND MONDAY. PRELIMS AUS 8O/56/82/63 7001 SAT 83/60/82/65 5001 DRT 87/59/84/63 2001 .EWX...NONE. 16/03/20 tx AREA FORECAST DISCUSSION...CORRECTED FOR HEADER NATIONAL WEATHER SERVICE WILMINGTON NC ISSUED BY THE NATIONAL WEATHER SERVICE CHARLESTON SC 1007 AM EST THU MAR 23 2000 N TO NE WINDS 1O TO 20 KT AND GUSTY ALONG COAST EXPECTED TO CONTINUE THROUGH EARLY EVENING. LOW CLOUDS LIKELY TO REMAIN THROUGH MOST OF THE AFTERNOON WITH EROSION AND DISSIPATION OCCURRING PREDOMINANTLY FROM N TO S. 12Z RUC SHOWS SIG RH OVER CSTL SC AND W NC THROUGH THE AFTERNOON. CURRENT TEMPS LOOK ON TRACK SO NO SIG CHANGE TO CURRENT FCST. CWF...FPSN7 STILL REPORTING SUSTAINED WINDS OF 27 TO 34 KT PAST FEW HRS. STRONG SCA WILL BE MAINTAINED ACCORDING TO PREVIOUS FCST WHICH IS ON TRACK. WINDS SHOULD DIMINISH SLOWLY DURG THE AFTN AND SEAS SHOULD START TO SLOWLY SUBSIDE. .ILM...SMALL CRAFT ADVISORY SURF CITY NC TO SOUTH SANTEE RIVER SC. SLB/SR nc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON NC 1004 AM EST THU MAR 23 2000 N TO NE WINDS 1O TO 20 KT AND GUSTY ALONG COAST EXPECTED TO CONTINUE THROUGH EARLY EVENING. LOW CLOUDS LIKELY TO REMAIN THROUGH MOST OF THE AFTERNOON WITH EROSION AND DISSIPATION OCCURRING PREDOMINANTLY FROM N TO S. 12Z RUC SHOWS SIG RH OVER CSTL SC AND W NC THROUGH THE AFTERNOON. CURRENT TEMPS LOOK ON TRACK SO NO SIG CHANGE TO CURRENT FCST. CWF...FPSN7 STILL REPORTING SUSTAINED WINDS OF 27 TO 34 KT PAST FEW HRS. STRONG SCA WILL BE MAINTAINED ACCORDING TO PREVIOUS FCST WHICH IS ON TRACK. WINDS SHOULD DIMINISH SLOWLY DURG THE AFTN AND SEAS SHOULD START TO SLOWLY SUBSIDE. .ILM...SMALL CRAFT ADVISORY SURF CITY NC TO SOUTH SANTEE RIVER SC. SLB/SR nc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE COLUMBIA SC 1000 AM THU MAR 23 2000 LO LVL MSTR HAS SPRD OVR CWA. 06Z ETA SHOWING LOW LVL MSTR CONTG THRU THE DAY. CUR RUC IS A LTL FASTER WITH CLRG. ATTM WL OPT FOR ETA SOLN WITH CONTD CLDS DURG THE DAY. WRN EDGE OF CLDS HAVE MOVD LTL DURG THE PAST FEW HRS AND SM CLRG MAY OCCUR HERE LATR THIS AFTN. WL ADJUST FCST TO MOSTLY CLDY...BCMG PC LATE IN THE WEST. HIGHS 60/65. .CAE...NONE. CDL sc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MIDLAND/ODESSA TX 1011 AM CST THU MAR 23 2000 CONTEMPLATING CANCELING WIND ADVISORY ACROSS THE AREA. PER 12Z RUC...7H JET MAX IS E OF CWFA WITH A 2NDRY MAX S AROUND KFST...5H 90KT MAX IS EXITING INTO THE CONCHO VALLEY. THIS COMBINED WITH MARGINAL MSL GRADIENT AND POOR 85H-5H LR'S OF 3-5 C/KM SUGGEST MINIMAL ADVISORY CRITERIA AT BEST. WITH JAYTON PROFILER SHOWING THAT 7H WINDS MAY BE A LITTLE STRONGER THAT WHAT RUC IS DEPICTING AND WINDS SUSTAINED AT 27KT HERE AT KMAF WILL WAIT AT LITTLE LONGER BEFORE CANCELING. NONETHELESS CWFA WILL BE IN THE WINDY CATEGORY... DUST SHOULDN'T BE A PROBLEM PER MARGINAL WIND AND RAINS OF LATE. WSM PROFILER SHOWING WINDS VEERING AROUND SO PASS MAY NOT CATCH ALL OF THE WIND AND WE'LL PROBABLY HAVE ANOTHER MARGINAL WIND EVENT THERE. .MAF... TX...HIGH WIND WARNING TODAY FOR THE GUADALUPE MOUNTAINS OF WEST TEXAS...TXZ258. ...WIND ADVISORY TODAY FOR THE NORTHERN AND CENTRAL PERMIAN BASIN AND WESTERN LOW ROLLING PLAINS...TXZ045>048-050>053-058>063- 067>070. NM...HIGH WIND WARNING TODAY FOR THE GUADALUPE MOUNTAINS OF SOUTHEASTERN NEW MEXICO...NMZ027. ...WIND ADVISORY TODAY FOR SOUTHEASTERN NEW MEXICO...NMZ028-028- 033-034. GPM tx EAST CENTRAL FLORIDA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MELBOURNE FL 232 PM EST THU MAR 23 2000 SHORT TERM MODELS CONTINUE IN GENERAL AGREEMENT THROUGH H48 WITH RESPECT TO THE FLORIDA WEATHER PATTERN. THE MAIN QUESTION WILL ADDRESS THE MOISTURE POCKET HUGGING SE COAST FROM CAPE HATTERAS TO CAPE CANAVERAL. ALL OF THE SHORT TERM MODELS DEVELOP A SMALL H50 VORT MAX OVER SOUTH CAROLINA AND MOVE IT SOUTH AROUND THE BASE OF THE H50 TROF THROUGH 00Z SATURDAY. MOST OF THE MODELS KEEP THIS FEATURE OFFSHORE... BUT THE RUC DEVELOPS A WEAK SECONDARY VORT MAX OVER GEORGIA/ALABAMA AND MOVES IT ACROSS KJAX TONIGHT AHEAD OF THE MAIN VORT MAX. THIS COULD INDUCE IN A FEW LIGHT COASTAL SHOWERS...ESPECIALLY WITH AN ONSHORE FLOW UP TO H70. HOWEVER...UPPER SUPPORT FOR THIS FEATURE WILL BE ALMOST NON-EXISTENT. MAY INTRODUCE POPS FOR THE IMMEDIATE COASTAL REGIONS TONIGHT...BUT WILL KEEP THEM BELOW 20 PERCENT. OTHERWISE...A TEXTBOOK OMEGA BLOCKING PATTERN IN THE H85-H50 LAYER OVER THE SOUTHEAST WILL KEEP THE FORECAST HIGH AND DRY THROUGH SATURDAY. THE PATTERN WILL DAMPEN OUT THROUGH THE WEEKEND AS THE SHORTWAVE TROUGH OVER THE PLAINS RIDES OVER ITS TOP...BUT THIS WILL JUST SERVE TO PUSH THE RIDGE AXIS DIRECTLY ON TOP OF FLORIDA. COMBINATION OF DAYTIME CLOUDS AND AN ONSHORE FLOW WILL REDUCE DIURNAL TEMPERATURE FLUXES...WITH HIGHS NEAR CLIMO...AND LOWS AT OR ABOVE CLIMO. EXTENDED...SEE LITTLE NEED TO CHANGE THE CURRENT FORECAST. MRF INDICATES THE NEXT FRONT WILL MOVE THROUGH THE EASTERN U.S. AROUND 12Z SUN AND OFF THE FLORIDA COAST BY 12Z MONDAY. HOWEVER...AS IT DOES...IT DECOUPLES THE SOUTH PORTION OF THE FRONT FROM THE NORTH WHILE GIVING IT LIMITED MOISTURE TO START WITH. A 90 KNOT H25 JET MAX IS INDICATED OVER THE PENINSULA BY 00Z MONDAY AND COULD ENHANCE THE ENVIRONMENT TO ALLOW A FEW SHOWERS...BUT CONFIDENCE IS TOO LOW TO INTRODUCE POPS AT THIS TIME. MARINE...BUOYS CONTINUE TO INDICATE WINDS AND SEAS ABOVE SMALL CRAFT ADVISORY LEVELS. THE WINDS WILL RELAX OVERNIGHT AS THE TROUGH OVER THE SOUTHWEST ATLANTIC PUSHES SOUTH...BUT SEAS WILL TAKE A LITTLE BIT LONGER TO SUBSIDE AS SWELLS GENERATED BY THE LONG NORTH-NORTHEAST FETCH CONTINUE TO MOVE DOWN THE EAST COAST. SEAS WILL DECREASE FROM NORTH TO SOUTH THROUGH SUNDAY AS THE SURFACE HIGH PRESSURE RIDGE DRIFTS ACROSS THE FLORIDA PENINSULA. WILL MAINTAIN SMALL CRAFT ADVISORY THROUGH TONIGHT. PRELIMINARY CCF NUMBERS... DAB BB 060/075 058/077 057 81100 MCO BB 058/079 057/080 058 81000 MLB BB 063/077 064/078 062 81100 .MLB...SMALL CRAFT ADVISORY FLAGLER BEACH TO JUPITER INLET. AVIATION/FIRE WX...TROUTMAN PUBLIC/MARINE......BRAGAW fl AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO 254 PM CST THU MAR 23 2000 VIS LOOP THRU 1955 UTC SHWS LO/MID CLD DECK WRAPPED ARND UPR LO OVR SW OK. LEADING EDG OF CLDS OVERSPREADING WRN CWA BUT E RMNS MAINLY CLR WITH TEMPS IN 70 DEG NEIGHBORHOOD. DUE TO STG LWR TROPOSPHERIC RDG OVR ERN U.S. DRIER MID 40S DEW PTS BEING ADVTD INTO FCST AREA BY WAY OF SE BNDRY LYR GRADIENT. HOWEVER MODELS FCST INSTABILITY AXIS TO SWEEP ACR CWA LTR TNGT AS 50 DEG SFC DEW PTS GET DISPLACED OVR FCST AREA AHD OF LIFTING SW LO. RUC INDICATES RAPID DESTABILIZATION ARND 0600 UTC WITH -3 LI'S AND 700-500 HPA DELTA T'S IN 20-23 DEG C RANGE OVR WRN CWA. WITH DECENT DRY LN TRAILING INSTABILITY AXIS OVR SRN PLNS THIS SHLD PROVIDE LO LVL SPARK TO IGNITE CNVTN LTR THIS EVNG. WITH MOST LIFTING DRY LNS THUS FAR THIS SEASON THE MID/UPR SHEAR HAS OUTRUN SO-CALLED DRY LN. HOWEVER INGREDIENTS APPR TO BE MORE IN PHASE WITH ANTICIPATED EVENT TNGT. WILL NOT INSERT IN FCST BUT COULD PSBLY SEE ISOLATED GUSTY WNDS AND AT LEAST SMALL HAIL LTR TNGT. DUE TO XPTD NATURE OF EVENT NOW LOOKING MORE LIKE BKN LN OF CNVTN WILL CUT DOWN ON CRNT QPF FCST. WILL STAY WITH CATEGORICAL MENTION OF PCPN AND ADJUST WORDING TO ACCOUNT FOR TIMING NAMELY LATE TNGT OVR ERN ZNS. WILL NOT DEVIATE FM CRNT TEMP AND GUIDANCE FCST. MODELS FCST AXIS OF 500-100 HPA POT VORTICITY THRU SW CWA BY 1200 UTC AND THRU NE ZNS BY 1500 UTC. WILL THEREFORE REMOVE POPS FOR FRI AM IN W AND LEAVE CHC POP ERLY FRI E. WITH DECENT SUBSIDENCE AND MIXING OF STRATOSPHERIC AIR OVR RGN FRI THINK TEMPS SHLD EXCEED GUIDANCE IN MOST LOCATIONS. CRNT FCST REFLECTS THIS SO WILL NOT MAKE SGFNT CHGS. DECENT WKEND SHAPING UP WITH MAX TEMPS WELL INTO 60S AND DRY CONDS XPTD. LATER HALF OF XTND FCSTLKS INTERESTING. MRF ONCE AGN SUGGESTING DEEP CLOSED LO MVG ACR SRN PLNS WITH SEF CAN SHOWING DEEP ERN U.S. TROF THEREFORE SLOWER AND FTRH S MVMNT OF NXT SW LO. WILL KEEP DRY FCST INTACT ON MON THEN INTRODUCE CHC FOR PCPN TUE/WED. .EAX...NONE. BODNER mo NORTHERN GREAT BASIN FORECAST DISCUSSION NATIONAL WEATHER SERVICE ELKO NV 200 PM PST THU MAR 23 2000 SYNOPSIS...WEAK HIGH PRESSURE WILL BUILD INTO NEVADA TONIGHT AND FRIDAY. A PACIFIC STORM WILL DROP SOUTH ALONG THE CALIFORNIA COAST THIS WEEKEND...BRINGING A THREAT OF SHOWERS TO THE GREAT BASIN. THE MAIN STORM ENERGY AND COLDER AIR WILL TRACK SOUTH THROUGH ARIZONA SUNDAY AND MONDAY. ANOTHER PACIFIC WEATHER SYSTEM WILL REACH THE GREAT BASIN TUESDAY. SHORT TERM...TROF MOVING EAST OF STATE AT TIME WITH SHWRS ENDING. COULD BE A FEW SHOWERS LINGERING OVER HIGHER TERRAIN OF CENTRAL NV ALONG OLD BAROCLINIC ZONE. WEAK S/WV TROF APPROACHING CALIF COAST IS BEST CAPTURED BY AVN AND RUC. THERMAL PRES TROF DRIFTS EAST INTO NE NV BY FRI EVE AND SERVES AS INSTABILITY AXIS. ETA LOOKS OVERDONE WITH LOW LIFTED INDICES FRI AFTERNOON AND PREFER LESS CONVECTIVE AVN. STILL ENOUGH INSTABILITY TO TRIGGER ISOLD CONVECTION FRI AFTERNOON. NEXT SYSTEM IN GULF OF ALASKA WILL DIG SOUTH ALONG CALIF COAST AND SLIGHTLY FURTHER WEST PER NEW AVN. WATER VAPOR SATELLITE SHOWS GOOD RIDGING BEHIND THIS FEATURE IN GULF AND DIGGING IS SUPPORTED BY SPLIT FLOW AND LONG WAVE PATTERN. WITH COLD AIR AND DYNAMICS LAGGING BACK OVER CALIF...GREAT BASIN WILL JUST SEE THREAT OF AFTERNOON CONVECTION AGAIN SATURDAY WITH NO MAJOR SYSTEM. THETA E RIDGE SUPPORTS CONVECTIVE AXIS OVER EXTREME NRN NV LATE SAT. LONG TERM...ENSEMBLE SOLUTION NOT TOO FAR FROM MRF WITH CUT OFF OVER DESERT SW GETTING KICKED OUT BY NEXT S/WV MON. NOGAPS LOOKS WRONG HOLDING LOW OFFSHORE SO LONG WITH NEXT UPSTREAM S/WV ON THE MOVE. SYSTEM ON TUE LOOKS MORE LIKELY TO PRODUCE SIG WEATHER FOR GREAT BASIN AS SUPPORTED BY ENSEMBLE AND MRF. SYSTEM WILL LIKELY CUT OFF FURTHER NORTH THAN THE WEEKEND SYSTEM. KBB .EKO...NONE. nv