EAST CENTRAL FLORIDA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MELBOURNE FL 925 AM EDT WED APR 5 2000 CURRENTLY...GUSTY NORTHWEST TO NORTH FLOW RESULTING IN BRISK CONDITIONS. WIND CHILLS RANGED FROM THE MID 30S TO THE LOWER 40S AROUND SUNRISE. CANAVERAL PROFILER AND AREA WINDS AT 2000 FEET WERE AROUND 25 KNOTS. AS A RESULT OF THIS...WINDS WERE RUNNING ABOVE THOSE IN THE FORECAST. SCATTERED CLOUDS WERE ALONG AND EAST OF THE GULF STREAM AND MOVING DUE SOUTH. TODAY...LATEST RUC FOLLOWS TREND OF THE OTHER SHORT RANGE MODELS IN WEAKENING THE PRESSURE GRADIENT/WINDS THIS AFTERNOON. UNTIL THEN THOUGH...EXPECT IT WILL BE BREEZY SO PLAN TO ADD THIS TO THE FORECAST. A FEW CLOUDS EXPECTED TO PUSH TO SOUTHERN COASTAL SECTIONS AS FLOW VEERS SLIGHTLY TO THE NORTH NORTHEAST...BUT THE EXTREMELY DRY AIR MASS SHOULD EVAPORATE THEM AND KEEP IT A CLOUD FREE DAY OVER LAND AREAS. FIRE WEATHER...RED FLAG CONDITIONS LIKELY TO BE MET BY AFTERNOON ACROSS MOST OF THE AREA DUE TO LOW RH DURATIONS...AND WIND. ONLY EXCEPTION MAY BE ALONG IMMEDIATE COAST AS NNE WIND COMPONENT DEVELOPS AND KEEPS DEWPOINTS SOMEWHAT ELEVATED...BUT WILL KEEP RED FLAG GOING ALL ZONES. ON THU...MODIFICATION OF DRY AIRMASS WILL BE SLOW TO OCCUR...ESPECIALLY OVER NORTHERN AND INTERIOR SECTIONS...IN CLOSER PROXIMITY TO RIDGE AXIS. WILL THEREFORE ISSUE FIRE WEATHER WATCH FOR THU AFTERNOON THOSE AREAS. MARINE...BUOY WAS OVER 20 KNOTS AND SEAS WERE ABOVE ADVISORY THRESHOLD. NORTH TRAJECTORY/COLD ADVECTION SHOULD KEEP SEAS 7 FEET OR ABOVE...EVEN AS GRADIENT SLACKENS DURING THE AFTERNOON. .MLB...SCA FLAGLER BEACH TO JUPITER INLET. RED FLAG WARNING FOR EAST CENTRAL FLORIDA THIS AFTERNOON. FIRE WEATHER WATCH THURSDAY...LAKE...ORANGE...SEMINOLE OSCEOLA...OKEECHOBEE...VOLUSIA AVIATION/FIRE WX...KELLY PUBLIC/MARINE......LASCODY fl SOUTHWEST IDAHO/SOUTHEAST OREGON AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BOISE IDAHO 300 PM MDT WED APR 05 2000 IN SHORT RANGE LATEST RUC ALIGNS WELL WITH SHORT WAVE AND CLDS OVER NW WITH AC/CI THRU BKE CO AND ENTERING W-CENTRAL MTNS...NRN HARNEY AND MALHEUR COUNTIES FOR THIS EVENING. MESOETA AND AVN PREFERRED IN SHORT RANGE IN TAKING A SOMEWHAT MOIST /CHC POPS N AND SLIGHT CHC S/ BUT LOW AMPLITUDE SYSTEM THROUGH REGION. NGM TOO DRY AND TOO COOL ESPECIALLY TOO COOL FRIDAY WITH FULL SPRING SUNSHINE. THICKNESS COOLING CONCENTRATED N AND CD FROPA MAINLY TIGHTENS GRADIENT OVER BOISE CWFA. BREEZY LOOKS GOOD ONTARIO-MOUNTAIN HOME AT LEAST FOR THURSDAY AFTERNOON BECAUSE WITH TREASURE VALLEY ORIENTED NW-SE...NW JET ALIGNMENT WITH STRONGER WINDS ALOFT TO MIX DOWN FOR BREEZY CONDITIONS. SLIGHT CHC POPS FOR THURSDAY NIGHT SE ZONES THEN RIDGE COMES IN WITH WARMING THICKNESSES AND WARMING LOW ALT TEMPS ESPECIALLY SW PART OF CWA...FOR FRIDAY. SIMILAR TEMPS THU/FRI FOR TWF CO. PREFER UKMET OVERALL WHICH MEANS A CHANGE TO INCREASING CLOUDS SE OREGON SATURDAY AND MUCH OF SW IDAHO FOR SATURDAY. AND GIVES A CHANCE OF SHOWERS OR RW/TRW SRN IDAHO MTNS EACH SUNDAY AND MONDAY. PREFER FARTHER S TRACK OF ECMWF AND NOGAPS OVER MRF...AND PREFER LOWER AMPLITUDE/FASTER EC OVER NOGAPS BECAUSE UPPER LOW IS EJECTING INTO LONGWAVE U.S./CANADIAN W COAST RIDGE. FMR MIGHT BE TOO WARM ON MAXES SUN/MON BUT THEY DO HAVE CHC POPS COVERED. .BOI...NONE. id AREA FORECAST DISCUSSION...UPDATE NATIONAL WEATHER SERVICE DES MOINES IA 925 AM CDT WED APR 5 2000 SHORT TERM... WILL BE UPDATING TO WARM TEMPS TO NEAR RECORD LEVELS THIS AFTERNOON. OAX SOUNDING IMPRESSIVE WITH 20C AT 850 MB, AND DRY ADIABATIC LAPSE RATES EXPECTED THROUGH THE SURFACE LAYER BY 21Z. ALREADY DRY ADIABATIC IN MID LEVELS. WILL GO WITH 80-85 SW CWA AND LOWER 80S SE. UPPER 70S FURTHER N. RECORDS AT DSM AND ALO AT 84 DEGREES. AS FAR AS OUR WIND ADVISORY, IT'S LOOKING GOOD AT THIS POINT. 700-500MB SPEED MAXES IS MOVING THROUGH SD ALONG WITH SOME DARKENING LAST COUPLE HOURS ON WATER VAPOR IMAGERY IN NE. GUSTS OVER 50KT IN RESPONSE AT RAP AND POINTS BEYOND WITHIN THE ISALLOBARIC RISE MAX. RUC FORECASTS SHOW THE RISE/FALL COUPLET TRANSLATING INTO NW IA. NLG PROFILER ALSO SHOWING 50KT AT THE 500 M AGL GATE. .DSM...WIND ADVISORY NORTHWESTERN THIRD OF CWA THIS AFTERNOON AND EVENING. IAZ004>007-015>017-023>026-033>036-044-045- KULA ia AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GAYLORD MI 1036 PM EDT WED APR 5 2000 CURRENT REGIONAL SFC ANALYSIS SHOWS LOW CENTER OVER FAR NC MN...WITH TROUGH EXTENDING SSE THROUGH CENTRAL WI. LATEST IR LOOPS SHOW NARROW RIBBON OF WARM ADVECTION MID AND UPPER LEVEL CLOUD COVER CURRENTLY MOVING THROUGH THE REGION...WITH SFC WARM FRONT ON BACK EDGE OF THESE ENHANCED CLOUDS. HOWEVER...AS PER KAPX 00Z OBSERVED SOUNDING...THE AIRMASS BELOW 700 MB WAS QUITE DRY INITIALLY. BY THE TIME THE LOW LEVELS COULD SUFFICIENTLY MOISTEN FOR PRECIP TO REACH THE GROUND...THIS NARROW REGION OF ISENTROPIC ASCENT/DEEPER MID LEVEL MOISTURE AND ICE SEEDING WOULD HAVE PUSHED NORTHWARD. AS A RESULT...UP TO THIS POINT MOST LOCATIONS HAVE REPORTED ONLY A BRIEF PERIOD OF RAIN SHOWERS OR SPRINKLES...SOME OF WHICH COULD BE MIXING WITH OR CHANGE TO SNOW/SLEET IN FAR NRN LWR AND (ESPECIALLY) IN ERN UPR MI GIVEN THE LOWER BOUNDARY LEVEL TEMPS ALONG WITH THE EVAPORATIVE COOLING POTENTIAL. IN FACT...THE 00Z KAPX RAOB SHOWS WETBULB TEMPS BELOW ZERO IN ALL BUT THE LOWEST 500 OR SO FEET ABOVE THE GROUND. MAIN FORECAST CONCERN FOR THE REST OF THE NIGHT IS WITH ADDITIONAL PRECIP CHANCES/COVERAGE. LATEST WATER VAPOR IMAGERY SHOWS DEFINITIVE DRY-SLOTTING ON THE HEELS OF THIS WARM FRONTAL BAND OF ENHANCED CLOUDS/PRECIP. ACCORDING TO THE LATEST MODEL FORECAST SOUNDINGS... THIS WILL STRIP MOISTURE ABOVE THE -10C ISOTHERM ACROSS MUCH OF NRN LWR (WITH PERHAPS THE FAR NRN PORTION THE EXCEPTION)...LIMITING THE ICE NUCLEATION AND (THUS) CHANCES FOR ANYTHING MORE THAN DRIZZLE. HAVE WORDED THIS ACCORDINGLY IN AREAS ALONG/SOUTH OF M-32 WITH THE LAST UPDATED FORECAST. GIVEN THE GREATER DYNAMICAL SUPPORT (DPVA/LFQ JET FORCING) AND THUS DEEPER MOISTURE...HAVE CONTINUED TO HIT POPS/MEASURABLE PRECIP HARDEST ACROSS ERN UPR MI ALONG AND NORTH OF THE EXPECTED SFC LOW TRACK. THE PROBLEM THEN BECOMES PRECIP TYPE...AGAIN GIVEN THE DEEP LAYER OF SUB FREEZING WETBULB TEMPS AS PER 00Z RAOBS. LATEST (00Z) RUC FCST SOUNDINGS IN FACT NOW SUPPORT MORE SNOW THAN RAIN ACROSS ERN UPR OVERNIGHT...WITH THE COOLING DUE TO EVAPORATION AND MELTING EFFECTS APPEARING TO OFFSET THE WARM ADVECTION SOMEWHAT. THEREFORE...WILL LIKELY UPDATE THE FORECAST IN THE ERN UPR MI ZONES. HAD LOWERED THE WINDS DOWN A BIT FOR THE OVERNIGHT (FROM THE 20- 30 MPH IN THE PRIOR FCST). EVAPORATIVE COOLING HAS STABILIZED THE LOW LEVELS A BIT...ALLOWING SFC WINDS TO DECOUPLE SOMEWHAT (EVEN SOUTH OF THE WARM FRONT...WHERE WINDS REMAIN PREDOMINANTLY SE OR CROSS-ISOBARIC). .APX...NONE. HURLEY mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 525 PM EDT WED APR 5 2000 FCST CONCERNS DEAL WITH EFFECTS OF SHIFTING LOW PRESSURE IN REGARD TO HIGH WIND POSSIBILITIES AND -SHRA/-SHSN TONIGHT. 20Z SFC ANALYSIS SHOWS LOW PRESSURE OVR NWRN MN BEGINNING TO MOVE SOUTHEAST ATTM. AHEAD OF LOW IN AREA OF STRONG ISENTROPIC ASCENT AT 290K...AREA OF WIDESPREAD LGT RA AND LGT SN EXISTS OVER NRN MN INTO SRN ONTARIO AND MANITOBA. BIGGEST STORY THIS AFTN ARE WINDS OVR NRN PLAINS AS WINDS HAVE GUSTED AS HIGH AS 55 KTS OVR PARTS OF THE DAKOTAS. TONIGHT...AS LOW DIVES SOUTHEAST ARRIVING OVR ERN UPR MI BY 12Z PER 18Z ETA...LGT RAIN WL OVR SPREAD AREA. 88D RETURNS STRETCHING INTO WRN UPR MI ALTHOUGH SFC OBS POINT TO PRECIP ONLY BEGINNING TO REACH GROUND IN IWD WITH 7SM VSBY. AS UPR MI STAYS IN WAD THRU EVENING HRS PRECIP TYPE WL STAY LIQUID. FCST SOUNDING ALSO SHOW ABOVE FREEZING LAYER STAYING ABOVE H8 THROUGH 06Z. ONLY EXCEPTION IS IN ERN UPR MI WHERE COLD AIR AT H8 HAS HUNG ON THROUGHOUT DAY AS LATEST RUC SHOWS H8 TEMPS AOB ZERO OVER EXTREME ERN UPR MI THRU 03Z. RESULT IS PRECIP AS A RA/SN MIX THROUGHOUT NIGHTTIME HRS. IN WRN UPR MI...18Z ETA PROGS H8 TEMPS TO DROP BELOW ZERO C BY 09Z OVR KEWEENAW...AND BY 12Z OVR CENTRAL UPR MI. IN THOSE AREAS WENT WITH RAIN...POSSIBLY MIXING WITH SN OVR HIGHER TERRAIN LATE. AS FOR THE WINDS...HAVE BACKED DOWN FM YESTERDAYS FCST MAINLY DUE TO LOW PASSING ALMOST DIRECTLY OVER THE FA. AS OF NOW IT APPEARS THE BEST WIND WL REMAIN TO THE SOUTH OF THE FA AS THAT IS WHERE THE BEST DECENT BEHIND SHRTWV WL REMAIN. ONLY COUNTY WITH CHANCE OF SEEING VRY STRONG WINDS WL BE GOGEBIC COUNTY AS THEY WL BE RIGHT ON FRINGE OF THE STRONG WIND CORE AT H9 AROUND 40KT...WORKING AGAINST FCST GUSTS TO 45 KT WL OF COURSE BE TIME OF DAY. THURSDAY...AS LOW RAPIDLY PULLS EAST...NEAR GEORGIAN BAY BY 18Z PER 18Z ETA. PRECIP WL QUICKLY TAPER OFF AS BEST FORCING EVADES THE FA. WINDS SHOULD ALSO DIE DOWN...ESPECIALLY WEST AS SFC RIDGE BEGINS TO BUILD IN FM WEST. IN ERN UPR MI CAA COMBINED WITH CLOSE PROXIMITY TO VORT DECENT AREA SHOULD CONTINUE GUSTY WINDS UNTIL AFTERNOON. NEXT STORM OF MENTION HAS ALSO TRENDED AWAY FM A MAJOR WX PRODUCER WITH LATEST MRF...AVN...AND UKMET RUNS (EUROPEAN UNAVAILABLE). ALL MODELS DIG VORT MAX MORE AND ONLY SKIRT ERN UPR MI WITH H8-H5 QVECTOR CONVERGENCE AND H7 OMEGA BY 18Z FRI PER AVN. RESULT IS PULLING BACK ON CATEGORICAL WORDING TO CHANCE...BEST OVR ERN UPR MI. .MQT...NONE. JLA mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 1040 AM EDT WED APR 5 2000 GOES-8 WV LOOP SHOWING VIGOROUS UPR LVL SHRTWV TROF MOVG ACROSS NO DAK 11-14Z EVIDENT BY IMPRESSIVE CYCLONIC SWIRL IN IMAGERY. RUC AND OTHER SHRT TERM MODELS PROGGING THIS SHRTWV TO AMPLIFY AS IT DRIVES ESE TWRD THE UPR GRTLKS THIS AFTN/TNGT. STRONG DIFF PVA NOTED AHEAD OF TROF PER H7-H4 AND H5-H3 Q-VECTOR CONVERGENCE PLOTS WITH STRONG DIFF DIVERGENCE ALOFT AIDED BY LOW LVL CONVERGENCE AT NORTHERN TERMINUS OF INTENSIFYING 45-50 KT LOW LVL JET AS IT SHIFTS EAST TWRD WRN UPR MI LATE THIS AFTN. ADDITIONAL ASCENT WILL BE FORCED BY AGEO CIRCULATION ASSCTD WITH RIGHT ENTRANCE REGION OF 80 KT 500 MB JET STREAK PROGD TO RACE INTO CNTRL WIS BY 00Z THIS EVNG. WITH MODERATE LOW LVL WAA AHEAD OF THE UPR LVL TROF AND SLGT COOLING ALOFT... MID LVL LAPSE RATES WILL STEEPEN THIS AFTN ENHANCING MID LVL INSTABILITY. GIVEN SIGNIFICANT INTENSITY OF THE DYNAMICS ASSOCIATED WITH THIS TROF... COMBINED WITH IMPRESSIVE JET ENERGY AND WAA/ISENT LIFT AHEAD OF APRCHNG SFC LOW... AND STEEPENING MID LVL LAPSE RATES... WILL INCLUDE MENTION OF THUNDERSTORMS IN LATE AFTERNOON AND EARLY EVENING PORTION OF THE FCST FOR THE WEST HALF OF UPR MI. PRIMARY LIMITING FACTOR WILL BE MOISTURE AS SFC AND H85 DWPTS REMAIN BONE DRY IN THE 36-40 F RANGE AND ARND 0 C RESPECTIVELY. CURRENT LIGHTING PLOTS AND SFC REPORTS INDICATE THUNDER AHEAD OF THE UPR LVL TROF OVER XTREME SE MANITOBA AND SW ONTARIO 11Z-14Z. AND THE STRONGEST DIFF PVA HAS YET TO AFFECT THIS REGION OF CONVECTION. OTHER MAJOR CONCERN FOR AFTN UPDATE IS PRECIP TYPE. 12Z INL SOUNDING SHOWING ABV FREZ LYR XTNDNG SFC THRU 800 MB... WITH MAX TEMP IN THE WARM LAYER ARND 3 DEG C THROUGH A CONSIDERABLE DEPTH. THIS LAYER VRY DRY HWVR WITH WET BULB BLO FREZ. ANY SIGN PRECIP WOULD EXPERIENCE ENOUGH EVAP COOLING TO CHANGE OVER TO ALL FROZEN PRECIP. HENCE WILL CONTINUE MENTION OF MIXTURE. XPECT MAJORITY OF PRECIP TO BE OF LIGHT ENOUGH INTENSITY HWVR TO REMAIN RAIN. GIVEN LOW FREZ LVL XPECT SLEET WITH MORE INTENSE SHWRS/THUNDER SHWRS. WITH CONTINUED WAA THRU THE AFTN XPECT CHCS FOR FROZEN PRECIP TO GRAD DIMINISH AS WARMER LAYER EXTENDS TO A GREATER DEPTH AND LOW-MID LVLS GRADUALLY MOISTEN. WITH TIGHTENING SFC GRADIENT AHEAD OF 986 SFC LOW XPECT WINDS TO PICK UP FAIRLY RAPIDLY THIS AFTN. WILL CONTINUE CURRENT WIND TRENDS IN ZONES. WITH GOOD MIXING XPECT TEMPS TO JUMP UP WITH INCREASED WAA. EXCEPTION WILL BE SE ZONES ALONG LK MI WHERE CHILLY SE WIND OFF LAKE WILL HOLD TEMPS DOWN. .MQT...GALE WARNING LAKE SUPERIOR. ED F mi FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND 815 PM CDT WED APR 5 2000 FCST CHALLENGE TONIGHT...WIND AND NEED FOR CONTINUED HEADLINES. 987MB LOW JUST EAST OF BDE AT 01Z WITH STRONG PRESSURE RISES OVER ERN ND. VWP FROM KMVX SHOWS 45 KTS AT LOWEST GATE...DOWN FROM 55 KTS AROUND 23Z-00Z...WHEN STRONGEST WINDS HIT. ALL BUT FARGO DOWN TO BLO HIGH WIND WARNING CRITERIA. RUC HAS 55KT 85H WINDS AT 02Z BUT DECREASES THEM TO 40 KTS BY 06Z. THIS COMBINED WITH THE SETTING SUN WILL MEAN LESS MIXING AND LESS ADIABATIC SOUNDING. THUS FEEL COMFORTABLE IN LETTING HIGH WIND WARNING EXPIRE ON SCHEDULE AT 0215 UTC (915 PM CDT). HOWEVER...WINDS WILL STILL BE IN THE ADVISORY CRITERIA LEVELS MUCH OF THE NIGHT WITH A SLOW DECREASE IN WINDS FROM WEST TO EAST OVERNIGHT. WILL KEEP ADVISORY UP AT DVL UNTIL MIDNIGHT...AND ACROSS THE VALLEY AND NW MN ALL NIGHT. FAR NE ZONES (BDE) TO HAVE LESS WIND...BUT STILL FEEL PRESSURE GRADIENT TIGHT ENOUGH FOR ADVISORY THERE OVERNIGHT AS WE HAVE SEEN G30+KT AT WINNIPEG PAST FEW HOURS. AS FOR CLDS/PCPN...VARIOUS 12Z MODELS...18Z MESO ETA AND 00Z RUC ALL SHOW CLEARING FROM WEST TO EAST OVERNIGHT...REACHING FAR ERN CWFA AROUND 12Z. SCT RA/SN WILL CONTINUE TO MOVE EAST...WITH BACKEDGE OF THE WRAPAROUND SHOWERS SHOWN FROM KMVX AND CANADIAN RADARS FROM JUST WEST OF WINNIPEG TO FARGO. THUS WILL CONTINUE WITH RA/SN IN NW MN OVERNIGHT AND END PCPN IN ERN ND. WILL CHECK OVER OBS AT 9 PM AND HOIST UPDATE AND NEW NPW AROUND 915 PM. WILL UPDATE BOTTOM CODING INFO AFTER 9 PM AS WELL. .FGF...HIGH WIND WARNING ALL OF ERN ND AND PORTIONS OF NW AND WCNTRL MN ALG AND SOUTH OF HWY 2 UNTIL 915 PM CDT. WIND ADVISORY REMAINDER OF TONIGHT ALL ZONES. RIDDLE nd EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION NATIONAL WEATHER SERVICE TULSA OK 848 PM CDT WED APR 5 2000 00Z RUC KEEPS BOUNDARY NORTH OF THE AREA THRU 12 Z...BUT WINDS SHOULD DECREASE AS GRADIENT DECREASES WITH APPROACH OF SFC TROUGH. S WINDS WILL LIKELY REMAIN IN 10 TO 20 MPH RANGE IN THE S AND E ZONES BUT SHOULD BE LESS GUSTY THE REST OF THE NIGHT. CANCELLED LAST 2 HRS OF WIND ADVSY AND UPDATED ZONES WITH ONLY CHANGES TO WINDS AND RAISED MAXES A FEW DEGS IN SOME SRN ZONES. FCSTID = 13 .TUL... AR...NONE. OK...NONE. ok AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NORMAN OK 1023 AM CDT WED APR 5 2000 MAIN CONCERN THIS AFTERNOON IS STRONG WINDS AND HIGH TEMPERATURES. 12Z OUN SOUNDING SUPPORTS A HIGH TEMPERATURE OF 91 ASSUMING A MIXED LAYER OF 850 MB WHICH SHOULD BE REACHED BY EARLY TO MID AFTERNOON. 12Z UPPER AIR ANALYSES ALSO SUGGESTS 12 HOUR PROGS FROM LAST NIGHTS' MODELS VERIFIED WELL REGARDING 850-700 MB TEMPERATURES AND WINDS. RECENT RUC GUIDANCE IS ALSO ON TRACK. ONLY MAJOR CONCERN IS VICI PROFILER WHICH SHOWS 45 KNOTS JUST ABOVE THE SURFACE AND IS ABOUT 10 KNOTS STRONGER THAN RECENT MODEL GUIDANCE. STRONGER DOWNSLOPE FLOW ...THUS WARMER TEMPERATURES AND SLIGHTLY STRONGER SURFACE WINDS MAY RESULT. WILL NEED TO MONITOR FOR WIND ADVISORY BUT UNLESS OTHER PROFILERS SHOW STRONGER WINDS WILL LEAN AGAINST IT. FOR NOW WILL ONLY RAISE HIGH TEMPERATURES SLIGHTLY SOME AREAS. EXPECT A COLD FRONT ACROSS THE NORTHERN PLAINS TO CONTINUE SOUTHWARD THIS AFTERNOON REACHING NORTHERN KANSAS BY 00Z. PRE-FRONTAL TROUGH LIKELY TO REMAIN AHEAD OF IT WITH LAST NIGHT'S ETA/RECENT RUC SUGGESTING CONSIDERABLE BAGGINESS OCCURRING IN THE PRESSURE FIELD LATE IN THE DAY ACROSS NORTHWEST OKLAHOMA. WILL MENTION DECREASING WINDS LATE IN THE DAY ACROSS NORTHWEST OKLAHOMA FOR THIS REASON. ...WILL CONTINUE TO MONITOR FOR WIND ADVISORY. .OUN... OK...NONE. TX...NONE. JAMES ok AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MORRISTOWN TN 920 PM EDT WED APR 5 2000 THE CHILL IS GONE...AS THE SOUTHWEST GRADIENT CONTINUES TO TIGHTEN AND PRODUCE STRONG WARM AIR ADVECTION (ESPECIALLY 850 MB LEVEL WHERE LATEST RUC MODEL WARMS TEMPS TO 12 DEGS C OVER SE TN AND INCREASES WINDS TO NEAR 50 KTS BY 09Z THU). THE SURFACE WINDS APPEAR TO HAVE SETTLED IN AT SPEEDS OF 5-10 MPH THIS EVENING OVER THE VALLEY SPOTS...AND IT IS DIFFICULT TO ASCERTAIN EXACTLY WHAT THE SPEEDS ARE IN THE HIGHER TERRAIN GIVEN ABSENCE OF TOWER DATA. LIGHTEST WINDS ARE NOTED IN EXTREME NE TN AND MUCH OF SWRN VA ZONES...AND OF COURSE THIS FINDS COOLEST MIN TEMPS/DEWPTS ATTM. DIFFICULT TO DECIDE WHAT TWEAKS...IF ANY...ARE REQUIRED WITH MIN TEMP FORECAST. CHA/CSV/TYS MINS ARE RIGHT IN LINE WITH FWC MOS...WHILE TRI WAS ALREADY 7 DEGS BELOW FWC AT 06/00Z. FOR WIND FORECAST...IN SPITE OF INCREASING 850 MB WINDS OVERNIGHT... DOUBTFUL IF SPEEDS OVER 20 MPH WOULD MIX DOWN EXCEPT FOR HIGHEST PEAKS OF MTN ZONES. CURRENT WIND FORECAST LOOKS FINE..AS DOES SKY CONDITION. WILL CHECK TEMPS AGAIN AT 10 PM AND DETERMINE IF UPDATES ARE NEEDED. .MRX... NC...NONE. TN...NONE. VA...NONE. TG tn AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BURLINGTON VT 948 PM EDT WED APR 5 2000 SFC HI PRESS RIDGE (AND WK RIDGE ALOFT) TO CREST ACRS THE FA OVRNITE TONITE AS A STORM SYS MOVES ACRS THE GREAT LKS REGION. THIS STORM TO RIDE ACRS NY STATE AND NEW ENG ON THU. 21Z RUC SHOWS W-SW SFC FLOW DIMINISHING OVRNITE WITH SFC TEMPS GETTING DOWN INTO THE 20S BY 09Z. H85 MOISTURE TO START TO DRY OUT AFTER 06Z TONITE...WITH LOWER LYRS NOT DRYING OUT AT ALL. RUC CONTINUES TO CRANK OUT LT PCPN IN THE NE KINGDOM THRU 09Z. MID-LVL MOISTURE TO MOVE INTO WESTERN NY STATE AFTER 06Z AS WELL. H85 WAA TO INCREASE (ALONG WITH MORE LOW-LVL MOISTURE ASSOCIATED WITH THE GREAT LKS SYS) ACRS THE FA THRU 18Z THU. GOOD H85 MOISTURE ADVECTION TO AFFECT NORTHERN NY STATE AND SRN VT BY 12Z THU. H85 TEMPS STAY NEGATIVE ACRS MUCH OF THE FA THRU 18Z THU. H5 VORT MAX TO MOVE ACRS THE GREAT LKS REGION TONITE AND ACRS THE FA ON THU. FEEL THAT ANY PCPN ON THU WILL BE A SNOW TO RAIN SITUATION...SO REMOVED ANY MENTION OF FZRA IN THE ST LAW VLY FOR THU. BEST CHC FOR ANY FZRA THERE WOULD BE IF A GOOD NE FLOW DEVELOPS...AND THAT DOESN/T LOOK LIKE IT/LL HAPPEN. HAVE ALSO BROUGHT THE PCPN INTO NORTHERN NY A TAD FASTER THAN IN PREVIOUS ZFP. IR SAT PIX SHOW SOME EROSION OF THE LOW-LVL CLDS ACRS WESTERN QUE/EASTERN ONT ATTM. HOWEVER...MID CLDS MAKING QUICK PROGRESS ACRS THE GREAT LKS REGION WILL BE RIGHT ON THEIR HEELS. ST LAW VLY/NORTHERN ADIRONDACKS MAY SEE SOME BRIEF CLEARING OVRNITE...BUT IT WON/T LAST LONG. BASICALLY...FA TO STAY IN BKN CLDS ALL NITE TONITE. KCXX 88D HAS SHOWN SHSN IN NW FLOW ACRS THE HIR TRRN OF GREEN MTNS ALL EVENING. HAVE OPTED TO HIGHLITE THESE IN THE STF THIS EVENING AND WILL CONTINUE TO DO SO INTO THE OVRNITE PERIOD IN WESTERN AND SRN VT. OVER NE VT...WILL JUST MENTION SCT FLURRIES IN THE OVRNITE PERIOD. HAVE BUMPED MOST OVRNITE LOW TEMPS DOWN A TAD BASED ON CURRENT OBS TRENDS. 20Z LAMP DATA SHOWS THAT TEMPS MAY ACTUALLY RISE A BIT TOWARD MORNING ON THE NY SIDE. ALL OTHER CHANGES TO ZONES COSMETIC. WORK ZONES OUT. FINAL ZFP AT 10 PM AFTER A QUICK LOOK AT THE LATEST OBS. .BTV...NONE. MURRAY vt AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NORTHERN INDIANA 330 AM EST THU APR 6 2000 FIRST PROBLEM IS WINDS SPCLY NRN FA...ETA BUFKIT SHWNG MOMENTUM XFER OF 39 KTS ACRS NRN FA THIS AM WHICH SEEMS REASONABLE WITH AM SUN AND COORD WITH DTX. WL ONLY MENTION WINDY 20-30MPH SRN ZNS. TEMPS TRICKY WITH FRONT THOUGH ALL BUT FAR SERN ATTM...SIG COOLING OF LOW LVL TEMPS BUT SOME RECOVERY IN SUN/DRY ATMOS ANTICIPATED...WL ALLOW TEMPS TO RECOVER TO NR NGM MOS. SOME MODEL DISCREPENCIES WITH LTST MODELS WITH DY2 NRN STREAM WAVE DIGGING SE INTO THE MID MS VLY. PER LTST RUC V12Z ETA SEEMS BEST EARLY WITH AVN/NGM TOO STRONG. STRONG FGEN BNDRY DEVLOPING ACRS FA QUESTION IS WHETHER/WHERE DEPTH OF COLD AIR WILL INHIBIT CONVECTION FRI AFTN. GAVE NOD TO THE ETA FOR NOW...AVN BY F48 FASTEST AND NGM MAY BE CONTG TOO STRONG WITH MIDLVL JET ROTATING THROUGH BASE OF TROF. NONETHELESS SIG CHCS FOR STRONG/SVR CONVECTION DY2. MOVEABLE POINT ETA SNDGS YIELDING HIGH 0-3KM SR HELICITY IN EXCESS OF 300 M2S-2...8.7KFT WB0...STEEP LAPSE RATES AND SOME CAPE REALIZED ABOVE 900 MB. LOW BRN IN STRONGLY SHEARED ENVIRONMENT BUT AT LEAST SERN FA SHOULD HAVE ENOUGH FORCING FOR SUPERCELL POTNL. WILL MENTION MINIMAL HEIGHTENED WORDING DY2 ACRS SRN 2/3RDS FA. THREAT LESSENS SIGNIFICANTLY WITH DEPTH OF COLD AIR ACRS NRN ZNS/NR TRIPLE POINT. MISFWA AVBL. .IWX...NONE PBM in AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE ST LOUIS MO 300 AM CDT THU APR 6 2000 WDLY SCT TSRA HAS MSTLY TAPERED OFF AS AMS BCMS MORE STBL BHND CDFNT ACRS SRN MO. 06Z SFC ANLYS SHOWD SMWHT DEEPER SFC LOW OVR OK/TX PNHDL THAN MODELS FCST. 06Z RUC HAS BTR HNDLE SO WL FOLLOW THIS FOR FIRST PD...BUT AVN NEXT BEST FOR LTR PDS. CDFNT TRAILS FROM SFC LOW OVR GRTLKS THRU IN/IL/SRN MO TO WMFNT ACRS SRN KS AND LOW IN WRN OK. WMFNT WL RMN OVR SRN MO TODAY AS PER AVN AND BGN TO LIFT NWD TONIGHT AS ZONAL FLOW QUICKLY AMPLIFIES AND OK SYS MERGES WITH NEW DVLPG LOW. FAVOR HIGHER FAN POPS TONIGHT AND FRI WITH WMFNT IN PLACE...QG SUPPORT ALOFT...AND NOSE OF 300 JET DIGGING THROUGH AREA. PROBABLY NEED TO ADD CHANCE FRI NIGHT/SAT MORN AS DEFORMATION ZONE WORKS THRU AREA. NO CHANGES TO EXTENDED ATTIM EXCEPT TO ADD LINGERING 30 PERCENT POP FOR ERN ZONES SAT. .STL...NONE LENNING mo AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 130 AM EST THU APR 6 2000 DISC: EARLY MORNING MID/HI LVL CLDS MOVING ALONG WITH VORT LOBE WILL MAKE FOR COLORFUL SUNRISE...THEN DISSIPATE WITH 80H WAA TODAY. TODAY FAST 80H FLOW(GOES SOUNDING DATA)WILL TRANSLATE TO SURFACE WITH WINDS GUSTS PEAKING AT TIMES 30 MPH. DOWNSLOPE TO BRING TEMPS ABOVE MOS FCST TODAY BY ABOUT 3 DEG. 05Z RUC SHOWING 70-90% MEAN RH IN PENN AND COMPOSITE RADARS SHOWING STRIPE OF PCPN BUT MOST IF NOT ALL IS VIRGA. ON FRIDAY AVN SHOWING SOME WEAK FGEN FORCING AT 80H WITH LOW LVL DIR/SPEED SHEAR MARKING THE WARMFRONT. NOT ENOUGH DYNAMICS TO BRING MORE THAN A FEW SPRINKELS FRI AFTERNOON SO PARTLY SUNNY WILL BE THE GENERAL CONDITION. MOS TEMP NO HIGHIER THAN 60S WITH WARMFNT W-E THRU CFA. WILL SHADE TOWARD COOLER TEMPS. AT 2 THIS MRNG MIV BELOW FREEZING AND ACY 33. DEFINITELY FROST ON THE CAR THIS MORNING. STRONG S/W DIGGING INTO HEARTLAND WITH SHARPENING UPPER TROUGH WILL BRING THE NEXT CHANCE OF PCPN. TIMING DIFFERENCES WITH ETA -NGM/AVN. ETA WANTS TO BRING IN PCPN FASTER FRI NIGHT WHILE NGM/AVN NOT UNTIL SAT. HAVE COMPROMISED AND KEPT OUT OF ALL BUT FAR NRN ZNS. WITH DEEPING TROUGH PCPN WILL BE HELD UP FROM MOVING ACROSS CFA ON SAT AND THAT INCREASES THE LIKELYHOOD OF THERMODYNAMICS ADDING TO THE POTENTIAL FOR TSTMS. UPCOMING SETUP A LITTLE MORE PROMISING THAN LAST PCPN EVENT TO BRING EARLY LINE OF CONVECTION FOLLOWED BY A STEADY RAIN LATE SAT INTO SUN MORNING. VERY IMPRESS VORT MAX OF 40 UNITS. SAT HOWEVER WILL NOT BE A WASHOUT UNTIL LATER IN THE DAY. WATCHING EXTENT OF CAA ON SUN INTO MON NIGHT FOR THE CHANCE OF FREEZING TEMPS OR FROST. APRIL SHOWERS TO BRING MORE MAY FLOWERS AFTER A VERY VERY WET MARCH. ILG INXCESS OF 9 INCHES PHL 6 AND ACY/ABE 5 INCHES. THE MORE PCPN THE BETTER NEXT FEW WEEKS TO HELD WARD OFF THE PTNL FOR DROUGHT. WINDS W/B PICKING ON THE COAST AS WELL TODAY AND SMALL CRAFT ADV W/B RAISED WITH THIS PCKG. .PHI...SMALL CRAFT ADVISORY SANDY HOOK NJ TO FENWICK ISLAND DE OUT 20 NM AND DEL BAY. SEE YA EBERWINE pa WEST CENTRAL AND SOUTHWEST FLORIDA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TAMPA BAY AREA - RUSKIN FL 900 AM EDT THU APR 6 2000 THIS MORNINGS SOUNDING AND THE RUC BASICALLY CONFIRM WHAT THE CURRENT FORECAST IS RUNNING. THERE IS A LITTLE MORE MOISTURE THAN YESTERDAY BUT WITH A PWAT OF .23 INCHES IF WE SEE A CLOUD OUT THERE IT WILL BE REAL LONELY. WATER TEMPERATURES COOLED QUITE A BIT OVERNIGHT WITH THE WATER TEMPERATURE AT EGMONT DROPPING TO 69.6 DEGREES AND 63 DEGREES AT HOMOSASSA. WITH THOSE KIND OF WATER TEMPERATURES WE SHOULD SEE A PRETTY GOOD SEABREEZE. THE ONLY CHANGE I PLAN TO MAKE IS TO LOWER TEMPERATURES THIS AFTERNOON ALONG THE COAST. THE COASTAL LOOK GREAT...NO CHANGES ARE PLANNED. HUMIDITIES WILL BE VERY LOW AGAIN THIS AFTERNOON...BUT LUCKILY WINDS WILL NOT BE A FACTOR IN FIRE DANGER. BUT WITH THE EXCEPTION OF SEABREEZE INFLUENCED AREAS HUMIDITIES WILL BE BELOW RED FLAG CRITERIA FOR MOST OF THE AFTERNOON. .TBW...RED FLAG WARNING ALL COUNTIES EXCEPT THOSE AREAS WITHIN 20 MILES OF GULF COAST. FIRE WEATHER WATCH FOR THE COASTAL COUNTIES AREAS WITHIN 20 MILES OF THE GULF COAST. FIRE WEATHER WATCH IN EFFECT FRIDAY FOR INLAND ZONES 43-52-56- 57-61 SOBIEN fl AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN 1030 AM CDT THU APR 6 2000 FORECASTS HAVE BEEN UPDATED TO ADD SOME CLOUDINESS. LATEST RUC MODEL INDICATES HIGH LEVEL MOISTURE WILL INCREASE OVER AREA AND CLOUDINESS NOW IN DAKOTAS WILL SPREAD EAST. LOW LEVEL LAPSE RATES SUFFICIENT FOR CUMULUS FORMATION IN ERN ZONES AS WELL. BASED OF FORECAST SOUNDINGS AND LATEST RUC MODEL FORECAST HIGH TEMPERATURES HAVE BEEN RAISED SLIGHTLY. .MSP...NONE. SCOTT mn AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON NC 945 AM EDT THU APR 6 2000 NO CHANGES PLANNED W/ THIS UPDATE. UA ANALYSIS INDICATES ZONAL/NEARLY DOWNSLOPE FLOW OVER REGION THIS MORNING W/ SFC HI PRES OFF THE E CST OF FL IN CONTROL. SAT PIX/OBS SHOW SKC CONDITIONS & AREA SOUNDINGS BONE DRY SO SUNNY SKIES TO CONTINUE. LO-LVL THICKNESS SCHEMES GIVE MID 70S THROUGHOUT BUT FCST MAX TEMPS OFF RAOBS IN LWR 80S. LAMP GUIDANCE SHOWS 75-80 BUT TEMPS ALREADY A COUPLE OF DEGS WARMER AT 13Z. WILL LEAVE IN UPR 70S FOR NOW. SOUNDINGS & VWP SHOW 25-30KT JUST OFF THE SFC WHICH ARE BEGINNING TO MIX DOWN. WINDS ALREADY G20KT AT ILM & G18KT AT MYR. CWF: WINDS SLOWLY BUILDING AT FPSN7 & 41004 AS GRAD BETWEEN HI & FNT TO OUR N TIGHTENS. 12Z RUC KEEPS SRN WATERS BELOW CRITERIA WHILE 06Z ETA BRINGS IN 25KT. BASED ON CURRENT READINGS WILL LEAVE FLAGS ALONE & LET FCSTS RIDE. .ILM...SMALL CRAFT ADVY SURF CITY NC TO LITTLE RIVER INLET SC. LGE nc SOUTHWEST ARIZONA/SOUTHEAST CALIFORNIA FORECAST DISCUSSION NATIONAL WEATHER SERVICE PHOENIX AZ 940 AM MST THU APR 6 2000 .SYNOPSIS... A HIGH PRESSURE SYSTEM WILL CONTINUE TO PRODUCE ABOVE NORMAL TEMPERATURES OVER ARIZONA THE NEXT FEW DAYS. A PACIFIC LOW PRESSURE SYSTEM IS FORECAST TO MOVE INTO THE WESTERN STATES THIS WEEKEND... PRODUCING BREEZY TO WINDY CONDITIONS IN ARIZONA...ALONG WITH A COOLING TREND SUNDAY AND MONDAY. OTHERWISE...SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA WILL REMAIN DRY INTO EARLY NEXT WEEK. .DISCUSSION... LIGHT TO MODERATE WESTERLY ALOFT AS SHOWN ON 12Z SOUNDINGS HANDLED VERY GOOD BY 00Z MODELS. MY ANALYSIS WOULD SHOW A FLAT UPPER RIDGE NOW TRAVERSING THE STATE...COMPARED TO SEVERAL WEAK RIPPLES THAT ARE DEPICTED ON LATEST RUC. NOTE ERROR ON RUC 500MB INITIALIZATION INVOF FGZ. IN ANY CASE...DRY WX TO CONTINUE AS FURTHER AMPLIFICATION TAKES PLACE ACROSS OUR CWFA TONIGHT AND FRIDAY. IN FACT THE 500MB HEIGHTS NOW APPEAR 20-30M HIGHER FRIDAY MORNING OVER IMP/YUMA COMPARED TO PREV ETA OUTPUT. AND BY SATURDAY MORNING NEW ETA PUSHES RIDGE AXIS RIGHT OVERHEAD FOR ANOTHER 20-30M RISE. WITH CLOSED LOW REMAINING WELL OFFSHORE AND DIFLUENT 200-300MB WINDS CONTINUE...WE SHOULD SEE CI CLOUDINESS ADVANCE ACROSS THE STATE. MOSTLY THIN CI TO HAVE LTL OR NO AFFECT ON TEMPS. AVIATION AND PUBLIC FCSTS IN GOOD SHAPE. SIPPLE N az