NORTHERN ARIZONA FORECAST DISCUSSION NATIONAL WEATHER SERVICE FLAGSTAFF AZ 300 PM TUE MAR 28 2000 SYNOPSIS...RAIN AND HIGH ELEVATION SNOW SHOWERS...ALONG WITH ISOLATED THUNDERSTORMS...WILL CONTINUE THROUGH THIS EVENING WITH SHOWER ACTIVITY DECREASING OVERNIGHT. SEVERAL WEAK DISTURBANCES WILL MOVE ACROSS THE STATE OVER THE NEXT FEW DAYS AND WILL BRING A CHANCE FOR SHOWERS EACH DAY. HIGH PRESSURE WILL BEGIN A DRYING AND WARMING TREND BY THE WEEKEND. DISCUSSION...LOW PRESSURE SYSTEM ALOFT HAS MOVED INTO CENTRAL NM DURING THE DAY. DEEP MOISTURE AND LOW CLOUDS COVERS MUCH OF THE STATE THIS AFTERNOON WITH AREAS OF LIGHT RAIN AND MOUNTAIN SNOW SHOWERS...AND A FEW THUNDERSTORMS...CONTINUING. FLOW ALOFT HAS BECOME WEAK ON THE NORTH SIDE OF THE NM CIRCULATION WITH A WELL-DEFINED DEFORMATION ZONE PRESENT OVER CWFA. NEXT WAVE UPSTREAM IS ALREADY MOVING INTO THE CWFA THIS AFTERNOON WITH AN INCREASE IN WINDS ALOFT AND STEEPENING THE LAPSE RATES SLIGHTLY. LI'S ARE IN THE -2 TO -4 RANGE THIS AFTERNOON AND WILL REMAIN UNSTABLE INTO THE EARLY EVENING HOURS. THUS...EXPECT SHOWERS AND THUNDERSTORMS TO PERSIST FOR AT LEAST A FEW HOURS INTO THE 1ST PERIOD. RUC AND ETA SIMILAR IN THIS FEATURE AND INDICATE THAT PRECIP ACTIVITY WILL DIMINISH THIS EVENING FROM WEST TO EAST...BUT PROBABLY NOT END COMPLETELY...ESPECIALLY IN THE NE ZONES. ETA AND AVN CONTINUE TO EXHIBIT BROAD CYCLONIC TROUGH DEVELOPING OVER THE SOUTHWEST THROUGH 4TH PERIOD. THIS WILL LIKELY KEEP TEMPS NEAR OR BELOW SEASONAL NORMALS AND MAINTAIN A CHANCE OF SHOWERS EACH DAY. EXTENDED...ECMWF...MRF...AND CDN MODELS VERY SIMILAR IN ALLOWING CLOSED LOW TO SAG TO THE SOUTHWEST DURING THE EXTENDED PERIOD. DIFFERENCES ARISE AS TO HOW FAR TO THE SOUTHWEST IT WILL GO...WHEN IT WILL EJECT...AND TRAJECTORY OF SYSTEM WHEN/IF IT EJECTS. FOR NOW WILL GO WITH UNSETTLED WEATHER ON DAY 3 AND DECREASE CLOUDS WITH WARMING TEMPERATURES ON DAYS 4 AND 5. DB. .FGZ...NONE. az SOUTH CENTRAL AND SOUTHEAST COLORADO AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE PUEBLO 103 PM MST TUE MAR 28 2000 ...FORECAST CHALLENGE WILL BE TIMING AND AMOUNT OF PRECIPITATION TONIGHT ACROSS FORECAST AREA... CURRENTLY ACROSS THE REGION A BROAD TROUGH OF LOW PRES LAY ACROSS THE GREAT BASIN...WHILE AT THE SFC LOW PRES WAS LOCATED ACROSS NE NEX MEXICO/SE COLORADO. ABUNDANT CLOUD COVER WAS FOUND ACROSS THE CWA...ESPECIALLY OVER THE SAN LUIS VALLEY AND WESTWARD AS PER VISIBLE SATELLITE IMAGERY AND SFC OBS. ALSO...A FEW LTG STRIKES ARE BEING PICKED UP BY AWIPS OVER N NEW MEXICO. SPOTTER REPORTS THIS AFTN INDICATE VERY LIGHT SNOW AT WOLF CREEK AND MONARCH SKI AREAS. TEMPS ACROSS THE SAN LUIS VALLEY AND E PLAINS HAVE BEEN GENERALLY IN THE 50S TO NEAR 60. TONIGHT AND WEDNESDAY...A PAIR OF UPPER LEVEL DISTURBANCES...ONE NORTH AND ONE SOUTH OF CO...MOVING THROUGH THE FLOW WILL CONTINUE THICKENING CLOUDS AND PCPN CHANCES ACROSS THE CWA TONIGHT THROUGH WED MORNING. HOWEVER...500 MB VORT CHARTS SHOW THAT THESE SHORTWAVES TEND TO WEAKEN AND BREAK APART AS THEY MOVE ACROSS THE AREA. OTHER THAN THE SHORTWAVES...THE MOISTURE ENTERING THE AREA HAS VERY LITTLE TO WORK WITH TO BRING ABOUT ANY SIGNIFICANT PCPN. LATEST RUC ANALYSIS INDICATES PCPN WEST OF THE CONT DIVIDE THROUGH WED 06Z...WITH VERY LITTLE TO NIL EAST OF THE MTNS. I STILL BELIEVE THAT SHOWERS WILL DEVELOP IN THE EAST...BUT WILL RETHINK THE STRENGTH OF THE SHOWERS...AND WILL STALL DEVELOPMENT EVEN FURTHUR. THEREFORE WILL DROP LIKELYS IN THE EAST AND GO WITH 30-40% POPS...AND HAVE PCPN EAST OF THE MTS START OVERNIGHT...MOST LIKELY AFTER MIDNIGHT. ETA DIVQ CHARTS INDICATE UPWARD MOTION ACROSS CWA THROUGH WED 12Z...THEN DOWNWARD MOTION MOVING IN AROUND 18Z. THIS LEADS ME TO THINK THAT ANY SHOWERS OCCURRING TOMORROW MORNING WILL BEGIN TO TAPER OFF BY AROUND NOON...LATER FARTHUR OUT EAST...AND REGION WILL PROBABLY SEE SOME CLEARING OF THE CLOUDS FOR THE LATE AFTERNOON INTO THE EVENING. ONE NOTE...PREVIOUS FORECAST THINKING WAS THAT THERE WAS A CHANCE FOR POSSIBLE MARGINAL SEVERE STORMS FOR THE FAR E PLAINS WED AFTN...DUE TO FAVORABLE SHEAR AND CAPES. SOMEWHAT SKEPTICAL AT THIS TIME...BUT WITH INCREASED INSOLATION DUE TO CLEARING SKIES WED AFTN...CONVECTION IS NOT OUT OF THE QUESTION. WILL KEEP MENTION OF A FEW POSSIBLE THUNDERSTORMS WED AFTN FOR THE FAR E PLAINS. AS FOR TEMPS...LITTLE CHANGE AT 700 AND 850 MB. CLOUD COVER TONIGHT WILL HELP TEMPS MODERATE...WHILE HIGH READINGS WED WILL BE COMPARABLE TO TODAYS HIGHS. WEDNESDAY NIGHT AND THURSDAY...THE LOW TROUGH OVER THE GREAT BASIN GETS MORE DEFINED WED NIGHT...AND BY EARLY THURS MORNING A LOW CLOSES OFF OVER UTAH AND STARTS TO DROP S-SW. ETA CROSS-SECTIONS INDICATE THAT BY THURS AFTN AND EVE DEEP MOISTURE SETS UP ACROSS THE ENTIRE CWA...WITH A STRONG E-NE UPSLOPE FLOW. THURSDAY SHOULD START OFF RELATIVELY MILD AND PARTLY CLOUDY...BUT CONDITIONS WILL DEVELOP RAPIDLY AND BY THE AFTERNOON CLOUDS SHOULD BE MOSTLY CLOUDY TO OVERCAST. THURS NIGHT...CONDITIONS WILL BE VERY FAVORABLE FOR PCPN REGIONWIDE. EXTENDED...(FRI-SUN)...THE LOW PRES SYSTEM OVER UTAH ON THURS IS PROGGED TO DROP TO THE SW ACROSS SOUTHERN CA...PROVIDING ANOTHER CHANCE FOR PCPN ON FRI. SAT AND SUN IT CONTINUES SW AND STRENGTHENS...SETTING UP OFF THE CA BAJA...AND DROPPING FAR ENOUGH S FOR A COUPLE OF DAYS OF DRY WEATHER FOR THE REGION. .PUB...NONE. MOORE co AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TALLAHASSEE FL 834 PM EST TUE MAR 28 2000 ONLY MINOR CHANGES PLANNED FOR EVENING UPDATE OF ZONES. CLOUDS ACROSS N AL AND CENTRAL GA PROGGED TO STAY N OF CWFA PER 18Z ETA AND LATEST RUC SO CLEAR SKIES SHOULD DO IT. MAY SEE MVFR VISIBILITY RESTRICTION WITH NEAR ZERO DEW POINT DEPRESSION...BUT NOT SIGNIFICANT ENOUGH TO MENTION IN ZONES. TEMPS LOOK REASONABLE. ONLY MINOR ADJUSTMENTS WILL BE MADE. MARINE: BL WIND FORECAST HAS WINDS INCREASING A BIT LATE AND WILL INDICATE THIS IN 1030 PM PACKAGE WITH WINDS BECOMING S TOWARD MORNING. .TLH... AL...NONE GA...NONE. FL...NONE. WOOL fl AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GAYLORD MI 400 PM EST TUE MAR 28 2000 BROAD CYCLONIC FLOW AT LOW LEVELS CONTINUES ACROSS THE WESTERN GREAT LAKES REGION. Q-G FORCING REMAINS MINIMAL... HOWEVER WEAK LOW LEVEL CONVERGENCE ALONG WITH THE DAYTIME HEATING (SFC-500 MB INSTABILITY)...SHOWER ACTIVITY HAS BEEN ABLE TO BECOME A LITTLE MORE WIDESPREAD THIS AFTERNOON AS PER MOSAIC RADAR LOOPS. IN ADDITION...WITH FREEZING LEVELS AROUND 3000-3500 FEET MSL ALONG WITH THE HIGH DEGREE OF SFC-500 MB INSTABILITY (500 MB TEMPS AROUND -32C AND TOTAL-TOTALS IN THE MID/UPPER 50S)...DEEPER CONVECTION HAS RESULTED IN AREAS OF SLEET/SMALL HAIL. MODIFIED RUC/LAPS SOUNDINGS IN FACT SHOW CONVECTIVE EQUILIBRIUM LEVELS JUST ABOVE 500 MB... CORRELATING WELL WITH THE CONVECTIVE CLOUD TOPS PER THE LATEST IR LOOPS (WITH TEMPS AROUND -35C). INITIAL FORECAST CONCERN WILL BE WITH DIURNALLY-DRIVEN SHOWER ACTIVITY (ALONG WITH PRECIP TYPE)...NEXT CONCERN WILL BE WITH PRECIP CHANCES ON THE EAST SIDE OF THE STATE AS WEAK VORT LOBE ROTATES AROUND BACK SIDE OF UPPER LOW. SHORT TERM DISCUSSION...WILL CONTINUE WITH SCATTERED SHOWER WORDING THIS EVENING IN MOST ZONES (BOTH RAIN AND SNOW MENTION)... PARTICULARLY OVER THE SRN AND SW PORTIONS OF NRN LWR WHERE THE ECHOES ARE MOST PREVALENT. DIMINISHING DIURNAL INSOLATION (LOWERING SFC LAYER TEMPS) WOULD INCREASE THE LIKELIHOOD OF MORE SNOW THAN RAIN...THOUGH AT THE SAME TIME WILL DIMINISH THE ACTIVITY AS WELL. AFTERWARDS...WILL INCLUDE HIGHER POPS ACROSS ERN PORTIONS OF UPPER MI AND NRN LWR GIVEN THE INCREASED Q-G FORCING (PDVA AND 850-500 MB Q-VECTOR CONVERGENCE) IN RESPONSE TO THE VORT LOBE ROTATING ON THE BACK SIDE OF THE UPPER LOW. THIS AREA OF MORE WIDESPREAD CLOUDINESS/ SCATTERED PRECIP IS CURRENTLY N OF LAKE HURON ACROSS ONTARIO...MOVING SOUTH. OTHERWISE...PRECIP PROBABILITIES ACROSS THE WESTERN SIDE OF ERN UPR/NRN LWR MI WILL BE PRIMARILY IN THE EVENING. HIGHLY-AMPLIFIED UPPER FLOW PATTERN CONTINUES ON WED...THOUGH WITH CLOSED LOW PULLING A LITTLE FARTHER EAST OF THE REGION. THE Q-G CHARTS SHOW INCREASED UPPER CONVERGENCE/SUBSIDENCE AS THE UPPER HEIGHTS BUILD BEHIND THE TROUGH. WITH THE INCREASED SUBSIDENCE... MODEL SOUNDINGS SHOW THE LOWER-MID LAYERS DRYING OUT WITH... DESPITE SIMILAR 925-850 MB TEMPS AS TODAY...WARMER TEMPS BETWEEN 800-500 MB (LOWERING SUBSIDENCE INVERSION). THIS WILL LIMIT THE EXTENT/ DEPTH OF DIURNAL CLOUD COVER AS THE DAY PROGRESSES...THUS HAVE WORDED BECOMING MOSTLY SUNNY IN ALL ZONES BY AFTERNOON. MUCH THE SAME STORY WED NIGHT AND THU...WITH DRY WEATHER TO CONTINUE AS REGION REMAINS IN BETWEEN UPPER RIDGE AND TROUGH AXES (MAINTAINING THE UPPER CONVERGENCE/Q-VECTOR DIVERGENCE/SUBSIDENCE). EXTENDED DISCUSSION...MRF AND ECMWF CONTINUE TO BE IN DECENT ACCORD THROUGH THE WEEKEND WITH OVERALL UPPER FLOW PATTERN...THOUGH WITH ECMWF SURFACE FEATURES DO NOT MATCH UP AS WELL WITH UPPER LEVEL FEATURES. CANADIAN ENSEMBLES HAVE BEEN CONSISTENT OF LATE...HOWEVER THIS MODEL REMAINS THE OUTLIER COMPARED TO THE MRF/ECMWF FROM SUN THROUGH TUE. CANADIAN SHOWS A REX BLOCK BY SUN OVER THE WEST (RIDGE OVERTOP CUTOFF LOW)...WITH A TROUGH ACROSS THE ERN CONUS. THE MRF AND ECMWF INSTEAD SHOW A MEAN TROUGH OUT WEST (WITH CLOSED LOW IN THE SWRN STATES AS WELL)...WITH RIDGE BUILDING IN THE ERN CONUS ON SUN FOLLOWING INITIAL SHORTWAVE ON SAT. GIVEN MODEL TRENDS OVER THE PAST COUPLE OF DAYS...WITH THE ACTIVE NRN BRANCH ACROSS THE PACIFIC NW... WILL AGAIN FOLLOW MRF/ECMWF SOLUTIONS. THE INITIAL EXTENDED FORECAST CONCERN IS WITH RAIN CHANCES ON FRI ASSOCIATED WITH WEAK NRN STREAM SHORTWAVE. EXTENDED RUNS...ALONG WITH LATEST (12Z) AVN...HAVE ALL TRENDED TOWARD A SLOWER EWRD PROGRESSION OF THIS FEATURE...WITH THE SFC TROUGH NOW PROGGED TO REACH THE WESTERN PTN OF LOWER MI BY 12Z SAT. WITH THE LOW-LEVEL RIDGING/DRY AIR LIKELY TO HANG ON DURING THE DAY FRIDAY...HAVE RE-WORDED RAIN CHANCES FOR THE OVERNIGHT FRI-SAT. TRICKER FORECAST IS WITH SUN AHEAD OF MAIN SYSTEM. AGAIN...MRF AND ECMWF SHOW BUILDING HEIGHTS BEHIND INITIAL VORT LOBE AND NEXT (MAIN) UPPER TROUGH. THIS WOULD SPELL A WARMUP ALONG WITH MINIMAL RAIN CHANCES ON SUN AND PERHAPS MOST OF MON (WAA/ISENTROPIC LIFT IS NOTED...THOUGH MOISTURE APPEARS LIMITED). HOWEVER...GIVEN THE SO-SO RUN-TO-RUN CONTINUITY OF LATE...WILL FOR NOW MAINTAIN A CHANCE OF SHOWERS WITH THE DEVELOPING WARM ADVECTION PATTERN. .APX...NONE. HURLEY mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DULUTH MN 850 PM CST TUE MAR 28 2000 EASTWARD MVMNT OF CLOUDS HAS SLOWED AND NE FLOW AHEAD OF RIDGE HAS CAUSED CANADIAN CLOUD BANK TO BEGIN SLIDING S. SFC RIDGE IS BUILDING SOUTH INTO MN AS THE STACKED LOW OVER THE NE IS HOLDING ITS POSITION. NEW RUC AND EARLY MODEL PIX SHOW CLOUDS SHOULD OVERSPREAD/LINGER IN THE E 2/3RDS OF CWA THRU THE REST OF THE NIGHT. THE H85 RH FIELD SEEMS TO BE CONTOURING THE AREA OF CLOUDS WELL AND FOLLOWED THAT FOR TIMING. WILL GO MORE PESSIMISTIC WITH CLOUDS IN ALL EXCEPT FAR WESTERN ZONES. WILL ADJUST TEMPS UP SLIGHTLY IN CLOUDY AREAS WITH REDUCED RADIATIONAL COOLING. .DLH...NONE. SHIMON mn AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON NC 855 PM EST TUE MAR 28 2000 LATEST INITIALIZATION OF THE RUC AND MSAS QUITE CLOSE. RUC DOES TAKE THE FRONT INTO THE CSTL WATERS BY 06Z...AND BEYOND BY 09Z. DO NOT SEE ANY REASON WHY THIS SHULD NOT TRANSPIRE AND WILL WORD FCST ACCORDINGLY. NO SHOT OF PCPN AND SINCE BEST DYNAMICS AND MOISTURE REMAIN N OF THE FA. ONLY FLY IN THE OINTMENT WILL BE THE MODEST SFC PG. WINDS WILL CONTINUE AT HIGH SPEEDS ESPECIALLY CLOSER TO THE COAST BUT BELOW ADV CRITERIA...AND IF STATEMENTS NEEDED...NOWS SHULD COVER. OVERALL...WNDS ALOFT MAINLY FROM THE W...AND IF ANY CLDINESS IT WILL BE THE HIGH LEVEL TYPE...NOT ENUF TO DETOUR A MSTLY SLC NITE. TEMPS...CULD POSE A PROBLEM SINCE MIXING WILL PREVALENT FOR THE REMAINDER OF THE NIGHT. CURRNT PRESCRIBED MINS MAY BE A BIT TOO LOW....WILL TWEAK UPWARD. CWF...BONAFIDE SCA CONDITIONS AND EXPECT THEM TO CONTINUE ALL NIGHT ESP WITH PG PRIOR TO AND AFTR FRNTL PASSAGE. ONLY SLIGHT MODIFICATION EXPECTED BASED ON LATEST OBS. .ILM...SMALL CRAFT ADVISORY AMZ250-252-254-256. DCH nc FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND 841 PM CST TUE MAR 28 2000 ...TEMPS/HI CLOUDS ONLY EVENING FORECAST CONCERNS... SFC RDG AXIS RELUCTANT TO SHIFT E THIS EVE...ALTHO LGT E/NE FLO HAS DVLPD ARND KGFK AND KFAR. BOTTLED UP ATMSPHRE FEATURING STACKED LO OVER NE WITH RIDGING IN ONTARIO AND NEXT TROF HAVING TROUBLE MOVING E FROM PAC NW. H5 00Z PLOT INDICATES WEAK PRES FALLS ENTERING FAR SW ND AS U/L FLO TURNS SW AHEAD OF TROF AXIS IN ERN ID. U/L RDG AXIS THO STUBBORNLY HOLDING OVER CNTRL ND AND SCHEDULED TO DO SO THRU THE NGT. LATEST ETA/RUC MODELS IN FACT INCREASE SFC PRESURES OVER CWA AFTR 06Z WITH MSAS PRES CHANGE FIELDS ALSO BACKING OFF ON ANY FALLS THIS EVE. A FEW BANDS OF CI HAVE MADE IT AS FAR E AS A DVL/JMS/SARGENT CO LINE THIS EVE (THINNING AS THEY MOVE NE) WITH BULK OF DEEPER MOISTURE SEEN RIDING N INSTEAD OF E ACRSS ERN MT VCNTY OF INVERTED TROF FEATURE BTWEEN KHVR AND KGGW. H85-H7 WAA IN NCNTRL SD IGNITING AREA OF AC...PROGGED TO MOVE SLOLY NE OVNGT...STAYING MAINLY SW OF CWA. TEMPS SLOLY FALLING THIS EVE WITH E/SE FLO ON ND SIDE NEAR 10KTS KEEPING SUM MIXING GOING. NEAR CALM CONDITONS NW MN MAY ALLOW FASTER DROPS BFRE SUM E/SE GRAD BEGINS THERE. OVERALL...LATE MODELS CONTINUE TREND OF MILDER OVNGT LOWS PICKED UP ON DURING DAY SHIFT SO NO REAL TEMPS CHANGES NEEDED. ETA HINTING AT MID 20S FOR MUCH OF CWA AND THIS ACCOUNTED FOR WELL IN CURRENT ZONES AND MATCHES AREA-WIDE TD FIELD. MCLEAR/CLEAR WORDING FOR ALL OF CWA SHUD STILL WORK AS IT IS SETUP WITH ONLY EVE CHANGES XPCTD TO BE TWEAKING OF TIMING OF WINDS TURNING TO THE E/SE. .FGF...NONE. SOROKA nd FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND 955 AM CST TUE MAR 28 2000 FORECAST CHALLENGE FOR UPDATE CONCERNS CLOUD TREND AND TEMPS. VIS LOOP INDICATING BACK EDGE OF SC DECK OVR ARROWHEAD REGRESSING WEST SLIGHTLY ASSOCIATED WITH WK SFC TROUGH VCNTY LAKE SUPERIOR. RUC HINTED AT THIS LOOKING AT H925 MB RH BUT AS STACKED SYSTEM SHIFTS EAST TODAY WOULD NOT EXPECT MUCH MORE OF A WESTWARD SHIFT. LATEST SCANS FROM VIS ALSO SHOWING SOME EROSION ALONG THE WESTERN EDGE. WITH CYC FLOW CONTINUING AND SHALLOW LAYER OF GREATER RH FROM RUC MODEL SOUNDING AT H9-85 COULD SEE SOME CU DEVELOP ALTHOUGH H85 TEMPS NOT NEARLY AS COLD AS YSTDY AND CU RULES NOT VERY IMPRESSIVE. CURRENT FCST HAS PC OVR FAR EAST AND WILL CONTINUE TREND. REAMAINDER OF REGION SHOULD SEE NEARLY FULL SUN. TEMP ADVECTION FAIRLY NEUTRAL AND NOT ALOT OF MIXING WITH SFC HIGH OVR AREA. CURRENT READINGS FAIRLY UNIFORM ACROSS THE FA AND INLINE WITH FWC GUIDANCE SO NO SIG CHANGES PLANNED. SLIGHTLY STRONGER WINDS OVR EASTERN FA DEEPER IN CYC FLOW. .FGF...NONE. VOELKER nd AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CHARLESTON SC 1016 AM EST TUE MAR 28 2000 LTST SAT PICS SHO CLR SKIES ACRS RGN ATTM. SOME MID CLDS ALONG AND NW OF APPALACHAINS ASSCD WI APPCHG CDFNT. PLNTY OF DRY AIR IN PLACE AND WI VORTS REMNG WELL N OF THE RGN...CLDS WL DSPT AS THEY APPRCH CWA. THEREFORE WL CONT SNNY FCST. ? FOR TDY IS HOW STG WINDS WL GET. CAN COUNT ON ONE HAND TIMES WE HAVE HAD SUSTAINED WINDS OVR 25 KT (MINUS HURRICANES) IN JST PAST FEW YEARS...SO WL NOT GO OVRBOARD ON THIS JST YET. HWVR...RUC/MESOETA/ETA/NGM/AVN ALL CONSITENT IN DRIVING H8 45-50 KT JET ACROSS RGN LTR THS AFTN....WI 45 KT EVEN SHOWING UP AT H925 AND H950 ON RUC/MESOETA. WI FULL SUN AND APPCHNG CDFNT...SHUD HV NO PROBLM MIXING DOWN MAJORITY OF THS WIND. FOR NOW WL GO WI BECOMING WINDY EVERYWHERE...THO WL WTCH CLOSELY IN CASE ADVISORY NEEDED. TEMPS MOSTLY ON TRACK AND WL ONLY TWEAK UPWARD A LTL FOR SE GA. NO OTR CHANGES PLANNED. CWF...CURRENT OBSERVATIONS SHOWING A LULL FROM THE STRONGER OVERNIGHT WINDS ASSOCIATED WITH THE NOCTURNAL JET. HOWEVER...WINDS STILL EXPECTED TO INCREASE DURING THE AFTERNOON AS THE GRADIENT TIGHTENS. DO NOT ANTICIPATE ANY SIGNIFICANT CHANGES IN MORNING UPDATE. .CHS... SC...SMALL CRAFT ADVISORY S SANTEE RIVER SC TO SAVANNAH GA OUT 20 NM. LAKE WIND ADVISORY FOR AREA LAKES THIS AFTERNOON. GA...SMALL CRAFT ADVISORY SAVANNAH TO ALTAMAHA SOUND GA OUT 60 NM. LAKE WIND ADVISORY FOR AREA LAKES THIS AFTERNOON. WOODWORTH/JH sc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MORRISTOWN TN 1019 AM EST TUE MAR 28 2000 COLD FRONT ON PLATEAU. MOST OF THE SHOWERS HAVE MOVED OUT OF THE CWA. MESOETA AND RUC PROG THE FRONT THROUGH OUR AREA BY 18Z...BUT SATELLITE SHOWING ANOTHER SHORTWAVE OVER OH VALLEY. CLOUDS HAVE SCATTERED ACROSS THE VALLEY...WILL USE VARIABLE CLOUDINESS FOR THE CENTRAL AND NORTHERN VALLEY AND LOWER POPS A LITTLE SINCE PRECIP LOOKS FARTHER NORTH WITH THIS NEXT BATCH. STRONG WINDS WILL CONTINUE THIS AFTERNOON. WINDS GUSTING TO 30 ACROSS THE VALLEY. 850 WINDS PROGGED TO BE 40 KNOTS...BUT NO REPORTS OF TREES DOWN IN THE MOUNTAINS. WON'T ISSUE AN ADVISORY. TEMPERATURES SOARING OVER THE SOUTHERN VALLEY. WILL BUMP UP TEMPERATURES IN THE SOUTHERN ZONES. .MRX... NC...NONE. TN...NONE. VA...NONE. GH tn DEEP SOUTH TEXAS FORECAST DISCUSSION NATIONAL WEATHER SERVICE BROWNSVILLE TX 900 AM CST TUE MAR 28 2000 CURRENT RUC SFC WINDS SHOW OFFSHORE WILL MAINTAIN 15 KTS FM THE SE THRU 21Z...INCREASING TO 15 TO 20 KT BY 00Z. WL RAISE LAGUNA AND OFFSHORE TO 15 TO 20 KT AND GUSTY WITH "SCEC". SFC TROF EDGES TO BIG BEND BY 00Z...WITH TIGHT PGF OVR DEEP S TX. MEAN RH DECREASES DURING THE PM...ACCORDING TO RUC...AND XPCT SCT CONDITIONS BY AFTERNOON. RUC TIME/HEIGHT HAS MID LVL MSTR GONE BY NOON...AS VLY CURRENTLY HAS BKN DECK AT 18K FT ADVECTING E QUICKLY. TEMPS SHUD BE A CAT LWR THAN MON'S MID 90S...WITH LOWER 90S CONFINED TO WRN HIDALGO AND POINTS WEST...WITH BRO AND HRL 86-87 DEG F. WL MV TEMPS SLIGHTLY DOWN AND BETTER DEFINE FCST HIGHS. SYN...PHILO 58/MET INTERN...CASTILLO .BRO...SCEC ALL MARINE ZNS. tx AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE PADUCAH KY 300 AM CST WED MAR 29 2000 EARLY MORNING SURFACE ANALYSIS SHOWED HIGH PRESSURE CENTERED OVER FORECAST AREA (FA). OVERRUNNING CLOUD BAND AND ASSOCIATED PRECIP NOTED ON SATELLITE MOVING INTO SOUTHWEST SECTORS OF FA. LEADING EDGE OF THE MID CLOUD EXTENDS FROM SOUTHEAST KANSAS THROUGH SOUTHWEST MO AND INTO WEST TENNESSEE. MODEL SOLUTIONS APPEAR SIMILAR AND ABOUT 6 HOURS SLOW. NGM KEPT THE RH FIELD FURTHER SOUTH THAN THE MORE AGGRESSIVE ETA...WITH THE AVN THE "TWEENER". RUC ADDRESSING CURRENT WEATHER THE BEST...SO IT WILL BE USED IN SHORT TERM WITH AVN IN LATER PERIODS. FORECAST ISSUES WILL BE POPS AND TEMPS. ISENTROPIC UPGLIDE INDICATED ON I300K EXPLAINS THE LIFT ASSOCIATED WITH THE INCOMING CLOUDS AND LIGHT PRECIP. KLIT 29/00Z ESTIMATED SHOWALTER INDEX WAS NEAR ZERO. 5 MINUTE LIGHTING REPORTS SHOWED STRIKES AS CLOSE AS NORTH ARKANSAS AND WEST TENNESSEE...SO WILL MENTION THUNDER POSSIBLE ACROSS SOUTHERN TIER. DRY ATMOSPHERE (I.E. KSGF SOUNDING) WILL MUTE QPF VALUES BUT PROBABLY ONLY SLIGHTLY IMPACT POP (MAINLY IN SOUTH TIER OF FA). SURFACE LOW ON TRACK TO STAY SOUTH OF FA ...& CONTINUING NE-E LOW LEVEL WIND FLOW THROUGH THURSDAY. THIS TRACK WILL LIMIT POPS IN NORTH/NORTHEAST SECTIONS OF FA AND ALSO LIMIT DESTABILIZATION (I.E. LIGHT RAIN ONLY/NO THUNDER). CLOUDS WILL LINGER INTO THURSDAY...BUT LIFT AND ABUNDANT RH WILL HAVE TRACKED EAST WITH SURFACE LOW AS 500MB HEIGHT RISES BEGIN. TEMPS SHOULD BE SHUNTED BY CLOUD COVER AND COOL NE/E FLOW. ANTICIPATE TEMPS BELOW FWC/FAN VALUES. .PAH...NONE PAUL W ky AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAND RAPIDS MI 1030 AM EST WED MAR 29 2000 ...PARTIAL CLEARING BY LATE AFTERNOON... 500 SHTWV COMBINED WITH POCKET OF -8C 850 AIR OVER WI AT 12Z WILL ROTATE THROUGH CWA BY EARLY AFTERNOON. GRB SOUNDING... WHICH IS NEAR THE SHTWV AT 12Z...SHOWED CONSIDERABLE DRY AIR ABOVE 4000 FT. MEANWHILE...THE DTX SOUNDING DID NOT SHOW THE SUBSIDENCE INVERSION LIKE GRB DID AND WAS CONSIDERABLY MORE MOIST THROUGH 300 MB THAN GRB. SINCE THE SHTWV IS FCST TO ROTATE THROUGH THE CWA BY 18Z AND SINCE THERE ARE NO MID OR HIGH CLOUDS SHOWN ON THE IR IMAGES ASSOCIATED WITH THIS SHTWV... BELIEVE LATE MARCH SUN WILL ALLOW THE RUC SOUNDING TO VERIFY BETTER THAN THE ETA SOUNDINGS AND THAT IMPLIES CLEARING SKIES THIS AFTERNOON. THE RADAR DOES SHOW SPRINKLES OVER THE PARTS OF THE GRR CWA... BUT SINCE THE CLDS ARE NOWHERE NEAR DEEP ENOUGH TO GET ICE CRYSTAL FORMATION... ONLY SPRINKLES ARE EXPECTED. THESE ARE NOT BEING PICKED UP BY ASOS AND WOULD NOT BE EXPECTED TO. SO WITH THE VORT PASSING THROUGH BY EARLY AFTERNOON WILL UPDATE FORECAST TO SCATTERED SPRINKLES ENDING FOLLOWED BY PARTIAL CLEARING. HIGHS MID 40S NRN CWA AND 45 TO 50 SRN CWA (BASED ON RUC SOUNDINGS ALLOWING SOME SUN BY MID TO LATE AFTERNOON. .GRR...NONE. WDM mi AREA FORECAST DISCUSSION FOR CENTRAL/NORTHCENTRAL AND NORTHEAST SOUTH DAKOTA AND WEST CENTRAL MINNESOTA NATIONAL WEATHER SERVICE ABERDEEN SD 1030 AM CST WED MAR 29 2000 12Z UPPER AIR ANALYSIS HAS VERTICALLY STACKED TROUGHS 850 THROUGH 500MB. THIS INDICATES THAT THE SURFACE TROUGH WILL MOVE TO THE EAST ONLY SLOWLY AND RUC AGREES. WILL TAKE OUT MENTION OF SHOWERS FOR THE PIERRE AND MOBRIDGE AREAS SINCE THE RETURNS FROM THE 88D ARE DIMINISHING AND HIGHER RH IS STAYING FURTHER WEST. SATELLITE SHOWS THE CLOUDS ABOUT AS FAR AS THE JAMES VALLEY AT 15Z AND RUC HAS THE 500MB RH STREAMING INTO ALL BUT THE FAR NORTHEAST. ADDED A FEW MORE CLOUDS TO THE FORECAST THOUGH TEMPERATURES SHOULD CONTINUE TO CLIMB. WINDS NEAR THE SURFACE TROUGH WILL BE A LITTLE STRONGER SO INCREASED WINDS SOME ALONG THE RIVER. .ABR...NONE JCB/DLH sd SOUTHEAST TEXAS FORECAST DISCUSSION NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX 940 AM CST WED MAR 29 2000 VIS/IR IMAGERY AND KHGX SHOW SCATTERED SHOWERS AND THUNDERSTORMS IN THE NERN 1/4 OF THE CWA...AND RAPID CLEARING GENERALLY WEST OF I-35. THE MAIN FORECAST ISSUE IS TIMING AND HOW THAT AFFECTS SEVERE CONVECTION. THE 12Z CRP/BRO SOUNDINGS ARE STRONGLY CAPPED AND DEVOID OF SIGNIFICANT MOIST AIR ABOVE THE BOUNDARY LAYER...HENCE LITTLE OR NO CHANCE FOR CONVECTION. THE LCH/SHV/FWD SOUNDINGS HAVE WEAK CAPS...PLENTY OF MOIST AIR...AND LONG LINEAR HODOGRAPHS...HENCE GOOD CHANCES FOR SEVERE CONVECTION...PRIMARILY HAIL/WIND...TORNADOES NEAR LOCAL BOUNDARY ENHANCEMENT. THAT LEAVES HGX IN THE MIDDLE AS USUAL. THE MAIN LOW LEVEL FORCING WILL BE THE DRYLINE NOW IN WCNTRL TX. THE DRYLINE HAS MADE SOME PROGRESS IN SWRN TX AS EVIDENCED BY THE BIG DROP IN DEW POINT AT DRT THE PAST TWO HOURS. THE LATEST RUC RUNS INDICATE THE DRYLINE WILL REACH THE WRN BOUNDARY OF THE CWA AT 21Z. IN ADDITION...THE RUC INDICATES THE CAP WILL BE FULLY ERODED BY 18Z. AGREE WITH SPC AND GOING FORECAST FOCUSING ON THE NRN 1/2 OF THE CWA. OVERALL...THE FORECAST IS IN GOOD SHAPE. HOWEVER...AN UPDATE IS NECESSARY TO ALTER EARLY MORNING POPS WORDING...AND REFOCUS ATTENTION ON THIS AFTERNOON'S CONVECTION AND NEAR RECORD TEMPS. .KHGX...NONE. 31/47 UPDATED PRELIMS... CLL BB 087/055 081/057 076 400 IAH BB 088/057 083/058 078 300 GLS BB 081/064 077/064 075 200 INCREASED TODAY'S HIGH 3F tx