AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TALLAHASSEE FL 800 PM EDT THU APR 10 2003 CURRENTLY: CLOUDY WITH PATCHY LIGHT RAIN OR SPRINKLES. CIGS GENLLY AROUND 3K AND 10K BUT LOWER CIGS TO 1K STRATOCU WITH LIGHT FOG UNDER PATCHY RAIN. TEMPS RANGING FROM THE MID 40S SE ALA TO MID 50S PANHANDLE COAST. DEW POINTS LOW TO MID 50S. WINDS NW TO W 10 TO 15 MPH. DISCUSSION: TIGHT UPR LOW CONTS TO MEANDER OVR S CAROLINA WITH MOISTURE ROTATING AROUND AND S TOWARDS CWFA. HOWEVER WITH LOCAL AREA ON DRY/SUBSIDENCE SIDE...MOISTURE FIELD IS WEAK. THUS LOW MEANDERING WITH VORT LOBE EXTENDING S RATHER THAN LIFTING AS PREV PROGGED PROVIDG JUST ENUF LIFT TO MAINTAIN CLOUDY SKIES AND LINGERING RAIN LITTLE LONGER THAN PREV FORECASTED. FIRST LOBE TO EXIT E SHORTLY BUT MESO-ETA AND RUC HINT AT ANOTHER AND FINAL LOBE MOVING THRU DURING PREDAWN HOURS. THEN...EXPECT LOW TO FINALLY MOVE NWD BY TOMORROW MORNING SPREADING SOAKING RAINS INTO MID-ATLC AND THEN N ENGLAND STATES. CLOSER TO HOME...THIS TRANLATES TO DECRG CLOUDS AND PRECIP BY SUNRISE. WILL UPDATE TO CHANGE MOSTLY CLOUDY AND NIGHTTIME POPS TO CLOUDY AND 20 PCT LIGHT RAIN OR SPRINKLES EXCEPT M/CLOUDY AND 10 PCT PANHANDLE. TEMPS LOOK REASONABLE EXCEPT POSSIBLY SE ALA ALREADY APPROACHING INHERITED LOW SO MAY TWEK DOWN A FEW DEGREES. MARINE: WITH COLD AIR ADVECTION RAPIDLY FILTERING S AND ACROSS LOCAL WATERS...EVENING BUOYS SHOW 15 TO 20 KNOTS NEARSHORE UP TO 20-25 KNOTS WITH GUSTS TO 35 KT AND 10-11 FOOT SEAS WELL OFFSHORE. THIS MESHES WELL WITH INHERITED FORECAST SO EXPECT NO CHANGES. COLD AIR ADVECTION FORECASTED TO DECR SOME BY SUNRISE SO WINDS.SEAS SHOULD BEGIN TO SLOWLY LOWER BUT SCA LOOKS GOOD INTO SATURDAY. .TLH... AL...NONE. GA...NONE. FL...SMALL CRAFT ADVISORY ALL MARINE ZONES. $$ BLOCK ___________________________________________________________________ PREVIOUS DISCUSSION --SYNOPSIS-- WATER VAPOR IMAGES SHOW NEARLY STATIONARY UPPER LOW SPINNING OVER THE GA/SC BORDER. A VORT LOBE IS ROTATING AROUND THE WRN QUAD AND GENERATING SOME RAIN OVER N-CENTRAL GA AND AL. FARTHER UPSTREAM... W/V IMAGES INDICATE SHORTWAVE RIDGING OVER OVER THE PLAINS. SURFACE LOW IS CENTERED NEAR WILMINGTON NC. WINDS OVER THE CWFA REMAIN FAIRLY HIGH DUE TO THE LOCALLY TIGHT PRESSURE GRADIENT. --FORECAST-- TONIGHT...MAY SEE A FEW SPRINKLES OVER NRN ZONES DUE TO MENTIONED VORT LOBE. AFTERWARDS...FRIDAY AND SATURDAY LOOKING DRY AS SURFACE LOW MOVES RAPIDLY UP THE E COAST AND THE UPPER LOW OPENS INTO A PROGRESSIVE TROUGH THAT BRINGS A SURFACE RIDGE TOWARDS OUR CWFA. FIRE WEATHER...WE SHOULD SEE MARGINAL DURATIONS OF LOW RH VALUES OVER FL ZONES FRIDAY...AND THEY COULD BE ACCOMPANIED BY 20 FT WINDS NEAR 15 MPH. HOWEVER...THIS IS ASSUMING QUITE LOW GUIDANCE DEWPOINT THAT MAY HAVE A TOUGH TIME BEING REALIZED GIVEN THE WET GROUND FROM RECENT RAINS. WILL NOT ISSUE ANY WATCHES OR WARNINGS AT THIS TIME. MARINE...EXPECT WINDS TO INCREASE TO SCA TONIGHT. SCA CONDITIONS MAY WELL CONTINUE INTO SATURDAY MORNING...WHEN SURFACE HIGH PRESSURE APPROACHES THE CWFA. EXTENDED (SUNDAY-THURSDAY)...AS UPPER RIDGE TRANSLATES E INTO THE ERN USA...10/06Z GFS PUSHES REINFORCING FRONT S INTO THE CWFA AND GENERATES SOME PRECIP. LATEST GFS SUGGESTS SOME PRECIP MAY BE POSSIBLE SUNDAY AND MONDAY AFTERNOONS AHEAD OF AND ALONG THIS FRONT. WILL NOT JUMP ON THIS YET...AS WE EXPECT A RATHER DRY LOWER TROPOSPHERE DURING THIS TIME. TUESDAY LOOKS MORE CERTAINLY FREE OF SENSIBLE WEATHER WITH AN UPPER SHORTWAVE RIDGE WORKING E INTO THE CWFA. HAVE INSERTED A SLIGHT CHANCE OF POPS OVER WED AND THU OVER WRN ZONES...WHERE GFS PROGS BETTER MOIST RETURN AND EVIDENCE OF A BOUNDARY LIFTING N. PRELIMINARY NUMBERS... TLH 043/074 046/078 0000 PFN 047/072 052/079 0000 DHN 044/072 049/077 2000 ABY 043/072 048/077 2000 VLD 045/073 047/079 0000 CTY 043/069 047/077 0000 .TLH... AL...NONE. GA...NONE. FL...SMALL CRAFT ADVISORY ALL MARINE ZONES. $$ TJT PREVIOUS DISCUSSION FOLLOWS. *********************************************************** 948 AM EDT THU APR 10 2003 UPPER LOW CURRENTLY SPINNING OVER CENTRAL GA. 12Z KTLH SOUNDING SHOWED 500 MB TEMPS DOWN AROUND -24 C. THIS LOW WILL MIGRATE ONLY VERY SLOWLY EWD TO A POSITION OVER CENTRAL SC BY 00Z. WATER VAPOR IMAGERY AND RUC ANALYSES SHOW ONE VORT MAX APPROACHING THE CAROLINA COAST FROM THE SSW WITH ANOTHER PIVOTING SWWD ON THE W SIDE OF THE VORTEX ALONG THE AL/MS BORDER. THE VERY DRY MID AND UPPER LEVEL AIR HAS MOVED E AND S OF THE AREA WITH MOISTURE WRAPPING BACK AROUND THE N AND W SIDE OF THE SYSTEM. VISIBLE SATELLITE PIX SHOW A NEARLY UNBROKEN DECK OF STRATUS CLOUDS WITH BASES BELOW 2 KFT. THE SURFACE LOW ABOUT 60 MI SSE OF CAPE FEAR NC. SURFACE HIGH PRESSURE IS CENTERED IN THE PLAINS. IN BETWEEN, A 6 MB PRESSURE GRADIENT EXISTS ACROSS THE CWFA. WINDS STAYED UP THROUGH THE NIGHT AND ARE CURRENTLY GUSTING TO 20 MPH AT A FEW METAR SITES IN THE PANHANDLE AND GA. 12Z KTLH SOUNDING SHOWS AN INVERSION AT ABOUT 850 MB. MODEL SOUNDING SHOW THIS INVERSION HANGING IN THERE MOST OF THE DAY WITH MIXING HEIGHTS ONLY AROUND 25 KFT OR LESS. CLOUDS WILL REMAIN TRAPPED BENEATH THIS INVERSION. WINDS IN THE MIXING LAYER LOOK TO GET NO HIGHER THAN 25 KT. THEREFORE, DO NOT EXPECT TO MEET WIND ADVISORY CRITERIA TODAY. WILL HOWEVER INSERT STATEMENT INTO THE ZONES ADVISING CAUTION ON AREA LAKES. CLOUDS AND COLD ADVECTION WILL KEEP AFTERNOON TEMPS A GOOD 20 DEGREES BELOW SEASONAL NORMS. ONLY MINOR ADJUSTMENT WILL BE NEEDED TO TEMPS. 12Z SOUNDING SHOWED PW DOWN AROUND A HALF AN INCH, SO THERE IS NOT A LOT OF MOISTURE AVAILABLE FOR PRECIP. LOOKING FOR MAINLY CLOUDS WITH A FEW SPRINKLES ACROSS MOST OF THE CWFA. WILL ALLOW FOR LOW CHANCE POPS IN GA ZONES, CLOSER TO COLD CORE LOW AND STEEPEST LAPSE RATES. MARINE: ISSUED AN EARLY UPDATE TO BRING SEAS FORECAST IN LINE WITH OBSERVATIONS. BOTH BUOYS HAVE BEEN SHOWING NEARLY 11 FOOT SEAS, WHICH IS CLOSE TO WAVEWATCH AND WHAT YOU WOULD EXPECT WITH 20-25 KT NW WINDS. SCA STILL LOOKS LIKE IT WILL PERSIST THROUGH TONIGHT. WAVEWATCH SHOWS ENVELOP OF MAXIMUM SEAS SHIFTING SLIGHTLY SEWD TONIGHT, DESPITE RELATIVELY CONSTANT WIND SPEEDS. .TLH... AL...CAUTION ADVISED ON AREA LAKES. GA...CAUTION ADVISED ON AREA LAKES. FL...SMALL CRAFT ADVISORY ALL MARINE ZONES. CAUTION ADVISED ON AREA LAKES. WOOL PREVIOUS DISCUSSION FOLLOWS. ***************************************************************** 235 AM EDT THU APR 10 2003 CURRENTLY: AS THE SURFACE LOW PUSHES NE OFF THE CAROLINA COAST WRAPAROUND MOISTURE IS KEEPING THE SKIES CLOUDY. TEMPERATURES ARE IN THE UPPER 40S...NEARLY 10 DEGREES COLDER THAN SAME TIME YESTERDAY... WITH NW WINDS GUSTING TO 25. OFF SHORE WINDS ARE EVEN HIGHER...NW AT 25G35 WITH 10 FEET SEAS. PRESSURE GRADIENT SHOWS NO SIGNS OF RELAXING...MAY EVEN TIGHTEN A BIT OVER THE NEXT 12 TO 18 HOURS PANHANDLE/ALABAMA AND KEEPING WINDS UP IN MOST AREAS WITH GUSTS. AREA RADARS ARE SHOWING LIGHT RAIN OVER NORTHERN AND EASTERN ZONES. SHORT RANGE MODELS CONTINUE IN GOOD AGREEMENT AND SHOW THE UPPER LOW OVER THE SOUTHERN AL/GA BORDER WILL MOVE NE ALONG THE EAST COAST...OVER HATTERAS AND OUT INTO THE ATLANTIC BY EARLY SATURDAY... SUSTAINING ITS CURRENT STRENGTH AS IT TRAVELS. THE SFC LOW WILL ALSO MOVE NE...WEAKENING SOMEWHAT AS IT DOES SO. ONE CONCERN FOR OUR CWA IS HOW MUCH WRAP AROUND MOISTURE WILL MAKE IT BACK OVER OUR AREA. MODELS DIFFER ON HOW MUCH WHIPLASH TO APPLY AND HOW FAR WEST AND SOUTH TO BRING THE LOW...WITH THE DYNAMIC ETA BRINGING THE LOW ALL THE BACK INTO GA...ACCOMPANIED BY MORE MOISTURE FARTHER SOUTH. TYPICALLY WETTER FWC AND ETA STILL CALL FOR HIGHER POPS TODAY ACROSS THE BOARD THAN ANY OF THE OTHER MODELS...20 TO 30 PERCENT HIGHER THAN THE VERY DRY MAV. HAVE GONE WITH MODIFIED MAV. EXPECT MOST OF THE PRECIP TOMORROW TO BE OF A SHOWERY AND GENERALLY LIGHT NATURE. THURSDAY WILL PROVE TO BE A MOSTLY CLOUDY...BLUSTERY...AND VERY COOL DAY ACROSS THE REGION...THE BLACKBERRY WINTER OF FOLKLORE. LOW FINALLY HEADS NE UP THE E SEABOARD ON THURSDAY NIGHT...EXPECT IMPROVING CONDITIONS ACROSS THE CWA WITH A FAIR...COOL...AND DRY DAY FOR FRIDAY. LITTLE CHANGE TO TEMP FORECAST FROM PREVIOUS RUN. AGAIN...THE TEMP FORECAST LEANS TOWARD MAV GUIDANCE. MARINE: WINDS AND SEAS WILL STAY AT SCA OR SCEC CONDITIONS FOR THE NEXT 24 TO 36 HOURS...LASTING INTO FRIDAY EVENING...FINALLY GOING BELOW SCEC CONDITIONS ON SATURDAY. FIRE WX: NO CONCERNS THROUGH SATURDAY...ALTHOUGH RH VALUES MAY DROP BELOW 40 PERCENT ON SATURDAY. EXTENDED: LITTLE CHANGE TO EXTENDED FORECAST. EXPECT A STRETCH OF FAIR AND DRY WEATHER...AS WEAK SFC RIDGING AND DRY NW FLOW ALOFT DOMINATE CONDITIONS. LOOK FOR THE NEXT COLD FRONT AND CHANCE FOR ANY PRECIPITATION TO COME IN LATE WEDNESDAY INTO EARLY THURSDAY. THUS WILL SHOW INCREASING CLOUDS FOR WEDNESDAY IN THE EXTENDED FORECAST. TLH 59 43 72 45 78 2100 PFN 60 46 71 52 76 1100 DHN 54 44 70 49 77 2100 ABY 55 43 70 48 77 2100 VLD 57 46 70 48 78 2100 CTY 60 46 68 47 78 1100 $$ AFD fl AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TALLAHASSEE FL 300 PM EDT THU APR 10 2003 --SYNOPSIS-- WATER VAPOR IMAGES SHOW NEARLY STATIONARY UPPER LOW SPINNING OVER THE GA/SC BORDER. A VORT LOBE IS ROTATING AROUND THE WRN QUAD AND GENERATING SOME RAIN OVER N-CENTRAL GA AND AL. FARTHER UPSTREAM... W/V IMAGES INDICATE SHORTWAVE RIDGING OVER OVER THE PLAINS. SURFACE LOW IS CENTERED NEAR WILMINGTON NC. WINDS OVER THE CWFA REMAIN FAIRLY HIGH DUE TO THE LOCALLY TIGHT PRESSURE GRADIENT. --FORECAST-- TONIGHT...MAY SEE A FEW SPRINKLES OVER NRN ZONES DUE TO MENTIONED VORT LOBE. AFTERWARDS...FRIDAY AND SATURDAY LOOKING DRY AS SURFACE LOW MOVES RAPIDLY UP THE E COAST AND THE UPPER LOW OPENS INTO A PROGRESSIVE TROUGH THAT BRINGS A SURFACE RIDGE TOWARDS OUR CWFA. FIRE WEATHER...WE SHOULD SEE MARGINAL DURATIONS OF LOW RH VALUES OVER FL ZONES FRIDAY...AND THEY COULD BE ACCOMPANIED BY 20 FT WINDS NEAR 15 MPH. HOWEVER...THIS IS ASSUMING QUITE LOW GUIDANCE DEWPOINT THAT MAY HAVE A TOUGH TIME BEING REALIZED GIVEN THE WET GROUND FROM RECENT RAINS. WILL NOT ISSUE ANY WATCHES OR WARNINGS AT THIS TIME. MARINE...EXPECT WINDS TO INCREASE TO SCA TONIGHT. SCA CONDITIONS MAY WELL CONTINUE INTO SATURDAY MORNING...WHEN SURFACE HIGH PRESSURE APPROACHES THE CWFA. EXTENDED (SUNDAY-THURSDAY)...AS UPPER RIDGE TRANSLATES E INTO THE ERN USA...10/06Z GFS PUSHES REINFORCING FRONT S INTO THE CWFA AND GENERATES SOME PRECIP. LATEST GFS SUGGESTS SOME PRECIP MAY BE POSSIBLE SUNDAY AND MONDAY AFTERNOONS AHEAD OF AND ALONG THIS FRONT. WILL NOT JUMP ON THIS YET...AS WE EXPECT A RATHER DRY LOWER TROPOSPHERE DURING THIS TIME. TUESDAY LOOKS MORE CERTAINLY FREE OF SENSIBLE WEATHER WITH AN UPPER SHORTWAVE RIDGE WORKING E INTO THE CWFA. HAVE INSERTED A SLIGHT CHANCE OF POPS OVER WED AND THU OVER WRN ZONES...WHERE GFS PROGS BETTER MOIST RETURN AND EVIDENCE OF A BOUNDARY LIFTING N. PRELIMINARY NUMBERS... TLH 043/074 046/078 0000 PFN 047/072 052/079 0000 DHN 044/072 049/077 2000 ABY 043/072 048/077 2000 VLD 045/073 047/079 0000 CTY 043/069 047/077 0000 .TLH... AL...NONE. GA...NONE. FL...SMALL CRAFT ADVISORY ALL MARINE ZONES. $$ TJT PREVIOUS DISCUSSION FOLLOWS. *********************************************************** 948 AM EDT THU APR 10 2003 UPPER LOW CURRENTLY SPINNING OVER CENTRAL GA. 12Z KTLH SOUNDING SHOWED 500 MB TEMPS DOWN AROUND -24 C. THIS LOW WILL MIGRATE ONLY VERY SLOWLY EWD TO A POSITION OVER CENTRAL SC BY 00Z. WATER VAPOR IMAGERY AND RUC ANALYSES SHOW ONE VORT MAX APPROACHING THE CAROLINA COAST FROM THE SSW WITH ANOTHER PIVOTING SWWD ON THE W SIDE OF THE VORTEX ALONG THE AL/MS BORDER. THE VERY DRY MID AND UPPER LEVEL AIR HAS MOVED E AND S OF THE AREA WITH MOISTURE WRAPPING BACK AROUND THE N AND W SIDE OF THE SYSTEM. VISIBLE SATELLITE PIX SHOW A NEARLY UNBROKEN DECK OF STRATUS CLOUDS WITH BASES BELOW 2 KFT. THE SURFACE LOW ABOUT 60 MI SSE OF CAPE FEAR NC. SURFACE HIGH PRESSURE IS CENTERED IN THE PLAINS. IN BETWEEN, A 6 MB PRESSURE GRADIENT EXISTS ACROSS THE CWFA. WINDS STAYED UP THROUGH THE NIGHT AND ARE CURRENTLY GUSTING TO 20 MPH AT A FEW METAR SITES IN THE PANHANDLE AND GA. 12Z KTLH SOUNDING SHOWS AN INVERSION AT ABOUT 850 MB. MODEL SOUNDING SHOW THIS INVERSION HANGING IN THERE MOST OF THE DAY WITH MIXING HEIGHTS ONLY AROUND 25 KFT OR LESS. CLOUDS WILL REMAIN TRAPPED BENEATH THIS INVERSION. WINDS IN THE MIXING LAYER LOOK TO GET NO HIGHER THAN 25 KT. THEREFORE, DO NOT EXPECT TO MEET WIND ADVISORY CRITERIA TODAY. WILL HOWEVER INSERT STATEMENT INTO THE ZONES ADVISING CAUTION ON AREA LAKES. CLOUDS AND COLD ADVECTION WILL KEEP AFTERNOON TEMPS A GOOD 20 DEGREES BELOW SEASONAL NORMS. ONLY MINOR ADJUSTMENT WILL BE NEEDED TO TEMPS. 12Z SOUNDING SHOWED PW DOWN AROUND A HALF AN INCH, SO THERE IS NOT A LOT OF MOISTURE AVAILABLE FOR PRECIP. LOOKING FOR MAINLY CLOUDS WITH A FEW SPRINKLES ACROSS MOST OF THE CWFA. WILL ALLOW FOR LOW CHANCE POPS IN GA ZONES, CLOSER TO COLD CORE LOW AND STEEPEST LAPSE RATES. MARINE: ISSUED AN EARLY UPDATE TO BRING SEAS FORECAST IN LINE WITH OBSERVATIONS. BOTH BUOYS HAVE BEEN SHOWING NEARLY 11 FOOT SEAS, WHICH IS CLOSE TO WAVEWATCH AND WHAT YOU WOULD EXPECT WITH 20-25 KT NW WINDS. SCA STILL LOOKS LIKE IT WILL PERSIST THROUGH TONIGHT. WAVEWATCH SHOWS ENVELOP OF MAXIMUM SEAS SHIFTING SLIGHTLY SEWD TONIGHT, DESPITE RELATIVELY CONSTANT WIND SPEEDS. .TLH... AL...CAUTION ADVISED ON AREA LAKES. GA...CAUTION ADVISED ON AREA LAKES. FL...SMALL CRAFT ADVISORY ALL MARINE ZONES. CAUTION ADVISED ON AREA LAKES. WOOL PREVIOUS DISCUSSION FOLLOWS. ***************************************************************** 235 AM EDT THU APR 10 2003 CURRENTLY: AS THE SURFACE LOW PUSHES NE OFF THE CAROLINA COAST WRAPAROUND MOISTURE IS KEEPING THE SKIES CLOUDY. TEMPERATURES ARE IN THE UPPER 40S...NEARLY 10 DEGREES COLDER THAN SAME TIME YESTERDAY... WITH NW WINDS GUSTING TO 25. OFF SHORE WINDS ARE EVEN HIGHER...NW AT 25G35 WITH 10 FEET SEAS. PRESSURE GRADIENT SHOWS NO SIGNS OF RELAXING...MAY EVEN TIGHTEN A BIT OVER THE NEXT 12 TO 18 HOURS PANHANDLE/ALABAMA AND KEEPING WINDS UP IN MOST AREAS WITH GUSTS. AREA RADARS ARE SHOWING LIGHT RAIN OVER NORTHERN AND EASTERN ZONES. SHORT RANGE MODELS CONTINUE IN GOOD AGREEMENT AND SHOW THE UPPER LOW OVER THE SOUTHERN AL/GA BORDER WILL MOVE NE ALONG THE EAST COAST...OVER HATTERAS AND OUT INTO THE ATLANTIC BY EARLY SATURDAY... SUSTAINING ITS CURRENT STRENGTH AS IT TRAVELS. THE SFC LOW WILL ALSO MOVE NE...WEAKENING SOMEWHAT AS IT DOES SO. ONE CONCERN FOR OUR CWA IS HOW MUCH WRAP AROUND MOISTURE WILL MAKE IT BACK OVER OUR AREA. MODELS DIFFER ON HOW MUCH WHIPLASH TO APPLY AND HOW FAR WEST AND SOUTH TO BRING THE LOW...WITH THE DYNAMIC ETA BRINGING THE LOW ALL THE BACK INTO GA...ACCOMPANIED BY MORE MOISTURE FARTHER SOUTH. TYPICALLY WETTER FWC AND ETA STILL CALL FOR HIGHER POPS TODAY ACROSS THE BOARD THAN ANY OF THE OTHER MODELS...20 TO 30 PERCENT HIGHER THAN THE VERY DRY MAV. HAVE GONE WITH MODIFIED MAV. EXPECT MOST OF THE PRECIP TOMORROW TO BE OF A SHOWERY AND GENERALLY LIGHT NATURE. THURSDAY WILL PROVE TO BE A MOSTLY CLOUDY...BLUSTERY...AND VERY COOL DAY ACROSS THE REGION...THE BLACKBERRY WINTER OF FOLKLORE. LOW FINALLY HEADS NE UP THE E SEABOARD ON THURSDAY NIGHT...EXPECT IMPROVING CONDITIONS ACROSS THE CWA WITH A FAIR...COOL...AND DRY DAY FOR FRIDAY. LITTLE CHANGE TO TEMP FORECAST FROM PREVIOUS RUN. AGAIN...THE TEMP FORECAST LEANS TOWARD MAV GUIDANCE. MARINE: WINDS AND SEAS WILL STAY AT SCA OR SCEC CONDITIONS FOR THE NEXT 24 TO 36 HOURS...LASTING INTO FRIDAY EVENING...FINALLY GOING BELOW SCEC CONDITIONS ON SATURDAY. FIRE WX: NO CONCERNS THROUGH SATURDAY...ALTHOUGH RH VALUES MAY DROP BELOW 40 PERCENT ON SATURDAY. EXTENDED: LITTLE CHANGE TO EXTENDED FORECAST. EXPECT A STRETCH OF FAIR AND DRY WEATHER...AS WEAK SFC RIDGING AND DRY NW FLOW ALOFT DOMINATE CONDITIONS. LOOK FOR THE NEXT COLD FRONT AND CHANCE FOR ANY PRECIPITATION TO COME IN LATE WEDNESDAY INTO EARLY THURSDAY. THUS WILL SHOW INCREASING CLOUDS FOR WEDNESDAY IN THE EXTENDED FORECAST. TLH 59 43 72 45 78 2100 PFN 60 46 71 52 76 1100 DHN 54 44 70 49 77 2100 ABY 55 43 70 48 77 2100 VLD 57 46 70 48 78 2100 CTY 60 46 68 47 78 1100 $$ AFD fl AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TALLAHASSEE FL 948 AM EDT THU APR 10 2003 UPPER LOW CURRENTLY SPINNING OVER CENTRAL GA. 12Z KTLH SOUNDING SHOWED 500 MB TEMPS DOWN AROUND -24 C. THIS LOW WILL MIGRATE ONLY VERY SLOWLY EWD TO A POSITION OVER CENTRAL SC BY 00Z. WATER VAPOR IMAGERY AND RUC ANALYSES SHOW ONE VORT MAX APPROACHING THE CAROLINA COAST FROM THE SSW WITH ANOTHER PIVOTING SWWD ON THE W SIDE OF THE VORTEX ALONG THE AL/MS BORDER. THE VERY DRY MID AND UPPER LEVEL AIR HAS MOVED E AND S OF THE AREA WITH MOISTURE WRAPPING BACK AROUND THE N AND W SIDE OF THE SYSTEM. VISIBLE SATELLITE PIX SHOW A NEARLY UNBROKEN DECK OF STRATUS CLOUDS WITH BASES BELOW 2 KFT. THE SURFACE LOW ABOUT 60 MI SSE OF CAPE FEAR NC. SURFACE HIGH PRESSURE IS CENTERED IN THE PLAINS. IN BETWEEN, A 6 MB PRESSURE GRADIENT EXISTS ACROSS THE CWFA. WINDS STAYED UP THROUGH THE NIGHT AND ARE CURRENTLY GUSTING TO 20 MPH AT A FEW METAR SITES IN THE PANHANDLE AND GA. 12Z KTLH SOUNDING SHOWS AN INVERSION AT ABOUT 850 MB. MODEL SOUNDING SHOW THIS INVERSION HANGING IN THERE MOST OF THE DAY WITH MIXING HEIGHTS ONLY AROUND 25 KFT OR LESS. CLOUDS WILL REMAIN TRAPPED BENEATH THIS INVERSION. WINDS IN THE MIXING LAYER LOOK TO GET NO HIGHER THAN 25 KT. THEREFORE, DO NOT EXPECT TO MEET WIND ADVISORY CRITERIA TODAY. WILL HOWEVER INSERT STATEMENT INTO THE ZONES ADVISING CAUTION ON AREA LAKES. CLOUDS AND COLD ADVECTION WILL KEEP AFTERNOON TEMPS A GOOD 20 DEGREES BELOW SEASONAL NORMS. ONLY MINOR ADJUSTMENT WILL BE NEEDED TO TEMPS. 12Z SOUNDING SHOWED PW DOWN AROUND A HALF AN INCH, SO THERE IS NOT A LOT OF MOISTURE AVAILABLE FOR PRECIP. LOOKING FOR MAINLY CLOUDS WITH A FEW SPRINKLES ACROSS MOST OF THE CWFA. WILL ALLOW FOR LOW CHANCE POPS IN GA ZONES, CLOSER TO COLD CORE LOW AND STEEPEST LAPSE RATES. MARINE: ISSUED AN EARLY UPDATE TO BRING SEAS FORECAST IN LINE WITH OBSERVATIONS. BOTH BUOYS HAVE BEEN SHOWING NEARLY 11 FOOT SEAS, WHICH IS CLOSE TO WAVEWATCH AND WHAT YOU WOULD EXPECT WITH 20-25 KT NW WINDS. SCA STILL LOOKS LIKE IT WILL PERSIST THROUGH TONIGHT. WAVEWATCH SHOWS ENVELOP OF MAXIMUM SEAS SHIFTING SLIGHTLY SEWD TONIGHT, DESPITE RELATIVELY CONSTANT WIND SPEEDS. .TLH... AL...CAUTION ADVISED ON AREA LAKES. GA...CAUTION ADVISED ON AREA LAKES. FL...SMALL CRAFT ADVISORY ALL MARINE ZONES. CAUTION ADVISED ON AREA LAKES. WOOL PREVIOUS DISCUSSION FOLLOWS. ***************************************************************** 235 AM EDT THU APR 10 2003 CURRENTLY: AS THE SURFACE LOW PUSHES NE OFF THE CAROLINA COAST WRAPAROUND MOISTURE IS KEEPING THE SKIES CLOUDY. TEMPERATURES ARE IN THE UPPER 40S...NEARLY 10 DEGREES COLDER THAN SAME TIME YESTERDAY... WITH NW WINDS GUSTING TO 25. OFF SHORE WINDS ARE EVEN HIGHER...NW AT 25G35 WITH 10 FEET SEAS. PRESSURE GRADIENT SHOWS NO SIGNS OF RELAXING...MAY EVEN TIGHTEN A BIT OVER THE NEXT 12 TO 18 HOURS PANHANDLE/ALABAMA AND KEEPING WINDS UP IN MOST AREAS WITH GUSTS. AREA RADARS ARE SHOWING LIGHT RAIN OVER NORTHERN AND EASTERN ZONES. SHORT RANGE MODELS CONTINUE IN GOOD AGREEMENT AND SHOW THE UPPER LOW OVER THE SOUTHERN AL/GA BORDER WILL MOVE NE ALONG THE EAST COAST...OVER HATTERAS AND OUT INTO THE ATLANTIC BY EARLY SATURDAY... SUSTAINING ITS CURRENT STRENGTH AS IT TRAVELS. THE SFC LOW WILL ALSO MOVE NE...WEAKENING SOMEWHAT AS IT DOES SO. ONE CONCERN FOR OUR CWA IS HOW MUCH WRAP AROUND MOISTURE WILL MAKE IT BACK OVER OUR AREA. MODELS DIFFER ON HOW MUCH WHIPLASH TO APPLY AND HOW FAR WEST AND SOUTH TO BRING THE LOW...WITH THE DYNAMIC ETA BRINGING THE LOW ALL THE BACK INTO GA...ACCOMPANIED BY MORE MOISTURE FARTHER SOUTH. TYPICALLY WETTER FWC AND ETA STILL CALL FOR HIGHER POPS TODAY ACROSS THE BOARD THAN ANY OF THE OTHER MODELS...20 TO 30 PERCENT HIGHER THAN THE VERY DRY MAV. HAVE GONE WITH MODIFIED MAV. EXPECT MOST OF THE PRECIP TOMORROW TO BE OF A SHOWERY AND GENERALLY LIGHT NATURE. THURSDAY WILL PROVE TO BE A MOSTLY CLOUDY...BLUSTERY...AND VERY COOL DAY ACROSS THE REGION...THE BLACKBERRY WINTER OF FOLKLORE. LOW FINALLY HEADS NE UP THE E SEABOARD ON THURSDAY NIGHT...EXPECT IMPROVING CONDITIONS ACROSS THE CWA WITH A FAIR...COOL...AND DRY DAY FOR FRIDAY. LITTLE CHANGE TO TEMP FORECAST FROM PREVIOUS RUN. AGAIN...THE TEMP FORECAST LEANS TOWARD MAV GUIDANCE. MARINE: WINDS AND SEAS WILL STAY AT SCA OR SCEC CONDITIONS FOR THE NEXT 24 TO 36 HOURS...LASTING INTO FRIDAY EVENING...FINALLY GOING BELOW SCEC CONDITIONS ON SATURDAY. FIRE WX: NO CONCERNS THROUGH SATURDAY...ALTHOUGH RH VALUES MAY DROP BELOW 40 PERCENT ON SATURDAY. EXTENDED: LITTLE CHANGE TO EXTENDED FORECAST. EXPECT A STRETCH OF FAIR AND DRY WEATHER...AS WEAK SFC RIDGING AND DRY NW FLOW ALOFT DOMINATE CONDITIONS. LOOK FOR THE NEXT COLD FRONT AND CHANCE FOR ANY PRECIPITATION TO COME IN LATE WEDNESDAY INTO EARLY THURSDAY. THUS WILL SHOW INCREASING CLOUDS FOR WEDNESDAY IN THE EXTENDED FORECAST. TLH 59 43 72 45 78 2100 PFN 60 46 71 52 76 1100 DHN 54 44 70 49 77 2100 ABY 55 43 70 48 77 2100 VLD 57 46 70 48 78 2100 CTY 60 46 68 47 78 1100 $$ AFD fl AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 1002 PM EDT THU APR 10 2003 WV LOOP/RUC ANALYSIS SHOWS WELL DEFINED SHRTWV/CLOSED LOW MOVG TOWARD HUDSON BAY. WK TROF EXTENDING FM HUDSON BAY SFC LOW HAS MOVED THRU MN AND INTO WRN LAKE SUPERIOR. THIS WK TROF WL MOVE THRU THE FORECAST AREA OVRNGT AS LIGHT WINDS SHIFT FM SSW TO W. OTHER THAN WIND SHIFT...NOT MUCH HAPPENING AS CIRRUS CLDS ALG BOUNDARY WL BE MINIMAL. LOOK FOR SKIES TO REMAIN MOSTLY CLR OVRNGT. TEMPS STILL LOOK ON TARGET MOST LOCATIONS. DID LOWER MINS A FEW DEGREES (TO AROUND 30) ALONG LAKE MI COUNTIES AS TEMPS THERE ALREADY IN MID TO UPPER 30S WITHIN PAST HR. OTHERWISE...NO OTHER UPDATES NEEDED. .MQT...NONE. VOSS mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON NC 940 PM EDT THU APR 10 2003 LATEST MODEL GUIDANCE SUGGESTS THAT THE NEXT SLUG OF OMEGA ROTATING AROUND THE UPPER LOW WILL ARRIVE OVER THE AREA AROUND 12Z. PLAN TO UPDATE THE ZFP TO LOWER POPS TO THE CHANCE CATEGORY FOR THE REMAINDER OF TONIGHT WITH THE HIGHEST NUMBERS OVER THE SOUTH AND WEST. SKIES WILL NEED SOME ADJUSTMENT TOO WITH COASTAL NC COUNTIES UNDER CLEAR SKIES PRESENTLY. PLAN TO INITIALIZE WITH A GRADIENT IN CLOUDS ACROSS THE AREA. TEMPERATURES WILL BE TWEAKED AFTER A LOOK AT THE 10 PM OBSERVATIONS. MARINE: CURRENTLY SEEING W/SW WINDS 15-20 KT OFFSHORE AND 5-10 KT AT THE BEACHES. WIND FIELDS WILL REMAIN RELATIVELY LIGHT OVERNIGHT. SEAS HAVE BEEN CHURNED UP BY THE STRONG NE FLOW FOR MOST OF THIS WEEK AND WILL ONLY SLOWLY SUBSIDE OVERNIGHT. AS THE LAST LOW PRESSURE FORMS LATE TONIGHT OFF THE SOUTH CAROLINA COAST...WINDS WILL BECOME DIRECTED INTO THE CENTER OF THE LOW TOWARD MORNING. WILL INDICATE DIRECTION BECOMING W IN THE SOUTH CAROLINA WATERS AND NW IN THE NORTH CAROLINA WATERS LATE...IN LINE WITH THE 21Z RUC...18Z ETA...AND 18Z GFS MODELS. AFTER COORD WITH CHS...WILL LEAVE THE SMALL CRAFT ADVISORY UP FOR SEAS FOR ALL WATERS. .ILM... .NC...SMALL CRAFT ADVISORY SURF CITY TO LITTLE RIVER INLET. .SC...SMALL CRAFT ADVISORY LITTLE RIVER INLET TO S SANTEE RIVER. PUBLIC: RAN MARINE: TRA ---------------------PREVIOUS DISCUSSION 404 PM --------------------- THE UPPER LEVEL LOW OVER CENTRAL SC IS CLEARLY VISIBLE ON SATELLITE IMAGERY THIS AFTERNOON. AT THE SURFACE...MSAS ANALYSIS SHOWS THAT THE LOW HAS MOVED INLAND...WITH SW WINDS IN PLACE EVERYWHERE EXCEPT OUR EXTREME NWRN ZONES. WILL ALLOW THE WIND ADVISORY FOR THE NC BEACHES TO EXPIRE. THE BEST THETA-E ADVECTION HAS SHIFTED N OF THE AREA THIS AFTERNOON...TAKING THE PRECIPITATION WHICH AFFECTED THE AREA EARLIER TODAY WITH IT. ALTHOUGH SOME SOME DRIER AIR HAS BEEN ABLE TO WORK ITS WAY INTO PORTIONS OF OUR NC COUNTIES CAUSING THE CLOUDS TO CLEAR OUT A BIT...SHOWERS HAVE SPREAD BACK INTO SRN/SWRN PORTIONS OF THE CWA IN ASSOCIATION WITH THE UPPER LOW. EXPECT PRECIPITATION COVERAGE TO BE ON THE INCREASE TONIGHT...WITH ISENTROPIC LIFT BEST AFTER MIDNIGHT. WILL ALSO CONTINUE TO CARRY ISOLATED TSTMS. WITH THE AREA IN THE WARM SECTOR...AND VERY COOL TEMPERATURES ALOFT...THE THREAT OF HAIL REMAINS. AFTER SPEAKING WITH SPC...WE AGREED THAT THE BEST POTENTIAL FOR ANY SEVERE WEATHER WOULD BE WHERE SOME CLEARING HAS OCCURRED (NRN ZONES). HOWEVER TIME APPEARS TO BE RUNNING OUT FOR CONVECTION TO DEVELOP WITH CLOUDS GETTING READY TO FILL BACK IN AND SUNSET NOT FAR AWAY. THE SURFACE LOW SHOULD GET PICKED UP BY THE UPPER LOW ON FRI...WITH BOTH SYSTEMS THEN MOVING NE OF THE AREA. THIS WILL ALLOW A DRIER WRLY FLOW TO DEVELOP AT THE SURFACE AND ALOFT. WILL FORECAST PRECIPITATION TO TAPER OFF FROM SW TO NE THROUGH EARLY AFTERNOON. CLOUDS WILL DIMINISH FRI NIGHT...WITH MOSTLY CLEAR SKIES EXPECTED SAT. LOOKS LIKE A WEAK BACKDOOR FRONT WILL MOVE THROUGH EARLY SUN. GFS SHOWS AN ONSHORE FLOW FOR MON AND TUE WITH MOISTURE INCREASING OVER THE AREA. FOR NOW WILL GO WITH PARTLY CLOUDY SKIES BOTH DAYS...WITH A SLIGHT CHANCE FOR SHOWERS/TSTMS TUE AFTERNOON AND EVENING. STILL PLENTY OF TIME FOR ADJUSTMENTS TO BE MADE IF NECESSARY. DURING THE REMAINDER OF THE MEDIUM RANGE...WILL KEEP THE FORECAST DRY. HAVE FOLLOWED THE SIMILAR MEX/GFS ENSEMBLE MEAN TEMPERATURES CLOSELY. MARINE: SFC LOW MAKING FOR A CONVALUTED WIND FCST FOR INITIAL PERIOD AS IT WOBBLES OVERHEAD. EXPECT SW WINDS OVER THE WATERS TONIGHT TO BECOME NW FRI AS THE LOW FINALLY LIFTS NE OF THE AREA. WNW DIRECTION EXPECTED TO PERSIST THROUGH SAT...SHIFTING NE EARLY SUN BEHIND COLD FRONT. WEAKEST GRAD ALONG THE EAST COAST IS OVER THE ILM MARINE ZONES. SPEEDS HAVE SETTLED DOWN BELOW SCA THRESHOLDS AS OF 18Z AND SEAS SHOULD SLOWLY FOLLOW SUIT. WILL CONTINUE THE SCA FOR 6 FT SEAS SRN WATERS TO 8-9 FT N OF LITTLE RIVER. PRES GRAD WILL STRENGHTEN FRI AFTN IN WAKE OF THE SFC LOW AND WINDS WILL PICK BACK UP TO 20 KT OR SO INTO SAT AM. OFFSHORE TRAJECTORY WILL LIMIT SEAS TO 3-5 FT. WINDS BEHIND THE FRONT NOT PROGGED TO BE CLOSE TO SCA LEVELS. SOUTHERLY RETURN FLOW SETS UP MON-TUE AS HI PRES MOVES OFF THE COAST. FCSTID = 36 ILM 46 62 46 71 / 70 70 10 0 LBT 45 59 44 72 / 70 60 10 0 FLO 44 61 45 73 / 70 50 10 0 MYR 46 62 47 71 / 60 60 10 0 .ILM... .NC...SMALL CRAFT ADVISORY SURF CITY TO LITTLE RIVER INLET. .SC...SMALL CRAFT ADVISORY SOUTH SANTEE RIVER TO LITTLE RIVER INLET. PUBLIC: JAQ MARINE: CRM nc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON NC 1020 AM EDT THU APR 10 2003 SATELLITE IMAGERY SHOWING THE CENTER OF THE UPPER LEVEL LOW CURRENTLY POSITIONED NEAR THE GA/SC BORDER. A SHORT WAVE REVOLVING AROUND THIS LOW IS CONTINUING TO PRODUCE SHOWERS AND ISOLATED THUNDERSTORMS. ECHOES HAVE BEEN TRAINING ACROSS CENTRAL PORTIONS OF OUR CWA...AS WELL AS FARTHER S NEAR THE GA/SC BORDER JUST AHEAD OF THE UPPER LOW. ALTHOUGH NO REPORTS OF FLOODING AS OF YET...PLAN ON EXTENDING THE FLOOD WATCH THROUGH THE AFTERNOON SINCE THE UPPER LOW IS STILL APPROACHING. MAY ALSO MAKE A FEW ADJUSTMENTS TO POPS BASED ON COVERAGE OF PRECIPITATION. SOME UNCERTAINTY REMAINS WITH REGARDS TO THE TRACK OF THE SURFACE LOW...CURRENTLY LOCATED JUST SE OF CAPE FEAR ACCORDING TO MSAS. THE ETA HAS THE LOW POSITIONED TO CLOSE TO THE COAST...AND THE GFS TO TOO FAR N. THE RUC SEEMS TO HAVE A BETTER HANDLE ON THINGS...AND SHOWS THE LOW MOVING INLAND JUST N OF THE AREA. BECAUSE OF THIS...WILL NEED TO LOWER FORECAST HIGHS...ESPECIALLY FOR OUR INLAND COUNTIES. ANOTHER ISSUE TO DEAL WITH TODAY IS THE HAIL THREAT. WITH THE UPPER LOW APPROACHING...THERE IS A CONSIDERABLE COLD POOL SPREADING OVER THE AREA WITH H5 TEMPERATURES IN THE -15 TO -20 DEG C RANGE AND WET BULB ZERO HEIGHTS AT 6-9K FT. WE RECEIVED A PEA SIZE HAIL REPORT WITH A VIL LESS THAN 5 EARLIER THIS MORNING. DO NOT PLAN ON ISSUING A SEVERE WEATHER OUTLOOK...BUT WE WILL NEED TO WATCH THIS CLOSELY. MARINE: SFC LOW WAS LOCATED APPROXIMATELY 60 NM SSE OF CAPE FEAR AT 13Z. WINDS AT OR JUST BELOW SCA ATTM ACROSS THE WATERS AND SHOULD DROP OFF AS THE LOW GETS PULLED WESTWARD UNDER THE UPPER LOW. 13Z OBSERVED SEAS 9-10 FT AT FPSN7 AND 41004 SO SCA WILL REMAIN IN PLACE. WILL ADJUST WINDS BASED ON LATEST LOW POSITION. .ILM... .NC...FLOOD WATCH PENDER-NEW HANOVER-BRUNSWICK-BLADEN-COLUMBUS- ROBESON COUNTIES. SMALL CRAFT ADVISORY SURF CITY TO LITTLE RIVER INLET. .SC...FLOOD WATCH HORRY-GEORGETOWN-MARION-WILLIAMSBURG-DILLON- FLORENCE-MARLBORO-DARLINGTON COUNTIES. SMALL CRAFT ADVISORY LITTLE RIVER INLET TO S SANTEE RIVER. PUBLIC: JAQ MARINE: CRM nc SOUTHEAST MICHIGAN AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 325 AM EDT FRI APR 11 2003 00Z RAOBS/WATER VAPOR LOOP SHOW SOUTHERN STREAM LOW OVER THE SOUTHEAST CONUS...WITH NORTHERN STREAM LOW NEAR JAMES BAY. GREAT LAKES SANDWICHED BETWEEN THESE SYSTEMS UNDER UPPER SHORTWAVE RIDGE...FROM LONGWAVE RIDGE OVER THE PLAINS. SURFACE ANALYSIS SHOWS LOWS OFF THE SOUTHEAST COAST AND NEAR HUDSON BAY...WITH NARROW RIDGE ACROSS SOUTHERN LOWER. COLD FRONT FROM THE NORTHERN LOW EXTENDS ACROSS THE NORTHERN GREAT LAKES AND INTO MINNESOTA...WITH SECONDARY FRONT WEST THROUGH LAKE WINNIPEG. IR SATELLITE SHOWS CLEAR SKIES ACROSS SOUTHEAST MICHIGAN...WITH CIRRUS FROM THE SOUTHERN SYSTEM NOT MAKING MUCH PROGRESS PAST LAKE ERIE...AND LITTLE IN THE WAY OF ANY CLOUDS WITH THE FIRST COLD FRONT. QUIET AND DRY FORECAST...WITH ONLY CONCERNS REVOLVING AROUND TEMPERATURES AND CLOUDS. SHORTWAVE OVER WISCONSIN SHARPER ON WATER VAPOR LOOP THAN DEPICTED BY 00Z MODELS...ALTHOUGH THE 03Z RUC HAS TRENDED A BIT STRONGER. SURFACE FRONT NOT THAT IMPRESSIVE...AND WEAKENS FURTHER/SHEARS OUT AS THE MAIN LOW TRACKS EAST THROUGH NORTHERN QUEBEC. NOT MUCH IN THE WAY OF CLOUDS WITH THIS FEATURE...WITH JUST A THIN AND NARROW RIBBON OF CIRRUS ACROSS UPPER MICHIGAN/WISCONSIN. DOWNSTREAM ACROSS SOUTHEAST MICHIGAN SKIES ARE CURRENTLY CLEAR ALONG RIDGE AXIS. FROM THE OTHER DIRECTION CIRRUS OVER OHIO/LAKE ERIE HAS CONTINUED TO SPIN NORTHWEST TOWARD LOWER MICHIGAN...BUT HAS MADE NO PROGRESS DUE TO THE UPPER RIDGE OVERHEAD. GENERAL TREND WILL BE TO PROGRESS THE RIDGE SOUTH AND EAST AS THE SHORTWAVE PUSHES THROUGH...WHICH SHOULD FURTHER LIMIT THE NORTHWARD EXTENT TO THE SOUTHERN CLOUDS. WITH ALL THIS SAID...WILL KEEPS SKIES SUNNY FOR TODAY. MAY SEE SOME WISPS OF CIRRUS...BUT OVERALL THE DAY WILL BE SUNNY. TEMPERATURES YESTERDAY CLIMBED TO NEAR 60F. MAY SEE SOME WARMING AHEAD OF THE WEAKENING COLD FRONT...AND TEMPERATURES ARE STARTING OUT 5-10F WARMER THAN YESTERDAY. WITH FULL SUN WE SHOULD BE ABLE TO EDGE TOWARD/INTO THE LOWER 60S...WHICH AGREES WITH UPSTREAM READINGS FROM YESTERDAY. WEAK GRADIENT FOR LAKE BREEZES...WHICH SHOULD HOLD TEMPERATURES LOWER NEAR THE LAKES AGAIN. REMNANTS OF THE FIRST FRONT CLEAR THROUGH THE CWA BY THIS EVENING...WITH WEAK NORTHERLY FLOW DEVELOPING BEHIND IT. WITH THE WEAK NATURE OF THE BOUNDARY...MAIN COLD ADVECTION HOLDS OFF UNTIL THE SECONDARY FRONT MAKES IT THROUGH...MORE LATE TONIGHT INTO SATURDAY. MAIN QUESTION WITH THIS FEATURE REVOLVES AROUND CLOUDS COVER. 00Z MODELS CONTINUE TO SHOW DECENT LOW-LEVEL MOISTURE INCREASING LATE TONIGHT ACROSS THE NORTHERN CWA. D3D/VIS-5D COLUMN TRAJECTORIES INDICATE THE SOURCE AIRMASS IS ACROSS NORTHERN MANITOBA. CURRENT SATELLITE/METARS SHOW A WIDESPREAD AREA OF MVFR CLOUDS THROUGH THIS AREA...FROM FAR NORTHERN SASKATCHEWAN TO NORTHERN ONTARIO. THIS AREA OF MOISTURE IS WHAT WOULD MAKE IT INTO LOWER MICHIGAN LATE TONIGHT. LIMITING FACTOR IS THAT D3D TRAJECTORIES ALSO SHOW PARCELS FROM NORTHERN MANITOBA SLOWLY SUBSIDING BY THE TIME THEY REACH THE CWA...WHICH MAY WORK TO ERODE THE SOUTHERN EDGE OF THE CLOUDS. HOWEVER ENOUGH MOISTURE IS DEPICTED ACROSS THE REGION...AS WELL AS WITH THE DIURNAL TIMING LATE AT NIGHT...TO KEEP THE MENTION OF BECOMING MOSTLY CLOUDY LATE ACROSS THE NORTHERN CWA. FORECAST SOUNDINGS SHOW PLENTY OF DRY AIR ABOVE THE INVERSION...WITH DEWPOINT DEPRESSIONS NEAR 20C AND INCREASING THROUGH THE DAY...ALSO SEEN UPSTREAM ON 00Z CYQD OBSERVED SOUNDING. ENOUGH LOW LEVEL MOISTURE AND LOW LEVEL LAPSE RATES TO EXPECT DECENT CU DURING THE DAY AS WELL. EXPECT CLOUD DECK TO START MIXING OUT AND BECOMING MORE CELLULAR DURING THE AFTERNOON...ALLOWING SOME BREAKS OF SUN AND AT LEAST PARTLY SUNNY SKIES. DEPENDING ON THE AMOUNT OF MIXING AND HOW MUCH WE TAP INTO THE DRY AIR ABOVE THE INVERSION...MAY BECOME MOSTLY SUNNY LATE...ALTHOUGH WILL HOLD OFF ON THAT MENTION FOR NOW. WITH ADDITIONAL CLOUDS AND WEAK COLD ADVECTION FOLLOWING THE FRONT...EXPECT HIGHS UP TO 10F COLDER THAN TODAY. SURFACE RIDGE BUILDS ACROSS LOWER MICHIGAN SATURDAY NIGHT...SCOURING OUT THE REMAINING LOWER-LEVEL MOISTURE. ETA/GFS HINT AT MID/UPPER LEVEL MOISTURE INCREASING LATE...BUT WILL HOLD OFF ON THAT MENTION FOR NOW...AND STICK WITH MOSTLY CLEAR OR BECOMING MOSTLY CLEAR FOR THE PERIOD. CLEAR SKIES AND WEAK GRADIENT UNDER RIDGE AXIS...COMBINED WITH SHALLOW COLD AIRMASS FOLLOWING THE FRONT...WILL LEAD TO A COLDER NIGHT WITH TEMPERATURES DROPPING INTO THE 20S IN MOST AREAS. RETURN FLOW DEVELOPS ON SUNDAY...WITH SOME MODERATION IN TEMPERATURES AND HIGHS REBOUNDING BACK NEAR NORMAL. ADDITIONAL MID/UPPER LEVEL MOISTURE AS WELL THOUGH...WITH GENERAL PARTLY SUNNY SKIES. .DTX...NONE. $$ BRAVENDER EXPERIMENTAL GRAPHICAL FORECASTS ARE AVAILABLE ONLINE AT HTTP://WWW.CRH.NOAA.GOV/DTX (ALL LOWER CASE) mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 255 AM EDT FRI APR 11 2003 00Z RAOBS/LATEST WV LOOP AND RUC ANLSYS SHOW SPLIT FLOW ACRS NAMERICA. CWA ON SRN FLANK OF NRLY ZONAL NRN BRANCH FLOW ACRS SRN CAN DOWNWND OF UPR RDGING IN THE CNDN ROCKIES...WITH A POTENT EMBEDDED SHRTWV MOVG ESE ACRS ONTARIO. THIS SHRTWV SUPPORTING A WEAK SFC-H85 COLD FNT DANGLING SW FM SFC LO OVR FAR NRN ONTARIO INTO WRN LK SUP AT 03Z. SFC TEMPS DROP OFF LTL BEHIND THE BNDRY...BUT H85 TEMPS DCRS FM 10C AHD OF FNT TO 4C AT INL AND 0C AT YQD. LOCAL 00Z SDNGS DEPICT A VERY DRY AIRMASS (INL PWAT 0.19 INCH)...SO NOTHING MORE THAN PTCHY CI ASSOCIATED WITH THIS FNT. 00Z INL/YQD SDNGS SHOW SUBSIDENCE INVRN BEHIND FNT ARND H8...AND BOTH THESE SDNGS SHOW A WELL MIXED BLYR UP TO H8. YPL SDNG LOOKS VERY SIMILAR. UNSTABLE NATURE OF LLVL LAPSE RATES SUPPORTED MAX TEMPS INTO THE MID 50S WELL N INTO CAN ON THU. MUCH COLDER NOTED ACRS FAR NW ONTARIO...AND CONSIDERABLE BACKWASH SC NOTED BEHIND SECONDARY COLD FNT IN SHARPER CYC FLOW NR SFC LO OVR FAR NW ONTARIO/NRN MANITOBA. SRN EDGE OF THIS CLD COVER APPEARS TO BE MOVG MORE W-E THAN S...IN LINE WITH MOTION OF SHRTWV THRU ZONAL FLOW ACRS SRN CAN. MAIN FCST CONCERNS TDAY/TNGT WL BE TEMPS FOLLOWING PASSAGE OF DRY COLD FNT AND WHETHER SC OVR FAR NRN ONTARIO CAN MAKE ITS WAY S INTO CWA. 00Z MODELS SHOW ONTARIO SHRTWV CONTG DUE E TDAY WITH WEAK FNT PASSING THRU ENTIRE CWA BY 12Z...FOLLOWED BY WEAK SFC RDGING/DRY AIR/WNW FLOW DOMINATING CWA THRU LATE AFTN...WHEN SECONDARY COLD FNT/HIER H85 RH PROGGED TO APRCH NRN KEWEENAW PENINSULA. GIVEN ZONAL FLOW ALF AND MORE E THAN S MOTION OF SHRTWV AND LO CLD IN ONTARIO... THINK MODELS...ESPECIALLY GFS...ARE TOO AGGRESSIVE AT DRIVING COOLER AIR IN FAR NRN ONTARIO/MANITOBA S INTO THE CWA TDAY. THIS SCENARIO SUGS THAT CWA WL ENJOY ANOTHER WARM AND MOSUNNY DAY...WITH WNW FLOW FAVORING LK SUP MODERATION OF TEMPS ACRS MAINLY THE FAR W CWA AND E OF MQT. LK MI ZNS SHUD SEE MUCH HIER TEMPS THAN YDAY WITH 20KT H925 NW WNDS SUPPRESSING ANY LK BREEZE PUSH INLAND THERE. ALL MOS FCST MAX TEMPS APPEAR ON THE LO SIDE GIVEN UNSTABLE LAPSE RATES/ OBSVD HI TEMPS UPSTREAM WELL N IN CAN ON THU AND WHAT APPEARS TO BE OVERLY AGGRESSIVE PUSH OF COOLER AIR SWD TOO QUICKLY. AS UPR LO DEEPENS OFF THE PAC COAST TNGT...UPR RDG IN CNTRL CAN FCST TO AMPLIFY AND BLD HI PRES IN SCNTRL CAN. THINK THIS EVOLUTION OF THE PRES FIELD WL PUSH COOLER AIR S INTO THE UPR GRT LKS. BUT WITH WEAKENING CYC FLOW AND MAJORITY OF LLVL COLD AIR REMAINING N OF LK SUP...XPCT BACKWASH SC TO BE MUCH LESS WDSPRD THAN OBSVD EARLY THIS MRNG. THINK PCLDY SHUD COVER SKY CONDITION...WITH THE BEST CHC OF MORE CLD OVR THE E THAN THE W CLOSER TO GREATER CAD AND WHERE MODELS SHOW HIER H85 RH (BUT OVERDONE). SFC DWPTS 23 TO 27 UPSTREAM IN SOURCE AIRMASS...AND THIS APPEARS WL BE A LWR LIMIT ON MIN TEMPS WITH SHARP ENUF PRES GRADIENT ON SRN FLANK OF SFC HI TO ALLOW ENUF WND/MIXING TO PREVENT TEMPS FM FALLING THRU DWPT. PREFER HIER ETA/AVN MOS GUIDANCE FOR MINS. SFC/UPR RDGING TO REMAIN DOMINANT ON SAT WITH ACYC FLOW AND RELATIVELY DRY AIRMASS. LINGERING MRNG SC OVR THE E SHUD GRDLY DIMINISH WITH LWRG INVRN HGT/RISING H85 TEMPS SHOWN ON ETA FCST SDNGS UNDER SLOWLY BLDG UPR RDG. NNE FLOW ON SRN FLANK OF ONTARIO HI PRES WL CAUSE CONSIDERABLE LK SUP MODERATION OF MAX TEMPS WITH READINGS NR THE SHORE HOLDING IN THE 30S PER ETA FCST 2M TEMPS. BUT EVEN OVER INLAND AREAS...FCST SDNGS/ALL MOS SUG MAX TEMPS WL HAVE A HARD TIME REACHING 50 WITH SHALLOW WEDGE OF LK MODIFIED COOL AIR UNDER INVRN LWRG TO ARND H9. AS HI PRES RDG SHIFTS TO THE E SAT NGT...ETA MOST AGGRESSIVE SHOWING INCRSG WAD/ISENTROPIC LIFT ON 300K SFC (ABOUT H7) BY LATE SAT NGT BTWN THIS RDG AND FALLING PRES IN NRN MN ASSOCIATED WITH SHRTWV DROPPING ESE E OF UPR RDG IN NRN PLAINS WELL IN ADVANCE OF DEEPENING TROF OVR THE FAR W. ETA EVEN SHOWS AREA OF UPR DVGC OVR FA BY 12Z SUN ACCOMPANYING 80KT H3 JET MAX OVR SRN ONTARIO. ETA ONLY MODEL TO GENERATE QPF OVR THE WRN ZNS LATE SAT NGT. GIVEN ANTECEDENT DRY AIRMASS AND SHARP UPR RDG OVR THE CNTRL NAMERICA DOWNWND OF TROFFING OFF THE W COAST...PREFER DRIER GFS/CNDN MODELS WITH RESPONSIBLE SHRTWV PASSING FARTHER N IN HIER AMPLITUDE RDG. XPCT LOWEST MINS CLOSER TO LWR GFS MOS NUMBERS OVR THE INTERIOR SCNTRL...WITH HIER LO TEMPS ACRS THE N AND W CLOSER TO OVRRNG CLD COVER. SEE NO REASON TO CHG GOING FCST CHC SHRA ON SUN WITH ALL MODELS SHOWING CONTD ISENTROPIC LIFT BTWN DEPARTING HI AND FALLING PRES IN NRN PLAINS. .MQT...NONE. KC mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BUFFALO NY 325 AM EDT FRI APR 11 2003 IT WILL BE A CLOSE CALL FOR SOUTHERN PARTS OF THE FORECAST AREA TODAY AS AN AREA OF RAIN IS FORECAST TO GRAZE THE REGION FROM THE SOUTH. A DEEP CUTOFF OVER SOUTH CAROLINA IS IN THE PROCESS OF SLOWLY LIFTING NORTH...AND AS OF 07Z THE NORTHERN EDGE OF THE RAIN HAS SPREAD INTO CENTRAL PENNSYLVANIA. 00Z ETA AND 06Z RUC MODEL RUNS ARE WOEFULLY SLOW WITH THE CURRENT PLACEMENT OF THE PCPN...WITH THE AVN DOING THE BEST JOB WITH THE 06Z VERIFICATION. GIVEN THE BETTER SHORT TERM HANDLING OF THE PCPN...WILL RELY MORE ON THE AVN FOR POSITIONING THE NORTHERN EXTENT OF THE RAIN FOR THE FIRST PERIOD. AS A RESULT...WILL LEAVE LOW CHC POPS IN PLACE FROM THE EVENING SHIFT CONTINUITY FOR MUCH OF THE WRN SOUTHERN TIER. THE FINGER LAKES REGION AND SITES EAST OF LK ONTARIO WILL BE ON THE EDGE OF THIS PCPN SHIELD THIS AFTERNOON AND EVENING...BUT WILL ONLY CARRY 20-25 POPS FOR THOSE AREAS. OTHERWISE...A PARTLY SUNNY DAY COURTESY OF A NEW ENGLAND SFC RIDGE WITH TEMPS CLIMBING TO NEAR 50. THE UPPER LOW WILL CONTINUE TO MAKE ITS WAY OFF THE MID ATLANTIC COAST TONIGHT AND SATURDAY...WHILE CANADIAN HIGH PRESSURE WILL EXTEND ACROSS THE BULK OF THE GREAT LAKES. WHILE FAIR WEATHER WILL ACCOMPANY THIS SCENARIO...H8 TEMPS WILL DROP TO BETWEEN -4 AND -8C SATURDAY AFTERNOON. AVN ALSO DEPICTS A WEAK UPPER LEVEL TROF DROPPING THROUGH THE REGION LATE IN THE DAY. THE COMBINATION SEEMINGLY HAS THE AVN PRODUCING SOME -SHRA OVER THE REGION...BUT POINT SOUNDINGS SHOW THAT A SUBSIDENCE INVERSION SHOULD KEEP ANY INSTABILITY TO A MINIMUM. WILL KEEP PCPN OUT OF FORECAST FOR SAT AND USE 20 POPS. A BROAD BASED RIDGE OVER THE PLAINS WILL THEN START MOVING EAST ACROSS THE MISSISSIPPI VALLEY. THE RIDGE IS FORECAST TO BE CENTERED OVER THE EASTERN THIRD OF THE COUNTRY BY TUESDAY...WITH A GRADUAL DAY TO DAY WARMING AS A RESULT. WATCH FOR TEMPS TO CLIMB INTO THE LOWER 60S FOR MONDAY...AND MID TO UPPER 60S WITH H8 TEMPS OF +12 FOR TUESDAY. WOULD NOT BE SURPRISED TO SEE SOME LOW 70S...ESP AWAY FROM LAKE ERIE. .BUF...NONE. RSH $$ ny AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON NC 155 AM EDT FRI APR 11 2003 PUBLIC: A BROAD AREA OF SFC LOW PRESSURE XTNDG EAST FM THE CAROLINAS ACROSS THE COASTAL WATERS IS ASSOCD WITH AN UPPER LOW CNTRD OVER SOUTH CAROLINA. A SFC LOW NOW WEST OF FLORENCE SC IS WOBBLING ABOUT UNDER THE UPPER LOW. ANOTHER SFC LOW HAS FORMED OFFSHORE CAPE HATTERAS. RADAR SHOWS AN AREA OF LIGHT RAIN MOVING SLOWLY EAST WHILE ROTATING NNW OVER THE WESTERN FRINGES OF THE CWA ATTM. MODELS IN GOOD GENERAL AGREEMENT ON GRADUALLY CONSOLIDATING...DEEPENING AND MOVING THE SYSTEM OFFSHORE THIS MORNING AND AFTERNOON. THINK ETA IS A BIT SLOW IN MOVING OUT THE LOW...AND THUS OVERDONE WITH THE PRECIPITATION FOR TODAY. WILL GO WITH LIKELY POPS ALONG THE COAST DECREASING TO HIGH CHANCE INLAND FOR THIS MORNING. WILL RAMP DOWN POPS THIS AFTN AND GO WITH VARYING DEGREES OF SLT CHC OVERNIGHT. DRY SHORT WAVE MOVING THRU SAT NIGHT/SUN MRNG WILL INCREASE CLOUD COVER TEMPORARILY BEFORE HIGH PRESSURE FINALLY BEGINS TO TAKE HOLD LATER ON SUNDAY. HIGH PRESSURE WILL DOMINATE INTO THE OUTLOOK PD. SEE NO SUBSTANTIAL SYSTEMS MOVING IN THRU THE OUTLOOK. MARINE: WINDS CURRENTLY IN A LULL AS WEAK SFC LOW PRES INLAND FILLS AND NEW LOW PRES FORMS OFF THE SOUTH CAROLINA COAST. AS THIS NEW LOW MOVES QUICKLY UP THE COAST TODAY...RUC AND ETA SHOW RAPID DEEPENING WITH DEVELOPMENT 25-35 KT WINDS OVER A SMALL PORTION OF THE BACKSIDE OF THE LOW. WILL FORECAST HIGHEST WINDS (25 KT) OVER THE SURF CITY-CAPE FEAR ZONE TODAY. AS THIS LOW CLEARS THE WATERS THIS EVENING...NW WINDS WILL ADVECT COOLER DRIER AIR ACROSS THE AREA. AT 35 NM OFFSHORE...FPSN7 SEAS ARE AT 7 FT WHICH SUGGESTS INITIALIZING THE FORECAST WATERS 5-6 FT WITH A SLOWLY DIMINISHING TREND THROUGHOUT THE NEXT TWO DAYS. THIS WILL REQUIRE A SMALL CRAFT ADVISORY TO REMAIN IN EFFECT THIS ISSUANCE. TONIGHT WINDS ARE FIRMLY OFFSHORE KNOCKING SEAS BACK FURTHER. SPEEDS COULD REACH 25 KT FOR A TIME TONIGHT. SAT/SAT NIGHT FEATURES WEAKENING WESTERLY FLOW. A COLD FRONT WILL MOVE ACROSS THE WATERS SUN MORNING WITH A SHIFT TO NORTHERLY WINDS...BUT SPEEDS SHOULD REMAIN RATHER LIGHT. NO CHANGES TO EXTENDED PORTION OF FORECAST. FCSTID = 40 ILM 61 45 72 51 / 70 20 0 0 LBT 59 44 73 48 / 50 10 0 0 FLO 59 44 74 50 / 50 10 0 0 MYR 55 44 71 52 / 60 10 0 0 .ILM... .NC...SMALL CRAFT ADVISORY SURF CITY TO LITTLE RIVER INLET. .SC...SMALL CRAFT ADVISORY LITTLE RIVER INLET TO S SANTEE RIVER. PUBLIC: REK MARINE: TRA nc AREA FORECAST DISCUSSION...CORRECTED NATIONAL WEATHER SERVICE LA CROSSE WI 130 AM CDT FRI APR 11 2003 MAIN FORECAST FOCUS...TEMPERATURES. DATA ANALYSIS SHOWING AN UPPER LEVEL LONG WAVE RIDGE OVER THE NATIONS MID SECTION. THIS WILL DOMINATE THE WEATHER ACROSS THE REGION THROUGH SUNDAY. LOCAL ANALYSIS AT 06Z SHOWING A TROUGH OF LOW PRESSURE EXTENDING FROM KHYR-KFRM. THIS TROUGH CONTINUES TO MOVE SOUTHEAST. DEWPOINTS ALONG IT ARE IN THE LOWER 30S...BUT DRY OUT CONSIDERABLY BEHIND IT. 00Z ETA/GFS/RUC MODEL INITIALIZATION REASONABLE WITH ALL FIELDS WITH THE EXCEPTION OF THE SURFACE DEWPOINT. THE RUC IS THE ONLY MODEL THAT ACTUALLY HAS THE SURFACE DEWPOINT NEAR REALITY. THE RUC BRINGS MUCH DRIER AIR INTO THE FORECAST AREA BEHIND THE TROUGH. THE DIFFERENCE IS ABOUT 10 TO 15 DEGREES. THIS IS SIGNIFICANT FOR FIRE WEATHER PURPOSES...AS RELATIVE HUMIDITIES WILL BE SIGNIFICANTLY LESS. OTHERWISE...ETA/GFS IN GOOD AGREEMENT. THE TROUGH SHOULD PUSH THROUGH EARLY THIS MORNING...HOWEVER THE COOLER TEMPERATURES WILL BE DELAYED. THEREFORE...HAVE ADJUSTED HIGHS UP SIGNIFICANTLY. COOLER HIGH PRESSURE DOES MOVE INTO THE FORECAST AREA FRIDAY NIGHT AND SATURDAY. SATURDAY NIGHT...LOW PRESSURE MOVES INTO THE PLAINS. THIS CAUSES SOUTHERLY WINDS TO DEVELOP LATE SATURDAY NIGHT. ON SUNDAY...THE PRESSURE GRADIENT INCREASES. 850 MB WIND MAX OF 40 TO 50 KNOTS ALIGNS ITSELF ACROSS THE WIND SWEPT AREAS OF MINNESOTA AND IOWA. HOWEVER...THESE WINDS ONLY TRANSPORT WARM AIR NORTHWARD. THE FORECAST SOUNDINGS INDICATE THAT THERE WILL BE SO MUCH SUBSIDENCE THAT MIXING THESE WINDS DOWN THROUGH THE MIXED LAYER SEEMS UNLIKELY AT THIS TIME. AS FOR CLOUDS THROUGH SUNDAY...VERY LITTLE. TIME/HEIGHT CROSS SECTIONS ONLY SHOW A SLIGHT AMOUNT OF MID-HIGH LEVEL MOISTURE. STRONG SUBSIDENCE BELOW 700 MB WILL PRECLUDE ANY DIURNAL TYPE CLOUDS. .LSE...WATCHES/WARNINGS/ADVISORIES...NONE. $$ KRC wi SOUTHEAST ARIZONA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TUCSON AZ 223 AM MST FRI APR 11 2003 .SYNOPSIS...UNSEASONABLY WARM WEATHER WILL CONTINUE INTO THE UPCOMING WEEKEND UNDER WEAK HIGH PRESSURE. A STRONG STORM SYSTEM OVER THE GULF OF ALASKA WILL MOVE DOWN THE WEST COAST THIS WEEKEND BEFORE TURNING EAST ACROSS ARIZONA MONDAY NIGHT. THIS SYSTEM WILL BRING GUSTY WINDS ON MONDAY...FOLLOWED BY MUCH COOLER WEATHER FOR THE REST OF NEXT WEEK. .DISCUSSION...LATEST WATER VAPOR IMAGERY AND RUC ANALYSIS SHOWS THE VORT CENTER OVER EXTREME SE ARIZONA EXITING THE REGION. THIS SYSTEM ONLY BROUGHT SOME CLOUD COVER TO SE ARIZONA YESTERDAY. ANOTHER WEAKER SECONDARY VORT CENTER OVER SOUTHERN CALIFORNIA WILL MOVE EAST TODAY WITH IR IMAGERY SHOWING A BAND OF CIRRUS ASSOCIATED WITH THIS FEATURE. DURING THE DAY MODELS INDICATE THAT WEAK FLAT RIDGING WILL BUILD ACROSS THE REGION TODAY WITH THE HIGHLY AMPILIFIED AXIS OCCURRING WELL TO THE EAST...OVER THE CENTER OF THE NATION. BEGINNING SATURDAY AND CONTINUING THROUGH MONDAY THE UPPER FLOW WILL BE FROM THE SOUTHWEST IN ADVANCE OF THE PACIFIC STORM DROPPING DOWN FROM THE GULF OF ALASKA. LATEST RUN OF THE GFS INDICATE THAT THE PACIFIC STORM MAY NOT PACK AS MUCH PUNCH WITH RESPECT TO PRECIPITATION AS EARLIER THOUGHT. 00 UTC RUN OF THE AVN SHOW THE DEEP LAYER MOISTURE NOT GETTING INTO MY FORECAST AREA UNTIL AFTER 18 UTC MONDAY AND EVEN THEN THE MOISTURE IN THE MODELS IS DEPICTED AS A NARROW BAND WHICH SHOULD QUICKLY BLOW THROUGH THE REGION. BY 12 UTC TUE ONLY SOME RESIDUAL MOISTURE REMAINS ACROSS THE WHITES AND BY 18Z TUE THE MOISTURE IS RAPIDLY SWEPT INTO COLORADO/NRN NEW MEXICO AS THE UPPER LEVEL ENERGY EJECTS TO THE NE. WINDY CONDITIONS FOR MONDAY STILL SEEM TO BE IN ORDER AS AVN IS ADVERTISING 30 KNOT WINDS AT 850MB AND 40+ KNOTS AT 700MB WITH THE PASSAGE OF THE SYSTEM. SHORTWAVE RIDGING BUILDS IN BEHIND THE SYSTEM TUESDAY NIGHT AND WEDNESDAY WITH A LONG WAVE TROUGH RIDING DOWN THE WEST COAST ON THURSDAY AND THURSDAY NIGHT. BY FRIDAY THE SYSTEM SWINGS THROUGH ARIZONA BUT THAT IS BEYOND THE SCOPE OF THE FORECAST PERIOD FOR THIS PACKAGE. ON THURSDAY AS THE SYSTEM APPROACHES THE AREA...GFS INDICATES THAT THE BULK OF THE MOISTURE WILL RESIDE WELL TO THE NORTH OF THE REGION. WILL THAT SAID... FOR PRECIP CHANCES WILL KEEP A CHANCE GOING BEGINNING MONDAY AFTERNOON AND CONTINUING THROUGH MONDAY NIGHT. BY TUESDAY MORNING WILL SHAVE POPS FROM GRIDS/ZONES CONSIDERABLY...MAINLY LEAVING ONLY A 20-30 PERCENT POPS IN THE GRIDS OVER THE WHITE MOUNTAINS BY THAT TIME. WEATHER SHOULD BE COMPLETELY GONE BY MIDDAY TUESDAY AS DYNAMICS QUICKLY MOVE NE. THEREAFTER...NO MENTION OF POP NEEDED FOR THE REMAINDER OF THE FORECAST. MOLLERE .TWC...NONE. $$ az AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CHICAGO IL 940 AM CDT FRI APR 11 2003 DISCUSSION FOR 1000 AM ZONE UPDATE RIDGE OF MODERATING CONTINENTAL HIGH PRESSURE EXTENDS OVER SOUTHERN GREAT LAKES REGION...WITH A WEAK COLD FRONT CURRENTLY ANALYZED FROM NORTH CENTRAL IOWA NORTHEAST INTO CENTRAL WISCONSIN. SUNNY SKIES TO PREVAIL WITH STRONG SUBSIDENCE FROM EAST COAST SYSTEM DRYING OUT ATMOSPHERE. ADJUSTED WINDS AND TEMPS FOR MOST ZONES. THINK THAT COLD FRONT WILL APPROACH ROCKFORD LATE THIS AFTERNOON...LEAVING MOST OF NORTHERN ILLINOIS AND NORTHWEST INDIANA PREFRONTAL. RUC THETA E PROFILE WOULD SUGGEST MIXING TO 850 MB TODAY. 12Z DVN SOUNDING AND LOCAL ACARS SOUNDINGS SHOW MIXING WILL YIELD ABOUT 70 DEGREES. THE ONLY CONCERN OTHER THAN THE COLD FRONT IS NEAR THE LAKE...WHERE A LAKE BREEZE IS ONCE AGAIN FORECASTED LATE THIS AFTERNOON...BRINGING A DRAMATIC TEMPERATURE CONTRAST AS IS THE NORM FOR THIS TIME OF THE YEAR (WATER TEMPS HOVERING AROUND 40 DEGREES). .CHI...NONE. ROGOWSKI AVIATION DISCUSSION FOR 12Z TAFS CLEAR SKIES AND LIGHT/VRBL WINDS EARLY SHOULD GIVE WAY TO NW WIND AS MIXING STARTS. MAIN ITEM IS FRONT COMING DOWN LAKE LATE AFTERNOON WHICH WILL SWINGS WIND TO N OR NE AND INCREASE SPEEDS. JUST SOME SCT CLOUDS WITH FROPA. WIND THEN STAYS NE OR N THRU NIGHT. AF il SOUTHEAST MICHIGAN AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 1107 AM EDT FRI APR 11 2003 A SURFACE TROUGH AXIS EXTENDING FROM SOUTHERN WISCONSIN TO NORTHEAST LOWER MICHIGAN WILL STILL MOVE SOUTH THIS AFTERNOON AND WEAKEN PER LATEST RUC ANALYSIS. SKIES WILL REMAIN SUNNY AS THERE IS A LACK OF MOISTURE ALONG THE BOUNDARY. MIXING TO 880MB (THE HEIGHT WE MIXED TO YESTERDAY) ON THIS MORNINGS DTX SOUNDING WOULD SUPPORT AFTERNOON HIGHS IN THE LOWER 60S. WITH THE MESO ETA INDICATING SOME SLIGHT WARMING AT 925MB THIS AFTERNOON...SOME READINGS ARE LIKELY TO HIT THE MID 60S. I WILL THEREFORE ISSUE AN UPDATE TO INCREASE AFTERNOON HIGHS ACCORDINGLY. STILL EXPECTING LAKE BREEZES TODAY...SO READINGS WILL BE COOLER NEAR THE GREAT LAKES. CONSIDINE .............PREVIOUSLY ISSUED AREA FORECAST DISCUSSION............ 00Z RAOBS/WATER VAPOR LOOP SHOW SOUTHERN STREAM LOW OVER THE SOUTHEAST CONUS...WITH NORTHERN STREAM LOW NEAR JAMES BAY. GREAT LAKES SANDWICHED BETWEEN THESE SYSTEMS UNDER UPPER SHORTWAVE RIDGE...FROM LONGWAVE RIDGE OVER THE PLAINS. SURFACE ANALYSIS SHOWS LOWS OFF THE SOUTHEAST COAST AND NEAR HUDSON BAY...WITH NARROW RIDGE ACROSS SOUTHERN LOWER. COLD FRONT FROM THE NORTHERN LOW EXTENDS ACROSS THE NORTHERN GREAT LAKES AND INTO MINNESOTA...WITH SECONDARY FRONT WEST THROUGH LAKE WINNIPEG. IR SATELLITE SHOWS CLEAR SKIES ACROSS SOUTHEAST MICHIGAN...WITH CIRRUS FROM THE SOUTHERN SYSTEM NOT MAKING MUCH PROGRESS PAST LAKE ERIE...AND LITTLE IN THE WAY OF ANY CLOUDS WITH THE FIRST COLD FRONT. QUIET AND DRY FORECAST...WITH ONLY CONCERNS REVOLVING AROUND TEMPERATURES AND CLOUDS. SHORTWAVE OVER WISCONSIN SHARPER ON WATER VAPOR LOOP THAN DEPICTED BY 00Z MODELS...ALTHOUGH THE 03Z RUC HAS TRENDED A BIT STRONGER. SURFACE FRONT NOT THAT IMPRESSIVE...AND WEAKENS FURTHER/SHEARS OUT AS THE MAIN LOW TRACKS EAST THROUGH NORTHERN QUEBEC. NOT MUCH IN THE WAY OF CLOUDS WITH THIS FEATURE...WITH JUST A THIN AND NARROW RIBBON OF CIRRUS ACROSS UPPER MICHIGAN/WISCONSIN. DOWNSTREAM ACROSS SOUTHEAST MICHIGAN SKIES ARE CURRENTLY CLEAR ALONG RIDGE AXIS. FROM THE OTHER DIRECTION CIRRUS OVER OHIO/LAKE ERIE HAS CONTINUED TO SPIN NORTHWEST TOWARD LOWER MICHIGAN...BUT HAS MADE NO PROGRESS DUE TO THE UPPER RIDGE OVERHEAD. GENERAL TREND WILL BE TO PROGRESS THE RIDGE SOUTH AND EAST AS THE SHORTWAVE PUSHES THROUGH...WHICH SHOULD FURTHER LIMIT THE NORTHWARD EXTENT TO THE SOUTHERN CLOUDS. WITH ALL THIS SAID...WILL KEEPS SKIES SUNNY FOR TODAY. MAY SEE SOME WISPS OF CIRRUS...BUT OVERALL THE DAY WILL BE SUNNY. TEMPERATURES YESTERDAY CLIMBED TO NEAR 60F. MAY SEE SOME WARMING AHEAD OF THE WEAKENING COLD FRONT...AND TEMPERATURES ARE STARTING OUT 5-10F WARMER THAN YESTERDAY. WITH FULL SUN WE SHOULD BE ABLE TO EDGE TOWARD/INTO THE LOWER 60S...WHICH AGREES WITH UPSTREAM READINGS FROM YESTERDAY. WEAK GRADIENT FOR LAKE BREEZES...WHICH SHOULD HOLD TEMPERATURES LOWER NEAR THE LAKES AGAIN. REMNANTS OF THE FIRST FRONT CLEAR THROUGH THE CWA BY THIS EVENING...WITH WEAK NORTHERLY FLOW DEVELOPING BEHIND IT. WITH THE WEAK NATURE OF THE BOUNDARY...MAIN COLD ADVECTION HOLDS OFF UNTIL THE SECONDARY FRONT MAKES IT THROUGH...MORE LATE TONIGHT INTO SATURDAY. MAIN QUESTION WITH THIS FEATURE REVOLVES AROUND CLOUDS COVER. 00Z MODELS CONTINUE TO SHOW DECENT LOW-LEVEL MOISTURE INCREASING LATE TONIGHT ACROSS THE NORTHERN CWA. D3D/VIS-5D COLUMN TRAJECTORIES INDICATE THE SOURCE AIRMASS IS ACROSS NORTHERN MANITOBA. CURRENT SATELLITE/METARS SHOW A WIDESPREAD AREA OF MVFR CLOUDS THROUGH THIS AREA...FROM FAR NORTHERN SASKATCHEWAN TO NORTHERN ONTARIO. THIS AREA OF MOISTURE IS WHAT WOULD MAKE IT INTO LOWER MICHIGAN LATE TONIGHT. LIMITING FACTOR IS THAT D3D TRAJECTORIES ALSO SHOW PARCELS FROM NORTHERN MANITOBA SLOWLY SUBSIDING BY THE TIME THEY REACH THE CWA...WHICH MAY WORK TO ERODE THE SOUTHERN EDGE OF THE CLOUDS. HOWEVER ENOUGH MOISTURE IS DEPICTED ACROSS THE REGION...AS WELL AS WITH THE DIURNAL TIMING LATE AT NIGHT...TO KEEP THE MENTION OF BECOMING MOSTLY CLOUDY LATE ACROSS THE NORTHERN CWA. FORECAST SOUNDINGS SHOW PLENTY OF DRY AIR ABOVE THE INVERSION...WITH DEWPOINT DEPRESSIONS NEAR 20C AND INCREASING THROUGH THE DAY...ALSO SEEN UPSTREAM ON 00Z CYQD OBSERVED SOUNDING. ENOUGH LOW LEVEL MOISTURE AND LOW LEVEL LAPSE RATES TO EXPECT DECENT CU DURING THE DAY AS WELL. EXPECT CLOUD DECK TO START MIXING OUT AND BECOMING MORE CELLULAR DURING THE AFTERNOON...ALLOWING SOME BREAKS OF SUN AND AT LEAST PARTLY SUNNY SKIES. DEPENDING ON THE AMOUNT OF MIXING AND HOW MUCH WE TAP INTO THE DRY AIR ABOVE THE INVERSION...MAY BECOME MOSTLY SUNNY LATE...ALTHOUGH WILL HOLD OFF ON THAT MENTION FOR NOW. WITH ADDITIONAL CLOUDS AND WEAK COLD ADVECTION FOLLOWING THE FRONT...EXPECT HIGHS UP TO 10F COLDER THAN TODAY. SURFACE RIDGE BUILDS ACROSS LOWER MICHIGAN SATURDAY NIGHT...SCOURING OUT THE REMAINING LOWER-LEVEL MOISTURE. ETA/GFS HINT AT MID/UPPER LEVEL MOISTURE INCREASING LATE...BUT WILL HOLD OFF ON THAT MENTION FOR NOW...AND STICK WITH MOSTLY CLEAR OR BECOMING MOSTLY CLEAR FOR THE PERIOD. CLEAR SKIES AND WEAK GRADIENT UNDER RIDGE AXIS...COMBINED WITH SHALLOW COLD AIRMASS FOLLOWING THE FRONT...WILL LEAD TO A COLDER NIGHT WITH TEMPERATURES DROPPING INTO THE 20S IN MOST AREAS. RETURN FLOW DEVELOPS ON SUNDAY...WITH SOME MODERATION IN TEMPERATURES AND HIGHS REBOUNDING BACK NEAR NORMAL. ADDITIONAL MID/UPPER LEVEL MOISTURE AS WELL THOUGH...WITH GENERAL PARTLY SUNNY SKIES. .DTX...NONE. $$ BRAVENDER EXPERIMENTAL GRAPHICAL FORECASTS ARE AVAILABLE ONLINE AT HTTP://WWW.CRH.NOAA.GOV/DTX (ALL LOWER CASE) mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BURLINGTON VT 1007 AM EDT FRI APR 11 2003 ...STILL SOME UNCERTAINTY WITH HOW FAR NORTHERN EDGE OF PRECIP GETS LATE TODAY AND TONIGHT... OVERALL FCST IN GOOD SHAPE AND WL ONLY MAKE SOME MINOR ADJUSTMENTS TO WORDING AND CLOUD COVER. ALSO...BASED ON EXPECTED CLOUD COVER AND SFC FLOW WL ADJUST TEMPS DOWN A FEW DEGREES ACRS THE SOUTHERN CWA AND UP ACRS WESTERN CWA. WATER VAPOR THIS MORNING SHOWS STRONG MID/UPPER LVL LOW PRES ACRS NC SLOWLY MOVING NE TOWARD OUR CWA WITH PLENTY OF ULVL MOISTURE STREAMING INTO THE REGION. MEANWHILE...UPSTREAM S/W ENERGY ACRS GREAT LAKES WL HELP TO DEFLECT SYSTEM TO OUR SOUTH AND EAST THIS AFTERNOON AND TONIGHT. WATER VAPOR TRENDS SUGGEST NORTHWEST DEVELOPMENT OF MOISTURE ACRS WESTERN/NORTHERN NY ASSOCIATED WITH SOUTHERN SYSTEM HAS DECREASED AND WL BEGIN TO PUSH EAST SHORTLY. OVERALL MODELS IN GOOD AGREEMENT WITH UPPER LVL FEATURES AND ASSOCIATED TRACK OF SFC LOW PRES ACRS MID ATLANTIC COASTLINE THROUGH THE SHORT TERM. HOWEVER...SOME DISAGREEMENT AMONG THE NORTHERN EXTENT OF MOISTURE AND LIFT WITH SYSTEM. BASED ON CRNT RADAR TRENDS AND SFC OBS MODELS ARE HAVING SOME DIFFICULTIES WITH POSITION/MOVEMENT OF NORTHERN EDGE OF PRECIP SHIELD. HOWEVER...FEEL THE GFS 850-500MB RH FIELD OF 60-70% LINE UP NICELY WHERE THE CRNT RADAR IS DEPICTING PRECIP. THEREFORE...WL CONTINUE TO MENTION CHC OF -RW ACRS SOUTHERN CWA TODAY AND KEEP REST OF FCST DRY. OTHERWISE...WL MAKE A FEW MINOR ADJUSTMENTS TO CRNT CLOUD COVER BASED ON SATL PICS AND OBS. A LARGE TEMP RANGE CAN BE EXPECTED TODAY ACRS THE CWA BASED ON EXPECTED CLOUD COVER AND PRECIP. RUC 2M TEMPS SUGGEST HIGHS NEAR 60F AT KMSS WITH ONLY U40S ACRS RUTLAND/WINDSOR COUNTIES. GIVEN...MSS IS ALREADY 52F AT 14Z WL ADJUST WESTERN ZONES UP AND MENTION HIGHS ONLY IN THE U40S ACRS OUR SOUTHERN CWA. OTHERWISE...NO OTHER CHANGES EXPECTED TO CRNT FCST. .BTV...NONE. TABER vt AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WAKEFIELD VA 1010 AM EST FRI APR 11 2003 UPDATED GRIDDED AND TEXT FCST PRODUCTS TO TAKE INTO ACCOUNT CURRENT OBSERVATIONAL AND MODEL TRENDS. OTHER THAN SPOTTY -DZ...AKQ FORECAST AREA GENERALLY PCPN FREE ATTM HOWEVER LARGE AREA PCPN MOVG N FM SE NC COAST. RECENT RUC/MESOETA RUNS SUGG MAIN BODY OF THIS PCPN HUGS COASTLINE BUT SOME LIGHTER PCPN SHUD PUSH INTO INLAND AREAS AS WELL AS IT CROSSES INTO SRN VA THIS AFTN. OVERALL...LOWERED POPS 10-20% CWA-WIDE. UPR LOW SPINNING ALG SC CST WL VERY SLOWLY MOVE NE ALG CAROLINA COASTLINE TODAY. WATER VAPOR SHOWS DRY AIR WORKING INTO THE LARGE CIRCULATION WHICH SHUD AID CLOUD EROSION...BUT AREA MORNING SOUNDINGS VERY WET IN THE LOW LVLS SO WL BE HARD FOR SUN TO POKE THRU. LOWERED AFTN HIGHS A FEW DEGS PER EXPECTED OVC. CWF: RAISE SCA FOR CURRITUCK SOUND. HEAVY SURF ADVISORY RMNS IN EFFECT THIS AFTN. PREV DISC BLO: -------------------------------------------------------------------- UPR LO SPINNING NR THE SC CST WILL FINALLY LIFT ENE OFF THE NC CST INTO THIS EVENG...THEN EVENTUALLY OFF THE SRN NEW ENG CST BY 12Z SAT. UNTIL THIS SYS MOVES WELL NE OF THE AREA LATER TNGT/ERLY SAT MORNG...THE THREAT FOR SHRAS WILL CONTINUE ACRS THE FA. WILL GO LIKELY POPS IN THE E AND HI CHC POPS IN THE W. TEMPS WILL CLIMB INTO THE LWR TO MID 50S TODAY AS MARINE AIRMASS SPREADS INTO THE REGION. LOW CONTINUES TO MOVE AWAY TWRD THE CANADIAN MARITIMES ON SAT...AS HI PRES STARTS TO BLD SE FM THE GRT LKS. WELCOMED SUNSHINE AND TEMPS IN THE 60S WILL RESULT. HI PRES WILL THEN BLD OVR FA ON SUN...THEN REMAIN ALONG OR JUST OFF THE MID ATLC CST FOR MON INTO WED. -------------------------------------------------------------------- .AKQ... .MD...SCA CSTL WTRS FM FENWICK ISL TO CHINCOTEAGUE. HEAVY SURF ADVISORY AND CSTL WTRS. .NC...SCA CSTL WTRS FM NC/VA BORDER TO CURRITUCK BEACH LIGHT AND CURRITUCK SOUND. HEAVY SURF ADVISORY S CHES BAY CSTL WTRS. .VA...SCA CHES BAY S OF SMITH PT...AND CSTL WTRS FM CHINCOTEAGUE TO NC/VA BORDER. HEAVY SURF ADVISORY CSTL WTRS. CULLEN va AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CHICAGO IL 1235 PM CDT FRI APR 11 2003 AVIATION DISCUSSION FOR 18Z TAFS VFR NEXT 24 HOURS. ONLY CONCERN IS WINDS. LAKE BREEZE JUST FORMING AND SHOULD BE TO ORD WITHIN NEXT HOUR THEN MDW 1-2 HRS. THEN WEAK COLD FRONT COMES THRU LATER THIS AFTERNOON BRINGING NNE WINDS ACROSS ENTIRE AREA. NNE FLOW CONTINUES REST OF THE PERIOD AND SHOULD PICK UP AGAIN WITH SOME GUSTS MID TO LATE MORNING SAT WITH A LITTLE MIXING AND TIGHTER GRADIENT AS RIDGE MOVES NORTH OF AREA. CMS DISCUSSION FOR 1000 AM ZONE UPDATE RIDGE OF MODERATING CONTINENTAL HIGH PRESSURE EXTENDS OVER SOUTHERN GREAT LAKES REGION...WITH A WEAK COLD FRONT CURRENTLY ANALYZED FROM NORTH CENTRAL IOWA NORTHEAST INTO CENTRAL WISCONSIN. SUNNY SKIES TO PREVAIL WITH STRONG SUBSIDENCE FROM EAST COAST SYSTEM DRYING OUT ATMOSPHERE. ADJUSTED WINDS AND TEMPS FOR MOST ZONES. THINK THAT COLD FRONT WILL APPROACH ROCKFORD LATE THIS AFTERNOON...LEAVING MOST OF NORTHERN ILLINOIS AND NORTHWEST INDIANA PREFRONTAL. RUC THETA E PROFILE WOULD SUGGEST MIXING TO 850 MB TODAY. 12Z DVN SOUNDING AND LOCAL ACARS SOUNDINGS SHOW MIXING WILL YIELD ABOUT 70 DEGREES. THE ONLY CONCERN OTHER THAN THE COLD FRONT IS NEAR THE LAKE...WHERE A LAKE BREEZE IS ONCE AGAIN FORECASTED LATE THIS AFTERNOON...BRINGING A DRAMATIC TEMPERATURE CONTRAST AS IS THE NORM FOR THIS TIME OF THE YEAR (WATER TEMPS HOVERING AROUND 40 DEGREES). .CHI...NONE. ROGOWSKI il AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 415 PM EDT FRI APR 11 2003 FORECAST CONCERNS INCLUDE TEMPS IN THE SHORT TERM...AND TEMPS/POPS THROUGH THE EXTENDED AS WX PATTERN GETS MORE INTERESTING NEXT WEEK. HIGH PRES BUILDING ACROSS LAKE SUPERIOR...WITH ASSOCIATED LOW CLOUD DECK NOW IN NORTHERN PART OF LAKE. WITH ELY PROGRESSION OF SHORTWAVE ALOFT...CLOUD DECK MAKING AS MUCH HEADWAY EAST AS SOUTH. TEMPS HAVE WARMED NICELY ONCE AGAIN...INTO 50S OR LOWER 60S...BUT LOCATIONS NEAR THE SUPERIOR SHORE HAVE COOLED CONSIDERABLY (TO AROUND 40F) AS ONSHORE FLOW INCREASES. WATER VAPOR IMAGERY SHOWS BUILDING RIDGE IN HIGH PLAINS...W/ DIGGING PACIFIC TROF OUT WEST. RUC AND MESOETA SHOW 925MB AND 850MB TEMPS DROPPING TO BELOW ZERO TONIGHT AS COOL AIR OOZES OVER LAKE. W/ INCREASE IN MOISTURE AND DRY AIR ABOVE INVERSION HEIGHT OF ABOUT 3.5FT DEVELOPING...DRIZZLE MAY BECOME A POSSIBILITY. BUT W/ ERODING NATURE OF CLOUDS TO NORTH...AND NO OBSERVED PCPN UNDERNEATH...WILL KEEP W/ JUST CLOUDS TONIGHT INTO FIRST HALF OF SATURDAY. NORTHEAST WIND WILL MEAN MUCH COOLER TEMPS TOMORROW...ESPECIALLY FOR THOSE NEAR LAKE SUPERIOR. EXPECTING LAKESHORE HIGHS ONLY IN MID/UPR 30S...TO UPR 40S SOUTH. BETTER MIXING SHOULD ERODE THE CLOUDS A GREAT DEAL BY AFTN. AFTER COOLER NIGHT SAT NIGHT...HIGH PRES DRIFTS EAST AND ALLOWS FOR WAA TO KICK IN SUNDAY. ETA AND AVN SHOW MODEST ISENTROPIC LIFT ON 300-310K SFCS...BUT W/ DRY AMS IN PLACE THINK THAT SHOULD JUST SEE INCREASE IN MID/HIGH CLDS (CPD'S CONCURS WITH THIS). WILL KEEP W/ LOW CHANCE POPS GOING FOR LATE SUN INTO EARLY MON THOUGH WITH WARM FRONT...THOUGH BEST UPR SUPPORT WILL BE TO OUR NORTH WHERE AVN/ETA AND UKMET ARE GENERATING A GOOD DEAL OF QPF (AT NOSE OF 40-50KT H8 JET MAX). PLACEMENT OF SFC FRONT THEN POSES A MAJOR DILEMMA FOR FCST WX/TEMPS MON-WED. ON MON...NOW LOOKS AS IF FRONT WILL PUSH WELL TO OUR NORTH...MEANING A DRY AND VERY WARM DAY AFTER LINGERING -SHRA EARLY. ETA SHOWS H8 TEMPS WARMING TO NEAR 20C IN WEST BY 00Z TUE...WHICH WITH GOOD SW WIND WOULD MEAN POSSIBLE RECORD HIGHS (RECORD AT NWS OFFICE IS 71F). ETA SOUNDINGS...WITH MIXING TO 900MB...WOULD GIVE HIGHS IN LOWER TO MID 70S WEST AND CENTRAL PARTS. ONLY POSSIBLE SETBACK WOULD BE ANY LINGERING FOG/STRATUS (PWATS UP TO NEAR AN INCH W/ MODEL DEWPTS NEAR 50F)...BUT DON'T BELIEVE THIS WILL BE AN ISSUE WITH OFFSHORE WINDS. SO HAVE UPPED TEMPS ACCORDINGLY. EXCEPTION WILL BE ALONG LAKE MICHIGAN (OF COURSE) WHERE FOLKS WILL FEEL WRATH OF ICY LAKE. ALSO...WITH BUILDING RIDGE ALF (H7 TEMPS TO 4C) AND CAPPED AMS (WE WILL BE IN WARM SECTOR)...SHOULD BE A PERIOD OF DRY WX UNTIL PACIFIC TROF NEARS (NOT TIL LATER TUE). SO HAVE ADJUSTED GRIDS TO SHOW DRY WX FROM MON TIL DAYTIME TUE. AGAIN...NEED TO WATCH PLACEMENT OF FRONT. FOR TUE HAVE KEPT W/ CHC TSRA...THOUGH BEST DYNAMICS DON'T ARRIVE TIL LATE IN DAY. BIG FACTOR WILL BE POLAR LOW IN CANADA...WHICH LOOK TO COMPRESS HEIGHTS OVER OUR AREA IN CONFLUENT FLOW IN ADVANCE OF PACIFIC TROF. 00Z GFS CONTINUES TO TRACK SFC LOW TO NORTH OF CWA WED...BUT HAVE SIDED W/ MORE REASONABLE UKMET AND ENSEMBLE MEAN (AND HPC FCST) WHICH TAKE SFC LOW THROUGH WI/NRN LAKE MICHIGAN. IN ALL... MONDAY LOOKS TO BE WARMEST DAY...WITH COOLER TUE (PENDING LOCATION OF FRONT)...AND MUCH COOLER AND WET WED W/ NE WIND. HAVE UPPED POPS TO LIKELY WED AS WELL. BEST CHANCE OF CONVECTION WILL BE TUE INTO WED. AM NOT EXPECTING SEVERE ATTM...THOUGH IF FURTHER-NORTH GFS PANS OUT THIS WILL BE A POSSIBILITY (50KT H8 JET AND PLENTY OF MOISTURE). HAVE INCLUDED MENTION OF SNOW ON THU AS COLD AIR BEHIND THIS SYSTEM IS SUBSTANTIAL (H8 TEMPS BACK DOWN TO WELL BELOW ZERO). HIGH BUILDS IN FRI FOR DRY BUT SEASONABLY COOL DAY...PER ENSEMBLE MEAN. WHEW... THAT'S ALL. .MQT...NONE. JKL mi SOUTH CENTRAL TEXAS FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX 240 PM CDT FRI APR 11 2003 ADDITIONAL...WILL INCLUDE LOW POPS FOR VAL VERDE COUNTY FOR THUNDER THIS EVENING. ACTIVITY PICKED UP BY RUC40 MODEL. LOW LEVEL MOISTURE IS RETURNING AND EXPECT AREAS OF FOG TO DEVELOP OVERNIGHT. FOG AND DRIZZLE SATURDAY NIGHT/SUNDAY MORNING AND AGAIN SUNDAY NIGHT/MONDAY MORNING WITH LOW CLOUDS GIVING WAY TO PARTLY CLOUDY SKIES EACH AFTERNOON. THIS SCENARIO TAKING PLACE BENEATH AN UPPER LEVEL RIDGE WHICH IS REPLACED BY THE NEXT UPPER LEVEL TROUGH TUESDAY. MOST OF THE ENERGY WITH THIS SYSTEM SHOULD OCCUR NORTH OF THE CWA BUT SCATTERED SHOWERS AND THUNDERSTORMS STILL EXPECTED TO DEVELOP. A VERY WEAK COLD FRONT FOLLOWS WEDNESDAY WHICH HANGS UP/WASHES OUT ACROSS THE CWA WITH LITTLE EFFECT. WEAK UPPER AIR DISTURBANCES WILL TRIGGER LOW POPS THURSDAY AND FRIDAY. NIGHT TIME TEMPS WARMING OVER THE WEEKEND WITH HIGHS AND LOWS A BIT ABOVE SEASONAL NORMALS MOST OF NEXT WEEK. PRELIM NUMBERS... AUS 48 80 55 81 0000 DRT 57 86 63 85 0000 SAT 55 81 60 81 0000 .EWX...NONE. 3/19/23 tx