AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE PUEBLO CO 230 PM MST SAT APR 2 2005 .SHORT TERM... (TONIGHT AND SUNDAY) MAIN SHORT TERM CONCERNS ARE TEMPERATURES. CURRENT WATER VAPOR IMAGERY AND RUC UPPER AIR ANALYSIS INDICATING WEAK TO MODERATE WESTERLY FLOW ALOFT ACROSS THE REGION...WITH EASTERN PACIFIC UPPER TROUGH MOVING ONSHORE ACROSS THE PAC NW COAST ATTM. WATER VAPOR IMAGERY ALSO INDICATING MINOR SHORT WAVES EMBEDDED IN THE WESTERLY FLOW ALOFT...WITH ONE MOVING ACROSS NORTHERN NEVADA AND THE OTHER MOVING ACROSS SOUTHERN CALIFORNIA ATTM. VISIBLE SATELLITE AND SFC OBS STILL INDICATING A HEALTHY SNOW FIELD ACROSS SOUTHERN FOOTHILLS AND RATON MESA REGION...WITH KPUB IN THE LOWER 70S AND KTAD IN THE LOWER 50S ATTM. TONIGHT...MINOR EMBEDDED WAVES IN THE WESTERLY FLOW MOVE ACROSS THE REGION AS EASTERN PAC SYSTEM CONTINUES TO MOVE INTO THE PAC NW. WEAK WAVES TO SPREAD MAINLY HIGH LEVEL CLOUDS ACROSS THE STATE OVERNIGHT...WITH LEE TROUGHING ACROSS THE I-25 CORRIDOR KEEPING A WEAK WEST TO SOUTHWEST WINDS AND TEMPERATURES UP OVERNIGHT. HAVE WARMED CURRENT GRIDS UP A NOTCH...ESPECIALLY LOWER SLOPES OF THE EASTERN MTS WITH GAP FLOWS SETTING UP. LATEST RUNS OF NAM PRINTING SOME QPF ACROSS THE SW AND CENTRAL MTS...AND HAVE ADDED SOME SLIGHT POPS WITH MAINLY FLURRIES POSSIBLE ACROSS THE HIGHEST ELEVATIONS ONLY...AS LOW LEVEL MOISTURE PRETTY SPARSE. SUNDAY...WEST TO SOUTHWEST FLOW INCREASES ACROSS THE REGION AS PAC NW SYSTEM BEGINS TO DIG ACROSS THE GREAT BASIN. LEE TROUGHING MOVES ACROSS THE EASTERN PLAINS...AND WITH LAPSE RATES AROUND 8C/KM SUPPORTING GOOD MIXING...WILL SEE SOUTH TO SOUTHWEST WINDS OF 15 TO 20 MPH DEVELOP ACROSS THE EASTERN PLAINS IN THE AFTERNOON. H7 TEMPS WARM SLIGHTLY...AND WITH DOWNSLOPE WINDS...COULD SEE TEMPS IN THE 70S TO LOWER 80S ACROSS THE EASTERN PLAINS...THOUGH HAVE TEMPERED HIGHS A TAD WITH SOME HIGH LEVEL CLOUDS MOVING ACROSS THE REGION. HAVE ALSO GONE BELOW GUIDANCE VALUES ACROSS THE SOUTHERN FOOTHILLS...WITH SNOW COVER CONTINUING TO MELT. -MW .LONG TERM... (SUNDAY NIGHT THROUGH SATURDAY) MAIN FORECAST CONCERN IS MONDAY NIGHT/TUESDAY STORM. MODELS STILL STRUGGLING TO CAPTURE INCOMING UPPER TROUGH...WITH A WIDE VARIETY OF SOLUTIONS AVAILABLE. GFS HAS BEEN FAIRLY CONSISTENT...PORTRAYING A MORE NORTHERN SOLUTION...WITH THE UPPER LOW NOT CLOSING OFF UNTIL IT EJECTS INTO WRN KS ON TUES. ETA HAS BEEN A LITTLE MORE ERRATIC... WITH 12Z RUN VERY DEEP AND FARTHER WEST WITH THE CLOSED LOW...WHILE 18Z RUN IS SLIGHTLY WEAKER AND FARTHER NORTH. FOR THIS FORECAST CYCLE...GRIDS WILL LEAN TOWARD THE STRONGER 12Z ETA SOLUTION...AS ALL MODELS...EVEN THE ECMWF AND UKMET...HAVE BEEN TOO WEAK WITH UPPER TROUGHS AMPLIFYING OVER THE SRN ROCKIES THE LAST FEW WEEKS. WILL NOTE THAT AIR MASS WITH THIS STORM LOOKS SLIGHTLY WARMER THAN THE PREVIOUS SYSTEM...WHICH SHOULD KEEP THE RAIN/SNOW LINE ABOVE 5500 FEET OR SO THIS TIME AROUND. DIDN'T MAKE MANY BIG GRID CHANGES...BUT BUMPED UP POPS ON THE PALMER DIVIDE/TELLER COUNTY MON NIGHT...AS PRECIP TENDS TO START THEIR EARLIER THAN MODEL FCSTS. ALSO DELAYED THE PRECIP/TSRA CHANCE UNTIL LATER MON AFTERNOON OVER THE PLAINS. REALLY CRANKED THE WINDS UP TUES...AS ETA HAS SOME 70 KNOT FLAGS AT 700 MB DURING THE DAY. RIDGE THEN REBUILDS FOR WARMER AND DRIER WEATHER THROUGH FRIDAY... BEFORE NEXT UPPER TROUGH MOVES INTO THE SRN ROCKIES SATURDAY. INITIAL THOUGHT IS THIS SYSTEM LOOKS WARMER AND SLOWER THAN PREVIOUS FEW...SO ONLY ADDED POPS TO FAR WRN ZONES AT THIS POINT...AND KEPT TEMPS WARMER THAN MEX GUIDANCE SAT AFTERNOON. --PETERSEN && .PUB WATCHES/WARNINGS/ADVISORIES...NONE. && $$ co AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TALLAHASSEE FL 845 PM EST SAT APR 2 2005 .SHORT TERM... WILL UPDATE THE ZONES TO REMOVE THE WIND ADVISORY. MADE A FEW TWEAKS TO WINDS IN THE GRIDS...BUT OVERALL NO SIGNIFICANT CHANGES WERE MADE. && .MARINE... LATEST RUC GUIDANCE SHOWS WINDS DROPPING OVERNIGHT. BELIEVE WE CAN DOWNGRADE THE NEAR SHORE WATERS TO SCEC SINCE SEAS ARE LOWER WITH THE LIMITED FETCH. WILL KEEP THE SCA IN EFFECT FOR THE OUTER WATERS WHERE SEAS WILL BE MORE SLOW TO SUBSIDE. && .FIRE WEATHER... RED FLAG WARNING FOR TODAY HAS EXPIRED. WARNINGS AND WATCHES FOR TOMORROW AND MONDAY...RESPECTIVELY REMAIN IN EFFECT. && .TAE WATCHES/WARNINGS/ADVISORIES... AL...NONE. GA...NONE. FL...SMALL CRAFT ADVISORY SUWANNEE RIVER-DESTIN 20-60 NM OFFSHORE. RED FLAG WARNING ALL ZONES SUNDAY 11 AM TILL SUNSET. FIRE WEATHER WATCH ALL ZONES MONDAY NOON TILL SUNSET. && $$ TJT fl AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LINCOLN IL 1041 AM CST SAT APR 2 2005 .DISCUSSION... SURFACE LOW PRESSURE MOVED OUT OF THE MIDWEST QUICKLY THIS MORNING...TAKING SIGNIFICANT CLOUD COVER WITH IT. MIDNIGHT SHIFT CLEARED CLOUDS OUT OF FORECAST AS A RESULT. LITTLE LEFT TO UPDATE. HOWEVER...WITH FULL SUNSHINE...MAX TEMPS IN THE GRIDS ARE A LITTLE LOW. EVEN WITH CAA AT ALL LEVELS OF THE ATMOSPHERE...TEMPERATURES ARE ON A FAST CLIMB WITH ALL THE SUNSHINE. EVEN A LITTLE BIT OF CUMULUS DEVELOPMENT ACROSS THE AREA...WELL BEFORE NOON. AS A RESULT...HAVE TWEAKED MAX TEMPS A BIT AS WELL AS THE CLOUDS. OTHERWISE...FORECAST SEEMS TO BE ON TRACK. && .PREV DISCUSSION... THE NORTHERN AND SOUTHERN STREAM UPPER LEVEL SYSTEMS THAT AFFECTED THE AREA ON FRIDAY ARE CURRENTLY MERGING INTO A SINGLE UPPER LEVEL LOW CENTERED OVER SOUTHERN ILLINOIS AT THE MOMENT. SOUTHERN STREAM ENERGY IS MOSTLY SHEARING OUT OVER TN/KY WHILE AN ELONGATED VORTMAX... JUST ABOUT OVER THE QUAD CITIES AREA ACCORDING TO WV SATELLITE IMAGERY...PUSHES SOUTHWARD. THIS HAS HELPED HANG SOME CLOUDS AND A FEW SHOWERS BACK IN THE AREA...MAINLY ACROSS THE EASTERN COUNTIES. PRIMARY FORECAST CONCERN WILL BE THE TIMING OF THE PRECIP AND REMAINING CLOUD COVER PULLING OUT OF HERE EARLY TODAY...AS WELL AS DETERMINING WIND GUST POTENTIAL FOR THE FIRST PART OF TODAY... OTHERWISE THE WEEKEND LOOKS NICE AND QUIET. SHORT TERM...TODAY THROUGH MONDAY... VORT LOBE ASSOCIATED WITH NORTHERN STREAM ENERGY WHICH IS STREAMING SOUTH INTO THE UPPER LEVEL LOW OVER SOUTHERN IL HAS ALLOWED SOME PESKY CLOUDS AND SHOWERS TO HANG BACK OVER THE AREA...MAINLY AFFECTING THE EASTERN COUNTIES. SFC REFLECTION OF THIS SYSTEM IS WELL EAST OF THE AREA WITH A DEEPENING 994 MB LOW OVER WEST VIRGINIA. RUC AND ETA APPEAR TO HAVE ANALYZED THE AFOREMENTIONED VORT LOBE PROPERLY...AND INDICATE IT SHOULD PASS THROUGH THE CWA ALLOWING SOME CLEARING SKIES BY AFTERNOON... WITH THIS IN MIND... AS WELL AS CURRENT TRENDS... I'VE ADDED A SLIGHT CHANCE RAIN SHOWERS (20 POPS) SOUTH AND EAST OF THE ILLINOIS RIVER. WITH CLOUDS CLEARING OUT BY AFTERNOON...TEMPERATURES SHOULD RECOVER TO THE MID-50S...SO NO BIG CHANGES TO THE GRIDS NECESSARY HERE. WITH THE DEEPENING SFC LOW OFF TO OUR EAST WE'RE IN A BREEZY NORTHWEST FLOW ASSOCIATED WITH THE TIGHT PRESSURE GRADIENT. WINCHESTER PROFILER STILL SHOWING SOME 35 KNOT WINDS JUST OFF THE DECK...AND ETA BUFKIT MOMENTUM XFER TOOL INDICATES GUSTS TO AROUND 25-30 KNOTS POSSIBLE IN MOST AREAS UNTIL THIS AFTERNOON...GUSTING A BIT STRONGER AND LONGER FARTHER SOUTH AND EAST. WILL INCLUDE GUSTY WORDING IN THE GRIDS AND THE ZONES FOR THIS MORNING...AND UNTIL EVENING FOR THE SOUTHEAST COUNTIES. WINDS SHOULD QUICKLY SLACKEN OFF TONIGHT AS SFC RIDGE AXIS NOSES IN. WITH CLEARING SKIES AND SLACKENING WINDS WE SHOULD DECOUPLE... ALLOWING OVERNIGHT LOWS TO DIP DOWN TO THE LOWER 30S ACROSS THE AREA... STAYING ON THE LOWER SIDE OF GUIDANCE. AS THIS SYSTEM CONTINUES TO PUSH EAST OF THE AREA TODAY... RIDGE AXIS WILL BEGIN TO NOSE INTO THE AREA BRINGING PLEASANT SPRING WX TO CENTRAL ILLINOIS FOR MUCH OF THE WEEKEND... IT SHOULD BE A SLOW DAY FOR THE WEATHER COMPLAINTS DEPARTMENT ON MONDAY AS HIGHS SHOULD REACH THE LOW 70S. LONG TERM...TUESDAY THROUGH FRIDAY... MODELS ARE ACTUALLY IN FAIR AGREEMENT THROUGH WEDNESDAY NIGHT...ALL SHOWING A DIGGING SOUTHERN STREAM SHORTWAVE OVER NORTHEASTERN NEW MEXICO BY 12Z TUE WITH A SHORTWAVE RIDING THE NORTHERN STREAM MOVING THROUGH SK AND MT. GFS INDICATING SFC LEE CYCLOGENESIS OVER THE TX PANHANDLE DURING THE DAY ON TUESDAY... WITH A WEAKER SFC LOW OVER MN IN ASSOCIATION WITH THE NORTHERN SYSTEM. THIS IS WHERE SOME DIFFERENCES IN NUMERICAL GUIDANCE BEGIN TO COME INTO PLAY. THE GFS SEEMS TO FAVOR A DOMINANT NORTHERN SYSTEM WHICH DROPS RAPIDLY SOUTH AS THE TWO SYSTEMS BEGIN TO PHASE OVER PA ON FRIDAY... THE CANADIAN IS MUCH SLOWER AND WEAKER WITH THE NORTHERN SYSTEM...WHICH IS QUICKLY ABSORBED INTO A STRONGER SOUTHERN SYSTEM OVER MO BY WEDNESDAY EVENING. THE ECMWF SEEMS TO LIE RIGHT IN BETWEEN...WITH NEITHER SYSTEM DOMINATING...AND SLOWLY PHASING THE TWO INTO AN ELONGATED SHORTWAVE TROUGH ON THURSDAY...WHICH MOVES JUST EAST OF THE AREA ON FRIDAY. FOR THE MOST PART...THE DIFFERENCES HAVE LITTLE AFFECT ON THE FORECAST THROUGH THURSDAY...HOWEVER THE GFS SOLUTION WOULD FAVOR PRECIPITATION LASTING LATER INTO THE WEEK WITH THE DOMINATE NORTHERN SYSTEM PLOWING SOUTH AS IT PHASES INTO ONE CUTOFF LOW OVER PA ON FRI/SAT. ONLY CHANGE TO THE TUE/WED TIME FRAME WAS TO PULL BACK POPS UNTIL LATER TUESDAY IN AGREEMENT WITH SURROUNDING OFFICES. ALSO KEPT THE MENTION OF THUNDER FOR TUE/WED. WITH THE BULK OF THE MODELS AGREEING ON A RATHER POTENT CUTOFF SOMEWHERE NEAR OR EAST OF HERE TOWARDS THE LATTER PART OF NEXT WEEK...I'VE PUT A BIT OF A COOLING TREND ON THE GOING FORECAST FOR THU/FRI... WITH NORTHWEST WINDS BUT JUST A SLIGHT CHANCE OF PRECIP IN FOR NOW. && .ILX WATCHES/WARNINGS/ADVISORIES... .IL...NONE. && $$ HJS/HARDIMAN il AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC 1110 AM EST SAT APR 2 2005 .SHORT TERM (REST OF TODAY)... STRONG STORM SYSTEM WILL BRING A VAREITY OF CONDITIONS TO THE CWA OVER THE NEXT 24 HOURS. FLOOD AND SEVERE THREATS ARE THE MAIN FOCUS FOR THE REMAINDER OF TODAY AND WILL BE FOCUSED ON DURING THIS UPDATE. SYNOPTIC WIND THREAT FOR OUR ENTIRE CWA AND SNOW THREAT ACROSS OUR WESTERN CWA TONIGHT/SUN WILL BE DISCUSSED FURTHER IN THE AFTERNOON PACKAGE. MSL PRESSURE ANALYSIS SHOWS LOW PRESSURE CENTER (ABOUT 992 MB) ACROSS NORTHERN VA AT 15Z. WARM FRONT HAS NUDGED NORTH OF LOWER SOUTHERN MD...AND IS MAKING A RUN TOWARD THE DISTRICT. ALONG AND SOUTH OF THE WARM FRONT...TEMPERATURES HAVE RISEN AOA 60F...WITH DEWPOINTS OF 55-60F ACROSS THIS REGION. AXIS OF MOISTURE/THETA-E CONVERGENCE/ADVECTION EXISTS ROUGHLY FROM BWI SW THROUGH DCA DOWN TO SPOTSY COUNTY...AND POINTS EAST. THIS IS SUPPORTING ORGANIZED CONVECTION...PER LATEST RADAR IMAGES AND WARNINGS THAT HAVE BEEN ISSUED. THIS AREA OF ORGANIZED CONVECTION WILL MOVE EAST THROUGH OUR CWA THROUGH EARLY AFTERNOON. HOWEVER...ANOTHER ROUND OF POTENTIALLY SEVERE CONVECTION IS EXPECTED TO OCCUR AS DRY SLOT BRIEFLY WORKS INTO OUR CWA AND STRONG UPPER LEVEL ENERGY SWINGS ACROSS LATER THIS AFTERNOON/EVENING. SEVERE THREATS ARE SEVERAL- FOLD...AND WILL INCLUDE DAMAGING WINDS...HAIL...AND HEAVY RAINFALL. SHEAR AND HELICITY PROFILES SUGGEST THE POSSIBILITY OF AN ISOLATED TORNADO. THREATS HAVE BEEN HIGHLIGHTED IN HWO PRODUCTS. ZONES WILL HAVE CATEGORICAL POPS FOR OUR ENTIRE CWA AND WILL ENHANCE WORDING FOR OUR CWA...ESPECIALLY EAST OF THE BLUE RIDGE WHICH IS BETTER SUITED FOR SEVERE. && .AVIATION...IFR/MVFR CONDITIONS IN RA/TSRA THROUGH THE EVENING HOURS...THEN IMPROVING CONDITONS TO MVFR/VFR FROM ABOUT 02Z-03Z ON. INCLUDED WIND SHEAR THROUGH AFTERNOON...THEN WIND CONCNERN WILL BE INCREASE SYNOPTIC WINDS FROM THE NW. && .PREVIOUS DISCUSSION... (ISSUED 334 AM EST SAT APR 2 2005) SHORT TERM (TODAY THROUGH TONIGHT)... LOW PRES OVER WV THIS MORNING WILL INTENSIFY RAPIDLY AS IT MOVES SLOWLY NORTHEAST INTO UPSTATE NY BY SUN AFTERNOON. LATEST RADAR IMAGERY SHOWS LARGE AREA OF RAIN ALG FRONTAL ZONE FROM NRN WV SOUTH TO SW VA WHILE LIGHT TO OCCASIONALLY MDT SHOWERS CONTINUE TO LIFT NWD FROM SRN VA INTO NRN VA AND MD AS WARM AIR IS BEING LIFTED ATOP COOL AIR. LATEST SHORT-TERM GUIDANCE SUGGESTS FORCED BAND OF RAIN WILL ENTER THE SW CORNER AROUND 12Z AND TRAVERSE THE REST OF THE CWA BETWEEN 15Z-21Z. 06Z RUC GUIDANCE INDICATES VERY STRONG BANDING FEATURE SO EXPECT VERY INTENSE RAINFALL RATES WITH THIS LINE GIVEN DIVERGENT/DIFLUENT UPPER FLOW...HIGH PWS OF UP TO 1.5 INS AND HIGH K INDICES. AN INCH OR BETTER RAINFALL RATES ARE POSSIBLE IN THE HEAVIEST SHOWERS/TSTMS. THIS WILL BE PLENTY TO CAUSE SMALL STREAM FLOODING GIVEN HIGH STREAM FLOW. A THREAT OF SVR WX MAINLY IN THE FORM DAMAGING WINDS ALSO EXISTS ESPECIALLY AS YOU GO SOUTH AND EAST. LOWER SRN MD AND AREAS CLOSER TO THE CHESAPEAKE BAY HAVE THE GREATEST RISK OF SEEING ANY SVR AS WARM FRONT WILL LIKELY LIFT NORTH OF THOSE AREAS. HVY RAINS PUSHES EAST OF THE BAY AROUND 21Z WITH SHOWERS STILL POSSIBLE IN WRAP AROUND MOISTURE. TONIGHT...STRONG CAA ON BACKSIDE OF DEEPENING MID-LVL CYCLONE AND STRON UPSLOPE WILL CHANGE RAIN TO SNOW SHOWERS ACROSS THE HIGHER ELEVS. SHSN WILL BECOME HEAVY AFTER MIDNIGHT SUN WITH SVRL INCHES OF ACCUMULATION. WINTER STORM WATCH ISSUED FOR FIVE WRN MOST COUNTIES. REST OF THE AREA WILL SEE CLOUDY SHOWERY CONDITIONS AS MOISTURE WRAPS UP AROUND MID CYCLONE. LONG TERM (SUNDAY THROUGH FRIDAY)... VERY CHALLENGING FCST FOR BOTH FCSTRS TNGT. I HV UPPED THE ANTE A BIT IN THE WRN PART OF THE CWA FOR SUN. VERTICALLY STACKED LOW WL BE OVR ERN PA BY SUN MRNG. TIGHT PRES GRAD WL CAUSE A STRNG NWRLY FLOW DURG THE DAY. ETA X-SXNS ARE SHOWING 40-50KT OFF THE SFC IN THE WRN COUNTIES. THINK THERE IS A PTNL THIS WL MIX DOWN. IN GRIDDS WL INDICATE G35 THERE. WHEN NEW MDLS COME IN THERE WL STILL BE TIME TO GO UP TO A HIGH WIND WTCH (GT 40 KT IN AN HR) FOR SUN IF NEEDED ANOTHER CONCERN IS SN IN THE W. STNG NW FLOW...OPEN ERN GRT LKS...CAA COULD LEAD TO SNSH THRUT THE DAY IN THOSE SAME WRN COUNTIES. SHORT TERM FCSTR BLVS THAT SVRL INCHES ARE PSBL TNGT IN THAT WRN AREA...HENCE IT BEHOOVES US TO ISSUE A WINT STRM WTCH...AND IT'S NOT EVEN APRIL FOOLS DAY. FLDG WL CONTINUE TO BE A BIG CONCERN. WE HV ALREADY ISSUED A RVR FLD WRNG FOR THE PTMC...MONOCACY...AND RAPPAHANNOCK FOR RISING WATERS ON SUN AND MON. I'LL BE HONEST...BYND THE SUNDAY PD HAS ONLY RCVD A CURSORY GLANCE FM ME. THE NEW MRF APPEARS STRANGELY FAMILIAR TO WHAT I WAS LOOK AT EXCATLY ONE WK AGO - RDG MVS INTO THE ERN U.S. THRU WED..AND THEN ANOTHER TROF MVS IN TO BRING ANOTHER PD OF WETNESS FOR THE END OF THE WK...SO WE MIGHT BE GOING THRU THIS AGN NEXT WKND. MARINE...SCA ALL WATERS. STRONG LINE OF SHRAS POSSIBLY TSRA WILL SWEEP THROUGH THE WATERS BETWEEN 16-20Z WITH THE POTENTIAL FOR STRONG WIND GUSTS GIVEN HIGH MOMENTUM AIR JUST OFF THE SFC. HYDROLOGY...FLOODING STILL LOOKS LIKELY AS HVY RAINBAND SWEEPS THRU THE AREA LATER TODAY. INCH PER HR RAINFALL RATES POSSIBLY WITH THIS LINE WILL BE MORE THAN ENOUGH TO CAUSE SMALL STREAM FLOODING GIVEN LOW FFG. MINOR RIVER FLOODING STILL EXPECTED AT SVRL POINTS ALG THE POTOMAC/RAPPAHANNOCK RIVER BASINS. THREAT OF FLOODING LESSENS SOMEWHAT AS YOU GO SOUTHWEST ESPECIALLY INVOF CHO. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...FLOOD WATCH FOR DCZ001 FROM 11 PM FRIDAY TO 8 PM SATURDAY. MD...FLOOD WATCH FOR MDZ002>007-009>011-013-014-016>018 FROM 11 PM FRIDAY TO 8 PM SATURDAY. ...WINTER STORM WATCH FOR MDZ002 FROM 8 PM SATURDAY TO 7 PM SUNDAY. VA...FLOOD WATCH FOR VAZ021-025>031-036>042-050>057 FROM 11 PM FRIDAY TO 8 PM SATURDAY. ...WINTER STORM WATCH FOR VAZ021-025-026 FROM 8 PM SATURDAY TO 7 PM SUNDAY. WV...FLOOD WATCH FOR WVZ048>055 FROM 11 PM FRIDAY TO 8 PM SATURDAY. ...WINTER STORM WATCH FOR WVZ048-049-054-055 FROM 8 PM SATURDAY TO 7 PM SUNDAY. MARINE...SMALL CRAFT ADVISORY. && $$ SHORT TERM/AVIATION...PELOQUIN PREV DISCUSSION...ROSA/WOODY md AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE TAUNTON MA 935 PM EST SAT APR 2 2005 .SHORT TERM (REST OF TONIGHT THROUGH SUNDAY)... JUST ANOTHER QUICK UPDATE TO MENTION WE HAVE EXPANDED THE WIND ADVISORY TO INCLUDE ALL ZONES ALONG AND S OF MASS PIKE. GETTING SEVERAL REPORTS OF 40-50 MPH GUSTS IN RI DESPITE STRONG LOW LEVEL INVERSION...AND IN FACT WE HAD A PEAK GUST OF 49KT AT CONIMICUT LIGHT ON NARRAGANSETT BAY! 00Z CHATHAM SOUNDING HAD 50KT WINDS JUST OFF DECK...AND A PILOT REPORT EARLIER FROM AN AIRCRAFT DESCENDING INTO LOGAN REPORTED A 60KT TAILWIND DOWN TO 500 FT! FROM THE 830 PM UPDATE... WE ARE STARTING TO SEE AXIS OF HEAVIEST RAIN SHIFT INTO SOUTHERN NEW ENGLAND. IT EXTENDS IN AN ARC FROM THE MOHAWK AND HUDSON VALLEYS IN NEW YORK STATE INTO WESTERN CT...AND RADAR TRENDS SUGGEST THIS AXIS WILL REMAIN IN A NW/SE ORIENTATION FOR THE NEXT FEW HOURS BEFORE ALIGNING MORE W/E. THIS SHOULD BRING HEAVY RAINFALL TO MUCH OF THE LOWER CT VALLEY THROUGH MIDNIGHT...INCLUDING HARTFORD AND WESTFIELD. ADDITIONAL ELEMENTS LIFTING N TOWARD LONG ISLAND SHOULD BECOME ENTRAINED ALONG THIS AXIS AS WELL. FARTHER E...IT IS STILL A TOUGH CALL AS TO HOW FAST THE HEAVIER RAIN ARRIVES...BUT WE DO EXPECT THAT TO OCCUR AROUND MIDNIGHT. && .LONG TERM (SUNDAY NIGHT THROUGH SATURDAY)... A VERTICALLY STACKED LOW PRESSURE SYSTEM WILL TRACK FROM INTERIOR PORTIONS OF SOUTHERN NEW ENGLAND TO THE CANADIAN BORDER SUNDAY NIGHT. LEFTOVER PRECIPITATION WILL GENERALLY FALL AS LIGHT RAIN SHOWERS...THOUGH CRITICAL THICKNESSES WILL BECOME COLD ENOUGH TO SUPPORT SOME WET SNOW MIXING IN MAINLY OVER THE INTERIOR HIGH TERRAIN BEFORE IT ENDS AROUND DAYBREAK. CLOUDS WILL LINGER MONDAY AS THE UPPER FLOW REMAINS CYCLONIC AND AS LAPSE RATES STEEPEN. LOW LEVEL MOISTURE LEVELS WILL DRY OUT AS SURFACE WINDS INCREASE FROM THE WEST NORTHWEST DURING THE AFTERNOON. THE LAST SHORTWAVE ASSOCIATED WITH THE UPPER LEVEL LOW WILL SLIDE ACROSS EASTERN NEW ENGLAND TUESDAY MORNING. THIS WILL ALLOW ANTICYCLONIC FLOW TO DEVELOP DURING TUESDAY AFTERNOON. A DOWNSLOPING NORTHWEST FLOW SHOULD BOOST AFTERNOON TEMPERATURES WELL INTO THE 50S. SIMILAR DAYTIME TEMPERATURES SHOULD BE EXPERIENCED WEDNESDAY...THOUGH A WEAKER PRESSURE GRADIENT WILL ALLOW COOLING SEABREEZES TO DEVELOP NEAR THE COAST. HIGH CLOUDS WILL BEGIN TO INCREASE BY WEDNESDAY NIGHT...AS THE NEXT LOW PRESSURE SYSTEM DEEPENS ACROSS THE OHIO VALLEY. EXTENDED MODEL GUIDANCE INCLUDING THE GFS AND UKMET HAVE BACKED OFF ON THE TIMING OF PRECIPITATION LATE NEXT WEEK. THE CURRENT LOW PRESSURE SYSTEM OVER THE NORTHEAST WILL ACT TO SHUNT THE APPROACH OF THE NEXT SYSTEM LATE NEXT WEEK...WITH SLIGHTLY EXTENDED ANTICYCLONIC FLOW PERSISTING ACROSS THE REGION. IN ADDITION THE NEXT SYSTEM DEVELOPS THE "CUTOFF" FASTER THAN ITS PREDECESSOR. THUS HAVE REMOVED MENTION OF PRECIPITATION WEDNESDAY NIGHT AND HAVE FOCUSED THE STARTING TIME THURSDAY AFTERNOON. THIS APPEARS TO BE ANOTHER POTENTIALLY SIGNIFICANT RAINFALL EVENT FOR AREA RIVERS AND STREAMS. THEREFORE WILL NEED TO MONITOR THIS EVENT CLOSELY IN FUTURE MODEL RUNS. && .AVIATION... ALTHOUGH WE ARE SEEING SOME HOLES DEVELOP IN LOW CLOUD DECK OVER EASTERN TERMINALS...THIS IS EXPECTED TO BE SHORT LIVED AND IFR/LIFR CONDITIONS WILL PREVAIL TONIGHT. LOW LEVEL WIND SHEAR SHOULD PERSIST UNTIL 06-08Z WHEN LOW LEVEL JET EXITS COAST. CONDITIONS WILL IMPROVE TO MVFR SUN...OR EVEN VFR FOR A TIME...BUT ADDITIONAL SHOWERS SHOULD FORM SUN AFTERNOON WITH COLD POOL MOVING OVERHEAD. && .MARINE... GALE WARNINGS BEING POSTED FOR ALL WATERS. && .HYDROLOGY... WE CONTINUE TO MONITOR THE BAND OF HEAVY RAIN WHICH HAS REMAINED FOCUSED ON NJ...PA AND MUCH OF NY STATE THIS EVENING. WE ARE CURRENTLY IN THE DRY SLOT BUT ADDITIONAL RAINS ARE LIFTING N ONTO LONG ISLAND AND SHOULD FINALLY OVERSPREAD OUR WESTERN ZONES THIS EVENING. THERE IS STILL SOME QUESTION AS TO HOW THIS MOISTURE WILL INTERACT WITH TERRAIN...BUT HPC'S FORECAST OF UP TO 1.25" THERE SEEMS REASONABLE. RAINFALL DURING PAST 6 HRS (ENDING AT 00Z) HAS BEEN IMPRESSIVE ACROSS EASTERN PA WITH UP TO 2.48" AT MT POCONO. A QUICK LOOK AT 18Z MODELS SHOWS ONCE AGAIN GFS IS DOING A BETTER JOB...QUALITATIVELY...WITH ITS AXIS RUNNING THROUGH EASTERN PA AND INTO CENTRAL NY AND BARELY 0.25" INTO WESTERN CT. NAM HAD ITS AXIS A LITTLE TOO FAR E ACROSS NJ AND LOWER HUDSON VALLEY. WHAT MAY END UP OCCURRING IS A BAND OF HEAVY RAIN PUSHES THROUGH SOUTHERN NEW ENGLAND WITHIN A 4 TO 6 HOUR WINDOW TONIGHT...BRINGING A QUICK DELUGE OF 0.75 TO 1.50" TO WESTERN ZONES (LESS FARTHER E) AND EXITING COAST AFTER MIDNIGHT...SIMILAR TO WHAT IS DEPICTED BY GFS. 21Z RUC FOLLOWS THIS IDEA AS WELL AND OUR 10KM WORKSTATION ETA AGREES TOO...BUT IS EVEN SLOWER IN BRINGING HEAVIER RAIN THROUGH. IMPACT ON RIVERS AND STREAMS IS A TOUGH CALL AS WELL...SINCE THEY HAVE HAD TIME TO RECOVER FROM THE HEAVY RAIN THAT FELL EARLIER TODAY. A QUICK REVIEW OF HYDROGRAPHS SHOW MANY OF THE FLASHIER LOCATIONS HAVE ALREADY CRESTED AND HAVE BEGUN TO RECEDE...BUT ADDITIONAL RAINFALL IN A SHORT PERIOD TONIGHT WILL BRING THEM BACK UP AGAIN QUICKLY. WE WILL LEAVE THE FLOOD WATCH FOR SMALL STREAMS IN EFFECT. WE ARE COORDINATING WITH NERFC FOR THE EVENING UPDATE ON LARGER RIVERS IN SOUTHERN NEW ENGLAND. FLOODING STILL APPEARS LIKELY FOR MOST OF THE LARGER RIVERS...BUT CRESTS MAY NEED TO BE ADJUSTED DOWNWARD SLIGHTLY SINCE WE WILL PROBABLY SEE LOWER RAINFALL AMOUNTS. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...WIND ADVISORY FOR CTZ002>004 UNTIL 6 AM SUNDAY. ...FLOOD WATCH FOR CTZ002>004 UNTIL 7 PM SUNDAY. MA...WIND ADVISORY FOR MAZ011-012>024 UNTIL 6 AM SUNDAY. ...FLOOD WATCH FOR MAZ002>021-026 UNTIL 7 PM SUNDAY. ...WIND ADVISORY FOR MAZ022>024 FROM 6 PM SATURDAY TO 7 AM SUNDAY. NH...FLOOD WATCH FOR NHZ011-012-015 UNTIL 7 PM SUNDAY. RI...WIND ADVISORY FOR RIZ001>008 UNTIL 6 AM SUNDAY. ...FLOOD WATCH FOR RIZ001>007 UNTIL 7 PM SUNDAY. MARINE...GALE WARNING TONIGHT ALL WATERS. && $$ SHORT TERM...JWD/AED AVIATION...JWD HYDROLOGY...JWD/DRV ma AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE TAUNTON MA 840 PM EST SAT APR 2 2005 .SHORT TERM (REST OF TONIGHT THROUGH SUNDAY)... WE ARE STARTING TO SEE AXIS OF HEAVIEST RAIN SHIFT INTO SOUTHERN NEW ENGLAND. IT EXTENDS IN AN ARC FROM THE MOHAWK AND HUDSON VALLEYS IN NEW YORK STATE INTO WESTERN CT...AND RADAR TRENDS SUGGEST THIS AXIS WILL REMAIN IN A NW/SE ORIENTATION FOR THE NEXT FEW HOURS BEFORE ALIGNING MORE W/E. THIS SHOULD BRING HEAVY RAINFALL TO MUCH OF THE LOWER CT VALLEY THROUGH MIDNIGHT...INCLUDING HARTFORD AND WESTFIELD. ADDITIONAL ELEMENTS LIFTING N TOWARD LONG ISLAND SHOULD BECOME ENTRAINED ALONG THIS AXIS AS WELL. FARTHER E...IT IS STILL A TOUGH CALL AS TO HOW FAST THE HEAVIER RAIN ARRIVES...BUT WE DO EXPECT THAT TO OCCUR AROUND MIDNIGHT. FROM THE 730 PM UPDATE... WE CONTINUE TO MONITOR THE BAND OF HEAVY RAIN WHICH HAS REMAINED FOCUSED ON NJ...PA AND MUCH OF NY STATE THIS EVENING. WE ARE CURRENTLY IN THE DRY SLOT BUT ADDITIONAL RAINS ARE LIFTING N ONTO LONG ISLAND AND SHOULD FINALLY OVERSPREAD OUR WESTERN ZONES THIS EVENING. THERE IS STILL SOME QUESTION AS TO HOW THIS MOISTURE WILL INTERACT WITH TERRAIN...BUT HPC'S FORECAST OF UP TO 1.25" THERE SEEMS REASONABLE. RAINFALL DURING PAST 6 HRS (ENDING AT 00Z) HAS BEEN IMPRESSIVE ACROSS EASTERN PA WITH UP TO 2.48" AT MT POCONO. A QUICK LOOK AT 18Z MODELS SHOWS ONCE AGAIN GFS IS DOING A BETTER JOB...QUALITATIVELY...WITH ITS AXIS RUNNING THROUGH EASTERN PA AND INTO CENTRAL NY AND BARELY 0.25" INTO WESTERN CT. NAM HAD ITS AXIS A LITTLE TOO FAR E ACROSS NJ AND LOWER HUDSON VALLEY. WHAT MAY END UP OCCURRING IS A BAND OF HEAVY RAIN PUSHES THROUGH SOUTHERN NEW ENGLAND WITHIN A 4 TO 6 HOUR WINDOW TONIGHT...BRINGING A QUICK DELUGE OF 0.75 TO 1.50" TO WESTERN ZONES (LESS FARTHER E) AND EXITING COAST AFTER MIDNIGHT...SIMILAR TO WHAT IS DEPICTED BY GFS. 21Z RUC FOLLOWS THIS IDEA AS WELL AND OUR 10KM WORKSTATION ETA AGREES TOO...BUT IS EVEN SLOWER IN BRINGING HEAVIER RAIN THROUGH. IMPACT ON RIVERS AND STREAMS IS A TOUGH CALL AS WELL...SINCE THEY HAVE HAD TIME TO RECOVER FROM THE HEAVY RAIN THAT FELL EARLIER TODAY. A QUICK REVIEW OF HYDROGRAPHS SHOW MANY OF THE FLASHIER LOCATIONS HAVE ALREADY CRESTED AND HAVE BEGUN TO RECEDE...BUT ADDITIONAL RAINFALL IN A SHORT PERIOD TONIGHT WILL BRING THEM BACK UP AGAIN QUICKLY. WE WILL LEAVE THE FLOOD WATCH FOR SMALL STREAMS IN EFFECT. WE ARE COORDINATING WITH NERFC FOR THE EVENING UPDATE ON LARGER RIVERS IN SOUTHERN NEW ENGLAND. FLOODING STILL APPEARS LIKELY FOR MOST OF THE LARGER RIVERS...BUT CRESTS MAY NEED TO BE ADJUSTED DOWNWARD SLIGHTLY SINCE WE WILL PROBABLY SEE LOWER RAINFALL AMOUNTS. ALSO OF IMPORTANCE...WE HAVE SEEN STRONG WINDS MATERIALIZE IN NYC AREA DURING PAST FEW HOURS AND GUSTS MAY PICK UP HERE AS HEAVIER RAIN ARRIVES...ESPECIALLY IN WARM SECTOR WHERE TEMPERATURES HAVE JUMPED INTO 50S. WE DON'T HAVE ENOUGH CONFIDENCE TO EXPAND WIND ADVISORY FARTHER INLAND...BUT WE ARE KEEPING A CLOSE EYE ON IT. FORECASTS WILL BE UPDATED LATER THIS EVENING TO ACCOUNT FOR CURRENT CONDITIONS. && .AVIATION... ALTHOUGH WE ARE SEEING SOME HOLES DEVELOP IN LOW CLOUD DECK OVER EASTERN TERMINALS...THIS IS EXPECTED TO BE SHORT LIVED AND IFR/LIFR CONDITIONS WILL PREVAIL TONIGHT. LOW LEVEL WIND SHEAR SHOULD PERSIST UNTIL 06-08Z WHEN LOW LEVEL JET EXITS COAST. CONDITIONS WILL IMPROVE TO MVFR SUN...OR EVEN VFR FOR A TIME...BUT ADDITIONAL SHOWERS SHOULD FORM SUN AFTERNOON WITH COLD POOL MOVING OVERHEAD. && .PREVIOUS DISCUSSION... (ISSUED 430 PM EST SAT APR 2 2005) ..NEXT ROUND OF HEAVY RAIN ARRIVES THIS EVENING... SHORT TERM (TONIGHT AND SUNDAY)... WATCHING NEXT AREA OF HEAVY RAIN OVER EASTERN PA/NJ AND DE AS IT TAKES AIM AT SOUTHERN NEW ENGLAND. 12Z GFS CONTINUES ITS EARLIER TREND OF DEPICTING A BREAK IN THE RAIN THIS AFTERNOON BEFORE THE NEXT ROUND OF HEAVY RAIN APPROACHES FROM THE SOUTH THIS EVENING. 06 HOUR QPF AND OMEGA FIELDS FROM THE 12Z GFS VERIFYING AT 18Z APPEARS TO HAVE A BETTER HANDLE THAN THE NAM/ETA ON THE CONFIGURATION OF THE HEAVY RAIN OVER EASTERN PA/NJ AND DE. THEREFORE...WE FOLLOWED THE 12Z GFS CLOSELY...ESPECIALLY FOR TIMING THIS NEXT SLUG OF HEAVY RAIN. GFS AND NAM/ETA ONLY GIVE THE REGION ANOTHER 1 INCH OF QPF THIS EVENING AND OVERNIGHT. WE ARE FAIRLY CONFIDENT THIS IN UNDERDONE...AS SURFACE OBS IN THE HEAVY RAIN TO OUR SOUTH ARE INDICATING HOURLY RAINFALL RATES OF 0.30 TO 0.40. IN ADDITION...12Z GFS HAS A POTENT 75 KT SE 850 MB JET ASSOCIATED WITH THIS HEAVY RAIN BAND. SO WE BASICALLY INCREASED THE 12Z GFS QPF TO 1.5 BASIN WIDE THIS EVENING AND OVERNIGHT...WITH ISOLATED 2.0 ACROSS THE FAVORED UPSLOPE REGIONS (EAST FACING WITH STRONG SE INFLOW) OF CT...RI...EAST SLOPES OF BERKS...WORCESTER HILLS AND INTO THE MONADNOCKS. BULK OF THE HEAVY RAIN BEGINS TO TAPER OFF AFTER MIDNIGHT FROM SOUTHWEST TO NORTHEAST...AS MID LEVEL JET EXITS INTO THE GULF OF ME. AS FOR TEMPS...PREFER THE COOLER FWC NUMBERS AS THE WARM AIR WILL LIKELY BE DELAYED UNTIL THE SURFACE LOW MOVES NORTH OF OUR LATITUDE. MODELS SUGGEST THIS WILL HAPPEN LATE SUNDAY...HOWEVER IT COULD BE EVEN LATER AS SYSTEM IS VERTICALLY STACKED. SO...EXPECT TEMPS TO HOLD IN THE COOL 40S SUNDAY...ALONG WITH SCATTERED SHOWERS AROUND. LONG TERM (SUNDAY NIGHT THROUGH SATURDAY)... A VERTICALLY STACKED LOW PRESSURE SYSTEM WILL TRACK FROM INTERIOR PORTIONS OF SOUTHERN NEW ENGLAND TO THE CANADIAN BORDER SUNDAY NIGHT. LEFTOVER PRECIPITATION WILL GENERALLY FALL AS LIGHT RAIN SHOWERS...THOUGH CRITICAL THICKNESSES WILL BECOME COLD ENOUGH TO SUPPORT SOME WET SNOW MIXING IN MAINLY OVER THE INTERIOR HIGH TERRAIN BEFORE IT ENDS AROUND DAYBREAK. CLOUDS WILL LINGER MONDAY AS THE UPPER FLOW REMAINS CYCLONIC AND AS LAPSE RATES STEEPEN. LOW LEVEL MOISTURE LEVELS WILL DRY OUT AS SURFACE WINDS INCREASE FROM THE WEST NORTHWEST DURING THE AFTERNOON. THE LAST SHORTWAVE ASSOCIATED WITH THE UPPER LEVEL LOW WILL SLIDE ACROSS EASTERN NEW ENGLAND TUESDAY MORNING. THIS WILL ALLOW ANTICYCLONIC FLOW TO DEVELOP DURING TUESDAY AFTERNOON. A DOWNSLOPING NORTHWEST FLOW SHOULD BOOST AFTERNOON TEMPERATURES WELL INTO THE 50S. SIMILAR DAYTIME TEMPERATURES SHOULD BE EXPERIENCED WEDNESDAY...THOUGH A WEAKER PRESSURE GRADIENT WILL ALLOW COOLING SEABREEZES TO DEVELOP NEAR THE COAST. HIGH CLOUDS WILL BEGIN TO INCREASE BY WEDNESDAY NIGHT...AS THE NEXT LOW PRESSURE SYSTEM DEEPENS ACROSS THE OHIO VALLEY. EXTENDED MODEL GUIDANCE INCLUDING THE GFS AND UKMET HAVE BACKED OFF ON THE TIMING OF PRECIPITATION LATE NEXT WEEK. THE CURRENT LOW PRESSURE SYSTEM OVER THE NORTHEAST WILL ACT TO SHUNT THE APPROACH OF THE NEXT SYSTEM LATE NEXT WEEK...WITH SLIGHTLY EXTENDED ANTICYCLONIC FLOW PERSISTING ACROSS THE REGION. IN ADDITION THE NEXT SYSTEM DEVELOPS THE "CUTOFF" FASTER THAN ITS PREDECESSOR. THUS HAVE REMOVED MENTION OF PRECIPITATION WEDNESDAY NIGHT AND HAVE FOCUSED THE STARTING TIME THURSDAY AFTERNOON. THIS APPEARS TO BE ANOTHER POTENTIALLY SIGNIFICANT RAINFALL EVENT FOR AREA RIVERS AND STREAMS. THEREFORE WILL NEED TO MONITOR THIS EVENT CLOSELY IN FUTURE MODEL RUNS. AVIATION... LLWS UNTIL ABOUT 06-08Z...THEN LOW AND MID LEVEL JET EXITS INTO THE GULF OF ME. WIDESPREAD IFR CONDITIONS TONIGHT...WITH CONDITIONS IMPROVING TO MVFR SUNDAY. MARINE... IN THE SHORT RANGE...MARGINAL SOUTHEAST GALES (34 KT)TONIGHT...THEN WINDS EASING TOWARD MORNING. WINDS WILL REMAIN FROM THE SOUTHEAST SUN. IN THE LONGER TERM...SMALL CRAFT ADVISORY SEAS WILL PERSIST MONDAY DUE TO LEFTOVER SOUTHERLY SWELL. SOUTHERLY SWELLS WILL REDEVELOP THURSDAY AHEAD OF THE NEXT SIGNIFICANT WEATHER SYSTEM. HYDROLOGY... FLOOD WATCH CONTINUES THROUGH SUNDAY. NEXT ROUND OF HEAVY RAIN TO YIELD AN ADDITIONAL 1 TO 2 INCHES OF QPF. THIS COMBINED WITH HEAVY RAIN FROM THIS MORNING...SNOW MELT ACROSS NORTHERN/CENTRAL NEW ENGLAND AND INITIAL HIGH FLOWS WILL CONTINUE THE POTENTIAL OF SIGNIFICANT SMALL STREAM AND MAIN STEM RIVER FLOODING. BELIEVE MOST OF REGION AT RISK...BUT ESPECIALLY SO CONNECTICUT RIVER BASIN WHERE ANTICIPATE MAY SEE HIGHER QPF VALUES (AN ADDITIONAL 2 INCHES POSSIBLE). IN ADDITION...EXPECT WIDESPREAD STREET FLOODING AND CONSIDERABLE BASEMENT FLOODING WITH HIGH WATER TABLES. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...FLOOD WATCH FOR CTZ002>004 UNTIL 7 PM SUNDAY. MA...FLOOD WATCH FOR MAZ002>021-026 UNTIL 7 PM SUNDAY. ...WIND ADVISORY FOR MAZ022>024 FROM 6 PM SATURDAY TO 7 AM SUNDAY. NH...FLOOD WATCH FOR NHZ011-012-015 UNTIL 7 PM SUNDAY. RI...FLOOD WATCH FOR RIZ001>007 UNTIL 7 PM SUNDAY. ...WIND ADVISORY FOR RIZ008 FROM 6 PM SATURDAY TO 7 AM SUNDAY. MARINE...GALE WARNING TONIGHT ALL WATERS EXCEPT SCA BOSTON HARBOR. && $$ SHORT TERM...JWD/AED AVIATION...JWD HYDROLOGY...JWD/DRV ma AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE TAUNTON MA 730 PM EST SAT APR 2 2005 .SHORT TERM (REST OF TONIGHT THROUGH SUNDAY)... WE CONTINUE TO MONITOR THE BAND OF HEAVY RAIN WHICH HAS REMAINED FOCUSED ON NJ...PA AND MUCH OF NY STATE THIS EVENING. WE ARE CURRENTLY IN THE DRY SLOT BUT ADDITIONAL RAINS ARE LIFTING N ONTO LONG ISLAND AND SHOULD FINALLY OVERSPREAD OUR WESTERN ZONES THIS EVENING. THERE IS STILL SOME QUESTION AS TO HOW THIS MOISTURE WILL INTERACT WITH TERRAIN...BUT HPC'S FORECAST OF UP TO 1.25" THERE SEEMS REASONABLE. RAINFALL DURING PAST 6 HRS (ENDING AT 00Z) HAS BEEN IMPRESSIVE ACROSS EASTERN PA WITH UP TO 2.48" AT MT POCONO. A QUICK LOOK AT 18Z MODELS SHOWS ONCE AGAIN GFS IS DOING A BETTER JOB...QUALITATIVELY...WITH ITS AXIS RUNNING THROUGH EASTERN PA AND INTO CENTRAL NY AND BARELY 0.25" INTO WESTERN CT. NAM HAD ITS AXIS A LITTLE TOO FAR E ACROSS NJ AND LOWER HUDSON VALLEY. WHAT MAY END UP OCCURRING IS A BAND OF HEAVY RAIN PUSHES THROUGH SOUTHERN NEW ENGLAND WITHIN A 4 TO 6 HOUR WINDOW TONIGHT...BRINGING A QUICK DELUGE OF 0.75 TO 1.50" TO WESTERN ZONES (LESS FARTHER E) AND EXITING COAST AFTER MIDNIGHT...SIMILAR TO WHAT IS DEPICTED BY GFS. 21Z RUC FOLLOWS THIS IDEA AS WELL AND OUR 10KM WORKSTATION ETA AGREES TOO...BUT IS EVEN SLOWER IN BRINGING HEAVIER RAIN THROUGH. IMPACT ON RIVERS AND STREAMS IS A TOUGH CALL AS WELL...SINCE THEY HAVE HAD TIME TO RECOVER FROM THE HEAVY RAIN THAT FELL EARLIER TODAY. A QUICK REVIEW OF HYDROGRAPHS SHOW MANY OF THE FLASHIER LOCATIONS HAVE ALREADY CRESTED AND HAVE BEGUN TO RECEDE...BUT ADDITIONAL RAINFALL IN A SHORT PERIOD TONIGHT WILL BRING THEM BACK UP AGAIN QUICKLY. WE WILL LEAVE THE FLOOD WATCH FOR SMALL STREAMS IN EFFECT. WE ARE COORDINATING WITH NERFC FOR THE EVENING UPDATE ON LARGER RIVERS IN SOUTHERN NEW ENGLAND. FLOODING STILL APPEARS LIKELY FOR MOST OF THE LARGER RIVERS...BUT CRESTS MAY NEED TO BE ADJUSTED DOWNWARD SLIGHTLY SINCE WE WILL PROBABLY SEE LOWER RAINFALL AMOUNTS. ALSO OF IMPORTANCE...WE HAVE SEEN STRONG WINDS MATERIALIZE IN NYC AREA DURING PAST FEW HOURS AND GUSTS MAY PICK UP HERE AS HEAVIER RAIN ARRIVES...ESPECIALLY IN WARM SECTOR WHERE TEMPERATURES HAVE JUMPED INTO 50S. WE DON'T HAVE ENOUGH CONFIDENCE TO EXPAND WIND ADVISORY FARTHER INLAND...BUT WE ARE KEEPING A CLOSE EYE ON IT. FORECASTS WILL BE UPDATED LATER THIS EVENING TO ACCOUNT FOR CURRENT CONDITIONS. && .AVIATION... ALTHOUGH WE ARE SEEING SOME HOLES DEVELOP IN LOW CLOUD DECK OVER EASTERN TERMINALS...THIS IS EXPECTED TO BE SHORT LIVED AND IFR/LIFR CONDITIONS WILL PREVAIL TONIGHT. LOW LEVEL WIND SHEAR SHOULD PERSIST UNTIL 06-08Z WHEN LOW LEVEL JET EXITS COAST. CONDITIONS WILL IMPROVE TO MVFR SUN...OR EVEN VFR FOR A TIME...BUT ADDITIONAL SHOWERS SHOULD FORM SUN AFTERNOON WITH COLD POOL MOVING OVERHEAD. && .PREVIOUS DISCUSSION... (ISSUED 430 PM EST SAT APR 2 2005) ..NEXT ROUND OF HEAVY RAIN ARRIVES THIS EVENING... SHORT TERM (TONIGHT AND SUNDAY)... WATCHING NEXT AREA OF HEAVY RAIN OVER EASTERN PA/NJ AND DE AS IT TAKES AIM AT SOUTHERN NEW ENGLAND. 12Z GFS CONTINUES ITS EARLIER TREND OF DEPICTING A BREAK IN THE RAIN THIS AFTERNOON BEFORE THE NEXT ROUND OF HEAVY RAIN APPROACHES FROM THE SOUTH THIS EVENING. 06 HOUR QPF AND OMEGA FIELDS FROM THE 12Z GFS VERIFYING AT 18Z APPEARS TO HAVE A BETTER HANDLE THAN THE NAM/ETA ON THE CONFIGURATION OF THE HEAVY RAIN OVER EASTERN PA/NJ AND DE. THEREFORE...WE FOLLOWED THE 12Z GFS CLOSELY...ESPECIALLY FOR TIMING THIS NEXT SLUG OF HEAVY RAIN. GFS AND NAM/ETA ONLY GIVE THE REGION ANOTHER 1 INCH OF QPF THIS EVENING AND OVERNIGHT. WE ARE FAIRLY CONFIDENT THIS IN UNDERDONE...AS SURFACE OBS IN THE HEAVY RAIN TO OUR SOUTH ARE INDICATING HOURLY RAINFALL RATES OF 0.30 TO 0.40. IN ADDITION...12Z GFS HAS A POTENT 75 KT SE 850 MB JET ASSOCIATED WITH THIS HEAVY RAIN BAND. SO WE BASICALLY INCREASED THE 12Z GFS QPF TO 1.5 BASIN WIDE THIS EVENING AND OVERNIGHT...WITH ISOLATED 2.0 ACROSS THE FAVORED UPSLOPE REGIONS (EAST FACING WITH STRONG SE INFLOW) OF CT...RI...EAST SLOPES OF BERKS...WORCESTER HILLS AND INTO THE MONADNOCKS. BULK OF THE HEAVY RAIN BEGINS TO TAPER OFF AFTER MIDNIGHT FROM SOUTHWEST TO NORTHEAST...AS MID LEVEL JET EXITS INTO THE GULF OF ME. AS FOR TEMPS...PREFER THE COOLER FWC NUMBERS AS THE WARM AIR WILL LIKELY BE DELAYED UNTIL THE SURFACE LOW MOVES NORTH OF OUR LATITUDE. MODELS SUGGEST THIS WILL HAPPEN LATE SUNDAY...HOWEVER IT COULD BE EVEN LATER AS SYSTEM IS VERTICALLY STACKED. SO...EXPECT TEMPS TO HOLD IN THE COOL 40S SUNDAY...ALONG WITH SCATTERED SHOWERS AROUND. LONG TERM (SUNDAY NIGHT THROUGH SATURDAY)... A VERTICALLY STACKED LOW PRESSURE SYSTEM WILL TRACK FROM INTERIOR PORTIONS OF SOUTHERN NEW ENGLAND TO THE CANADIAN BORDER SUNDAY NIGHT. LEFTOVER PRECIPITATION WILL GENERALLY FALL AS LIGHT RAIN SHOWERS...THOUGH CRITICAL THICKNESSES WILL BECOME COLD ENOUGH TO SUPPORT SOME WET SNOW MIXING IN MAINLY OVER THE INTERIOR HIGH TERRAIN BEFORE IT ENDS AROUND DAYBREAK. CLOUDS WILL LINGER MONDAY AS THE UPPER FLOW REMAINS CYCLONIC AND AS LAPSE RATES STEEPEN. LOW LEVEL MOISTURE LEVELS WILL DRY OUT AS SURFACE WINDS INCREASE FROM THE WEST NORTHWEST DURING THE AFTERNOON. THE LAST SHORTWAVE ASSOCIATED WITH THE UPPER LEVEL LOW WILL SLIDE ACROSS EASTERN NEW ENGLAND TUESDAY MORNING. THIS WILL ALLOW ANTICYCLONIC FLOW TO DEVELOP DURING TUESDAY AFTERNOON. A DOWNSLOPING NORTHWEST FLOW SHOULD BOOST AFTERNOON TEMPERATURES WELL INTO THE 50S. SIMILAR DAYTIME TEMPERATURES SHOULD BE EXPERIENCED WEDNESDAY...THOUGH A WEAKER PRESSURE GRADIENT WILL ALLOW COOLING SEABREEZES TO DEVELOP NEAR THE COAST. HIGH CLOUDS WILL BEGIN TO INCREASE BY WEDNESDAY NIGHT...AS THE NEXT LOW PRESSURE SYSTEM DEEPENS ACROSS THE OHIO VALLEY. EXTENDED MODEL GUIDANCE INCLUDING THE GFS AND UKMET HAVE BACKED OFF ON THE TIMING OF PRECIPITATION LATE NEXT WEEK. THE CURRENT LOW PRESSURE SYSTEM OVER THE NORTHEAST WILL ACT TO SHUNT THE APPROACH OF THE NEXT SYSTEM LATE NEXT WEEK...WITH SLIGHTLY EXTENDED ANTICYCLONIC FLOW PERSISTING ACROSS THE REGION. IN ADDITION THE NEXT SYSTEM DEVELOPS THE "CUTOFF" FASTER THAN ITS PREDECESSOR. THUS HAVE REMOVED MENTION OF PRECIPITATION WEDNESDAY NIGHT AND HAVE FOCUSED THE STARTING TIME THURSDAY AFTERNOON. THIS APPEARS TO BE ANOTHER POTENTIALLY SIGNIFICANT RAINFALL EVENT FOR AREA RIVERS AND STREAMS. THEREFORE WILL NEED TO MONITOR THIS EVENT CLOSELY IN FUTURE MODEL RUNS. AVIATION... LLWS UNTIL ABOUT 06-08Z...THEN LOW AND MID LEVEL JET EXITS INTO THE GULF OF ME. WIDESPREAD IFR CONDITIONS TONIGHT...WITH CONDITIONS IMPROVING TO MVFR SUNDAY. MARINE... IN THE SHORT RANGE...MARGINAL SOUTHEAST GALES (34 KT)TONIGHT...THEN WINDS EASING TOWARD MORNING. WINDS WILL REMAIN FROM THE SOUTHEAST SUN. IN THE LONGER TERM...SMALL CRAFT ADVISORY SEAS WILL PERSIST MONDAY DUE TO LEFTOVER SOUTHERLY SWELL. SOUTHERLY SWELLS WILL REDEVELOP THURSDAY AHEAD OF THE NEXT SIGNIFICANT WEATHER SYSTEM. HYDROLOGY... FLOOD WATCH CONTINUES THROUGH SUNDAY. NEXT ROUND OF HEAVY RAIN TO YIELD AN ADDITIONAL 1 TO 2 INCHES OF QPF. THIS COMBINED WITH HEAVY RAIN FROM THIS MORNING...SNOW MELT ACROSS NORTHERN/CENTRAL NEW ENGLAND AND INITIAL HIGH FLOWS WILL CONTINUE THE POTENTIAL OF SIGNIFICANT SMALL STREAM AND MAIN STEM RIVER FLOODING. BELIEVE MOST OF REGION AT RISK...BUT ESPECIALLY SO CONNECTICUT RIVER BASIN WHERE ANTICIPATE MAY SEE HIGHER QPF VALUES (AN ADDITIONAL 2 INCHES POSSIBLE). IN ADDITION...EXPECT WIDESPREAD STREET FLOODING AND CONSIDERABLE BASEMENT FLOODING WITH HIGH WATER TABLES. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...FLOOD WATCH FOR CTZ002>004 UNTIL 7 PM SUNDAY. MA...FLOOD WATCH FOR MAZ002>021-026 UNTIL 7 PM SUNDAY. ...WIND ADVISORY FOR MAZ022>024 FROM 6 PM SATURDAY TO 7 AM SUNDAY. NH...FLOOD WATCH FOR NHZ011-012-015 UNTIL 7 PM SUNDAY. RI...FLOOD WATCH FOR RIZ001>007 UNTIL 7 PM SUNDAY. ...WIND ADVISORY FOR RIZ008 FROM 6 PM SATURDAY TO 7 AM SUNDAY. MARINE...GALE WARNING TONIGHT ALL WATERS EXCEPT SCA BOSTON HARBOR. && $$ SHORT TERM...JWD/AED AVIATION...JWD HYDROLOGY...JWD/DRV ma AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 740 PM EST SAT APR 2 2005 .UPDATE... LOOKING AT RADAR TRENDS FROM DTX 88D AND CANADIAN EXETER RADAR...IT APPEARS UNLIKELY THAT THE PRECIPITATION SHIELD WHICH HAS RETREATED EAST WILL BULGE BACK WEST INTO FORECAST AREA. THUS...A DRY REST OF TONIGHT THROUGHOUT. HAVE TWEAKED SKY GRIDS FOR CURRENT CLEARING TRENDS AND LOWERED LAND WINDS SOMEWHAT TONIGHT AS WELL...AS CLEAR SKIES ALREADY SEEN DECOUPLING THE FLOW AND THUS LOWERING REPORTED WINDS. ZONE FORECAST PACKAGE WILL BE UPDATED SHORTLY. && .AVIATION...ISSUED 655 PM EST SAT BARRING ANY UNEXPECTED WESTWARD BULGING OF PRECIPITATION SHIELD FROM EASTERN SYSTEM...AM NO LONGER EXPECTING ANY MORE PRECIPITATION OR NON VFR CEILINGS OVER TAF SITES THIS EVENING...AND THIS IS ESPECIALLY SO THROUGH THE OVERNIGHT AND SUNDAY TIME FRAME AS DRY AIR AND SUBSIDENCE REIGN...NO RESTRICTION TO VISIBILITY EXPECTED EITHER. EXPECT SLOW DROPPING OFF OF THE WINDS TONIGHT...ESPECIALLY GUSTINESS...AS CLEARING SKIES PROMOTE DECOUPLING/STABILIZATION AND INHIBIT MIXING. STILL BEING AFFECTED SUNDAY IN FAIRLY BRISK CYCLONIC FLOW AROUND EASTERN SYSTEM...THOUGH...AND DIURNAL HEATING WILL AGAIN DEEPEN MIXING LAYER AND PROMOTE GUSTINESS BY AFTERNOON. && .SHORT TERM...TONIGHT AND SUNDAY...ISSUED 355 PM EST SAT 12Z RAOBS/WATER VAPOR LOOP SHOW AN UPPER LOW MOVING THROUGH THE TENNESSEE/OHIO VALLEYS...WITH THE SURFACE LOW REDEVELOPING ALONG THE MID ATLANTIC COAST. REGIONAL RADARS SHOW PERSISTENT PRECIP BAND ACROSS SOUTHEASTERN ONTARIO...STILL BRUSHING THE FAR SOUTHEAST CWA. VIS SATELLITE SHOWS CLEARING UPSTREAM...WITH ONLY THINNING HIGH CLOUDS ACROSS THE SAGINAW VALLEY. MAIN FOCUS FOR THE FIRST 24 HOURS WILL BE WITH INITIAL PRECIP. 18Z RUC IS A BIT SLOWER THAN THE 12Z/15Z RUNS TAKING THE BEST MID-LEVEL DEFORMATION THROUGH THE CWA...AND CONSEQUENTLY HOLD ON TO LIFT ACROSS THE FAR SOUTHEAST CWA FOR LONGER. REGIONAL RADARS HAVE SHOWN A SLIGHT REORIENTATION WITH BETTER LIFT DEVELOPING FARTHER NORTH ACROSS ONTARIO AS THE VORT CENTER SWINGS BACK AROUND THE CUTOFF LOW. WILL HOLD ON TO CATEGORICAL POPS INTO THE EARLY EVENING ACROSS THE VERY FAR SOUTHEAST CWA...MAINLY MACOMB/ST CLAIR BASED ON RECENT RADAR TRENDS. AS FAR A PRECIP TYPE...RECENT TAMDAR SOUNDINGS CONTINUE TO SHOW FREEZING LEVELS GENERALLY 1.6-18.KFT ACROSS THE SOUTHEAST CWA. THERE HAVE BEEN MORE SNOW REPORTS...ESPECIALLY FROM THE PHN/YZR AREA...CORRESPONDING WITH STRONGER RADAR RETURNS/HEAVIER PRECIP RATES. WILL ALLOW FOR MORE SNOW ACROSS ST CLAIR COUNTY...AND KEEP IT JUST A CHANCE OF SNOW MIXED IN ACROSS MACOMB. 1000-850MB TRAJECTORIES SUPPORT A SLOWER CLEARING TREND...AT LEAST ACROSS THE EASTERN CWA. WITH CLOUD SHIELD ALREADY PRETTY THIN ACROSS THE NORTHWEST...SHOULD SEE CLEARING PRETTY EARLY IN THE TRI CITIES. ACTUALLY WILL START MIDLAND/BAY AS MOSTLY CLEAR. DEEPER MOISTURE WILL CONTINUE TO PULL EAST AS THE SYSTEM MOVE TO EASTERN PENNSYLVANIA TONIGHT AND FURTHER WRAPS UP...ALLOWING THE CLEARING SKIES TO WORK THROUGH THE CWA. GRADIENT STAYS PRETTY STRONG THROUGH SUNDAY...WITH A PRETTY WELL MIXED BOUNDARY LAYER THROUGH THE NIGHT LEADING TO SOME CONTINUED GUSTINESS. NOT MUCH OF A TEMPERATURE GRADIENT ACROSS THE STATE WITH LITTLE THERMAL ADVECTION BEHIND THIS SYSTEM...BUT WILL KEEP LOWS A COUPLE DEGREES COLDER ACROSS THE SAGINAW VALLEY WITH EARLIER CLEARING. THERE SHOULD BE A GOOD DEAL OF SUNSHINE ON SUNDAY. HOWEVER...BOTH NAM/GFS TRY TO BRING IN THE MID-LEVEL DECK FROM MINNESOTA. UPPER FLOW BECOMES MORE CONFLUENT ACROSS THE STATE BETWEEN SHORTWAVE RIDGE OVER THE WESTERN GREAT LAKES AND LOW OVER THE NORTHEAST. THIS MID/UPPER LEVEL MOISTURE MAY HAVE A DIFFICULT TIME MAKING IT THIS FAR EAST...BUT THERE SHOULD BE ENOUGH CLOUDS AROUND FOR MOSTLY SUNNY AS OPPOSED TO PLAIN SUNNY SKIES. FORECAST SOUNDINGS SHOW US MIXING UP TO 850MB...WHERE TEMPERATURES HOVER FROM -2C TO 0C. WITH GOOD APRIL INSOLATION...THIS SHOULD HELP US CLIMB BACK INTO THE 50S. && .LONG TERM...MONDAY THROUGH SATURDAY...ISSUED 355 PM EST SAT INITIAL PROBLEMS IN THE LONG TERM WILL BE JUST HOW MILD TO GO WITH TEMPERATURES AS CURRENT SYSTEM WORKS SLOWLY OFF TO THE NORTHEAST & WEST/NORTHWEST FLOW SETS IN BEHIND IT. THEREAFTER...SOUTHERLY FLOW GRADUALLY SETS UP AS NEXT WEATHER MAKER DIGS INTO THE OHIO VALLEY BY WEDNESDAY AND THURSDAY. MODELS ALL SHOW A VERY VIGOROUS UPPER LOW DEVELOPING IN THE AREA BY MID/LATE WEEK...BUT DIFFER RATHER SIGNIFICANTLY WITH EACH OTHER AND FROM RUN TO RUN. TREND...HOWEVER...SUGGESTS THAT AN EXTENDED PERIOD OF RAIN IS ON TAP DURING THE EXTENDED FORECAST...OR AT THE VERY LEAST...A 2 OR 3 DAY PERIOD IN WHICH VARIOUS "WAVES" OF RAIN AND EMBEDDED THUNDER...WILL ROTATE THROUGH THE AREA. IN TERMS OF TEMPERATURES...WILL MAKE SOME ADJUSTMENTS TO LAKESHORE TEMPERATURES ON DAYS IN WHICH AN ONSHORE FLOW SEEMS MORE LIKELY. NAMELY ON MONDAY AS LIGHT...NORTHWEST FLOW SHOULD BE DOMINATED BY LAKE BREEZE BY AFTERNOON. THEN...AS AFOREMENTIONED SYSTEM WRAPS UP TO OUR SOUTHWEST...OVERALL SYNOPTIC FLOW WILL TEND TO A SOLID SOUTHEASTERLY DIRECTION. HENCE...WARMEST IN THE WEST CENTRAL CWA AND COLDEST OFF LAKE ERIE/LAKE HURON. TREND WILL BE FOR MILD WEATHER INTO THE WEDNESDAY AND PERHAPS THURSDAY TIMEFRAME...DEPENDING ON JUST HOW/WHERE THIS UPPER LOW PRESSURE SYSTEM EVOLVES. THEREAFTER...EXPECT A COOL DOWN FOR THE UPCOMING WEEKEND AS CORE OF SYSTEM (AND ASSOCIATED COLDER AIR) DRIFTS THROUGH OR VERY NEAR THE AREA...AND COLDER AIR EVENTUALLY FUNNELS INTO THE GREAT LAKES FROM CANADA IN BEHIND THE SYSTEM. WITH THIS IDEA OF COOLING INTO THE WEEKEND...WILL GO OPPOSITE OF THE CLIMATOLOGY INDUCED RISE IN MEX GUIDANCE FROM FRIDAY INTO SATURDAY. AT BEST...WILL KEEP FRIDAY/SATURDAY VERY CLOSE TO THE SAME...WITH A FEW DEGREE RISE BY SUNDAY. && .DTX WATCHES/WARNINGS/ADVISORIES... .MI...NONE. .LAKE HURON... GALE WARNING...FOR THE SOUTH HALF...THROUGH SUNDAY MORNING. GALE WARNING...FOR THE NEARSHORE WATERS EXCLUSIVE OF INNER SAGINAW BAY...TONIGHT. SMALL CRAFT ADVISORY...INNER SAGINAW BAY...TONIGHT. .LAKE ST CLAIR...GALE WARNING...THROUGH SUNDAY MORNING. .MI WATERS OF LAKE ERIE...GALE WARNING...TONIGHT. && $$ DWD/BRAVENDER/DEG mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 655 PM EST SAT APR 2 2005 .AVIATION... BARRING ANY UNEXPECTED WESTWARD BULGING OF PRECIPITATION SHIELD FROM EASTERN SYSTEM...AM NO LONGER EXPECTING ANY MORE PRECIPITATION OR NON VFR CEILINGS OVER TAF SITES THIS EVENING...AND THIS IS ESPECIALLY SO THROUGH THE OVERNIGHT AND SUNDAY TIME FRAME AS DRY AIR AND SUBSIDENCE REIGN...NO RESTRICTION TO VISIBILITY EXPECTED EITHER. EXPECT SLOW DROPPING OFF OF THE WINDS TONIGHT...ESPECIALLY GUSTINESS...AS CLEARING SKIES PROMOTE DECOUPLING/STABILIZATION AND INHIBIT MIXING. STILL BEING AFFECTED SUNDAY IN FAIRLY BRISK CYCLONIC FLOW AROUND EASTERN SYSTEM...THOUGH...AND DIURNAL HEATING WILL AGAIN DEEPEN MIXING LAYER AND PROMOTE GUSTINESS BY AFTERNOON. && .UPDATE...ISSUED 555 PM EST SAT UPDATE TO WATCHES/WARNINGS/ADVISORIES SECTION BELOW. && .SHORT TERM...TONIGHT AND SUNDAY...ISSUED 355 PM EST SAT 12Z RAOBS/WATER VAPOR LOOP SHOW AN UPPER LOW MOVING THROUGH THE TENNESSEE/OHIO VALLEYS...WITH THE SURFACE LOW REDEVELOPING ALONG THE MID ATLANTIC COAST. REGIONAL RADARS SHOW PERSISTENT PRECIP BAND ACROSS SOUTHEASTERN ONTARIO...STILL BRUSHING THE FAR SOUTHEAST CWA. VIS SATELLITE SHOWS CLEARING UPSTREAM...WITH ONLY THINNING HIGH CLOUDS ACROSS THE SAGINAW VALLEY. MAIN FOCUS FOR THE FIRST 24 HOURS WILL BE WITH INITIAL PRECIP. 18Z RUC IS A BIT SLOWER THAN THE 12Z/15Z RUNS TAKING THE BEST MID-LEVEL DEFORMATION THROUGH THE CWA...AND CONSEQUENTLY HOLD ON TO LIFT ACROSS THE FAR SOUTHEAST CWA FOR LONGER. REGIONAL RADARS HAVE SHOWN A SLIGHT REORIENTATION WITH BETTER LIFT DEVELOPING FARTHER NORTH ACROSS ONTARIO AS THE VORT CENTER SWINGS BACK AROUND THE CUTOFF LOW. WILL HOLD ON TO CATEGORICAL POPS INTO THE EARLY EVENING ACROSS THE VERY FAR SOUTHEAST CWA...MAINLY MACOMB/ST CLAIR BASED ON RECENT RADAR TRENDS. AS FAR A PRECIP TYPE...RECENT TAMDAR SOUNDINGS CONTINUE TO SHOW FREEZING LEVELS GENERALLY 1.6-18.KFT ACROSS THE SOUTHEAST CWA. THERE HAVE BEEN MORE SNOW REPORTS...ESPECIALLY FROM THE PHN/YZR AREA...CORRESPONDING WITH STRONGER RADAR RETURNS/HEAVIER PRECIP RATES. WILL ALLOW FOR MORE SNOW ACROSS ST CLAIR COUNTY...AND KEEP IT JUST A CHANCE OF SNOW MIXED IN ACROSS MACOMB. 1000-850MB TRAJECTORIES SUPPORT A SLOWER CLEARING TREND...AT LEAST ACROSS THE EASTERN CWA. WITH CLOUD SHIELD ALREADY PRETTY THIN ACROSS THE NORTHWEST...SHOULD SEE CLEARING PRETTY EARLY IN THE TRI CITIES. ACTUALLY WILL START MIDLAND/BAY AS MOSTLY CLEAR. DEEPER MOISTURE WILL CONTINUE TO PULL EAST AS THE SYSTEM MOVE TO EASTERN PENNSYLVANIA TONIGHT AND FURTHER WRAPS UP...ALLOWING THE CLEARING SKIES TO WORK THROUGH THE CWA. GRADIENT STAYS PRETTY STRONG THROUGH SUNDAY...WITH A PRETTY WELL MIXED BOUNDARY LAYER THROUGH THE NIGHT LEADING TO SOME CONTINUED GUSTINESS. NOT MUCH OF A TEMPERATURE GRADIENT ACROSS THE STATE WITH LITTLE THERMAL ADVECTION BEHIND THIS SYSTEM...BUT WILL KEEP LOWS A COUPLE DEGREES COLDER ACROSS THE SAGINAW VALLEY WITH EARLIER CLEARING. THERE SHOULD BE A GOOD DEAL OF SUNSHINE ON SUNDAY. HOWEVER...BOTH NAM/GFS TRY TO BRING IN THE MID-LEVEL DECK FROM MINNESOTA. UPPER FLOW BECOMES MORE CONFLUENT ACROSS THE STATE BETWEEN SHORTWAVE RIDGE OVER THE WESTERN GREAT LAKES AND LOW OVER THE NORTHEAST. THIS MID/UPPER LEVEL MOISTURE MAY HAVE A DIFFICULT TIME MAKING IT THIS FAR EAST...BUT THERE SHOULD BE ENOUGH CLOUDS AROUND FOR MOSTLY SUNNY AS OPPOSED TO PLAIN SUNNY SKIES. FORECAST SOUNDINGS SHOW US MIXING UP TO 850MB...WHERE TEMPERATURES HOVER FROM -2C TO 0C. WITH GOOD APRIL INSOLATION...THIS SHOULD HELP US CLIMB BACK INTO THE 50S. && .LONG TERM...MONDAY THROUGH SATURDAY...ISSUED 355 PM EST SAT INITIAL PROBLEMS IN THE LONG TERM WILL BE JUST HOW MILD TO GO WITH TEMPERATURES AS CURRENT SYSTEM WORKS SLOWLY OFF TO THE NORTHEAST & WEST/NORTHWEST FLOW SETS IN BEHIND IT. THEREAFTER...SOUTHERLY FLOW GRADUALLY SETS UP AS NEXT WEATHER MAKER DIGS INTO THE OHIO VALLEY BY WEDNESDAY AND THURSDAY. MODELS ALL SHOW A VERY VIGOROUS UPPER LOW DEVELOPING IN THE AREA BY MID/LATE WEEK...BUT DIFFER RATHER SIGNIFICANTLY WITH EACH OTHER AND FROM RUN TO RUN. TREND...HOWEVER...SUGGESTS THAT AN EXTENDED PERIOD OF RAIN IS ON TAP DURING THE EXTENDED FORECAST...OR AT THE VERY LEAST...A 2 OR 3 DAY PERIOD IN WHICH VARIOUS "WAVES" OF RAIN AND EMBEDDED THUNDER...WILL ROTATE THROUGH THE AREA. IN TERMS OF TEMPERATURES...WILL MAKE SOME ADJUSTMENTS TO LAKESHORE TEMPERATURES ON DAYS IN WHICH AN ONSHORE FLOW SEEMS MORE LIKELY. NAMELY ON MONDAY AS LIGHT...NORTHWEST FLOW SHOULD BE DOMINATED BY LAKE BREEZE BY AFTERNOON. THEN...AS AFOREMENTIONED SYSTEM WRAPS UP TO OUR SOUTHWEST...OVERALL SYNOPTIC FLOW WILL TEND TO A SOLID SOUTHEASTERLY DIRECTION. HENCE...WARMEST IN THE WEST CENTRAL CWA AND COLDEST OFF LAKE ERIE/LAKE HURON. TREND WILL BE FOR MILD WEATHER INTO THE WEDNESDAY AND PERHAPS THURSDAY TIMEFRAME...DEPENDING ON JUST HOW/WHERE THIS UPPER LOW PRESSURE SYSTEM EVOLVES. THEREAFTER...EXPECT A COOL DOWN FOR THE UPCOMING WEEKEND AS CORE OF SYSTEM (AND ASSOCIATED COLDER AIR) DRIFTS THROUGH OR VERY NEAR THE AREA...AND COLDER AIR EVENTUALLY FUNNELS INTO THE GREAT LAKES FROM CANADA IN BEHIND THE SYSTEM. WITH THIS IDEA OF COOLING INTO THE WEEKEND...WILL GO OPPOSITE OF THE CLIMATOLOGY INDUCED RISE IN MEX GUIDANCE FROM FRIDAY INTO SATURDAY. AT BEST...WILL KEEP FRIDAY/SATURDAY VERY CLOSE TO THE SAME...WITH A FEW DEGREE RISE BY SUNDAY. && .DTX WATCHES/WARNINGS/ADVISORIES... .MI...NONE. .LAKE HURON... GALE WARNING...FOR THE SOUTH HALF...THROUGH SUNDAY MORNING. GALE WARNING...FOR THE NEARSHORE WATERS EXCLUSIVE OF INNER SAGINAW BAY...TONIGHT. SMALL CRAFT ADVISORY...INNER SAGINAW BAY...TONIGHT. .LAKE ST CLAIR...GALE WARNING...THROUGH SUNDAY MORNING. .MI WATERS OF LAKE ERIE...GALE WARNING...TONIGHT. && $$ DWD/BRAVENDER/DEG mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 555 PM EST SAT APR 2 2005 .UPDATE... UPDATE TO WATCHES/WARNINGS/ADVISORIES SECTION BELOW. && .SHORT TERM...TONIGHT AND SUNDAY...ISSUED 355 PM EST SAT 12Z RAOBS/WATER VAPOR LOOP SHOW AN UPPER LOW MOVING THROUGH THE TENNESSEE/OHIO VALLEYS...WITH THE SURFACE LOW REDEVELOPING ALONG THE MID ATLANTIC COAST. REGIONAL RADARS SHOW PERSISTENT PRECIP BAND ACROSS SOUTHEASTERN ONTARIO...STILL BRUSHING THE FAR SOUTHEAST CWA. VIS SATELLITE SHOWS CLEARING UPSTREAM...WITH ONLY THINNING HIGH CLOUDS ACROSS THE SAGINAW VALLEY. MAIN FOCUS FOR THE FIRST 24 HOURS WILL BE WITH INITIAL PRECIP. 18Z RUC IS A BIT SLOWER THAN THE 12Z/15Z RUNS TAKING THE BEST MID-LEVEL DEFORMATION THROUGH THE CWA...AND CONSEQUENTLY HOLD ON TO LIFT ACROSS THE FAR SOUTHEAST CWA FOR LONGER. REGIONAL RADARS HAVE SHOWN A SLIGHT REORIENTATION WITH BETTER LIFT DEVELOPING FARTHER NORTH ACROSS ONTARIO AS THE VORT CENTER SWINGS BACK AROUND THE CUTOFF LOW. WILL HOLD ON TO CATEGORICAL POPS INTO THE EARLY EVENING ACROSS THE VERY FAR SOUTHEAST CWA...MAINLY MACOMB/ST CLAIR BASED ON RECENT RADAR TRENDS. AS FAR A PRECIP TYPE...RECENT TAMDAR SOUNDINGS CONTINUE TO SHOW FREEZING LEVELS GENERALLY 1.6-18.KFT ACROSS THE SOUTHEAST CWA. THERE HAVE BEEN MORE SNOW REPORTS...ESPECIALLY FROM THE PHN/YZR AREA...CORRESPONDING WITH STRONGER RADAR RETURNS/HEAVIER PRECIP RATES. WILL ALLOW FOR MORE SNOW ACROSS ST CLAIR COUNTY...AND KEEP IT JUST A CHANCE OF SNOW MIXED IN ACROSS MACOMB. 1000-850MB TRAJECTORIES SUPPORT A SLOWER CLEARING TREND...AT LEAST ACROSS THE EASTERN CWA. WITH CLOUD SHIELD ALREADY PRETTY THIN ACROSS THE NORTHWEST...SHOULD SEE CLEARING PRETTY EARLY IN THE TRI CITIES. ACTUALLY WILL START MIDLAND/BAY AS MOSTLY CLEAR. DEEPER MOISTURE WILL CONTINUE TO PULL EAST AS THE SYSTEM MOVE TO EASTERN PENNSYLVANIA TONIGHT AND FURTHER WRAPS UP...ALLOWING THE CLEARING SKIES TO WORK THROUGH THE CWA. GRADIENT STAYS PRETTY STRONG THROUGH SUNDAY...WITH A PRETTY WELL MIXED BOUNDARY LAYER THROUGH THE NIGHT LEADING TO SOME CONTINUED GUSTINESS. NOT MUCH OF A TEMPERATURE GRADIENT ACROSS THE STATE WITH LITTLE THERMAL ADVECTION BEHIND THIS SYSTEM...BUT WILL KEEP LOWS A COUPLE DEGREES COLDER ACROSS THE SAGINAW VALLEY WITH EARLIER CLEARING. THERE SHOULD BE A GOOD DEAL OF SUNSHINE ON SUNDAY. HOWEVER...BOTH NAM/GFS TRY TO BRING IN THE MID-LEVEL DECK FROM MINNESOTA. UPPER FLOW BECOMES MORE CONFLUENT ACROSS THE STATE BETWEEN SHORTWAVE RIDGE OVER THE WESTERN GREAT LAKES AND LOW OVER THE NORTHEAST. THIS MID/UPPER LEVEL MOISTURE MAY HAVE A DIFFICULT TIME MAKING IT THIS FAR EAST...BUT THERE SHOULD BE ENOUGH CLOUDS AROUND FOR MOSTLY SUNNY AS OPPOSED TO PLAIN SUNNY SKIES. FORECAST SOUNDINGS SHOW US MIXING UP TO 850MB...WHERE TEMPERATURES HOVER FROM -2C TO 0C. WITH GOOD APRIL INSOLATION...THIS SHOULD HELP US CLIMB BACK INTO THE 50S. && .LONG TERM...MONDAY THROUGH SATURDAY...ISSUED 355 PM EST SAT INITIAL PROBLEMS IN THE LONG TERM WILL BE JUST HOW MILD TO GO WITH TEMPERATURES AS CURRENT SYSTEM WORKS SLOWLY OFF TO THE NORTHEAST & WEST/NORTHWEST FLOW SETS IN BEHIND IT. THEREAFTER...SOUTHERLY FLOW GRADUALLY SETS UP AS NEXT WEATHER MAKER DIGS INTO THE OHIO VALLEY BY WEDNESDAY AND THURSDAY. MODELS ALL SHOW A VERY VIGOROUS UPPER LOW DEVELOPING IN THE AREA BY MID/LATE WEEK...BUT DIFFER RATHER SIGNIFICANTLY WITH EACH OTHER AND FROM RUN TO RUN. TREND...HOWEVER...SUGGESTS THAT AN EXTENDED PERIOD OF RAIN IS ON TAP DURING THE EXTENDED FORECAST...OR AT THE VERY LEAST...A 2 OR 3 DAY PERIOD IN WHICH VARIOUS "WAVES" OF RAIN AND EMBEDDED THUNDER...WILL ROTATE THROUGH THE AREA. IN TERMS OF TEMPERATURES...WILL MAKE SOME ADJUSTMENTS TO LAKESHORE TEMPERATURES ON DAYS IN WHICH AN ONSHORE FLOW SEEMS MORE LIKELY. NAMELY ON MONDAY AS LIGHT...NORTHWEST FLOW SHOULD BE DOMINATED BY LAKE BREEZE BY AFTERNOON. THEN...AS AFOREMENTIONED SYSTEM WRAPS UP TO OUR SOUTHWEST...OVERALL SYNOPTIC FLOW WILL TEND TO A SOLID SOUTHEASTERLY DIRECTION. HENCE...WARMEST IN THE WEST CENTRAL CWA AND COLDEST OFF LAKE ERIE/LAKE HURON. TREND WILL BE FOR MILD WEATHER INTO THE WEDNESDAY AND PERHAPS THURSDAY TIMEFRAME...DEPENDING ON JUST HOW/WHERE THIS UPPER LOW PRESSURE SYSTEM EVOLVES. THEREAFTER...EXPECT A COOL DOWN FOR THE UPCOMING WEEKEND AS CORE OF SYSTEM (AND ASSOCIATED COLDER AIR) DRIFTS THROUGH OR VERY NEAR THE AREA...AND COLDER AIR EVENTUALLY FUNNELS INTO THE GREAT LAKES FROM CANADA IN BEHIND THE SYSTEM. WITH THIS IDEA OF COOLING INTO THE WEEKEND...WILL GO OPPOSITE OF THE CLIMATOLOGY INDUCED RISE IN MEX GUIDANCE FROM FRIDAY INTO SATURDAY. AT BEST...WILL KEEP FRIDAY/SATURDAY VERY CLOSE TO THE SAME...WITH A FEW DEGREE RISE BY SUNDAY. && .AVIATION...ISSUED 1255 PM EST SAT DTX RADAR SHOWS LIGHT PRECIP CONTINUING ACROSS FAR SOUTHEAST MICHIGAN...AFFECTING DTW/DET WITH MVFR CIGS/VFR VIS. SOME SCALE CONTRACTION APPARENT ON RADAR VICINITY OF THE ST CLAIR RIVER...WITH YZR/SARNIA DOWN TO 3/4SM IN SNOW FOR A BRIEF PERIOD AROUND 17Z. PHN ALSO REPORTED MVFR/SNOW FOR A WHILE...BUT IS NOW BACK TO VFR/RAIN. WILL KEEP A PREDOMINATE LIGHT RAIN WITH NO VIS RESTRICTION AT DTW/DET...BUT ALSO MENTION A FEW HOUR TEMPO OF MIXED RAIN/SNOW AT DET GIVEN ITS PROXIMITY TO THIS MORE CONCENTRATED BAND. OTHERWISE THE REMAINING QUESTION IS WITH CLOUDS AND WINDS. 1000-850MB STREAMLINES SHOW WINDS REMAINING OUT OF THE NORTH/NORTHEAST THROUGH 00Z ACROSS MUCH OF SOUTHEAST MICHIGAN...WHICH WILL KEEP THE LOW CLOUD DECK ACROSS THE AREA FOR LONGER. WILL KEEP MVFR CIGS AT FNT FOR AT LEAST A FEW MORE HOURS...FINALLY SCATTERED THEM OUT TOWARD 00Z ONCE WINDS BACK MORE NORTHWEST. SIMILAR STORY AT DTW/DET...JUST DELAYED UNTIL LATE EVENING. WINDS WILL DIMINISH A BIT THIS EVENING...BUT FORECAST SOUNDINGS SHOW THE BOUNDARY LAYER REMAINING WELL MIXED /ESPECIALLY ACROSS THE SOUTHEAST/...SO WILL KEEP RATHER GUSTY WINDS GOING THROUGH THE OVERNIGHT. THIS WILL ALSO LIMITED THE NON-CONVECTIVE LOW-LEVEL WIND SHEAR POTENTIAL WITH THE STRONG LOW-LEVEL JET. DTX VWP AND TAMDAR PROFILES SHOW A SOLID 60KT JET ACROSS SOUTHEAST MICHIGAN...AND WHILE THE 12Z NAM/15Z RUC SHIFT THIS JET TO THE EAST...BOTH STILL SHOW 50KTS AT 850MB THROUGH MUCH OF THE NIGHT. && .DTX WATCHES/WARNINGS/ADVISORIES... .MI...NONE. .LAKE HURON... GALE WARNING...FOR THE SOUTH HALF...THROUGH SUNDAY MORNING. GALE WARNING...FOR THE NEARSHORE WATERS EXCLUSIVE OF INNER SAGINAW BAY...TONIGHT. SMALL CRAFT ADVISORY...INNER SAGINAW BAY...TONIGHT. .LAKE ST CLAIR...GALE WARNING...THROUGH SUNDAY MORNING. .MI WATERS OF LAKE ERIE...GALE WARNING...TONIGHT. && $$ DWD/BRAVENDER/DEG mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 355 PM EST SAT APR 2 2005 .SHORT TERM...TONIGHT AND SUNDAY 12Z RAOBS/WATER VAPOR LOOP SHOW AN UPPER LOW MOVING THROUGH THE TENNESSEE/OHIO VALLEYS...WITH THE SURFACE LOW REDEVELOPING ALONG THE MID ATLANTIC COAST. REGIONAL RADARS SHOW PERSISTENT PRECIP BAND ACROSS SOUTHEASTERN ONTARIO...STILL BRUSHING THE FAR SOUTHEAST CWA. VIS SATELLITE SHOWS CLEARING UPSTREAM...WITH ONLY THINNING HIGH CLOUDS ACROSS THE SAGINAW VALLEY. MAIN FOCUS FOR THE FIRST 24 HOURS WILL BE WITH INITIAL PRECIP. 18Z RUC IS A BIT SLOWER THAN THE 12Z/15Z RUNS TAKING THE BEST MID-LEVEL DEFORMATION THROUGH THE CWA...AND CONSEQUENTLY HOLD ON TO LIFT ACROSS THE FAR SOUTHEAST CWA FOR LONGER. REGIONAL RADARS HAVE SHOWN A SLIGHT REORIENTATION WITH BETTER LIFT DEVELOPING FARTHER NORTH ACROSS ONTARIO AS THE VORT CENTER SWINGS BACK AROUND THE CUTOFF LOW. WILL HOLD ON TO CATEGORICAL POPS INTO THE EARLY EVENING ACROSS THE VERY FAR SOUTHEAST CWA...MAINLY MACOMB/ST CLAIR BASED ON RECENT RADAR TRENDS. AS FAR A PRECIP TYPE...RECENT TAMDAR SOUNDINGS CONTINUE TO SHOW FREEZING LEVELS GENERALLY 1.6-18.KFT ACROSS THE SOUTHEAST CWA. THERE HAVE BEEN MORE SNOW REPORTS...ESPECIALLY FROM THE PHN/YZR AREA...CORRESPONDING WITH STRONGER RADAR RETURNS/HEAVIER PRECIP RATES. WILL ALLOW FOR MORE SNOW ACROSS ST CLAIR COUNTY...AND KEEP IT JUST A CHANCE OF SNOW MIXED IN ACROSS MACOMB. 1000-850MB TRAJECTORIES SUPPORT A SLOWER CLEARING TREND...AT LEAST ACROSS THE EASTERN CWA. WITH CLOUD SHIELD ALREADY PRETTY THIN ACROSS THE NORTHWEST...SHOULD SEE CLEARING PRETTY EARLY IN THE TRI CITIES. ACTUALLY WILL START MIDLAND/BAY AS MOSTLY CLEAR. DEEPER MOISTURE WILL CONTINUE TO PULL EAST AS THE SYSTEM MOVE TO EASTERN PENNSYLVANIA TONIGHT AND FURTHER WRAPS UP...ALLOWING THE CLEARING SKIES TO WORK THROUGH THE CWA. GRADIENT STAYS PRETTY STRONG THROUGH SUNDAY...WITH A PRETTY WELL MIXED BOUNDARY LAYER THROUGH THE NIGHT LEADING TO SOME CONTINUED GUSTINESS. NOT MUCH OF A TEMPERATURE GRADIENT ACROSS THE STATE WITH LITTLE THERMAL ADVECTION BEHIND THIS SYSTEM...BUT WILL KEEP LOWS A COUPLE DEGREES COLDER ACROSS THE SAGINAW VALLEY WITH EARLIER CLEARING. THERE SHOULD BE A GOOD DEAL OF SUNSHINE ON SUNDAY. HOWEVER...BOTH NAM/GFS TRY TO BRING IN THE MID-LEVEL DECK FROM MINNESOTA. UPPER FLOW BECOMES MORE CONFLUENT ACROSS THE STATE BETWEEN SHORTWAVE RIDGE OVER THE WESTERN GREAT LAKES AND LOW OVER THE NORTHEAST. THIS MID/UPPER LEVEL MOISTURE MAY HAVE A DIFFICULT TIME MAKING IT THIS FAR EAST...BUT THERE SHOULD BE ENOUGH CLOUDS AROUND FOR MOSTLY SUNNY AS OPPOSED TO PLAIN SUNNY SKIES. FORECAST SOUNDINGS SHOW US MIXING UP TO 850MB...WHERE TEMPERATURES HOVER FROM -2C TO 0C. WITH GOOD APRIL INSOLATION...THIS SHOULD HELP US CLIMB BACK INTO THE 50S. .LONG TERM...MONDAY THROUGH SATURDAY INITIAL PROBLEMS IN THE LONG TERM WILL BE JUST HOW MILD TO GO WITH TEMPERATURES AS CURRENT SYSTEM WORKS SLOWLY OFF TO THE NORTHEAST & WEST/NORTHWEST FLOW SETS IN BEHIND IT. THEREAFTER...SOUTHERLY FLOW GRADUALLY SETS UP AS NEXT WEATHER MAKER DIGS INTO THE OHIO VALLEY BY WEDNESDAY AND THURSDAY. MODELS ALL SHOW A VERY VIGOROUS UPPER LOW DEVELOPING IN THE AREA BY MID/LATE WEEK...BUT DIFFER RATHER SIGNIFICANTLY WITH EACH OTHER AND FROM RUN TO RUN. TREND...HOWEVER...SUGGESTS THAT AN EXTENDED PERIOD OF RAIN IS ON TAP DURING THE EXTENDED FORECAST...OR AT THE VERY LEAST...A 2 OR 3 DAY PERIOD IN WHICH VARIOUS "WAVES" OF RAIN AND EMBEDDED THUNDER...WILL ROTATE THROUGH THE AREA. IN TERMS OF TEMPERATURES...WILL MAKE SOME ADJUSTMENTS TO LAKESHORE TEMPERATURES ON DAYS IN WHICH AN ONSHORE FLOW SEEMS MORE LIKELY. NAMELY ON MONDAY AS LIGHT...NORTHWEST FLOW SHOULD BE DOMINATED BY LAKE BREEZE BY AFTERNOON. THEN...AS AFOREMENTIONED SYSTEM WRAPS UP TO OUR SOUTHWEST...OVERALL SYNOPTIC FLOW WILL TEND TO A SOLID SOUTHEASTERLY DIRECTION. HENCE...WARMEST IN THE WEST CENTRAL CWA AND COLDEST OFF LAKE ERIE/LAKE HURON. TREND WILL BE FOR MILD WEATHER INTO THE WEDNESDAY AND PERHAPS THURSDAY TIMEFRAME...DEPENDING ON JUST HOW/WHERE THIS UPPER LOW PRESSURE SYSTEM EVOLVES. THEREAFTER...EXPECT A COOL DOWN FOR THE UPCOMING WEEKEND AS CORE OF SYSTEM (AND ASSOCIATED COLDER AIR) DRIFTS THROUGH OR VERY NEAR THE AREA...AND COLDER AIR EVENTUALLY FUNNELS INTO THE GREAT LAKES FROM CANADA IN BEHIND THE SYSTEM. WITH THIS IDEA OF COOLING INTO THE WEEKEND...WILL GO OPPOSITE OF THE CLIMATOLOGY INDUCED RISE IN MEX GUIDANCE FROM FRIDAY INTO SATURDAY. AT BEST...WILL KEEP FRIDAY/SATURDAY VERY CLOSE TO THE SAME...WITH A FEW DEGREE RISE BY SUNDAY. && .DTX WATCHES/WARNINGS/ADVISORIES... .MI...NONE. .LAKE HURON... GALE WARNING...FOR THE SOUTH HALF...THROUGH SUNDAY MORNING. GALE WARNING...FOR THE NEARSHORE WATERS...TONIGHT .LAKE ST CLAIR...GALE WARNING...THROUGH SUNDAY MORNING. .MI WATERS OF LAKE ERIE...GALE WARNING...TONIGHT && $$ BRAVENDER/DEG mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 330 PM EST SAT APR 2 2005 .DISCUSSION... 12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW HI AMPLITUDE BUT SHORT WAVELENGTH UPR TROF OVER THE ERN CONUS BTWN RDG OVER THE PLAINS AND IN THE WRN ATLANTIC. DEEPENING SFC LO OVER THE CENTRAL APPALACHIANS UNDER THE CUTOFF H5 LO IN THE OH VALLEY THAT IS EMBEDDED WITHIN THE UPR TROF. FA DOMINATED BY DRY NNE FLOW BTWN THE SFC LO AND SFC RDG AXIS STRETCHING FM NW ONTARIO ACRS WRN LK SUP AND INTO THE CENTRAL PLAINS. 12Z MPX/INL SDNGS ARE BONE DRY BLO SOME UPR MSTR ABV H5. SERIES OF SHRTWVS OVER SCNTRL CAN ARE CRASHING ACRS THE TOP OF THE PLAINS RDG. LEADING EDGE OF COMMA TAIL MID/HI CLD STRETCHING S FM LEAD SHRTWV/SFC LO NW OF LK WINNIPEG IS NOW MOVING THRU MN AND APRCHG WRN LK SUP WELL IN ADVANCE OF ATTENDANT SFC TROF IN THE NRN PLAINS. BUT NO PCPN OR EVEN LOWER CLD NOTED AS 12Z BIS SDNG IS VERY DRY BLO HIER MSTR ABV H6 DESPITE 12HR H5 HGT FALLS ARND 100M. MORE SHRTWVS APRCHG THE PAC NW COAST. MAIN FCST CONCERNS INTO TUE ARE TEMPS. FOCUS THEN SHIFTS TO TIMING/ IMPACT OF SHRTVS NOW APRCHG THE PAC NW COAST. FOR TNGT...UPR RDG HELD IN PLACE BY DEEPENING DOWNSTREAM LO OVER THE APPALACHIANS FCST TO BE BATTERED DOWN A BIT BY SCNTRL CNDN SHRTWV THAT MOVES INTO HUDSON BAY BY 12Z. SFC TROF FCST TO REACH THE WRN ZNS TOWARD 12Z. BAND OF DPVA/HIER MID-HI LVL RH IN ADVANCE OF THE FCST TO MOVE INTO THE FA THIS EVNG...BUT THEN LIFT MORE TO THE N INTO ONTARIO AS DOWNSTREAM BLOCK HOLDS FIRM AND MAINTAINS DRY AIRMASS IN PLACE OVER THE UPR GRT LKS. EXPECT LOWEST MIN TEMPS BLO MOS GUIDANCE OVER THE INTERIOR ECNTRL CWA WHERE SGNFT HIER LVL RH AND AC/CI WL HAVE A HARDER TIME REACHING AND SFC RDG AXIS/LIGHTER WINDS HOLD IN PLACE. SINCE FOG FORMED THIS MRNG UNDER THE RDG AXIS...CONSIDERED ADDED PTCHY FOG TNGT OVER THESE COLDER INTERIOR ECNTRL PLACES. BUT AIRMASS APPEARS TOO DRY THIS AFTN...SO LEFT IT OUT. QUIET DAY ON TAP FOR SUN AS BLDG HI PRES IN NW ONTARIO IN THE WAKE OF SHRTWV LIFTING NEWD THRU HUDSON BAY MERGES WITH RDG IN PLACE OVER THE UPR LKS W OF DEEPENING NE LO. ALTHOUGH LLVL FLOW SHIFTS MORE NNW LATER IN THE DAY IN RESPONSE TO RISING MSLP IN NW ONTARIO...LLVL FLOW WLY ENUF IN THE MRNG WHEN THERMAL RDG ASSOCIATED WITH WEAKENING SFC TROF OVHD WL MEAN MINIMAL LK MODERATION FOR MUCH OF THE DAY (EXCEPT OVER THE W) AND A MUCH WARMER AFTN THAN TDAY. MIXING TO H75-8 ON PREFERRED GFS FCST SDNGS YIELDS TMAX APRCHG 57 OVER INTERIOR LOCATIONS. THE INTENSE SFC HTG AND TREND FOR HIER PRES TO THE NW SHOULD DVLP A HEALTHY LK BREEZE LATER IN THE AFTN OFF OF LK SUP. GFS LLVL MSTR DOES APPEAR TO BE TOO GENEROUS...PREFER DRIER ETA SOLN THAT SUPPORTS ONLY SCT DIURNAL CU AFTER LINGERING AC DRIES OUT IN THE MRNG. DRY HI PRES RDG FCST TO BLD INTO THE UPR GRT LKS SUN NGT/MON... BRINGING MORE TRANQUIL WX. ALTHOUGH PWAT FCST TO FALL BLO 0.25 INCH SUN NGT...NLY H925 WIND MAY MAINTAIN ENUF MIXING TO PREVENT TEMP FM FALLING TO DWPT. WL STILL GO BLO MOS GUIDANCE FOR INTERIOR LOCATIONS OVER THE WCNTRL ZNS SHELTERED FM NNE WIND AND WHERE PRES GRADIENT FCST TO BE A BIT MORE SLACK. AS HI PRES RDG AXIS SHIFTS JUST E OF THE FA ON MON...LLVL FLOW IS FCST TO BECOME MORE ESE...INCRSG LK MODERATION DOWNWIND OF LK MI AND FM MQT-KEWEENAW. H85 TEMPS FCST TO REACH ARND 6C AT IWD BY LATE IN THE DAY...WHERE DOWNSLOPING ESE FLOW WL ACCENTUATE WRMG. EXPECT SOME HI CLD TO DRIFT OVER UPR RDG AXIS INTO THE WRN FA IN THE AFTN...OTRW DRY LLVLS SHOULD INHIBIT FORMATION OF MUCH MORE THAN A FEW CU. MIXING TO JUST H85 YIELDS TMAX APRCHG 65 AT IWD WELL ABV MOS GUIDANCE...RSNBL CONSIDERING DOWNSLOPING FLOW. TEMPS GENERALLY AOA MOS GUIDANCE...WHICH HAS BEEN RUNNING TOO LO RECENTLY ESPECIALLY IN DRIER AIRMASSES. RETURN SLY FLOW/ISENTROPIC LIFT BTWN SLOWLY RETREATING HI PRES RDG/FALLING PRES IN THE PLAINS ASSOCIATED WITH DEEPENING WRN TROF BEGINS TO SET UP MON NGT. GFS EVEN GENERATES SOME PCPN OVER THE W HALF OF FA AS H85 WARM FNT APRCHS TOWARD 12Z TUE AND H85-5 LAPSE RATES INCRS TO ARND 7.5C/KM (H85 TEMP FCST NR 11C AT IWD). BUT H85 DWPT FCST ONLY TO ARND 5-6C...AND EVEN MOISTER GFS SHOWS A DRY LYR LINGERING BLO HIER MID LVL MSTR SO THAT THERE WOULD LTL IF ANY POSITIVE AREA ON THE SDNG EVEN WITH ENVIRONMENTAL LAPSE RATE GREATER THAN MOIST ADIABATIC. CONSIDERING GFS WET BIAS AND DRY ANTECEDENT AIRMASS...WL HOLD OFF ON MENTIONING ANY PCPN ATTM...JUST SOME INCRSG MID/HI LVL CLD. THICKENING MID/HI CLD AND STEADY SE WIND WL PREVENT A SGNFT DIURNAL TEMP DROP...ESPECIALLY AT IWD-ONTONAGON. QUITE A BIT OF MODEL UNCERTAINTY IN REGARDS TO STORM SYS THAT MAY IMPACT UPR GRT LKS IN THE MID WEEK...ESPECIALLY THE DETAILS OF THE INTERACTION BTWN THE NRN AND SRN BRANCHES. ECMWF HAS BEEN VERY INCONSISTENT ON HANDLING THIS INTERACTION...AND THE 00Z RUN TRENDED TOWARD MORE EMPHASIS ON A SINGLE SRN STORM THAT WOULD ACTUALLY BE TOO FAR S FOR MUCH PCPN IN THE CWA. 00Z UKMET/GFS/CNDN ON THE OTHER HAND SHOW SEPARATE NRN BRANCH SHRTWV PUSHING A COLD FNT ACRS THE FA ON WED...THEN PHASING WITH THE SRN BRANCH TO DVLP A DEEP LO NOT FAR TO THE SE THAT WOULD ENVELOP FA IN DEEP CYC FLOW. 12Z GUIDANCE HAS CONTINUED TREND TOWARD A BIT SLOWER ARRIVAL OF PCPN ON TUE WITH DRY SE TRAJECTORIES OUT OF HI TO THE E HELD IN PLACE BY DOWNSTREAM BLOCKING LO...BUT ALSO WITH THE RANGE OF PSBL INTERACTIONS BTWN THE BRANCHES. 00Z CNDN/GFS ENSEMBLE FCSTS HINT THAT ALL THESE SOLNS ARE ENSEMBLE MEMBERS AND PSBL OUTCOMES. ONE NOTE OF AGREEMENT...MODELS HAVE TRENDED SLOWER WITH EWD PROGRESSION OF THIS SYS...WHICH MAKE SENSE CONSIDERING BLOCKING PATTERN THAT WL BE DVLPG OVER THE ATLANTIC OCEAN. HAVE OPTED TO FOLLOW CLOSE TO NCEP MANUAL GUIDANCE...WHICH PICKS UP ON THE SLOWER MODEL TREND AND PHASING OF BRANCHES. FCST WL BE DRY ON TUE EXCEPT FOR LO CHC POPS LATE IN THE DAY NR THE WI BORDER...CHC POPS FOR RA ON WED/EARLY THU...THEN A CHC OF RASN LATE THU/ FRI AS CYC FLOW DRAWS COLDER AIR INTO THE UPR GRT LKS. THEN FINALLY DRY ON SAT WITH BLDG HI PRES IN SCNTRL CAN. COORDINATED WITH GRB/APX/DLH. && .MQT...WATCHES/WARNINGS/ADVISORIES...NONE. && $$ KC mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 1255 PM EST SAT APR 2 2005 .AVIATION... DTX RADAR SHOWS LIGHT PRECIP CONTINUING ACROSS FAR SOUTHEAST MICHIGAN...AFFECTING DTW/DET WITH MVFR CIGS/VFR VIS. SOME SCALE CONTRACTION APPARENT ON RADAR VICINITY OF THE ST CLAIR RIVER...WITH YZR/SARNIA DOWN TO 3/4SM IN SNOW FOR A BRIEF PERIOD AROUND 17Z. PHN ALSO REPORTED MVFR/SNOW FOR A WHILE...BUT IS NOW BACK TO VFR/RAIN. WILL KEEP A PREDOMINATE LIGHT RAIN WITH NO VIS RESTRICTION AT DTW/DET...BUT ALSO MENTION A FEW HOUR TEMPO OF MIXED RAIN/SNOW AT DET GIVEN ITS PROXIMITY TO THIS MORE CONCENTRATED BAND. OTHERWISE THE REMAINING QUESTION IS WITH CLOUDS AND WINDS. 1000-850MB STREAMLINES SHOW WINDS REMAINING OUT OF THE NORTH/NORTHEAST THROUGH 00Z ACROSS MUCH OF SOUTHEAST MICHIGAN...WHICH WILL KEEP THE LOW CLOUD DECK ACROSS THE AREA FOR LONGER. WILL KEEP MVFR CIGS AT FNT FOR AT LEAST A FEW MORE HOURS...FINALLY SCATTERED THEM OUT TOWARD 00Z ONCE WINDS BACK MORE NORTHWEST. SIMILAR STORY AT DTW/DET...JUST DELAYED UNTIL LATE EVENING. WINDS WILL DIMINISH A BIT THIS EVENING...BUT FORECAST SOUNDINGS SHOW THE BOUNDARY LAYER REMAINING WELL MIXED /ESPECIALLY ACROSS THE SOUTHEAST/...SO WILL KEEP RATHER GUSTY WINDS GOING THROUGH THE OVERNIGHT. THIS WILL ALSO LIMITED THE NON-CONVECTIVE LOW-LEVEL WIND SHEAR POTENTIAL WITH THE STRONG LOW-LEVEL JET. DTX VWP AND TAMDAR PROFILES SHOW A SOLID 60KT JET ACROSS SOUTHEAST MICHIGAN...AND WHILE THE 12Z NAM/15Z RUC SHIFT THIS JET TO THE EAST...BOTH STILL SHOW 50KTS AT 850MB THROUGH MUCH OF THE NIGHT. && .UPDATE...1030 AM EST SAT APR 2 2005 REGIONAL RADARS/METARS SHOW PRECIP CONTINUING ACROSS THE SOUTHEAST CWA...IN AN AREA OF PERSISTENT MID-LEVEL DEFORMATION INDICATED BY THE 12Z RUC. THIS AREA OF LIFT SHOULD CONTINUE ACROSS SOUTHEAST MICHIGAN THROUGH 18Z...BEFORE SHIFTING DOWNSTREAM AS THE UPPER LOW BEGINS TO PULL EAST FASTER AS THE TWO VORT CENTERS MERGE AND HELP TO PULL IT ALONG. OBSERVATIONS HAVE SHOWN PRECIP TO BE MAINLY RAIN... WITH ONLY A FEW REPORTS OF UP OR RASN. 12Z DTX RAOB SHOWS FREEZING LEVEL/WET-BULB ZERO HEIGHTS AROUND 1.1KFT AGL. TAMDAR SOUNDINGS FROM FLIGHT PATHS FARTHER SOUTH AND EAST OF THE OFFICE ARE A BIT HIGHER...GENERALLY 1.3-1.6KFT AGL. GIVEN THE STRONG GRADIENT/WELL MIXED BOUNDARY LAYER AND LIMITED THERMAL ADVECTION...THIS RELATIVELY THIN WARM LAYER HAS NOT ERODED THROUGH EVAPORATIVE COOLING OR MELTING. EXPECT WE WILL CONTINUE TO HOVER RIGHT AROUND THE RAIN/SNOW THRESHOLD WITH THE NOD GOING TOWARD RAIN...AND WILL MAINTAIN THE CURRENT IDEA OF RAIN POSSIBLY MIXED WITH SNOW. WILL UPDATE TO TRIM BACK THE WEATHER GRIDS BASED ON LATEST RADAR TRENDS...BUT ALSO MAINTAIN CATEGORICAL POPS ACROSS THE FAR SOUTHEAST FOR A BIT LONGER INTO THE AFTERNOON. SATELLITE/METARS SHOW PLENTY OF DRY AIR WORKING IN ACROSS THE NORTH AND WEST CWA...SO SHOULD BE ABLE TO KEEP A SHARP CUTOFF TO THE PRECIP. && .SHORT TERM...SATURDAY AND SATURDAY NIGHT...ISSUED AT 321 AM PRECIPITATION SHIELD AND COLDER CLOUD TOPS ON IR LOOP BEGINNING TO DRAW BACK TO THE WEST AS SURFACE LOW CONTINUES TO TRACK NORTHEAST INTO WEST VIRGINIA...AND THETA-E ADVECTION INCREASES ON THE NORTH SIDE OF THE LOW. ANTICIPATE PRECIPITATION TO STEADILY INCREASE OVER THE EASTERN HALF OF THE CWA THROUGH 15Z. NOT REAL IMPRESSED WITH DEFORMATION AXIS OVER THE WESTERN GREAT LAKES AS IR LOOP CONTINUES TO SHOW CLOUD TOP WARMING OVER THE WESTERN PORTION OF THE STATE. MODELS SHOW THIS FEATURE ROTATING SOUTHEAST INTO THE CWA BETWEEN 12-15Z AND 500 MB FGEN FIELD STRENGTHENING FOR A BRIEF TIME BETWEEN 12-15Z. LOOKS LIKE THE MODELS MAY BE TO AGGRESSIVE WITH DEFORMATION AXIS AND 500 MB FGEN THOUGH. FIRST SHORT TERM CONCERN WILL BE PRECIPITATION TYPE. MID LEVELS CONTINUE TO BE COLD ENOUGH FOR SNOW...HOWEVER IT SHOULD TAKE SEVERAL HOURS TO ERODE DEEP WARM LAYER BELOW 2500 FT. MODELS NOW SHOWING WET BULB TEMPERATURES ABOVE FREEZING FROM THE SURFACE THROUGH 2K FEET THROUGH 12Z...THEN SLOWLY ERODING BETWEEN 1K-2K FT THROUGH 18Z. SURFACE DEW POINTS HAVE ALSO CLIMBED INTO THE MID 30S ACROSS THE SOUTHEAST PORTION OF THE CWA IN AREA OF ONGOING PRECIPITATION...SO LATENT HEAT RELEASE MAY ALREADY BE HAVING AN IMPACT. THERE WILL BE A FIGHT BETWEEN THE LATENT HEAT RELEASE AND COOLING DUE TO MELTING...ESPECIALLY ACROSS THE FAR SOUTHEAST PORTION OF THE CWA IN REGION OF HEAVIER PRECIPITATION. THERMAL FIELD REMAINS HOMOGENEOUS THOUGH SO WILL NOT HAVE TO CONTEND WITH MUCH WARM AIR ADVECTION. A COMPLICATING FACTOR WILL BE INCREASING NORTHEAST FLOW OFF OF THE COOLER LAKES...WHICH WILL ALSO HINDER BOUNDARY LAYER WARMING. SO ALL THINGS CONSIDER...EVEN WITH A DEEP WARM LAYER TO BEGIN WITH...RAIN/SNOW MIX STILL LOOKS LIKE THE WAY TO GO AFTER 12Z...ESPECIALLY WITH THE HOMOGENEOUS THERMAL FIELD OVER THE CENTRAL GREAT LAKES. A THIS TIME WILL KEEP SNOW ACCUMULATIONS CONFINED TO LESS THAN AN INCH. THIS WILL HAVE TO BE WATCHED CAREFULLY ACROSS THE FAR SOUTHEAST PORTION OF THE CWA THOUGH. MODELS SHOWING A BRIEF PERIOD OF INCREASING 850-700 MB FGEN DRAWING NORTHWEST INTO THE FAR SOUTHEAST PORTION OF THE CWA BETWEEN 12-15Z...SO ANTICIPATE THIS WILL BE THE TIME FRAME FOR MOST SIGNIFICANT QPF AND POTENTIAL MIX WITH SNOW. UPPER JET DYNAMICS ALREADY WELL EAST OF THE CWA...AND MODELS SHOW SOME JET COUPLING ALONG THE EAST COAST THIS AFTERNOON AND RAPID DEEPENING OF SURFACE LOW. CURRENT OBSERVATIONS INDICATE THIS IS ALREADY HAPPENING...WITH LOW ALREADY DOWN TO 994 OVER SOUTHERN WEST VIRGINIA. AS A RESULT NORTHEAST WINDS WILL INCREASE RAPIDLY ACROSS THE CENTRAL GREAT LAKES SO WILL NEED GALE WARNINGS FROM SOUTHERN LAKE HURON SOUTHWARD BY 18Z. MODEL DIFFERENCE ARE MINOR IN THE FIRST 24 HOURS...WITH THE NAM AND RUC VERY SIMILAR OVER THE GREAT LAKES REGION...GFS APPEARS TO BE A LITTLE TO COLD WITH THE 850 MB THERMAL FIELD OVER WISCONSIN...SHOWING A LARGE AREA OF -5C...WITH COLDEST OBS ONLY -3C...NAM HAS DONE A MUCH BETTER JOB THERE...SO SHORT TERM FORECAST WILL LEAN MORE TOWARD A NAM SOLUTION. NAM QPF ALSO A LITTLE MORE ROBUST WITH QPF THROUGH 15Z...WHICH MATCHES UP BETTER WITH CURRENT 6 HOUR QPF TOTALS OVER THE FAR EASTERN PORTION OF THE CWA AND POINTS EAST. ALTHOUGH MODELS STRIP PRECIPITATION OUT OF THE CWA QUICKLY THIS EVENING...WILL CONTINUE WITH A MENTION OF CHANCE POPS EAST THROUGH 06Z...DUE TO UNCERTAINTY IN CYCLOGENESIS ALONG THE EAST COAST AND ASSOCIATED EASTWARD PROGRESSION OF LOW LEVEL CYCLONIC FLOW. && .LONG TERM...ISSUED AT 321 AM AS THE STORM SLOWLY PULLS AWAY...THERE WILL STILL BE PLENTY OF WIND ON SUNDAY. AREA WILL BE MIXING UP TO 2K TO 4K FEET...WHICH WILL HELP BRING DOWN WIND GUSTS UP TO 35 KTS. SUNSHINE WILL HELP GET THE MIXING GOING ON SUNDAY. ONLY SOME HI MOISTURE FROM THE DEPARTING SYSTEM ON SUNDAY TO GIVE THE EASTERN HALF OF THE CWA SOME CI. WITH THE STRONG NW WINDS...AND 80H TEMPS STILL AROUND 0C...WENT TOWARD THE COOLER NAM GUIDANCE NUMBERS...EVEN WITH PLENTY OF SUN. AFTER SUNDAY...DRY AIR IS IN PLACE RIGHT UNTIL TUESDAY...BESIDES SOME CI AHEAD OF THE NEXT SYSTEM ON MONDAY NIGHT. ENOUGH DRY AIR TO JUST GO WITH CLEAR AND SUNNY FORECAST SUNDAY NIGHT AND MONDAY. BY TUESDAY...MOISTURE POOLS ALONG THE WARM FRONT JUST SOUTH OF THE STATE SO EXPECT SOME PARTLY SUNNY CONDITIONS. JUST NOT ENOUGH FORCING TO GET ANYTHING OTHER THAN CLOUDS WITH THE WARM FRONT. THEN THE 00Z GFS IS SLOWER WITH THE NEXT SYSTEM...LEANING MUCH MORE TOWARD THE UKMET...ECMWF AND CANADIAN...WHICH IS WHAT WAS GOING IN THE FORECAST. SO NO REAL CHANGES FROM TUESDAY TO FRIDAY. DID TWEAK HIGH TEMPERATURES THOUGH...JUST A BIT WARMER AHEAD OF THE FRONT FOR TUESDAY AND WEDNESDAY...AND THEN A BIT COOLER BEHIND THE FRONT. && .DTX WATCHES/WARNINGS/ADVISORIES... .MI...NONE. .LAKE HURON...GALE WARNING...SOUTH HALF...THROUGH SUNDAY AFTERNOON. .LAKE ST CLAIR...GALE WARNING...THROUGH SUNDAY AFTERNOON. .MI WATERS OF LAKE ERIE...GALE WARNING...THROUGH SUNDAY AFTERNOON. && $$ BRAVENDER/GSS/RBP mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 1030 AM EST SAT APR 2 2005 .UPDATE... REGIONAL RADARS/METARS SHOW PRECIP CONTINUING ACROSS THE SOUTHEAST CWA...IN AN AREA OF PERSISTENT MID-LEVEL DEFORMATION INDICATED BY THE 12Z RUC. THIS AREA OF LIFT SHOULD CONTINUE ACROSS SOUTHEAST MICHIGAN THROUGH 18Z...BEFORE SHIFTING DOWNSTREAM AS THE UPPER LOW BEGINS TO PULL EAST FASTER AS THE TWO VORT CENTERS MERGE AND HELP TO PULL IT ALONG. OBSERVATIONS HAVE SHOWN PRECIP TO BE MAINLY RAIN... WITH ONLY A FEW REPORTS OF UP OR RASN. 12Z DTX RAOB SHOWS FREEZING LEVEL/WET-BULB ZERO HEIGHTS AROUND 1.1KFT AGL. TAMDAR SOUNDINGS FROM FLIGHT PATHS FARTHER SOUTH AND EAST OF THE OFFICE ARE A BIT HIGHER...GENERALLY 1.3-1.6KFT AGL. GIVEN THE STRONG GRADIENT/WELL MIXED BOUNDARY LAYER AND LIMITED THERMAL ADVECTION...THIS RELATIVELY THIN WARM LAYER HAS NOT ERODED THROUGH EVAPORATIVE COOLING OR MELTING. EXPECT WE WILL CONTINUE TO HOVER RIGHT AROUND THE RAIN/SNOW THRESHOLD WITH THE NOD GOING TOWARD RAIN...AND WILL MAINTAIN THE CURRENT IDEA OF RAIN POSSIBLY MIXED WITH SNOW. WILL UPDATE TO TRIM BACK THE WEATHER GRIDS BASED ON LATEST RADAR TRENDS...BUT ALSO MAINTAIN CATEGORICAL POPS ACROSS THE FAR SOUTHEAST FOR A BIT LONGER INTO THE AFTERNOON. SATELLITE/METARS SHOW PLENTY OF DRY AIR WORKING IN ACROSS THE NORTH AND WEST CWA...SO SHOULD BE ABLE TO KEEP A SHARP CUTOFF TO THE PRECIP. && .AVIATION...625 AM EST SAT APR 2 2005 STRONGER DYNAMICS AND DEEPER MOISTURE TO REMAIN SOUTHEAST OF A FNT/LAN LINE. AS A RESULT PROLONGED MVFR CIGS AND VSBYS WILL BE CONFINED TO THE DTW AND DET TAFS...WITH A BRIEF PERIOD OF IFR IN RAIN AND SNOW FROM 12-18Z. BEST CHANCE FOR PRECIPITATION IN FNT BETWEEN 13-16Z...AND MBS SHOULD REMAIN PRECIPITATION FREE. SO WILL CONTINUE WITH VFR THROUGH THE PERIOD FOR MBS. LOW CLOUDS STRIP AWAY QUICKLY THIS AFTERNOON AS LOW DEEPENS EAST OF THE APPALACHIANS. MVFR CIGS SHOULD CLEAR FNT BY 18Z AND DTW BY 22Z. DEEP LOW PRESSURE WILL PRODUCE STRONG NORTH WINDS THROUGH THE PERIOD FOR ALL TAF SITES. ATMOSPHERE WILL BE WELL MIX WITH GUSTY WINDS REACHING THE SURFACE EVEN AT 12Z...SO DO NOT ANTICIPATE ANY LOW LEVEL WIND SHEAR AT THIS TIME. && .SHORT TERM...SATURDAY AND SATURDAY NIGHT...ISSUED AT 321 AM PRECIPITATION SHIELD AND COLDER CLOUD TOPS ON IR LOOP BEGINNING TO DRAW BACK TO THE WEST AS SURFACE LOW CONTINUES TO TRACK NORTHEAST INTO WEST VIRGINIA...AND THETA-E ADVECTION INCREASES ON THE NORTH SIDE OF THE LOW. ANTICIPATE PRECIPITATION TO STEADILY INCREASE OVER THE EASTERN HALF OF THE CWA THROUGH 15Z. NOT REAL IMPRESSED WITH DEFORMATION AXIS OVER THE WESTERN GREAT LAKES AS IR LOOP CONTINUES TO SHOW CLOUD TOP WARMING OVER THE WESTERN PORTION OF THE STATE. MODELS SHOW THIS FEATURE ROTATING SOUTHEAST INTO THE CWA BETWEEN 12-15Z AND 500 MB FGEN FIELD STRENGTHENING FOR A BRIEF TIME BETWEEN 12-15Z. LOOKS LIKE THE MODELS MAY BE TO AGGRESSIVE WITH DEFORMATION AXIS AND 500 MB FGEN THOUGH. FIRST SHORT TERM CONCERN WILL BE PRECIPITATION TYPE. MID LEVELS CONTINUE TO BE COLD ENOUGH FOR SNOW...HOWEVER IT SHOULD TAKE SEVERAL HOURS TO ERODE DEEP WARM LAYER BELOW 2500 FT. MODELS NOW SHOWING WET BULB TEMPERATURES ABOVE FREEZING FROM THE SURFACE THROUGH 2K FEET THROUGH 12Z...THEN SLOWLY ERODING BETWEEN 1K-2K FT THROUGH 18Z. SURFACE DEW POINTS HAVE ALSO CLIMBED INTO THE MID 30S ACROSS THE SOUTHEAST PORTION OF THE CWA IN AREA OF ONGOING PRECIPITATION...SO LATENT HEAT RELEASE MAY ALREADY BE HAVING AN IMPACT. THERE WILL BE A FIGHT BETWEEN THE LATENT HEAT RELEASE AND COOLING DUE TO MELTING...ESPECIALLY ACROSS THE FAR SOUTHEAST PORTION OF THE CWA IN REGION OF HEAVIER PRECIPITATION. THERMAL FIELD REMAINS HOMOGENEOUS THOUGH SO WILL NOT HAVE TO CONTEND WITH MUCH WARM AIR ADVECTION. A COMPLICATING FACTOR WILL BE INCREASING NORTHEAST FLOW OFF OF THE COOLER LAKES...WHICH WILL ALSO HINDER BOUNDARY LAYER WARMING. SO ALL THINGS CONSIDER...EVEN WITH A DEEP WARM LAYER TO BEGIN WITH...RAIN/SNOW MIX STILL LOOKS LIKE THE WAY TO GO AFTER 12Z...ESPECIALLY WITH THE HOMOGENEOUS THERMAL FIELD OVER THE CENTRAL GREAT LAKES. A THIS TIME WILL KEEP SNOW ACCUMULATIONS CONFINED TO LESS THAN AN INCH. THIS WILL HAVE TO BE WATCHED CAREFULLY ACROSS THE FAR SOUTHEAST PORTION OF THE CWA THOUGH. MODELS SHOWING A BRIEF PERIOD OF INCREASING 850-700 MB FGEN DRAWING NORTHWEST INTO THE FAR SOUTHEAST PORTION OF THE CWA BETWEEN 12-15Z...SO ANTICIPATE THIS WILL BE THE TIME FRAME FOR MOST SIGNIFICANT QPF AND POTENTIAL MIX WITH SNOW. UPPER JET DYNAMICS ALREADY WELL EAST OF THE CWA...AND MODELS SHOW SOME JET COUPLING ALONG THE EAST COAST THIS AFTERNOON AND RAPID DEEPENING OF SURFACE LOW. CURRENT OBSERVATIONS INDICATE THIS IS ALREADY HAPPENING...WITH LOW ALREADY DOWN TO 994 OVER SOUTHERN WEST VIRGINIA. AS A RESULT NORTHEAST WINDS WILL INCREASE RAPIDLY ACROSS THE CENTRAL GREAT LAKES SO WILL NEED GALE WARNINGS FROM SOUTHERN LAKE HURON SOUTHWARD BY 18Z. MODEL DIFFERENCE ARE MINOR IN THE FIRST 24 HOURS...WITH THE NAM AND RUC VERY SIMILAR OVER THE GREAT LAKES REGION...GFS APPEARS TO BE A LITTLE TO COLD WITH THE 850 MB THERMAL FIELD OVER WISCONSIN...SHOWING A LARGE AREA OF -5C...WITH COLDEST OBS ONLY -3C...NAM HAS DONE A MUCH BETTER JOB THERE...SO SHORT TERM FORECAST WILL LEAN MORE TOWARD A NAM SOLUTION. NAM QPF ALSO A LITTLE MORE ROBUST WITH QPF THROUGH 15Z...WHICH MATCHES UP BETTER WITH CURRENT 6 HOUR QPF TOTALS OVER THE FAR EASTERN PORTION OF THE CWA AND POINTS EAST. ALTHOUGH MODELS STRIP PRECIPITATION OUT OF THE CWA QUICKLY THIS EVENING...WILL CONTINUE WITH A MENTION OF CHANCE POPS EAST THROUGH 06Z...DUE TO UNCERTAINTY IN CYCLOGENESIS ALONG THE EAST COAST AND ASSOCIATED EASTWARD PROGRESSION OF LOW LEVEL CYCLONIC FLOW. && .LONG TERM...ISSUED AT 321 AM AS THE STORM SLOWLY PULLS AWAY...THERE WILL STILL BE PLENTY OF WIND ON SUNDAY. AREA WILL BE MIXING UP TO 2K TO 4K FEET...WHICH WILL HELP BRING DOWN WIND GUSTS UP TO 35 KTS. SUNSHINE WILL HELP GET THE MIXING GOING ON SUNDAY. ONLY SOME HI MOISTURE FROM THE DEPARTING SYSTEM ON SUNDAY TO GIVE THE EASTERN HALF OF THE CWA SOME CI. WITH THE STRONG NW WINDS...AND 80H TEMPS STILL AROUND 0C...WENT TOWARD THE COOLER NAM GUIDANCE NUMBERS...EVEN WITH PLENTY OF SUN. AFTER SUNDAY...DRY AIR IS IN PLACE RIGHT UNTIL TUESDAY...BESIDES SOME CI AHEAD OF THE NEXT SYSTEM ON MONDAY NIGHT. ENOUGH DRY AIR TO JUST GO WITH CLEAR AND SUNNY FORECAST SUNDAY NIGHT AND MONDAY. BY TUESDAY...MOISTURE POOLS ALONG THE WARM FRONT JUST SOUTH OF THE STATE SO EXPECT SOME PARTLY SUNNY CONDITIONS. JUST NOT ENOUGH FORCING TO GET ANYTHING OTHER THAN CLOUDS WITH THE WARM FRONT. THEN THE 00Z GFS IS SLOWER WITH THE NEXT SYSTEM...LEANING MUCH MORE TOWARD THE UKMET...ECMWF AND CANADIAN...WHICH IS WHAT WAS GOING IN THE FORECAST. SO NO REAL CHANGES FROM TUESDAY TO FRIDAY. DID TWEAK HIGH TEMPERATURES THOUGH...JUST A BIT WARMER AHEAD OF THE FRONT FOR TUESDAY AND WEDNESDAY...AND THEN A BIT COOLER BEHIND THE FRONT. && .DTX WATCHES/WARNINGS/ADVISORIES... .MI...NONE. .LAKE HURON...GALE WARNING...SOUTH HALF...THROUGH SUNDAY AFTERNOON. .LAKE ST CLAIR...GALE WARNING...THROUGH SUNDAY AFTERNOON. .MI WATERS OF LAKE ERIE...GALE WARNING...THROUGH SUNDAY AFTERNOON. && $$ BRAVENDER/GSS/RBP mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GAYLORD MI 1006 AM EST SAT APR 2 2005 .UPDATE...CLOUD COVER ASSOCIATED WITH THE DEVELOPING E COAST STORM IS JUST GRAZING THE FORECAST AREA. MOSTLY CLOUDY CONDITIONS PREVAIL EAST OF A LINE FROM HURON BEACH TO HTL...PARTLY TO MOSTLY SUNNY WEST. THERE IS A SMALL AREA OF MID CLOUDS GRAZING BY FAR WESTERN CHIP/MACK COUNTIES IN THE EASTERN UP. IT/S A BIT BRISK THIS MORNING IN THE SOUTHERN AND EASTERN ZONES WHERE THE PRESSURE GRADIENT IS TIGHTER...WINDIEST CONDITIONS ARE ALONG THE LAKE HURON SHORELINE. MID LEVEL DEFORMATION AXIS...BETWEEN UPPER LOWS NEAR JAMES BAY AND IN THE UPPER TN VALLEY...MARKS THE BOUNDARY BETWEEN CLOUDS AND SUN. NAM IS A LITTLE SLOWER THAN THE RUC TO MOVE THE DEFORMATION AXIS EAST...AND GIVEN SATELLITE TRENDS SLOWER IS BETTER. STILL...AS THE AFTERNOON GOES ON THE DEFORMATION AXIS WILL MOVE OUT ACROSS LAKE HURON. CLEARING WILL OCCUR...BUT A LITTLE SLOWER THAN EARLIER PLANNED. CURRENT OBS SUPPORT TWEAKING TEMPS UPWARD IN NE WIND DOWNSLOPE AREAS IN NW LOWER AND EASTERN UPPER MI. WILL GO A BIT COOLER NEAR LAKE HURON WITH A COLD ONSHORE WIND. ZOLTOWSKI && .PREV DISCUSSION ISSUED 317 AM SAT APR 2... STORM SYSTEM GETTING SPUN UP ACROSS THE OHIO VALLEY AS WV IMAGERY SHOWS UPPER LOW CLOSING OFF OVER EASTERN IA. 999MB SURFACE LOW ALONG WV/KY BORDER WITH A PAIR OF STRONG PRESSURE FALL CENTERS (5-6MB/3HR) ASSOCIATED WITH IT...ONE OVER OH AND A SECOND OVER THE CAROLINAS. SURFACE LOW WILL CONTINUE TO DEEPEN AND LIFT INTO OH THIS MORNING...BUT SECONDARY CYCLOGENESIS ALREADY OCCURRING OVER THE CAROLINAS WHERE SECOND PRESSURE FALL CENTER IS LOCATED AS UPPER LOW DIVES INTO THE SOUTHEASTERN U.S. THIS WILL BECOME THE MAIN SURFACE FEATURE AS IT LIFTS NORTH INTO PA BY TONIGHT...AND SLOWLY INTO THE NORTHEAST SUNDAY. SO FORECAST CONCERNS REVOLVE AROUND WHAT EFFECTS THIS DEVELOPING SYSTEM WILL HAVE ON NORTHERN MI THIS WEEKEND. TODAY...AREA RADARS SHOW PRECIP TRYING TO BACK INTO CENTRAL/SOUTHERN LOWER MI EARLY THIS MORNING AS MID LEVEL CIRCULATION TAKES SHAPE. 00Z APX/DTX RAOBS WERE DRY BELOW 700MB (10-20C DEW POINT DEPRESSIONS AT 850MB)...AND APPEARS CONTINUED ADVECTION OF LOW LEVEL DRY AIR FROM THE EAST HAS BEEN KEEPING MUCH PRECIP FROM REACHING THE GROUND OVER SOUTHERN LOWER. CI/AC SHIELD HAS OVERSPREAD ALL BUT FAR WESTERN PORTIONS OF MACKINAC/CHIPPEWA COUNTIES WHERE MID/UPPER LEVEL FLOW IS MORE FROM THE SOUTHWEST. MID LEVEL DEFORMATION AXIS ALREADY EVIDENT IN RADAR COMPOSITE RUNNING ACROSS SOUTHERN LAKE HURON/ SOUTHERN ONTARIO...AND THIS WILL BE THE KEY FOR NORTHERN MI TODAY. THIS FEATURE SET UP ACROSS THE NORTHERN HALF OF THE STATE ALONG WITH CONTINUED LOW LEVEL DRY AIR ADVECTION SHOULD KEEP MAIN PRECIP THREAT TO THE SOUTH. WILL KEEP AN EYE ON RADAR TRENDS THIS MORNING. THIS SET UP ALSO CONTRIBUTES TO INCREASING DEEP LAYER DOWNWARD FORCING TODAY WITH NORTHERN MI ENDING UP ON THE COOL SIDE OF STRONG LOW/MID LEVEL FRONTOGENESIS MAXIMUM TO THE SOUTHEAST. SO THICK AC/CI LAYER ACROSS THE AREA EARLY ON EXPECTED TO THIN OUT OVER ALL EXCEPT FAR NORTHEAST LOWER...LIKELY BY MID/LATE MORNING. THIS INCLUDES SOME ACCAS ACROSS WESTERN LAKE SUPERIOR/WESTERN UPPER WHICH MAY TRY TO DRIFT INTO EASTERN UPPER THIS MORNING. SO WILL TREND THE FORECAST TOWARD LESS CLOUD COVER AS THE DAY WEARS ON. TIGHTENING PRESSURE GRADIENT AND MIXING SHOULD RESULT IN A BREEZY DAY ACROSS MUCH OF THE AREA...WITH 20-30 MPH GUSTS EXPECTED DURING THE LATE MORNING/ AFTERNOON. TONIGHT...LOOKING AT A CLEAR/PARTLY CLOUDY NIGHT ACROSS NORTHERN MI AS EASTERN SYSTEM LIFTS NORTH THROUGH THE MID ATLANTIC STATES. NARROW WEDGE OF VERY DRY AIR FORECAST ACROSS THE AREA BETWEEN EXPANSIVE UPPER LOW TO THE EAST AND SHORT WAVE RIDGE AXIS POKING INTO THE WESTERN GREAT LAKES. EXPECT GUSTY WINDS FROM THE NORTH/ NORTHWEST TO CONTINUE OVERNIGHT ACROSS NORTHEAST LOWER. SUNDAY...ANOTHER DRY DAY EXPECTED WITH A GOOD DEAL OF SUN...PERHAPS SOME CI ACROSS NORTHEAST LOWER ROTATING AROUND EASTERN STORM SYSTEM. GFS TRIES TO SHOVE SOME HIGHER RH AROUND 850MB INTO THE AREA LATE IN THE DAY...LOOKS LIKE THE MODEL IS HAVING SOME LOW LEVEL MOISTURE ISSUES UPSTREAM (10-20F JUMP IN SURFACE DEW POINTS BETWEEN 12-18Z SUNDAY ACROSS MN/WI LOOKS SUSPICIOUS) SO WILL IGNORE THIS TREND. SUNDAY NIGHT ALSO LOOKS MAINLY CLEAR WITH SURFACE RIDGING OVERHEAD AND MID/UPPER LEVEL RIDGE AXIS UPSTREAM. ANOTHER BREEZY DAY EXPECTED SUNDAY...ESPECIALLY OVER EASTERN HALF OF THE FORECAST AREA ON THE BACK EDGE OF TIGHTER PRESSURE GRADIENT ASSOCIATED WITH SURFACE LOW LIFTING INTO NY...AND WITH 25-35KT WINDS WITHIN MIXED LAYER EXPECT GUSTS ALONG/EAST OF I-75 IN THE 30-40 MPH RANGE. WINDS WILL DIMINISH SUNDAY NIGHT AS SURFACE RIDGE AXIS BUILDS INTO THE STATE. MONDAY AND EXTENDED PERIODS...NO CHANGES MADE TO DRY MONDAY FORECAST AS AFOREMENTIONED MID LEVEL RIDGE AXIS STILL WEST OF THE STATE. JPB && .APX...WATCHES/WARNINGS/ADVISORIES...NONE. && $$ mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 625 AM EST SAT APR 2 2005 .AVIATION... STRONGER DYNAMICS AND DEEPER MOISTURE TO REMAIN SOUTHEAST OF A FNT/LAN LINE. AS A RESULT PROLONGED MVFR CIGS AND VSBYS WILL BE CONFINED TO THE DTW AND DET TAFS...WITH A BRIEF PERIOD OF IFR IN RAIN AND SNOW FROM 12-18Z. BEST CHANCE FOR PRECIPITATION IN FNT BETWEEN 13-16Z...AND MBS SHOULD REMAIN PRECIPITATION FREE. SO WILL CONTINUE WITH VFR THROUGH THE PERIOD FOR MBS. LOW CLOUDS STRIP AWAY QUICKLY THIS AFTERNOON AS LOW DEEPENS EAST OF THE APPALACHIANS. MVFR CIGS SHOULD CLEAR FNT BY 18Z AND DTW BY 22Z. DEEP LOW PRESSURE WILL PRODUCE STRONG NORTH WINDS THROUGH THE PERIOD FOR ALL TAF SITES. ATMOSPHERE WILL BE WELL MIX WITH GUSTY WINDS REACHING THE SURFACE EVEN AT 12Z...SO DO NOT ANTICIPATE ANY LOW LEVEL WIND SHEAR AT THIS TIME. && .SHORT TERM...SATURDAY AND SATURDAY NIGHT...ISSUED AT 321 AM PRECIPITATION SHIELD AND COLDER CLOUD TOPS ON IR LOOP BEGINNING TO DRAW BACK TO THE WEST AS SURFACE LOW CONTINUES TO TRACK NORTHEAST INTO WEST VIRGINIA...AND THETA-E ADVECTION INCREASES ON THE NORTH SIDE OF THE LOW. ANTICIPATE PRECIPITATION TO STEADILY INCREASE OVER THE EASTERN HALF OF THE CWA THROUGH 15Z. NOT REAL IMPRESSED WITH DEFORMATION AXIS OVER THE WESTERN GREAT LAKES AS IR LOOP CONTINUES TO SHOW CLOUD TOP WARMING OVER THE WESTERN PORTION OF THE STATE. MODELS SHOW THIS FEATURE ROTATING SOUTHEAST INTO THE CWA BETWEEN 12-15Z AND 500 MB FGEN FIELD STRENGTHENING FOR A BRIEF TIME BETWEEN 12-15Z. LOOKS LIKE THE MODELS MAY BE TO AGGRESSIVE WITH DEFORMATION AXIS AND 500 MB FGEN THOUGH. FIRST SHORT TERM CONCERN WILL BE PRECIPITATION TYPE. MID LEVELS CONTINUE TO BE COLD ENOUGH FOR SNOW...HOWEVER IT SHOULD TAKE SEVERAL HOURS TO ERODE DEEP WARM LAYER BELOW 2500 FT. MODELS NOW SHOWING WET BULB TEMPERATURES ABOVE FREEZING FROM THE SURFACE THROUGH 2K FEET THROUGH 12Z...THEN SLOWLY ERODING BETWEEN 1K-2K FT THROUGH 18Z. SURFACE DEW POINTS HAVE ALSO CLIMBED INTO THE MID 30S ACROSS THE SOUTHEAST PORTION OF THE CWA IN AREA OF ONGOING PRECIPITATION...SO LATENT HEAT RELEASE MAY ALREADY BE HAVING AN IMPACT. THERE WILL BE A FIGHT BETWEEN THE LATENT HEAT RELEASE AND COOLING DUE TO MELTING...ESPECIALLY ACROSS THE FAR SOUTHEAST PORTION OF THE CWA IN REGION OF HEAVIER PRECIPITATION. THERMAL FIELD REMAINS HOMOGENEOUS THOUGH SO WILL NOT HAVE TO CONTEND WITH MUCH WARM AIR ADVECTION. A COMPLICATING FACTOR WILL BE INCREASING NORTHEAST FLOW OFF OF THE COOLER LAKES...WHICH WILL ALSO HINDER BOUNDARY LAYER WARMING. SO ALL THINGS CONSIDER...EVEN WITH A DEEP WARM LAYER TO BEGIN WITH...RAIN/SNOW MIX STILL LOOKS LIKE THE WAY TO GO AFTER 12Z...ESPECIALLY WITH THE HOMOGENEOUS THERMAL FIELD OVER THE CENTRAL GREAT LAKES. A THIS TIME WILL KEEP SNOW ACCUMULATIONS CONFINED TO LESS THAN AN INCH. THIS WILL HAVE TO BE WATCHED CAREFULLY ACROSS THE FAR SOUTHEAST PORTION OF THE CWA THOUGH. MODELS SHOWING A BRIEF PERIOD OF INCREASING 850-700 MB FGEN DRAWING NORTHWEST INTO THE FAR SOUTHEAST PORTION OF THE CWA BETWEEN 12-15Z...SO ANTICIPATE THIS WILL BE THE TIME FRAME FOR MOST SIGNIFICANT QPF AND POTENTIAL MIX WITH SNOW. UPPER JET DYNAMICS ALREADY WELL EAST OF THE CWA...AND MODELS SHOW SOME JET COUPLING ALONG THE EAST COAST THIS AFTERNOON AND RAPID DEEPENING OF SURFACE LOW. CURRENT OBSERVATIONS INDICATE THIS IS ALREADY HAPPENING...WITH LOW ALREADY DOWN TO 994 OVER SOUTHERN WEST VIRGINIA. AS A RESULT NORTHEAST WINDS WILL INCREASE RAPIDLY ACROSS THE CENTRAL GREAT LAKES SO WILL NEED GALE WARNINGS FROM SOUTHERN LAKE HURON SOUTHWARD BY 18Z. MODEL DIFFERENCE ARE MINOR IN THE FIRST 24 HOURS...WITH THE NAM AND RUC VERY SIMILAR OVER THE GREAT LAKES REGION...GFS APPEARS TO BE A LITTLE TO COLD WITH THE 850 MB THERMAL FIELD OVER WISCONSIN...SHOWING A LARGE AREA OF -5C...WITH COLDEST OBS ONLY -3C...NAM HAS DONE A MUCH BETTER JOB THERE...SO SHORT TERM FORECAST WILL LEAN MORE TOWARD A NAM SOLUTION. NAM QPF ALSO A LITTLE MORE ROBUST WITH QPF THROUGH 15Z...WHICH MATCHES UP BETTER WITH CURRENT 6 HOUR QPF TOTALS OVER THE FAR EASTERN PORTION OF THE CWA AND POINTS EAST. ALTHOUGH MODELS STRIP PRECIPITATION OUT OF THE CWA QUICKLY THIS EVENING...WILL CONTINUE WITH A MENTION OF CHANCE POPS EAST THROUGH 06Z...DUE TO UNCERTAINTY IN CYCLOGENESIS ALONG THE EAST COAST AND ASSOCIATED EASTWARD PROGRESSION OF LOW LEVEL CYCLONIC FLOW. && .LONG TERM...ISSUED AT 321 AM AS THE STORM SLOWLY PULLS AWAY...THERE WILL STILL BE PLENTY OF WIND ON SUNDAY. AREA WILL BE MIXING UP TO 2K TO 4K FEET...WHICH WILL HELP BRING DOWN WIND GUSTS UP TO 35 KTS. SUNSHINE WILL HELP GET THE MIXING GOING ON SUNDAY. ONLY SOME HI MOISTURE FROM THE DEPARTING SYSTEM ON SUNDAY TO GIVE THE EASTERN HALF OF THE CWA SOME CI. WITH THE STRONG NW WINDS...AND 80H TEMPS STILL AROUND 0C...WENT TOWARD THE COOLER NAM GUIDANCE NUMBERS...EVEN WITH PLENTY OF SUN. AFTER SUNDAY...DRY AIR IS IN PLACE RIGHT UNTIL TUESDAY...BESIDES SOME CI AHEAD OF THE NEXT SYSTEM ON MONDAY NIGHT. ENOUGH DRY AIR TO JUST GO WITH CLEAR AND SUNNY FORECAST SUNDAY NIGHT AND MONDAY. BY TUESDAY...MOISTURE POOLS ALONG THE WARM FRONT JUST SOUTH OF THE STATE SO EXPECT SOME PARTLY SUNNY CONDITIONS. JUST NOT ENOUGH FORCING TO GET ANYTHING OTHER THAN CLOUDS WITH THE WARM FRONT. THEN THE 00Z GFS IS SLOWER WITH THE NEXT SYSTEM...LEANING MUCH MORE TOWARD THE UKMET...ECMWF AND CANADIAN...WHICH IS WHAT WAS GOING IN THE FORECAST. SO NO REAL CHANGES FROM TUESDAY TO FRIDAY. DID TWEAK HIGH TEMPERATURES THOUGH...JUST A BIT WARMER AHEAD OF THE FRONT FOR TUESDAY AND WEDNESDAY...AND THEN A BIT COOLER BEHIND THE FRONT. && .DTX WATCHES/WARNINGS/ADVISORIES... .MI...NONE. .LAKE HURON...GALE WARNING...SOUTH HALF...THROUGH EARLY SUNDAY AFTERNOON. .LAKE ST CLAIR...GALE WARNING...THROUGH EARLY SUNDAY AFTERNOON. .MI WATERS OF LAKE ERIE...GALE WARNING...THROUGH EARLY SUNDAY AFTERNOON. && $$ GSS/RBP mi AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE BUFFALO NY 1100 PM EST SAT APR 2 2005 .UPDATE... WILL BE ISSUING WINTER STORM WARNING OVERNIGHT AND SUNDAY FOR THE FAR WESTERN COUNTIES AS A RESULT OF RADAR DEPICTION OF DEFORMATION ZONE SETTING UP OVER THE FAR WESTERN COUNTIES. THIS WILL INCLUDE NIAGARA...ERIE...CHAUTAUQUA AND CATTARAUGUS. WILL GO WITH 3 TO 6 INCHES IN THESE AREAS OVERNIGHT WITH ANOTHER 3 TO 6 INCHES FOR SUNDAY. AMOUNTS WILL ALSO BE RASIED FOR THE ADVISORY AREA OF ORLEANS..GENESEE...WYOMING AND ALLEGANY. PREVIOUS DISCO FOUND BELOW. RSH .FROM 10 PM... TWO DISTINCT WEATHER REGIMES TONIGHT...EACH WITH THEIR OWN CONCERNS TO ADDRESS. LETS BEGIN WITH THE FLOODING. THE STACKED STORM SYSTEM SPINNING OVER EASTERN PENNSYLVANIA HAS BEEN CIRCULATING COPIOUS AMOUNTS OF ATLANTIC MOISTURE BACK ACROSS WESTERN AND NORTH CENTRAL NEW YORK FOR OVER 24 HOURS. RUNNING RAINFALL TOTALS (AS OF THE WRITING OF THIS AFD) RANGE FROM ONE TO TWO INCHES ACROSS THE FORECAST AREA. OVER THE FINGER LAKES AND EASTERN LAKE ONTARIO REGIONS...THE BULK OF THIS RAIN HAS FALLEN SINCE 18Z. DEEP VERTICAL MOTION DEPICTED WITHIN AN AGEOSTROPHIC CIRCULATION CROSS SECTION ACROSS THE FINGER LAKES UNCOVERED VERY DEEP (30K FT OR ROUGHLY 700MB) LIFT SUPPLIED FROM A COUPLED H25 JET. THIS PROCESS HAS BEEN VERY EFFICIENT AT PRODUCING AN EXTENDED PERIOD OF MODERATE TO HEAVY RAIN FROM EASTERN PA TO THE FINGER LAKES BETWEEN 21-02Z... BUT AS MODELS HAD PREDICTED...THE LIFTING JETS ARE DISPLACING THE EFFECTS OF THE COUPLED JET AND THE CORRESPONDING RAIN IS FALLING APART IN THAT PARTICULAR REGION. AS A RESULT...THE PREVIOUSLY ISSUED FLOOD WARNINGS FOR PARTS OF THE FINGER LAKES AND EASTERN LAKE ONTARIO REGIONS WILL BE ALLOWED TO EXPIRE AT 04Z. WE WILL HOWEVER...KEEP THE FLOOD WATCH IN PLACE FOR ALL OF WESTERN AND NORTH CENTRAL NEW YORK THROUGH 23Z (6PM EDT) SUNDAY. NEWLY ISSUED RIVER FLOOD WARNINGS ARE DETAILED BELOW IN THE HYDRO DISCUSSION. THE STEADIEST PCPN WILL THEN BE FOUND OVER THE FAR WESTERN COUNTIES WHERE A NEW DEFORMATION ZONE IS TRYING TO GET ESTABLSHED. RUC40 OMEGA AND PCPN FORECASTS PLACE THE MOST LIKELY AREA OF CONCERN OVER THE IAG FRONTIER AND LAKE ERIE. WHILE AN EASTERLY FLOW HAS MODERATED SFC-850MB TEMPS EAST OF LK ONTARIO...A NORTH TO NORTHEAST FLOW AT A SIMILAR LEVEL HAS RESULTED IN COLD ADVECTION OVER THE FAR WESTERN COUNTIES. A POINT SOUNDING SOUTH OF ROC SHOWED CONTINUED COLD ADVECTION AT H85...SUGGESTING THAT THE PCPN WILL CHANGE OVER TO SNOW AND/OR SLEET AS FAR EAST AS ROC. MIXED PCPN HAS ALREADY CHANGED TO SNOW FOR PLACES LIKE BUF AND IAG. A WINTER WEATHER ADVISORY IS ALREADY IN PLACE FOR THE IAG FRONTIER AND WESTERN SOUTHERN TIER...BUT WILL MOST LIKELY OPEN UP THE CURRENT SNOWFALL RANGE FOR THE OVERNIGHT PERIOD TO ACCOUNT FOR MODELS DEPICTION OF A STRENGTHENING DEFORMATION ZONE OVER THIS PARTICULAR REGION. RSH && .SHORT TERM (SUNDAY THROUGH MONDAY)... MIXED PCPN OVER THE GENESEE VALLEY SUNDAY MORNING WILL GRADUALLY WORK TO THE EAST DURING SUNDAY AND SUNDAY NIGHT S COLD ADVECTION SPREADS EAST. THE LOW WILL GRADUALLY LIFT NORTHEAST ALONG THE ST.LAWRENCE VALLEY WITH WRAP AROUND PRECIP WINDING DOWN SUNDAY NIGHT AND EARLY MONDAY AS SURFACE RIDGE BUILDS IN. && .LONG TERM (TUESDAY THROUGH SATURDAY)... CLOSED LOW OVER THE LOWER SAINT LAWRENCE RIVER WILL SLOWLY FILL AND FINALLY GET PUSHED OUT TO SEA AS A SURFACE HIGH AND UPPER RIDGE BUILD OVER THE GREAT LAKES AND MID ATLANTIC STATES ON TUESDAY AND EARLY WEDNESDAY. UPPER RIDGE ACROSS THE REGION ON WEDNESDAY WILL WARM TEMPS INTO THE 60S FOR MUCH OF THE FORECAST AREA. SOUTHERLY WINDS WILL ENHANCE TEMPS AS WELL WITH DOWNSLOPING OVER THE WEST. THE RIDGE SHIFTS TO THE EAST OF THE AREA WED NIGHT AS PACIFIC CUTOFF TRACKS ACROSS THE SOUTHERN PLAINS AND A SPEED MAX DIVES SOUTHWARD OVER THE PRAIRIE PROVINCES. THE NORTHERN LOW DEEPENS SHARPLY AND PHASES WITH THE SOUTHERN LOW...ABSORBING IT INTO THE DEEPENING TROUGH IN THE PROCESS. A SLOW MOVING COLD FRONT...WITH A SERIES OF SURFACE WAVES ATTACHED...MOVES ACROSS THE STATE ON THURSDAY AND EARLY FRIDAY...STALLING ACROSS THE STATE ON FRIDAY. THE UPPER CUTOFF LOW SAGS SOUTH ACROSS THE CENTRAL GREAT LAKES AS THE TROUGH BECOMES NEGATIVELY TILTED. THIS HOLDS A STEADY STREAM OF PRECIP ACROSS NEW YORK STATE FROM MID THURSDAY THROUGH SATURDAY. HYDRO ISSUES WILL AGAIN BECOME A CONCERN. && .AVIATION... IFR TO LIFR WILL PERSIST ACROSS THE ENTIRE AREA IN RAIN AND SNOW THROUGH SUNDAY. && .MARINE... NORTHERLY WINDS ON LAKE ONTARIO OF 30 KNOTS WILL GRADUALLY SUBSIDE TO 15 TO 25 KNOTS SUNDAY MORNING AND THEN TEND TO BACK NORTHWEST LATER IN THE DAY. WAVES OF 5 TO 8 FEET WILL ONLY SLOWLY SUBSIDE SUNDAY. && .HYDRO... QUITE AN EVENT FOR OUR REGION. DRENCHING RAINS OF 1.5 TO 2.5 INCHES EAST OF THE GENESEE RIVER WITH WIDESPREAD LOCAL FLOODING AND 1 TO 1.5 INCHES TO THE WEST. WET SNOW MIXED IN AT TIMES OVER FAR WEST ALL DAY. WITH BEST DYNAMICS HAVING LIFTED NORTH OF OUR REGION LATE THIS EVENING...EXPECT ONLY LIGHT RAIN FROM GEN VALLEY EAST SO WILL ALLOW GENERAL FLOOD WARNING TO EXPIRE. FURTHER WEST...MOST OF PRECIP WILL FALL AS SNOW REST OF NIGHT INTO SUNDAY SO LITTLE IF ANY MORE RUNOFF. BUT...WILL HOLD ONTO FLOOD WATCH THRU SUNDAY FOR ANY LEFTOVERS. AS FOR RIVERS AND CREEKS...GOOD COORDINATION WITH RFCS TONIGHT AND BOTH ISSUED NEW RUNS AT 00Z (THANKS). WE WILL BE HOISTING WARNINGS FOR THE BLACK AND OATKA CREEKS IN ROCHESTER AREA...AND A LONGER TERM WARNING FOR BLACK RIVER EAST OF LAKE ONTARIO. SEVERAL OTHER WATERWAYS WILL GET TO BANKFUL BUT WILL HOLD OFF ON FLOOD WARNINGS AT THIS TIME AS THEY SHOULD CREST JUST BELOW FLOOD STAGE. THIS INCLUDES UPPER GENESEE AND ALLEGHENY RIVERS AND TONAWANDA CREEK. WE WILL MONITOR THESE CLOSELY THROUGH THE NIGHT. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...WINTER STORM WARNING OVERNIGHT AND SUNDAY NYZ001-010-019-020-085. WINTER WEATHER ADVISORY OVERNIGHT AND SUNDAY NYZ002-011-012-021. FLOOD WATCH THROUGH SUNDAY NYZ001>008-010>014-019>021-085. .MARINE...NONE. && UPDATE...RSH SHORT TERM...JML LONG TERM...WCH AVIATION/MARINE/HYDRO...SFM ny AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE BUFFALO NY 950 PM EST SAT APR 2 2005 .UPDATE... TWO DISTINCT WEATHER REGIMES TONIGHT...EACH WITH THEIR OWN CONCERNS TO ADDRESS. LETS BEGIN WITH THE ONE WITH THE LARGEST IMPACT...THAT BEING FLOODING. THE STACKED STORM SYSTEM SPINNING OVER EASTERN PENNSYLVANIA HAS BEEN CIRCULATING COPIOUS AMOUNTS OF ATLANTIC MOISTURE BACK ACROSS WESTERN AND NORTH CENTRAL NEW YORK FOR OVER 24 HOURS. RUNNING RAINFALL TOTALS (AS OF THE WRITING OF THIS AFD) RANGE FROM ONE TO TWO INCHES ACROSS THE FORECAST AREA. OVER THE FINGER LAKES AND EASTERN LAKE ONTARIO REGIONS...THE BULK OF THIS RAIN HAS FALLEN SINCE 18Z. DEEP VERTICAL MOTION DEPICTED WITHIN AN AGEOSTROPHIC CIRCULATION CROSS SECTION ACROSS THE FINGER LAKES UNCOVERED VERY DEEP (30K FT OR ROUGHLY 700MB) LIFT SUPPLIED FROM A COUPLED H25 JET. THIS PROCESS HAS BEEN VERY EFFICIENT AT PRODUCING AN EXTENDED PERIOD OF MODERATE TO HEAVY RAIN FROM EASTERN PA TO THE FINGER LAKES BETWEEN 21-02Z... BUT AS MODELS HAD PREDICTED...THE LIFTING JETS ARE DISPLACING THE EFFECTS OF THE COUPLED JET AND THE CORRESPONDING RAIN IS FALLING APART IN THAT PARTICULAR REGION. AS A RESULT...THE PREVIOUSLY ISSUED FLOOD WARNINGS FOR PARTS OF THE FINGER LAKES AND EASTERN LAKE ONTARIO REGIONS WILL BE ALLOWED TO EXPIRE AT 04Z. WE WILL HOWEVER...KEEP THE FLOOD WATCH IN PLACE FOR ALL OF WESTERN AND NORTH CENTRAL NEW YORK THROUGH 23Z (6PM EDT) SUNDAY. NEWLY ISSUED RIVER FLOOD WARNINGS ARE DETAILED BELOW IN THE HYDRO DISCUSSION. THE STEADIEST PCPN WILL THEN BE FOUND OVER THE FAR WESTERN COUNTIES WHERE A NEW DEFORMATION ZONE IS TRYING TO GET ESTABLSHED. RUC40 OMEGA AND PCPN FORECASTS PLACE THE MOST LIKELY AREA OF CONCERN OVER THE IAG FRONTIER AND LAKE ERIE. WHILE AN EASTERLY FLOW HAS MODERATED SFC-850MB TEMPS EAST OF LK ONTARIO...A NORTH TO NORTHEAST FLOW AT A SIMILAR LEVEL HAS RESULTED IN COLD ADVECTION OVER THE FAR WESTERN COUNTIES. A POINT SOUNDING SOUTH OF ROC SHOWED CONTINUED COLD ADVECTION AT H85...SUGGESTING THAT THE PCPN WILL CHANGE OVER TO SNOW AND/OR SLEET AS FAR EAST AS ROC. MIXED PCPN HAS ALREADY CHANGED TO SNOW FOR PLACES LIKE BUF AND IAG. A WINTER WEATHER ADVISORY IS ALREADY IN PLACE FOR THE IAG FRONTIER AND WESTERN SOUTHERN TIER...BUT WILL MOST LIKELY OPEN UP THE CURRENT SNOWFALL RANGE FOR THE OVERNIGHT PERIOD TO ACCOUNT FOR MODELS DEPICTION OF A STRENGTHEING DEFORMATION ZONE OVER THIS PARTICULAR REGION. RSH && .SHORT TERM (SUNDAY THROUGH MONDAY)... MIXED PCPN OVER THE GENESEE VALLEY SUNDAY MORNING WILL GRADUALLY WORK TO THE EAST DURING SUNDAY AND SUNDAY NIGHT S COLD ADVECTION SPREADS EAST. THE LOW WILL GRADUALLY LIFT NORTHEAST ALONG THE ST.LAWRENCE VALLEY WITH WRAP AROUND PRECIP WINDING DOWN SUNDAY NIGHT AND EARLY MONDAY AS SURFACE RIDGE BUILDS IN. && .LONG TERM (TUESDAY THROUGH SATURDAY)... CLOSED LOW OVER THE LOWER SAINT LAWRENCE RIVER WILL SLOWLY FILL AND FINALLY GET PUSHED OUT TO SEA AS A SURFACE HIGH AND UPPER RIDGE BUILD OVER THE GREAT LAKES AND MID ATLANTIC STATES ON TUESDAY AND EARLY WEDNESDAY. UPPER RIDGE ACROSS THE REGION ON WEDNESDAY WILL WARM TEMPS INTO THE 60S FOR MUCH OF THE FORECAST AREA. SOUTHERLY WINDS WILL ENHANCE TEMPS AS WELL WITH DOWNSLOPING OVER THE WEST. THE RIDGE SHIFTS TO THE EAST OF THE AREA WED NIGHT AS PACIFIC CUTOFF TRACKS ACROSS THE SOUTHERN PLAINS AND A SPEED MAX DIVES SOUTHWARD OVER THE PRAIRIE PROVINCES. THE NORTHERN LOW DEEPENS SHARPLY AND PHASES WITH THE SOUTHERN LOW...ABSORBING IT INTO THE DEEPENING TROUGH IN THE PROCESS. A SLOW MOVING COLD FRONT...WITH A SERIES OF SURFACE WAVES ATTACHED...MOVES ACROSS THE STATE ON THURSDAY AND EARLY FRIDAY...STALLING ACROSS THE STATE ON FRIDAY. THE UPPER CUTOFF LOW SAGS SOUTH ACROSS THE CENTRAL GREAT LAKES AS THE TROUGH BECOMES NEGATIVELY TILTED. THIS HOLDS A STEADY STREAM OF PRECIP ACROSS NEW YORK STATE FROM MID THURSDAY THROUGH SATURDAY. HYDRO ISSUES WILL AGAIN BECOME A CONCERN. && .AVIATION... IFR TO LIFR WILL PERSIST ACROSS THE ENTIRE AREA IN RAIN AND SNOW THROUGH SUNDAY. && .MARINE... NORTHERLY WINDS ON LAKE ONTARIO OF 30 KNOTS WILL GRADUALLY SUBSIDE TO 15 TO 25 KNOTS SUNDAY MORNING AND THEN TEND TO BACK NORTHWEST LATER IN THE DAY. WAVES OF 5 TO 8 FEET WILL ONLY SLOWLY SUBSIDE SUNDAY. && .HYDRO... QUITE AN EVENT FOR OUR REGION. DRENCHING RAINS OF 1.5 TO 2.5 INCHES EAST OF THE GENESEE RIVER WITH WIDESPREAD LOCAL FLOODING AND 1 TO 1.5 INCHES TO THE WEST. WET SNOW MIXED IN AT TIMES OVER FAR WEST ALL DAY. WITH BEST DYNAMICS HAVING LIFTED NORTH OF OUR REGION LATE THIS EVENING...EXPECT ONLY LIGHT RAIN FROM GEN VALLEY EAST SO WILL ALLOW GENERAL FLOOD WARNING TO EXPIRE. FURTHER WEST...MOST OF PRECIP WILL FALL AS SNOW REST OF NIGHT INTO SUNDAY SO LITTLE IF ANY MORE RUNOFF. BUT...WILL HOLD ONTO FLOOD WATCH THRU SUNDAY FOR ANY LEFTOVERS. AS FOR RIVERS AND CREEKS...GOOD COORDINATION WITH RFCS TONIGHT AND BOTH ISSUED NEW RUNS AT 00Z (THANKS). WE WILL BE HOISTING WARNINGS FOR THE BLACK AND OATKA CREEKS IN ROCHESTER AREA...AND A LONGER TERM WARNING FOR BLACK RIVER EAST OF LAKE ONTARIO. SEVERAL OTHER WATERWAYS WILL GET TO BANKFUL BUT WILL HOLD OFF ON FLOOD WARNINGS AT THIS TIME AS THEY SHOULD CREST JUST BELOW FLOOD STAGE. THIS INCLUDES UPPER GENESEE AND ALLEGHENY RIVERS AND TONAWANDA CREEK. WE WILL MONITOR THESE CLOSELY THROUGH THE NIGHT. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...FLOOD WARNING THROUGH 11 PM EST NYZ004>008-014. FLOOD WATCH THROUGH SUNDAY NYZ001>008-010>014-019>021-085. WINTER STORM WEATHER ADVISORY OVERNIGHT AND SUNDAY NYZ001-002-010>012-019>021-085 .MARINE...NONE. && UPDATE...RSH SHORT TERM...JML LONG TERM...WCH AVIATION/MARINE/HYDRO...SFM ny AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON OH 1050 AM EST SAT APR 2 2005 .SHORT TERM (REST OF TODAY)... WILL SEND OUT UPDATE WITHIN THE HOUR FOR RAIN/SNOW DEFINITIONS. RUC MDL SOUNDINGS PICK UP MORE PERSISTENT SNOW IN CNTRL OHIO WTH SFC TEMPS BELWO 35...WTH MOSTLY RA ELSEWHERE. ILN CURRENTLY MIXING IN SOME SN...BUT STILL MOSTLY RAIN. WILL HIT SN A LITTLE HARDER FOR CNTRL OHIO...BUT STILL KEEP LESS THAN AN INCH OF ACCUM. BACK EDGE OF PRECIP SHOULD WORK INTO FA BEGINNING EARLY AFTERNOON...SO ADDITIONAL UPDATE MAY BE NEEDED EARLY THIS AFTERNOON. .PRECIOUS DISCUSSION... (ISSUED 645 AM EST SAT APR 2 2005) AVIATION (12Z-12Z)... SURFACE LOW PRESSURE CENTERED OVER WEST VIRGINIA PAN HANDLE WILL TRACK SLOWLY EAST TODAY. 500 MB LOW IS CURRENTLY DROPPING SOUTH INTO KENTUCKY, WHICH IS ENHANCING WRAP AROUND PRECIP ON THE BACK OF THE SURFACE LOW. LIGHT SNOW IS OCCURRING AT DAY EVEN WITH TEMP AT 37. REST OF AREA IS REPORTING LIGHT RAIN. SLOW PROGRESS OF LOW MEANS PRECIP WILL CONTINUE INTO EVENING. CEILINGS HAVE FALLEN TO MVFR AND WILL REMAIN SO UNTIL TONIGHT. VISIBILITIES ARE GENERALLY VFR BUT STILL EXPECT MVFR LATER THIS MORNING. WIND GUSTS OVER 30 KTS WILL OCCUR THROUGH MUCH OF THE FORECAST IN THE TIGHT GRADIENT BEHIND THE SURFACE LOW. CLEARING WILL OCCUR LATE TONIGHT AFTER THE LOW TRACKS TO THE EAST COAST. && .SHORT TERM (TODAY THROUGH MONDAY)... AMPLIFIED UPPER LEVEL FLOW PATTERN WITH SHARP TROF OVER THE MS VLY CLOSING OFF OVER THE OH VALLEY THIS MORNING AND PIVOTING EWD INTO VA BY EVE AND THEN INTO THE MID ATLANTIC SUNDAY. 8H LOW TO TRACK ACRS SE OH EARLY TDA WITH AXIS OF FAVORABLE LOW LEVEL CONVERGENCE PIVOTING AROUND BACK SIDE INTO WRN OH. FAVORABLE FRONTOGENESIS IS INDICATED BTWN 600-650 MB FROM W CNTRL OH THRU THE MIAMI VALLEY. EXPECT TO SEE ENHANCED WRAP AROUND PRECIP ACRS THE AREA INTO THE EVE HOURS. ETA MODEL CONTS TO BE COLDER MODEL BUT IS NOT THE FAVORED SOLN. BOUNDARY LAYER STARTS OUT TOO WARM FOR SNOW WITH A FREEZING LEVEL ABOVE 1000 FEET. PREFER A SOLN CLOSER TO GFS. HAVE MODIFIED GFS THICKNESSES SLIGHTLY COOLER TO ALLOW A MIX WITH SNOW MAINLY THIS MORNING WHERE MORE FAVORABLE LIFT IS EXPECTED IN THE W. ANY SNOW ACCUMULATION IS EXPECTED TO BE LESS THAN AN INCH WITH THE WARM GROUND. REGARDING FLOOD WATCH...3 HOUR RAINFALL AMOUNTS HAVE BEEN BETWEEN .1 AND .3 INCHES WELL SHORT OF 3 HOUR FFG VALUES WHICH ARE AROUND ONE INCH. WITH DRY SLOT WORKING INTO FFA AREA DO NOT EXPECT TO SEE WIDESPREAD FLOODING. SOME MINOR RIVER FLOODING WL BE POSSIBLE DUE TO HI LEVELS OF FLOW BUT SINCE COUNTY FLOODING IS NOT ANTICIPATED HAVE DROPPED THE WATCH. FOCUS SHIFTS TO HIGH WIND POTENTIAL. AS DEEP SFC LOW PRESS SHIFTS TO THE EAST COAST THE PRESSURE GRADIENT INCREASES ACROSS OHIO. NRLY 925 MB WINDS ARE EXPECTED TO INCREASE TO 35 TO 40KTS AND CONTINUE INTO TONIGHT. EXPECT TO SEE SFC WINDS INCREASE TO 25 TO 35 MPH WITH WIND GUSTS TO 45 MPH. THEREFORE...HAVE PUT UP A WIND ADVSY FOR THE ENTIRE CWA UNTIL 6 AM SUNDAY. AS UPPER LOW LIFTS NE INTO NEW ENGLAND RDGG BEGINS TO BUILD INTO MS VLY SUNDAY INTO MON AND THEN BECOMES CENTERED OVER OH TUE. THIS WL OFFER DRY WX CONDITIONS WITH A WARMING TREND. && .PREVIOUS DISCUSSION... (ISSUED 310 PM EST FRI APR 2005) LONG TERM (MONDAY THROUGH FRIDAY)... EARLY PORTION OF EXTENDED WILL REMAIN DRY AS SFC HIGH REMAINS IN PLACE AND UPPER LEVEL RIDGE BUILDS IN. SFC WARM FRONT LIFTS ACROSS CWA EARLY TUESDAY. ISENTROPIC LIFT IS WEAK...SO WILL KEEP THIS PERIOD DRY. LATEST GFSLR HAS NEXT LOW PRESSURE SYSTEM FOR MIDDLE OF NEXT WEEK BROADER AND WEAKER. LATEST ECMWF LOOKS SIMILAR TO YESTERDAYS GFSLR. THIS MESHES WITH CURRENT HPC FORECAST SO HAVE TRENDED TOWARD THIS SOLUTION. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...WIND ADVISORY FOR OHZ026-034-035-042>046-051>056-060>065- 070>074-077>082-088 FROM 1 PM SATURDAY TO 6 AM SUNDAY. KY...WIND ADVISORY FOR KYZ089>100 FROM 1 PM SATURDAY TO 6 AM SUNDAY. IN...WIND ADVISORY FOR INZ050-058-059-066-073>075-080 FROM 1 PM SATURDAY TO 6 AM SUNDAY. && $$ oh AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE PITTSBURGH PA 932 PM EST SAT APR 2 2005 .SHORT TERM (REST OF TODAY THROUGH SUNDAY)... MADE UPDATE AS RECENT RADAR AND SATELLITE DATA SHOW PIVOT POINT OF DEFORMATION LIFT ZONE STILL OVER BUTLER COUNTY PA...WITH SPOTTER REPORTS OF 3 TO 5 INCH SLUSHY SNOW ACCUMULATIONS. RUC MODEL SHOWS THE DEFORMATION LIFT ZONE REMAINING OVER WESTERN PA...SO ADDITIONAL ACCUMULATIONS POSSIBLE WITH ADDITIONAL AREAS GETTING SLUSHY SNOW AMOUNTS IN THE 2 TO 4 INCH RANGE. PER NAM MODEL SOUNDINGS...WINDS CAN GUST OVER 40 KTS (45 MPH) LATE TONIGHT INTO MIDDAY SUNDAY...SO THE WIND ADVISORY MAINTAINED. && .PREVIOUS DISCUSSION... (ISSUED 315 PM EST SAT APR 2 2005) SHORT TERM (TONIGHT THROUGH MONDAY NIGHT)... SURFACE LOW HAS CONSOLIDATED TO THE EAST AND WILL DEEPEN THROUGH SUNDAY WITH STRONG WINDS EXPECTED TO DEVELOP THIS EVENING AND CONTINUE THROUGH SUNDAY. WILL KEEP WIND ADVISORY AS IS. LATER SHIFTS MAY NEED TO DECIDE IF UPGRADE TO HIGH WIND WARNING NEEDED FOR RIDGES. BACKLASH RAIN/SNOW WILL MOVE BACK EAST ACROSS CWA TONIGHT WITH COLDER AIR WRAPPING IN FROM WEST AND SOUTHWEST CHANGING RAIN TO SNOW ACROSS CWA. MODELS IN FAIRLY GOOD AGREEMENT ON PLACEMENT OF QPF WITH USUAL TIMING DIFFERENCES. WILL GO WITH A WINTER STORM WARNING FOR SOUTHERN RIDGES AND WV MTNS/GARRETT MD LATER TONIGHT INTO MIDDAY SUNDAY WITH 5-9 INCHES ESPECIALLY HIGHER ELEVATIONS. REMAINDER RIDGES AND NRN TIER OF CWA WILL BE CLOSE TO BEST DEFORMATION ZONE AND WENT WITH ADVISORY FOR 4-6 AS WARM GROUND SHOULD HELP KEEP ACCUMULATIONS DOWN SOMEWHAT. WHILE RAINFALL THIS EVENING IN THE NORTH WILL HAVE TO BE MONITORED CHANCES OF SIGNIFICANT FLOODING DECREASING THROUGH EVENING AND WILL CANCEL FLOOD WATCH. LONG TERM (TUESDAY THROUGH SATURDAY)... WILL CONTINUE WITH DRY FORECAST FOR TUESDAY WITH WARM ADVECTION KICKING IN LATE IN DAY. SEPARATE NORTHERN AND SOUTHERN BRANCH SYSTEMS SHOULD MERGE INTO ONE LOW OVER OHIO VALLEY DURING THURSDAY. THIS COMBINED SYSTEM SHOULD TRACK NORTHEAST INTO SOUTHERN NEW ENGLAND BY SATURDAY. WILL MENTION CHANCE POPS FROM LATE WEDNESDAY THROUGH FRIDAY NIGHT. AVIATION... MVFR CONDITIONS WILL CONTINUE THROUGH THE REST OF THIS AFTERNOON...OCCASIONALLY LOWERING TO IFR IN RAIN AND FOG. SURFACE WINDS WILL BECOME NORTHWEST LATE THIS AFTERNOON AND EVENING AND BECOMING QUITE STRONG AS A SURFACE LOW CONTINUES TO DEVELOP OVER VIRGINIA. EXPECT SUSTAINED WINDS AROUND 25 KT WITH GUSTS TO 45 KT AT TIMES OVERNIGHT INTO SUNDAY. GENERALLY IFR CONDITIONS ARE FORECAST TONIGHT AS RAIN CHANGES OVER TO SNOW. CONDITIONS SHOULD IMPROVE TO MVFR OVER EAST CENTRAL OHIO DURING SUNDAY MORNING. PBZ WATCHES/WARNINGS/ADVISORIES... MD...WIND ADVISORY FOR MDZ001 FROM 8 PM SATURDAY TO 7 PM SUNDAY. ...WINTER STORM WARNING FOR MDZ001 FROM MIDNIGHT SUNDAY TO NOON SUNDAY. OH...WIND ADVISORY FOR OHZ039-OHZ040-OHZ041-OHZ048-OHZ049-OHZ050- OHZ057-OHZ058-OHZ059-OHZ068-OHZ069 FROM 8 PM SATURDAY TO 7 PM SUNDAY. PA...WIND ADVISORY FOR PAZ007-PAZ008-PAZ009-PAZ013-PAZ014-PAZ015- PAZ016-PAZ020-PAZ021-PAZ022-PAZ023-PAZ029-PAZ030-PAZ031- PAZ032 FROM 8 PM SATURDAY TO 7 PM SUNDAY. ...WINTER WEATHER ADVISORY FOR PAZ007-PAZ008-PAZ009-PAZ015-PAZ016- PAZ023 FROM MIDNIGHT SUNDAY TO NOON SUNDAY. ...WINTER STORM WARNING FOR PAZ030-PAZ032 FROM MIDNIGHT SUNDAY TO NOON SUNDAY. WV...WIND ADVISORY FOR WVZ001-WVZ002-WVZ003-WVZ004-WVZ012-WVZ021- WVZ022-WVZ023-WVZ041 FROM 8 PM SATURDAY TO 7 PM SUNDAY. ...WINTER STORM WARNING FOR WVZ023-WVZ041 FROM MIDNIGHT SUNDAY TO NOON SUNDAY. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...WIND ADVISORY FOR MDZ001 FROM 9 PM SATURDAY TO 7 PM SUNDAY. ...WINTER STORM WARNING FOR MDZ001 FROM 9 PM SATURDAY TO NOON SUNDAY. OH...WIND ADVISORY FOR OHZ039-OHZ040-OHZ041-OHZ048-OHZ049-OHZ050- OHZ057-OHZ058-OHZ059-OHZ068-OHZ069 FROM 9 PM SATURDAY TO 7 PM SUNDAY. PA...WIND ADVISORY FOR PAZ007-PAZ008-PAZ009-PAZ013-PAZ014-PAZ015- PAZ016-PAZ020-PAZ021-PAZ022-PAZ023-PAZ029-PAZ030-PAZ031- PAZ032 FROM 9 PM SATURDAY TO 7 PM SUNDAY. ...WINTER WEATHER ADVISORY FOR PAZ007-PAZ008-PAZ009-PAZ015-PAZ016- PAZ023 FROM 9 PM SATURDAY TO NOON SUNDAY. ...WINTER WEATHER ADVISORY FOR PAZ014-PAZ022 FROM 9 PM SATURDAY TO 1 AM SUNDAY. ...WINTER STORM WARNING FOR PAZ030-PAZ032 FROM 9 PM SATURDAY TO NOON SUNDAY. WV...WIND ADVISORY FOR WVZ001-WVZ002-WVZ003-WVZ004-WVZ012-WVZ021- WVZ022-WVZ023-WVZ041 FROM 9 PM SATURDAY TO 7 PM SUNDAY. ...WINTER STORM WARNING FOR WVZ023-WVZ041 FROM 9 PM SATURDAY TO NOON SUNDAY. && $$ pa AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NASHVILLE TN 825 PM CST SAT APR 2 2005 .DISCUSSION... SKIES WERE MOSTLY CLEAR ACROSS MIDDLE TENNESSEE THIS EVENING, WITH TEMPERATURES SLIDING THROUGH THE 40S AT MOST LOCATIONS. STILL EXPECT SURFACE RIDGE TO BUILD ACROSS THE AREA OVERNIGHT AND BRING DECREASING WINDS AND MOSTLY CLEAR SKIES. LATEST RUC SUGGESTS WINDS MAY STAY IN THE 5 TO 10 MPH RANGE ALONG THE PLATEAU, WHILE DROPPING TO AROUND 5 MPH AT MOST OTHER SPOTS. WINDS WILL PROBABLY HELP PREVENT TEMPERATURES FROM BOTTOMING OUT AT THE DEWPOINT. CURRENT ZFP PROJECTION OF MID 30S FOR MINIMUM TEMEPRATURES OVER MOST OF MIDDLE TENNESSEE REMAINS REASONABLE, ALTHOUGH LATEST MODELS HAVE SHOWN A TREND TOWARD KEEPING THINGS A TAD WARMER (PROBABLY DUE TO OVERNIGHT MIXING IN THE BOUNDARY LAYER). NEVERTHELESS, BELIEVE COOP STATIONS WILL END UP A FEW DEGREES COOLER THAN WHAT IS REPRESENTED BY THE BNA MOS NUMBERS (AS THEY OFTEN ARE). THUS, HAVE LEFT MOST FIRST PERIOD TEMPERATURE EXPECTATIONS ALONE. .OHX WATCHES/WARNINGS/ADVISORIES... TN...NONE. && $$ 19 tn AREA FORECAST DISCUSSION...UPDATE NATIONAL WEATHER SERVICE WAKEFIELD VA 1230 PM EST SAT APR 2 2005 UPDATED TO REMOVE FLOOD WATCH HEADLINES AND REFRESH AFTERNOON WORDING. EVENT ENDING WEST TO EAST ACROSS CWA AS FRONT PROGRESSES SLOWLY TO THE COAST. ____________________________________________________________________ RADAR/SAT SHOWS BULK OF PRECIP AS WIDESPREAD SHOWERS AND SCATTERED TSTMS...LINE OF STRONGER INTENSITIES MOVING THROUGH CENTRAL PIEDMONT WITH RAINFALL RATES BETWEEN .25 AND .50 INCHES PER HOUR. WILL CONTINUE FLOOD WATCH TO EXPIRATION OF 20Z. TEMPS HOLDING IN THE 60S. FORECAST IN GOOD SHAPE ATTM. WINDS EXPECTED TO APPROACH ADVISORY CRITERIA TONIGHT INTO SUNDAY AS LOW TIGHTENS TO THE NORTH...SO WILL CONSIDER ISSUING WIND WARNING WITH NEXT PACKAGE. && .AVIATION... EXPECT IFR/LIFR CONDS FOR MOST OF THE AREA THRU ERLY AFTN...DUE TO SHRAS/POSSIBLE TSRAS WITH FRNT. VFR/MVFR LATER THIS AFTN AFTR FRNTL PASSAGE. && .MARINE... UPDATED TO INCREASE FORECASTED WIND SPEEDS THROUGHOUT...ALSO RAISED WAVE HEIGHTS ON CURRITUCK SOUND DUE TO FETCH IN DEEPER CHANNELS. INCRSNG S WNDS THIS MORNG IN ADVANCE OF LO PRES AND APPROACHING COLD FRNT. STRNG SCA CONDS BAY/SND...WITH GUSTS TO GALE CONDS ON CST. FRNT PUSHES OFF THE CST LATER THIS AFTN...BUT STRNG LO PRES TO THE N/NE WILL MAINTAIN SCA CONDS TNGT INTO SUN NGT. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...NONE. NC...NONE. VA...FLOOD WATCH FOR ZONES VAZ048-049-060>071-079-080. MARINE...GALE WARNING FOR ANZ650-652-654-656-658. SMALL CRAFT ADVISORY FOR ANZ630>633. && PREVIOUS AFD BELOW ________________________________________________________________ .SHORT TERM (TODAY)... LIKELY TO BE BUSY DAY COMING UP...CNVTN MVG THROUGH SE CONUS PAST 18-24 HRS HAS LMTD PCPN ACRS RGN. TRENDS OF CNVTN INVOF SE CST ON THE WANE ATTM...SUGGS THAT TRANSITION TO BETTER PCPN DVLPMNT FARTHER N AHD OF CDFNT CRSG MTNS THROUGH THE MORNING HRS. ALREADY...AT LEAST SCTD RW+ MVG N THROUGH CNTRL/NRN SXNS. SFC WMFNT MVG N INTO FA ATTM...AND WL BE AWAITING TRAILING CDFNT FM THE WSW BY THE MIDDAY/ERY AFTN HRS (WHICH REACHES THE CST LT). 06Z RUC SHOWING INCRSG LLVL INSTABILITY/SHR PTNTL AXIS AHD OF CDFNT. LIKELY WON'T BE WDSPRD SHIELD OF HVY RA...BUT ENUF CVRG TO KP FFA WHR SOIL CONDS MOST SATURATED (W OF I95). ADDTNLLY...MUCH OF FA IN SLGT RISK SVR...WL BE WATCHING FOR PTNTL SQLN DVLPMNT INVOF CDFNT REACHING AREA BY MID/LT MORNING AND PROGRESSING E. MAIN THREAT STRNG WNDS. W/ COLD CORE ALOFT ARRIVING FM W DURG AFTN/EVE...PSBL REDVLPMNT OF SHRAS/TSRAS (HAIL/GSTY WNDS??). LASTLY...PTNTL FOR MOD/STRNG GRAD S WNDS (ESP NR CST) TDA...SO GALES ON OCN...MENTIONING SPDS TO 35 MPH FM ERN SHR TO CSTL NE NC. && .LONG TERM (TONIGHT THROUGH THURSDAY)... LO PRES SLO TO DEPART TNGT/SUN. KPG PLNTY OF SC ACRS AREA...EVEN LO CHC POPS...ESP NRN HALF...INTO SUN AFTN. WNW WNDS RMNG MOD. DRIER WX AND AT LEAST SEASONABLE TEMPS MON THROUGH WED. && $$ 22 va AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WAKEFIELD VA 1000 AM EST FRI APR 1 2005 RADAR/SAT SHOWS BULK OF PRECIP AS WIDESPREAD SHOWERS AND SCATTERED TSTMS...LINE OF STRONGER INTENSITIES MOVING THROUGH CENTRAL PIEDMONT WITH RAINFALL RATES BETWEEN .25 AND .50 INCHES PER HOUR. WILL CONTINUE FLOOD WATCH TO EXPIRATION OF 20Z. TEMPS HOLDING IN THE 60S. FORECAST IN GOOD SHAPE ATTM. WINDS EXPECTED TO APPROACH ADVISORY CRITERIA TONIGHT INTO SUNDAY AS LOW TIGHTENS TO THE NORTH...SO WILL CONSIDER ISSUING WIND WARNING WITH NEXT PACKAGE. && .AVIATION... EXPECT IFR/LIFR CONDS FOR MOST OF THE AREA THRU ERLY AFTN...DUE TO SHRAS/POSSIBLE TSRAS WITH FRNT. VFR/MVFR LATER THIS AFTN AFTR FRNTL PASSAGE. && .MARINE... UPDATED TO INCREASE FORECASTED WIND SPEEDS THROUGHOUT...ALSO RAISED WAVE HEIGHTS ON CURRITUCK SOUND DUE TO FETCH IN DEEPER CHANNELS. INCRSNG S WNDS THIS MORNG IN ADVANCE OF LO PRES AND APPROACHING COLD FRNT. STRNG SCA CONDS BAY/SND...WITH GUSTS TO GALE CONDS ON CST. FRNT PUSHES OFF THE CST LATER THIS AFTN...BUT STRNG LO PRES TO THE N/NE WILL MAINTAIN SCA CONDS TNGT INTO SUN NGT. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...NONE. NC...NONE. VA...FLOOD WATCH FOR ZONES VAZ048-049-060>071-079-080. MARINE...GALE WARNING FOR ANZ650-652-654-656-658. SMALL CRAFT ADVISORY FOR ANZ630>633. && PREVIOUS AFD BELOW ________________________________________________________________ .SHORT TERM (TODAY)... LIKELY TO BE BUSY DAY COMING UP...CNVTN MVG THROUGH SE CONUS PAST 18-24 HRS HAS LMTD PCPN ACRS RGN. TRENDS OF CNVTN INVOF SE CST ON THE WANE ATTM...SUGGS THAT TRANSITION TO BETTER PCPN DVLPMNT FARTHER N AHD OF CDFNT CRSG MTNS THROUGH THE MORNING HRS. ALREADY...AT LEAST SCTD RW+ MVG N THROUGH CNTRL/NRN SXNS. SFC WMFNT MVG N INTO FA ATTM...AND WL BE AWAITING TRAILING CDFNT FM THE WSW BY THE MIDDAY/ERY AFTN HRS (WHICH REACHES THE CST LT). 06Z RUC SHOWING INCRSG LLVL INSTABILITY/SHR PTNTL AXIS AHD OF CDFNT. LIKELY WON'T BE WDSPRD SHIELD OF HVY RA...BUT ENUF CVRG TO KP FFA WHR SOIL CONDS MOST SATURATED (W OF I95). ADDTNLLY...MUCH OF FA IN SLGT RISK SVR...WL BE WATCHING FOR PTNTL SQLN DVLPMNT INVOF CDFNT REACHING AREA BY MID/LT MORNING AND PROGRESSING E. MAIN THREAT STRNG WNDS. W/ COLD CORE ALOFT ARRIVING FM W DURG AFTN/EVE...PSBL REDVLPMNT OF SHRAS/TSRAS (HAIL/GSTY WNDS??). LASTLY...PTNTL FOR MOD/STRNG GRAD S WNDS (ESP NR CST) TDA...SO GALES ON OCN...MENTIONING SPDS TO 35 MPH FM ERN SHR TO CSTL NE NC. && .LONG TERM (TONIGHT THROUGH THURSDAY)... LO PRES SLO TO DEPART TNGT/SUN. KPG PLNTY OF SC ACRS AREA...EVEN LO CHC POPS...ESP NRN HALF...INTO SUN AFTN. WNW WNDS RMNG MOD. DRIER WX AND AT LEAST SEASONABLE TEMPS MON THROUGH WED. && $$ 22 va AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE CHARLESTON WV 345 PM EST SAT APR 2 2005 .SHORT TERM (REST OF TONIGHT THROUGH SUNDAY)... UPPER LOW CONTINUES TO MOVE EAST ACROSS PORTIONS OF OHIO AND WEST VIRGINIA. BEST PRECIPITATION IS WEST OF THIS FEATURE AND THIS TREND SHOULD CONTINUE. PRECIPITATION ACROSS MOST OF THE AREA IS CURRENTLY IN THE FORM OF RAIN...WITH A MIXTURE ACROSS SOUTHEAST OHIO AND THE WEST VIRGINIA COUNTIES. AS AIRMASS COOLS...FEEL PRECIPITATION WILL MIX WITH AND CHANGE TO SNOW OVER MOST LOCATIONS BY MORNING. LATEST GUIDANCE CONTINUES TO INDICATE BEST QPF OVERNIGHT WILL BE ACROSS OUR NORTHERN COUNTIES. COMBINATION OF HIGHEST QPF AND COOLING TEMPERATURES SUGGEST THE BEST CHANCES FOR HEAVY SNOW WILL BE ACROSS THE NORTHERN MOUNTAIN COUNTIES WITH LESSOR AMOUNTS IN THE ADJACENT COUNTIES. HAVE DECIDED TO ISSUE WINTER STORM WARNING IN RANDOLPH AND POCAHONTAS COUNTIES FOR 4-7 INCHES OVERNIGHT. IN ADDITION...WINTER WEATHER ADVISORY HAS BEEN ISSUED FOR BARBOUR...UPSHUR...WEBSTER AND NICHOLAS COUNTIES FOR 2 -4 INCHES. LATEST SNOW GRIDS INDICATE UP TO 3 INCHES OF SNOW IN THE MOUNTAINS ACROSS FAYETTE AND RALEIGH COUNTIES...SO THOSE COUNTIES WILL ALSO HAVE TO BE MONITORED. PLAN ON MAINTAINING THE WIND ADVISORY AS LATEST GUIDANCE SHOWS GUSTY WINDS WILL DEVELOP TONIGHT INTO SUNDAY. WIND GUSTS WILL APPROACH ADVISORY CRITERIA ACROSS THE LOWER ELEVATIONS...WITH HIGHER GUSTS EXPECTED IN THE HIGHER ELEVATIONS. THE HIGHEST ELEVATIONS MAY SEE WIND GUSTS EXCEED 50 KNOTS...BUT ONLY THE HIGHEST ELEVATIONS SHOULD SEE THESE HIGH WINDS. PRECIPITATION SHOULD TAPER OFF FROM THE WEST ON SUNDAY AS THE SYSTEM MOVES AWAY. && .PREVIOUS DISCUSSION... (ISSUED 158 PM EST SAT APR 2 2005) LONG TERM (SUNDAY NIGHT THROUGH SATURDAY)... WINDS WILL BE ON THE DECREASE SUNDAY NIGHT...AS PRESSURE GRADIENT WEAKENS WITH NE MOVING LOW. STILL HAVE SOME HIGHER GUSTS AROUND 30-35 MPH EARLY...MAINLY ACROSS THE HIGHEST TERRAIN. KEEPING THE MID TERM OF THIS FORECAST DRY FOR NOW (SUNDAY NIGHT THROUGH TUESDAY NIGHT). MAIN CONCERN PRECIPITATION WISE WILL BE FOR TUESDAY NIGHT...AS WEAK WARM FRONT FROM NEXT SYSTEM PUSHES NORTHEASTWARD ACROSS THE CWA. WITH THIS WARM FRONT...WILL CONTINUE TO KEEP OVERNIGHT TEMPS WARMER THAN GUIDANCE TUESDAY NIGHT INTO WEDNESDAY. OVERALL...HIGH PRESSURE WITH UPPER LEVEL RIDGE WILL REMAIN IN CONTROL THROUGH TUESDAY NIGHT. IN THE LONG TERM...GUIDANCE CONSISTENT BRINGING WEATHER ASSOCIATED WITH LOW PRESSURE SYSTEM EXPECTED TO MOVE INTO THE OHIO VALLEY WEDNESDAY NIGHT. GFS SHOWS DEEP LOW PRESSURE VERTICALLY STACK, PRECIPITABLE WATER OF 1 INCH...NEAR ZERO LIFTED INDEX AND SOME CAPE LATE WEDNESDAY NIGHT. GFS KEEPS THE LOW PRESSURE NEARLY STATIONARY OVER WEST VIRGINIA FROM THURSDAY THROUGH SATURDAY. THIS SITUATION WILL KEEP ABUNDANT LOW LEVEL MOISTURE OVER THE AREA WHICH MAY PROLONG PRECIPITATION ACTIVITY. THE PRECIPITATION LOOKS LIKE WILL BE ALL RAIN PER H8 TEMPERATURES ABOVE FREEZING WEDNESDAY AND THURSDAY. THEN...A THERMAL TROUGH WITH H8 TEMPERATURES IN NEAR -4 DEGREES MOVES IN OVER THE AREA BRINGING COLD AND DRY AIR MASS. HPC FRONTS/PRESSURE PLOTS BRING THE LOW AND ITS ASSOCIATED FRONTS SLOWER ON THURSDAY MORNING FINALLY EXITING THE AREA BY FRIDAY MORNING...SIMILAR TO ECMWF. KEPT POPS AND WEATHER WITH THE SAME TIMING FROM THE PAST COUPLE OF DAYS WITH POSSIBLE THUNDERSTORMS....AND MAINTAIN DRY FRIDAY AND SATURDAY. TWEAKED TEMPERATURES UP PER MEX GUIDANCE BEEN HIGHER THAN PREVIOUS DAYS...ALTHOUGH WENT COOLER THAN MEX WED AND THU...AND SLIGHTLY WARMER OR CLOSE TO FRI AND SATURDAY. PREVIOUS DISCUSSION... (ISSUED 1245 PM EST SAT APR 2 2005) AVIATION... RADAR SHOWS PRECIPITATION OVER OHIO MOVING AROUND A LOW PRESSURE CENTER. THIS PRECIPITATION WILL REACH HTS AND CRW AROUND 19Z AS RAIN...THEN TURNING INTO A MIX OF RA/SN AROUND 21Z...AND THEN TO PROBABLY ALL SNOW AROUND 04Z. THESE CONDITIONS WILL SPREAD TO THE REST OF THE SITES DURING THE LATE NIGHT AND OVERNIGHT HOURS. THESE CONDITIONS WILL CONTINUE CREATING IFR CEILINGS. IFR/LIFR VISIBILITIES TOWARDS EARLY MORNING. SOUTHEAST FLOW WILL SHIFT NORTHWEST BY EARLY AFTERNOON AT HTS... SPREADING TO CRW...AND THEN TO PKB AND BKW LATER TONIGHT. WIND GUSTS FROM 25 TO 35 KNOTS WERE FORECASTED WITH THE SHOWERS. CONDITIONS WILL IMPROVE SUNDAY ALTHOUGH LOW CEILINGS MAY STILL PRESENT DURING THE MORNING HOURS. PREVIOUS DISCUSSION... (ISSUED 1052 AM EST SAT APR 2 2005) SHORT TERM (REST OF TODAY THROUGH TONIGHT)... CURRENT RADAR DATA AND WV IMAGERY SHOWS MID-LEVEL SHORTWAVE TROF IS LOCATED NEAR PERRY COUNTY OH...WITH A LARGE AREA OF RAIN/SNOW IN THE VICINITY OF THE TROF. OTHER PATCHES OF RAIN WERE MOVING NORTHEAST ACROSS THE FORECAST AREA. RUC MODEL SEEMS TO HAVE THE BEST HANDLE ON THE LOCATION OF THE TROF. THE TROF AND THE UPPER LOW WILL MOVE EAST ACROSS THE REGION THIS AFTERNOON...WITH THE NEST CHANCES OF PRECIPITATION BEING NEAR THESE FEATURES. HAVE BUMPED TEMPERATURES FOR THIS AFTERNOON DOWN A FEW DEGREES AS CLOUDS AND PRECIPITATION SHOULD KEEP TEMPERATURES FROM MOVING MUCH. CURRENT THINKING IS TO LET THE FLOOD WATCH EXPIRE AT NOON AS THERE HAVE NOT REALLY BEEN ANY WATER PROBLEMS. LATEST MODELS SUGGEST THERE MAY BE A SMALL THREAT OF SOME HEAVIER RAIN AMOUNTS ACROSS OUR NORTHERN WEST VIRGINIA EARLY TONIGHT. BUT THIS AREA DID NOT RECEIVE VERY HEAVY RAIN OVERNIGHT AND THERE WILL BE SEVERAL HOURS OF RELATIVELY DRY WEATHER BEFORE THE PRECIPITATION MOVES BACK IN. WILL JUST HAVE TO MONITOR THIS AREA THROUGH THE EVENING HOURS FOR POSSIBLE WATER PROBLEMS. WIND ADVISORY FOR TONIGHT STILL LOOKS TO BE ON TRACK AS THE ASSOCIATED SURFACE LOW DEEPENS AND MOVES SLOWLY EAST. WILL NOT MAKE ANY CHANGES TO WINTER STORM WATCH AT THIS TIME. BUT WILL TAKE A LOOK AT ALL OF THE MODELS AND MAKE A DECISION EARLY THIS AFTERNOON ON WHETHER A WARNING IS NEEDED. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...WIND ADVISORY FOR WVZ005>011-013>020-024>040-046-047 FROM 7 PM SATURDAY TO 4 PM SUNDAY. ...WINTER STORM WARNING FOR WVZ046-047 FROM 7 PM SATURDAY TO 11 AM SUNDAY. ...WINTER WEATHER ADVISORY FOR WVZ037>040 FROM 7 PM SATURDAY TO 11 AM SUNDAY. OH...WIND ADVISORY FOR OHZ066-067-075-076-083>087 FROM 7 PM SATURDAY TO 4 PM SUNDAY. KY...WIND ADVISORY FOR KYZ101>103-105 FROM 7 PM SATURDAY TO 4 PM SUNDAY. VA...WIND ADVISORY FOR VAZ003-004 FROM 7 PM SATURDAY TO 4 PM SUNDAY. && $$ SHORT TERM...JSH wv AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE CHARLESTON WV 158 PM EST SAT APR 2 2005 .LONG TERM (SUNDAY NIGHT THROUGH SATURDAY)... WINDS WILL BE ON THE DECREASE SUNDAY NIGHT...AS PRESSURE GRADIENT WEAKENS WITH NE MOVING LOW. STILL HAVE SOME HIGHER GUSTS AROUND 30-35 MPH EARLY...MAINLY ACROSS THE HIGHEST TERRAIN. KEEPING THE MID TERM OF THIS FORECAST DRY FOR NOW (SUNDAY NIGHT THROUGH TUESDAY NIGHT). MAIN CONCERN PRECIPITATION WISE WILL BE FOR TUESDAY NIGHT...AS WEAK WARM FRONT FROM NEXT SYSTEM PUSHES NORTHEASTWARD ACROSS THE CWA. WITH THIS WARM FRONT...WILL CONTINUE TO KEEP OVERNIGHT TEMPS WARMER THAN GUIDANCE TUESDAY NIGHT INTO WEDNESDAY. OVERALL...HIGH PRESSURE WITH UPPER LEVEL RIDGE WILL REMAIN IN CONTROL THROUGH TUESDAY NIGHT. IN THE LONG TERM...GUIDANCE CONSISTENT BRINGING WEATHER ASSOCIATED WITH LOW PRESSURE SYSTEM EXPECTED TO MOVE INTO THE OHIO VALLEY WEDNESDAY NIGHT. GFS SHOWS DEEP LOW PRESSURE VERTICALLY STACK, PRECIPITABLE WATER OF 1 INCH...NEAR ZERO LIFTED INDEX AND SOME CAPE LATE WEDNESDAY NIGHT. GFS KEEPS THE LOW PRESSURE NEARLY STATIONARY OVER WEST VIRGINIA FROM THURSDAY THROUGH SATURDAY. THIS SITUATION WILL KEEP ABUNDANT LOW LEVEL MOISTURE OVER THE AREA WHICH MAY PROLONG PRECIPITATION ACTIVITY. THE PRECIPITATION LOOKS LIKE WILL BE ALL RAIN PER H8 TEMPERATURES ABOVE FREEZING WEDNESDAY AND THURSDAY. THEN...A THERMAL TROUGH WITH H8 TEMPERATURES IN NEAR -4 DEGREES MOVES IN OVER THE AREA BRINGING COLD AND DRY AIR MASS. HPC FRONTS/PRESSURE PLOTS BRING THE LOW AND ITS ASSOCIATED FRONTS SLOWER ON THURSDAY MORNING FINALLY EXITING THE AREA BY FRIDAY MORNING...SIMILAR TO ECMWF. KEPT POPS AND WEATHER WITH THE SAME TIMING FROM THE PAST COUPLE OF DAYS WITH POSSIBLE THUNDERSTORMS....AND MAINTAIN DRY FRIDAY AND SATURDAY. TWEAKED TEMPERATURES UP PER MEX GUIDANCE BEEN HIGHER THAN PREVIOUS DAYS...ALTHOUGH WENT COOLER THAN MEX WED AND THU...AND SLIGHTLY WARMER OR CLOSE TO FRI AND SATURDAY. && .PREVIOUS DISCUSSION... (ISSUED 1245 PM EST SAT APR 2 2005) AVIATION... RADAR SHOWS PRECIPITATION OVER OHIO MOVING AROUND A LOW PRESSURE CENTER. THIS PRECIPITATION WILL REACH HTS AND CRW AROUND 19Z AS RAIN...THEN TURNING INTO A MIX OF RA/SN AROUND 21Z...AND THEN TO PROBABLY ALL SNOW AROUND 04Z. THESE CONDITIONS WILL SPREAD TO THE REST OF THE SITES DURING THE LATE NIGHT AND OVERNIGHT HOURS. THESE CONDITIONS WILL CONTINUE CREATING IFR CEILINGS. IFR/LIFR VISIBILITIES TOWARDS EARLY MORNING. SOUTHEAST FLOW WILL SHIFT NORTHWEST BY EARLY AFTERNOON AT HTS... SPREADING TO CRW...AND THEN TO PKB AND BKW LATER TONIGHT. WIND GUSTS FROM 25 TO 35 KNOTS WERE FORECASTED WITH THE SHOWERS. CONDITIONS WILL IMPROVE SUNDAY ALTHOUGH LOW CEILINGS MAY STILL PRESENT DURING THE MORNING HOURS. PREVIOUS DISCUSSION... (ISSUED 1052 AM EST SAT APR 2 2005) SHORT TERM (REST OF TODAY THROUGH TONIGHT)... CURRENT RADAR DATA AND WV IMAGERY SHOWS MID-LEVEL SHORTWAVE TROF IS LOCATED NEAR PERRY COUNTY OH...WITH A LARGE AREA OF RAIN/SNOW IN THE VICINITY OF THE TROF. OTHER PATCHES OF RAIN WERE MOVING NORTHEAST ACROSS THE FORECAST AREA. RUC MODEL SEEMS TO HAVE THE BEST HANDLE ON THE LOCATION OF THE TROF. THE TROF AND THE UPPER LOW WILL MOVE EAST ACROSS THE REGION THIS AFTERNOON...WITH THE NEST CHANCES OF PRECIPITATION BEING NEAR THESE FEATURES. HAVE BUMPED TEMPERATURES FOR THIS AFTERNOON DOWN A FEW DEGREES AS CLOUDS AND PRECIPITATION SHOULD KEEP TEMPERATURES FROM MOVING MUCH. CURRENT THINKING IS TO LET THE FLOOD WATCH EXPIRE AT NOON AS THERE HAVE NOT REALLY BEEN ANY WATER PROBLEMS. LATEST MODELS SUGGEST THERE MAY BE A SMALL THREAT OF SOME HEAVIER RAIN AMOUNTS ACROSS OUR NORTHERN WEST VIRGINIA EARLY TONIGHT. BUT THIS AREA DID NOT RECEIVE VERY HEAVY RAIN OVERNIGHT AND THERE WILL BE SEVERAL HOURS OF RELATIVELY DRY WEATHER BEFORE THE PRECIPITATION MOVES BACK IN. WILL JUST HAVE TO MONITOR THIS AREA THROUGH THE EVENING HOURS FOR POSSIBLE WATER PROBLEMS. WIND ADVISORY FOR TONIGHT STILL LOOKS TO BE ON TRACK AS THE ASSOCIATED SURFACE LOW DEEPENS AND MOVES SLOWLY EAST. WILL NOT MAKE ANY CHANGES TO WINTER STORM WATCH AT THIS TIME. BUT WILL TAKE A LOOK AT ALL OF THE MODELS AND MAKE A DECISION EARLY THIS AFTERNOON ON WHETHER A WARNING IS NEEDED. PREVIOUS DISCUSSION... (ISSUED 452 AM EST SAT APR 2 2005) LONG TERM (SUNDAY NIGHT THROUGH FRIDAY)... FIGURING ON SNOW COVER IN NE COUNTIES...SO LOWERED MIN TEMP FOR SUNDAY NIGHT WITH THE CLEARING. ALSO LOWERED MAX TEMP A BIT FOR MONDAY IN NE WV. WEAK WARM FRONTAL ZONE TRIES TO SET UP LATE MONDAY INTO TUESDAY. GFS HAS A BIT MORE MOISTURE THAN NAM. LEAVING DRY AT THIS TIME. TOO ACTIVE/BUSY SHORT RANGE TO REEVALUATE WED-FRI TIME FRAME. HYDROLOGY... RAINFALL TOTALS HAVE EXCEEDED AN INCH IN PARTS OF OH AND KY WITH HIGHEST AMOUNTS IN THE 1.25 TO 1.5 INCH RANGE. CALLS MADE TO COUNTIES WITH THE MOST RAINFALL HAVE YIELDED NO REPORTS OF FLOODING PROBLEMS ALTHOUGH THERE HAS BEEN PONDING ON ROADWAYS. THE HEAVIEST OF THE RAIN HAS PULLED OUT OF NORTHEASTERN KENTUCKY AND WAS SLOWLY PUSHING OUT OF WESTERN WEST VIRGINIA AND EASTERN OHIO. THIS RAIN WILL NEED MONITORED OVER THE NEXT SEVERAL HOURS. THE WRAP AROUND RAIN BACK IN CENTRAL OHIO WILL ALSO AFFECT THESE AREAS LATER THIS MORNING AND COULD STILL BE ENOUGH TO...TOGETHER WITH THE EARLIER RAINFALL...TRIGGER SOME WATER PROBLEMS. RIVERS HAVE BEGUN TO SHOW A RISE BUT REMAIN WELL BELOW FLOOD STAGE AND ARE FOLLOWING OUR FORECASTS REASONABLY CLOSELY. ANOTHER STRONG RISE IS FORECAST ON THE HOCKING. IT IS AGAIN FORECAST TO CREST CLOSE TO FLOOD STAGE SUNDAY MORNING. THIS WILL NEED CLOSELY MONITORED. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...WIND ADVISORY FOR WVZ005>011-013>020-024>040-046-047 FROM 7 PM SATURDAY TO 4 PM SUNDAY. ...WINTER STORM WATCH FOR WVZ038>040-046-047 FROM 7 PM SATURDAY TO NOON SUNDAY. OH...WIND ADVISORY FOR OHZ066-067-075-076-083>087 FROM 7 PM SATURDAY TO 4 PM SUNDAY. KY...WIND ADVISORY FOR KYZ101>103-105 FROM 7 PM SATURDAY TO 4 PM SUNDAY. VA...WIND ADVISORY FOR VAZ003-004 FROM 7 PM SATURDAY TO 4 PM SUNDAY. && $$ LONG TERM...KF/ARJ wv AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE CHARLESTON WV 1245 PM EST SAT APR 2 2005 .AVIATION... RADAR SHOWS PRECIPITATION OVER OHIO MOVING AROUND A LOW PRESSURE CENTER. THIS PRECIPITATION WILL REACH HTS AND CRW AROUND 19Z AS RAIN...THEN TURNING INTO A MIX OF RA/SN AROUND 21Z...AND THEN TO PROBABLY ALL SNOW AROUND 04Z. THESE CONDITIONS WILL SPREAD TO THE REST OF THE SITES DURING THE LATE NIGHT AND OVERNIGHT HOURS. THESE CONDITIONS WILL CONTINUE CREATING IFR CEILINGS. IFR/LIFR VISIBILITIES TOWARDS EARLY MORNING. SOUTHEAST FLOW WILL SHIFT NORTHWEST BY EARLY AFTERNOON AT HTS... SPREADING TO CRW...AND THEN TO PKB AND BKW LATER TONIGHT. WIND GUSTS FROM 25 TO 35 KNOTS WERE FORECASTED WITH THE SHOWERS. CONDITIONS WILL IMPROVE SUNDAY ALTHOUGH LOW CEILINGS MAY STILL PRESENT DURING THE MORNING HOURS. && .PREVIOUS DISCUSSION... (ISSUED 1052 AM EST SAT APR 2 2005) SHORT TERM (REST OF TODAY THROUGH TONIGHT)... CURRENT RADAR DATA AND WV IMAGERY SHOWS MID-LEVEL SHORTWAVE TROF IS LOCATED NEAR PERRY COUNTY OH...WITH A LARGE AREA OF RAIN/SNOW IN THE VICINITY OF THE TROF. OTHER PATCHES OF RAIN WERE MOVING NORTHEAST ACROSS THE FORECAST AREA. RUC MODEL SEEMS TO HAVE THE BEST HANDLE ON THE LOCATION OF THE TROF. THE TROF AND THE UPPER LOW WILL MOVE EAST ACROSS THE REGION THIS AFTERNOON...WITH THE NEST CHANCES OF PRECIPITATION BEING NEAR THESE FEATURES. HAVE BUMPED TEMPERATURES FOR THIS AFTERNOON DOWN A FEW DEGREES AS CLOUDS AND PRECIPITATION SHOULD KEEP TEMPERATURES FROM MOVING MUCH. CURRENT THINKING IS TO LET THE FLOOD WATCH EXPIRE AT NOON AS THERE HAVE NOT REALLY BEEN ANY WATER PROBLEMS. LATEST MODELS SUGGEST THERE MAY BE A SMALL THREAT OF SOME HEAVIER RAIN AMOUNTS ACROSS OUR NORTHERN WEST VIRGINIA EARLY TONIGHT. BUT THIS AREA DID NOT RECEIVE VERY HEAVY RAIN OVERNIGHT AND THERE WILL BE SEVERAL HOURS OF RELATIVELY DRY WEATHER BEFORE THE PRECIPITATION MOVES BACK IN. WILL JUST HAVE TO MONITOR THIS AREA THROUGH THE EVENING HOURS FOR POSSIBLE WATER PROBLEMS. WIND ADVISORY FOR TONIGHT STILL LOOKS TO BE ON TRACK AS THE ASSOCIATED SURFACE LOW DEEPENS AND MOVES SLOWLY EAST. WILL NOT MAKE ANY CHANGES TO WINTER STORM WATCH AT THIS TIME. BUT WILL TAKE A LOOK AT ALL OF THE MODELS AND MAKE A DECISION EARLY THIS AFTERNOON ON WHETHER A WARNING IS NEEDED. PREVIOUS DISCUSSION... (ISSUED 630 AM EST SAT APR 2 2005) AVIATION (12Z TO 12Z)... WILL FORECAST TRENDS A FEW HOURS FASTER THAN EVEN THE 06Z NAM SUGGESTS. WIND SHIFT TO SW UNDER THE DEEPENING SFC LOW WAS FASTER MOVING E ACROSS WV BETWEEN 07-11Z. LULL MOVING INTO HTS-CRW-BKW REGION FOR 12-16Z..LIFTG TOWARD CKB-EKN 15-18Z. WRAP AROUND MOISTURE AND LOWERING FREEZING LEVEL MOVING QUICKLY INTO HTS-CRW-BKW ON S 15-21Z...THEN LIFTG N 18Z-00Z. WAS FASTER IN MIXING SOME FLAKES TO SURFACE. CEILINGS AND VISIBILITY IMPROVING HTS-CRW-BKW FM 06-12Z BUT LINGERING SNOW SHOWERS CKB-EKN THRU 12Z SUNDAY. STRONG LOW LEVEL WIND FLOW THRU PD. PREVIOUS DISCUSSION... (ISSUED 452 AM EST SAT APR 2 2005) LONG TERM (SUNDAY NIGHT THROUGH FRIDAY)... FIGURING ON SNOW COVER IN NE COUNTIES...SO LOWERED MIN TEMP FOR SUNDAY NIGHT WITH THE CLEARING. ALSO LOWERED MAX TEMP A BIT FOR MONDAY IN NE WV. WEAK WARM FRONTAL ZONE TRIES TO SET UP LATE MONDAY INTO TUESDAY. GFS HAS A BIT MORE MOISTURE THAN NAM. LEAVING DRY AT THIS TIME. TOO ACTIVE/BUSY SHORT RANGE TO REEVALUATE WED-FRI TIME FRAME. HYDROLOGY... RAINFALL TOTALS HAVE EXCEEDED AN INCH IN PARTS OF OH AND KY WITH HIGHEST AMOUNTS IN THE 1.25 TO 1.5 INCH RANGE. CALLS MADE TO COUNTIES WITH THE MOST RAINFALL HAVE YIELDED NO REPORTS OF FLOODING PROBLEMS ALTHOUGH THERE HAS BEEN PONDING ON ROADWAYS. THE HEAVIEST OF THE RAIN HAS PULLED OUT OF NORTHEASTERN KENTUCKY AND WAS SLOWLY PUSHING OUT OF WESTERN WEST VIRGINIA AND EASTERN OHIO. THIS RAIN WILL NEED MONITORED OVER THE NEXT SEVERAL HOURS. THE WRAP AROUND RAIN BACK IN CENTRAL OHIO WILL ALSO AFFECT THESE AREAS LATER THIS MORNING AND COULD STILL BE ENOUGH TO...TOGETHER WITH THE EARLIER RAINFALL...TRIGGER SOME WATER PROBLEMS. RIVERS HAVE BEGUN TO SHOW A RISE BUT REMAIN WELL BELOW FLOOD STAGE AND ARE FOLLOWING OUR FORECASTS REASONABLY CLOSELY. ANOTHER STRONG RISE IS FORECAST ON THE HOCKING. IT IS AGAIN FORECAST TO CREST CLOSE TO FLOOD STAGE SUNDAY MORNING. THIS WILL NEED CLOSELY MONITORED. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...WIND ADVISORY FOR WVZ005>011-013>020-024>040-046-047 FROM 7 PM SATURDAY TO 4 PM SUNDAY. ...WINTER STORM WATCH FOR WVZ038>040-046-047 FROM 7 PM SATURDAY TO NOON SUNDAY. OH...WIND ADVISORY FOR OHZ066-067-075-076-083>087 FROM 7 PM SATURDAY TO 4 PM SUNDAY. KY...WIND ADVISORY FOR KYZ101>103-105 FROM 7 PM SATURDAY TO 4 PM SUNDAY. VA...WIND ADVISORY FOR VAZ003-004 FROM 7 PM SATURDAY TO 4 PM SUNDAY. && $$ AVIATION...ARJ wv AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE CHARLESTON WV 1052 AM EST SAT APR 2 2005 .SHORT TERM (REST OF TODAY THROUGH TONIGHT)... CURRENT RADAR DATA AND WV IMAGERY SHOWS MID-LEVEL SHORTWAVE TROF IS LOCATED NEAR PERRY COUNTY OH...WITH A LARGE AREA OF RAIN/SNOW IN THE VICINITY OF THE TROF. OTHER PATCHES OF RAIN WERE MOVING NORTHEAST ACROSS THE FORECAST AREA. RUC MODEL SEEMS TO HAVE THE BEST HANDLE ON THE LOCATION OF THE TROF. THE TROF AND THE UPPER LOW WILL MOVE EAST ACROSS THE REGION THIS AFTERNOON...WITH THE NEST CHANCES OF PRECIPITATION BEING NEAR THESE FEATURES. HAVE BUMPED TEMPERATURES FOR THIS AFTERNOON DOWN A FEW DEGREES AS CLOUDS AND PRECIPITATION SHOULD KEEP TEMPERATURES FROM MOVING MUCH. CURRENT THINKING IS TO LET THE FLOOD WATCH EXPIRE AT NOON AS THERE HAVE NOT REALLY BEEN ANY WATER PROBLEMS. LATEST MODELS SUGGEST THERE MAY BE A SMALL THREAT OF SOME HEAVIER RAIN AMOUNTS ACROSS OUR NORTHERN WEST VIRGINIA EARLY TONIGHT. BUT THIS AREA DID NOT RECEIVE VERY HEAVY RAIN OVERNIGHT AND THERE WILL BE SEVERAL HOURS OF RELATIVELY DRY WEATHER BEFORE THE PRECIPITATION MOVES BACK IN. WILL JUST HAVE TO MONITOR THIS AREA THROUGH THE EVENING HOURS FOR POSSIBLE WATER PROBLEMS. WIND ADVISORY FOR TONIGHT STILL LOOKS TO BE ON TRACK AS THE ASSOCIATED SURFACE LOW DEEPENS AND MOVES SLOWLY EAST. WILL NOT MAKE ANY CHANGES TO WINTER STORM WATCH AT THIS TIME. BUT WILL TAKE A LOOK AT ALL OF THE MODELS AND MAKE A DECISION EARLY THIS AFTERNOON ON WHETHER A WARNING IS NEEDED. && .PREVIOUS DISCUSSION... (ISSUED 630 AM EST SAT APR 2 2005) AVIATION (12Z TO 12Z)... WILL FORECAST TRENDS A FEW HOURS FASTER THAN EVEN THE 06Z NAM SUGGESTS. WIND SHIFT TO SW UNDER THE DEEPENING SFC LOW WAS FASTER MOVING E ACROSS WV BETWEEN 07-11Z. LULL MOVING INTO HTS-CRW-BKW REGION FOR 12-16Z..LIFTG TOWARD CKB-EKN 15-18Z. WRAP AROUND MOISTURE AND LOWERING FREEZING LEVEL MOVING QUICKLY INTO HTS-CRW-BKW ON S 15-21Z...THEN LIFTG N 18Z-00Z. WAS FASTER IN MIXING SOME FLAKES TO SURFACE. CEILINGS AND VISIBILITY IMPROVING HTS-CRW-BKW FM 06-12Z BUT LINGERING SNOW SHOWERS CKB-EKN THRU 12Z SUNDAY. STRONG LOW LEVEL WIND FLOW THRU PD. PREVIOUS DISCUSSION... (ISSUED 452 AM EST SAT APR 2 2005) SHORT TERM (TODAY THROUGH SUNDAY)... LOW CURRENTLY OVER WEST VIRGINIA EXPECTED TO RAPIDLY INTENSIFY AS IT MEANDERS NORTHEASTWARD OVER THE NEXT 24 TO 36 HOURS. EXPECTED LULL IN PRECIPITATION WILL OCCUR THIS MORNING BEFORE WRAPAROUND ARRIVES THIS AFTERNOON. ELECTED TO KEEP FLOOD WATCH GOING. IT MAY NEED TO BE EXTENDED DEPENDING ON AFTERNOON QPF...PLUS THERE MAY BE ONE OR TWO RIVER FLOODING ISSUES TO DEAL WITH. BRING POPS BACK TO CATEGORICAL EVERYWHERE LATE THIS AFTERNOON AND TONIGHT WITH STRONG DEFORMATION ZONE BEHIND LOW. VERY IMPRESSIVE H500-H700 QVEC CONVERGENCE PROVIDING SUPPORT FOR A GREAT DEAL OF UVV...PARTICULARLY OVER THE NORTH CENTRAL AND NORTHEAST CWA. H850 TEMPS INITIALLY NOT TOO IMPRESSIVE...BUT DYNAMIC COOLING WILL ALLOW THEM TO SLIP DOWN TO -5/-6 OVERNIGHT. EXPECT MOST LOCATIONS TO SEE AT LEAST A BIT OF SNOW...BUT WARM GROUND AND BOUNDARY LAYER WILL KEEP ACCUMULATIONS DOWN FOR MANY. EXCEPTION WILL BE IN THE NORTHERN MOUNTAIN COUNTIES...WHERE HIGHER ELEVATIONS WILL BE COLD ENOUGH...PLUS HAVE THE DYNAMIC SUPPORT...TO SUPPORT HEAVY SNOW. ISSUED WINTER STORM WATCH FOR THIS AREA FOR A GENERAL 4-8 INCH ACCUMULATION THROUGH NOON SUNDAY. MAY EVENTUALLY NEED A SNOW ADVISORY FOR OTHER LOCATIONS SUCH AS CKB AND BKW...BUT STILL ENOUGH UNCERTAINTY HERE TO HOLD OFF FOR NOW. OTHER ISSUE IS WINDS...AS H850 WINDS OF 50-60 KTS WRAP IN TONIGHT AND CONTINUE THROUGH MUCH OF SUNDAY. SEE NO REASON TO NOT ISSUE WIND ADVISORY FOR THE ENTIRE CWA AS WIND GUSTS OF 45-50 MPH ARE LIKELY IN MANY LOCATIONS. COMBINATION OF SNOW/WIND COULD CAUSE NEAR BLIZZARD CONDITIONS ABOVE 3000 FEET LATE TONIGHT/EARLY SUNDAY...ALREADY MENTIONED IN WSW. PRECIP PATTERN TRANSITIONS TO MORE OF AN UPSLOPE CONFIGURATION AFTER 00Z AS DYNAMIC SUPPORT WANES. ALLOW POPS TO SLOWLY DECREASE THEREAFTER AS MOISTURE DECREASES...FINALLY ENDING IT BY 00Z MON. RAIN MIXES BACK IN SUNDAY...EVEN IN MOST OF THE WATCH AREA...THUS THE WATCH ENDS AT NOON. WINDS BEGIN TO DIMINISH AS WELL SUNDAY AFTERNOON WITH LOW PULLING INTO NEW YORK STATE. TEMPERATURES TRICKY TODAY WITH SW VA FIRST TO SEE THE COLDER AIR. MET WAS A USEFUL HOURLY T TEMPLATE. TRIED NOT TO STRAY TOO FAR FROM MOS THEREAFTER. LONG TERM (SUNDAY NIGHT THROUGH FRIDAY)... FIGURING ON SNOW COVER IN NE COUNTIES...SO LOWERED MIN TEMP FOR SUNDAY NIGHT WITH THE CLEARING. ALSO LOWERED MAX TEMP A BIT FOR MONDAY IN NE WV. WEAK WARM FRONTAL ZONE TRIES TO SET UP LATE MONDAY INTO TUESDAY. GFS HAS A BIT MORE MOISTURE THAN NAM. LEAVING DRY AT THIS TIME. TOO ACTIVE/BUSY SHORT RANGE TO REEVALUATE WED-FRI TIME FRAME. HYDROLOGY... RAINFALL TOTALS HAVE EXCEEDED AN INCH IN PARTS OF OH AND KY WITH HIGHEST AMOUNTS IN THE 1.25 TO 1.5 INCH RANGE. CALLS MADE TO COUNTIES WITH THE MOST RAINFALL HAVE YIELDED NO REPORTS OF FLOODING PROBLEMS ALTHOUGH THERE HAS BEEN PONDING ON ROADWAYS. THE HEAVIEST OF THE RAIN HAS PULLED OUT OF NORTHEASTERN KENTUCKY AND WAS SLOWLY PUSHING OUT OF WESTERN WEST VIRGINIA AND EASTERN OHIO. THIS RAIN WILL NEED MONITORED OVER THE NEXT SEVERAL HOURS. THE WRAP AROUND RAIN BACK IN CENTRAL OHIO WILL ALSO AFFECT THESE AREAS LATER THIS MORNING AND COULD STILL BE ENOUGH TO...TOGETHER WITH THE EARLIER RAINFALL...TRIGGER SOME WATER PROBLEMS. RIVERS HAVE BEGUN TO SHOW A RISE BUT REMAIN WELL BELOW FLOOD STAGE AND ARE FOLLOWING OUR FORECASTS REASONABLY CLOSELY. ANOTHER STRONG RISE IS FORECAST ON THE HOCKING. IT IS AGAIN FORECAST TO CREST CLOSE TO FLOOD STAGE SUNDAY MORNING. THIS WILL NEED CLOSELY MONITORED. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...FLOOD WATCH FOR WVZ005>011-013-014-016>019-046-047 FROM 8 PM FRIDAY TO NOON SATURDAY. ...WIND ADVISORY FOR WVZ005>011-013>020-024>040-046-047 FROM 7 PM SATURDAY TO 4 PM SUNDAY. ...WINTER STORM WATCH FOR WVZ038>040-046-047 FROM 7 PM SATURDAY TO NOON SUNDAY. OH...FLOOD WATCH FOR OHZ066-067-075-076-083>087 FROM 8 PM FRIDAY TO NOON SATURDAY. ...WIND ADVISORY FOR OHZ066-067-075-076-083>087 FROM 7 PM SATURDAY TO 4 PM SUNDAY. KY...FLOOD WATCH FOR KYZ101>103-105 FROM 8 PM FRIDAY TO NOON SATURDAY. ...WIND ADVISORY FOR KYZ101>103-105 FROM 7 PM SATURDAY TO 4 PM SUNDAY. VA...WIND ADVISORY FOR VAZ003-004 FROM 7 PM SATURDAY TO 4 PM SUNDAY. && $$ SHORT TERM...JSH wv AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE PADUCAH KY 308 AM CDT SUN APR 3 2005 .DISCUSSION... A WARMING TREND WILL BEGIN TODAY AS A SURFACE HIGH PRESSURE RIDGE MOVES EAST OF THE FORECAST AREA. 06Z RUC ANALYSIS SHOWS FAIRLY STRONG WARM ADVECTION IS ALREADY UNDERWAY AT 850 MB...WHERE THE FLOW IS WESTERLY ALONG THE RIDGE AXIS. STRONG SOLAR HEATING AND INCREASING LOW LEVEL SOUTHWEST FLOW WILL RESULT IN A LARGE TEMP RISE...ABOUT 35 DEGREES FROM THE MORNING LOW. THE ONLY CLOUDINESS TO CONTEND WITH WILL BE A LITTLE MID AND UPPER LEVEL CLOUDINESS ASSOCIATED WITH A 500 MB SHORTWAVE OVER THE CENTRAL PLAINS AT 06Z. THE NAM/GFS TAKE THIS SHORTWAVE SOUTHEAST ACROSS THE LOWER OHIO VALLEY AROUND 18Z. GFS/NGM MOS HIGHS ARE SIMILAR AND WILL BE FOLLOWED. BRISK SOUTHWEST BOUNDARY LAYER FLOW TONIGHT WILL KEEP TEMPERATURES UP. SOME OF THE NORMALLY COOLER LOW LYING AREAS MAY DECOUPLE TONIGHT...ALLOWING LOCALLY MUCH COOLER READINGS. GFS/NGM MOS LOWS ARE SIMILAR AND WILL BE FOLLOWED. MID AND UPPER LEVEL RIDGING WILL KEEP MOST CLOUDINESS AT BAY THROUGH THE NIGHT. CONTINUED STRONG WARM ADVECTION ON MONDAY WILL RESULT IN HIGHS IN THE 70S THROUGHOUT THE FORECAST AREA. IT WILL ALSO BE RATHER BREEZY IN WESTERN COUNTIES...WHICH COULD CAUSE SOME FIRE WEATHER CONCERNS. MANY COUNTIES IN SE MISSOURI ESCAPED SIGNIFICANT RAINFALL WITH THE LAST WEATHER SYSTEM...LEAVING FUEL MOISTURE ON THE LOW SIDE. SOME PERIODS OF MID AND HIGH CLOUDINESS MAY ACCOMPANY A WEAK 500 MB SHORTWAVE MOVING THROUGH THE FLATTENING RIDGE...BUT NOT ENOUGH TO SIGNIFICANTLY AFFECT HIGHS. SLOW MOISTENING OF THE COLUMN WILL OCCUR MONDAY NIGHT THROUGH TUESDAY AS THE FLOW AT ALL LEVELS BECOMES MORE SOUTHERLY. GFS/NAM ARE IN PRETTY GOOD AGREEMENT WITH EACH OTHER ON A 500 MB CLOSED LOW MOVING NORTHEAST ACROSS THE CENTRAL PLAINS TUESDAY NIGHT AND WEDNESDAY. THIS IS MUCH FURTHER NORTH THAN RUNS SHOWED 24 HOURS AGO...AND IT CONFLICTS WITH 12Z ECMWF GUIDANCE. IF THIS VERIFIES AND THE ASSOCIATED SURFACE LOW PASSES WELL TO OUR NORTH...THE POTENTIAL FOR WIDESPREAD CONVECTION WILL BE HIGHER. BOTH GFS/NAM SHOW A 50 TO 60 KNOT 850 MB JET SHIFTING EAST ACROSS THE MID MISSISSIPPI VALLEY TUESDAY NIGHT. PLENTY OF MOISTURE WILL BE AVAILABLE FOR A BAND OF CONVECTION ALONG THE EASTWARD MOVING OCCLUDED FRONT. THE LATEST GFS MODEL STRONGLY DRIES OUT THE LOW LEVELS IN THE WAKE OF THE OCCLUDED FRONT ON WEDNESDAY. THIS COULD RESULT IN PERIODS OF SUNSHINE ON WEDNESDAY. HOWEVER...WITH VERY COLD TEMPS ALOFT ASSOCIATED WITH THE 500 MB LOW...PERIODS OF SUNSHINE WOULD RESULT IN DIURNAL INSTABILITY SHOWERS AND STORMS. REGARDING THE TRACK OF THE 500 MB LOW AFTER WEDNESDAY...THE MODELS VARY WIDELY. PREFER THE GFS TRACK...WHICH TAKES IT BACK SOUTHEAST ACROSS THE LOWER OHIO VALLEY THURSDAY AS IT PHASES WITH THE NORTHERN STREAM. 12Z ECMWF SHOWS THIS PHASING THE BEST. THIS WILL KEEP SOME PRECIPITATION LINGERING THROUGH THURSDAY...ALONG WITH COOLER TEMPS. MOST OF THE MEDIUM RANGE GUIDANCE SHOWS 500 MB RIDGING THEN MOVING INTO THE FORECAST AREA FRIDAY AND SATURDAY...BRINGING A RETURN TO WARMER AND DRIER CONDITIONS. && .PAH WATCHES/WARNINGS/ADVISORIES... .KY...NONE .MO...NONE .IL...NONE .IN...NONE && $$ MY ky AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 1204 AM EST SUN APR 3 2005 .AVIATION... WEATHER WILL BE RATHER BENIGN THROUGH THE 24 HOUR TAF PERIOD. DRY AIR MASS AND SUBSIDENCE WILL PREVAIL WITH LOWEST CLOUDS EXPECTED AROUND 15K FEET INTO THE EARLY MORNING HOURS AT DTW AND DET ON BACK SIDE OF EASTERN SYSTEM...SCATTERED HIGH CLOUDS FNT/MBS. THEN CLEAR SKIES SUNDAY AND SUNDAY EVENING. NO VISIBILITY RESTRICTIONS OF ANY KIND. GUSTS WILL CONTINUE TO SUBSIDE OVERNIGHT DET/DTW...THEN FLARE BACK UP INTO 25 TO 30 KNOT RANGE ALL TAF SITES BY MID DAY SUNDAY AS DIURNAL INCREASE IN MIXING LAYER ALLOWS TAPPING THE HIGHER WINDS ALOFT AGAIN. && .UPDATE...ISSUED 740 PM EST SAT LOOKING AT RADAR TRENDS FROM DTX 88D AND CANADIAN EXETER RADAR...IT APPEARS UNLIKELY THAT THE PRECIPITATION SHIELD WHICH HAS RETREATED EAST WILL BULGE BACK WEST INTO FORECAST AREA. THUS...A DRY REST OF TONIGHT THROUGHOUT. HAVE TWEAKED SKY GRIDS FOR CURRENT CLEARING TRENDS AND LOWERED LAND WINDS SOMEWHAT TONIGHT AS WELL...AS CLEAR SKIES ALREADY SEEN DECOUPLING THE FLOW AND THUS LOWERING REPORTED WINDS. ZONE FORECAST PACKAGE WILL BE UPDATED SHORTLY. && .SHORT TERM...TONIGHT AND SUNDAY...ISSUED 355 PM EST SAT 12Z RAOBS/WATER VAPOR LOOP SHOW AN UPPER LOW MOVING THROUGH THE TENNESSEE/OHIO VALLEYS...WITH THE SURFACE LOW REDEVELOPING ALONG THE MID ATLANTIC COAST. REGIONAL RADARS SHOW PERSISTENT PRECIP BAND ACROSS SOUTHEASTERN ONTARIO...STILL BRUSHING THE FAR SOUTHEAST CWA. VIS SATELLITE SHOWS CLEARING UPSTREAM...WITH ONLY THINNING HIGH CLOUDS ACROSS THE SAGINAW VALLEY. MAIN FOCUS FOR THE FIRST 24 HOURS WILL BE WITH INITIAL PRECIP. 18Z RUC IS A BIT SLOWER THAN THE 12Z/15Z RUNS TAKING THE BEST MID-LEVEL DEFORMATION THROUGH THE CWA...AND CONSEQUENTLY HOLD ON TO LIFT ACROSS THE FAR SOUTHEAST CWA FOR LONGER. REGIONAL RADARS HAVE SHOWN A SLIGHT REORIENTATION WITH BETTER LIFT DEVELOPING FARTHER NORTH ACROSS ONTARIO AS THE VORT CENTER SWINGS BACK AROUND THE CUTOFF LOW. WILL HOLD ON TO CATEGORICAL POPS INTO THE EARLY EVENING ACROSS THE VERY FAR SOUTHEAST CWA...MAINLY MACOMB/ST CLAIR BASED ON RECENT RADAR TRENDS. AS FAR A PRECIP TYPE...RECENT TAMDAR SOUNDINGS CONTINUE TO SHOW FREEZING LEVELS GENERALLY 1.6-18.KFT ACROSS THE SOUTHEAST CWA. THERE HAVE BEEN MORE SNOW REPORTS...ESPECIALLY FROM THE PHN/YZR AREA...CORRESPONDING WITH STRONGER RADAR RETURNS/HEAVIER PRECIP RATES. WILL ALLOW FOR MORE SNOW ACROSS ST CLAIR COUNTY...AND KEEP IT JUST A CHANCE OF SNOW MIXED IN ACROSS MACOMB. 1000-850MB TRAJECTORIES SUPPORT A SLOWER CLEARING TREND...AT LEAST ACROSS THE EASTERN CWA. WITH CLOUD SHIELD ALREADY PRETTY THIN ACROSS THE NORTHWEST...SHOULD SEE CLEARING PRETTY EARLY IN THE TRI CITIES. ACTUALLY WILL START MIDLAND/BAY AS MOSTLY CLEAR. DEEPER MOISTURE WILL CONTINUE TO PULL EAST AS THE SYSTEM MOVE TO EASTERN PENNSYLVANIA TONIGHT AND FURTHER WRAPS UP...ALLOWING THE CLEARING SKIES TO WORK THROUGH THE CWA. GRADIENT STAYS PRETTY STRONG THROUGH SUNDAY...WITH A PRETTY WELL MIXED BOUNDARY LAYER THROUGH THE NIGHT LEADING TO SOME CONTINUED GUSTINESS. NOT MUCH OF A TEMPERATURE GRADIENT ACROSS THE STATE WITH LITTLE THERMAL ADVECTION BEHIND THIS SYSTEM...BUT WILL KEEP LOWS A COUPLE DEGREES COLDER ACROSS THE SAGINAW VALLEY WITH EARLIER CLEARING. THERE SHOULD BE A GOOD DEAL OF SUNSHINE ON SUNDAY. HOWEVER...BOTH NAM/GFS TRY TO BRING IN THE MID-LEVEL DECK FROM MINNESOTA. UPPER FLOW BECOMES MORE CONFLUENT ACROSS THE STATE BETWEEN SHORTWAVE RIDGE OVER THE WESTERN GREAT LAKES AND LOW OVER THE NORTHEAST. THIS MID/UPPER LEVEL MOISTURE MAY HAVE A DIFFICULT TIME MAKING IT THIS FAR EAST...BUT THERE SHOULD BE ENOUGH CLOUDS AROUND FOR MOSTLY SUNNY AS OPPOSED TO PLAIN SUNNY SKIES. FORECAST SOUNDINGS SHOW US MIXING UP TO 850MB...WHERE TEMPERATURES HOVER FROM -2C TO 0C. WITH GOOD APRIL INSOLATION...THIS SHOULD HELP US CLIMB BACK INTO THE 50S. && .LONG TERM...MONDAY THROUGH SATURDAY...ISSUED 355 PM EST SAT INITIAL PROBLEMS IN THE LONG TERM WILL BE JUST HOW MILD TO GO WITH TEMPERATURES AS CURRENT SYSTEM WORKS SLOWLY OFF TO THE NORTHEAST & WEST/NORTHWEST FLOW SETS IN BEHIND IT. THEREAFTER...SOUTHERLY FLOW GRADUALLY SETS UP AS NEXT WEATHER MAKER DIGS INTO THE OHIO VALLEY BY WEDNESDAY AND THURSDAY. MODELS ALL SHOW A VERY VIGOROUS UPPER LOW DEVELOPING IN THE AREA BY MID/LATE WEEK...BUT DIFFER RATHER SIGNIFICANTLY WITH EACH OTHER AND FROM RUN TO RUN. TREND...HOWEVER...SUGGESTS THAT AN EXTENDED PERIOD OF RAIN IS ON TAP DURING THE EXTENDED FORECAST...OR AT THE VERY LEAST...A 2 OR 3 DAY PERIOD IN WHICH VARIOUS "WAVES" OF RAIN AND EMBEDDED THUNDER...WILL ROTATE THROUGH THE AREA. IN TERMS OF TEMPERATURES...WILL MAKE SOME ADJUSTMENTS TO LAKESHORE TEMPERATURES ON DAYS IN WHICH AN ONSHORE FLOW SEEMS MORE LIKELY. NAMELY ON MONDAY AS LIGHT...NORTHWEST FLOW SHOULD BE DOMINATED BY LAKE BREEZE BY AFTERNOON. THEN...AS AFOREMENTIONED SYSTEM WRAPS UP TO OUR SOUTHWEST...OVERALL SYNOPTIC FLOW WILL TEND TO A SOLID SOUTHEASTERLY DIRECTION. HENCE...WARMEST IN THE WEST CENTRAL CWA AND COLDEST OFF LAKE ERIE/LAKE HURON. TREND WILL BE FOR MILD WEATHER INTO THE WEDNESDAY AND PERHAPS THURSDAY TIMEFRAME...DEPENDING ON JUST HOW/WHERE THIS UPPER LOW PRESSURE SYSTEM EVOLVES. THEREAFTER...EXPECT A COOL DOWN FOR THE UPCOMING WEEKEND AS CORE OF SYSTEM (AND ASSOCIATED COLDER AIR) DRIFTS THROUGH OR VERY NEAR THE AREA...AND COLDER AIR EVENTUALLY FUNNELS INTO THE GREAT LAKES FROM CANADA IN BEHIND THE SYSTEM. WITH THIS IDEA OF COOLING INTO THE WEEKEND...WILL GO OPPOSITE OF THE CLIMATOLOGY INDUCED RISE IN MEX GUIDANCE FROM FRIDAY INTO SATURDAY. AT BEST...WILL KEEP FRIDAY/SATURDAY VERY CLOSE TO THE SAME...WITH A FEW DEGREE RISE BY SUNDAY. && .DTX WATCHES/WARNINGS/ADVISORIES... .MI...NONE. .LAKE HURON... GALE WARNING...FOR THE SOUTH HALF...THROUGH SUNDAY MORNING. GALE WARNING...FOR THE NEARSHORE WATERS EXCLUSIVE OF INNER SAGINAW BAY...OVERNIGHT. SMALL CRAFT ADVISORY...INNER SAGINAW BAY...OVERNIGHT. .LAKE ST CLAIR...GALE WARNING...THROUGH SUNDAY MORNING. .MI WATERS OF LAKE ERIE...GALE WARNING...OVERNIGHT. && $$ DWD/BRAVENDER/DEG mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 1047 AM EDT SUN APR 3 2005 .DISCUSSION... THE MAIN CONCERN WITH THIS UPDATE IS THE HIGH TEMPERATURES FOR THIS AFTERNOON. WATER VAPOR IMAGERY AND RUC/ETA SHOWING A SPLIT FLOW ACROSS EASTERN CONUS. THE SOUTHERN SPLIT SWING AROUND A LOW OVER NEW YORK STATE...WHERE AS THE NORTHERN SPLIT SAILS THROUGH ONTARIO. A BROAD RIDGE APPEARS TO OCCUPY MUCH OF NORTHERN PLAINS. A DEEP LOW IS OFF THE WEST COAST. A WEAK SHORTWAVE IS ON THE WEST END OF THE U.P. TRYING TO MAKE UP ITS MIND WHICH SPLIT IT WILL TAKE. AN AREA OF 850-500MB Q-VECTOR CONVERGENCE IS ACROSS CENTRAL ONTARIO AND THE CENTRAL PART OF THE FORECAST AREA INTO SOUTHWEST WISCONSIN PRODUCING A BAND OF ALTO CUMULUS AROUND 8K FEET. SURFACE ANALYSIS DEPICT A CLOSED LOW OVER NEW YORK STATE...AND A RIDGE RUNNING THE LENGTH OF THE MISSISSIPI RIVER VALLEY TO A HIGH OVER WESTERN ONTARIO. A LOW IS DEVELOPING OVER THE NORTHERN HIGH PLAINS. THE SHORTWAVE OVER THE U.P. WILL WEAKEN EVEN MORE UNDER THE REGIME OF THE SPLIT FLOW AS IT MOVES INTO THE CENTRAL PART OF THE FORECAST AREA. THE SURFACE LOW WILL MOVE TO THE ALBANY NEW YORK AREA...WHILE THE RIDGE RELOCATES OVER THE FORECAST AREA AND EASTERN WISCOSIN. THE HIGH PLAINS LOW WILL PUSH INTO SOUTHEAST MONTANA WHILE DIRECTING A WARM FRONT OUT A HEAD OF IT THROUGH SOUTH DAKOTA. THUS CONDITIONS SHOULD REMAIN FAIRLY SUNNY AND MILD ACROSS THE FORECAST AREA THIS AFTERNOON. WINDS WILL BE LIGHT ACROSS THE AREA THIS AFTERNOON...SO CONDITIONS FAVOR SOLAR HEATING. && .MQT...WATCHES/WARNINGS/ADVISORIES...NONE. && $$ DLG mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NORMAN OK 1058 AM CDT SUN APR 3 2005 CHALLENGING FORECAST THIS AFTERNOON WITH ANY CHANGES THAT HAVE BEEN CONSIDERED BASED ON THICKENING CIRRUS...WHICH IS USUALLY DIFFICULT TO PREDICT...AND RECENT MODEL BIASES IN 2M DEWPOINTS. SHORTWAVE RIDGE NOW OVER THE REGION WITH ASSOCIATED DEFORMATION INCREASING DUE TO APPROACH OF A SHORTWAVE TROUGH OVER THE ROCKIES. COMBINED WITH LIFT OVER THE MOUNTAINS...CIRRUS HAS INCREASED OVER THE ENTIRE AREA. CIRRUS SHOULD GENERALLY INCREASE/THICKEN AS THE DAY PROGRESSES WITH FLUCTUATIONS EXPECTED IN ITS DEVELOPMENT. FORECAST HIGHS MAY NEED TO BE ADJUSTED DOWNWARD IN THE WEST...PARTICULARLY THE NORTHWEST WHERE CLOUDS ARE THICKEST. CIRRUS CAN BE VERY TRICKY...SO WILL NOT MAKE MAJOR TEMP CHANGES. THE OTHER CONCERN IS DEWPOINTS. THE RUC CONTINUES TO DISPLAY A DRY BIAS...PERHAPS DUE TO INITIALIZATION OF FICTITIOUSLY DRY SOIL WHICH HAS PLAGUED THE MODEL FOR SOME TIME. MEANWHILE...THE ETA/GFS HAVE BEEN TOO MOIST. MODEL PERFORMANCE THE LAST 2 DAYS SUGGESTS A COMPROMISE BETWEEN THE ETA AND RUC HAS BEEN MOST USEFUL. THUS HAVE USED THIS APPROACH TO LOWER DEWPOINTS FOR THIS AFTERNOON...BUT NOT AS MUCH AS THE RUC INDICATES. RELATIVE HUMIDITIES WILL BE SLIGHTLY LOWER MOST AREAS AS A RESULT. JAMES ----------------------- 416 AM CDT SUN APR 3 2005 .DISCUSSION... MAIN CONCERNS THIS MORNING ARE FIRE WX IN SHORT TERM...AND SYSTEM MOVING INTO PLAINS TUE-WED. TEMPS WILL EXCEED RED FLAG THRESHOLD TODAY IN ALL AREAS...BUT WIND/RH PROGGED TO BE MARGINAL. WE THINK AT LEAST 2 OF THE 3 CRITERIA WILL BE MET OVER MOST OF THE FIRE WX WATCH AREA THIS AFTERNOON...SO WE WILL UP TO A RED FLAG WARNING. EXPECT CIRRUS TO INCREASE AND GRADUALLY THICKEN DURING DAY BASED ON SATELLITE TRENDS AND MODEL HIGH-LEVEL RH PROGS...BUT THICKER STUFF NOT EXPECTED UNTIL AFTER MOST AREAS HAVE HAD PLENTY OF DAYTIME WARMING SO EXPECT MINIMAL EFFECT ON HIGH TEMPS. CONSENSUS OF THE MODELS - AT LEAST THE NCEP RUNS - IS FOR A SLIGHTLY FASTER SYSTEM TRACKING A BIT FARTHER N TUE/WED. ONCE AGAIN WE WILL LIKELY DEAL WITH A POTENT DYNAMIC SYSTEM THAT WILL HAVE WRETCHED LOW-LEVEL MOISTURE TO WORK WITH THIS FAR W...SO THE MAIN STORY APPEARS MORE LIKELY TO BE GRADIENT WINDS RATHER THAN SEVERE STORMS. GULF HAS BEEN SCOURED AGAIN...WITH CURRENT DEWPOINTS ONLY IN THE 40S IN W GULF. RETURN FLOW OF MODIFIED GULF AIR WILL LIKELY BRING DEWPOINTS BACK INTO 50S BY TUE...BUT FASTER SYSTEM MEANS DRYLINE LIKELY TO PUNCH ACROSS MOST OF AREA WELL BEFORE MAX HEATING OCCURS ON TUE. WE HAVE MODIFIED THE DEWPOINT GRIDS TO SLOW DOWN THE PROGRESSION OF DRY AIR SLIGHTLY BASED ON TYPICAL MODEL TENDENCY TO PUSH THE DRYLINE E TOO QUICKLY AT TIME RANGES OF 2-3 DAYS. THAT STILL CARRIES THE DRYLINE INTO CENTRAL OK NEAR OR BEFORE 18Z TUE...AND INTO E OK OUT OF OUR CWA BY 21Z. HAVE TRENDED POPS DOWN ON TUE TO ACCOUNT FOR FASTER MOVEMENT...AND MAY WELL NEED TO LOWER THEM MORE AS THE SYSTEM DRAWS CLOSER...ONCE IT BECOMES MORE CERTAIN THAT MUCH OF THE CWA WILL BE DRY SLOTTED. ENERGETIC SYSTEM WITH STRONG WIND FIELDS AND DECENT POST-DRYLINE MIXING INDICATE STRONG SW-W WINDS TUE... BECOMING NW TUE NIGHT AS SFC LOW MOVES NE. MAY BE A WIND ADVISORY SITUATION. BEST CHANCE OF RAIN NOW MORE LIKELY TO BE WITH WRAPAROUND RA/SHRA ACROSS MAINLY N OK LATE TUE INTO WED WITH S PARTS OF CWA REMAINING DRY. NO SIGNIFICANT CHANGES BEYOND WED EXCEPT TO LOWER TEMPS THU/FRI AS SFC HIGH SETTLES IN BEHIND THE DEPARTING SYSTEM. ANOTHER SYSTEM IS PROGGED TO APPROACH FROM THE 4-CORNERS AREA LATE SAT OR SUN. BUT IN KEEPING WITH THE THEME SO FAR THIS SEASON... WILL NOT INTRODUCE ANY POPS AS GULF AGAIN WILL BE SCOURED OUT IN WAKE OF THE MID-LATE WEEK SYSTEM. && .PRELIMINARY POINT TEMPS/POPS... OKLAHOMA CITY OK 78 53 80 59 / 0 0 10 10 HOBART OK 81 53 83 57 / 0 0 10 10 WICHITA FALLS TX 80 54 83 59 / 0 0 10 10 GAGE OK 82 49 86 51 / 0 0 10 20 PONCA CITY OK 80 56 80 62 / 0 0 10 10 DURANT OK 78 56 77 62 / 0 0 10 10 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...RED FLAG WARNING FROM NOON SUNDAY TO 7 PM SUNDAY FOR OKZ004- OKZ005-OKZ006-OKZ007-OKZ008-OKZ009-OKZ010-OKZ011-OKZ012- OKZ013-OKZ014-OKZ015-OKZ016-OKZ017-OKZ018-OKZ019-OKZ020- OKZ021-OKZ022-OKZ023-OKZ024-OKZ025-OKZ026-OKZ027-OKZ028- OKZ029-OKZ030-OKZ031-OKZ033-OKZ034-OKZ035-OKZ036-OKZ037- OKZ038-OKZ039-OKZ040-OKZ041-OKZ042-OKZ044-OKZ045-OKZ046- OKZ050. TX...RED FLAG WARNING FROM NOON SUNDAY TO 7 PM SUNDAY FOR TXZ083- TXZ084-TXZ085-TXZ086-TXZ087-TXZ088-TXZ089-TXZ090. && $$ 30 SHORT TERM / 24 LONG TERM ok AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE PUEBLO CO 237 PM MDT SUN APR 3 2005 .SHORT TERM... (TONIGHT AND MONDAY) MAIN SHORT TERM CONCERNS INCLUDE TEMPERATURES AND WINDS WITH PRECIP CHANCES ACROSS WESTERN PARTS OF AREA TOMORROW. CURRENT WATER VAPOR IMAGERY AND RUC UPPER AIR ANALYSIS INDICATING FLAT UPPER LEVEL RIDGING ACROSS THE INTERMOUNTAIN WEST...AS A BROAD EASTERN PACIFIC UPPER TROUGH DIGS ACROSS THE PAC NW COAST WITH 90+ KT JET CORE ROUNDING THE BASE OF THE SYSTEM AND INTO THE NORTHERN GREAT BASIN ATTM. WATER VAPOR ALSO INDICATING SUBTROPICAL MOISTURE PLUME MOVING ACROSS THE DESERT SW THROUGH SOUTHEASTERN COLORADO AND INTO THE CENTRAL HIGH PLAINS...WITH DISTINCT CLEARING BEING NOTED ACROSS WESTERN COLORADO ATTM. CLOUDS HAVE HAMPERED EXPECTED MIXING AND HEATING ACROSS THE FAR EASTERN PLAINS...HOWEVER...WITH CLEARING SKIES FROM WEST TO EAST ALONG WITH A LATER SUNSET...SHOULD STILL SEE TEMPERATURES INTO THE LOWER TO MID 70S LATE THIS AFTERNOON. TONIGHT...SOUTHWEST FLOW INCREASES ACROSS THE REGION AS PAC NW SYSTEM CONTINUE TO DIG ACROSS THE GREAT BASIN...WITH H5 WINDS INCREASING TO BETWEEN 35-45 KTS AND H7 WINDS OF 15-25 KTS BY 12Z MON. INCREASING SW FLOW PUSHES LEE TROUGH ACROSS THE WESTERN KANSAS BORDER OVERNIGHT...KEEPING WESTERLY FLOW AND MIN TEMPS UP ACROSS THE REGION. CLEARING ACROSS REGION THIS EVENING WILL BE SHORT LIVED AS INCREASING HIGH LEVEL MOISTURE ACROSS WESTERN UTAH MOVES ACROSS THE STATE OVERNIGHT. MONDAY...UPPER TROUGH CONTINUES TO MOVE ACROSS THE GREAT BASIN WITH TIP OF 90KT JET CORE NOSING INTO WESTERN COLORADO BY 00Z TUE. H5 AND H7 FLOW INCREASES TO AROUND 50 KT AND 30KTS RESPECTIVELY...WITH BREEZY TO WINDY CONDITIONS DEVELOPING ACROSS THE HIGHER TERRAIN. WITH INCREASED UVV AND PROXIMITY OF JET CORE...HAVE KEPT SCATTERED SHOWERS AND ISOLATED TSRASN ACROSS THE SW AND CENTRAL MTS MON AFTERNOON WITH ISOLATED POPS SPREADING ACROSS THE HIGH MT VALLEYS THROUGH THE EASTERN MTS. ANY ACCUMULATIONS EXPECTED TO BE ON THE LIGHT SIDE EVEN WITH GOOD UPPER SUPPORT AS LOW LEVEL MOISTURE LACKING. ACROSS THE EASTERN PLAINS...EXPECTING GOOD MIXING WITH LAPSE RATES AROUND 8C/KM...ALLOWING FOR GUSTY SOUTHWEST WINDS OF 15 TO 30 MPH MIXING DOWN ACROSS THE AREA IN THE AFTERNOON. WITH GOOD DOWNSLOPE WARMING...HAVE GONE ABOVE GUIDANCE TEMPS FOR HIGHS ON MONDAY. ONLY WRENCH TO CURRENT FORECAST WILL BE THE BOUTS OF HIGH LEVEL CLOUDS MOVING ACROSS THE REGION HAMPERING MIXING...THOUGH CLOUDS ARE NOT EXPECTED TO BE AS DENSE AS TODAY. -MW .LONG TERM... (TUESDAY THROUGH SUNDAY) MAIN CONCERN CONTINUES TO FOCUS ON THE NEXT UPPER TROUGH THAT WILL BE THE PRIMARY WEATHER MAKER MONDAY NIGHT THROUGH WEDNESDAY. NAM SEEMS TO BE THE ODD MODEL OUT AT THIS POINT POSSIBLY DUE TO ITS INITIALIZATION AT 12Z. LOOKS LIKE IT IS TOO STRONG WITH THE UPPER RIDGE AND THAT IS FORCING IT TO MOVE THE LOW TOO FAR NORTH AND TOO FAST. GFS AND OTHERS TRENDING TOWARD A DEEPER LOW FARTHER SOUTH. STRONG WINDS DIVE INTO THE BACK SIDE OF THE TROF AS IT MOVES TO OUR EAST. THIS SETS UP A DEEP LAYER OF WINDS GREATER THAN 40 KTS. MODELS SHOWING 50-60 KNOTS AT 700 MB ON TUESDAY WITH LAPSE RATES SUFFICIENT TO MIX THAT DOWN TO THE SURFACE. GOOD COLLABORATION WITH SURROUNDING WFOS TO SUPPORT HIGH WIND WATCH FOR TUESDAY. PRECIPITABLE WATER IS LACKING WITH THIS SYSTEM AND ALTHOUGH SIMILAR IN STRENGTH TO LAST THURSDAY STORM THIS ONE IS NOT AS COLD OR AS WET. WIND TRAJECTORIES SUGGEST MORE OF A NORTH TO NORTH WEST COMPONENT THAT WILL LIMIT ANY TERRAIN ENHANCEMENT. RAISED POPS A TAD OVER EASTERN ZONES BUT STILL KEPT THEM IN THE CHANCE CATEGORY. IF LOW DEEPENS FARTHER WEST WE MAY NEED TO REEVALUATE THAT ISSUE BUT THAT CAN WAIT UNTIL TOMORROW. THE SYSTEM MOVES THROUGH FAIRLY FAST AND UPPER RIDGE BUILDS IN TO WARM US UP FROM WEDNESDAY THROUGH SATURDAY. NEXT CONCERN SHOWS UP AT THE END OF THE WEEK WHEN ANOTHER UPPER TROF PUSHES IN FROM THE WEST. GFS AND DGEX ARE FARTHER SOUTH WITH THIS SYSTEM TO BEGIN WITH SO IT COULD BE MORE OF A PRECIPITATION MAKER. IF WE CAN TAP INTO SOME GULF MOISTURE COULD SEE A MORE CONVECTIVE DRYLINE EVENT DURING PEAK HEATING ON SATURDAY. ADDED SOME LOW POPS AND THUNDER FOR SATURDAY AFTERNOON. HELD TO CURRENT FORECAST SATURDAY NIGHT AND SUNDAY. -WF && .PUB WATCHES/WARNINGS/ADVISORIES... HIGH WIND WATCH FROM 6 AM TUESDAY TO 6 PM TUESDAY FOR COZ084- COZ085-COZ086-COZ089-COZ093-COZ094-COZ095-COZ096-COZ097-COZ098- COZ099. && $$ 23/21 co AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DES MOINES IA 310 PM CST SUN APR 3 2005 .DISCUSSION... STRONG SHRT WV CURRENTLY JUST OFF OF THE CALIFORNIA COAST WL BECOME THE MAIN FORECAST CONCERN OVER THE NEXT SEVEN DAYS AND AFFECT THE CENTRAL PLAINS TUESDAY THROUGH THURSDAY. TONIGHT AND MONDAY...THE FOCUS WILL BE TEMPERATURES WITH DEVELOPING SOUTHERLY FLOW ACROSS IOWA DURING THE PERIOD. TEMPERATURE TODAY HAVE RISEN INTO THE LOWER 70S ACROSS MUCH OF THE STATE. EXPECT TO ADD ANOTHER 5 DEGREES TO THIS ON MONDAY. A LARGE AMOUNT OF UNCERTAINTY EXISTS WITH THE POTENT SHRT WV AS IT ENTERS THE CENTRAL PLAINS AS MODEL SOLUTIONS WITH THE SFC LOW RANGE FROM THE NGM ACRS SE NORTH DAKOTA TO NORTHERN TEXAS ON THE CANADIAN. THE RUC13/NAM/GFS MORE FOCUSED OVER THE MIDWEST WITH THE NAM BEING THE COMPROMISE SOLUTION OF THE THREE. THE 12Z NAM SOLUTION WOULD SUGGEST A SIGNIFICANT SEVERE OUTBREAK ACRS CNTRL IA LATE TUESDAY AFTERNOON. AT THIS TIME...AM PREFERRING A FARTHER SOUTH SOLUTION AND THEREFORE WILL NOT INCREASE SEVERE MENTION IN THE HWO. ALSO DUE TO UNCERTAINTIES...HAVE REMAINED CONSISTENT WITH INHERITED FORECAST FOR TUESDAY AND WEDNESDAY. && .LONG TERM...(THURSDAY-SUNDAY) LATEST TRENDS ARE FOR THE SYSTEM TO BECOME STACKED OVER THE REGION AND WILL SLOW THE EASTWARD PROGRESSION. HAVE ADDED PRECIPITATION MENTION FOR THURSDAY WITH LINGERING WRAP AROUND ACTIVITY. HAVE ALSO KEPT PRECIPITATION AS LIQUID WILL LITTLE TRUE COLD AIR BEING WRAPPED INTO THE SYSTEM. HAVE UNDERCUT GUIDANCE BY 5 DEGREES ON THURSDAY DUE TO CLOUD COVER AND EXPECTED LIMITED RECOVERY. A RIDGE OF HIGH PRESSURE BUILDS INTO THE REGION FRIDAY AND SATURDAY WITH MODERATING TEMPERATURES. ANOTHER LONG WAVE TROUGH MOVES INTO THE WESTERN PLAINS ON SUNDAY AND WILL BRING THE NEXT CHANCE OF PRECIPITATION. && .DMX WATCHES/WARNINGS/ADVISORIES...NONE. && $$ DONAVON ia AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GOODLAND KS 245 PM MDT SUN APR 3 2005 .SHORT TERM... (TONIGHT-WED) FORECAST PROBLEMS WILL BE TEMPERATURES ON MONDAY...THEN CHANCE OF PRECIPITATION AND WIND MONDAY NIGHT THROUGH WEDNESDAY. TEMPERATURES ON MONDAY WILL ONCE AGAIN DEPEND ON EXTENT OF CLOUD COVER. MODELS SHOWING SCATTERED-BROKEN DECK AT 10KFT SPREADING WEST TO EAST ACROSS THE FORECAST AREA. SURFACE WINDS LOOK BETTER COMPARED TO TODAY...WITH SOUTHWEST WINDS DEVELOPING IN ALL BUT THE NEBRASKA COUNTIES...BUT STILL WITH WIND SPEEDS OFF THE RUC STAYING IN THE 10-15KT RANGE CLOUD COVER WILL BE THE DETERMINING FACTOR. CONSEQUENTLY WILL LOWER MAXES ABOUT A CATEGORY IN THE WEST. COLD FRONT WILL APPROACH YUMA COUNTY AROUND 06Z MONDAY NIGHT AND EXPECTED TO BE ALONG A MCCOOK TO TRIBUNE LINE AROUND 12Z TUESDAY MORNING. DEEPEST MOISTURE WILL NOT ARRIVE UNTIL WELL AFTER FRONTAL PASSAGE AND WILL CUT POPS BACK ANOTHER 10 PERCENT FOR MONDAY NIGHT LEAVING ONLY AREAS WEST OF FRONTAL POSITION WITH ANY MENTION AT ALL. TUESDAY WILL BE AN ACTIVE WEATHER DAY. UKMET THE FAVORED SOLUTION FOR TRACK OF UPPER LOW...ALONG OR JUST NORTH OF THE OKLAHOMA/KANSAS BORDER. CYCLOGENESIS EXPECTED TO OCCUR NEAR HILL CITY BEFORE SYSTEM BECOMES VERTICALLY STACKED NEAR DODGE CITY. WIDESPREAD RAIN WILL DEVELOP ACROSS THE CWA AS DEFORMATION ZONE MOVES WEST TO EAST. SLOWER UKMET SOLUTION FAVORS EXTENDING CHANCE TO LIKELY POPS INTO TUESDAY NIGHT ACROSS ALL BUT THE FAR WESTERN ZONES...AND THEN LOW CHANCES EARLY WEDNESDAY IN THE FAR EASTERN ZONES. BIGGER STORY WILL BE THE WIND. PRESSURE RISES WILL BE SHARP BEHIND THE FRONT TUESDAY MORNING. 0-1KM WINDS INCREASE TO 40-50KTS FROM WEST TO EAST DURING THE DAY ON TUESDAY AND DO NOT FALL BELOW THAT VALUE UNTIL WEDNESDAY AFTERNOON AS PRESSURE GRADIENT GRADUALLY RELAXES. WILL ISSUE A RATHER LONG HIGH WIND WATCH IN COORDINATION WITH SURROUNDING OFFICES TO COVER ALL THE POSSIBILITIES...12Z TUESDAY TO 00Z THURSDAY. .LONG TERM... (THU-SUN) FORECAST PROBLEMS WILL BE TEMPERATURES EARLY IN THE PERIOD THEN CHANCES OF PRECIPITATION LATE IN THE PERIOD. ON THURSDAY THE HIGH PLAINS WILL BE UNDER AMPLIFIED RIDGE AXIS WITH DEEP TROUGHS ON BOTH COASTS OF THE CONUS. LOW LEVEL THERMAL RIDGE AXIS WILL BE CLOSE TO THE FRONT RANGE OF COLORADO. PROBLEM FOR A DRAMATIC WARM UP STILL APPEARS TO BE EASTERLY COMPONENT TO SURFACE WINDS RESULTING FROM SURFACE RIDGE NOSING INTO THE CENTRAL PLAINS. THEN ON FRIDAY HEIGHT FALLS OVER THE ROCKIES AHEAD OF NEXT SYSTEM WILL INDUCE LEE TROUGH OVER EASTERN COLORADO...FURTHER REINFORCING SOUTHEASTERLY SURFACE WIND FIELD. WILL GO CONSERVATIVE WITH TEMPERATURES BOTH THESE DAYS. UPPER LEVEL SYSTEM WILL BE APPROACHING THE SOUTHERN ROCKIES NEXT WEEKEND. CANADIAN GLOBAL SIGNIFICANTLY SLOWER AT 00Z/09 AND ECMWF SLIGHTLY SLOWER AT 00Z/10. GFS TENDS TO BE BIASED TOWARDS DEEP AND FAST SOLUTIONS IN THE LONGER RANGES. MOISTURE INFLUX LOOKS TO BE GOOD WITH GULF OF MEXICO OPEN...HOWEVER ANY LEAD SHORTWAVES MAY TRIGGER CONVECTION TO THE SOUTH AND ROB THAT MOISTURE SOURCE. NONETHELESS...SYSTEM APPEARS VIGOROUS AND EJECTS WITH A SLIGHT NEGATIVE TILT. WILL KEEP SATURDAY DRY AND WARM BUT INTRODUCE SLIGHT CHANCE FOR -TRW ON SUNDAY. && .GLD WATCHES/WARNINGS/ADVISORIES... .KS...HIGH WIND WATCH 12Z TUESDAY TIL 00Z THURSDAY. .NE...HIGH WIND WATCH 12Z TUESDAY TIL 00Z THURSDAY. .CO...HIGH WIND WATCH 12Z TUESDAY TIL 00Z THURSDAY. && $$ JDK ks AREA FORECAST DISCUSSION...UPDATE NATIONAL WEATHER SERVICE GOODLAND KS 1255 PM MDT SUN APR 3 2005 .DISCUSSION...TEMPERATURES NOT WARMING UP IN THE WEST AND STILL A LONG WAY FROM FORECAST MAXES. WILL TWEEKING MAXES DOWN ONE MORE TIME IN THIS AREA. WIND FIELD ALL OVER THE PLACE WITH SURFACE LOW NEAR HILL CITY AND DEVELOPING TROUGH TO THE WEST. UPDATED WITH REALITY AND RUC. && .GLD WATCHES/WARNINGS/ADVISORIES... .KS...NONE. .NE...NONE. .CO...NONE. && $$ BULLER ks AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LOUISVILLE KY 225 AM EST SUN APR 3 2005 .SHORT TERM:(TONIGHT THROUGH WED AFTN) MAJOR TECHNICAL PROBS OF NOTE: WE ARE HAVING MAJOR PROBLEMS AT LMK GETTING GFS...LAPS...RUC DATA OVR WEEKEND...A DIFFICULT PROBLEM FOR NCF TO SOLVE...SOME TYPE OF HW AND/OR SW PROBLEMS INVOLVED. WE HOPE TO HAVE THIS FIXED ON MONDAY. BUT...SOME OF THE MISSING DATA AVAILABLE OVER THE INTERNET WITH OUR OFFICE PC'S. 500 MB RDG WILL SHIFT EWRD ACRS FA DURING THE NEXT COUPLE OF DAYS AS ANOTHER MAJOR TROF DROPS E OF THE CENTRAL ROCKIES DURING MON NIGHT AND THEN EASTWARD INTO THE CENTRL U.S. ON TUESDAY NIGHT AND WED. DRY AND MILDER WEATHER TONIGHT INTO TUESDAY...WI TEMP AND DEWPOINT TRENDS THE ONLY MAJOR PROBLEM TO DEAL WITH. PREV FCSTS TRENDS MORE OR LESS IN LINE WI EXPECTED SCENARIO AND AVAILABLE MODEL DATA...SO ONLY MINOR TWEAKS NEEDED. GFS SERIES AS WELL AS OUR SURROUNDING OFFICES INTOD A CHC OF PCPN DURING TUE NIGHT...THIS IS IN LINE WITH THE PATTERN CHANGES MENTIONED' ABOVE...SO WE WILL INTRO CHC OF TRW- WRN THIRD OF FA DURING TUE NIGHT AND CONT ACROSS FA IN LIKELY CATEGORY DURING THE DAY ON WED. IN THE EXTENDED...(WEDNESDAY NIGHT THROUGH SATURDAY)... DECENT MODEL CONTINUITY FROM THIS MORNING AND YSTDYS RUNS FOR THE EXTENDED PERIOD...HAVE USED A BLEND OF THE ENSEMBLE SOLUTIONS OF THE GFS AND ECMWF. THEREFORE LITTLE WAS CHANGED FROM PREVIOUS FORECAST PACKAGE...BUT JUST SOME MINOR TWEAKS TO TEMPS AND POPS. AN AREA OF LOW PRESSURE WILL BE MOVING ACROSS THE MS VALLEY INTO THE OH VALLEY WEDNESDAY NITE INTO THURSDAY MORN...WITH A CUT OFF UPPER LEVEL LOW SLOWLY SLIDING ACROSS THE FORECAST AREA THRU EARLY MORNING FRIDAY. CHANCES FOR PRECIP WILL BE GREATEST WED NITE THRU THURSDAY MORN...A FEW THUNDERSTORMS WILL BE POSSIBLE WEDNESDAY NITE AS THE FRONT PUSHES THRU THE OH VALLEY...WITH SHOWERS FROM THE WRAP AROUND MOISTURE BEHIND THE SYSTEM. TEMPS WILL BE BELOW NORMAL FOR THURSDAY AND JUST BELOW NORMAL FOR FRIDAY. EVERYONE SHOULD DRY OUT BY FRIDAY MORN AS RIDGING STARTS TO WORK ITS WAY INTO THE OH VALLEY BY LATE FRIDAY OR EARLY SATURDAY...WITH WARMING FOR THE WEEKEND AND ABV NORMAL TEMPS FOR SUNDAY AS THE RIDGE STAYS ACROSS THE REGION FOR THE ENTIRE WEEKEND. .LMK WATCHES/WARNINGS/ADVISORIES... .IN...NONE. .KY...NONE. && $$ DK ky AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 330 PM EDT SUN APR 3 2005 .SHORT TERM...TONIGHT AND MONDAY 12Z RAOBS/WATER VAPOR LOOP SHOW UPPER LOW OVER NEW YORK...WITH SHORTWAVE RIDGE BUILDING INTO THE WESTERN GREAT LAKES. SURFACE ANALYSIS SHOWS LOW NEAR EASTERN LAKE ONTARIO AND RIDGE UPSTREAM ACROSS WISCONSIN...WITH A STRONG GRADIENT REMAINING ACROSS SOUTHEAST MICHIGAN AND THE CENTRAL GREAT LAKES. VIS SATELLITE/METARS SHOW THE MID/HIGH CLOUDS THAT HAD WRAPPED BACK ACROSS THE EASTERN CWA HAVE DIMINISHED...LEAVING SUNNY SKIES ACROSS MUCH OF THE STATE. WITH NO ECHOES ON DTX RADAR...VWP IS CLEAR OF RETURNS. HOWEVER RECENT TAMDAR SOUNDINGS SHOW WINDS IN THE MIXED LAYER HAVE DIMINISHED OVER THE LAST FEW HOURS...BUT ARE STILL RUNNING 35KTS /+60KT JET WELL ABOVE THE INVERSION STILL OVER THE REGION/. WINDS ARE STILL QUITE GUSTY...AND SHOULD REMAIN SO THROUGH SUNSET...BEFORE STABILIZING BOUNDARY LAYER AND WEAKENING GRADIENT BOTH WORK TO LIGHTEN THE WINDS. HAD ALREADY SLOWED THE DECREASE IN WINDS WITH THE EARLIER UPDATE /ESPECIALLY MARINE AREAS/ AND WILL DO SO AGAIN. WITH THIS IN MIND...NOT SURE HOW GOOD OUR CHANCES ARE TO DECOUPLE EVEN UNDER CLEAR SKIES AND DRY AIRMASS...AS WINDS MAY STAY UP ENOUGH TO KEEP US BETTER MIXED OVERNIGHT. SURFACE RIDGE BUILDS ACROSS LOWER MICHIGAN ON MONDAY...KEEPING WINDS DOWN DURING THE DAY AS WELL. FORECAST SOUNDINGS SHOW SOME WARM ADVECTION PICKING UP ALOFT DURING THE DAY. THE GENERALLY WARMER AIRMASS SHOULD TRANSLATE TO TEMPS A FEW DEGREES HIGHER THAN TODAY /NEAR 60 ESPECIALLY SOUTH/...ALTHOUGH WE WILL NOT MIX AS DEEP WITH A STRONGER INVERSION. CROSS SECTIONS BEGIN TO SHOW AN INCREASE IN MID/UPPER LEVEL MOISTURE DURING THE AFTERNOON...AS CIRRUS FROM THE PLAINS WORKS IN ACROSS THE REGION. HOWEVER THE COLUMN REMAINS RATHER DRY...AND SUNNY/MOSTLY SUNNY SKIES STILL LOOK GOOD. && .LONG TERM...MONDAY NIGHT THROUGH SUNDAY. A MORE SPRING-LIKE PATTERN TO HOLD THROUGH THE EXTENDED FORECAST. THIS BASICALLY FOR THE FIRST TIME THIS SEASON. WILL STILL HAVE TO DEAL WITH STORM SYSTEM THAT DEVELOPS OVER THE OHIO/TENNESSEE VALLEY REGIONS AND GRADUALLY JUMPS OVER TO THE EAST COAST MID/LATE WEEK. PRECIPITATION FROM THIS SYSTEM WILL BE ALL RAIN...WITH STILL A HINT AT A FEW THUNDERSTORMS. THIS HINT...HOWEVER...IS ALL THERE IS WITH BASICALLY JUST A RUMBLE OF THUNDER POSSIBLE NOW AND AGAIN WITH THE AREA OF RAIN. WILL DELAY RAIN CHANCES A BIT MORE (STARTING ON WED EVENING) AS MODELS HAVE TRENDED SLOWER. ON THE OTHER END...SHOWER CHANCES STILL APPEAR GOOD INTO THURSDAY NIGHT...WITH DRY WEATHER ON FRIDAY. THIS IS A CLOSE CALL...BUT WILL KEEP THE PREVIOUS FORECAST INTACT. WILL KEEP DRY FORECAST THROUGH THE UPCOMING WEEKEND AS NEXT TROUGH IS SLOW TO MOVE EAST TOWARD THE AREA IN A MORE BLOCKED PATTERN WILL NOT CHANGE MUCH IN THE WAY OF TEMPERATURES...WITH 60S PREVALENT INTO TUESDAY/WEDNESDAY...COOLING TO 50S THURSDAY INTO THE WEEKEND W/ A REBOUND BACK INTO THE 60S BY THE END OF THE FORECAST PERIOD AS MID WEEK STORM CENTERS OFF THE NEW ENGLAND COAST...AND AN UPPER RIDGE TRANSLATES JUST FAR ENOUGH EAST TO BRING A MODERATING TREND. && .AVIATION...ISSUED AT 130 PM EST. VFR CIG/VIS THIS TAF PERIOD. WINDS CONTINUE TO BE STRONG AND GUSTY...WITH TIGHT PRESSURE GRADIENT BEHIND A PRETTY DEEP LOW MOVING ACROSS NEW YORK STATE. 12Z RUC/NAM CONTINUE TO SHOW DECENT WINDS PERSISTING ACROSS SOUTHEAST MICHIGAN THROUGH THE AFTERNOON. TAMDAR SOUNDINGS VICINITY OF DTW INDICATE MIXING UP TO 2-3KFT AGL...TAPPING INTO 35-40KTS OF THE 50-55KT LOW-LEVEL JET. GRADIENT WILL CONTINUE TO DIMINISH THROUGH THE DAY...ALREADY SEEN IN SOMEWHAT LIGHTER WINDS ACROSS THE SAGINAW VALLEY. WILL DROP WIND SPEEDS AND GUSTINESS AT TAF SITES THROUGH THE EVENING...ESPECIALLY OVERNIGHT AS WE LOSE THE DIURNAL MIXING. WIND SHEAR SHOULD NOT BE AN ISSUE TONIGHT AS THE LOW-LEVEL JET PULLS EAST AS WE START TO STABILIZE NEAR THE SURFACE. HIGH PRESSURE BUILDS ACROSS THE STATE ON MONDAY...ALLOWING WIND SPEEDS TO DROP EVEN FURTHER. && .DTX WATCHES/WARNINGS/ADVISORIES... .MI...NONE. .LAKE HURON... GALE WARNING...SOUTH HALF...THIS EVENING. SMALL CRAFT ADVISORY...SAGINAW BAY...EARLY THIS EVENING. .LAKE ST CLAIR...GALE WARNING...THIS EVENING. .MI WATERS OF LAKE ERIE...SMALL CRAFT ADVISORY...THIS EVENING. && $$ BRAVENDER/DEG mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 324 PM EDT SUN APR 3 2005 .DISCUSSION... MAIN FORECAST CONCERNS ARE TEMPERATURES AND THE MID-WEEK SYSTEM. CURRENT WEATHER...18Z WATER VAPOR LOOP AND RUC 500MB HEIGHT ANALYSIS SHOWED AN UPPER LOW SITUATED OVER NEW YORK STATE...RIDGING ACROSS THE PLAINS AND A TROUGH COMING ONSHORE ALONG THE WEST COAST. A STRONG SHRTWV EVIDENT LOCATED AT THE BASE OF THE TROUGH IS PROGGED TO BE THE SHRTWV THAT IS THE BIG WEATHER MAKER FOR MID-WEEK. STREAKS OF UPPER LEVEL MOISTURE ON WATER VAPOR CAN BE SEEN MOVING FROM THE PACIFIC AHEAD OF THE TROUGH INTO THE PLAINS...WHICH SHOWS UP AS CIRRUS ON VISIBLE SATELLITE IMAGERY AND SURFACE OBS. WEST/SW FLOW ALOFT DOWNSLOPING INTO THE PLAINS HAS RESULTED IN LEE TROUGHINESS ALONG THE ROCKIES...WITH SURFACE LOWS EVIDENT NEAR DENVER AND BILLINGS. WARM FRONTS EXTEND EAST FROM EACH LOW...WITH THE DENVER ONE ALONG I-70 AND THE OTHER TOWARDS ABERDEEN. WITH UPPER MICHIGAN ON THE EAST SIDE OF THE UPPER LEVEL RIDGE AXIS...HIGH PRESSURE COVERS THE AREA. LIGHT WINDS ASSOCIATED WITH THE HIGH COMBINED WITH STRONG SURFACE HEATING IN THE INTERIOR (WHERE TEMPERATURES ARE CURRENTLY IN THE 50S TO NEAR 60) HAS RESULTED IN THE DEVELOPMENT OF LAKE BREEZES. 850MB TEMPS ON THE 12Z RAOBS WERE AROUND 1C OVER UPPER MICHIGAN...WHICH MIXING OUT PRODUCES THOSE READINGS IN THE INTERIOR. 12Z INL SOUNDING WAS ALSO QUITE DRY...WITH DEWPOINT DEPRESSIONS OF 20 TO 30C FROM 650MB TO 850MB. TONIGHT...UPPER LEVEL RIDGE AXIS IS PROGGED TO MOVE EAST TO THE DULUTH AREA BY 12Z...KEEPING UPPER MICHIGAN UNDER THE INFLUENCE OF HIGH PRESSURE. OTHER THAN SOME HIGH CLOUDS ENTERING THE U.P. LATE AS THE RIDGE AXIS NEARS...THE ENTIRE NIGHT SHOULD BE CLEAR. THE DRY AIR MASS (P.W. ON THE 12Z INL SOUNDING WAS 0.22 INCHES) COMBINED WITH THE CLEAR SKIES SHOULD ALLOW TEMPS TO EASILY FALL TO THE DEWPOINTS. FOLLOWED THE COOLER MAV GUIDANCE. MEANWHILE BACK TOWARDS THE WEST...THE SURFACE LOW OVER BILLINGS ENDS UP TURNING INTO THE DOMINANT LOW...MOVING OUT TO NW SOUTH DAKOTA AT 12Z MON. MONDAY...UPPER LEVEL TROUGH OVER THE PACIFIC MOVES INTO THE INTERMOUNTAIN WEST...RESULTING MORE PRESSURE FALLS OVER THE WESTERN HIGH PLAINS. THIS ALLOWS THE SURFACE LOW TO DEEPEN TO 993MB WITH A SLIGHT SOUTHWARD MOVEMENT TOWARDS RAPID CITY BY 00Z. CLOSER TO HOME...THE UPPER LEVEL RIDGE AXIS MOVES INTO WESTERN UPPER MICHIGAN...WHICH CAUSES THE SURFACE HIGH TO MOVE A LITTLE EASTWARD. WINDS WILL BE PICKING UP IN THE WESTERN U.P. OUT OF THE SE...PREVENTING LAKE BREEZES THERE. LAKE BREEZES WILL BE MORE COMMON ACROSS THE REST OF UPPER MICHIGAN THOUGH DUE TO LIGHTER WINDS. A TIGHT GRADIENT IN 850MB TEMPS IS PROGGED TO BE PRESENT AT 15Z (5C IN THE WEST COMPARED TO 0C IN THE EAST)...AND WITH THE LAKE BREEZES...A WIDE RANGE OF HIGH TEMPERATURES SHOULD EXIST. HIGH CLOUDS WILL BE INCREASING TOO THROUGH THE DAY...BUT THE COVERAGE REALLY DOES NOT INCREASE UNTIL LATE...SO THEY SHOULD NOT REDUCE MIXING THAT MUCH. WENT WITH HIGHS FROM 65 IN IWD (AIDED BY DOWNSLOPING) TO 53 IN ERY AND IN THE UPPER 40S FOR P59 AND ISQ. MONDAY NIGHT...DISCREPANCIES EXIST ON HOW FAR SOUTH THE SHRTWV AT THE BASE OF THE UPPER LEVEL TROUGH MOVES IN THE FOUR CORNERS REGION. THE GFS/NAM ARE NEARLY IDENTICAL HAVING THE SHRTWV MOVING INTO THE OKLAHOMA PANHANDLE AT 12Z TUE WITH THE ASSOCIATED SURFACE LOW MOVING SOUTH INTO NORTH CENTRAL KANSAS. THE CANADIAN/UKMET/ECMWF ARE FARTHER SOUTH IN EASTERN NEW MEXICO NEAR I-40. PER PMDHMD...AND THE TREND FOR THIS SYSTEM TO BE FARTHER SOUTH...WILL FOLLOW THE CANADIAN/UKMET/ECMWF. IN EITHER EVENT...THE UPPER LEVEL RIDGE AXIS WILL BE OVER UPPER MICHIGAN WITH BREEZY SOUTHEASTERLIES THROUGH THE NIGHT. THE ONLY CLOUD COVER LOOKS TO BE SOME HIGH CLOUDS SPREADING OVER TOP OF THE RIDGE. SO IT SHOULD BE A PARTLY CLOUDY NIGHT. WITH TEMPS ALREADY WARM AT THE START IN THE WEST AND DOWNSLOPING CONTINUING THROUGH THE NIGHT...DO NOT THINK TEMPS WILL FALL MUCH THERE. MET GUIDANCE FOR IWD IS 44...BUT WILL GO ABOVE THIS AS SIGNALS POINT TO EVEN A WARMER NIGHT. THE REST OF THE U.P. WILL SEE LOWS IN THE 30S...COLDEST EAST WHERE WINDS MAY HAVE A CHANCE TO DECOUPLE EARLY. TUESDAY THROUGH WEDNESDAY...CONTINUING TO FOLLOW THE CANADIAN/UKMET/ECMWF ON WHERE THE SHRTWV/ASSOCIATED SURFACE LOW TRACKS. DURING THE DAY TUESDAY...UPPER RIDGING BEGINS BUILDING AGAIN OVER THE WEST...CAUSING THE SHRTWV OVER THE OKLAHOMA PANHANDLE TO CLOSE OFF INTO AN UPPER LOW IN WESTERN OKLAHOMA. WITH THE STRONG RIDGE ALREADY OUT AHEAD OF IT...THE UPPER LOW WILL MOVE SLOWLY EAST...REACHING OKLAHOMA CITY AT 12Z WED AND FORT SMITH ARKANSAS AT 00Z THU. THE SURFACE LOW IS ALSO PROGGED TO TAKE A SIMILAR TRACK. THEREFORE LATE ON THE DAY ON TUESDAY...A COLD FRONTAL PASSAGE IS EXPECTED TO OCCUR...THEN PROGRESS SOUTHWARD TOWARDS MILWAUKEE BY WEDNESDAY EVENING. DEPENDING ON HOW MUCH MOISTURE IS ADVECTED INTO THE AREA ON TUESDAY...THERE IS THE POSSIBILITY OF SOME SURFACE BASED THUNDERSTORMS. WILL NEED TO WATCH THIS CLOSELY SINCE UPPER MICHIGAN WILL BE ON THE NOSE OF A THETA-E RIDGE AND TEMPERATURES SHOULD EASILY POP INTO THE MID 60S ALONG THE WISCONSIN BORDER (SINCE 850MB TEMPS ARE PROGGED AROUND 8C). SOME LINGERING STRATIFORM RAIN WILL HOLD BACK INTO UPPER MICHIGAN ON WEDNESDAY... AND WITH NE WINDS...MUCH COOLER CONDITIONS ARE IN STORE COMPARED TO TUESDAY. EXTENDED (THURSDAY THROUGH SUNDAY)...THE BIG QUESTION FOR THE END OF THE WEEK/WEEKEND WILL BE THE PROGRESS OF THE UPPER LOW. PREFER THE SLOWER IDEAS OF THE 00Z ECMWF/UKMET (WHICH THE 06Z GFS HAS BEEN TRENDING TOWARDS) BECAUSE OF THE SYSTEM IN THE SOUTHERN STREAM AND SINCE IT IS RUNNING INTO RIDGING OVER THE SOUTHEAST U.S.. AT 12Z THU...THE UPPER LOW IS PROGGED TO BE OVER WESTERN TENNESSEE AND THEN BY 12Z SAT OVER EASTERN VIRGINIA. WHAT THIS MEANS FOR UPPER MICHIGAN IS SOME LINGERING RAINFALL EARLY ON THU WITH THE BEST CHANCES IN THE SOUTHERN U.P....CLOSER TO THE UPPER LOW. THU ALSO LOOKS TO BE COOL WITH NE FLOW BETWEEN THE ASSOCIATED SURFACE LOW AND HIGH PRESSURE BUILDING SOUTH FROM ONTARIO. THIS HIGH WILL HELP TO DRY THINGS OUT FOR FRIDAY...BUT CONDITIONS APPEAR TO REMAIN COOL ALONG LAKE SUPERIOR WITH NE WINDS. INTERIOR SECTIONS SHOULD BE WARMER WITH 850MB TEMPS PROGGED BETWEEN 1 AND 3C. THE 00Z ECMWF AND 06Z GFS RUNS KEEP THE HIGH SITUATED OVER UPPER MICHIGAN THROUGH SUNDAY AS UPPER LEVEL RIDGING BUILDS AHEAD OF A TROUGH DEVELOPING OVER THE INTERMOUNTAIN WEST. SO THE WEEKEND SHOULD BE WARM AS 850MB TEMPS RISE TO 4 TO 6C ON SATURDAY AND 6 TO 8C ON SUNDAY. AT THE MOMENT I AM DISCOUNTING THE 00Z UKMET IDEA OF PHASING BETWEEN THE UPPER LOW AND A NORTHERN STREAM SHRTWV FRIDAY NIGHT...RESULTING IN A SOMEWHAT DEEP TROUGH OVER THE EASTERN PART OF THE COUNTRY. THE UKMET HAS BEEN TRENDING AWAY FROM THIS...ESPECIALLY THE 03/12Z RUN AND DOES NOT HAVE SUPPORT FROM ANY OF THE 00Z GFS ENSEMBLES...PLUS WITH THE SLOWER IDEA OF THE SOUTHERN STREAM UPPER LOW...THINK IT WILL MISS PHASING WITH NORTHERN STREAM SHRTWVS. && .MQT...WATCHES/WARNINGS/ADVISORIES...NONE. && $$ AJ mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 130 PM EDT SUN APR 3 2005 .AVIATION... VFR CIG/VIS THIS TAF PERIOD. WINDS CONTINUE TO BE STRONG AND GUSTY...WITH TIGHT PRESSURE GRADIENT BEHIND A PRETTY DEEP LOW MOVING ACROSS NEW YORK STATE. 12Z RUC/NAM CONTINUE TO SHOW DECENT WINDS PERSISTING ACROSS SOUTHEAST MICHIGAN THROUGH THE AFTERNOON. TAMDAR SOUNDINGS VICINITY OF DTW INDICATE MIXING UP TO 2-3KFT AGL...TAPPING INTO 35-40KTS OF THE 50-55KT LOW-LEVEL JET. GRADIENT WILL CONTINUE TO DIMINISH THROUGH THE DAY...ALREADY SEEN IN SOMEWHAT LIGHTER WINDS ACROSS THE SAGINAW VALLEY. WILL DROP WIND SPEEDS AND GUSTINESS AT TAF SITES THROUGH THE EVENING...ESPECIALLY OVERNIGHT AS WE LOSE THE DIURNAL MIXING. WIND SHEAR SHOULD NOT BE AN ISSUE TONIGHT AS THE LOW-LEVEL JET PULLS EAST AS WE START TO STABILIZE NEAR THE SURFACE. HIGH PRESSURE BUILDS ACROSS THE STATE ON MONDAY...ALLOWING WIND SPEEDS TO DROP EVEN FURTHER. && .SHORT TERM...TODAY AND TONIGHT...ISSUED AT 400 AM RESIDUAL AC HANGING ON ACROSS THE EASTERN PORTION OF THE CWA...BUT IR LOOP SHOWING SOME THINNING LAST COUPLE OF HOURS...SO LOOKS LIKE A MOSTLY SUNNY MORNING ACROSS THE ENTIRE CWA. ANOTHER BAND OF AC WORKING INTO THE WESTERN GREAT LAKES...BUT ANTICIPATE SOME EROSION OF THIS BAND AS WELL AS CONFLUENT UPPER FLOW STRENGTHENS OVER THE CENTRAL GREAT LAKES TODAY. SECONDARY UPPER WAVE WORKING INTO WESTERN ILLINOIS WILL ALSO CONTINUE TO DIVE SOUTHWEST OF THE CWA AND TAKING THE ASSOCIATED MID LEVEL CLOUD DECK WITH IT. UPPER LOW ALONG THE MIDDLE ATLANTIC SEABOARD WILL CONTINUE TO LIFT NORTHEAST TODAY...RESULTING IN INCREASING CONFLUENT UPPER FLOW OVER THE CENTRAL GREAT LAKES JUST EAST OF BUILDING UPPER RIDGE AXIS. SURFACE LOW OVER EASTERN PENNSYLVANIA SHOULD ALSO BEGIN TO FILL THIS AFTERNOON AS JET COUPLING WEAKENS...WHICH WILL RELAX SURFACE GRADIENT OVER THE CENTRAL GREAT LAKES. SO WILL TERMINATE GALE WARNING AROUND NOON FOR LAKE HURON AND LAKE ST CLAIR...BUT WILL HAVE TO CONTINUE WITH SMALL CRAFT ADVISORY FOR THE NEAR SHORE WATERS THROUGH THE AFTERNOON. MAY SEE A LITTLE AC THIS AFTERNOON AS WEAK VORTICITY AXIS SLIDES DOWN BACK SIDE OF UPPER RIDGE...HOWEVER MODELS HAVE BALLOONED 700 MB MOISTURE ASSOCIATED WITH THIS FEATURE AND WITH INCREASING CONFLUENT UPPER FLOW OVER THE CENTRAL GREAT LAKES ANTICIPATE JUST A BRIEF PERIOD OF SCATTERED AC FROM AROUND 20-03Z. MODELS IN GENERAL AGREEMENT OVER THE CENTRAL GREAT LAKES IN THE SHORT TERM...HOWEVER THE GFS HAS A BETTER HANDLE ON 850 MB TEMPS OVER THE WESTERN GREAT LAKES...SO WILL LEAN TOWARD SLIGHTLY COOLER MAV TEMPS FOR THIS AFTERNOON. IN ADDITION DEEP MIXED LAYER AND STRONG NORTH WINDS WILL ALSO KEEP TEMPS DOWN A LITTLE. RIDGE AXIS TO BUILD IN OVERNIGHT...AND LOW RH AIR MASS IN PLACE...SO RADIATIONAL COOLING POTENTIAL WILL BE GOOD...WILL TRIM LOWS BACK A DEGREE OR TWO. && .LONG TERM...MONDAY THROUGH SATURDAY...ISSUED AT 400 AM PRETTY MINOR ISSUES FOR MOST OF THE LONG TERM FORECAST... ESPECIALLY FOR MONDAY... TUESDAY TIME FRAME. MODELS GENERALLY SHOWING GOOD CONTINUITY ON RETREATING SYSTEM TO THE EAST AND DEVELOPING SYSTEM TO THE WEST. NAM IS NOW MUCH STRONGER THAN PREVIOUS RUNS ON DEVELOPING LOW OVER KANSAS BY 60 HOURS. GFS IS A LITTLE BROADER WITH THE CIRCULATION AND TENDS TO CLEAR THE RIDGE OUT OF THE GREAT LAKES PROBABLY A LITTLE FAST GIVEN THE RAPID CLOSING OF THE UPPER LOW AND OVERALL AMPLIFICATION OF THE LARGE SCALE PATTERN. PREFER THE NAM IN THIS REGARD... KEEPING CLOUDS AND RETURN FLOW MORE AT BAY INTO MID WEEK. FOR WEDNESDAY EXPECTING THE UPPER LOW TO AT LEAST MIGRATE TO THE MID MISSISSIPPI VALLEY BRINGING WIDESPREAD CLOUD COVER TO THE REGION AND SOME ORGANIZED PRECIPITATION. WILL KEEP CHANCE OF THUNDER GOING FOR THE MOST OF THE CWA... WITH THE EXCEPTION OF CENTRAL AND NORTHERN LAKE HURON. HAVE RAISED POPS IN THAT TIME FRAME IN ALL AREAS. AS PER HPC MODEL DISCUSSION... FEEL GFS IS A LITTLE TOO FAR NORTH ON THE LOW POSITION ON WEDNESDAY (EASTERN IOWA) BEFORE IT DIVES BACK TOWARD THE SOUTHEAST. CONFIDENCE IN THE GFS AFTER 90 HRS IS A LITTLE SHAKY RIGHT NOW BASED ON WIDELY VARIANT RUN-TO-RUN LONGER RANGE SOLUTIONS. HAVE INTRODUCED SOME ASPECTS OF THE LATEST TREND INTO THE FORECAST... BUT SLOWED THE EVOLUTION QUITE A BIT TO ACCOUNT FOR THE UNCERTAINTY. TEMPERATURES...WILL CONTINUE COOLER ALONG THE LAKESHORE GRID DEPICTION WITH AN EXTENDED PERIOD OF SOUTHEASTERLY OR LIGHT SOUTHEAST FLOW THROUGH MID WEEK. AWAY FROM THE LAKE THOUGH... TEMPS SHOULD BE FAIRLY MILD WITH A FAIR AMOUNT OF SUNSHINE MONDAY AND TUESDAY. MODELS ARE VERY DRY THROUGH THE COLUMN... SO CUT BACK SUBSTANTIALLY IN THE CLOUD COVER FORECAST UNTIL WEDNESDAY. && .DTX WATCHES/WARNINGS/ADVISORIES... .MI...NONE. .LAKE HURON... GALE WARNING...FOR THE SOUTH HALF...THROUGH THIS EVENING. SMALL CRAFT ADVISORY...ALL NEARSHORE WATERS...THROUGH THIS EVENING. .LAKE ST CLAIR...GALE WARNING...THIS AFTERNOON. .MI WATERS OF LAKE ERIE...SMALL CRAFT ADVISORY...THROUGH THIS EVENING. $$ BRAVENDER/GSS/WAG mi