AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE PEACHTREE CITY GA 945 PM EDT THU JUN 2 2005 .DISCUSSION... UPPER LOW...THAT HAS PLAGUED THE AREA THIS ENTIRE WEEK...LIFTING SLOWLY NORTH THROUGH NORTHERN AL INTO TN. THE LOW WILL CONTINUE TO LIFT NORTH THROUGH FRIDAY. WEAK FRONT REMAINS ACROSS CENTRAL GA...WITH A PERSISTENT COOL...WEDGE LIKE AIR MASS IN PLACE ACROSS THE N-NE PART OF THE STATE. THIS FRONT HAS OSCILLATED BACK AND FORTH OVER THE PAST COUPLE OF DAYS...BUT HAS NEVER MADE IT MUCH FURTHER NORTH THAN ATL. THE FRONT DRIFTED BACK TO THE SOUTH AGAIN THIS EVENING TO NEAR CSG-MCN. EXPECT THE FRONT TO REMAIN NEARLY STATIONARY OVERNIGHT...THEN DRIFT NORTH IN EARNEST FRIDAY AS THE UPPER LOW LIFTS NORTH. WE SHOULD FINALLY BE DONE WITH IT AT THAT POINT. SUPPORT FOR SHRA/TSRA ACTIVITY CERTAINLY LESS FRIDAY THAN WE HAVE SEEN IN MANY DAYS. MID-LEVELS DRY OUT AND DEWPOINTS RISE AS LOW-LEVEL RESIDUAL COOL AIR MASS OVER N GA IS FINALLY SCOURED OUT. LOOKS LIKE THE AREA WILL FINALLY GET INTO A MORE SUMMERLIKE AIR MASS...AND EVEN MORE SO ON SATURDAY WITH DEWPOINTS 70-72 AS FAR NORTH AS ATL. IT WILL FEEL AWFULLY WARM AND STEAMY AFTER THE UNSEASONABLY COOL...DAMP CONDITIONS OF THE PAST FEW DAYS. FOR THE UPCOMING WEEK...BUT ESPECIALLY THE SHORT TERM...OVERALL UPPER SUPPORT IS WEAK AS UPPER RIDGE BUILDS IN FROM THE WESTERN ATLANTIC. HOWEVER...WEAK DISTURBANCES WILL CONTINUE TO RIDE FROM A SW U.S. UPPER LOW TOWARD THE OHIO VALLEY...WITH TRAILING TROUGHS AFFECTING THE SE U.S. WITH A WARM...HUMID AIR MASS IN PLACE...EXPECT AT A MINIMUM DIURNALLY DRIVEN CONVECTION EACH DAY. BY THE END OF THE WEEK...CLOSED UPPER RIDGE EVOLVES OVER THE MID-ATLANTIC/NC AREA...WITH LOW PRESSURE IN THE EASTERN GULF...WITH THE HINT OF A POSSIBLE TROPICAL SYSTEM POISED TO MOVE NORTH INTO THE SE U.S. IT SUFFICES TO SAY...THAT THE NEXT WEEK OR SO WILL OVERALL BE WET AND HUMID WITH GOOD CHANCES OF SHRA/TSRA MOST DAYS. TEMPERATURES WILL FINALLY RISE TO NEAR SEASONAL LEVELS FRIDAY...AND SHOULD REMAIN THERE THROUGH THE UPCOMING WEEK. && .UPDATE... GFS MODEL HANDLED CONVECTION THE BEST TODAY...AND WAS REALLY THE ONLY MODEL TO PROPERLY DEPICT EVOLUTION OF CONVECTION FROM S AL INTO CENTRAL GA AS IT OCCURRED. ETA HAS OVERALL BEEN FAIRLY POOR WITH DEPICTION OF PRECIPITATION AREAS. GOOD 850MB AND UPPER JET OVER THE AREA COMBINED WITH A POCKET OF COLD AIR ALOFT...-12C AT 500MB...PROVIDED FOR THE SEVERE CONVECTION OBSERVED THIS AFTERNOON/EVENING. WEAK FRONTAL BOUNDARY WILL CONTINUE TO SERVE AS A FOCUS FOR ADDITIONAL SHRA/TSRA OVERNIGHT AS BEST DYNAMICS AND SUPPORT LIFT INTO N GA OVERNIGHT. HAVE LOWERED POPS TO JUST CHANCE CATEGORY OVER THE SW PART OF THE AREA...WITH LIKELY POPS REMAINING IN THE N CENTRAL/NE. THUNDER THREAT WILL DIMINISH OVERNIGHT...BUT SOME HEAVY RAIN STILL POSSIBLE. AFTER CONSIDERABLE CONSTERNATION EARLIER...HAVE DECIDED AGAINST ISSUING A FLOOD WATCH AT THIS TIME. DYNAMICS WILL BE QUITE WEAK ON FRIDAY...BUT AMPLE INSTABILITY SHOULD BE IN PLACE WITH BETTER HEATING. POPS LOOK A LITTLE HIGH BASED ON MODEL MOISTURE PROGS/MOS GUIDANCE. LOWERED TEMPERATURES SLIGHTLY IN THE NORTH TO ACCOUNT FOR PERSISTENCE WEDGE...OTHERWISE LITTLE CHANGE MADE. MINOR CHANGES MADE TO SKY AND WIND GRIDS FOR THE FIRST TWO PERIODS. && .AVIATION...APPEARS FRONT JUST S OF FFC AND CONVECTION CONTINUES SOUTH OF THE FRONT. QUESTION WILL BE WHETHER THE FRONT WILL LIFT FAR ENOUGH NORTH DURING THE EVENING TO PUT N GA IN THE MORE UNSTABLE AIR. RUC SHOWS FRONT NEARLY STALLED JUST S OF ATL. AREA OF TRW OVER NE AL DOES NOT APPEAR TO BE MAKING MUCH PROGRESS EASTWARD. BOTTOM LINE IS PROBABLY JUST A CHANCE OF SHOWERS AROUND ATL DURING THE EVENING WITH CIGS BETWEEN 15-25 HND FT BUT CIGS AGAIN BLO 1 THSD FT AFTER MIDNIGHT. THESE LOW CIGS SHOULD STAY IN UNTIL AROUND 15Z FRI. WINDS MAINLY EASTERLY 8-10 KTS THIS EVENING...BUT COULD GET MORE VARIABLE AROUND HEAVY SHOWERS. THEY WILL BE GOING INTO THE SOUTHWEST FRIDAY MORNING...PROBABLY AFTER THE LOW CLOUDS LIFT AND WE GET SOME MIXING. && .PRELIMINARY POINT TEMPS/POPS... ATLANTA 62 76 65 84 / 70 40 20 30 ATHENS 62 76 65 87 / 70 50 30 20 GAINESVILLE 59 73 63 84 / 70 50 30 20 ROME 63 79 66 87 / 60 40 30 30 COLUMBUS 66 84 68 89 / 60 40 5 30 MACON 67 84 67 90 / 60 40 5 30 && .FFC WATCHES/WARNINGS/ADVISORIES... GA...NONE. && $$ RAB/JRN ga AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE PEACHTREE CITY GA 530 PM EDT THU JUN 2 2005 .SHORT TERM... WEDGE HOLDING ACROSS NORTH GEORGIA TODAY STILL EXPECTED TO WEAKEN AND SCOUR OUT AS THE FRONTAL BOUNDARY STRETCHING ACROSS CENTRAL GEORGIA BEGINS TO LIFT NORTHWARD ACROSS THE AREA LATE TONIGHT INTO FRIDAY. WATCHING AREA OF SHOWERS/TSTORMS DEVELOPING ACROSS SOUTHERN ALABAMA AT THE MOMENT. EXPECT THIS AREA TO SPREAD NORTHEAST AFFECTING MUCH OF OUR COUNTY WARNING AREA THIS AFTERNOON INTO TONIGHT. CURRENT FORECAST WITH GOOD CHANCE TO LIKELY POPS STILL LOOK OKAY. MODELS INDICATING SOME DRIER AIR WORKING INTO THE AREA FROM THE SOUTHWEST FRIDAY AFTERNOON AS BOUNDARY CONTINUES TO LIFT NORTHWARD. WILL SEE A RETURN TO A MORE SUMMERTIME CONVECTION PATTERN FRIDAY AFTERNOON INTO THE WEEKEND AS WEAK RIDGE BUILDS ACROSS THE AREA. LOW CHANCE POPS AND WARMER TEMPS LOOK TO BE THE RULE. .LONG TERM... WEAK UPPER RIDGE CONTINUES OVER THE AREA MONDAY. EXTENDED MODELS SIMILAR WITH WEAK UPPER TROF PUSHING ACROSS OUR AREA TUESDAY/ WEDNESDAY TIME FRAME...WITH ASSOCIATED WEAK FRONT BACK DOORING INTO NORTH GEORGIA WEDNESDAY/THURSDAY. ALL IN ALL...UNSETTLED WEATHER PATTERN IN THE CARDS AND BEST BET SEEMS TO CONTINUE LOW CHANCE POPS THROUGH THE PERIOD. && .AVIATION...APPEARS FRONT JUST S OF FFC AND CONVECTION CONTINUES SOUTH OF THE FRONT. QUESTION WILL BE WHETHER THE FRONT WILL LIFT FAR ENOUGH NORTH DURING THE EVENING TO PUT N GA IN THE MORE UNSTABLE AIR. RUC SHOWS FRONT NEARLY STALLED JUST S OF ATL. AREA OF TRW OVER NE AL DOES NOT APPEAR TO BE MAKING MUCH PROGRESS EASTWARD. BOTTOM LINE IS PROBABLY JUST A CHANCE OF SHOWERS AROUND ATL DURING THE EVENING WITH CIGS BETWEEN 15-25 HND FT BUT CIGS AGAIN BLO 1 THSD FT AFTER MIDNIGHT. THESE LOW CIGS SHOULD STAY IN UNTIL AROUND 15Z FRI. WINDS MAINLY EASTERLY 8-10 KTS THIS EVENING...BUT COULD GET MORE VARIABLE AROUND HEAVY SHOWERS. THEY WILL BE GOING INTO THE SOUTHWEST FRIDAY MORNING...PROBABLY AFTER THE LOW CLOUDS LIFT AND WE GET SOME MIXING. && .PRELIMINARY POINT TEMPS/POPS... ATLANTA 62 76 65 84 / 70 40 20 30 ATHENS 62 76 65 87 / 70 50 30 20 GAINESVILLE 59 73 63 84 / 70 50 30 20 ROME 63 79 66 87 / 60 40 30 30 COLUMBUS 66 84 68 89 / 60 40 5 30 MACON 67 84 67 90 / 60 40 5 30 && .FFC WATCHES/WARNINGS/ADVISORIES... GA...NONE. && $$ 27 ga AREA FORECAST DISCUSSION...CORRECTED HEADERS NATIONAL WEATHER SERVICE LINCOLN IL 1000 AM CDT THU JUN 2 2005 .DISCUSSION... MOISTURE CONTINUES TO STREAM NORTH INTO EASTERN FORECAST AREA AHEAD OF SLOW MOVING UPPER LOW OVER MIDDLE MISSISSIPPI VALLEY. LAMP GUIDANCE AND 12Z HIGH RES ETA BOTH INDICATE THAT CURRENT PACKAGE IS A BIT TOO OPTIMISTIC ON CLEARING AND TEMPERATURES TODAY IN THIS REGION WITH TEMPERATURES CURRENTLY STRUGGLING TO CLIMB THROUGH THE 60S. WILL ADJUST TEMPS DOWN...ENHANCE CLOUD COVER...AND INCREASE POPS FROM I-55 EAST. && .PREV DISCUSSION... FORECAST CHALLENGE IS HOW FAR NW RAIN CHANCES GET TODAY AND TONIGHT AS MID LEVEL DISTURBANCE NEAR TN/MS WEAKENS AND LIFTS NE INTO THE UPPER OHIO VALLEY FRI. SHORT RANGE MODELS HAVE BEEN TRENDING QPF FURTHER NW ACROSS IL TODAY WITH GFS AND NAM HAVING QPF AS FAR WEST AS THE IL RIVER WHILE CANADIAN HAS LIGHT QPF WEST TO THE MS RIVER. RUC THROUGH 18Z HAS QPF ACROSS EASTERN IL EAST OF I-55 AND WILL TEND TO FOLLOW THIS ROUTE. SHORT TERM...TODAY THROUGH FRIDAY NIGHT... RADAR MOSAIC SHOWS LIGHT RETURNS ALONG AND EAST OF A RANTOUL TO TAYLORVILLE LINE WHILE GROUND TRUTH REPORTS OF LIGHT RAIN MAINLY ALONG AND SE OF I-70. ELONGATED MID LEVEL LOW WAS OVER THE MID MS VALLEY. SURFACE MAP HAS 1007 MB LOW PRESSURE OVER FAR NORTHERN MS WITH A TROF OF LOW PRESSURE EXTENDING INTO CENTRAL INDIANA. 1025 MB HIGH PRESSURE WAS OFF THE NEW ENGLAND COAST AND RIDGING WESTWARD ACROSS THE GREAT LAKES. MORE CLOUD COVER EARLY THIS MORNING ESPECIALLY EAST OF THE IL RIVER KEEPING TEMPS MILDER TO START THE DAY...IN THE LOWER 60S. DEWPOINTS RANGE FROM THE LOWER 50S NORTH OF I-74 TO THE LOWER 60S FROM TAYLORVILLE AND MATTOON SOUTH. MID LEVEL LOW TO OPEN UP INTO AN UPPER LEVEL TROF AND LIFT NE INTO THE UPPER OHIO VALLEY FRI WHILE SURFACE LOW NEAR TN/MS BORDER EVOLVES INTO A TROF OF LOW PRESSURE ACROSS KY/TN. ISENTROPIC LIFT AFFECTS AREAS MAINLY EAST OF I-55 TODAY AND THAT IS WHERE CHANCE OF LIGHT SHOWERS WILL BE WITH HIGHEST CHANCES NEAR THE WABASH RIVER. ISOLATED THUNDERSTORMS POSSIBLE FROM LAWRENCEVILLE SE TODAY. MORE CLOUDS TODAY KEEPS TEMPS COOLER ESPECIALLY SE IL WITH HIGHS IN THE LOWER 70S. GUIDANCE CONTINUES TO COOL AND NOW AS COOL AS 66 BY LAWRENCEVILLE WHICH SEEMS TOO COOL FOR EARLY JUNE. HAVE SLIGHT CHANCE OF SHOWERS OVER FAR EASTERN IL TONIGHT WHILE CHANCE POPS JUST EAST OVER INDIANA AS SOME MOISTURE LINGERS WITH UPPER LEVEL TROF NEARBY. SHOULD SEE DECREASING CLOUDS FROM WEST TO EAST FRI AS SKIES BECOME PARTLY SUNNY AS UPPER LEVEL TROF LIFTS INTO THE UPPER OHIO VALLEY. WARMER HIGHS IN THE UPPER 70S EAST AND LOWER 80S WEST. NEARLY A 10 DEGREE DIFFERENCE FROM WARMER FWC HIGHS AND COOLER MAV HIGHS AND WENT IN BETWEEN CLOSER TO MET. FRI SHOULD STAY DRY AS UPPER LEVEL RIDGE BUILDING INTO IL. LOW PRESSURE OVER THE PLAINS TO LIFT A WARM FRONT NORTH INTO CENTRAL IL FRI NIGHT BRINING A CHANCE OF CONVECTION TO WESTERN AREAS AND SLIGHT CHANCE EAST. LONG TERM...SATURDAY THROUGH WEDNESDAY... WARMER AND MORE HUMID SAT AS WARM FRONT LIFTS NORTH OF CENTRAL IL AND IN SOUTHERLY FLOW. WILL FEEL MORE LIKE FLORIDA WEATHER WITH HIGHS IN THE 80S AND DEWPOINTS INTO THE 60S. CHANCE OF CONVECTION ESPECIALLY AFTERNOON WEST OF I-55 WHERE SPC HAS A SLIGHT RISK OF SEVERE STORMS. CONTINUED CONVECTION CHANCES SUNDAY/MONDAY AS FRONTAL BOUNDARY MOVES SE THROUGH IL MON. GULF OPEN FOR A COUPLE DAYS SHOULD ALLOW DEEPER MOISTURE TO WORK INTO IL FOR FRONTAL BOUNDARY AND SHORT WAVES IN SW UPPER LEVEL FLOW TO INTERACT WITH AND BRING BEST CHANCES OF RAIN TO CENTRAL AND SE IL SINCE MAY 19. STILL COULD BE A SLIGHT CHANCE OF CONVECTION AFTER MONDAY AS EXTENDED MODELS DIFFER WITH POSITION OF HOW FAR FRONTAL BOUNDARY GETS SE. && .ILX WATCHES/WARNINGS/ADVISORIES... IL...NONE. $$ BARKER/HUETTL il AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LINCOLN IL 1000 AM CDT THU JUN 2 2005 .PREV DISCUSSION... MOISTURE CONTINUES TO STREAM NORTH INTO EASTERN FORECAST AREA AHEAD OF SLOW MOVING UPPER LOW OVER MIDDLE MISSISSIPPI VALLEY. LAMP GUIDANCE AND 12Z HIGH RES ETA BOTH INDICATE THAT CURRENT PACKAGE IS A BIT TOO OPTIMISTIC ON CLEARING AND TEMPERATURES TODAY IN THIS REGION WITH TEMPERATURES CURRENTLY STRUGGLING TO CLIMB THROUGH THE 60S. WILL ADJUST TEMPS DOWN...ENHANCE CLOUD COVER...AND INCREASE POPS FROM I-55 EAST. && .DISCUSSION... FORECAST CHALLENGE IS HOW FAR NW RAIN CHANCES GET TODAY AND TONIGHT AS MID LEVEL DISTURBANCE NEAR TN/MS WEAKENS AND LIFTS NE INTO THE UPPER OHIO VALLEY FRI. SHORT RANGE MODELS HAVE BEEN TRENDING QPF FURTHER NW ACROSS IL TODAY WITH GFS AND NAM HAVING QPF AS FAR WEST AS THE IL RIVER WHILE CANADIAN HAS LIGHT QPF WEST TO THE MS RIVER. RUC THROUGH 18Z HAS QPF ACROSS EASTERN IL EAST OF I-55 AND WILL TEND TO FOLLOW THIS ROUTE. SHORT TERM...TODAY THROUGH FRIDAY NIGHT... RADAR MOSAIC SHOWS LIGHT RETURNS ALONG AND EAST OF A RANTOUL TO TAYLORVILLE LINE WHILE GROUND TRUTH REPORTS OF LIGHT RAIN MAINLY ALONG AND SE OF I-70. ELONGATED MID LEVEL LOW WAS OVER THE MID MS VALLEY. SURFACE MAP HAS 1007 MB LOW PRESSURE OVER FAR NORTHERN MS WITH A TROF OF LOW PRESSURE EXTENDING INTO CENTRAL INDIANA. 1025 MB HIGH PRESSURE WAS OFF THE NEW ENGLAND COAST AND RIDGING WESTWARD ACROSS THE GREAT LAKES. MORE CLOUD COVER EARLY THIS MORNING ESPECIALLY EAST OF THE IL RIVER KEEPING TEMPS MILDER TO START THE DAY...IN THE LOWER 60S. DEWPOINTS RANGE FROM THE LOWER 50S NORTH OF I-74 TO THE LOWER 60S FROM TAYLORVILLE AND MATTOON SOUTH. MID LEVEL LOW TO OPEN UP INTO AN UPPER LEVEL TROF AND LIFT NE INTO THE UPPER OHIO VALLEY FRI WHILE SURFACE LOW NEAR TN/MS BORDER EVOLVES INTO A TROF OF LOW PRESSURE ACROSS KY/TN. ISENTROPIC LIFT AFFECTS AREAS MAINLY EAST OF I-55 TODAY AND THAT IS WHERE CHANCE OF LIGHT SHOWERS WILL BE WITH HIGHEST CHANCES NEAR THE WABASH RIVER. ISOLATED THUNDERSTORMS POSSIBLE FROM LAWRENCEVILLE SE TODAY. MORE CLOUDS TODAY KEEPS TEMPS COOLER ESPECIALLY SE IL WITH HIGHS IN THE LOWER 70S. GUIDANCE CONTINUES TO COOL AND NOW AS COOL AS 66 BY LAWRENCEVILLE WHICH SEEMS TOO COOL FOR EARLY JUNE. HAVE SLIGHT CHANCE OF SHOWERS OVER FAR EASTERN IL TONIGHT WHILE CHANCE POPS JUST EAST OVER INDIANA AS SOME MOISTURE LINGERS WITH UPPER LEVEL TROF NEARBY. SHOULD SEE DECREASING CLOUDS FROM WEST TO EAST FRI AS SKIES BECOME PARTLY SUNNY AS UPPER LEVEL TROF LIFTS INTO THE UPPER OHIO VALLEY. WARMER HIGHS IN THE UPPER 70S EAST AND LOWER 80S WEST. NEARLY A 10 DEGREE DIFFERENCE FROM WARMER FWC HIGHS AND COOLER MAV HIGHS AND WENT IN BETWEEN CLOSER TO MET. FRI SHOULD STAY DRY AS UPPER LEVEL RIDGE BUILDING INTO IL. LOW PRESSURE OVER THE PLAINS TO LIFT A WARM FRONT NORTH INTO CENTRAL IL FRI NIGHT BRINING A CHANCE OF CONVECTION TO WESTERN AREAS AND SLIGHT CHANCE EAST. LONG TERM...SATURDAY THROUGH WEDNESDAY... WARMER AND MORE HUMID SAT AS WARM FRONT LIFTS NORTH OF CENTRAL IL AND IN SOUTHERLY FLOW. WILL FEEL MORE LIKE FLORIDA WEATHER WITH HIGHS IN THE 80S AND DEWPOINTS INTO THE 60S. CHANCE OF CONVECTION ESPECIALLY AFTERNOON WEST OF I-55 WHERE SPC HAS A SLIGHT RISK OF SEVERE STORMS. CONTINUED CONVECTION CHANCES SUNDAY/MONDAY AS FRONTAL BOUNDARY MOVES SE THROUGH IL MON. GULF OPEN FOR A COUPLE DAYS SHOULD ALLOW DEEPER MOISTURE TO WORK INTO IL FOR FRONTAL BOUNDARY AND SHORT WAVES IN SW UPPER LEVEL FLOW TO INTERACT WITH AND BRING BEST CHANCES OF RAIN TO CENTRAL AND SE IL SINCE MAY 19. STILL COULD BE A SLIGHT CHANCE OF CONVECTION AFTER MONDAY AS EXTENDED MODELS DIFFER WITH POSITION OF HOW FAR FRONTAL BOUNDARY GETS SE. && .ILX WATCHES/WARNINGS/ADVISORIES... IL...NONE. $$ BARKER/HUETTL il AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GOODLAND KS 211 PM MDT THU JUN 2 2005 .SHORT TERM... (TONIGHT-SUNDAY) WATER VAPOR SHOWS LARGE CUT OFF SYSTEM SPINNING OVER SOUTHERN SASKATCHEWAN. FAST FLOW ON SOUTHERN PERIPHERY WITH EMBEDDED SHORTWAVE OVER NORTHERN UTAH THIS MORNING WILL ROTATE ACROSS NORTHERN PLAINS TONIGHT...WITH FORECAST AREA ON SOUTHERN FRINGE OF ASSOCIATED FORCING. OVERNIGHT MCS LAID DOWN AN OUTFLOW BOUNDARY WHICH AT 18Z WAS LOCATED ROUGHLY FROM LAMAR COLORADO TO HILL CITY. NORTH OF THE BOUNDARY LOW CLOUDS HAVE BEEN SLOW TO ERODE IN KANSAS AND NEBRASKA WITH THE NORTHEASTERLY SURFACE WINDS. HOWEVER CLEARING WAS NOTED OVER NORTHEAST COLORADO AND RUCII INSISTS ON AT LEAST PARTIAL CLEARING BY THE AFTERNOON OVER THE ENTIRE AREA. ASSUMING SURFACE HEATING DOES OCCUR...ATMOSPHERE WILL BECOME VERY UNSTABLE WITH CAPE APPROACHING 4000 J/KG. 0-6KM BULK SHEAR VALUES WILL BE AROUND 40KTS. MOST LIKELY SCENARIO WILL BE FOR CONVECTIVE INITIATION TO OCCUR OVER NORTHEASTERN COLORADO THIS AFTERNOON WITH APPROACH OF MID LEVEL FORCING...SPREADING EASTWARD THIS EVENING INTO THE FORECAST AREA. OTHER STORMS MAY FIRE ON THE OUTFLOW BOUNDARY NEAR EASTERN AND SOUTHERN ZONES. A FEW SUPERCELLS LIKELY GIVEN SHEAR AND INSTABILITY...THEN EVOLVING INTO AND OVERNIGHT MCS. FRIDAY...SYNOPTIC SITUATION CHANGES VERY LITTLE OWING TO SLOW MOVEMENT OF CUT OFF LOW TO THE NORTH. ANOTHER STRONG SHORTWAVE FORECAST TO MOVE ACROSS THE FORECAST AREA IN THE AFTERNOON AND EVENING. SURFACE FRONT WILL ARC FROM NORTH CENTRAL TO SOUTHWEST KANSAS THEN NORTH INTO EAST CENTRAL COLORADO. STORMS LIKELY TO INITIATE ALONG THE FRONT WITH APPROACHING SHORTWAVE...THEN MOVE EAST INTO THE FORECAST AREA DURING THE EVENING. ENVIRONMENT AHEAD OF THE STORMS WILL BE UNSTABLE WITH CAPE VALUES FORECAST 1000-2000 J/KG AND BULK SHEAR AGAIN NEAR 40KTS. EXPECT ANOTHER ROUND OF SEVERE STORMS. SATURDAY/SUNDAY...FORECAST AREA TO REMAIN UNDER FAST SOUTHWEST FLOW ALOFT. ANOTHER SHORTWAVE WILL BE MOVING THROUGH SATURDAY AFTERNOON AND EVENING. TIMING DIFFERENCES EXIST AMONG THE SHORT RANGE MODELS WITH THAT FEATURE. AFTER TWO DAYS OF CONVECTION MESOSCALE DETAILS VERY DIFFICULT TO FORECAST AT THIS POINT AS WELL. BETTER UPPER SUPPORT ON SATURDAY WARRANTS CHANCE POPS...BUT WILL HOLD OFF ON SUNDAY FOR NOW WITH WARMING MID LEVEL TEMPERATURES AND SHORTWAVE ENERGY SOUTH/WEST OF THE AREA. .LONG TERM... (MONDAY-THURSDAY) GENERAL UPPER PATTERN WILL FEATURE CUT OFF UPPER LOW OVER THE PACIFIC NORTHWEST WHICH WILL VERY SLOWLY MAKES ITS WAY ACROSS THE NORTHERN ROCKIES AND EVENTUALLY EJECT INTO THE NORTHERN PLAINS BY THE END OF THE PERIOD. LARGE TROUGH WILL BE CARVED OUT ACROSS THE WESTERN CONUS. UPPER RIDGING AND SOUTHWEST FLOW AHEAD OF THE SYSTEM WILL RESULT IN WARM CONDITIONS FOR THE FORECAST AREA MONDAY AND TUESDAY. UPPER HEIGHT FALLS WILL BEGIN OVER THE CENTRAL ROCKIES MONDAY NIGHT AND SPREAD EASTWARD ON TUESDAY. THIS WILL SUPPORT LEE CYCLOGENESIS OVER EASTERN COLORADO. BEST SYNOPTIC SCALE FORCING WILL STAY WELL TO THE NORTH...WHILE BEST MOISTURE WILL BE TO THE EAST. MONDAY APPEARS TO BE THE BETTER DAY FOR CONVECTION BASED ON LOW LEVEL MOISTURE...BUT TOUGH TO FIND INITIATING MECHANISM OTHER THAN SURFACE HEATING NEAR LEE TROUGH IN COLORADO. TUESDAY THE SURFACE LOW WILL BE A LITTLE FURTHER EAST...AND CONVECTION LIKELY TO DEVELOP ALONG SHARPENING DRY LINE. TOUGH CALL ON WHERE THAT DRY LINE WILL BE LOCATED...BUT ENOUGH UNCERTAINTY TO MENTION THUNDERSTORMS EASTERN HALF. GFS ADVERTISING A COLD FRONT ON WEDNESDAY...BUT THE ECMWF KEEPS THE AREA UNDER WARM RIDGING ALOFT. SAME DISCREPANCIES LIKELY TO CARRY INTO THURSDAY. WILL AVERAGE OUT THE 850MB TEMPERATURES TO DERIVE SURFACE HIGH TEMPERATURES. NOT ENOUGH CONFIDENCE IN EITHER MODEL SOLUTION FOR MORE THAN A SILENT 10 POP AT THIS POINT. && .GLD WATCHES/WARNINGS/ADVISORIES... .KS...NONE. .NE...NONE. .CO...NONE. && $$ JDK ks AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 425 PM EDT THU JUN 2 2005 .DISCUSSION... MAIN FCST CONCERNS ARE SHRA/TSRA POTENTIAL/TIMING SAT THROUGH MON. WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROF OVER SRN SASK EXTENDING INTO INTO THE NRN ROCKIES WITH A DOWNSTREAM RDG OVER THE GREAT LAKES. SRN STREAM VORTS WERE LOCATED OVER THE BAJA AND WRN TEN. AT THE SFC...ACYC SSE FLOW PREVAILED OVER MOST OF THE AREA. SUNSHINE WITH STRONG MIXING HAS PUSHED DEWPOINTS INTO THE LOWER 40S OVER MUCH OF THE AREA. VIS LOOP SHOWED MAIN CLEAR SKIES WITH CU FIELD TOUCHING THE FAR WEST AND CI BAND SHIFTING INTO FAR E UPR MI. TONIGHT...ALTHOUGH SOME CI MAY SPREAD INTO W UPR MI...PER SATELLITE TRENDS AND NAM 400 RH PROG...SKIES SHOULD REMAIN MAINLY CLEAR OVER THE REST OF UPR MI. A TIGHTER GRADIENT OVER THE W WITH DOWNSLOPE FLOW SHOULD KEEP TEMPS FROM DROPPING OFF TOO MUCH. HOWEVER...OVER THE CNTRL AND EAST...LIGHT WINDS AND DRY AIR SHOULD ALLOW TEMPS TO FALL AOB GUIDANCE VALUES WITH INLAND READINGS IN THE MID TO UPPER 40S. FRI...MDLS ARE CONSISTENT IN KEEPING MID LEVEL RDG FIRMLY IN CONTROL WITH MID LEVEL DRYING AND SUBSIDENCE INVERSION BTWN 700-600 MB KEEPING DRY WEATHER GOING. SIMILAR TO TODAY...LITTLE IN THE WAY OF CU EXPECTED WITH MAINLY THIN HIGH CLOUDS OVER UPR MI. WITH SIMILAR 850 MB TEMPS FCST AS THU (13C-14C)...PERSISTENCE SUGGESTS MAX TEMPS SHOULD ALSO CLIMB AOA GUIDANCE VALUES WITH SOME LOW 80S AGAIN OVER INLAND AREAS AND ONLY SLIGHT INLAND MODIFICATION OFF OF LK SUPERIOR OVER N CNTRL UPR MI. FRI NIGHT INTO SAT NIGHT...FCST TRENDED TOWARD THE 12Z GFS/UKMET/CANADIAN RATHER THAN THE 12Z NAM. OUTLIER NAM PROPAGATION OF THE BAJA VORT EASTWARD...COMPARED TO GLBL MDLS ABSORPTION INTO THE NRN PLAINS LOW(PER HPC DISC)...SEEMS TO ALLOW MORE PROGRESSIVE MID LVL TREND WITH SHRTWV FROM NRN UT AND ASSOCIATED ISENTROPIC LIFT AHEAD OF THE WARM FRONT BRINGING AREA OF PCPN THROUGH UPR MI LATE FRI NIGHT INTO SAT. THE GFS/UKMET WITH A MORE PROMINENT MID LEVEL RDG WOULD DELAY PCPN TO MAINLY LATER SAT AFTERNOON OR SAT NIGHT WHEN STRONGER QVECTOR CONV (UPR LVL DIFFLUENCE/DIV) AND LLJ/ LIFT AHEAD OF THE OCCLUDED/WARM FRONTS MOVES IN. THE 12Z GFS ENSEMBLE MEAN ALSO KEEPS THE RIDGE IN PLACE WITH SLOWER PCPN ONSET THAN THE OPERATIONAL GFS. HOWEVER...THERE IS STILL SOME UNCERTAINTY WITH POTENTIAL FOR SHRTWV MOVING OUT OF THE PLAINS IN WAA ISENTROPIC LIFT REGIME TO ADD SHRA/TSRA PCPN CHANCES FOR ALL BUT ERN PORTION OF THE CWA BY AFTERNOON. SUN...THE SLOWER/STRONGER MORE CONSISTENT UKMET WAS PREFERRED WITH THE NRN PLAINS LOW. THIS WOULD KEEP BETTER SHRA/TSRA CHANCES GOING THROUGH SUN COMPARED TO THE GFS WHICH PUSHES THE FRONT THROUGH MORE QUICKLY AS ITS MID LVL AND SFC LOW MOVES INTO NRN ONTARIO. MON-THU...MDLS CONTINUE TO SHOW DIFFERENCES IN PROGRESSION OF 500 MB LOW MON INTO TUE AND STRENGTH OF THE RDG INTO THE LAKES BY WED-THU. THE 00Z/06Z/02 GFS REMAIN MORE PROGRESSIVE WITH THE H5 AND SFC LOW COMPARED TO THE 00Z/02 UKMET/CANADIAN/ECMWF. WHILE KEEPING THE MID LVL TROF AND SFC LOW CLOSER TO THE WRN LAKES WOULD SUPPORT BETTER PCPN CHANCES...EITHER SCENARIO WOULD LEAVE ENOUGH UNSTABLE AIR OVER THE REGION SO THAT ANY TRAILING SHRTWVS OR WEAK SFC BOUNDARIES COULD SET OFF SOME SHRA/TSRA. TUE-THU...THE GFS...SUPPORTED BY THE CANADIAN MDL AND GFS ENS MEAN...SUGGESTS MID LEVEL AND SFC RIDGING WILL BRING KEEP MAINLY DRY WEATHER OVER THE REGION WITH MAIN SFC BOUNDARY WELL TO THE SOUTH AND WEST. 06Z/02 DEWPOINTS AND ASSOCIATED CAPE/LI FROM TUE INTO WED SEEMED A BIT OVERDONE...SO NO DIURNAL SHRA/TSRA WERE ADDED AT THIS POINT. MID LEVEL WARMING/DRYING UNDER THE RDG SHOULD ALSO LIMIT CONVECTION POTENTIAL. && .MQT...WATCHES/WARNINGS/ADVISORIES...NONE. && $$ JLB mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAND RAPIDS MI 338 PM EDT THU JUN 2 2005 .SHORT TERM... THE MAIN WEATHER CHALLENGE DEALS THE THUNDERSTORM POTENTIAL AND ASSOCIATED HAZARDS THIS WEEKEND. INGREDIENTS APPEAR TO BE COMING TOGETHER FOR A MORE WIDESPREAD AREA OF SHOWERS AND THUNDERSTORMS TO FORM AND CROSS THE REGION...EITHER LATER SATURDAY OR SATURDAY NIGHT. FIRST OFF...THE GULF IS OPEN AND DEEP MOISTURE IS ALREADY STREAMING UP THE MISSISSIPPI VALLEY. PRECIPITABLE WATER VALUES OF OVER 1.5 INCHES ARE LIFTING NORTHWARD THROUGH THE CONFLUENCE OF THE MS AND OH RIVERS REGION. SECOND THIS MOISTURE...EVENTUALLY LEADS TO INSTABILITY...WHICH MAY BE ENHANCED BY HEATING ON SATURDAY. FINALLY A RATHER STRONG LIFTING MECHANISM IN THE FORM OF AN UPPER LOW IS LIFTING OUT OF NORTHERN MEXICO AND IS HEADED TOWARD THE CENTRAL PLAINS. ULTIMATELY IT TRACKS THROUGH OR NEAR SOUTHWEST LOWER MICHIGAN LATER SATURDAY OR SATURDAY NIGHT. AS IS TYPICAL OF THESE TYPES OF SYSTEMS...THEY GENERATE A LOW LEVEL JET WITH THE MAIN CONVECTION FORMING ON THE NOSE OF THE JET. THE GFS IS CLEARLY SLOWER WITH THIS PROCESS AND SUGGESTS A SATURDAY NIGHT OR LATER EVENT. THE NAM IS MUCH QUICKER...BRINGING PLENTY OF INSTABILITY IN FOR SATURDAY. OF PARTICULAR NOTE IS THE RUC13...WHICH SEEMS TO HAVE A GOOD HANDLE ON THE SURFACE DEWPOINTS BRINING VALUES UP INTO THE LOW 60S SATURDAY MORNING. THIS MODEL INDICATES A RATHER ACTIVE WARM FRONT LIFTING INTO SOUTHWEST LOWER MICHIGAN ON SATURDAY...WHICH COULD BE OUR BUSIEST DAY OF THE WEEKEND. CAPE VALUES GREATER THAN 3K J/KG BUILD INTO NORTH CENTRAL IL COMBINED WITH HIGH HELICITY. I WILL KEEP THE CHANCE FOR THUNDERSTORMS GOING THROUGH SATURDAY AND SATURDAY NIGHT. I HAVE INCREASED THE PROBABILITIES SATURDAY NIGHT. SINCE THE MAIN SYSTEM WILL BE ENTERING A DENSER AREA OF RAOBS OVERNIGHT...WE CAN BETTER ASSESS THE TIMING OF THIS SYSTEM AS IT NEARS. I WILL UPDATE THE HAZARDOUS WEATHER OUTLOOK TO HIGHLIGHT SOME OF THE POTENTIAL HAZARDS. OTHERWISE THE CURRENT FORECAST IS LOOKING GOOD WITH NO MAJOR CHANGES PLANNED. THE WEAK UPPER LOW IN IL AT THIS TIME IS LIFTING SLOWLY BUT STEADILY NORTHEAST. LIGHT RAIN/SPRINKLES WILL MOVE INTO MY SOUTHERN COUNTIES THIS EVENING. .LONG TERM... WE'LL GET INTO A FAIRLY ACTIVE WX PATTERN IN THE EXTENDED PERIOD WITH A CHANCE OF CONVECTION SUNDAY INTO MONDAY AND PERHAPS TUESDAY... AND THEN AGAIN TOWARDS LATE NEXT WEEK. WE'LL HAVE A CHC FOR TSTORMS SUNDAY SINCE PRETTY DECENT LOW LEVEL MOISTURE WILL BE IN PLACE AS WELL AS INCREASING INSTABILITY LATE SUNDAY MORNING AND AFTERNOON. 12Z ETA GUIDANCE LOOKS DRY FOR OUR AREA SUNDAY, BUT I DON'T BELIEVE IT, SINCE IT IS UNDERDONE IN TERMS OF 925-850 MB RH. WE'LL GO ALONG WITH 12Z GFS GUIDANCE AS WELL AS OUR PREVIOUS EXTENDED RANGE FORECAST TO LEAVE MENTION OF A CHC OF STORMS IN MONDAY'S FORECAST TOO. WE CONSIDERED GOING WITH A DRY FCST TUESDAY SINCE IT NOW APPEARS A SFC RIDGE WILL TAKE HOLD OF OUR WX. GFS GUIDANCE HAS TRENDED MORE TOWARD THE CANADIAN IN SHOWING DRY WX TUE INTO WED. HOWEVER AT THIS POINT WE'LL HOLD ONTO MENTION OF A FEW STORMS INTO TUE PER COORD WITH DTX/IWX. THE MID SHIFT WILL NEED TO REEVALUATE THIS AND MODEL TRENDS WITH REGARD TO PCPN CHANCES TUE/WED. THE WX PATTERN WILL BECOME MORE ACTIVE ONCE AGAIN LATE NEXT WEEK AS A SHARP H5 TROF MOVES EAST INTO THE PLAINS STATES AND A VIGOROUS COLD FRONT FOCUSES CONVECTION ACROSS THAT AREA. THIS ALL WILL LIKELY SHIFT EAST INTO OUR REGION LATE NEXT WEEK. && .GRR WATCHES/WARNINGS/ADVISORIES...NONE. && $$ MJS LAURENS mi AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE RALEIGH NC 930 PM EDT THU JUN 2 2005 .SHORT TERM (REST OF TONIGHT)... CONVECTION TO OUR SOUTH ALONG THE FRONT IS DISSIPATING ONCE IT MOVES NORTH INTO THE STABLE COLD DOME. ISENTROPIC LIFT AND LOW LEVEL CONVERGENCE APPEAR VERY WEAK IN THE MODELS OVERNIGHT. HOWEVER WITH THE APPROACHING MID LEVEL CLOSED LOW AND AN UPPER LEVEL JET STREAK ACTING ON A VERY MOIST AIR MASS...ADDITIONAL PRECIP MAY DEVELOP OVERNIGHT. THUS WILL KEEP LIKELY TO CATEGORICAL POPS AS THEY ARE. IT IS NOT LIKELY THAT THE PRECIP WILL BE HEAVY AT ANY TIME TONIGHT...BUT AS IT CANNOT BE RULED OUT WILL LEAVE THE FLASH FLOOD WATCH ALONE. TEMPERATURES ARE RUNNING CLOSE TO FORECAST VALUES AND WILL NOT BE CHANGED. && .PREVIOUS DISCUSSION... (ISSUED 635 PM EDT THU JUN 2 2005) SHORT TERM (REST OF TONIGHT)... AN EARLY UPDATE WILL BE SENT TO ADJUST POPS AND ADD ISOLATED THUNDERSTORMS SOUTHEAST. AREA OF CONVECTIVE PRECIP OVER NE SC IS SPREADING NORTH AND WILL MOVE INTO THE EASTERN SANDHILLS/SOUTHERN COASTAL PLAIN COUNTIES THIS EVENING. POPS THERE WILL BE RAISED TO CATEGORICAL. A FEW THUNDERSTORMS MAY ALSO PUSH INTO THE AREA...ESPECIALLY IN SAMPSON COUNTY NEAR THE FRONT. LIKELY POPS WILL BE CONTINUED ELSEWHERE OVERNIGHT. TEMPERATURES APPEAR ON TRACK BUT WILL REASSESS LATER THIS EVENING. KRAX...WHICH HAD BEEN USING THE STRATIFORM Z-R RELATIONSHIP...WILL BE CHANGED TO THE STANDARD Z-R RELATIONSHIP DUE TO THE APPROACHING CONVECTION. PREVIOUS DISCUSSION... (ISSUED 305 PM EDT THU JUN 2 2005) SHORT TERM (TONIGHT)... THE WARM FRONT HAS MOVED EXTREMELY SLOWLY NORTHWARD TODAY AND HAS REACHED THE SOUTHEAST TIP OF NC. NORTHWEST PIEDMONT REMAINS QUITE STABLE AND RUC SOUNDINGS INDICATE THAT THE FRONT SHOULD NOT BE ABLE TO MOVE ANY FARTHER NW THAN THE COASTAL PLAIN TONIGHT. DEEP MOIST FLOW AND MODERATE ISENTROPIC UPGLIDE PERSISTS THROUGH TONIGHT. WILL CONTINUE LIGHTLY POPS... WITH THE HIGHEST IN THE WEST WHERE THE POSITIVE VORTICITY ADVECTION AND WEAK LEFT FRONT JET QUAD DYNAMICS WILL BE OPTIMAL... EVEN DISCOUNTING THE APPARENT CONVECTIVE FEEDBACK ON THE GFS. THE WRF BRINGS THE CONVECTION CURRENTLY OVER THE DEEP SOUTH NORTHEASTWARD INTO NC TONIGHT... ALBEIT IN A WEAKENED STATE. THE FAR SOUTHWEST COUNTIES OF THE CWA RECEIVED 1 TO 3 INCHES OF RAIN SINCE LAST NIGHT AND THE COUNTIES REPORTED CONSIDERABLE PONDING OF WATER ON ROADS EARLIER TODAY WHICH CAUSED NUMEROUS ACCIDENTS. WHILE THE RAIN TONIGHT IS NOT EXPECTED TO BE TERRIBLY HEAVY... ENOUGH STEADY MODERATE RAIN IS ANTICIPATED TO POSE A THREAT OF HIGH WATER ON ROADS & RISING CREEKS. WILL ISSUE A BORDERLINE FLOOD WATCH FOR AREAS FROM LEXINGTON AND ASHEBORO SOUTHWEST TO TROY... ALBEMARLE... AND WADESBORO. TEMPERATURES NOT LIKELY TO DROP MORE THAN A DEGREE OR TWO IF THAT FROM CURRENT DEWPOINTS. LONG TERM (FRIDAY THROUGH THURSDAY)... FRIDAY THROUGH SATURDAY: THE MID LEVEL TROUGH DRIFTS FROM TX ACROSS NW NC AND VA THROUGH THE PERIOD. WE LOSE THE LARGE SCALE DYNAMICS FRIDAY BUT AT LEAST SOUTHEAST SECTIONS OF THE CWA SHOULD BREAK OUT ENOUGH FOR SCATTERED CONVECTION BY THE AFTERNOON AND INTO THE EVENING. FORECAST CAPES GET ABOVE 1000 J/KG & THE WIND PROFILE DOES VEER A BIT BUT THE DEEP LAYER SHEAR IS ONLY ABOUT 25 KT AND THE FREEZING LEVEL IS FAIRLY HIGH... BUT WILL HAVE TO KEEP A WATCH ON ANY DISCRETE CELLS TOMORROW. WILL RETAIN THE WEDGE REGIME (AND MORE STRATIFORM PRECIP) OVER THE WESTERN PIEDMONT FRI. WITH LOW CONFIDENCE IN TEMPERATURE DETAILS FRI... WILL MAKE ONLY MINOR CHANGES TO THE CURRENT HIGHS RANGING FROM THE UPPER 60S NW TO THE UPPER 70S TO NEAR 80 SOUTHEAST. BY SATURDAY THE LIGHT WESTERLY FLOW BEHIND THE TROUGH SHOULD SCOUR OUT ANY REMAINS OF THE HYBRID WEDGE AIR MASS. WILL HAVE JUST ISOLATED AFTERNOON STORMS SAT. CURRENT HIGHS LOOK GOOD. SUNDAY THROUGH THURSDAY: MEDIUM RANGE GUIDANCE MODELS AGREE ON STACKED RIDGING DOMINATING THE SOUTHEAST STATES SUN THROUGH MON WITH WEAK LEE TROUGHING OVER THE RAH CWA. WILL CONTINUE WITH ABOVE NORMAL TEMPS SUN/MON AND RAIN PROBABILITIES BELOW CLIMATOLOGICAL NORMALS. WEAK 850 MB RETURN FLOW TRIES TO BRING MOISTURE UP FROM THE GULF FOR TUE AS A BAGGY UPPER TROUGH ARRIVES FROM THE WEST... AND WILL CARRY SHOWER AND STORM CHANCES TUE AFTERNOON INTO WED. THE LATEST GFS RUN TAKES THIS WEAK UPPER TROUGH OFFSHORE EARLY WED WITH 850 MB FLOW RETURNING TO NORTHWESTERLY... THEN WEAK RIDGING FOLLOWS LATE WED INTO THU WITH UPPER VORTICES OVER SW AND ERN CANADA. HOWEVER THE WIND FLOW THROUGH THE COLUMN BECOMES SO WEAK AND NONDESCRIPT THAT IT WILL BE TOUGH TO PINPOINT ANY BOUNDARIES OR NOTABLE FORCING MECHANISMS. WILL GO WITH UNMENTIONED SLIGHT CHANCE RAIN CHANCES WED NIGHT INTO THU. TEMPS NEAR OR SLIGHTLY ABOVE NORMAL TUE-THU. AVIATION... MIX OF LIFR AND IFR CEILINGS ACROSS THE AREA AT THIS TIME. EXPECT WIDESPREAD LIFR CEILINGS AS MIDNIGHT APPROACHES. AFTER MIDNIGHT VISIBILITIES AT OR BELOW ONE MILE NORTH OF THE WARM FRONT IN FOG WITH MINIMALLY BETTER VISIBILITIES TO THE SOUTH. FRONT APPEARS TO BE MAKING MINIMAL PROGRESS NORTH AND IS FORECAST TO BE IN THE VICINITY OF FAYETTEVILLE NEAR SUNSET AND NEAR RALEIGH AND ROCKY MOUNT TOWARD SUNRISE. MINIMAL NORTHWARD PROGRESS OF THE FRONT IN THE WEST. CEILINGS AND VISIBILITIES IMPROVE A FEW HOURS AFTER SUNRISE FRIDAY IMPROVING TO IFR. && .RAH WATCHES/WARNINGS/ADVISORIES... FLOOD WATCH FOR NCZ038-039-073-074-083 UNTIL 4 AM FRIDAY. && $$ SHORT TERM...DGS nc AREA FORECAST DISCUSSION...UPDATE NATIONAL WEATHER SERVICE RALEIGH NC 635 PM EDT THU JUN 2 2005 .SHORT TERM (REST OF TONIGHT)... AN EARLY UPDATE WILL BE SENT TO ADJUST POPS AND ADD ISOLATED THUNDERSTORMS SOUTHEAST. AREA OF CONVECTIVE PRECIP OVER NE SC IS SPREADING NORTH AND WILL MOVE INTO THE EASTERN SANDHILLS/SOUTHERN COASTAL PLAIN COUNTIES THIS EVENING. POPS THERE WILL BE RAISED TO CATEGORICAL. A FEW THUNDERSTORMS MAY ALSO PUSH INTO THE AREA...ESPECIALLY IN SAMPSON COUNTY NEAR THE FRONT. LIKELY POPS WILL BE CONTINUED ELSEWHERE OVERNIGHT. TEMPERATURES APPEAR ON TRACK BUT WILL REASSESS LATER THIS EVENING. KRAX...WHICH HAD BEEN USING THE STRATIFORM Z-R RELATIONSHIP...WILL BE CHANGED TO THE STANDARD Z-R RELATIONSHIP DUE TO THE APPROACHING CONVECTION. && .PREVIOUS DISCUSSION... (ISSUED 305 PM EDT THU JUN 2 2005) SHORT TERM (TONIGHT)... THE WARM FRONT HAS MOVED EXTREMELY SLOWLY NORTHWARD TODAY AND HAS REACHED THE SOUTHEAST TIP OF NC. NORTHWEST PIEDMONT REMAINS QUITE STABLE AND RUC SOUNDINGS INDICATE THAT THE FRONT SHOULD NOT BE ABLE TO MOVE ANY FARTHER NW THAN THE COASTAL PLAIN TONIGHT. DEEP MOIST FLOW AND MODERATE ISENTROPIC UPGLIDE PERSISTS THROUGH TONIGHT. WILL CONTINUE LIGHTLY POPS... WITH THE HIGHEST IN THE WEST WHERE THE POSITIVE VORTICITY ADVECTION AND WEAK LEFT FRONT JET QUAD DYNAMICS WILL BE OPTIMAL... EVEN DISCOUNTING THE APPARENT CONVECTIVE FEEDBACK ON THE GFS. THE WRF BRINGS THE CONVECTION CURRENTLY OVER THE DEEP SOUTH NORTHEASTWARD INTO NC TONIGHT... ALBEIT IN A WEAKENED STATE. THE FAR SOUTHWEST COUNTIES OF THE CWA RECEIVED 1 TO 3 INCHES OF RAIN SINCE LAST NIGHT AND THE COUNTIES REPORTED CONSIDERABLE PONDING OF WATER ON ROADS EARLIER TODAY WHICH CAUSED NUMEROUS ACCIDENTS. WHILE THE RAIN TONIGHT IS NOT EXPECTED TO BE TERRIBLY HEAVY... ENOUGH STEADY MODERATE RAIN IS ANTICIPATED TO POSE A THREAT OF HIGH WATER ON ROADS & RISING CREEKS. WILL ISSUE A BORDERLINE FLOOD WATCH FOR AREAS FROM LEXINGTON AND ASHEBORO SOUTHWEST TO TROY... ALBEMARLE... AND WADESBORO. TEMPERATURES NOT LIKELY TO DROP MORE THAN A DEGREE OR TWO IF THAT FROM CURRENT DEWPOINTS. LONG TERM (FRIDAY THROUGH THURSDAY)... FRIDAY THROUGH SATURDAY: THE MID LEVEL TROUGH DRIFTS FROM TX ACROSS NW NC AND VA THROUGH THE PERIOD. WE LOSE THE LARGE SCALE DYNAMICS FRIDAY BUT AT LEAST SOUTHEAST SECTIONS OF THE CWA SHOULD BREAK OUT ENOUGH FOR SCATTERED CONVECTION BY THE AFTERNOON AND INTO THE EVENING. FORECAST CAPES GET ABOVE 1000 J/KG & THE WIND PROFILE DOES VEER A BIT BUT THE DEEP LAYER SHEAR IS ONLY ABOUT 25 KT AND THE FREEZING LEVEL IS FAIRLY HIGH... BUT WILL HAVE TO KEEP A WATCH ON ANY DISCRETE CELLS TOMORROW. WILL RETAIN THE WEDGE REGIME (AND MORE STRATIFORM PRECIP) OVER THE WESTERN PIEDMONT FRI. WITH LOW CONFIDENCE IN TEMPERATURE DETAILS FRI... WILL MAKE ONLY MINOR CHANGES TO THE CURRENT HIGHS RANGING FROM THE UPPER 60S NW TO THE UPPER 70S TO NEAR 80 SOUTHEAST. BY SATURDAY THE LIGHT WESTERLY FLOW BEHIND THE TROUGH SHOULD SCOUR OUT ANY REMAINS OF THE HYBRID WEDGE AIR MASS. WILL HAVE JUST ISOLATED AFTERNOON STORMS SAT. CURRENT HIGHS LOOK GOOD. SUNDAY THROUGH THURSDAY: MEDIUM RANGE GUIDANCE MODELS AGREE ON STACKED RIDGING DOMINATING THE SOUTHEAST STATES SUN THROUGH MON WITH WEAK LEE TROUGHING OVER THE RAH CWA. WILL CONTINUE WITH ABOVE NORMAL TEMPS SUN/MON AND RAIN PROBABILITIES BELOW CLIMATOLOGICAL NORMALS. WEAK 850 MB RETURN FLOW TRIES TO BRING MOISTURE UP FROM THE GULF FOR TUE AS A BAGGY UPPER TROUGH ARRIVES FROM THE WEST... AND WILL CARRY SHOWER AND STORM CHANCES TUE AFTERNOON INTO WED. THE LATEST GFS RUN TAKES THIS WEAK UPPER TROUGH OFFSHORE EARLY WED WITH 850 MB FLOW RETURNING TO NORTHWESTERLY... THEN WEAK RIDGING FOLLOWS LATE WED INTO THU WITH UPPER VORTICES OVER SW AND ERN CANADA. HOWEVER THE WIND FLOW THROUGH THE COLUMN BECOMES SO WEAK AND NONDESCRIPT THAT IT WILL BE TOUGH TO PINPOINT ANY BOUNDARIES OR NOTABLE FORCING MECHANISMS. WILL GO WITH UNMENTIONED SLIGHT CHANCE RAIN CHANCES WED NIGHT INTO THU. TEMPS NEAR OR SLIGHTLY ABOVE NORMAL TUE-THU. AVIATION... MIX OF LIFR AND IFR CEILINGS ACROSS THE AREA AT THIS TIME. EXPECT WIDESPREAD LIFR CEILINGS AS MIDNIGHT APPROACHES. AFTER MIDNIGHT VISIBILITIES AT OR BELOW ONE MILE NORTH OF THE WARM FRONT IN FOG WITH MINIMALLY BETTER VISIBILITIES TO THE SOUTH. FRONT APPEARS TO BE MAKING MINIMAL PROGRESS NORTH AND IS FORECAST TO BE IN THE VICINITY OF FAYETTEVILLE NEAR SUNSET AND NEAR RALEIGH AND ROCKY MOUNT TOWARD SUNRISE. MINIMAL NORTHWARD PROGRESS OF THE FRONT IN THE WEST. CEILINGS AND VISIBILITIES IMPROVE A FEW HOURS AFTER SUNRISE FRIDAY IMPROVING TO IFR. && .RAH WATCHES/WARNINGS/ADVISORIES... FLOOD WATCH FOR NCZ038-039-073-074-083 UNTIL 4 AM FRIDAY. && $$ SHORT TERM...DGS nc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE RALEIGH NC 305 PM EDT THU JUN 2 2005 .SHORT TERM (TONIGHT)... THE WARM FRONT HAS MOVED EXTREMELY SLOWLY NORTHWARD TODAY AND HAS REACHED THE SOUTHEAST TIP OF NC. NORTHWEST PIEDMONT REMAINS QUITE STABLE AND RUC SOUNDINGS INDICATE THAT THE FRONT SHOULD NOT BE ABLE TO MOVE ANY FARTHER NW THAN THE COASTAL PLAIN TONIGHT. DEEP MOIST FLOW AND MODERATE ISENTROPIC UPGLIDE PERSISTS THROUGH TONIGHT. WILL CONTINUE LIGHTLY POPS... WITH THE HIGHEST IN THE WEST WHERE THE POSITIVE VORTICITY ADVECTION AND WEAK LEFT FRONT JET QUAD DYNAMICS WILL BE OPTIMAL... EVEN DISCOUNTING THE APPARENT CONVECTIVE FEEDBACK ON THE GFS. THE WRF BRINGS THE CONVECTION CURRENTLY OVER THE DEEP SOUTH NORTHEASTWARD INTO NC TONIGHT... ALBEIT IN A WEAKENED STATE. THE FAR SOUTHWEST COUNTIES OF THE CWA RECEIVED 1 TO 3 INCHES OF RAIN SINCE LAST NIGHT AND THE COUNTIES REPORTED CONSIDERABLE PONDING OF WATER ON ROADS EARLIER TODAY WHICH CAUSED NUMEROUS ACCIDENTS. WHILE THE RAIN TONIGHT IS NOT EXPECTED TO BE TERRIBLY HEAVY... ENOUGH STEADY MODERATE RAIN IS ANTICIPATED TO POSE A THREAT OF HIGH WATER ON ROADS & RISING CREEKS. WILL ISSUE A BORDERLINE FLOOD WATCH FOR AREAS FROM LEXINGTON AND ASHEBORO SOUTHWEST TO TROY... ALBEMARLE... AND WADESBORO. TEMPERATURES NOT LIKELY TO DROP MORE THAN A DEGREE OR TWO IF THAT FROM CURRENT DEWPOINTS. && .LONG TERM (FRIDAY THROUGH THURSDAY)... FRIDAY THROUGH SATURDAY: THE MID LEVEL TROUGH DRIFTS FROM TX ACROSS NW NC AND VA THROUGH THE PERIOD. WE LOSE THE LARGE SCALE DYNAMICS FRIDAY BUT AT LEAST SOUTHEAST SECTIONS OF THE CWA SHOULD BREAK OUT ENOUGH FOR SCATTERED CONVECTION BY THE AFTERNOON AND INTO THE EVENING. FORECAST CAPES GET ABOVE 1000 J/KG & THE WIND PROFILE DOES VEER A BIT BUT THE DEEP LAYER SHEAR IS ONLY ABOUT 25 KT AND THE FREEZING LEVEL IS FAIRLY HIGH... BUT WILL HAVE TO KEEP A WATCH ON ANY DISCRETE CELLS TOMORROW. WILL RETAIN THE WEDGE REGIME (AND MORE STRATIFORM PRECIP) OVER THE WESTERN PIEDMONT FRI. WITH LOW CONFIDENCE IN TEMPERATURE DETAILS FRI... WILL MAKE ONLY MINOR CHANGES TO THE CURRENT HIGHS RANGING FROM THE UPPER 60S NW TO THE UPPER 70S TO NEAR 80 SOUTHEAST. BY SATURDAY THE LIGHT WESTERLY FLOW BEHIND THE TROUGH SHOULD SCOUR OUT ANY REMAINS OF THE HYBRID WEDGE AIR MASS. WILL HAVE JUST ISOLATED AFTERNOON STORMS SAT. CURRENT HIGHS LOOK GOOD. SUNDAY THROUGH THURSDAY: MEDIUM RANGE GUIDANCE MODELS AGREE ON STACKED RIDGING DOMINATING THE SOUTHEAST STATES SUN THROUGH MON WITH WEAK LEE TROUGHING OVER THE RAH CWA. WILL CONTINUE WITH ABOVE NORMAL TEMPS SUN/MON AND RAIN PROBABILITIES BELOW CLIMATOLOGICAL NORMALS. WEAK 850 MB RETURN FLOW TRIES TO BRING MOISTURE UP FROM THE GULF FOR TUE AS A BAGGY UPPER TROUGH ARRIVES FROM THE WEST... AND WILL CARRY SHOWER AND STORM CHANCES TUE AFTERNOON INTO WED. THE LATEST GFS RUN TAKES THIS WEAK UPPER TROUGH OFFSHORE EARLY WED WITH 850 MB FLOW RETURNING TO NORTHWESTERLY... THEN WEAK RIDGING FOLLOWS LATE WED INTO THU WITH UPPER VORTICES OVER SW AND ERN CANADA. HOWEVER THE WIND FLOW THROUGH THE COLUMN BECOMES SO WEAK AND NONDESCRIPT THAT IT WILL BE TOUGH TO PINPOINT ANY BOUNDARIES OR NOTABLE FORCING MECHANISMS. WILL GO WITH UNMENTIONED SLIGHT CHANCE RAIN CHANCES WED NIGHT INTO THU. TEMPS NEAR OR SLIGHTLY ABOVE NORMAL TUE-THU. && .AVIATION... MIX OF LIFR AND IFR CEILINGS ACROSS THE AREA AT THIS TIME. EXPECT WIDESPREAD LIFR CEILINGS AS MIDNIGHT APPROACHES. AFTER MIDNIGHT VISIBILITIES AT OR BELOW ONE MILE NORTH OF THE WARM FRONT IN FOG WITH MINIMALLY BETTER VISIBILITIES TO THE SOUTH. FRONT APPEARS TO BE MAKING MINIMAL PROGRESS NORTH AND IS FORECAST TO BE IN THE VICINITY OF FAYETTEVILLE NEAR SUNSET AND NEAR RALEIGH AND ROCKY MOUNT TOWARD SUNRISE. MINIMAL NORTHWARD PROGRESS OF THE FRONT IN THE WEST. CEILINGS AND VISIBILITIES IMPROVE A FEW HOURS AFTER SUNRISE FRIDAY IMPROVING TO IFR. && .RAH WATCHES/WARNINGS/ADVISORIES... FLOOD WATCH FOR NCZ038-039-073-074-083 FROM 6 PM TONIGHT TO 4 AM FRIDAY. && $$ SHORT TERM...RLH/HARTFIELD LONG TERM...HARTFIELD AVIATION...RLH nc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON OH 350 PM EDT THU JUN 02 2005 .SHORT TERM (TONIGHT THROUGH FRIDAY NIGHT)... AREA IS ON THE MOIST EAST SIDE OF STACKED LOW OVER THE MID MISSISSIPPI VALLEY. LOW IS PROGGED TO TRAVEL SLOWLY EAST UP THE OHIO VALLEY DURING THE SHORT TERM, WITH ILN AREA EXPERIENCING MOISTURE ADVECTION THROUGH FRIDAY. KEPT CHANCE POPS TONIGHT. WITH NAM AND GFS SHOWING BETTER MID LEVEL SUPPORT, RAISED POPS ON FRIDAY, LIKELY IN SOUTH, HIGH CHANCE IN NORTH. KEPT CHANCE OF THUNDER FOR AFTERNOON. DRY CONDITIONS WILL RETURN FRIDAY NIGHT WITH SYSTEM EXITING NORTHEAST. LOWERED TEMPS FRIDAY WITH RAIN EXPECTED. REST OF TEMPS RELATIVELY UNCHANGED. && .LONG TERM (SATURDAY THROUGH THURSDAY)... HAVE OPTED CLOSE TO THE GFS FOR EXTENDED PERIOD. WARM FRONT LIFTS NORTHEAST ACROSS REGION ON SATURDAY. SOME ISENTROPIC LIFT ASSOCIATED WITH THE FRONT DEVELOPS SO HAVE CHANCE POPS DURING THIS TIME. REGION REMAINS IN WARM SECTOR AND SOME INSTABILITY EXISTS BEFORE COLD FRONT PUSHES SOUTH BY LATE TUESDAY/EARLY WEDNESDAY. HIGH PRESSURE BUILDS IN FROM THE GREAT LAKES FOR END OF EXTENDED PERIOD. HAVE NOT STRAYED TO FAR FROM MAV NUMBERS FOR TEMPS. && .AVIATION (18Z-18Z)... ISENTROPIC LIFT PUSHES NORTH OF THE AREA AFTER 18Z...AND THE RUC SHOWS THIS TREND OF MUCH LESS PCPN COVERAGE THIS AFTERNOON. CIGS WERE MVFR AT KCVG AND KLUK...WITH VFR ELSEWHERE AT THIS TIME...BUT THE OTHER TAF SITES WILL PROGRESS INTO MVFR CIGS AS WELL OVER THE NEXT SEVERAL HOURS. AS UPPER LOW APPROACHES AFTER 06Z...CHANCE OF PCPN WILL INCREASE SOUTH TO NORTH 06Z-12Z...WITH THE NAM PRODUCING MORE QPF THAN THE GFS AFTER 12Z. THIS IS REFLECTED IN MUCH HIGHER MET THAN MAV POPS. WILL CARRY VCSH AND PERHAPS TEMPOS AT THIS TIME. INSTABILITY REMAINS MEAGER...SO THUNDER WILL NOT BE MENTIONED. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ oh AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON OH 1140 AM EDT THU JUN 2 2005 .SHORT TERM (TODAY)... A WIDE BAND OF SHOWERS WAS MOVING NORTH ACROSS THE AREA THIS MORNING. THE PCPN WAS EXHIBITING MUCH LESS COVERAGE JUST SOUTH OF THE OHIO RIVER. AS THE AFTERNOON PROGRESSES...THE BEST LIFT WILL MOVE INTO NORTHERN OHIO AND INDIANA. WITH THE LACK OF INSTABILITY BEHIND THIS...SHOWER COVERAGE WILL FALL OFF QUICKLY. CURRENT FCST POINTS TO THIS...SO WILL MAINLY TWEAK SOME AFTERNOON WORDING. && .AVIATION (18Z-18Z)... ISENTROPIC LIFT PUSHES NORTH OF THE AREA AFTER 18Z...AND THE RUC SHOWS THIS TREND OF MUCH LESS PCPN COVERAGE THIS AFTERNOON. CIGS WERE MVFR AT KCVG AND KLUK...WITH VFR ELSEWHERE AT THIS TIME...BUT THE OTHER TAF SITES WILL PROGRESS INTO MVFR CIGS AS WELL OVER THE NEXT SEVERAL HOURS. AS UPPER LOW APPROACHES AFTER 06Z...CHANCE OF PCPN WILL INCREASE SOUTH TO NORTH 06Z-12Z...WITH THE NAM PRODUCING MORE QPF THAN THE GFS AFTER 12Z. THIS IS REFLECTED IN MUCH HIGHER MET THAN MAV POPS. WILL CARRY VCSH AND PERHAPS TEMPOS AT THIS TIME. INSTABILITY REMAINS MEAGER...SO THUNDER WILL NOT BE MENTIONED. && .PREVIOUS DISCUSSION... (ISSUED 400 AM EDT THU JUN 2 2005) SHORT TERM (TODAY THROUGH SATURDAY NIGHT)... DIFFICULT FORECAST OVER THE NEXT FEW DAYS WITH CHANCE POPS IN THROUGH THE PERIOD FOR MOST OF CWA. EARLY SHOT OF RAIN TODAY LOOKS TO DIMINISH THIS AFTERNOON OR EARLY TONIGHT AS THE INITIAL UPPER SUPPORT OF THE LOBE OF VORTICITY MOVES N OF FCST AREA. AM LOWERING POPS OVERNIGHT OVER MUCH OF FCST AREA AS NAM AND NGM...GFS TO A LESSER EXTENT...QUICKLY TURN OFF ANY PRECIP ACCUMS FROM 18-0Z. UPPER LOW TRACKS THROUGH FCST AREA EARLY FRI WITH A LAGGING SFC LOW. SFC LOW WEAKENS TO MORE OF AN AREA OF TROFFINESS AS IT TRACKS OVER FCST AREA DURING THE DAY FRI...BUT H5 CIRCULATION AT TIME OF MAX HEATING WILL HELP AIDE IN DEVELOPMENT OF SHOWERS AGAIN...AND POSSIBLY SOME THUNDER. GENERALLY TRENDED TOWARDS FWC TEMPERATURES OVER THE NEXT 36 HOURS. CURRENT READINGS ARE NOT THAT FAR FROM EXPECTED HIGHS TODAY AND WITH INCOMING PRECIP...A NEAR STEADY OR SLOW RISE SEEMS REASONABLE. LONG TERM (SUNDAY THROUGH WEDNESDAY)... NO CHANGES FROM PREVIOUS FCST. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ oh AREA FORECAST DISCUSSION...CORRECTED NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC 915 PM EDT THU JUN 2 2005 CORRECTED FOR TYPOS .SHORT TERM (REST OF TONIGHT)... NOT AN EASY FORECAST AS CONVECTION THUS FAR HAS MAINLY BEEN CONFINED TO AREAS OF SURFACE-BASED INSTABILITY. WHERE COLD AIR DAMMING REMAINS ENTRENCHED...WHICH INCLUDES MOST OF THE FORECAST AREA SAVE THE TN BORDER COUNTIES...THERE HAS ONLY BEEN PATCHY DRIZZLE AND SOME STRATIFORM RAIN BLOWN DOWNSHEAR OF TSTM COMPLEXES OVER CENTRAL GEORGIA. THINKING IS AS SHORT WAVE LIFTS ACROSS THE REGION...BRINING WITH IT INCREASING UPPER DIVERGENCE AND STEEPENING MID LEVEL LAPSE RATES...MORE ELEVATED CONVECTION WILL BEGIN TO DEVELOP... PARTICULARLY OVER THE ERN HALF OF THE CWFA. THE NAM/S BEST SHOT OF H5 PVA DOESN/T COME THROUGH UNTIL AROUND 0900 UTC WHILE THE RUC IS NOT LOOKING AS ORGANIZED ALOFT AS EARLIER. BOTH MODELS ALSO HAVE THE STRONGEST H5 JET LOCATED MORE ACROSS THE MIDLANDS AND LOW COUNTRY. HOWEVER...IT DOES LOOK LIKE ELEVATED INSTABILITY WL INCREASE QUITE A BIT LATER TNGT...AIDED BY MID LEVEL DRYING AND H5 COLD POOL. DON/T SEE MUCH IN THE WAY OF LLVL CONVERGENCE ON THE MODELS...NOR IS THERE MUCH MOISTURE TRANSPORT. NONE OF THIS LENDS ME A GREAT DEAL OF CONFIDENCE THAT ELEVATED CONVECTION WL BECOME AS WIDESPREAD AS EARLIER THOUGHT. HOWEVER...THERE ARE ENOUGH COMPELLING FACTORS TO LEAVE FORECAST LARGELY INTACT...AND WL LEAVE FLOOD WATCH AS IS. THOUGH I WL CUT BACK ON HEAVY RAIN WORDING IN THE WRN ZONES AND REORIENT POPS TO TRY AND LINE UP A LITTLE BETTER WITH THE NEIGHBORS. && .PREVIOUS DISCUSSION... (ISSUED 250 PM EDT THU JUN 2 2005) SHORT TERM (TONIGHT THROUGH SUNDAY)... VISIBLE SATELLITE IMAGERY NICELY DEPICTS THE WEDGE FRONT AS EXTENDING FROM NEAR CAE TO ATL AND THEN BACK INTO THE SMOKY MOUNTAINS. THE SHORT RANGE MODELS ALL INITIALIZED THE SRN AL CONVECTION QUITE WELL...AND ALL AGREE IN BRINGING THE RESPONSIBLE 500 MB MAIN VORT LOBE UP INTO THE SRN APPALACHIANS AND SENDING THE ASSOCIATED CONVECTIVE DEBRIS NORTHWARD ACROSS THE WESTERN CAROLINAS AND NE GA OVERNIGHT. THIS BECOMES QUITE PROBLEMATIC IN LIGHT OF THE HEAVY RAINFALL OVER THE PAST 36 HOURS. THE HARDEST HIT EASTERN PIEDMONT HAS MANY REPORTS OF 2 TO 4 INCHES OF RAIN FOR THE EVENT THUS FAR. THIS AREA SHOULD ALSO SEE THE BEST COMBINATION OF INSTABILITY AROUND A SLOWLY DECAYING WEDGE...HIGH PRECIPITABLE WATER VALUES...AND A STRONG 850 MB EQUIVALENT POTENTIAL TEMPERATURE AXIS TONIGHT THROUGH TOMORROW. GIVEN THE RECENT HISTORY OF ISOLATED FLOODING...AND THE POTENTIAL FOR ADDITIONAL FLOODING WITH THIS SETUP...WILL ISSUE A FLOOD WATCH FROM ELBERTON TO CHARLOTTE TO SALISBURY THROUGH TOMORROW. MID LEVEL DRYING SHOULD WORK IN FROM THE SW FRIDAY...WITH 850 MB FLOW BECOMING MORE WESTERLY BY FRI NIGHT AS THE TROUGH LIFTS NORTHEAST. WILL CONTINUE TO FAVOR THE COOLER MAV TEMPERATURES FOR ONE MORE DAY AS THE WEDGE SHOULD FINALLY BREAK FRI AFTN. PRECIPITATION CHANCES WILL THEN SHIFT BACK TO THE WESTERN SLOPES THROUGH THE WEEKEND AS A SOUTHEAST RIDGE BUILDS IN OVER THE LINGERING LOW LEVEL MOISTURE. LONG TERM (SUNDAY NIGHT THROUGH THURSDAY)... BACKDOOR COLD FRONT EXPECTED TO MAKE PROGRESS TO THE SOUTH SUNDAY NITE AND MONDAY AS THE UPPER TROF DIGS DOWN OVER THE APPALACHIANS...ERODING WHATEVER IS LEFT OF THE UPPER RIDGE OVER THE SOUTHEAST STATES. HEIGHTS ALOFT FALL UNTIL MAJOR UPPER LOW OVER SOUTHERN CANADA SHIFTS EAST ENOUGH TO ALLOW FOR ANOTHER PERIOD OF SHORTWAVE RIDGING OVER THE REGION. MEANWHILE...CWFA WILL BE SUSCEPTIBLE TO PIECES OF UPPER ENERGY ROTATING OVER THE REGION IN A RATHER MOIST AND UNSTABLE ATMOSPHERE...WITH TEMERATURES PROGD INTO THE UPPER 80S FOR ALL EASTERN ZONES MONDAY...BEFORE COOLING FROM THE NORTH THROUGH MIDWEEK...AND A PERSISTENT CHANCE OF MAINLY AFTERNOON AND EVENING CONVECTION....ESPECIALLY IN THE SOUTHERN ZONES...CLOSER TO EVENTUALLY STALLING POSITION OF THE OLD BACKDOOR FRONT. AVIATION... ANOTHER DIRE TAF PACKAGE WITH PERSISTENT COLD AIR DAMMING...ALTHOUGH WE MAY BEGIN TO SEE EROSION OF THIS FEATURE FROM THE SOUTHWEST AND SOUTHEAST TONITE AND DURING THE OUTLOOK PERIOD. WE FEATURED PERSISTENT NORTHEAST SURFACE WINDS...AND CEILINGS RANGING FROM MVFR... TO IFR DURING CONVECTIVE CELLS. PRECIPITATION SHOULD BECOME WIDESPREAD AT ALL TAF LOCATIONS THIS EVENING AND FOR MOST OF THE OVERNIGHT WITH APPROACH OF A MAJOR SHORTWAVE AND WITH CWFA ENTERING FAVORABLE POSITION RELATIVE TO UPPER JET. VISIBILITIES MAY FALL TO IFR RANGE AT ANY TIME DURING HEAVY RAIN AT ALL THE TAF SITES THROUGH DAYBREAK FRIDAY. OUTLOOK PERIOD FEATURES IMPROVING CONDITIONS...ALTHOUGH THERE WILL BE NUMEROUS SHOWERS REMAINING THROUGH THE CONCLUSION OF THE OUTLOOK PERIOD...WITH VCSH ADVERTISED MOST LOCATIONS AND TEMPO GROUPS INCLUDED TO ACCOUNT FOR ANY RESIDUAL RAIN SHOWERS. PRECIPITATION CHARACTER SHOULD BE SHOWERY...BUT TSRA ADVERTISED AT TIMES OVERNIGHT AT KAND/KCLT...THE TWO TAF SITES MOST SUSCEPTIBLE TO EXPERIENCING PARTIAL OR PERMANENT EROSION OF OUR COLD AIR DAMMING REGIME. && .GSP WATCHES/WARNINGS/ADVISORIES... GA...FLOOD WATCH FOR GAZ029 UNTIL 6 PM FRIDAY. NC...FLOOD WATCH FOR NCZ057-071-072-082 UNTIL 6 PM FRIDAY. SC...FLOOD WATCH FOR SCZ009-011>014-019 UNTIL 6 PM FRIDAY. && $$ SHORT TERM...MCAVOY sc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC 915 PM EDT THU JUN 2 2005 .SHORT TERM (REST OF TONIGHT)... NOT AN EASY FORECAST AS CONVECTION THUS FAR HAS MAINLY BEEN CONFINED TO AREAS OF SURFACE-BASED INSTABILITY. WHERE COLD AIR DAMING REMAINS ENTRENCHED...WHICH INCLUDES MOST OF THE FORECAST AREA SAVE THE TN BORDER COUNTIES...THERE HAS ONLY BEEN PATCHY DRIZZLE AND SOME STRATIFORM RAIN BLOWN DOWNSHEAR OF TSTM COMPLEXES OVER CENTRAL GEORGIA. THINKING IS AS SHORT WAVE LIFTS ACROSS THE REGION...BRINING WITH IT INCREASING UPPER DIVERGENCE AND STEEPENING MID LEVEL LAPSE RATES...MORE ELEVATED CONVECTION WILL BEGIN TO DEVELOP... PARTICULARLY OVER THE ERN HALF OF THE CWFA. THE NAM/S BEST SHOT OF H5 PVA DOESN/T COME THROUGH UNTIL AROUND 0900 UTC WHILE THE RUC IS NOT LOOKING AS ORGANIZED ALOFT AS EARLIER. BOTH MODELS ALSO HAVE THE STRONGEST H5 JET LOCATED MORE ACROSS THE MIDLANDS AND LOW COUNTRY. HOWEVER...IT DOES LOOK LIKE ELEVATED INSTABILITY WL INCRASE QUITE A BIT LATER TNGT...AIDED BY MID LEVEL DRYING AND H5 COLD POOL. DON/T SEE MUCH IN THE WAY OF LLVL CONVERGENCE ON THE MODELS...NOR IS THERE MUCH MOISTURE TRASNPORT. NONE OF THIS LENDS ME A GREAT DEAL OF CONFIDENCE THAT ELEVATED CONVECTION WL BECOME AS WIDESPREAD AS EARLIER THOUGHT. HOWEVER...THERE ARE ENOUGH COMPELLING FACTORS TO LEAVE FORECAST LARGELY INTACT...AND WL LEAVE FLOOD WATCH AS IS. THOUGH I WL CUT BACK ON HEAVY RAIN WORDING IN THE WRN ZONES AND REORIENT POPS TO TRY AND LINE UP A LITTLE BETTER WITH THE NEIGHBORS. && .PREVIOUS DISCUSSION... (ISSUED 250 PM EDT THU JUN 2 2005) SHORT TERM (TONIGHT THROUGH SUNDAY)... VISIBLE SATELLITE IMAGERY NICELY DEPICTS THE WEDGE FRONT AS EXTENDING FROM NEAR CAE TO ATL AND THEN BACK INTO THE SMOKY MOUNTAINS. THE SHORT RANGE MODELS ALL INITIALIZED THE SRN AL CONVECTION QUITE WELL...AND ALL AGREE IN BRINGING THE RESPONSIBLE 500 MB MAIN VORT LOBE UP INTO THE SRN APPALACHIANS AND SENDING THE ASSOCIATED CONVECTIVE DEBRIS NORTHWARD ACROSS THE WESTERN CAROLINAS AND NE GA OVERNIGHT. THIS BECOMES QUITE PROBLEMATIC IN LIGHT OF THE HEAVY RAINFALL OVER THE PAST 36 HOURS. THE HARDEST HIT EASTERN PIEDMONT HAS MANY REPORTS OF 2 TO 4 INCHES OF RAIN FOR THE EVENT THUS FAR. THIS AREA SHOULD ALSO SEE THE BEST COMBINATION OF INSTABILITY AROUND A SLOWLY DECAYING WEDGE...HIGH PRECIPITABLE WATER VALUES...AND A STRONG 850 MB EQUIVALENT POTENTIAL TEMPERATURE AXIS TONIGHT THROUGH TOMORROW. GIVEN THE RECENT HISTORY OF ISOLATED FLOODING...AND THE POTENTIAL FOR ADDITIONAL FLOODING WITH THIS SETUP...WILL ISSUE A FLOOD WATCH FROM ELBERTON TO CHARLOTTE TO SALISBURY THROUGH TOMORROW. MID LEVEL DRYING SHOULD WORK IN FROM THE SW FRIDAY...WITH 850 MB FLOW BECOMING MORE WESTERLY BY FRI NIGHT AS THE TROUGH LIFTS NORTHEAST. WILL CONTINUE TO FAVOR THE COOLER MAV TEMPERATURES FOR ONE MORE DAY AS THE WEDGE SHOULD FINALLY BREAK FRI AFTN. PRECIPITATION CHANCES WILL THEN SHIFT BACK TO THE WESTERN SLOPES THROUGH THE WEEKEND AS A SOUTHEAST RIDGE BUILDS IN OVER THE LINGERING LOW LEVEL MOISTURE. LONG TERM (SUNDAY NIGHT THROUGH THURSDAY)... BACKDOOR COLD FRONT EXPECTED TO MAKE PROGRESS TO THE SOUTH SUNDAY NITE AND MONDAY AS THE UPPER TROF DIGS DOWN OVER THE APPALACHIANS...ERODING WHATEVER IS LEFT OF THE UPPER RIDGE OVER THE SOUTHEAST STATES. HEIGHTS ALOFT FALL UNTIL MAJOR UPPER LOW OVER SOUTHERN CANADA SHIFTS EAST ENOUGH TO ALLOW FOR ANOTHER PERIOD OF SHORTWAVE RIDGING OVER THE REGION. MEANWHILE...CWFA WILL BE SUSCEPTIBLE TO PIECES OF UPPER ENERGY ROTATING OVER THE REGION IN A RATHER MOIST AND UNSTABLE ATMOSPHERE...WITH TEMERATURES PROGD INTO THE UPPER 80S FOR ALL EASTERN ZONES MONDAY...BEFORE COOLING FROM THE NORTH THROUGH MIDWEEK...AND A PERSISTENT CHANCE OF MAINLY AFTERNOON AND EVENING CONVECTION....ESPECIALLY IN THE SOUTHERN ZONES...CLOSER TO EVENTUALLY STALLING POSITION OF THE OLD BACKDOOR FRONT. AVIATION... ANOTHER DIRE TAF PACKAGE WITH PERSISTENT COLD AIR DAMMING...ALTHOUGH WE MAY BEGIN TO SEE EROSION OF THIS FEATURE FROM THE SOUTHWEST AND SOUTHEAST TONITE AND DURING THE OUTLOOK PERIOD. WE FEATURED PERSISTENT NORTHEAST SURFACE WINDS...AND CEILINGS RANGING FROM MVFR... TO IFR DURING CONVECTIVE CELLS. PRECIPITATION SHOULD BECOME WIDESPREAD AT ALL TAF LOCATIONS THIS EVENING AND FOR MOST OF THE OVERNIGHT WITH APPROACH OF A MAJOR SHORTWAVE AND WITH CWFA ENTERING FAVORABLE POSITION RELATIVE TO UPPER JET. VISIBILITIES MAY FALL TO IFR RANGE AT ANY TIME DURING HEAVY RAIN AT ALL THE TAF SITES THROUGH DAYBREAK FRIDAY. OUTLOOK PERIOD FEATURES IMPROVING CONDITIONS...ALTHOUGH THERE WILL BE NUMEROUS SHOWERS REMAINING THROUGH THE CONCLUSION OF THE OUTLOOK PERIOD...WITH VCSH ADVERTISED MOST LOCATIONS AND TEMPO GROUPS INCLUDED TO ACCOUNT FOR ANY RESIDUAL RAIN SHOWERS. PRECIPITATION CHARACTER SHOULD BE SHOWERY...BUT TSRA ADVERTISED AT TIMES OVERNIGHT AT KAND/KCLT...THE TWO TAF SITES MOST SUSCEPTIBLE TO EXPERIENCING PARTIAL OR PERMANENT EROSION OF OUR COLD AIR DAMMING REGIME. && .GSP WATCHES/WARNINGS/ADVISORIES... GA...FLOOD WATCH FOR GAZ029 UNTIL 6 PM FRIDAY. NC...FLOOD WATCH FOR NCZ057-071-072-082 UNTIL 6 PM FRIDAY. SC...FLOOD WATCH FOR SCZ009-011>014-019 UNTIL 6 PM FRIDAY. && $$ SHORT TERM...MCAVOY sc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE ABERDEEN SD 920 PM CDT THU JUN 2 2005 UPDATED ZONES TO BETTER REFLECT WX CONDS AND EXPECTED WEATHER. LATEST GUIDANCE INDICATES THAT BOUNDARY WILL STALL ACROSS ERN SODAK THROUGH THE NIGHT...AND DWPT FRONT HAS LIFT NORTH THROUGH KABR WITH DWPTS RISING INTO THE LOWER 60S BY 02Z. EXPECTED LOWLVL JET TONIGHT MAY AGAIN PROVIDE FOCUS FOR FURTHER DEV OVERNIGHT. CONCERN IS HEAVY RAIN CHCS FOR TRAVERSE COUNTY. THEY RECEIVED FROM 2 TO 5 INCHES OF RAIN EARLIER THIS EVNG. BIG AREA OF CONVECTION ACROSS NCNTRL NEB IS FCSTD TO LIFT NE ACCORDING TO LATEST RUC/M-ETA. REMAINDER OF FCST LOOKS OK. ...PREVIOUS DISCUSSION... .SHORT TERM...TONIGHT THROUGH SUNDAY NIGHT TSRAS DEVELOPING IN NE SD AND WC MN LATE THIS AFTN IN ADVANCE OF SFC FRONTAL BOUNDARY. EXPECT TSRAS TO CONTINUE TO DEVELOP ACROSS THIS AREA THROUGH THE EVENING AND NIGHTTIME HOURS AS UPSTREAM JET STREAK BEGINS TO INFLUENCE THE REGION AND THERE IS PLENTY OF MOISTURE AND INSTABILITY AVAILABLE. OTHERWISE...LARGE UPPER LOW WILL CONTINUE TO WOBBLE AROUND ALONG THE CANADIAN/US BORDER FOR THE NEXT COUPLE DAYS ...WEAKEN AND LIFT INTO CANADA. AFTER TONIGHT...A COUPLE MORE S/WS WILL AFFECT THE EASTERN PART OF THE REGION WHERE PLENTY OF MOISTURE AND INSTABILITY EXISTS. WITH THIS UPPER FLOW...THE BEST CHC FOR TSRAS WILL CONTINUE TO BE ACROSS NE SD AND WC MN THROUGH SAT NIGHT. UPPER RIDGING WILL BUILD INTO THE REGION SUN AND SUN NIGHT. TEMPS WILL BE NEAR NORMAL WITH NOT MUCH WIND THROUGH THE SHORT TERM. .LONG TERM...MONDAY THROUGH THURSDAY MEDIUM RANGE MODELS ARE DOING WELL WITH THE CURRENT PATTERN AND WITH THE EXCEPTION OF THE ECMWF ARE FAIRLY CONSISTENT WITH EACH OTHER. NO BIG CHANGES IN THINKING FROM THE OVERNIGHT PERIOD. MONDAY OPENS WITH AN H5 UPPER LOW DIGGING SOUTH INTO THE SOUTH WEST UNITED STATES WITH AN UPPER RIDGE OVER THIS AREA TILTING NORTHWEST. A SURFACE LOW PRESSURE INVERTED TROUGH IS SETTING UP OVER THE MIDWEST. THERE ARE SEVERAL OLD FRONTAL BOUNDARIES LAYING ACROSS THE REGION. AS THE H5 LOW STARTS TO MOVE EAST THE SURFACE REFLECTIONS WILL LIKELY BE THE FOCUS OF CONVECTION. AS IS USUALLY THE CASE IT IS DIFFICULT TO PREDICT THE PLACEMENT OF THE BAROCLINIC ZONES SO FAR IN ADVANCE. HOWEVER THESE BOUNDARIES WILL FOCUS THE INITIATION OF CONVECTION. FOR THE PRESENT TIME HAVE GONE ALONG WITH NCEP PLACEMENT EXCEPT THAT WILL NOT BRING CONVECTION IN UNTIL TUESDAY AFTERNOON. EXPECT THIS FRONTAL POSITION IS A LITTLE TOO FAR SOUTH. HAVE GONE WITH LARGE AREAS OF THUNDERSTORMS EXPECTING TO WHITTLE AREA DOWN AS TIME APPROACHES. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. && $$ HINTZ/MOHR/KEEFE sd AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY NATIONAL WEATHER SERVICE RAPID CITY SD 810 PM MDT THU JUN 2 2005 .DISCUSSION...STATIONARY FRONT LOCATED ACROSS SOUTH CENTRAL SOUTH DAKOTA. MODERATE THETA-E ADVECTION ACROSS THIS FRONT...WITH SCATTERED CONVECTION. RUC KEEPS AREA OF THETA-E ADVECTION ACROSS THIS AREA THROUGH THE NIGHT..SO HAVE BUMPED UP POPS FOR TONIGHT. ELSEWHERE...SKIES WILL REMAIN PARTLY TO MOSTLY CLOUDY. OVERNIGHT LOWS LOOK GOOD. && .UNR...WATCHES/WARNINGS/ADVISORIES... SD...NONE. WY...NONE. && $$ sd AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY NATIONAL WEATHER SERVICE RAPID CITY SD 300 PM MDT THU JUN 2 2005 .SHORT TERM...WATER VAPOR IMAGERY SHOWING LARGE UPPER LOW NEARLY STATIONARY ACROSS MONTANA/CANADIAN BORDER WITH DEEP SOUTHWESTERLY FLOW ALOFT ACROSS THE REGION. SHORTWAVE CURRENTLY OVER SOURTHERN WYOMING SWINGING AROUND BASE OF THE LOW HAS BEEN GIVING MOST OF THE CWA PLENTY OF THICK CIRROSTRATUS KEEPING AN ALREADY STABLE ATMOSPHERE EVEN MORE SO...PROHIBITING ANY CONVECTION FROM DEVELOPING TODAY. TOWARDS SOUTH CENTRAL SD...STATIONARY FRONTAL BOUNDARY REMAINS A FOCUS FOR CONVECTION INITIATION. VIS SATELLITE SHOWING OUTFLOW BOUNDARY MOVING WEST FROM CORE OF THUNDERSTORM ACTIVITY OVER EASTERN NEBRASKA. THIS OUTFLOW IS WHERE THE STRONG SHOWERS NOW OVER SOUTH CENTRAL SD INITIATED FROM. RUC MODEL TODAY HAS BEEN TRENDING TOWARD LESS FAVORABLE CONDITIONS FOR SEVERE STORMS. WITH CAPE VALUES AT 00Z OF ABOUT 1000 J/KG AND LI VALUES AROUND -3...STILL A FEW ISOLATED SEVERE STORMS POSSIBLE THIS EVENING...BUT BULK OF SEVERE WEATHER ACTIVITY WILL REMAIN EAST OF THE MISSOURI RIVER. FOR FRIDAY...UPPER LOW REMAINS TO OUR NORTH WITH A STRONG SHORTWAVE SWINGING OVER NORTHERN UTAH...BUT AS THE UPPER LOW PHASES IN TO NEXT APPROACHING LOW OVER THE NORTHERN PACIFIC...IT TAKES MORE OF AN EASTERLY TRACK STAYING WELL TO THE SOUTH. SOME THUNDERSTORMS COULD STILL BE SEEN AS HIGHER DEWPOINTS RETURN OVERNIGHT TONIGHT INTO TOMORROW MORNING. MODELS ALSO SUGGESTING THE FRONTAL BOUNADRY NOW OVER SOUTH CENTRAL SD MAY RETROGRADE BACK WEST ALSO INCREASING AREA MOISTURE. EITHER WAY...THERE IS A CHANCE FOR SHOWERS AND STORMS TOMORROW AFTERNOON. FOR SATURDAY AND SUNDAY...A WEAK TROUGH SITS ACROSS THE AREA AS THE NEXT STRONG UPPER LOW PUSHES ONSHORE OVER THE PACIFIC NORTHWEST. A SHORTWAVE TRACKING JUST SOUTH OF THE AREA SATURDAY MAY HELP KICK OFF STORMS AGAIN SATURDAY AFTERNOON. THE TRACK OF THIS WAVE IS STILL UNCERTAIN...SO HAVE DECIDED TO KEEP CHANCE POPS IN FOR NOW. SUNDAY LOOKS LIKE THE BETTER DAY AS WEAK RIDGING BUILDS IN FROM THE WEST...BUT AGAIN WITH DIURNAL HEATING CAN'T RULE OUT THE CHANCE FOR SHOWERS/THUNDERSTORMS SUNDAY AFTERNOON. .LONG TERM...UPPER LOW OVER DAKOTAS WILL SHIFT EASTWARD ON MONDAY WITH UPPER LEVEL RIDGE BUILDING IN. TEMPERATURES WILL BE WELL ABOVE AVERAGE...REACHING THE LOWER TO MID 80S FOR SOUTHERN AND EASTERN ZONES. 12Z GFS SHOWS GOOD INSTABILITY MONDAY AFTERNOON OVER SOUTH DAKOTA...WITH CAPE 2000-3000 J/KG AND LI AT -8 OVER SOUTH CENTRAL SD. CONDITIONS FOR THUNDERSTORMS WILL BE FAVORABLE...WITH SEVERE WEATHER A SIGNIFICANT THREAT. ON TUESDAY...PACIFIC UPPER TROUGH WILL MOVE INTO THE REGION SPREADING MORE THUNDERSTORMS THROUGH THE REST OF THE WEEK. THIS LOOKS LIKE A VERY WET PATTERN FOR THE AREA. 12Z ECMWF AND GFS ARE IN GOOD GENERAL AGREEMENT WITH THIS SITUATION. && .AVIATION...MAINLY VFR CONDITIONS ARE EXPECTED FOR THIS AFTERNOON AND TONIGHT FOR ALL TWEB ROUTES. SCATTERED SHOWERS AND THUNDERSTORMS ARE LOCATED ACROSS WRN NEBRASKA AND SRN CENTRAL SOUTH DAKOTA. ISOLATED THUNDERSTORMS MAY AFFECT TWEB ROUTES...ESPECIALLY TWEB 258. && .UNR...WATCHES/WARNINGS/ADVISORIES... SD...NONE. WY...NONE. && $$ sd AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY NATIONAL WEATHER SERVICE RAPID CITY SD 1030 AM MDT THU JUN 2 2005 .DISCUSSION...CURRENT VIS/WV SHOWING STRONG STATIONARY UPPER LOW ACROSS MONTANA/CANADIAN BORDER WITH DRY SLOTTING CURRENTLY OVER THE CWA. SURFACE ANALYSIS SHOWING DRY COLD FRONT STRETCHING FROM NEAR KSFD TO FAR NORTHEASTERN SD. RADAR SHOWING SHOWERS EXTENDING ALONG FRONTAL BOUNDARY ACROSS SOUTH CENTRAL SD THIS MORNING WITH A BREAK IN THE PRECIP MOVING NORTH FROM NEBRASKA. EXPECT SHOWERS AND THUNDERSTORM COVERAGE TO INCREASE THIS AFTERNOON WITH DAYTIME HEATING DESTABILIZATION OCCURS. LATEST RUC SHOWING CAPE VALUES AT ABOUT 1500 J/KG...LI VALUES AROUND -3...AND NOT MUCH OF A CAP TO BREAK THROUGH. AGREE WITH SPC WITH CURRENT WITH SLIGHT RISK ACROSS MY FAR EASTERN ZONES FOR TODAY. AS FOR THE REST OF THE CWA...LOOKS LIKE ENOUGH DRY AND STABLE AIR WILL REMAIN ACROSS THE AREA TO LIMIT ANY CONVECTION DEVELOPMENT. WITH PROXIMITY OF THE UPPER LEVEL LOW TO THE NORTH AND ASSOCIATED COLD AIR ALOFT...THERE COULD BE SOME SHOWER DEVELOPMENT LATER THIS AFTERNOON ALONG THE SD/WY AND MT BORDER WHERE I'VE PUT IN SLIGHT CHANCE POPS. SHOWERS HAVE ALREADY BEEN MOVING ACROSS EASTERN MONTANA...SO THIS ISN'T OUT OF THE QUESTION. && .UNR...WATCHES/WARNINGS/ADVISORIES... SD...NONE. WY...NONE. && $$ sd AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA NATIONAL WEATHER SERVICE SIOUX FALLS SD 1055 AM CDT THU JUN 2 2005 .DISCUSSION... GOING FCST IS IN PRETTY GOOD SHAPE...HAVE JUST UPLOADED SOME NEW GRIDS FOR THIS AFTN AND TONIGHT FOR MAX/MIN TEMPS...SKY COVER... DEW PTS AND RH. REMNANTS OF MCS STILL MEANDERING THRU ERN NEB ATTM...WITH PLENTY OF STRATUS INVOLVED WITH IT. AT THE HIGHER LEVELS...IMMENSE CS SHIELD HAS ADVECTED NWD INTO THIS AREA FM THE SOUTH. THERE HAS BEEN SOME CLEARING WEST OF THE CS SHIELD IN OUR FAR WRN CWFA...BUT LOOKED AT THE TEMPS ALOFT AND LATEST NAM SNDGS AND IT APPEARS WITH A HIGH DEG OF LOW LVL RH IN OUR WEST AND COOL TEMPS ALOFT...THAT THEY WL SEE SELF DESTRUCTIVE SUNSHINE. SO HIGH TEMPS IN OUR WRN FA ARE VERY TRICKY. THE WARMEST AREA SHOULD BE IN THE SPENCER AND STORM LAKE IA AREA...WHERE THE CS SHIELD WL BE LESS THICK. WL BE WATCHING THE WRN CWFA FOR TS DEVELOPMENT THRU THE AFTN HRS WITH COOL TEMPS ALOFT...AND WL BE RAISING POPS IN OUR CWFA TNGT TO CATEGORICAL...WITH MCS INDUCED SHORTWV MOVG NEWD LATE TONIGHT AND FRI MRNG THRU THE EAST. OVERALL FLOW ALOFT RMNS SW WITH UPPER LOW OVER THE NRN RCKYS...SO IT IS QUITE AN UNSTABLE SITUATION WITH LITTLE OR NO CAPPING. FOR SVR CHCS...DUE TO LACK OF CAPPING WITH COOL TEMPS ALOFT (DESPITE ABUNDANT HIGH CLDS)...WIND PROFILES ARE INDICATING THAT THE BEST CHC FOR SVR TS WL BE IN OUR FAR WRN CWFA LATE THIS AFTN AND EVENING. MODERATE INSTABILITY DOES EXIST THRU MUCH OF THE FA TODAY AND TNGT... BUT NOT ENUF INSTABILITY TO WARRANT ANY MDT OR HIGH RISK OF SVR ATTM. IN FACT...IF WIND PROFILES OFF OF THE NAM AND RUC ARE CORRECT...THEY SHOW QUITE A BIT OF UNI DIRECTIONAL MOTION IN THE LOWEST 2KM THROUGHOUT THE EAST LATE TODAY. THIS IS BACKED UP BY THE 12Z OAX RAOB. THE LBF RAOB WAS RAIN CONTAMINATED. NOTE TO MEDIA...HWO COMING OUT SHORTLY...HOPEFULLY A ZFP TEXT UPDATE AFTER THAT BUT EXTRA TAFS ARE DUE TODAY DUE TO AN OAX BACKUP. SO NO GUARANTEES ON THE ZFP TEXT UPDATE. FOR QUICKER UPDATES...CHECK OUT OUR GRIDS. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. IA...NONE. NE...NONE. && $$ MJF sd AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SPOKANE WA 845 AM PDT THU JUN 2 2005 .SYNOPSIS...A COOL...UNSETTLED WEATHER PATTERN WILL LINGER OVER THE INLAND NORTHWEST THE REMAINDER OF THE WEEK. AS SUCH EXPECT OCCASIONALLY WET SPRING TIME WEATHER AND COOLER THAN NORMAL TEMPERATURES. && .UPDATE...TODAY...UPDATING THE EASTERN AND MAINLY THE SOUTHEAST ZONES TODAY TO INCREASE POPS. WRAP AROUND MOISTURE MOVING THROUGH THE REGION...COMBINED WITH ISENTROPIC LIFT HAS ALREADY BROUGHT AMPLE PRECIPITATION TO THE PANHANDLE ZONES WEST INTO THE SPOKANE AREA. THIS MOISTURE IS MOVING SOUTH TOWARDS THE SOUTHERN PALOUSE AND INTO THE BLUE MOUNTAINS OF WASHINGTON. AS SUCH BUMPED UP POPS TO CATEGORICAL FOR THESE ZONES. EXPECT SOME CLEARING AFTER 20-21Z FROM THE NORTHEAST AS THIS MOISTURE BEGINS TO CLEAR THE AREA. HIGHER DEWPOINTS AND INSOLATION SHOULD DESTABILIZE THE ATMOSPHERE ENOUGH TO SUPPORT AFTERNOON CONVECTION AND ISOLATED THUNDERSTORMS. RUC 40 IS INDICATING CAPES NEAR 200J/KG AND LI'S -2 TO -4. IN ADDITION WILL BRING DOWN TEMPERATURES IN THE AREAS THAT ARE RECEIVING PRECIPITATION. ON THE OTHER HAND...THE EAST SLOPES OF THE CASCADES HAVE BEEN RECEIVING DOWN SLOPING FLOW AND MAINLY CLEAR SKIES. EXPECT INCREASING UPPER LEVEL CLOUDS TO MOVE IN THAT AREA THROUGH EARLY AFTERNOON...BUT EXPECT ONLY ISOLATED SLOP OVER SHOWERS ALONG THE CASCADE CREST TODAY. /TOBIN .AVIATION...IFR CEILINGS AND LIGHT RAIN WITH MOUNTAIN OBSCURATION WILL CONTINUE OVER THE IDAHO PANHANDLE AND EXTREME EASTERN WASHINGTON THROUGH ABOUT 20Z TODAY. CONDITIONS WILL IMPROVE TO VFR OR MVFR BEGINNING IN THE NORTH AND SPREAD THROUGH THE AFTERNOON. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS WILL DEVELOP OVER THE NORTHERN MOUNTAINS THIS AFTERNOON. && .PRELIMINARY POINT TEMPS/POPS... SPOKANE 61 45 66 45 69 45 / 100 10 20 10 10 10 COEUR D'ALENE 59 44 64 46 67 46 / 100 30 20 10 10 10 PULLMAN 57 42 62 43 67 43 / 100 20 20 10 10 10 LEWISTON 63 49 67 50 74 50 / 80 40 20 10 10 10 COLVILLE 64 45 68 45 72 45 / 80 20 40 20 30 20 SANDPOINT 59 44 63 45 68 45 / 100 30 40 20 30 20 KELLOGG 57 43 63 44 68 44 / 100 50 40 20 30 20 MOSES LAKE 73 49 74 48 77 48 / 10 10 10 10 10 10 WENATCHEE 72 51 74 51 75 51 / 10 10 10 10 10 10 OMAK 68 46 72 47 75 47 / 20 10 10 10 10 10 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...NONE. WA...NONE. && $$ wa FLORIDA KEYS AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE KEY WEST FL 437 AM EDT FRI JUN 3 2005 .DISCUSSION... .OBSERVATIONS/TRENDS... LATEST GOES-12 MOISTURE CHANNEL IMAGERY DEPICTS A SHARP MID/UPPER- TROPOSPHERIC TROUGH ORIENTED NORTH-SOUTH ACROSS THE GULF OF MEXICO AND EXTREME NORTHWEST CARIBBEAN BASINS. OF PARTICULAR INTEREST IS A SHORT WAVE TROUGH EVIDENT MOVING NORTH ACROSS THE NORTHWEST CARIBBEAN BETWEEN THE CAYMAN ISLANDS AND THE YUCATAN PENINSULA. THE FLORIDA KEYS LIE EAST OF THE LARGE-SCALE TROUGH AXIS AND NORTH OF THE APPROACHING SHORT WAVE TROUGH...WITHIN DEEP...VERY MOIST...AND FAIRLY STRONG SOUTHERLY FLOW. SOUTH WINDS ARE AVERAGING 35KT IN THE 850-700MB LAYER ACCORDING TO THE LAST FEW HOURS OF DOPPLER VAD WIND PROFILE MEASUREMENTS. LATEST DOPPLER RADAR SCANS SHOW NUMEROUS PATCHES OF LIGHT RAIN...AND SCATTERED HEAVY RAIN SHOWERS WITH A FEW THUNDERSTORMS OVER THE WATERS BETWEEN KEY WEST AND THE DRY TORTUGAS. RUC ANALYSES SUGGEST THAT THE ATMOSPHERE OVER THE KEYS AND ADJOINING WATERS HAS DESTABILIZED SINCE THURSDAY EVENING -- THIS IS CONSISTENT WITH THE DEEP...LARGE-SCALE ASCENT THAT APPEARS TO BE ONGOING ACROSS MUCH OF THE SERVICE AREA...AS WELL AS WESTERN CUBA...AND ADJACENT GULF AND CARIBBEAN WATERS. .FORECASTS... AT LEAST ONE EPISODE OF MEASURABLE RAINFALL APPEARS ALMOST CERTAIN ACROSS THE FLORIDA KEYS AND ADJOINING WATERS TODAY...AND THUS OUR 12-HOUR PRECIPITATION PROBABILITY IS 90 PERCENT. CONVECTIVE CELLS WILL BE MOVING RAPIDLY...WITH A FORWARD MOVEMENT AVERAGING NEAR 30KT. SOME GUSTY WINDS WILL BE LIKELY WITH THE MORE INTENSE SHOWERS AND THUNDERSTORMS...ALTHOUGH A NEARLY SATURATED LOWER TROPOSPHERE SHOULD KEEP THE CAP ON CONVECTIVE WIND GUSTS NEAR 45KT. THE 03/00Z GFS DEVELOPS AN OBVIOUSLY SPURIOUS WARM-CORE CYCLONIC CIRCULATION IN THE LOWER TROPOSPHERE OVER THE SOUTHEASTERN GULF OF MEXICO BY SUNSET...PROBABLY RENDERED BY UNREALISTIC MODEL GRID-SCALE CONVECTIVE FEEDBACK. THE GFS LARGE-SCALE DEPICTIONS APPEAR GENERALLY REASONABLE...WITH THE SPURIOUS CYCLONE THE GLARING EXCEPTION. IT APPEARS FROM A CONSIDERATION OF ALL NWP OUTPUT THAT THE SHARP UPPER TROUGH WILL SLOWLY MOVE EAST WHILE DAMPENING OUT. THIS MEANS THAT DEEP...MOIST...AND UNSTABLE SOUTHERLY FLOW WILL PERSIST FOR AT LEAST A DAY OR TWO...ALONG WITH HIGHER-THAN-AVERAGE RAIN CHANCES. AN ATLANTIC RIDGE OF HIGH PRESSURE WILL LIKELY SET UP ACROSS CENTRAL OR SOUTH FLORIDA BY SUNDAY NIGHT...AND PERSIST FOR MOST OF NEXT WEEK. HIGH BOUNDARY-LAYER MOISTURE AND THE ABSENCE OF A WELL-DEFINED MID-LEVEL RIDGE OVER THE AREA SUGGEST THAT THE INHERITED HIGHER-THAN CLIMO POPS ARE REASONABLE. && .MARINE... OCCASIONAL FAST-MOVING SHOWERS AND A FEW THUNDERSTORMS WILL AFFECT THE FLORIDA KEYS AND SURROUNDING WATERS TODAY. MAINLY SOUTHEAST BREEZES WILL AVERAGE NEAR 15KT. HOWEVER...STRONGER AND GUSTY WINDS ARE LIKELY IN AND NEAR SHOWERS AND THUNDERSTORMS...WITH STRONGER SHOWERS AND STORMS DELIVERING WIND GUSTS NEAR GALE FORCE. STAY TUNED TO NOAA WEATHER RADIO OR THE VHF WEATHER BAND FOR THE LATEST SHORT TERM FORECASTS...STATEMENTS...AND POSSIBLE MARINE WARNINGS. && .AVIATION... FLYING CONDITIONS WILL BEGIN TO DETERIORATE THROUGH THE MORNING ALONG THE KMIA-KEYW FLIGHT ROUTE...INCLUDING THE KMTH AND KEYW TERMINALS. LIGHT STRATIFORM RAIN WILL INCREASE IN COVERAGE BY 12Z. SCATTERED SHOWERS WITH ISOLATED HEAVIER THUNDERSTORMS WILL BEGIN TO DEVELOP AFTER SUNRISE...LOWERING FLYING CONDITIONS TO MVFR IN SHOWERS AND IFR AND POSSIBLY EVEN LIFR IN THUNDERSTORMS FOR INTERMITTENT PERIODS. HEAVIER SHOWERS AND THUNDERSTORMS MAY ALSO PRODUCE SURFACE WIND GUSTS IN EXCESS OF 30 KNOTS FROM THE SOUTH. SURFACE WIND AT THE KEYS TERMINALS WILL AVERAGE SOUTHEAST AT 7-12 KNOTS THROUGH THE DAY. WHEN PLANNING YOUR FLIGHT...PLEASE CHECK THE LATEST OBSERVATIONS... SIGMETS/AIRMETS...AND FORECASTS. YOUR PIREPS ARE APPRECIATED. && .PRELIMINARY POINT TEMPS/POPS... KEY WEST 85/79/88/80/89 90/60/50/40/40 MARATHON 85/79/88/80/89 90/60/50/40/40 && .EYW WATCHES/WARNINGS/ADVISORIES...NONE. $$ K. KASPER L. KASPER fl AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 405 AM EDT FRI JUN 3 2005 .SHORT TERM...TODAY AND TONIGHT MODELS IN REASONABLE AGREEMENT DEPICTING 500 MB OHIO VALLEY LOW/VORTICITY MAXIMUM...INITIALIZED PRETTY WELL AS PER WATER VAPOR IMAGERY...LIFTING SLIGHTLY NORTHEAST TODAY BEFORE GETTING NUDGED EAST TONIGHT AS SHORTWAVE RIDGE BUILDS OVER FORECAST AREA. SATELLITE IMAGERY DEPICTS WEAK DEFORMATION AREA OVER SOUTHERN MI...SHOWN BY MODELS LIFTING NORTH TODAY AND WEAKENING FURTHER. AT THE SURFACE...RIDGE OVER NORTHERN AND EASTERN GREAT LAKES REGION SLOWLY RETREATING EAST THROUGH TONIGHT...AS WEAK LOW OVER WESTERN OHIO VALLEY WEAKENS/DISSIPATES. DEEPER MOISTURE...AS PER 850 TO 500 MB...MODEST BEFORE DWINDLING LATE TODAY AND TONIGHT. 925 MB MOISTURE REMAINING QUITE GOOD ON THE OTHER HAND. SYNOPTIC SCALE LIFT VERY LIMITED AT BEST THROUGH TONIGHT. OCCASIONAL VERY WEAK LOW TO MID LEVEL OMEGA LIFT AT MOST...A LITTLE WEAK DEFORMATION IN AREA TODAY AS NOTED ABOVE. 300K TO 305K NAM AND GFS ISENTROPIC ASCENT ABSENT THROUGH TONIGHT...DESPITE SUITABLY LOW CONDENSATION PRESSURE DEFICITS TODAY. WILL MENTION CHANCE OF LIGHT RAIN SHOWERS TODAY AND CHANCE OF SPRINKLES CENTRAL AND SOUTH THIS EVENING. HIGHER DEW POINTS AND LIGHT WINDS TONIGHT WILL FAVOR MENTION OF PATCHY FOG LATE TONIGHT. GUIDANCE TEMPERATURES LOOK TO BE IN THE BALLPARK...KEPT LOWER TODAY DUE TO CLOUD COVER. THOUGH K INDICES CLOSE TO 30 THROUGH TONIGHT...LIFTED INDICES AND CAPES PORTRAY RATHER STABLE OVERHEAD..THUS NO THUNDER WILL BE MENTIONED. && .LONG TERM... BROAD SOUTHWESTERLY UPPER FLOW CONTINUES ACROSS THE CENTRAL CONUS ON SATURDAY...BETWEEN RIDGE OVER THE LOWER GREAT LAKES AND TROUGH OVER THE HIGH PLAINS. SHORTWAVES CURRENTLY OVER THE NEVADA AND NORTHERN MEXICO WILL SWING THROUGH THE CENTRAL PLAINS AND TOWARD THE GREAT LAKES. 00Z NAM IS A TOUCH SLOWER AND THE 00Z GFS IS A TOUCH FASTER BRINGING THE SYSTEMS INTO THE GREAT LAKES. BASED ON EARLIER MODEL TRENDS...RECENT ONES ARE NOT TOO DIFFERENT...WITH MODELS LATCHING ONTO MORE OF A SOLID SOLUTION. GOOD/DEEP MOISTURE ADVECTION INTO SOUTHEAST MICHIGAN BY SATURDAY EVENING. SOME LIFT PRESENT FROM WARM/MOIST ON SATURDAY...WITH INCREASING INSTABILITY. OVERALL SETUP STILL LOOKS BORDERLINE FOR PRECIP ON SATURDAY...AND WILL LEAVE CURRENT MENTION OF SLIGHT CHANCE DURING THE AFTERNOON. BETTER SHOT FOR PRECIP ON SATURDAY NIGHT WITH MOISTURE IN PLACE AND BETTER LIFT SEEN WITH INCREASING 850-500MB QVECTOR CONVERGENCE AHEAD AN UPPER SHORTWAVE. WILL ALSO BUMP TEMPS UP A TOUCH ON SATURDAY GIVEN A FAIR AMOUNT OF INSOLATION...AND A FEW DEGREES MORE SATURDAY NIGHT GIVEN AMOUNT OF LOW-LEVEL MOISTURE IN PLACE. SUNDAY COULD PROVE TO BE INTERESTING AS FAR AS SEVERE WEATHER POTENTIAL GOES. BETTER-DEFINED SHORTWAVE TROUGH LIFTS THROUGH THE GREAT LAKES...WITH ADDITIONAL MODEL DIFFERENCES. GFS IS FARTHER NORTH AND STRONGER WITH THE MAIN LOW...LIKELY DUE TO CONVECTIVE FEEDBACK PRESENT EARLIER. NAM KEEPS THE TROUGH FARTHER SOUTH...AND FOCUSES THE STRONGEST HEIGHT FALLS ACROSS LOWER MICHIGAN SUNDAY AFTERNOON/EVENING /AS OPPOSED TO NORTHERN ONTARIO PER THE GFS/. LOCAL WRF-XX HAS A MUCH STRONGER SHORTWAVE LIKE THE GFS...BUT IS FARTHER SOUTH LIKE THE NAM. IN ADDITION TO STRONG HEIGHT FALLS AND DEEP MOISTURE PRESENT FROM EARLIER THETA-E ADVECTION /MODEL DEPICTIONS OF PRECIPITABLE WATERS OVER 1.5 INCHES/...WIND FIELD ALSO INCREASES WITH A +35KT 850MB JET ACCOMPANYING THE STRONG HEIGHT FALLS. THE UPPER-LEVEL JET IS NOT TOO STRONG /60-70KTS/...BUT THE NAM/WRF-XX POSITION PLACES SOUTHEAST MICHIGAN IN THE RIGHT-ENTRANCE REGION WITH FAVORABLE UPPER DIVERGENCE. WITH DEWPOINTS CLIMBING INTO THE MID 60S...SB-CAPES IN BOTH THE NAM/WRF-XX EXCEED 2000J/KG. WITH THE HIGHER TEMPORAL RESOLUTION THE NAM12 YOU CAN SEE THAT IT DEVELOPS TWO WAVES OF PRECIPITATION...ONE EARLY MORNING ALONG THE MOIST AXIS AND ONE DURING THE LATE AFTERNOON AHEAD OF THE SURFACE FRONT. THIS SETUP SEEMS PRETTY REASONABLE. GIVEN THE VARYING DEGREES OF UNCERTAINTY WILL JUST MENTION CHANCE TSRA...BUT INCLUDE THE POSSIBILITY OF SEVERE WEATHER IN THE HWO. ADDITION TIMING/INTENSITY DIFFERENCES PERSIST THROUGH SUNDAY NIGHT/MONDAY. THE MUCH STRONGER WRF-XX IS THE SLOWEST TO CLEAR THE SHORTWAVE TROUGH /ACTUALLY NEARLY A COMPACT CUTOFF LOW BY SUNDAY NIGHT/ THROUGH THE CWA. GENERAL TROUGHING REMAINS ACROSS THE REGION THROUGH MONDAY...UNTIL HIGH PRESSURE BUILDS IN BY MONDAY NIGHT. INSTABILITY IS WEAK BUT PRESENT...AND GIVEN LINGERING LIFT/CONVERGENCE WILL KEEP CHANCE POPS GOING ON MONDAY. HOWEVER FOR MONDAY NIGHT THROUGH TUESDAY NIGHT WILL DROP POPS GIVEN GENERAL CONSENSUS SHOWING HIGH PRESSURE MORE IN CONTROL ACROSS THE REGION. IN ADDITION WILL KEEP WEDNESDAY/THURSDAY DRY AT THIS POINT. WHILE THERE CONTINUES TO BE A LARGE DEGREE OF SPREAD IN THE EXTENDED MODEL SOLUTIONS...IT APPEARS THAT A FRONT WILL SWING THROUGH OR SETUP ACROSS SOUTHEAST MICHIGAN DURING THIS TIME PERIOD. HOWEVER GIVEN THE VARIABILITY AND DISAGREEMENT BETWEEN SOLUTIONS...WILL HOLD ONTO THE CURRENT FORECAST FOR NOW. && .AVIATION...105 AM EDT FRI JUN 3 2005 VERY LIGHT SHOWERS/SPRINKLES CONTINUE TO LIFT NORTH ACROSS SE MICHIGAN AHEAD OF SOME LOW LEVEL MOISTURE ADVECTION. TIMING OF MVFR CEILINGS INTO THE TAF SITES WILL BE THE MAIN CHALLENGE THIS TAF SET. THE 00Z MESO SCALE MODELS NOW HAVE A LITTLE BETTER HANDLE ON THE LOW LEVEL MOISTURE. BASED ON THE 00Z RUC/NAM AND OBSERVATIONS UPSTREAM... WILL DELAY THE ONSET OF WIDESPREAD MVFR CEILINGS A COUPLE OF HOURS FROM PREVIOUS TAF SET. IT ALSO APPEARS FROM THE LATEST GUIDANCE AND LOOKING UPSTREAM THAT CIGS IN THE 1K TO 2K FOOT RANGE WILL LIFT JUST WEST OF THE TAF SITES. SO PRIMARILY EXPECTING CIGS OF 2K TO 3K FEET TO OVERSPREAD THE AREA BY 12Z. SURFACE DEWPOINTS HAVE BEEN STEADILY RISING THE LAST FEW HOURS... ESPECIALLY SOUTH OF I 94 WHERE DEWPOINTS ARE ALREADY AROUND 60. BY MORNING... THINK THESE HIGH DEWPOINTS WILL RESULT IN SOME REDUCED VISIBILITY IN HAZE AROUND DETROIT. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...NONE. LAKE ST CLAIR...NONE. MI WATERS OF LAKE ERIE...NONE. && $$ DWD/BRAVENDER mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 105 AM EDT FRI JUN 3 2005 .AVIATION... VERY LIGHT SHOWERS/SPRINKLES CONTINUE TO LIFT NORTH ACROSS SE MICHIGAN AHEAD OF SOME LOW LEVEL MOISTURE ADVECTION. TIMING OF MVFR CEILINGS INTO THE TAF SITES WILL BE THE MAIN CHALLENGE THIS TAF SET. THE 00Z MESO SCALE MODELS NOW HAVE A LITTLE BETTER HANDLE ON THE LOW LEVEL MOISTURE. BASED ON THE 00Z RUC/NAM AND OBSERVATIONS UPSTREAM... WILL DELAY THE ONSET OF WIDESPREAD MVFR CEILINGS A COUPLE OF HOURS FROM PREVIOUS TAF SET. IT ALSO APPEARS FROM THE LATEST GUIDANCE AND LOOKING UPSTREAM THAT CIGS IN THE 1K TO 2K FOOT RANGE WILL LIFT JUST WEST OF THE TAF SITES. SO PRIMARILY EXPECTING CIGS OF 2K TO 3K FEET TO OVERSPREAD THE AREA BY 12Z. SURFACE DEWPOINTS HAVE BEEN STEADILY RISING THE LAST FEW HOURS... ESPECIALLY SOUTH OF I 94 WHERE DEWPOINTS ARE ALREADY AROUND 60. BY MORNING... THINK THESE HIGH DEWPOINTS WILL RESULT IN SOME REDUCED VISIBILITY IN HAZE AROUND DETROIT. && .UPDATE... ONLY REAL UPDATE NEEDED TO THE FORECAST PACKAGE TONIGHT IS TO CARRY SCATTERED LIGHT SHOWERS ALONG AND SOUTH OF M 59 BASED ON THE RADAR COVERAGE AND TO EXTEND THE CHANCE OF LIGHT SHOWERS NORTH ACROSS THE ENTIRE SAGINAW VALLEY AND THUMB OVERNIGHT. BASED ON THE 00Z UPPER AIR DATA... THE 12Z AND 18Z NCEP SUITE DID NOT HAVE A GOOD HANDLE ON MOISTURE ACROSS THE NORTHERN OHIO VALLEY AND SOUTHERN GREAT LAKES. AREA RADAR DATA HAS ALREADY BEEN SHOWING RETURNS OVER FAR SE MICHIGAN WITHIN A WELL DEFINED 700MB THETA E RIDGE. A STRONG MOISTURE GRADIENT WAS ALSO PRESENT NEAR 850MB ACROSS THE FAR SOUTHERN PORTIONS OF THE STATE. THIS LOW LEVEL MOISTURE WILL WORK ITS WAY NORTH DURING THE NIGHT. MEANWHILE... THE 00Z RAOBS ALSO SUGGEST A LITTLE STRONGER UPPER JET OVER NORTHERN LOWER MI AND LAKE HURON... WITH 250MB WINDS OF 50KTS AT APX. THIS ALONG WITH SOME MID LEVEL DEFORMATION IS LIKELY ENHANCING MID LEVEL LIFT... WHICH HAS LED TO A PERSISTENT BAND OF -RA FROM SW LOWER MI TO CHICAGO. THE COMBINATION OF LOW AND MID LEVEL MOISTURE ADVECTION LIFTING IN FROM THE SOUTH ALONG WITH SOME MID LEVEL LIFT CERTAINLY WARRANTS THE SCATTERED/CHANCE POPS TONIGHT. SOME LIMITING FACTORS FOR NOT RAISING POPS TONIGHT WOULD BE THE DRY LOW LEVEL AIR THAT STILL HAS TO BE OVERCOME... ESPECIALLY IN THE SAGINAW VALLEY... AND FAIRLY SHALLOW LAPSE RATES ALOFT BASED OFF AREA SOUNDINGS WHICH SHOULD LIMIT ELEVATED INSTABILITY. && .SHORT TERM...THURSDAY NIGHT AND FRIDAY UPPER LEVEL LOW OVER NORTHERN ALABAMA WILL SLOWLY MOVE NORTHEAST TOWARDS THE APPALACHIANS OVERNIGHT AND FRIDAY. THIS LOW WILL HELP FORCE THE SURFACE HIGH OFF THE EAST COAST FARTHER OFFSHORE ALLOWING FOR PRESSURE FALLS ACROSS MICHIGAN ON FRIDAY. THE MAIN FORECAST CONCERN FOR TONIGHT IS THE CHANCE AND COVERAGE OF LIGHT RAIN SHOWERS SPREADING NORTH OVER THE AREA. THESE SHOWERS HAVE GRADUALLY SPREAD ACROSS NORTHERN INDIANA AND SOUTHWEST OHIO THROUGH THE AFTERNOON. PREFER THE GFS FOR THIS EVENING AS IT SEEMED TO HAVE A BETTER HANDLE THAN NAM WITH BOTH THE AMOUNT OF MID-LEVEL DRY AIR OVER MICHIGAN AND NORTHEAST OHIO AND THE COVERAGE OF QPF THIS AFTERNOON. THIS AREA OF PRECIP HAS BEEN SPREADING NORTH ALONG A VORT LOBE THAT EJECTED OUT OF THE UPPER LOW THIS MORNING AND WILL CONTINUE ACROSS SE MICHIGAN THIS EVENING. DESPITE THIS LOBE WEAKENING...LOOKS LIKE THE BEST PERIOD FOR SHOWERS WILL BE FROM ABOUT 9PM-3AM WITH A DECENT AREA OF MID-LEVEL DEFORMATION SETTING UP OVER SOUTHERN LOWER MICHIGAN. AS WE HEAD INTO FRIDAY...THE AREA OF WEAK LOW PRESSURE OVER THE LOWER MISSISSIPPI RIVER VALLEY WILL OPEN AND MOVE NORTH SETTING UP AS A TROUGH STRETCHING FROM CENTRAL ILLINOIS TO CENTRAL OHIO. THIS IS ALL OUT AHEAD OF A BROAD AREA OF LOW PRESSURE APPROACHING FROM THE PLAINS. THIS SURFACE TROUGH WILL ACT AS A WEAK CONVERGENT BOUNDARY FOR SHOWERS TO DEVELOP ALONG ON FRIDAY AFTERNOON. WITH PLENTY OF LOW LEVEL MOISTURE AND A THETA-E RIDGE SNEAKING INTO SW MICHIGAN WILL LEAVE LOW CHANCE OF SHOWERS IN ACROSS FAR SOUTHWESTERN COUNTIES TAPERING TO SPRINKLES ELSEWHERE ACROSS THE AREA. && .LONG TERM...FRIDAY NIGHT THROUGH THURSDAY DIFFICULT FORECAST AS A NUMBER OF SHORTWAVES RIDE INTO THE GREAT LAKES IN THE SOUTHWEST UPPER LEVEL FLOW AS UPPER PATTERN REMAINS LARGELY IN A WESTERN TROF/EASTERN RIDGE CONFIGURATION. BY NEXT WEEK...THIS PATTERN IS PROGGED TO UNDERGO A TEMPORARY CHANGE AS SHORTWAVE ENERGY EDGES ACROSS SOUTHEASTERN CANADA...ALLOWING THE RIDGE TO RE-CENTER OVER THE MIDWEST/PLAINS FOR A FEW DAYS. THIS TREND WILL FURTHER COMPLICATE THE FORECAST...BOTH IN TERMS OF RAIN CHANCES AND TEMPERATURES. BEFORE THAT THOUGH...WE WILL HAVE TO DEAL WITH THE SHORTWAVE OVER THE BAJA TODAY...WHICH IS PROGGED TO RIDE UP SOUTHWEST FLOW INTO THE LAKES BY LATE SATURDAY. WATER VAPOR IMAGERY HAS A NICE DEPICTION OF THIS SYSTEM...WHICH IS RATHER LARGE AND FAIRLY WELL FORMED ATTM. IT WILL BE VERY DIFFICULT TO ASCERTAIN HOW WELL THIS WAVE WILL SURVIVE AS IT TRACKS TOWARD THE AREA. THE UPPER LOW TO OUR SOUTH TODAY WILL ACTUALLY HELP OUT AS IT LAYS OUT A DIFFLUENT UPPER FLOW FROM THE AR-LA-TEX TO OHIO VALLEY...WHICH IN ALL LIKELIHOOD WILL HELP THE SOUTHWESTERN SHORTWAVE MAINTAIN ITSELF. WITH THIS IN MIND...WILL ADJUST FORECAST SLIGHTLY AND UP THE CHANCE OF SHOWERS/THUNDERSTORMS BY SATURDAY EVENING (AT THE SAME TIME DELAYING THE ONSET BY 6-12 HRS). AT THE SAME TIME...DRY AIR WILL EAT AWAY AT THE MOISTURE AS IT ADVECTS INTO THE AREA...SO WILL GO NO MORE THAN 30% CHANCE. IN THE WAKE OF THIS SYSTEM...THE REAL DIFFICULTY BEGINS...AS MESO AND STORM SCALE FORCING BECOME MORE AND MORE INFLUENTIAL IN THE PLACEMENT OF BEST THUNDERSTORM CONCENTRATIONS. THE FIRST EXAMPLE OF THIS COMES ON SUNDAY AS NAM LAYS OUT THE BEST FOCUS FOR TSRAS SOUTH OF THE AREA IN BEHIND THE SATURDAY NIGHT ACTIVITY...AS DOES THE LOCALLY RUN WRFXX. HOWEVER...GFS DOES NOT DO THIS...NOR DOES AN EXTRAPOLATION OF PSU MM5. GIVEN THE EXPECTATION THAT THE SATURDAY EVENING "EVENT" WILL BE OF A RATHER LIMITED SCOPE...WILL KEEP THE CURRENT MENTION OF THUNDER IN ON SUNDAY...ASSUMING THERE WILL NOT BE A COMPLEX STRONG ENOUGH TO DISPLACE THE LOW LEVEL FORCING TOO FAR SOUTH OF CWA...FOR TOO LONG. DO NOT FEEL CONFIDENT ENOUGH TO CHANGE ANYTHING IN THE FORECAST FROM MONDAY ON THROUGH THE REST OF THE FORECAST. THE TREND SHOULD BE TO SLOWLY DISPLACE THE BEST CHANCE OF PRECIPITATION FURTHER AND FURTHER SOUTH AS UPPER WAVES LUMBERS ACROSS SOUTHEAST CANADA...AND ALLOWS HIGH PRESSURE TO NOSE SOUTH THROUGH THE LAKES. THE CURRENT FORECAST HAS THIS BASIC TREND IN PLACE...AND CANNOT FIND ANY GOOD REASON TO DISAGREE. TEMPERATURES...IN THE MEANTIME...WILL BE DEPENDENT ON THE LOCATION AND TIMING OF SHOWER/THUNDERSTORM CLUSTERS...WITH A COOLING TREND EARLY NEXT WEEKEND FROM AFOREMENTIONED CANADIAN SYSTEM AND HIGH PRESSURE. DO NOT PLAN ON ANY BIG CHANGES WITH HIGHS/LOWS BOTH BY AND LARGE TO HOLD AOA CLIMO THROUGH MONDAY (80SISH/60ISH)...WHICH IS MORE OR LESS THE MIDDLE GROUND BETWEEN SUNNY -VS- CLOUDY/RAINY. THIS...PARTICULARLY TRUE FOR THE DAYTIME. AFTER A "SPEED BUMP" IN THE TUE/WED TIME-FRAME...RIDGE AXIS IS PROGGED TO MIGRATES BACK EAST INTO THE GREAT LAKES...BRINGING ANOTHER MODERATION BACK TOWARD THAT 80/60 DAY/NIGHT REGIME. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...NONE. LAKE ST CLAIR...NONE. MI WATERS OF LAKE ERIE...NONE. && $$ AVIATION/UPDATE.....CONSIDINE SHORT TERM...KAHL LONG TERM....GURNEY mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SPRINGFIELD MO 400 AM CDT FRI JUN 3 2005 .DISCUSSION... APOLOGIZE FOR THE LATE AND LONG AFD...BUT LOTS TO EXAMINE AND TALK ABOUT THIS MORNING... TIS THE SEASON OF MCS'S. LARGE MCS OVER NEBRASKA CONTINUES TO MARCH EASTWARD WITH THE TAIL END OF THE MCS BEGINNING TO LAY OUT ACROSS NORTH CENTRAL KANSAS. THE PROGRESSIVE NORTHERN PORTION OF THE MCS IS ABOUT TO RUN OUT OF INSTABILITY AND WILL LIKELY WEAKEN RAPIDLY AS IT MOVES INTO WESTERN IOWA AND NORTHWEST MISSOURI. SPC MESOANALYSIS PAGE SHOWS THAT THE EASTERN EXTENT OF THE INSTABILITY EXTENDS ABOUT AS FAR EASTWARD AS THE KANSAS MISSOURI BORDER...AND EVEN THERE MUCAPES ARE <750 J/KG. CORFIDI VECTORS FROM THE RUC AND NAM BOTH INDICATE THAT A TURN TO ALMOST DUE SOUTH WILL OCCUR WITH TAIL END OF THE MCS THIS MORNING...AND THIS WOULD SEEM TO MAKE SENSE GIVEN THE NORTH TO SOUTH ORIENTED INSTABILITY AXIS. GIVEN THE SHARP N/S INSTABILITY AXIS DECIDED TO KEEP A SHARP EAST/WEST POP GRADIENT ACROSS THE CWA TODAY WITH RAIN VERY UNLIKELY OVER THE FAR EASTERN OZARKS TODAY AS THIS MCS RAPIDLY WEAKENS AS IT MOVES EASTWARD. NOW THIS MCS IS OUR MOST IMMEDIATE CONCERN...BUT IT IS FAR FROM THE ONLY CONCERN. VIGOROUS SHORTWAVE IS LIFTING NORTHEAST ACROSS THE RIO GRAND VALLEY AREA OF SOUTHWEST TEXAS. CONVECTION ASSOCIATED WITH THAT SHORTWAVE IS CURRENTLY MORPHING INTO ANOTHER MCS. IT APPEARS AS THOUGH THE BRUNT OF THIS MCS WILL MOVE MORE EAST THAN NORTHEAST...WHICH IS SUPPORTED BY CORFIDI VECTORS AND 850-300MB THICKNESS. THE SYNOPTIC SCALE SHORTWAVE RESPONSIBLE FOR THIS CONVECTION MOVE NORTHEAST INTO OKLAHOMA THIS AFTERNOON...HOWEVER THE SURFACE BOUNDARY WILL PROBABLY REMAIN FURTHER WEST ACROSS THE PANHANDLE REGION NORTHWARD INTO CENTRAL KANSAS. WITH UPPER SUPPORT REALLY NOT JUXTAPOSED WITH SURFACE BOUNDARY THIS AFTERNOON IT IS DIFFICULT TO PINPOINT OR EVEN MAKE A GOOD GUESS AT CONVECTIVE INITIATION...ESPECIALLY GIVEN THE SOUTHWARD MOVING MCS OVER KANSAS. GIVEN THE LARGE SCALE SUPPORT FOR CONVECTION IT SEEMS LIKELY THAT THE CURRENT MCS OVER NORTHERN KANSAS WILL EITHER SURVIVE INTO THE AFTERNOON AND RE-INTENSIFY...OR LEAVE BEHIND AN OUTFLOW BOUNDARY THAT WILL BE THE FOCUS FOR A NEW BATCH OF CONVECTION OVER OK/KS THIS AFTERNOON AS LARGE SCALE ASCENT INCREASES AHEAD OF THE APPROACHING SHORTWAVE. STILL APPEARS AS THOUGH THE AXIS OF MAXIMUM INSTABILITY WILL REMAIN WEST OF OUR CWA...PROBABLY INCHING INTO OUR WESTERN COUNTIES THIS AFTERNOON AS EASTERLY LOW LEVEL FLOW CONTINUES TO RETARD NORTHWARD ADVECTION OF MOISTURE. BEST GUESS NOW IS THAT STRONG/POTENTIALLY SEVERE CONVECTION WILL FORM OVER OK/KS THIS AFTERNOON AND EVENING. MID LEVEL FLOW IS PROGGED TO BACK AHEAD OF THE APPROACHING SOUTHERN PLAINS SHORTWAVE WHICH WILL DO LIMIT THE EASTWARD PROGRESS CONVECTION CAN MAKE...AND ALSO LEAD TO MUCH WEAKER DEEP LAYER VERTICAL WIND SHEAR GIVEN THE NEARLY UNIDIRECTIONAL FLOW. OBVIOUSLY THERE ARE A LOT OF UNCERTAINTIES REGARDING CONVECTIVE MODE AND EVOLUTION LATER TODAY AND INTO THE EVENING. SYNOPTIC SCALE FEATURES APPEAR AS THOUGH THEY COULD BECOME FAVORABLE FOR A SIGNIFICANT RAIN EVENT THIS EVENING...MAINLY TO THE WEST AND NORTHWEST OF OUR AREA...BUT POSSIBLY AS FAR EAST AS FAR WESTERN MISSOURI. STRONG SOUTHERLY LOW LEVEL JET DEVELOPING THIS EVENING WILL FORM BENEATH A BACKED SOUTHERLY MIDLEVEL FLOW...RESULTING IN NET MCS MOTION OF LESS THAN 10KT. WITH PRECIPITABLE WATERS OF OVER AN INCH AND A HALF THE POTENTIAL EXIST FOR LOCALLY VERY HEAVY RAINFALL. AGAIN A LOT WILL DEPEND ON THE ORIENTATION OF THE CONVECTION...IF THE CONVECTION ORGANIZES IN NORTHWARD MOVING BOWS THEN WIND DAMAGE BECOMES THE MAIN CONCERN. IF CONVECTION LAYS OUT PARALLEL TO THE FLOW THEN TRAINING AND EXCESSIVE/POTENTIALLY FLOODING RAINFALL BECOMES THE MAIN CONCERN. VERY LOW CONFIDENCE IN FORECAST CONVECTIVE SCALE FEATURE 12 HOURS OUT...SO WILL NEED TO BE WATCHED CLOSELY. REGARDLESS OF THE CONVECTIVE ORIENTATION THE UNIDIRECTIONAL SOUTH-SOUTHWESTERLY FLOW TONIGHT SHOULD GREATLY LIMIT THE AMOUNT OF EASTWARD PROGRESSION SO HAVE CUT BACK ON POPS OVER OUR EASTERN COUNTIES. NEXT SYNOPTIC SCALE SHORTWAVE IS FORECAST TO ROTATE OUT INTO THE CENTRAL PLAINS SATURDAY AFTERNOON...WITH A NEW ROUND OF SEVERE CONVECTION LIKELY OVER EASTERN KANSAS INTO NORTHWEST MISSOURI. THAT CONVECTION WILL THEN TRY TO MOVE EASTWARD INTO OUR WESTERN CWA...BUT GIVEN THE MID LEVEL FLOW IT IS QUESTIONABLE HOW FAR EAST CONVECTION WILL MAKE IT SATURDAY NIGHT. SEVERE POTENTIAL CERTAINLY EXIST IN OUR NW CWA SATURDAY EVENING. SUITE OF NUMERICAL MODELS INCLUDING THE WRF (WHICH HAS DONE QUITE WELL LATELY) SUGGEST THAT LOW AMPLITUDE SHORTWAVE RIDGING WILL DEVELOP OVER THE CENTRAL PLAINS SUNDAY...LEAVING OUR ONLY HOPES OF CONVECTIVE INITIATION PEGGED TO A WEAKENING SURFACE BOUNDARY LAID OUT ACROSS THE AREA. NAM FORECAST SOUNDINGS REALLY DON'T SHOW ANY EVIDENCE OF A SIGNIFICANT CAP...HOWEVER THAT IS LIKELY DUE IN LARGE PART TO THE BMJ CONVECTIVE PARAMETERIZATION OVERTURNING THINGS TOO MUCH. GIVEN RISING MID LEVEL HEIGHTS SUSPECT THAT THERE WILL BE MORE OF A CAP IN PLACE THAN THE NAM INDICATES...WHICH GIVEN ONLY WEAK TO MODEST LOW LEVEL CONVERGENCE ALONG A WEAKENING SURFACE BOUNDARY AND NO APPARENT UPPER LEVEL SUPPORT I HAVE CUT BACK ON POPS SUNDAY. OUR HOPES OF A DROUGHT BUSTING RAINS THIS WEEKEND APPEAR TO BE THINNING. DIDN'T MAKE ANY CHANGES BEYOND SUNDAY...BUT AGAIN IT APPEARS THOUGH WE WILL SEE MORE RIDGING WITH THE EDGE OF THE WESTERLIES WELL TO OUR NW...SO CONVECTIVE CHANCES LOOK PRETTY LOW IN THE EXTENDED. IZZI && .AVIATION... MAIN AVIATION CONCERN WILL DEAL WITH THE EVOLUTION OF A CONVECTIVE COMPLEX CURRENTLY AFFECTING PORTIONS OF NEBRASKA AND NORTHERN KANSAS. CORFIDI VECTORS...850-300MB THICKNESS...AND THE ORIENTATION OF INSTABILITY ALL POINT TO A SOUTHEAST TURN OF SYSTEM MOVEMENT DURING THE OVERNIGHT HOURS. AT THIS TIME...ONLY ADDED VCTS TO THE KJLN TERMINAL AS THE REMNANTS OF THIS SYSTEM MAY GRAZE FAR WESTERN MISSOURI DURING THE MID-MORNING HOURS. REDEVELOPMENT OF CONVECTION IS POSSIBLE ACROSS THE FORECAST AREA DURING THE AFTERNOON. HOWEVER...UNCERTAINTY IS HIGH AS CLOUD COVER MAY GREATLY REDUCE INSTABILITY. FOR NOW...WILL JUST HAVE VFR CEILINGS DURING THE DAY AND INTO THE EVENING. SAW && .SGF WATCHES/WARNINGS/ADVISORIES... .MO...NONE. .KS...NONE. $$ WFO SGF mo AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO 330 AM CDT FRI JUN 3 2005 .DISCUSSION... MESSY...MESSY...MESSY. THAT IS WHAT THE NEXT 3 DAYS WILL BRING AS SEVERAL UPPER LEVEL DISTURBANCES/MCS FEATURES WILL MAKE IT A JOY TO HIT TEMPERATURE FORECASTS AND BREAK DOWN ARRIVAL OF CONVECTION. LARGE SCALE PATTERN IS DENOTED BY LARGE UPPER TROUGH OVER THE NORTHERN ROCKIES WITH SHORTWAVE OVER NV ROTATING UNDERNEATH...THIS FEATURE WILL BEAR WATCHING FOR SEVERE POTENTIAL ON SATURDAY AFTERNOON AND EVENING. SHARP SHORTWAVE TROUGH CROSSING NORTHERN MEXICO WILL ALSO BE A PLAYER FOR CONVECTION TONIGHT. IN THE SHORT TERM MCS MOVING INTO EASTERN NEBRASKA AND TRAILING BACK INTO CENTRAL KS HAS FINALLY STARTED TO TURN MORE SOUTHEAST ON THE SOUTHERN END. HOWEVER...MID LEVEL CAP HAS THWARTED DEVELOPMENT OF CONVECTION ANY FURTHER SOUTHWEST. STILL EXPECT THE SOUTHERN PORTION OF MCS TO MOVE INTO NORTHWEST AND PORTIONS OF WEST CENTRAL MO SHORTLY AFTER 12Z. SINCE MCS WILL BE MOVING INTO A LESS FAVORABLE ENVIRONMENT...I.E. MORE STABLE/LESS MOISTURE...EXPECT CONVECTION TO WEAKEN AS IT MOVES INTO FAR WESTERN CWA THIS MORNING AS NOTED BY 00Z GFS AND LATEST RUC QPF. HAVE DOUBTS AS TO WHETHER OR NOT THERE WILL BE REDEVELOPMENT OF CONVECTION THIS AFTERNOON TIED TO REMNANTS OF MCS AS EXTENSIVE CLOUD DEBRIS WILL LIMIT AFTERNOON HEATING. HAVE LOWERED HIGH TEMPERATURES BY A CATEGORY OVER WESTERN CWA FOR TODAY. SEVERE POTENTIAL ALSO LIMITED DUE TO THE EXPECTED WIDESPREAD CLOUD COVER AND MARGINAL INSTABILITY. HAVE BUMPED POPS UP FOR TONIGHT TO LIKELY CATEGORY OVER ALL BUT FAR EASTERN CWA AS SHORTWAVE OVER NORTHERN MEXICO LIFTS NORTHEAST. 850MB LOW LEVEL JET EXPECTED TO VEER THIS EVENING AND DRAW DEEPER MOISTURE NORTHWARD AND AHEAD OF THIS SHORTWAVE. PRECIPITABLE WATER VALUES WILL BE ON THE INCREASE TONIGHT AND COULD HAVE A HYDRO PROBLEM OVER FAR WESTERN CWA WHERE FFG VALUES ARE AROUND 1.5 INCHES/1 HOUR. HAVE KEPT LOW CHANCE POPS IN FOR SATURDAY AS MESOSCALE BOUNDARIES LEFT OVER FROM TONIGHTS CONVECTION COULD PLAY A ROLE IN SCATTERED CONVECTION. HOWEVER...BETTER BET FOR CONVECTION STARTS LATE SATURDAY AFTERNOON OR BETTER YET SATURDAY EVENING AS SHORTWAVE NOW ROLLING THROUGH NV IS PROGGED TO SHARPEN AS IT LIFTS NORTHEAST THROUGH KS. A STALLED COLD FRONT IS FORECAST TO BE NEAR NORTHWEST MO BY SATURDAY AFTERNOON WITH A SOUTHERLY LOW LEVEL JET REFORMING OVER EASTERN KS. BY THIS TIME THE LOW LEVEL JET WILL HAVE BEEN ABLE TO TRANSPORT UPPER 60 DEWPOINTS INTO THE REGION. NAM APPEARS TO BE OVER FORECASTING THE LOW LEVEL DEWPOINTS...AND THUS INSTABILITY. NONETHELESS EXPECT TO SEE MUCAPES WELL IN EXCESS OF 3000 J/KG ON SATURDAY WITH SUFFICIENT 0-6KM SHEAR TO SUPPORT SEVERE CONVECTION. HAVE MADE MINOR CHANGES TO REST OF FORECAST WITH THE MOST NOTABLE LOWERING RAIN CHANCES ON MONDAY TO SLIGHT CATEGORY. MJ && .PREV DISCUSSION... 809 PM... MINOR REVISION TO SLOW DOWN THUNDERSTORM ARRIVAL A BIT IN THE NORTHWEST PART OF FORECAST AREA TONIGHT. ONGOING STORMS STILL WELL WEST OF REGION...AND UPPER AIR THIS EVENING SHOWING QUITE A BIT OF DRY AIR LEFT OVER IN EASTERN KANSAS IN WAKE OF CONVECTION THAT MOVED THROUGH THIS AFTERNOON...SO EXPECT ANY RETURN FLOW SET UP NOT TO OCCUR UNTIL LATE TONIGHT. THUS WILL TAKE OUT ANY MENTION OF EVENING POPS. PC && .PREV DISCUSSION... 255 PM... MID/UPPER LEVEL CYCLONE CONTINUES TO ROTATE OVER SOUTHERN SASKATCHEWAN THIS AFTERNOON. THIS FEATURE WILL GRADUALLY LIFT NORTH...ALLOWING SEVERAL SHORTWAVES TO MOVE ACROSS THE CENTRAL PLAINS OVER THE WEEKEND. IN THE MEANTIME...THUNDERSTORMS THAT DEVELOP OVER WESTERN/CENTRAL KANSAS THIS AFTERNOON/EVENING ARE EXPECTED TO ORGANIZE INTO A CONVECTIVE COMPLEX TONIGHT AS THEY ENCOUNTER A 40-50 KNOT LOW LEVEL JET AND WARM AIR ADVECTION PROCESSES ENSUE. FORWARD PROPAGATING CORFIDI VECTORS INDICATE EASTWARD MOVEMENT OF THIS CONVECTIVE SYSTEM...ALTHOUGH EXPECT THE BULK OF THE ACTIVITY TO REMAIN WEST OF THE FORECAST AREA UNTIL CLOSER TO DAYBREAK. LOW LEVEL WINDS WILL VEER TO THE SOUTH EARLY FRIDAY...AND ALLOW LOW LEVEL MOISTURE TO SPREAD INTO THE FORECAST AREA. ALTHOUGH PROGGED DEW POINTS ON FRIDAY AFTERNOON MAY BE OVERDONE (LOW 70S BY GFS AND NAM SOLUTIONS)...STILL SHOULD HAVE AMPLE MOISTURE FOR THUNDERSTORM DEVELOPMENT. THE HIGHEST THREAT FOR STRONG TO SEVERE ACTIVITY APPEARS TO BE ACROSS EASTERN KANSAS AND WESTERN MISSOURI CLOSER TO THE WARM FRONT...WHERE FORECAST MUCAPES ARE AROUND 2500 J/KG AND MID LEVEL LAPSE RATES ARE CONDITIONALLY UNSTABLE. ANTICIPATE CONVECTION TO SPREAD ACROSS THE FORECAST AREA ON FRIDAY NIGHT AS A SHORTWAVE IMPULSE...AGREED UPON BY BOTH NAM AND GFS SOLUTIONS...OFFERS ADDITIONAL SUPPORT. HAVE PLACED THE HIGHEST POPS (60 PERCENT) ACROSS THE WESTERN HALF OF THE CWA BETWEEN 06Z-12Z SATURDAY. ADDITIONAL THUNDERSTORM DEVELOPMENT APPEARS POSSIBLE ON SATURDAY...ESPECIALLY ACROSS NORTHERN MISSOURI...AS A SURFACE FRONT PASSES. ADDITIONAL SEVERE THUNDERSTORM ACTIVITY APPEARS POSSIBLE. SUBTLE FLUCTUATIONS IN THE POSITION OF THE TROUGH OVER THE NORTHERN ROCKIES NEXT WEEK WILL MAKE A BIG DIFFERENCE IN PRECIPITATION CHANCES OVER EASTERN KANSAS AND WESTERN MISSOURI. THUNDERSTORM CHANCES LOOK TO BE THE BEST SUNDAY AND MONDAY. A STALLED SURFACE FRONT EXTENDING ACROSS KANSAS AND MISSOURI WILL BE THE FOCUS FOR THUNDERSTORM CLUSTERS. THE ECMWF AND GFS BUILD HEIGHTS OVER PLAINS TUESDAY AND WEDNESDAY, AND THE FOCUS FOR STORMS WILL LIKELY MOVE INTO THE NORTHERN HIGH PLAINS. WITH HIGHER HEIGHTS OVER KANSAS TUESDAY AND WEDNESDAY CAP STRENGTH WILL INCREASE OVER KANSAS. 700 MB TEMPERATURES ARE FORECAST TO BE COOLER OVER CENTRAL AND EASTERN MISSOURI TUESDAY AND WEDNESDAY, SO LATE AFTERNOON AND EARLY EVENING POP UP STORMS CAN'T BE RULED OUT. I'VE KEPT 20 PERCENT CHANCES IN FOR THE KIRKSVILLE, CONCORDIA AND SEDALIA AREAS. SCHMIT/KOCH 655 AM CDT THU... QUICK ADJUSTMENT TO THE MORNING FORECAST TO REMOVE MENTION OF AREAS OF FOG. LIGHT EAST WINDS ADVECTED IN DRY AIR ALL NIGHT. SO...ANYTHING OTHER THAN SHALLOW SURFACE BASED FOG NEAR LARGE BODIES OF WATER...OR IN LOW LYING AREAS...IS HARD TO COME BY. FOR THOSE IN THE AVIATION COMMUNITY...AIRPORTS NEAR THE MISSOURI RIVER (MKC AND STJ) MAY STILL EXPERIENCE REDUCED VISIBILITIES THROUGH 9 AM. CUTTER && .EAX WATCHES/WARNINGS/ADVISORIES... MO...NONE. KS...NONE. $$ mo AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE AMARILLO TX 414 AM CDT FRI JUN 3 2005 .DISCUSSION... WOW...WHAT A SCENARIO WE HAVE TODAY! SURFACE ANALYSIS INDICATED A COLD FRONT EDGING INTO THE WESTERN OKLAHOMA AND NORTHWEST TEXAS PANHANDLES WHILE THE DRY LINE HUGGED NEAR THE NEW MEXICO/TEXAS STATE LINE. THIS BOUNDARY WILL COME A HALT WHILE AN UPPER LEVEL SYSTEM...LOCATED OVER NEW MEXICO TRACKS NORTHEAST ACROSS THE PANHANDLES THIS MORNING. INCREASED THE POPS THIS MORNING...PARTICULARLY OVER THE WESTERN AREAS...GIVEN FORCING AVAILABLE WITH THIS SYSTEM. THE MAIN SHORTWAVE AXIS IS LAGGING BEHIND THIS LEADING IMPULSE ACCORDING TO THE WATER VAPOR IMAGERY AND RUC ANALYSIS. WE EXPECT THIS FEATURE TO MOVE INTO THE AREA BY PEAK HEATING. CONCERNED THAT MORNING CONVECTION AND CLOUD COVER MAY BECOME A HINDERANCE FOR AFTERNOON DEVELOPMENT OVER THE EASTERN HALF OF THE PANHANDLES WHERE CONDITIONAL INSTABILITY WILL BE HIGHEST. THOUGH SEVERE WORDING WAS ADDED FOR THIS AFTERNOON AND EVENING...CONFIDENCE IS LOW. ANOTHER LOW PRESSURE SYSTEM LOCATED OVER THE GREAT BASIN EARLY THIS MORNING...WILL FOLLOW AFTERWARDS AND WILL DRIVE THE AFOREMENTIONED FRONT SOUTHWARD. BOTH THE NAM AND GFS AGREE THAT THE FRONT WILL ADVANCE FURTHER SOUTH THAT PREVIOUSLY THOUGHT. ADJUSTED THE WIND AND DEWPOINT GRIDS SIGNIFICANTLY TO MATCH LATEST TREND. POPS WHERE ADJUSTED SLIGHTLY ALSO. RIDGE BUILDS OVERHEAD ON SUNDAY AND MONDAY. EXPECT WARMER AND DRIER CONDITIONS BEFORE MOISTURE RETURNS WITH THE NEXT SCHEDULED SYSTEM ON TUESDAY. && .PRELIMINARY POINT TEMPS/POPS... AMARILLO TX 81 58 84 60 / 40 30 0 10 BEAVER OK 79 63 88 60 / 50 40 20 20 BOISE CITY OK 78 55 77 55 / 30 20 10 20 BORGER TX 82 60 87 63 / 40 30 10 10 BOYS RANCH TX 83 57 85 58 / 50 20 0 10 CANYON TX 84 57 85 59 / 40 30 0 10 CLARENDON TX 83 62 89 63 / 50 40 10 10 DALHART TX 79 56 79 56 / 40 20 10 10 GUYMON OK 80 61 81 58 / 30 30 10 20 HEREFORD TX 86 57 83 59 / 40 10 0 10 LIPSCOMB TX 80 64 89 62 / 50 40 10 20 PAMPA TX 81 62 87 64 / 50 40 10 20 SHAMROCK TX 82 65 92 65 / 50 40 10 20 WELLINGTON TX 83 66 94 66 / 50 40 10 20 && .AMA WATCHES/WARNINGS/ADVISORIES... OK...NONE. TX...NONE. && $$ 13/08 tx AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SAN ANGELO TX 315 AM CDT FRI JUN 3 2005 .SHORT TERM... STRONG SHORTWAVE PUSHING UP THROUGH BIG BEND THIS MORNING WITH STRONG LIFT AHEAD OF IT. RUC MUCAPES 3500-4000 J/KG AND DEW POINTS IN UPPER 60S...SO LOTS OF INSTABILITY. MOST OF CONVECTION JUST WEST OF CWA...FROM ALPINE AND FORT STOCKTON...NORTHWARD TO MIDLAND AND LUBBOCK...TRAINING NORTHEAST. WEAKER AND MORE SCATTERED SHOWERS AND THUNDERTORMS WERE ALSO OCCURRING JUST SOUTH OF CWA. THIS IS SOMEWHAT SURPRISING IN SOME RESPECTS...GIVEN THE STRONG INSTABILITY WITH SHORTWAVE. BOTH GFS AND NAM MODELS JUST GRAZE WESTERN CWA CURRENTLY OVER THE PERMIAN BASIN TO LUBBOCK...WITH PERMIAN BASIN MCS. THEY ALSO HINT AT MCS DEVELOPMENT WITH THE SECONDARY SCATTERED SHOWERS AND THUNDERSTORMS TO OUR SOUTH...WITH THE GFS MOST AGGRESSIVE INDICATING UP TO 1 1/2 INCHES NEAR SONORA BY 7 AM THIS MORNING. THIS HAS NOT HAPPENED YET...BUT STILL HAVE THE MONITOR POTENTIAL AS BOTH MODELS BRING STRONG 700 HT UVVS ACROSS CWA DURING THE MORNING HOURS. WITH STRONG INSTABILILTY...WILL MENTION SEVERE AND HEAVY RAINFALL IN ZONES FOR THIS MORNING. WILL LIKELY SEE SEVERE THUNDERSTORM WATCHES FOR HAIL AND DAMAGING WINDS. THERE IS TRAINING POTENTIAL...AS CURRENT STORMS IN PERMIAN BASIN ATTEST. HEAVIEST EARLY MORNING RAINFALL APPEARS TO GRAZE CROCKETT...IRION...STERLING...NOLAN...FISHER AND HASKELL COUNTIES. LIFT FROM SHORTWAVE EXITS CWA BY NOON. KEPT A MENTION OF A SLIGHT CHANCE/CHANCE OF AFTERNOON STORMS IN BIG COUNTRY AND HEARTLAND COUNTIES...HOWEVER...WITH OLD THUNDERSTORM OUTFLOW BOUNDARIES. LEFT OUT RAIN MENTION IN AFTERNOON FOR CONCHO VALLEY AND AREAS SOUTHWARD. .LONG TERM... MOISTURE AND INSTABILITY WILL REMAIN OVER CWA. MENTIONED A SLIGHT CHANCE/CHANCE OF STORMS SATURDAY/SATURDAY NIGHT AS A WEAK SHORTWAVE MOVES ACROSS...THEN AGAIN ON MONDAY AFTERNOON/EVENING FOR ANOTHER SHORTWAVE. CAN'T RULE OUT ISOLATED STORMS ALL NEXT WEEK...WITH WEAKLY DIVERGENT PATTERN IN SOUTHWEST FLOW LOFT. LONG WAVE TROUGH MOVES INTO THE WEST LATE NEXT WEEK...BRINGING ANOTHER CHANCE OF STORMS. && .PRELIMINARY POINT TEMPS/POPS... ABILENE 84 68 94 68 / 70 20 20 30 SAN ANGELO 87 69 94 69 / 60 10 20 40 JUNCTION 87 68 90 68 / 50 20 20 40 && .SJT WATCHES/WARNINGS/ADVISORIES... TX...TORNADO WATCH FOR CROCKETT...SCHLEICHER...SUTTON...IRION...AND STERLING COUNTIES UNTIL 4 AM. && $$ 04 tx AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SPRINGFIELD MO 624 AM CDT FRI JUN 3 2005 .UPDATE... CALLS TO SOUTH CENTRAL MISSOURI INDICATE THAT DENSE FOG HAS BECOME WIDESPREAD ENOUGH TO REQUIRE AN NPW. HAVE ISSUED THE FOG ADV UNTIL 9 AM...UPDATED GRIDS AND DERIVED PRODUCTS HAVE BEEN SENT. SAW && .AVIATION... FOR THE 12Z TAFS...SOME LIGHT FOG OR HAZE EARLY THIS MORNING WILL BURN OFF QUICKLY BY MID MORNING. MCS TO THE NORTH IS LOOKING MORE AND MORE LIKE IT WILL REMAIN NORTH OF BOTH TERMINALS TODAY. CHANCES OF SHOWERS AND THUNDERSTORMS WILL INCREASE LATER THIS AFTERNOON INTO TONIGHT...MAINLY WEST TOWARD JLN. TIMING OF SHOWERS AND THUNDERSTORMS IS NEARLY IMPOSSIBLE AT THIS POINT...SO WILL LET LATER SHIFTS INTRODUCE PRECIPITATION ONCE TIMING BECOMES CLEARER. IZZI && .DISCUSSION... APOLOGIZE FOR THE LATE AND LONG AFD...BUT LOTS TO EXAMINE AND TALK ABOUT THIS MORNING... TIS THE SEASON OF MCS'S. LARGE MCS OVER NEBRASKA CONTINUES TO MARCH EASTWARD WITH THE TAIL END OF THE MCS BEGINNING TO LAY OUT ACROSS NORTH CENTRAL KANSAS. THE PROGRESSIVE NORTHERN PORTION OF THE MCS IS ABOUT TO RUN OUT OF INSTABILITY AND WILL LIKELY WEAKEN RAPIDLY AS IT MOVES INTO WESTERN IOWA AND NORTHWEST MISSOURI. SPC MESOANALYSIS PAGE SHOWS THAT THE EASTERN EXTENT OF THE INSTABILITY EXTENDS ABOUT AS FAR EASTWARD AS THE KANSAS MISSOURI BORDER...AND EVEN THERE MUCAPES ARE <750 J/KG. CORFIDI VECTORS FROM THE RUC AND NAM BOTH INDICATE THAT A TURN TO ALMOST DUE SOUTH WILL OCCUR WITH TAIL END OF THE MCS THIS MORNING...AND THIS WOULD SEEM TO MAKE SENSE GIVEN THE NORTH TO SOUTH ORIENTED INSTABILITY AXIS. GIVEN THE SHARP N/S INSTABILITY AXIS DECIDED TO KEEP A SHARP EAST/WEST POP GRADIENT ACROSS THE CWA TODAY WITH RAIN VERY UNLIKELY OVER THE FAR EASTERN OZARKS TODAY AS THIS MCS RAPIDLY WEAKENS AS IT MOVES EASTWARD. NOW THIS MCS IS OUR MOST IMMEDIATE CONCERN...BUT IT IS FAR FROM THE ONLY CONCERN. VIGOROUS SHORTWAVE IS LIFTING NORTHEAST ACROSS THE RIO GRAND VALLEY AREA OF SOUTHWEST TEXAS. CONVECTION ASSOCIATED WITH THAT SHORTWAVE IS CURRENTLY MORPHING INTO ANOTHER MCS. IT APPEARS AS THOUGH THE BRUNT OF THIS MCS WILL MOVE MORE EAST THAN NORTHEAST...WHICH IS SUPPORTED BY CORFIDI VECTORS AND 850-300MB THICKNESS. THE SYNOPTIC SCALE SHORTWAVE RESPONSIBLE FOR THIS CONVECTION MOVE NORTHEAST INTO OKLAHOMA THIS AFTERNOON...HOWEVER THE SURFACE BOUNDARY WILL PROBABLY REMAIN FURTHER WEST ACROSS THE PANHANDLE REGION NORTHWARD INTO CENTRAL KANSAS. WITH UPPER SUPPORT REALLY NOT JUXTAPOSED WITH SURFACE BOUNDARY THIS AFTERNOON IT IS DIFFICULT TO PINPOINT OR EVEN MAKE A GOOD GUESS AT CONVECTIVE INITIATION...ESPECIALLY GIVEN THE SOUTHWARD MOVING MCS OVER KANSAS. GIVEN THE LARGE SCALE SUPPORT FOR CONVECTION IT SEEMS LIKELY THAT THE CURRENT MCS OVER NORTHERN KANSAS WILL EITHER SURVIVE INTO THE AFTERNOON AND RE-INTENSIFY...OR LEAVE BEHIND AN OUTFLOW BOUNDARY THAT WILL BE THE FOCUS FOR A NEW BATCH OF CONVECTION OVER OK/KS THIS AFTERNOON AS LARGE SCALE ASCENT INCREASES AHEAD OF THE APPROACHING SHORTWAVE. STILL APPEARS AS THOUGH THE AXIS OF MAXIMUM INSTABILITY WILL REMAIN WEST OF OUR CWA...PROBABLY INCHING INTO OUR WESTERN COUNTIES THIS AFTERNOON AS EASTERLY LOW LEVEL FLOW CONTINUES TO RETARD NORTHWARD ADVECTION OF MOISTURE. BEST GUESS NOW IS THAT STRONG/POTENTIALLY SEVERE CONVECTION WILL FORM OVER OK/KS THIS AFTERNOON AND EVENING. MID LEVEL FLOW IS PROGGED TO BACK AHEAD OF THE APPROACHING SOUTHERN PLAINS SHORTWAVE WHICH WILL DO LIMIT THE EASTWARD PROGRESS CONVECTION CAN MAKE...AND ALSO LEAD TO MUCH WEAKER DEEP LAYER VERTICAL WIND SHEAR GIVEN THE NEARLY UNIDIRECTIONAL FLOW. OBVIOUSLY THERE ARE A LOT OF UNCERTAINTIES REGARDING CONVECTIVE MODE AND EVOLUTION LATER TODAY AND INTO THE EVENING. SYNOPTIC SCALE FEATURES APPEAR AS THOUGH THEY COULD BECOME FAVORABLE FOR A SIGNIFICANT RAIN EVENT THIS EVENING...MAINLY TO THE WEST AND NORTHWEST OF OUR AREA...BUT POSSIBLY AS FAR EAST AS FAR WESTERN MISSOURI. STRONG SOUTHERLY LOW LEVEL JET DEVELOPING THIS EVENING WILL FORM BENEATH A BACKED SOUTHERLY MIDLEVEL FLOW...RESULTING IN NET MCS MOTION OF LESS THAN 10KT. WITH PRECIPITABLE WATERS OF OVER AN INCH AND A HALF THE POTENTIAL EXIST FOR LOCALLY VERY HEAVY RAINFALL. AGAIN A LOT WILL DEPEND ON THE ORIENTATION OF THE CONVECTION...IF THE CONVECTION ORGANIZES IN NORTHWARD MOVING BOWS THEN WIND DAMAGE BECOMES THE MAIN CONCERN. IF CONVECTION LAYS OUT PARALLEL TO THE FLOW THEN TRAINING AND EXCESSIVE/POTENTIALLY FLOODING RAINFALL BECOMES THE MAIN CONCERN. VERY LOW CONFIDENCE IN FORECAST CONVECTIVE SCALE FEATURE 12 HOURS OUT...SO WILL NEED TO BE WATCHED CLOSELY. REGARDLESS OF THE CONVECTIVE ORIENTATION THE UNIDIRECTIONAL SOUTH-SOUTHWESTERLY FLOW TONIGHT SHOULD GREATLY LIMIT THE AMOUNT OF EASTWARD PROGRESSION SO HAVE CUT BACK ON POPS OVER OUR EASTERN COUNTIES. NEXT SYNOPTIC SCALE SHORTWAVE IS FORECAST TO ROTATE OUT INTO THE CENTRAL PLAINS SATURDAY AFTERNOON...WITH A NEW ROUND OF SEVERE CONVECTION LIKELY OVER EASTERN KANSAS INTO NORTHWEST MISSOURI. THAT CONVECTION WILL THEN TRY TO MOVE EASTWARD INTO OUR WESTERN CWA...BUT GIVEN THE MID LEVEL FLOW IT IS QUESTIONABLE HOW FAR EAST CONVECTION WILL MAKE IT SATURDAY NIGHT. SEVERE POTENTIAL CERTAINLY EXIST IN OUR NW CWA SATURDAY EVENING. SUITE OF NUMERICAL MODELS INCLUDING THE WRF (WHICH HAS DONE QUITE WELL LATELY) SUGGEST THAT LOW AMPLITUDE SHORTWAVE RIDGING WILL DEVELOP OVER THE CENTRAL PLAINS SUNDAY...LEAVING OUR ONLY HOPES OF CONVECTIVE INITIATION PEGGED TO A WEAKENING SURFACE BOUNDARY LAID OUT ACROSS THE AREA. NAM FORECAST SOUNDINGS REALLY DON'T SHOW ANY EVIDENCE OF A SIGNIFICANT CAP...HOWEVER THAT IS LIKELY DUE IN LARGE PART TO THE BMJ CONVECTIVE PARAMETERIZATION OVERTURNING THINGS TOO MUCH. GIVEN RISING MID LEVEL HEIGHTS SUSPECT THAT THERE WILL BE MORE OF A CAP IN PLACE THAN THE NAM INDICATES...WHICH GIVEN ONLY WEAK TO MODEST LOW LEVEL CONVERGENCE ALONG A WEAKENING SURFACE BOUNDARY AND NO APPARENT UPPER LEVEL SUPPORT I HAVE CUT BACK ON POPS SUNDAY. OUR HOPES OF A DROUGHT BUSTING RAINS THIS WEEKEND APPEAR TO BE THINNING. DIDN'T MAKE ANY CHANGES BEYOND SUNDAY...BUT AGAIN IT APPEARS THOUGH WE WILL SEE MORE RIDGING WITH THE EDGE OF THE WESTERLIES WELL TO OUR NW...SO CONVECTIVE CHANCES LOOK PRETTY LOW IN THE EXTENDED. IZZI && .AVIATION... MAIN AVIATION CONCERN WILL DEAL WITH THE EVOLUTION OF A CONVECTIVE COMPLEX CURRENTLY AFFECTING PORTIONS OF NEBRASKA AND NORTHERN KANSAS. CORFIDI VECTORS...850-300MB THICKNESS...AND THE ORIENTATION OF INSTABILITY ALL POINT TO A SOUTHEAST TURN OF SYSTEM MOVEMENT DURING THE OVERNIGHT HOURS. AT THIS TIME...ONLY ADDED VCTS TO THE KJLN TERMINAL AS THE REMNANTS OF THIS SYSTEM MAY GRAZE FAR WESTERN MISSOURI DURING THE MID-MORNING HOURS. REDEVELOPMENT OF CONVECTION IS POSSIBLE ACROSS THE FORECAST AREA DURING THE AFTERNOON. HOWEVER...UNCERTAINTY IS HIGH AS CLOUD COVER MAY GREATLY REDUCE INSTABILITY. FOR NOW...WILL JUST HAVE VFR CEILINGS DURING THE DAY AND INTO THE EVENING. SAW && .SGF WATCHES/WARNINGS/ADVISORIES... .MO...NONE. .KS...NONE. $$ WFO SGF mo AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NEWPORT/MOREHEAD CITY NC 922 AM EDT FRI JUN 3 2005 .SHORT TERM (TODAY)...VERY MOIST AIRMASS IN PLACE WITH THE 12Z SOUNDING SHOWING PRECIP WATER CLOSE TO 2 INCHES. INSTABILITY ALSO PRESENT WITH UNMODIFIED LI NEAR MINUS 5 AND CAPE AROUND 1800 J/KG. REGIONAL RADAR LOOPS CURRENTLY INDICATING A LULL IN THE ACTIVITY OVER OUR CWA WITH GFS/ETA AND RUC ALL INDICATING WEAK SUBSIDENCE. WILL CONSEQUENTLY LOWER POPS A BIT FROM CATEGORICAL STATUS ESP INLAND...WHILE INDICATING CONTINUED HI POPS ALONG THE OUTER BANKS. FCST MAX TEMPS STILL LOOK FINE AND NO OTHER CHGS TO CURRENT FCST PLANNED. && .AVIATION...WIDESPREAD IFR CONDITIONS IN FOG/STRATUS WILL LIFT THIS MORNING. CONVECTIVE ACTIVITY WILL BECOME SCT IN THE AFTERNOON WITH SHOWER OR STORM PRODUCING IFR CONDS. && .MARINE...WINDS ACROSS THE CWF AREA ARE MOSTLY SE AOB 15 KT. CURRENT FORECAST IS ON TRACK. WILL MAKE MINOR CHANGES AND REMOVE MORNING WORDING. SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE...MAINLY N OF CAPE LOOKOUT. .RIP CURRENTS... RESIDUAL EASTERLY SWELL COMBINED WITH WEAK ONSHORE FLOW WILL PRODUCE A HIGH THREAT OF DANGEROUS RIP CURRENTS NORTH OF HSE AND A MODERATE THREAT FOR THE WATERS SOUTH OF HATTERAS THROUGH THIS AFTERNOON. && .MHX WATCHES/WARNINGS/ADVISORIES... NC...NONE. MARINE...SMALL CRAFT ADVISORY FOR AMZ152-154-156 UNTIL 11 PM FRIDAY. ...SMALL CRAFT ADVISORY FOR AMZ150 UNTIL 1 AM SATURDAY. && $$ SHORT TERM...COLLINS AVIATION...PRINGLE MARINE...PRINGLE nc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND 1001 AM CDT FRI JUN 3 2005 .DISCUSSION...MAIN CHALLENGE FOR TODAY IS SHOWER/THUNDER CHANCES. COMPLEX SITUATION WITH MANY PARAMETERS TO TALK ABOUT...WILL ONLY MENTION MOST IMPORTANT. THETA-E RIDGE EXTENDS THROUGH RED RIVER VALLEY WITH 700MB FLOW UP VALLEY. ISENTROPIC LIFT/700MB FRONTOGENESIS LOOKS TO PLAY A ROLE THROUGH THE DAY AS THETA-E RIDGE WILL HAVE A HARD TIME PROPAGATING EAST. WITH FORCING AND WEAK INSTABILITY IN PLACE WILL INCREASE POPS ALONG VALLEY. QPF UP TO AN INCH WILL BE POSSIBLE TODAY. SEVERE POTENTIAL WOULD BE ALONG FAR WESTERN FORECAST AREA (FA) IF CLOUDS CLEAR. THIS WOULD GIVE MLCAPES 1000-1200 J/KG. MAIN QUESTIONS WILL BE POSITION OF SFC BOUNDARY AND AMOUNT OF HEATING. CURRENTLY MAIN THREAT APPEARS TO BE ACROSS CENTRAL NORTH DAKOTA WITH 12Z NAM/RUC INDICATING SFC BOUNDARY/BEST INSTABILITY ACROSS THIS AREA. ALL IN ALL FORECAST LOOKS ON TRACK. UPDATE FOR PRECIP WILL BE SENT BY 1030AM. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...ESF ISSUED THROUGH SATURDAY FOR HEAVY RAIN POTENTIAL. MN...ESF ISSUED THROUGH SATURDAY FOR HEAVY RAIN POTENTIAL. && $$ GRAFENAUER nd AREA FORECAST DISCUSSION...12Z AVIATION UPDATE NATIONAL WEATHER SERVICE WILMINGTON OH 639 AM EDT FRI JUN 3 2005 .AVIATION (12Z-12Z)... UPR LO SLOWLY MOVING ACRS KY THIS MRNG. HAVE SEEN AN INCREASE IN PCPN ACRS CNTRL KY IMMEDIATELY AHEAD OF UPR LO AND ASSOCD MID LVL VORT. SCT -SHRA STARTING TO WORK INTO SRN FCST AREA. IN SHORT TERM...KCVG/KLUK/KILN ALL HAVE BEST SHOT OF SEEING PCPN. HAVE INDICATED VCSH TO START...THEN BRING IN PREVAILING -SHRA FROM MID MRNG TO ERLY AFTN AS UPR LO AND MID LVL VORT PASS TO SOUTH OF FCST AREA. NRN TAF SITES WILL SEE SCT -SHRA BUT EXPECTING LESS COVERAGE IN DAY/CMH METROS. WILL COVER WITH VCSH. CIGS HAVE LOWERED INTO MVFR CAT INVOF OF UPR LO FROM NEAR KSDF SOUTHWARD INTO NRN TN. THIS SHOULD ROTATE INTO FCST AREA AHEAD OF UPR LO FOR LATER THIS MRNG. WILL SEE CIGS LIFT THIS AFTN AS UPR LO BEGINS TO WEAKEN. MAY EVEN SEE A FEW BREAKS OF SUN THIS AFTN. WITH CLOSE PROXIMITY TO UPR LO THIS AFTN AND RUC/NAM INDCG SOME WEAK INSTABILITY WITH DIURNAL HEATING...COULD SEE FEW TSRA. UNCERTAINTY REMAINS ON HOW MUCH SKIES WILL CLEAR OVERNIGHT...AS PLENTY OF LO LVL MOISTURE REMAINS. LIKELY TO SEE FOG FORMATION AS DEWPTS PROGGED TO RISE INTO L/M60S. HAVE INDICATED MVFR VSBYS LATE...WITH IFR AT KLUK. RYAN && .PREVIOUS DISCUSSION... (ISSUED 332 AM EDT FRI JUN 3 2005) SHORT TERM (TODAY THROUGH SUNDAY)... SURFACE ANALYSIS SHOWS SURFACE LOW OVER WESTERN KENTUCKY. WATER VAPOR SHOWS UPPER LOW STACKED OVER TOP THE SURFACE LOW. SATELLITE IMAGERY ALSO SHOWS PLENTY OF CLOUD COVER OVER THE REGION. REGIONAL RADARS SHOWS MUCH OF THE REGION DRY AT THE MOMENT WITH SOME CONVECTION SHOWING UP NEAR KLEX. MODELS ARE IN RELATIVELY GOOD AGREEMENT WITH SYNOPTIC PATTERN. THE SUBTLE TIMING OF MID LEVEL WAVES IS OF COURSE EVIDENT. OVERALL...CHANCE POPS WILL HANDEL EXPECTED CONDITIONS FOR TODAY INTO THIS EVENING. MARGINAL INSTABILITY TODAY ALONG WITH NOT MUCH IN THE WAY OF FORCING WITH LEAD TO ONLY SCATTERED SHOWERS. PRECIP EFFICIENCIES SHOW BEST THREAT OVER NORTHEAST KENTUCKY AND SOUTHEAST OHIO AROUND 00Z. LACK OF FORCING AND UPPER RIDGE BUILDING IN WILL CUT OFF THE THREAT OF PRECIP FOR THE REST OF TONIGHT. HAVE KEPT THE MO CLOUDY SKIES FOR TONIGHT. HOWEVER, IT MAY END UP BEING A PC. CONFIDENCE IS LOW DUE TO A LOT OF MOISTURE STILL HANGING AROUND. THUS HAVE LET CURRENT FORECAST STAND. WILL REINTRODUCE POPS SAT AFT WITH GOOD SOUTHWEST FLOW...MODERATE INSTABILITY AND A MID LEVEL WAVE MOVING ACROSS FA. THREAT WILL CONTINUE THROUGH SUNDAY NIGHT. MAV TEMPS LOOK PRETTY GOOD IN GENERAL. THE ONLY REAL DEVIATION IS FOR SATURDAY WHERE MET HIGHS LOOKED A BETTER. TIPTON LONG TERM (SUNDAY NIGHT THROUGH THURSDAY)... EXTENDED HAS REMAIN ESSENTIALLY THE SAME. HAVE REDUCED POPS MONDAY INTO TUESDAY. GFS SUGGESTS COMPLETELY DRY BUT BUT WILL NOT BITE ON IT YET AS MODELS HAVE HAD A TOUGH TIME LOCKING ONTO A SOLUTION. WILL LET DAY SHIFT LOOK AT NEW RUN AND DECIDE WHETHER POP STAYS OR GOES. FOR THOUGHTS ON THE REST OF THE EXTENDED SEE PREVIOUS DISCUSSION BELOW. TIPTON (ISSUED 350 PM EDT THU JUN 02 2005) PREVIOUS LONG TERM (SATURDAY THROUGH THURSDAY)... HAVE OPTED CLOSE TO THE GFS FOR EXTENDED PERIOD. WARM FRONT LIFTS NORTHEAST ACROSS REGION ON SATURDAY. SOME ISENTROPIC LIFT ASSOCIATED WITH THE FRONT DEVELOPS SO HAVE CHANCE POPS DURING THIS TIME. REGION REMAINS IN WARM SECTOR AND SOME INSTABILITY EXISTS BEFORE COLD FRONT PUSHES SOUTH BY LATE TUESDAY/EARLY WEDNESDAY. HIGH PRESSURE BUILDS IN FROM THE GREAT LAKES FOR END OF EXTENDED PERIOD. HAVE NOT STRAYED TO FAR FROM MAV NUMBERS FOR TEMPS. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ oh AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE SAN ANGELO TX 1005 AM CDT FRI JUN 3 2005 .UPDATE... FORECAST UPDATE HAS BEEN SENT TO REMOVE SEVERE THUNDERSTORM WATCH...AND TO READJUST POPS AND WEATHER FOR LATE THIS MORNING AND AFTERNOON. && .PREV DISCUSSION... (ISSUED 315 AM CDT FRI JUN 3 2005) SHORT TERM... STRONG SHORTWAVE PUSHING UP THROUGH BIG BEND THIS MORNING WITH STRONG LIFT AHEAD OF IT. RUC MUCAPES 3500-4000 J/KG AND DEW POINTS IN UPPER 60S...SO LOTS OF INSTABILITY. MOST OF CONVECTION JUST WEST OF CWA...FROM ALPINE AND FORT STOCKTON...NORTHWARD TO MIDLAND AND LUBBOCK...TRAINING NORTHEAST. WEAKER AND MORE SCATTERED SHOWERS AND THUNDERTORMS WERE ALSO OCCURRING JUST SOUTH OF CWA. THIS IS SOMEWHAT SURPRISING IN SOME RESPECTS...GIVEN THE STRONG INSTABILITY WITH SHORTWAVE. BOTH GFS AND NAM MODELS JUST GRAZE WESTERN CWA CURRENTLY OVER THE PERMIAN BASIN TO LUBBOCK...WITH PERMIAN BASIN MCS. THEY ALSO HINT AT MCS DEVELOPMENT WITH THE SECONDARY SCATTERED SHOWERS AND THUNDERSTORMS TO OUR SOUTH...WITH THE GFS MOST AGGRESSIVE INDICATING UP TO 1 1/2 INCHES NEAR SONORA BY 7 AM THIS MORNING. THIS HAS NOT HAPPENED YET...BUT STILL HAVE THE MONITOR POTENTIAL AS BOTH MODELS BRING STRONG 700 HT UVVS ACROSS CWA DURING THE MORNING HOURS. WITH STRONG INSTABILILTY...WILL MENTION SEVERE AND HEAVY RAINFALL IN ZONES FOR THIS MORNING. WILL LIKELY SEE SEVERE THUNDERSTORM WATCHES FOR HAIL AND DAMAGING WINDS. THERE IS TRAINING POTENTIAL...AS CURRENT STORMS IN PERMIAN BASIN ATTEST. HEAVIEST EARLY MORNING RAINFALL APPEARS TO GRAZE CROCKETT...IRION...STERLING...NOLAN...FISHER AND HASKELL COUNTIES. LIFT FROM SHORTWAVE EXITS CWA BY NOON. KEPT A MENTION OF A SLIGHT CHANCE/CHANCE OF AFTERNOON STORMS IN BIG COUNTRY AND HEARTLAND COUNTIES...HOWEVER...WITH OLD THUNDERSTORM OUTFLOW BOUNDARIES. LEFT OUT RAIN MENTION IN AFTERNOON FOR CONCHO VALLEY AND AREAS SOUTHWARD. LONG TERM... MOISTURE AND INSTABILITY WILL REMAIN OVER CWA. MENTIONED A SLIGHT CHANCE/CHANCE OF STORMS SATURDAY/SATURDAY NIGHT AS A WEAK SHORTWAVE MOVES ACROSS...THEN AGAIN ON MONDAY AFTERNOON/EVENING FOR ANOTHER SHORTWAVE. CAN'T RULE OUT ISOLATED STORMS ALL NEXT WEEK...WITH WEAKLY DIVERGENT PATTERN IN SOUTHWEST FLOW LOFT. LONG WAVE TROUGH MOVES INTO THE WEST LATE NEXT WEEK...BRINGING ANOTHER CHANCE OF STORMS. && .SJT WATCHES/WARNINGS/ADVISORIES... TX...NONE. && $$ tx AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DES MOINES IA 309 PM CDT FRI JUN 3 2005 .SHORT TERM...TDA THRU SUN NGT MAIN CONCERNS IN THIS WINDOW WL BE TSTM TRENDS AND SVR THREAT TNGT THRU SAT NGT. CURRENT SITUATION HAS POTENT SHRT WV LIFTING OUT OF BASE OF RCKYS LG WV TROF. STG KINEMATIC FORCING HAD OF THIS FEATURE REFLECTED IN QG FORCING MAX LIFTING ACRS KS/NE. THETA-E ADVCTN ALSO EXPANDING FM NE INTO MO WITH EVERYTHING LIFTING NEWD. DO NOT THINK ANY MDL HAS A GOOD HANDLE ON SITUATION SO FCST CONFIDENCE LOW...WHICH HAS BEEN THE CASE RECENTLY. NAM DOES NOT SEEM TO RECOGNIZE BLOSSOMING OF KS CONVECTION AHD OF SHRT WV...AND WHILE GFS DOES LATCH ONTO THIS...CONVECTIVE FEEDBACK OVERDVLPS FEATURES INTO NE/SD BY MRNG. RUC13 DVLPS SOME PCPN ACRS KS BY AFTN...BUT DSIPTS DRNG THE EVE WHICH ALSO SEEMS UNREASONABLE. THUS WL FOLLOW MORE OF A CONCEPTUAL RATHER THAN NUMERIC MDL THIS PACKAGE. AMS STILL RELATIVELY STABLE OVR IA ATTM SO DO NOT XPC ANYTHING TOO SGFNT TNGT...BUT LARGE SCALE FORCING SHOULD BE SUFFICIENT TO BRING PCPN INTO US SO GRDLLY INCRD POPS TO LIKELIES OVNGT FM SW-E. FEEL MCS WL MAKE IT FARTHER INTO FA TMRW. MDLS...ALBEIT SHAKEY...BOTH FOCUS LOW LVL JET INTO IA WITH INSTABILITY AXIS PUSHING EWD INTO US AS WELL. DO NOT HAVE ANY FEELING FOR TRENDS SO JUST WENT WITH BLANKET LIKELY POPS SAT. EVEN IF MCS DOES DSIPT AGN...WE COULD SEE SFC BASED THREAT INCR BY LATE AFTN AS FNT APCHS. FCST SOUNDINGS SUGGEST LTL CIN SO WL EXTEND THE LIKELIES INTO SAT NGT AS WELL. THIS MAY BE OUR PRIMARY SVR WINDOW FOR A FEW DAYS WITH ADAQUATE INSTABILITY AND SHEAR FOR SUPERCELLS. VARIOUS TORNADO PARAMETERS POINT TWRD THAT THREAT TOO...SPCLLY IF WE CAN GET SOME KIND OF LOW LVL BACKING FROM OUTFLOW BNDRYS OR WEAK WRMFNT. AGREE WITH SPC HATCHED OUTLOOK AND HAVE ADDED SVR MENTION TO 22-04Z TIME FRAME. PCPN THREAT SHOULD DCR SOMEWHAT SUN AS FNT PUSHES EWD AND LRG SCALE UVM LIFTS NEWD. HAVE TAPERRED POPS FM SLGTS W TO CHC E AND THEN DROPPED BACK TO SLGTS SUN NGT. DO NOT SEE MUCH HAPPENING AND MID SHIFT MAY WANT TO PULL ALTOGETHER IF SOME MDL CONSISTENCY OCCURS. DO NOT HAVE A GOOD FEELING FOR TEMPS EITHER DUE TO PCPN POTENTIAL SO GENERALLY FOLLOWED A GUIDANCE BLEND THRU PD. .LONG TERM...MON THRU FRI MDLS ARE ACTUALLY COMING TO A LTL BETTER CONSENSUS...AT LEAST EARLY IN THIS PD...BUT UNFORTUNATELY DETAILS WITH BNDRY PLACEMENT STILL SKETCHY. RDG BUILDS INTO MO VLY WITH WRMFNT DVLPG INVOF IA/MN BORDER OR A BIT FARTHER S. SOLUTIONS VARY FM 00Z GFS ENSEMBLES AND ECMWF FARTHER INTO IA...WHILE DGEX...CANADIAN AND OPERATIONAL GFS FARTHER N. THIS SHOULD GIVE US A LTL BREAK TO START THE PD...BUT QUESTION LOOKS MOOT BY TUE NGT THROUGH THE RMNDR OF THE WEEK AS MOST SOLUTIONS SLIDE BNDRY RIGHT INTO THE HEART OF IA WITH PTN LOCKED INTO WRN TROF/ERN RDG. HAVE EITHER INTRODUCED POPS OR RAISED A BIT FURTHER INTO CHC CATEGORY DRNG THIS PD AS SUGGESTED BY ENSEMBLE MOS AND PCPN PROBS. WL LEAN TWRD RECENT N.A. MDL SOLUTIONS AS ECMWF DOES NOT SUPPORT GFS/DGEX/CANADIAN OR ASSOCD ENSEMBLES WITH WRN TROF BEING SO FAR W ARND 00Z FRI. THIS PD COULD BE QUITE WET WITH FLOODING POTENTIAL...SPCLLY IF WE TAKE A FEW EVENTS THIS WEEKEND. LOOKS LIKE PROLONGED PD OF UPR LVL SWLY FLOW. LLJ DOES NOT APPR TO BE TOO STG AND GFS CONTS TO OVERDO LOW LVL MSTR...BUT ELEVATED ISENT LIFT CERTAINLY PRESENT OVER BNDRY. DO NOT FEEL ESF WARRANTED YET BUT SITUATION WL HAVE TO BE WATCHED...MORE BECAUSE OF REPETITIVENESS RATHER THAN JUICED AMS. DID NOT MAKE TOO MANY CHGS TO TEMPS. DID BACK OFF A BIT ON MAXES HWVR BY MIDWEEK WITH PTN WETTER THAN XPCD YDA. SEE NO REASON FOR TEMPS NOT TO HOVER ARND CLIMO WHICH IS CLOSE TO GFS MOS AND ENSEMBLE MEAN. && .DMX WATCHES/WARNINGS/ADVISORIES...NONE. && $$ FAB/BSS ia AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 450 PM EDT FRI JUN 3 2005 .DISCUSSION... MAIN FCST CONCERNS ARE SHRA/TSRA POTENTIAL/STRENGTH THROUGH THE WEEKEND. WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL LOW OVER SRN SASK WITH A DOWNSTREAM RDG OVER THE GREAT LAKES. STRONGEST UPSTREAM SHRTWVS/VORTS WERE LOCATED OVER SRN UT AND OVER THE TX/OK PANHANDLE WHILE A WEAKER SHRTWV WAS MOVING NE OUT OF SW MN. AT THE SFC...SE FLOW PREVAILED BTWN HIGH PRES OVER THE ERN LAKES AND DEVELOPING LOW PRES OVER THE PLAINS. VIS LOOP INDICATED HIGH CLOUDS SPREADING INTO THE W HALF OF UPR MI WHILE INCREASING MOISTURE ADVECTION HAD BROUGHT A LOWER CLOUD DECK TO A A MNM-GLR LINE. TONIGHT...SATELLITE TRENDS AND NAM 925-850 MB RH PROGS...WHICH HAS DECENT GRASP OF CURRENT SITUATION...SUGGEST CLOUD DECK TO THE SOUTH WILL CONTINUE SO SPREAD NORTHWARD ACRS UPR MI. INCREASE IN CLOUDS SHOULD KEEP TEMPS FROM DROPPING OFF TOO MUCH EVEN THOUGH WINDS SHOULD AGAIN BECOME LGT SE OR VRBL OVERNIGHT. SAT INTO NIGHT...MDLS SUGGEST THAT REMNANTS OF THE SRN PLAINS SHRTWV WILL RIDE NE INTO THE UPR MS VALLEY BY LATE SAT...BRUSHING THE WRN LAKES BY SAT NIGHT. EVEN THOUGH THE DEVELOPMENT OF THE PLAINS MID LEVEL AND SFC LOW OVER ERN SD BY 00Z/SUN MAY BE OVERDONE BY THE GLBL MDLS (ESPECIALLY THE GFS) DUE TO CONVECTIVE FEEDBACK(PER HPC DISC)...THE FCST STILL LEANED MORE TOWARD THE GFS SOLUTION WITH THE ONSET OF PCPN AS THE NAM STILL SEEMS TOO EAGER TO BRING DEEPER MOISTURE EAST INTO UPR MI...GIVEN THE RELATIVELY HIGH AMPLITUDE PATTERN. BY SAT NIGHT...COMBINATION OF STRENGTHENING LOW LEVEL JET WITH H8 WINDS TO AROUND 40 KT AND UPPER LEVEL DIFFLUENCE/DIV SHOULD BRING BEST PCPN CHANCE ACRS UPR MI. LOW LEVEL THETA-E RDG AND ASSOCIATED INSTABILITY INTO UPR MI WITH H8 DEWPOINTS TO AROUND 12C (SHOWALTER -3) WILL ALSO BRING SOME TSTMS TO THE AREA. HOWEVER...DEEP LYR SHEAR LOOKS MARGINAL TO SUPPORT MORE ORGANIZED STORMS. SUN...MDL DIFFERENCES BECOME MORE APPARENT AS THE GFS BRINGS THE STACKED LOW JUST N OF KINL BY 00Z/MON WHILE THE WEAKER NAM PUSHES THE LOW FARTHER NE. EITHER SCENARIO WILL LEAVE UPPER MI WITH UNSTABLE AIR OVER THE AREA AHEAD OF THE SFC FRONT. MODIFIED MDL SNDGS WITH MID TO UPPER 70S AND LOW TO MID 60S DEWPOINTS WOULD GIVE CAPE VALUES IN THE 500-1000 J/KG RANGE WHILE BETTER SHEAR SPREADS OVER THE AREA. SO...BETTER SEVERE THREAT WOULD BE EXPECTED SUN...ESPECIALLY IF CLOUDS THIN ENOUGH FOR DECENT INSOLATION AND TRAILING SHRTWV LOBE AROUND THE MID LVL LOW COINCIDES WITH DIURNAL MAX. MON...THE GFS/UKMET SUGGEST THAT THE MID LEVEL AND SFC LOW WILL MOVE FROM NRN ONTARIO TOWARD JAMES BAY LEAVING A DRIER WRLY FLOW ACRS UPR MI. SINCE GFS MDL SNDGS SHOW RELATIVELY DRY/STABLE PROFILE...THE SHRA/TSRA CHANCES WERE REMOVED. TUE-FRI...LACK OF MODEL CONTINUITY AND SIGNIFICANT MDL DIFFERENCES LEAD TO LOW CONFIDENCE THROUGH THIS PERIOD. WHILE THERE IS BASIC AGREEMENT WITH THE GENERAL PATTERN OF A WRN TROF AND ERN RDG...PCPN CHANCES HINGE ON POSITION OF THE MAIN SFC FRONTAL BOUNDARY. WHILE THE 00Z ENS MEAN WOULD SUGGEST THAT THAT THIS FEATURE WOULD MOVE FROM THE VCNTY OF THE WRN LAKES TUE TO MAINLY S OF THE AREA...THE 00Z/06Z/12Z OPERATIONAL GFS AND CANADIAN GLBL STILL SHOW A FLATTER ERN RDG WITH THE FRONT CLOSE ENOUGH TO THE AREA FOR SHRA/TSRA THROUGH MUCH OF THE PERIOD. FOR NOW...THE FCST REFLECTS A COMPROMISE BTWN THE OPERATIONAL AND ENS MEAN WITH UNSETTLED WEATHER AND DRYING TREND TOWARD THE END OF THE WEEK WITH FRONT SAGGING SOUTH WITH MORE CONFLUENT MID LEVEL FLOW OVER THE REGION. && .MQT...WATCHES/WARNINGS/ADVISORIES...NONE. && $$ JLB mi AREA FORECAST DISCUSSION...CORRECTION TO ADD FLOOD WATCH POINTS NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO 322 PM CDT FRI JUN 3 2005 .DISCUSSION... COMPLEX WEATHER SITUATION TO EVOLVE OVER THE NEXT 36 HOURS. SHOWER AND THUNDERSTORM ACTIVITY CONTINUES TO TEASE THE WESTERN EDGES OF THE FORECAST AREA THIS AFTERNOON. THE ACTIVITY HAS BECOME MORE ORGANIZED ACROSS SOUTHEAST KANSAS...ALONG THE EDGE OF THE INSTABILITY AXIS IN THE VICINITY OF THE OUTFLOW BOUNDARY FROM THE OVERNIGHT CONVECTION. ANTICIPATE THIS CLUSTER OF THUNDERSTORMS TO TRACK ACROSS THE SOUTHWESTERN CWA DURING THE LATE AFTERNOON HOURS...ALTHOUGH IT WILL LIKELY LOSE INTENSITY AS IT ENCOUNTERS MORE STABLE AIRMASS ACROSS THE CWA. AFTERNOON WATER VAPOR IMAGERY SHOWS THE NEXT SHORTWAVE OF INTEREST OVER THE TEXAS/OKLAHOMA PANHANDLE. EXPECT ANOTHER CONVECTIVE COMPLEX TO EVOLVE TONIGHT AS THE AFOREMENTIONED SHORTWAVE LIFTS NORTHEAST ACROSS KANSAS...AND A 40 KNOT LOW LEVEL JET INDUCES A WEST-EAST ORIENTED MOISTURE CONVERGENCE AXIS ACROSS THE FORECAST AREA. THIS WILL YIELD AN ELEVATED HEAVY RAINFALL THREAT...ALTHOUGH CANNOT RULE OUT ISOLATED SEVERE ELEVATED THUNDERSTORMS PRODUCING HAIL AS WELL. MOST PRIMED AREA FOR FLOODING WILL BE AREAS ALONG AND WEST OF A BETHANY TO RICHMOND TO BUTLER LINE...WHERE A FLOOD WATCH IS IN EFFECT UNTIL NOON SATURDAY. HAVE PLACED THE HIGHEST POPS BETWEEN THE HOURS OF MIDNIGHT AND 7 AM. SATURDAY APPEARS AS IT WILL BE ANOTHER ACTIVE DAY...ESPECIALLY DURING THE LATE AFTERNOON AND EVENING HOURS. BOTH NAM AND GFS SOLUTIONS PROG THE DEVELOPMENT OF A FAIRLY HEALTHY SHORTWAVE...AND ASSOCIATED SURFACE CYCLOGENESIS. PARAMETERS POINT TOWARD A POTENTIAL SEVERE WEATHER EVENT...WITH PROGGED CAPES OF 2500 J/KG...AND 700-500MB LAPSE RATES OF 8 C/KM IN ADVANCE OF THE APPROACHING FRONT. DEEP LAYER SHEAR WILL INCREASE AND THE CAP WILL LIKELY SUFFICIENTLY ERODE BY LATE AFTERNOON AS THE SHORTWAVE TROUGH APPROACHES...ESPECIALLY ACROSS NORTHEAST KANSAS AND NORTHWEST MISSOURI. THERE IS STILL SOME MODEL/FORECASTER UNCERTAINTY ON THE SURFACE LOW DEVELOPMENT...SO WILL NEED TO CONTINUE MONITORING THE SYSTEM EVOLUTION AND ATTENDANT TORNADO THREAT. THE GFS, CANADIAN, AND GFS MODELS SUGGEST THAT THERE WILL BE A SHORTWAVE RIDGE BUILD OVER KANSAS AND MISSOURI MONDAY AND TUESDAY. I HAVE LOWERED PRECIPITATION CHANCES ACCORDINGLY. IT LOOKS LIKE THE PATTERN BECOMES MORE CONDUCIVE FOR STORMS WEDNESDAY, THURSDAY, AND FRIDAY AS HEIGHTS FALL OVER KANSAS AND NEBRASKA. THE PATTERN ADVERTISED FOR THE END OF THE WEEK LOOKS VERY SIMILAR TO WHAT IS EXPECTED THIS WEEKEND WITH AN EAST WEST STATIONARY BOUNDARY OVER THE REGION AND DISTURBANCES MOVING THROUGH THE SOUTHWEST FLOW. SCHMIT/KOCH && .PREV DISCUSSION... 330 AM CDT FRI... MESSY...MESSY...MESSY. THAT IS WHAT THE NEXT 3 DAYS WILL BRING AS SEVERAL UPPER LEVEL DISTURBANCES/MCS FEATURES WILL MAKE IT A JOY TO HIT TEMPERATURE FORECASTS AND BREAK DOWN ARRIVAL OF CONVECTION. LARGE SCALE PATTERN IS DENOTED BY LARGE UPPER TROUGH OVER THE NORTHERN ROCKIES WITH SHORTWAVE OVER NV ROTATING UNDERNEATH...THIS FEATURE WILL BEAR WATCHING FOR SEVERE POTENTIAL ON SATURDAY AFTERNOON AND EVENING. SHARP SHORTWAVE TROUGH CROSSING NORTHERN MEXICO WILL ALSO BE A PLAYER FOR CONVECTION TONIGHT. IN THE SHORT TERM MCS MOVING INTO EASTERN NEBRASKA AND TRAILING BACK INTO CENTRAL KS HAS FINALLY STARTED TO TURN MORE SOUTHEAST ON THE SOUTHERN END. HOWEVER...MID LEVEL CAP HAS THWARTED DEVELOPMENT OF CONVECTION ANY FURTHER SOUTHWEST. STILL EXPECT THE SOUTHERN PORTION OF MCS TO MOVE INTO NORTHWEST AND PORTIONS OF WEST CENTRAL MO SHORTLY AFTER 12Z. SINCE MCS WILL BE MOVING INTO A LESS FAVORABLE ENVIRONMENT...I.E. MORE STABLE/LESS MOISTURE...EXPECT CONVECTION TO WEAKEN AS IT MOVES INTO FAR WESTERN CWA THIS MORNING AS NOTED BY 00Z GFS AND LATEST RUC QPF. HAVE DOUBTS AS TO WHETHER OR NOT THERE WILL BE REDEVELOPMENT OF CONVECTION THIS AFTERNOON TIED TO REMNANTS OF MCS AS EXTENSIVE CLOUD DEBRIS WILL LIMIT AFTERNOON HEATING. HAVE LOWERED HIGH TEMPERATURES BY A CATEGORY OVER WESTERN CWA FOR TODAY. SEVERE POTENTIAL ALSO LIMITED DUE TO THE EXPECTED WIDESPREAD CLOUD COVER AND MARGINAL INSTABILITY. HAVE BUMPED POPS UP FOR TONIGHT TO LIKELY CATEGORY OVER ALL BUT FAR EASTERN CWA AS SHORTWAVE OVER NORTHERN MEXICO LIFTS NORTHEAST. 850MB LOW LEVEL JET EXPECTED TO VEER THIS EVENING AND DRAW DEEPER MOISTURE NORTHWARD AND AHEAD OF THIS SHORTWAVE. PRECIPITABLE WATER VALUES WILL BE ON THE INCREASE TONIGHT AND COULD HAVE A HYDRO PROBLEM OVER FAR WESTERN CWA WHERE FFG VALUES ARE AROUND 1.5 INCHES/1 HOUR. HAVE KEPT LOW CHANCE POPS IN FOR SATURDAY AS MESOSCALE BOUNDARIES LEFT OVER FROM TONIGHTS CONVECTION COULD PLAY A ROLE IN SCATTERED CONVECTION. HOWEVER...BETTER BET FOR CONVECTION STARTS LATE SATURDAY AFTERNOON OR BETTER YET SATURDAY EVENING AS SHORTWAVE NOW ROLLING THROUGH NV IS PROGGED TO SHARPEN AS IT LIFTS NORTHEAST THROUGH KS. A STALLED COLD FRONT IS FORECAST TO BE NEAR NORTHWEST MO BY SATURDAY AFTERNOON WITH A SOUTHERLY LOW LEVEL JET REFORMING OVER EASTERN KS. BY THIS TIME THE LOW LEVEL JET WILL HAVE BEEN ABLE TO TRANSPORT UPPER 60 DEWPOINTS INTO THE REGION. NAM APPEARS TO BE OVER FORECASTING THE LOW LEVEL DEWPOINTS...AND THUS INSTABILITY. NONETHELESS EXPECT TO SEE MUCAPES WELL IN EXCESS OF 3000 J/KG ON SATURDAY WITH SUFFICIENT 0-6KM SHEAR TO SUPPORT SEVERE CONVECTION. HAVE MADE MINOR CHANGES TO REST OF FORECAST WITH THE MOST NOTABLE LOWERING RAIN CHANCES ON MONDAY TO SLIGHT CATEGORY. MJ 809 PM CDT THU... MINOR REVISION TO SLOW DOWN THUNDERSTORM ARRIVAL A BIT IN THE NORTHWEST PART OF FORECAST AREA TONIGHT. ONGOING STORMS STILL WELL WEST OF REGION...AND UPPER AIR THIS EVENING SHOWING QUITE A BIT OF DRY AIR LEFT OVER IN EASTERN KANSAS IN WAKE OF CONVECTION THAT MOVED THROUGH THIS AFTERNOON...SO EXPECT ANY RETURN FLOW SET UP NOT TO OCCUR UNTIL LATE TONIGHT. THUS WILL TAKE OUT ANY MENTION OF EVENING POPS. PC && .EAX WATCHES/WARNINGS/ADVISORIES... MO...FLOOD WATCH UNTIL NOON SATURDAY FOR MOZ001-MOZ002-MOZ003-MOZ004- MOZ005-MOZ011-MOZ012-MOZ013-MOZ014-MOZ020-MOZ021-MOZ022- MOZ028-MOZ029-MOZ030-MOZ037-MOZ043-MOZ053. KS...FLOOD WATCH UNTIL NOON SATURDAY FOR KSZ025-KSZ057-KSZ060-KSZ102- KSZ103-KSZ104-KSZ105. $$ mo AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE ABERDEEN SD 300 PM CDT FRI JUN 3 2005 .SHORT TERM...TONIGHT THROUGH MONDAY NIGHT SOME PROBLEMS WITH THE SHORT TERM MODELS TODAY. BIGGEST CONCERN IS FOR TONIGHT AS UPPER WAVE APPROACHES FROM THE SOUTH. HAVE DECIDED TO GO WITH A MODIFIED GFS SOLUTION. AT THE SURFACE LOW PRESSURE NORTH OF MONTANA IS CAPTURED UNDER THE H5 UPPER LEVEL LOW. A FRONTAL BOUNDARY ARCS FROM THAT LOW TO A WEAK LOW IN SOUTHERN NORTH DAKOTA AND THEN CONTINUES SOUTH INTO NEBRASKA. THIS FRONT IS SLOWLY MOVING EAST. 60+ DEWPOINTS ARE POOLING TO THE EAST OF THE BOUNDARY WITH 40-50 DEWPOINTS FARTHER WEST. CONVECTION IS STARTING TO SHOW UP ALONG THIS BOUNDARY. 17Z RUC SHOWS MIXED LAYER CAPES APPROACHING 1100 J/KG WITH CONVECTIVE INHIBITION MOSTLY GONE. AN AREA OF CONVERGENCE NEAR ABERDEEN IS SHOWING UP ON LATEST WSR-88D IMAGE WITH INDIVIDUAL ELEMENTS MOVING NORTH. ANOTHER AREA OF LOW LEVEL ACTIVITY IS ALONG THE EAST EDGE OF THIS FORECAST AREA WHICH APPEARS TO BE A REFLECTION OF AN INCREASING LOW LEVEL JET. EXPECT THIS ACTIVITY TO CONTINUE TO DEVELOP THIS EVENING. MODELS DIFFER TONIGHT AS ETA DAMPENS UPPER WAVE APPROACHING FROM THE SOUTH AND GFS SEEMS TO OVER DEVELOP IT. FAVOR A BLENDED MODEL SOLUTION AS GFS HAS A BETTER HANDLE ON INCREASING H85 JET AS DEPICTED ON WOOD LAKE MINNESOTA PROFILER BUT SUFFERS FROM FEEDBACK TONIGHT. TOMORROW DURING THE MORNING AN H5 WAVE ROTATES A SURFACE LOW THROUGH EASTERN SOUTH DAKOTA. EXPECT CONVECTION TO CONTINUE THROUGH THIS TIME. IT WILL FINALLY END LATE SATURDAY AND AGAIN BE POSSIBLE SUNDAY WITH AFTERNOON HEATING. HAVE A CONCERN FOR CONVECTION FORMING ALONG FRONTAL BOUNDARY DRAPED ACROSS NORTHEAST PART OF THIS AREA. AFTER LAST NIGHTS HEAVY RAINS FLASH FLOOD GUIDANCE IS JUST OVER ONE INCH. EXPECT THIS VALUE IS POSSIBLE TONIGHT BUT WILL NOT ISSUE A FLOOD WATCH AT THIS TIME. WILL MONITOR STORM TOTAL PRECIPITATION AS AREA MOVES EAST. .LONG TERM...TUESDAY THROUGH FRIDAY GOOD AGREEMENT AMONGST THE MDLS WITH THE FLOW PATTERN FOR TUES-FRI. BIG UPPER LOW DROPS INTO THE SW US WITH UPPER RIDGING DOWNSTREAM. WITH SETUP...WARM...MOIST AND UNSTABLE AIR WILL REMAIN OVER THE ABR CWA THROUGH THE EXTENDED. S/WS EJECTING OVER THE REGION INTERACTING WITH AN EAST/WEST THERMAL ZONE WILL BRING CHCS OF TSRAS TO THE CWA. AT THIS POINT...IT LOOKS LIKE S/WS WILL AFFECT THE CWA TUES AFTN THROUGH WED NIGHT. WILL LEAVE POPS AS IS FOR NOW FOR THIS TIME PERIOD AND WILL ALSO LEAVE THURSDAY AND FRIDAY DRY FOR NOW. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. && $$ KEEFE/MOHR sd