AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TALLAHASSEE FL 920 AM EDT THU JUN 22 2006 .PUBLIC... 13Z WATER VAPOR AND RUC ANALYSIS SHOWS FAIRLY ZONAL FLOW ASSOCIATED WITH THE NORTHERN STREAM WITH JUST A FEW KINKS IN THE FLOW RELATED TO PROPAGATING MCS CLUSTERS ACROSS PA AND ANOTHER OVER IL. SOUTHEAST CONUS UNDER CONTROL OF LARGE DOMINANT UPPER RIDGE WHICH WILL ONCE AGAIN PROVIDE THE AREA WITH VERY WARM TO HOT AFTERNOON TEMPERATURES. STILL EXPECTING MIDDLE TO UPPER 90S MOST LOCATIONS AWAY FROM THE COAST. A FEW LOCATIONS...ESPECIALLY ACROSS OUR AL & GA ZONES MAY ONCE AGAIN FLIRT WITH THE CENTURY MARK. MEAN 1000-700 MB FLOW REMAINS A WEAK E-NE FLOW OR A TYPE 2 REGIME. CURRENT POPS AROUND 20% ARE JUSTIFIED WITH THIS REGIME...SIMILAR TO WHAT WAS SEEN ON WEDNESDAY AFTERNOON. HOWEVER...MODIFIED 12Z KTLH SOUNDING IS SHOWING A BIT BETTER DYNAMICS AND MOISTURE FOR THIS AFTERNOON THAN WHAT WAS SEEN YESTERDAY. MODIFYING TO ACCOUNT FOR FORECAST CONDITIONS MID TO LATE AFTERNOON YIELDS BETWEEN 2000-2500 J/KG OF SURFACE BASED CAPE...AN LI OF AROUND -6...AND A PW OF AROUND 1.7 INCHES (NEAR NORMAL FOR THIS TIME OF YEAR). TWO FOCUSING MECHANISMS WILL BE THE AFTERNOON SEA-BREEZE CONVERGENCE AND A VERY WEAK SURFACE TROUGH STILL ANALYZED ACROSS SOUTHERN GEORGIA (AGAIN VERY SIMILAR TO SURFACE FEATURES FROM YESTERDAY). AT THIS POINT IN TIME WILL NOT MAKE ANY MAJOR CHANGES TO THE AFTERNOON AND EVENING POPS AS UPPER RIDGE DIRECTLY OVERHEAD WILL HAVE SOME SUPPRESSING EFFECTS ON THE DYNAMICS. HOWEVER...ANY STORMS THAT DO GET GOING THIS AFTERNOON WILL CERTAINLY BE ABLE TO PRODUCE LOCALLY VERY HEAVY RAINS...AND WITH THE WEAK FLOW MAY BE RATHER SLOW MOVERS. && .MARINE... SURFACE RIDGE ACROSS THE COASTAL WATERS WILL PROVIDE ANOTHER DAY OF GENERALLY LIGHT WINDS AND LOW SEAS. WINDS STARING OUT GENERALLY 5 TO 10 KNOTS THIS MORNING AND NOT EXPECTING MUCH CHANGE INTO THE AFTERNOON AND EVENING HOURS. AS IS TYPICAL IN THE SUMMER MONTHS...SOME ENHANCEMENT OF ONSHORE WINDS IS EXPECTED WITH THE AFTERNOON SEA BREEZE WITHIN ABOUT 10 MILES OF THE COAST. && .AVIATION... AFTER BRIEF PERIODS OF MVFR VISIBILITY AT TLH AND VLD THIS MORNING...VFR CONDITIONS ARE EXPECTED FOR THE REMAINDER OF TODAY. ISOLATED THUNDERSTORMS WILL DEVELOP THIS AFTERNOON...BUT THE RAIN CHANCES ARE TOO LOW TO INCLUDE THEIR MENTION IN OUR TAFS. BRIEF IFR-MVFR CEILINGS AND VISIBILITY...AS WELL AS WIND GUSTS TO 25 KT...WILL OCCUR IN THESE STORMS. WINDS WILL BE LIGHT AND VARIABLE...BECOMING SOUTHWEST 5 TO 10 KT THIS AFTERNOON. && .FIRE WEATHER... AN UPPER LEVEL RIDGE OF HIGH PRESSURE WILL KEEP HOT AND FAIRLY DRY WEATHER OVER THE AREA THIS AFTERNOON...BUT IS NOT EXPECTED TO BE DRY ENOUGH TO ALLOW FOR RED FLAG CONDITIONS. A FEW WIDELY SCATTERED AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS ARE EXPECTED. OVER THE WEEKEND...LOOK FOR INCREASING MOISTURE TO RETURN TO THE REGION WITH BETTER CHANCES FOR AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS. && .TAE WATCHES/WARNINGS/ADVISORIES... AL...NONE. GA...NONE. FL...NONE. && $$ AVIATION...FOURNIER REST OF DISCUSSION...BAM fl AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL 630 PM CDT THU JUN 22 2006 .DISCUSSION FOR AFTERNOON ZFP/GRIDS... 309 PM CDT MCV ASSOCIATED WITH MORNING CONVECTIVE COMPLEX HAS PULLED OUT OF THE FCST AREA THIS AFTN...WITH SUBSIDENCE PROVIDING A FAIR AMOUNT OF SUNSHINE ACROSS NRN IL/NW IND. 18 UTC SOUNDING FROM ILX AND RECENT ACARS OBSERVATIONS OUT OF KRFD/KORD INDICATE INVERSION ASSOCIATED WITH THIS SINKING AIR...WITH WARMING IN 750-850 HPA LAYER KEEPING CAP ON ANY RENEWED CONVECTION AS WELL AS PREVENTING FULL POTENTIAL OF AFTN WARMING AT SFC. MAIN QUESTION NOW IS DEGREE OF CONVECTIVE POTENTIAL TONIGHT AS SECONDARY SFC TROUGH/COLD FRONT PUSHES SOUTH INTO REGION AS SHORT WAVE TROUGH DIGS SOUTHEAST FROM MN...AND ALSO FOR SOUTHERN PARTS OF THE FCST AREA AS SHORT WAVE/MCS OVER MO MOVES SLOWLY EAST ACROSS IL. FOR THE FORMER...LATEST SPC RUC MESOANALYSIS TOOLS INDICATE WEAK INSTABILITY DVLPG SRN WI SOUTHWEST THROUGH IA...WHERE SLIGHTLY HIGHER SFC DEWPOINTS EXIST ALONG SFC BOUNDARY. VIS SAT PICS SHOW SOME ENHANCED CU DVLPG OVER WRN IA...AND OVER ECNTRL WI. GIVEN THAT THIS BOUNDARY NOT EXPECTED TO ARRIVE IN NRN IL/NW IND UNTIL LATE EVENING AT DIURNALLY UNFAVORABLE TIME FOR LOW LEVEL INSTABILITY...AND CAPPING ALREADY NOTED DURG AFTN HOURS AHEAD OF IT WILL MAINTAIN DRY FORECAST FOR NRN PARTS OF CWA. FOR SRN PARTS ALSO NOT IMPRESSED WITH ABILITY TO RECOVER THIS AFTN...THOUGH AM CONCERNED THAT NORTHERN EDGE OF CURRENT MCS PRECIP WILL BRUSH SOUTHERN COUNTIES OVERNIGHT AS WAVE PUSHES EAST INTO TAIL BROAD UPPER TROUGH. BASED ON THIS WILL MAINTAIN A LOW POP CHANCE FOR OUR SOUTHERN COUNTIES OVRNGT AND INTO THE MORNING HOURS ON FRI. MID LVL TROUGH AXIS PUSHES EAST IN THE AFTN...DECREASING PCPN THREAT THERE. SFC HIGH PRESSURE THEN BUILDS ACROSS GRTLKS FRI AFTN THROUGH SATURDAY RESULTING IN DRY QUITE WX FOR THE START OF THE WEEKEND. NEXT POTENTIAL PRECIP THREAT OCCURS SUNDAY AFTN...AS NEXT SHORT WAVE DROPS SOUTHEAST ACROSS UPPER MS VLY/WI IN NORTHWEST FLOW ALFT. APPEARS AT THIS TIME POTENTIAL WOULD MAINLY BE DIURNAL ISOLATED/SCT TRW SUN AFTN/EARLY EVENING UNDER COOL POOL ALOFT AND WEAK LLVL WAA ABOVE BOUNDARY LAYER...AS GFS FCST SOUNDINGS INDICATE ONLY MARGINAL INSTABILITY AND WEAK LLVL WIND FIELD IN VCNTY OF WEAKENING SFC RIDGE AXIS. BASED ON THIS WILL ONLY HAVE LOW CHC POP MAINLY NRN 1/2 OF CWA SUN AFTN THROUGH ABOUT SUNSET. OTHERWISE GOING FCST APPEARS TO BE HOLDING UP VERY WELL...AND ONLY A FEW MINOR TEMP TWEAKS WERE MADE. ECMWF/GFS BEGIN TO DIFFER BY MID NEXT WEEK WITH HANDLING OF UPPER TROUGH OVER NOAM...SO WILL NOT MAKE ANY REAL MAJOR CHANGES TO GOING DRY FCST ATTM. RATZER && .AVIATION... 630 PM CDT RE 00Z TAFORS...WNDS HAVE VEERED TO WNW-NW ACROSS AREA LAST FEW HRS AS MAIN SFC BNDRY CONTS TO SLOLY SAG SEWRD...CURRENTLY FM KFWA TO KIND TO KMVN...THO WNDS JUST UPSTRM BACKING TO WSW-W AHEAD OF WK SFC TROF REFLECTION OF MID LVL TROF OVR SW WI AND ERN IA. FURTHER N ACROSS CNTRL WI IA IS ANOTHER WSHFT LN. HAS BEEN SOMEWHAT SLO TO ADVANCE SWRD DURG LATE AFTERNOON/ERLY EVE BUT SHUD PICKUP SOME SPEED AS WI-IA S/WV TROF MOVS ACROSS TERMINALS DURG THIS EVE...WHICH WILL ALSO CLR OUT MID AND HI CIGS. SFC RDG ACROSS N WOODS AND NRN GRTLKS SETTLES INTO MID MS VALLEY AND CNTRL GRTLKS BY 00Z SAT. DRYING...SUBSIDENCE AND STABALIZING EFFECT OF FLO OF LK MI SHUD LIMIT CU/SC DVLPMNT ON FRI. TRS && .LOT WATCHES/WARNINGS/ADVISORIES... .IL...NONE. .IN...NONE. .LM...LMZ740>745 SC.Y 060623T0800Z-060623T2300Z && $$ il AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL 309 PM CDT THU JUN 22 2006 .DISCUSSION FOR AFTERNOON ZFP/GRIDS... MCV ASSOCIATED WITH MORNING CONVECTIVE COMPLEX HAS PULLED OUT OF THE FCST AREA THIS AFTN...WITH SUBSIDENCE PROVIDING A FAIR AMOUNT OF SUNSHINE ACROSS NRN IL/NW IND. 18 UTC SOUNDING FROM ILX AND RECENT ACARS OBSERVATIONS OUT OF KRFD/KORD INDICATE INVERSION ASSOCIATED WITH THIS SINKING AIR...WITH WARMING IN 750-850 HPA LAYER KEEPING CAP ON ANY RENEWED CONVECTION AS WELL AS PREVENTING FULL POTENTIAL OF AFTN WARMING AT SFC. MAIN QUESTION NOW IS DEGREE OF CONVECTIVE POTENTIAL TONIGHT AS SECONDARY SFC TROUGH/COLD FRONT PUSHES SOUTH INTO REGION AS SHORT WAVE TROUGH DIGS SOUTHEAST FROM MN...AND ALSO FOR SOUTHERN PARTS OF THE FCST AREA AS SHORT WAVE/MCS OVER MO MOVES SLOWLY EAST ACROSS IL. FOR THE FORMER...LATEST SPC RUC MESOANALYSIS TOOLS INDICATE WEAK INSTABILITY DVLPG SRN WI SOUTHWEST THROUGH IA...WHERE SLIGHTLY HIGHER SFC DEWPOINTS EXIST ALONG SFC BOUNDARY. VIS SAT PICS SHOW SOME ENHANCED CU DVLPG OVER WRN IA...AND OVER ECNTRL WI. GIVEN THAT THIS BOUNDARY NOT EXPECTED TO ARRIVE IN NRN IL/NW IND UNTIL LATE EVENING AT DIURNALLY UNFAVORABLE TIME FOR LOW LEVEL INSTABILITY...AND CAPPING ALREADY NOTED DURG AFTN HOURS AHEAD OF IT WILL MAINTAIN DRY FORECAST FOR NRN PARTS OF CWA. FOR SRN PARTS ALSO NOT IMPRESSED WITH ABILITY TO RECOVER THIS AFTN...THOUGH AM CONCERNED THAT NORTHERN EDGE OF CURRENT MCS PRECIP WILL BRUSH SOUTHERN COUNTIES OVERNIGHT AS WAVE PUSHES EAST INTO TAIL BROAD UPPER TROUGH. BASED ON THIS WILL MAINTAIN A LOW POP CHANCE FOR OUR SOUTHERN COUNTIES OVRNGT AND INTO THE MORNING HOURS ON FRI. MID LVL TROUGH AXIS PUSHES EAST IN THE AFTN...DECREASING PCPN THREAT THERE. SFC HIGH PRESSURE THEN BUILDS ACROSS GRTLKS FRI AFTN THROUGH SATURDAY RESULTING IN DRY QUITE WX FOR THE START OF THE WEEKEND. NEXT POTENTIAL PRECIP THREAT OCCURS SUNDAY AFTN...AS NEXT SHORT WAVE DROPS SOUTHEAST ACROSS UPPER MS VLY/WI IN NORTHWEST FLOW ALFT. APPEARS AT THIS TIME POTENTIAL WOULD MAINLY BE DIURNAL ISOLATED/SCT TRW SUN AFTN/EARLY EVENING UNDER COOL POOL ALOFT AND WEAK LLVL WAA ABOVE BOUNDARY LAYER...AS GFS FCST SOUNDINGS INDICATE ONLY MARGINAL INSTABILITY AND WEAK LLVL WIND FIELD IN VCNTY OF WEAKENING SFC RIDGE AXIS. BASED ON THIS WILL ONLY HAVE LOW CHC POP MAINLY NRN 1/2 OF CWA SUN AFTN THROUGH ABOUT SUNSET. OTHERWISE GOING FCST APPEARS TO BE HOLDING UP VERY WELL...AND ONLY A FEW MINOR TEMP TWEAKS WERE MADE. ECMWF/GFS BEGIN TO DIFFER BY MID NEXT WEEK WITH HANDLING OF UPPER TROUGH OVER NOAM...SO WILL NOT MAKE ANY REAL MAJOR CHANGES TO GOING DRY FCST ATTM. RATZER && .AVIATION DISCUSSION REGARDING 18Z TAFS... 100 PM CDT MAIN CONCERN FOR THIS TAF ISSUANCE WILL BE ON SHORT TERM WINDS...AND THEN POST-FRONTAL WINDS TONIGHT AND THE POSSIBILITY OF ANY MVFR CIGS. MESO-HIGH HAS NOW SHIFTED INTO NORTHERN INDIANA AND WINDS HAVE BEEN RATHER CHAOTIC IN THE WAKE OF THE MORNING CONVECTION. WILL CARRY A VARIABLE WINDS FOR THE FIRST FEW HOURS OF FORECAST VALID PERIOD AND THEN BECOMING WEST THIS AFTERNOON IN ADVANCE OF SURFACE TROUGH EXTENDING FROM NORTHEAST WISCONSIN INTO EASTERN IOWA. WITH LIGHTER WINDS EARLY THIS AFTERNOON SOME CONCERN THAT AN EASTERLY LAKE ENHANCED COMPONENT COULD HOLD ON A LITTLE LONGER BUT EXPECTING SOME INCREASE IN LOW LEVEL WESTERLY WIND SPEEDS IN ADVANCE OF THIS SURFACE TROUGH WHICH SHOULD ALLOW FOR WESTERLY WIND DIRECTION TO PREVAIL THROUGH MID AFTERNOON. BY LATE THIS AFTERNOON INTO EARLY THIS EVENING SHOULD SEE WINDS VEER AROUND TO NORTH AND EVENTUALLY NORTHEAST AS THIS TROUGH PASSES. WILL KEEP TAFS DRY THROUGH THE AFTERNOON WITH BETTER INSTABILITY SETTING UP WELL SOUTH OF THE TERMINALS. OUTSIDE OF FEW CU BASED AROUND 5K FT THIS AFTERNOON...JUST EXPECTING SOME LINGERING MID CLOUD IN ASSOCIATION WITH MCV TRACKING ACROSS NORTHEAST ILLINOIS FROM THE REMANTS OF THE MORNING MCS. CONCERN TONIGHT WILL THEN SHIFT TO THE POSSIBILITY OF SOME STRATOCU BEHIND THE LOW LEVEL FRONT. CURRENT SATELLITE IMAGERY/SURFACE OBS ARE INDICATING SOME MVFR CIGS ACROSS THE UPPER PENINSULA OF MICHIGAN IN STRONGER LOW LEVEL CAA REGION. STRONGEST LOW LEVEL CAA SHOULD AFFECT NORTHEAST ILLINOIS IN THE 08Z-13Z TIME FRAME SO HAVE INTRODUCED MENTION OF 2K FT STRATOCU LATE TONIGHT BUT DO NOT HAVE ENOUGH CONFIDENCE AT THIS TIME TO INTRODUCE ANY CIGS. DURING TIME OF PEAK LOW LEVEL CAA COULD SEE WIND GUSTS UP IN THE 15 TO 20 RANGE LATE TONIGHT INTO EARLY FRIDAY MORNING. SKIES WILL CLEAR DURING THE MORNING ON FRIDAY AS DRIER LOW LEVEL AIR ADVECTS INTO NORTHERN ILLINOIS WITH PERHAPS SOME CIRRUS. NDM && .LOT WATCHES/WARNINGS/ADVISORIES... .IL...NONE. .IN...NONE. .LM...NONE. && $$ il AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NORTHERN INDIANA 1255 PM EDT THU JUN 22 2006 ...SEVERE WEATHER EXPECTED TO SPREAD TO NORTHWEST OHIO LATER THIS AFTERNOON... .UPDATE NUMBER 2... FORECAST CONTINUES TO BE ON TRACK UPDATED ZONE PACKAGE FOR SEVERE THUNDERSTORM WATCH NUMBER 541 INCLUDING ALL OF OUR OHIO COUNTIES. EXTENDED LIKELY POPS INTO THIS EVENING FOR OHIO COUNTIES AS WELL. && .AVIATION... COMPLEX WEATHER SITUATION THIS AFTERNOON. A LINE OF STRONG TO SEVERE THUNDERSTORMS ARE CROSSING NORTHERN INDIANA AT THIS TIME. THE MAIN THRUST IS SOUTH OF THE TERMINALS AT THIS TIME...BUT THUNDERSTORM DEVELOPMENT IS QUITE LIKELY AT FORT WAYNE TERMINAL. KEPT THUNDER MENTION IN FORT WAYNE TAF. THUNDERSTORMS SHOULD BE EAST OF THE SOUTH BEND TERMINAL BY 18Z WITH NO MORE THUNDER EXPECTED FOR THIS TAF ISSUANCE TIME PERIOD. CEILINGS AND VISIBILITY WILL REMAIN VFR FOR THE MOST PART...BUT WILL DROP TO IFR VISIBILITY IN THUNDERSTORMS. THUNDERSTORMS WILL BE EAST OF BOTH TERMINALS BY 23Z WITH VFR CONDITIONS RETURNING ACROSS THE AREA BY THIS EVENING. THERE MAY BE A CHANCE OF FOG LATER TONIGHT AT BOTH TERMINALS...BUT HAVE ELECTED TO KEEP IT OUT OF THE TERMINAL FORECASTS AT THIS TIME. && .UPDATE... ANOTHER COMPLEX MESOSCALE SITUATION DVLPG THIS AM W/UPSCALE TRENDS NOTED IN SMALL BUT SVR FORWARD PROPAGATING MCS NOW INTO WRN IL. LARGER SCALE SYNOPTIC SETUP REMAINS RELATIVELY UNCHANGED W/STEEP MID LVL LAPSE RATE PLUME STILL IN PLACE ACRS MIDWEST/GREAT LAKES OVERTOP SEASONABLY MOIST BNDRY LYR. QUASI-STATIONARY FNTL BNDRY EXTENDS FM CNTRL LK HURON BACK SW INTO WK SFC FNTL WAVE ANALYZED OVR NE MO AS A REFLECTION OF ROBUST MCV ACRS NE KS SPAWNED FM LAST NIGHTS CONVN. AIRMASS DOWNSTREAM OF IL ACTIVITY WILL HEAT RAPIDLY THIS MORNING UNDERNEATH THIN CIRRUS SHIELD AND WARM START. GIVEN WELL DVLPD COLD POOL IN PLACE AND DEEP...UNIDIRECTIONAL SHEAR XPC THIS CLUSTER WILL CONT TO INTENSIFY AS IT GRAVITATES EWD ACRS THE REMAINDER OF IL THROUGH THIS MORNING. THUS XPC ANOTHER OUTBREAK OF SEVERE THUNDERSTORMS POSSIBLE ACRS IN/OH PORTIONS OF CWA BY LT MORNING INTO MID AFTN. WILL UPDATE RELEVANT PRODUCTS AS NEEDED. && .PREV DISCUSSION... SHORT TERM... TODAY AND TONIGHT. HAVE GONE WITH A BLEND OF THE RUC40 AND 00Z NAM-WRF FOR THIS FCST PACKAGE. A COUPLE OF COLD FRONTS WILL AFFECT THE REGION OVER THE NEXT 24 HOURS. AT 08Z...THE FIRST COLD FRONT THAT WILL AFFECT THE REGION WAS LOCATED FROM SE ONTARIO...ACRS NRN MICHIGAN...THEN INTO FAR SE WISCONSIN. THIS FRONT WILL MOVE SLOWLY EAST TODAY...BEING LOCATED FROM ABOUT DETROIT...TO GOSHEN...IN...TO KANKAKEE IL BY 18Z...THEN FROM NEAR CLEVELAND...TO CNTRL INDIANA...THEN INTO CNTRL ILLINOIS BY 00Z THIS EVENING. THE ATMOSPHERE AHEAD OF THIS FRONT REMAINS QUITE UNSTABLE AS EXHIBITED BY CURRENT MUCAPES OF 1000 J/KG TO 2000 J/KG. AS THE FRONT MOVES ACRS THE REGION...A WEAK S/WV WILL APCH FROM THE SOUTHWEST...MOVING ACRS THE FCST AREA BETWEEN 18Z AND 00Z. ALTHOUGH LOW LVL CONVERGENCE ALONG AND AHEAD OF THE FRONT WILL BE FAIRLY WEAK...THE S/WV AND THE VERY UNSTABLE AIR MASS (SBCAPES NEAR LIMA OHIO ARE FORECAST TO BE NEAR 3000 J/KG THIS AFTN) WILL BE ENOUGH TO KICK OF SHOWERS AND THUNDERSTORMS. THERE IS SOME CONCERN THAT THE SHOWER AND THUNDERSTORM THREAT MAY END ACRS THE FAR NW CWFA THIS AFTN AS DRIER AIR FROM 925 MB TO 850 MB MOVES INTO THIS AREA. DO NOT HAVE THE CONFIDENCE TO GO DRY JUST YET...SO WILL LAYER POPS FROM 20 PERCENT FAR NW TO 50 PERCENT SE. THIS WILL ALLOW DAY SHIFT TO FINE TUNE FCST. HIGHS TODAY WILL RANGE FROM AROUND 80 ALONG THE LAKE MICHIGAN SHORELINE TO THE UPPER 80S ACRS THE SOUTH AND SOUTHEAST. FOR TONIGHT...FIRST COLD FRONT WILL SLOWLY SAG SOUTH. ANOTHER COLD FRONT WILL APCH THE REGION FROM THE NORTHWEST...MOVING INTO THE FCST AREA AFTER 06Z...AND THEN INTO THE SRN CWFA BY FRIDAY MORNING. SHOWERS AND THUNDERSTORMS SHOULD STILL BE ONGOING ALONG AND AHEAD OF THE FIRST COLD FRONT THIS EVENING...WHILE NOT MUCH IS EXPECTED IN THE WAY OF PCPN AHEAD OF THE NEXT FRONT. WILL LAYER POPS FROM 20 PERCENT NORTH TO 50 SOUTH FOR THE EVENING HOURS...THEN JUST A 30 PERCENT CHC IN THE FAR SOUTH AFTER MIDNIGHT. DRIER AIR WILL SLOWLY FILTER INTO THE REGION. LOWS TONIGHT WILL RANGE FROM THE LOWER TO MID 60S. LONG TERM... THE CURRENT FORECAST FOR THE FRIDAY THROUGH NEXT WEDNESDAY TIME FRAME IS A DRY ONE...EXCEPT FOR THE SOUTHERN PART OF THE CWA FRIDAY MORNING. THE GFS IS CONTINUING TO BE THE WETTEST MODEL FOR FRIDAY AND OVER THE LAST FEW RUNS IT HAS KEPT THE MAIN PART OF THE RAIN TO THE SOUTH. THE GFS IS JUST CREEPING SOME QPF INTO THE SOUTHERN PART OF OUR CWA. GFS/NAM SOUNDINGS ARE SHOWING FAIRLY DEEP MOISTURE YET FOR THE SOUTHERN PART OF THE CWA FRIDAY MORNING. SO WITH A CHANCE THAT SOME LINGERING SHOWERS/STORMS COULD BE GOING ON INTO FRIDAY MORNING...HAVE PUT IN A SMALL CHANCE FOR THE SOUTHERN PART OF THE CWA WHICH COLLABORATES WELL WITH NEIGHBORING OFFICES AS WELL. SURFACE HIGH PRESSURE THEN OVER THE AREA THROUGH NEXT WEDNESDAY. THE GFS IS SHOWING A FRONT TO MOVE THROUGH MICHIGAN AND CANADA TO THE NORTH NEXT TUESDAY AND TUESDAY NIGHT...BUT FOR RIGHT NOW TO HAVE NO AFFECT ON THE CWA. THE ONLY OTHER ITEM TO NOTE IS AN UPPER LEVEL SHORTWAVE THAT GFS IS SHOWING TO MOVE THROUGH SUNDAY NIGHT THROUGH TUESDAY NIGHT. THIS SHORTWAVE HAS BEEN SHOWN TO BE DRY FOR OUR CWA...SO LEFT THIS TIME FRAME DRY. WITH NO MAJOR CHANGES IN THE PATTERN FOR THIS COMING WEEK...850MB TEMPERATURES FOR EACH AFTERNOON ARE ROUGHLY SIMILAR. SO NO BIG RANGES IN MAX TEMPERATURES FOR FRIDAY THROUGH WEDNESDAY...FORECASTED TO BE FAIRLY SIMILAR FROM DAY TO DAY. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...SEVERE THUNDERSTORM WATCH 537 INZ006-007-008-009-012>016- 017-018-020-022>024-025>027-032>034 .OH...SEVERE THUNDERSTORN WATCH 541 FOR OHZ 002-004-005-015- 016-024-025 MI...NONE. LM...NONE. && $$ UPDATE/AVIATION...GLL SHORT TERM...HICKMAN LONG TERM...BML in AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NORTHERN INDIANA 837 AM EDT THU JUN 22 2006 ...ANOTHER ACTIVE SVR WX DAY FROM LT MORNING INTO THIS AFTN ACRS MUCH OF NORTHERN INDIANA AND NORTHWEST OHIO... .UPDATE... ANOTHER COMPLEX MESOSCALE SITUATION DVLPG THIS AM W/UPSCALE TRENDS NOTED IN SMALL BUT SVR FORWARD PROPAGATING MCS NOW INTO WRN IL. LARGER SCALE SYNOPTIC SETUP REMAINS RELATIVELY UNCHANGED W/STEEP MID LVL LAPSE RATE PLUME STILL IN PLACE ACRS MIDWEST/GREAT LAKES OVERTOP SEASONABLY MOIST BNDRY LYR. QUASI-STATIONARY FNTL BNDRY EXTENDS FM CNTRL LK HURON BACK SW INTO WK SFC FNTL WAVE ANALYZED OVR NE MO AS A REFLECTION OF ROBUST MCV ACRS NE KS SPAWNED FM LAST NIGHTS CONVN. AIRMASS DOWNSTREAM OF IL ACTIVITY WILL HEAT RAPIDLY THIS MORNING UNDERNEATH THIN CIRRUS SHIELD AND WARM START. GIVEN WELL DVLPD COLD POOL IN PLACE AND DEEP...UNIDIRECTIONAL SHEAR XPC THIS CLUSTER WILL CONT TO INTENSIFY AS IT GRAVITATES EWD ACRS THE REMAINDER OF IL THROUGH THIS MORNING. THUS XPC ANOTHER OUTBREAK OF SEVERE THUNDERSTORMS POSSIBLE ACRS IN/OH PORTIONS OF CWA BY LT MORNING INTO MID AFTN. WILL UPDATE RELEVANT PRODUCTS AS NEEDED. && .AVIATION... A COLD FRONT...EXTENDING FROM CNTRL MICHIGAN INTO NRN ILLINOIS THIS MORNING...WILL MOVE SLOWLY EAST INTO THE REGION THIS AFTN. THE AIR MASS AHEAD OF THIS FRONT REMAINS VERY UNSTABLE. LOOKING TO THE WEST...WATER VAPOR AND SATELLITE IMAGERY WAS SHOWING A MCS OVER ERN IOWA. THIS FEATURE WAS MOVING EAST INTO WRN ILLINOIS. THIS MCS WAS ASSOCD WITH A MCV WHICH IS FORECAST TO MOVE ENE ACRS THE REGION BETWEEN 18Z AND 00Z. IT APPEARS THAT THE MCS HAS CAUSED A WEAK SFC LOW TO DEVELOP OVER ERN IOWA ON THE SOUTH END OF THE COLD FRONT. AM CONCERNED THAT THE FORMATION OF THE SFC LOW WILL SLOW THE COLD FRONT MORE THAN CURRENT RUC AND NAM-WRF ARE INDICATING. WITH THAT SAID...WILL INTRODUCE A TEMPO SHOWER WITH A CB MENTION AT KSBN. THE FRONT SHOULD PASS KSBN BY MID AFTERNOON...DWINDLING THE THREAT FOR PCPN THERE. FOR KFWA...THEY WILL HAVE THE BEST CHC FOR THUNDERSTORMS TODAY...AND THUS WILL EMPLOY A TEMPO TSRA BETWEEN 18Z AND 22Z...THE BEST TIME FOR THIS TO OCCUR. FOR TONIGHT...THE COLD FRONT WILL CONTINUE ITS SLOW MOVEMENT SOUTH. BELIEVE MOST OF THE CONVECTION SHOULD BE SOUTH OF KFWA BY THIS TIME...SO WILL GO DRY. ANOTHER COLD FRONT WILL PUSH INTO THE SRN GREAT LAKES TOWARD MORNING. THIS FRONT IS EXPECTED TO BE DRY...WITH A WIND SHIFT TO THE NORTH EXPECTED AT KSBN TOWARD MORNING. && .PREV DISCUSSION... SHORT TERM... TODAY AND TONIGHT. HAVE GONE WITH A BLEND OF THE RUC40 AND 00Z NAM-WRF FOR THIS FCST PACKAGE. A COUPLE OF COLD FRONTS WILL AFFECT THE REGION OVER THE NEXT 24 HOURS. AT 08Z...THE FIRST COLD FRONT THAT WILL AFFECT THE REGION WAS LOCATED FROM SE ONTARIO...ACRS NRN MICHIGAN...THEN INTO FAR SE WISCONSIN. THIS FRONT WILL MOVE SLOWLY EAST TODAY...BEING LOCATED FROM ABOUT DETROIT...TO GOSHEN...IN...TO KANKAKEE IL BY 18Z...THEN FROM NEAR CLEVELAND...TO CNTRL INDIANA...THEN INTO CNTRL ILLINOIS BY 00Z THIS EVENING. THE ATMOSPHERE AHEAD OF THIS FRONT REMAINS QUITE UNSTABLE AS EXHIBITED BY CURRENT MUCAPES OF 1000 J/KG TO 2000 J/KG. AS THE FRONT MOVES ACRS THE REGION...A WEAK S/WV WILL APCH FROM THE SOUTHWEST...MOVING ACRS THE FCST AREA BETWEEN 18Z AND 00Z. ALTHOUGH LOW LVL CONVERGENCE ALONG AND AHEAD OF THE FRONT WILL BE FAIRLY WEAK...THE S/WV AND THE VERY UNSTABLE AIR MASS (SBCAPES NEAR LIMA OHIO ARE FORECAST TO BE NEAR 3000 J/KG THIS AFTN) WILL BE ENOUGH TO KICK OF SHOWERS AND THUNDERSTORMS. THERE IS SOME CONCERN THAT THE SHOWER AND THUNDERSTORM THREAT MAY END ACRS THE FAR NW CWFA THIS AFTN AS DRIER AIR FROM 925 MB TO 850 MB MOVES INTO THIS AREA. DO NOT HAVE THE CONFIDENCE TO GO DRY JUST YET...SO WILL LAYER POPS FROM 20 PERCENT FAR NW TO 50 PERCENT SE. THIS WILL ALLOW DAY SHIFT TO FINE TUNE FCST. HIGHS TODAY WILL RANGE FROM AROUND 80 ALONG THE LAKE MICHIGAN SHORELINE TO THE UPPER 80S ACRS THE SOUTH AND SOUTHEAST. FOR TONIGHT...FIRST COLD FRONT WILL SLOWLY SAG SOUTH. ANOTHER COLD FRONT WILL APCH THE REGION FROM THE NORTHWEST...MOVING INTO THE FCST AREA AFTER 06Z...AND THEN INTO THE SRN CWFA BY FRIDAY MORNING. SHOWERS AND THUNDERSTORMS SHOULD STILL BE ONGOING ALONG AND AHEAD OF THE FIRST COLD FRONT THIS EVENING...WHILE NOT MUCH IS EXPECTED IN THE WAY OF PCPN AHEAD OF THE NEXT FRONT. WILL LAYER POPS FROM 20 PERCENT NORTH TO 50 SOUTH FOR THE EVENING HOURS...THEN JUST A 30 PERCENT CHC IN THE FAR SOUTH AFTER MIDNIGHT. DRIER AIR WILL SLOWLY FILTER INTO THE REGION. LOWS TONIGHT WILL RANGE FROM THE LOWER TO MID 60S. LONG TERM... THE CURRENT FORECAST FOR THE FRIDAY THROUGH NEXT WEDNESDAY TIME FRAME IS A DRY ONE...EXCEPT FOR THE SOUTHERN PART OF THE CWA FRIDAY MORNING. THE GFS IS CONTINUING TO BE THE WETTEST MODEL FOR FRIDAY AND OVER THE LAST FEW RUNS IT HAS KEPT THE MAIN PART OF THE RAIN TO THE SOUTH. THE GFS IS JUST CREEPING SOME QPF INTO THE SOUTHERN PART OF OUR CWA. GFS/NAM SOUNDINGS ARE SHOWING FAIRLY DEEP MOISTURE YET FOR THE SOUTHERN PART OF THE CWA FRIDAY MORNING. SO WITH A CHANCE THAT SOME LINGERING SHOWERS/STORMS COULD BE GOING ON INTO FRIDAY MORNING...HAVE PUT IN A SMALL CHANCE FOR THE SOUTHERN PART OF THE CWA WHICH COLLABORATES WELL WITH NEIGHBORING OFFICES AS WELL. SURFACE HIGH PRESSURE THEN OVER THE AREA THROUGH NEXT WEDNESDAY. THE GFS IS SHOWING A FRONT TO MOVE THROUGH MICHIGAN AND CANADA TO THE NORTH NEXT TUESDAY AND TUESDAY NIGHT...BUT FOR RIGHT NOW TO HAVE NO AFFECT ON THE CWA. THE ONLY OTHER ITEM TO NOTE IS AN UPPER LEVEL SHORTWAVE THAT GFS IS SHOWING TO MOVE THROUGH SUNDAY NIGHT THROUGH TUESDAY NIGHT. THIS SHORTWAVE HAS BEEN SHOWN TO BE DRY FOR OUR CWA...SO LEFT THIS TIME FRAME DRY. WITH NO MAJOR CHANGES IN THE PATTERN FOR THIS COMING WEEK...850MB TEMPERATURES FOR EACH AFTERNOON ARE ROUGHLY SIMILAR. SO NO BIG RANGES IN MAX TEMPERATURES FOR FRIDAY THROUGH WEDNESDAY...FORECASTED TO BE FAIRLY SIMILAR FROM DAY TO DAY. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ UPDATE...HOLSTEN SHORT TERM/AVIATION...HICKMAN LONG TERM...BML in AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NORTHERN INDIANA 710 AM EDT THU JUN 22 2006 .AVIATION... A COLD FRONT...EXTENDING FROM CNTRL MICHIGAN INTO NRN ILLINOIS THIS MORNING...WILL MOVE SLOWLY EAST INTO THE REGION THIS AFTN. THE AIR MASS AHEAD OF THIS FRONT REMAINS VERY UNSTABLE. LOOKING TO THE WEST...WATER VAPOR AND SATELLITE IMAGERY WAS SHOWING A MCS OVER ERN IOWA. THIS FEATURE WAS MOVING EAST INTO WRN ILLINOIS. THIS MCS WAS ASSOCD WITH A MCV WHICH IS FORECAST TO MOVE ENE ACRS THE REGION BETWEEN 18Z AND 00Z. IT APPEARS THAT THE MCS HAS CAUSED A WEAK SFC LOW TO DEVELOP OVER ERN IOWA ON THE SOUTH END OF THE COLD FRONT. AM CONCERNED THAT THE FORMATION OF THE SFC LOW WILL SLOW THE COLD FRONT MORE THAN CURRENT RUC AND NAM-WRF ARE INDICATING. WITH THAT SAID...WILL INTRODUCE A TEMPO SHOWER WITH A CB MENTION AT KSBN. THE FRONT SHOULD PASS KSBN BY MID AFTERNOON...DWINDLING THE THREAT FOR PCPN THERE. FOR KFWA...THEY WILL HAVE THE BEST CHC FOR THUNDERSTORMS TODAY...AND THUS WILL EMPLOY A TEMPO TSRA BETWEEN 18Z AND 22Z...THE BEST TIME FOR THIS TO OCCUR. FOR TONIGHT...THE COLD FRONT WILL CONTINUE ITS SLOW MOVEMENT SOUTH. BELIEVE MOST OF THE CONVECTION SHOULD BE SOUTH OF KFWA BY THIS TIME...SO WILL GO DRY. ANOTHER COLD FRONT WILL PUSH INTO THE SRN GREAT LAKES TOWARD MORNING. THIS FRONT IS EXPECTED TO BE DRY...WITH A WIND SHIFT TO THE NORTH EXPECTED AT KSBN TOWARD MORNING. && .PREV DISCUSSION... SHORT TERM... TODAY AND TONIGHT. HAVE GONE WITH A BLEND OF THE RUC40 AND 00Z NAM-WRF FOR THIS FCST PACKAGE. A COUPLE OF COLD FRONTS WILL AFFECT THE REGION OVER THE NEXT 24 HOURS. AT 08Z...THE FIRST COLD FRONT THAT WILL AFFECT THE REGION WAS LOCATED FROM SE ONTARIO...ACRS NRN MICHIGAN...THEN INTO FAR SE WISCONSIN. THIS FRONT WILL MOVE SLOWLY EAST TODAY...BEING LOCATED FROM ABOUT DETROIT...TO GOSHEN...IN...TO KANKAKEE IL BY 18Z...THEN FROM NEAR CLEVELAND...TO CNTRL INDIANA...THEN INTO CNTRL ILLINOIS BY 00Z THIS EVENING. THE ATMOSPHERE AHEAD OF THIS FRONT REMAINS QUITE UNSTABLE AS EXHIBITED BY CURRENT MUCAPES OF 1000 J/KG TO 2000 J/KG. AS THE FRONT MOVES ACRS THE REGION...A WEAK S/WV WILL APCH FROM THE SOUTHWEST...MOVING ACRS THE FCST AREA BETWEEN 18Z AND 00Z. ALTHOUGH LOW LVL CONVERGENCE ALONG AND AHEAD OF THE FRONT WILL BE FAIRLY WEAK...THE S/WV AND THE VERY UNSTABLE AIR MASS (SBCAPES NEAR LIMA OHIO ARE FORECAST TO BE NEAR 3000 J/KG THIS AFTN) WILL BE ENOUGH TO KICK OF SHOWERS AND THUNDERSTORMS. THERE IS SOME CONCERN THAT THE SHOWER AND THUNDERSTORM THREAT MAY END ACRS THE FAR NW CWFA THIS AFTN AS DRIER AIR FROM 925 MB TO 850 MB MOVES INTO THIS AREA. DO NOT HAVE THE CONFIDENCE TO GO DRY JUST YET...SO WILL LAYER POPS FROM 20 PERCENT FAR NW TO 50 PERCENT SE. THIS WILL ALLOW DAY SHIFT TO FINE TUNE FCST. HIGHS TODAY WILL RANGE FROM AROUND 80 ALONG THE LAKE MICHIGAN SHORELINE TO THE UPPER 80S ACRS THE SOUTH AND SOUTHEAST. FOR TONIGHT...FIRST COLD FRONT WILL SLOWLY SAG SOUTH. ANOTHER COLD FRONT WILL APCH THE REGION FROM THE NORTHWEST...MOVING INTO THE FCST AREA AFTER 06Z...AND THEN INTO THE SRN CWFA BY FRIDAY MORNING. SHOWERS AND THUNDERSTORMS SHOULD STILL BE ONGOING ALONG AND AHEAD OF THE FIRST COLD FRONT THIS EVENING...WHILE NOT MUCH IS EXPECTED IN THE WAY OF PCPN AHEAD OF THE NEXT FRONT. WILL LAYER POPS FROM 20 PERCENT NORTH TO 50 SOUTH FOR THE EVENING HOURS...THEN JUST A 30 PERCENT CHC IN THE FAR SOUTH AFTER MIDNIGHT. DRIER AIR WILL SLOWLY FILTER INTO THE REGION. LOWS TONIGHT WILL RANGE FROM THE LOWER TO MID 60S. LONG TERM... THE CURRENT FORECAST FOR THE FRIDAY THROUGH NEXT WEDNESDAY TIME FRAME IS A DRY ONE...EXCEPT FOR THE SOUTHERN PART OF THE CWA FRIDAY MORNING. THE GFS IS CONTINUING TO BE THE WETTEST MODEL FOR FRIDAY AND OVER THE LAST FEW RUNS IT HAS KEPT THE MAIN PART OF THE RAIN TO THE SOUTH. THE GFS IS JUST CREEPING SOME QPF INTO THE SOUTHERN PART OF OUR CWA. GFS/NAM SOUNDINGS ARE SHOWING FAIRLY DEEP MOISTURE YET FOR THE SOUTHERN PART OF THE CWA FRIDAY MORNING. SO WITH A CHANCE THAT SOME LINGERING SHOWERS/STORMS COULD BE GOING ON INTO FRIDAY MORNING...HAVE PUT IN A SMALL CHANCE FOR THE SOUTHERN PART OF THE CWA WHICH COLLABORATES WELL WITH NEIGHBORING OFFICES AS WELL. SURFACE HIGH PRESSURE THEN OVER THE AREA THROUGH NEXT WEDNESDAY. THE GFS IS SHOWING A FRONT TO MOVE THROUGH MICHIGAN AND CANADA TO THE NORTH NEXT TUESDAY AND TUESDAY NIGHT...BUT FOR RIGHT NOW TO HAVE NO AFFECT ON THE CWA. THE ONLY OTHER ITEM TO NOTE IS AN UPPER LEVEL SHORTWAVE THAT GFS IS SHOWING TO MOVE THROUGH SUNDAY NIGHT THROUGH TUESDAY NIGHT. THIS SHORTWAVE HAS BEEN SHOWN TO BE DRY FOR OUR CWA...SO LEFT THIS TIME FRAME DRY. WITH NO MAJOR CHANGES IN THE PATTERN FOR THIS COMING WEEK...850MB TEMPERATURES FOR EACH AFTERNOON ARE ROUGHLY SIMILAR. SO NO BIG RANGES IN MAX TEMPERATURES FOR FRIDAY THROUGH WEDNESDAY...FORECASTED TO BE FAIRLY SIMILAR FROM DAY TO DAY. && .AVIATION... A COLD FRONT WAS LOCATED FROM WRN LAKE SUPERIOR...SOUTHWEST INTO SE WISCONSIN...THEN INTO ERN IOWA AT 05Z. THIS FRONT WILL MOVE ACRS THE TAF SITES OVER THE NEXT 12 HOURS. SATELLITE IMAGERY THIS MORNING WAS SHOWING LOW LVL AC/STRATOCUMULUS ACRS NRN INDIANA. THESE CLOUDS WERE BEING SUSTAINED BY A MOIST LOW LVL WAA FLOW PATTERN. SOME ISOLATED SHOWERS/THUNDERSTORMS WERE LOCATED EAST OF KFWA...AND THESE SHOULD STAY EAST OF KFWA THROUGH THE NIGHT. THE AIRMASS WILL REMAIN UNSTABLE OUT AHEAD OF AFOREMENTIONED FRONT TODAY. HOWEVER...LATEST MODEL RUNS INDICATE THAT THE FRONT WILL BE SOUTHEAST OF KSBN BY 16Z. THUS...HAVE REMOVED CHC/S OF THUNDERSTORMS HERE AS IT LOOKS TO BE A SLIM CHC ATTM. AS FOR KFWA...FRONT WILL PASS THROUGH NEAR 22Z...SO HAVE MAINTAINED A VCTS IN THE TAF. FOR THURSDAY EVENING...ONLY SOME MID AND HIGH LVL CLOUDINESS WILL REMAIN ACRS THE REGION AS THE COLD FRONT SAGS SOUTH OF THE REGION. ANOTHER COLD FRONT WILL APCH THE FCST AREA FROM THE NORTH AFTER 06Z FRIDAY. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ SHORT TERM/AVIATION...HICKMAN LONG TERM...BML in AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE QUAD CITIES IA IL 446 PM CDT THU JUN 22 2006 .DISCUSSION... WILL UPDATE GOING FCST SHORTLY FOR PRECIP AND POPS IN THE SRN CWA. SHORTWV TRACKING E THRU IA/MO HAS FLARED UP AN AREA OF PRECIP NR IA/MO BORDER MORE WIDEPREAD THAN INITIALLY THOUGHT. BASED ON SATELLITE TRENDS AND THE RUC I EXPECT THIS PRECIP TO CONTINUE THROUGH EARLY TO MID EVENING BEFORE PUSHING SE. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ 50 ia AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE QUAD CITIES IA IL 1120 AM CDT THU JUN 22 2006 .UPDATE... MORNING MCS HAS EXITED THE CWA THIS MORNING... WITH LINE OF THUNDERSTORMS MOVING ACROSS NORTHERN MO LIKELY TO MISS THE CWA TO THE SOUTH. 15Z OBS INDICATE SURFACE STATIONARY FRONT DRAPED ACROSS CENTRAL MO/IL... THOUGH CONVECTION IN IL IS MUDDYING THE SFC ANALYSIS. DISTINCT MCV WAS OVER NE KS/NW MO... AND 12Z SUBJECTIVE UPPER AIR ANALYSIS INDICATED DEEP SHORTWAVE OVER NE KS. THESE FEATURES WILL PULL EASTWARD THROUGH THE DAY AND WILL HELP FUEL STORMS AHEAD OF THE WAVE ASSOCIATED WITH THE FRONT/MCV. QUESTION FOR CWA IS WHETHER STORMS WILL PUSH NORTHWARD INTO THE SOUTHERN COUNTIES. RUC PROGS INDICATE VIRTUALLY NO CAPE NORTH OF HWY 34... EVEN ELEVATED... AND ONLY MINIMAL THERE... THOUGH RUC SOUNDINGS DO INDICATE SOME SBCAPE AROUND 18Z IF TEMPS CAN MAKE IT INTO THE LOW-MID 80S. STORMS SHOULD MOVE MAINLY EASTWARD... WITH RIGHT-MOVERS MOVING ESE. BELIEVE CHANCE EXISTS FOR STORMS TO CLIP THE FAR SOUTHERN COUNTIES... BUT AREA WILL BE TOO FAR NORTH OF THE BOUNDARY WITH TOO LITTLE CAPE AND SHEAR TO SUSTAIN SEVERE STORMS THIS FAR NORTH. DESTABILIZATION IN CLEARING AREA SHOULD NOT BE ENOUGH TO OVERCOME DRYING AT LOW/MID LEVELS ENOUGH FOR STRONG UPDRAFTS... THOUGH MAY SEE PULSY STORMS THIS AFTERNOON IN AREAS OF STRONGEST HEATING... AND EXPECT SHOWERS AND SOME THUNDER MAY REACH INTO SOUTHERN AS MCV AND SHORTWAVE PASS BY. HAVE UPDATED FORECAST TO MAINTAIN LIKELY TO OCCASIONAL POPS SOUTH BUT TIGHTENED THE GRADIENT TO NO PRECIP IN THE NORTHERN 2/3 AS BELIEVE AREA IS TOO FAR POST-FRONTAL FOR THUNDERSTORMS TODAY. HAVE TWEAKED CLOUD AND TEMP GRIDS... BUT OTHER THAN CHANGES TO WEATHER AND POPS... CHANGES WERE MINOR. ..MAYES.. && .PREVIOUS DISCUSSION...ISSUED AT 400 AM... LATEST SFC/MSAS ANALYSIS WAS INDICATING INITIAL SFC BOUNDARY WASHING OUT ALONG THE MO/IA BORDER...AND UP THRU NORTHEAST IL AND WI. MORE DEFINED BOUNDARY TO THE NORTHWEST ACRS CENTRAL IA AND WESTERN WI GATEWAY TO DRIER AIRMASS. ANOTHER CONVECTIVELY ENHANCED VORT WILL ROLL ALONG SOUTHERN FRINGE OF WESTERLIES AND MAKE IT RIGHT ACRS THE SOUTH HALF OF THE LOCAL FA THRU MIDDAY...WITH ASSOCIATED MCS JUST UPSTREAM IMPACTING THE SAME AREA THIS MORNING. WILL COVER THE SOUTH HALF WITH CATEGORICAL AND LIKELY POPS...BUT WILL KEEP CHC POPS TO THE NORTH FOR MORE SCTRD AND ELEVATED TYPE CONVECTION. SOUTHERN 2-3 TIERS OF COUNTIES MAY BE SUSPECT TO ISOLATED SVR IN WAY OF WET MICROBURSTS UP TO 65 MPH...AND TO A LESSER EXTENT HAIL UP TO AN INCH. H25 MB JET STREAK INCREASING TO AT LEAST 100 KTS JUST NORTH OF THE MN/IA BORDER WILL ALSO ADD SUPPORT THIS MORNING TO STORM ACTIVITY. BETTER THERMODYNAMIC...INSTABILITY...AND LLVL CONVERGENCE OF THTA-E FIELDS ALL MIGRATE SOUTH AND SOUTHEAST OF THE CWA AS THE DAY PROGRESSES...WITH THE SOUTHEAST HALF OF MO AND SOUTH HALF OF IL LOOKING PRIME FOR SVR CONVECTIVE COMPLEXES/IGNITED BY REMNANTS OF CURRENT MCS/. AS LARGE HUDSON BAY REGION UPPER LEVEL VORTEX TAKING HOLD...MAIN BELT OF UPPER WESTERLIES WILL GET SHUNTED SOUTH AND MORE CYCLONIC IN NATURE THROUGH FRIDAY. THIS COMBINED WITH SFC RIDGE BUILDING DOWN ACRS THE UPPER MS RVR VALLEY AND EVENTUALLY THE WESTERN GRT LKS WILL SHUNT MAIN BOUNDARIES AND HIGHER SFC DPT POOLS SOUTH OF THE CWA BY FRIDAY...AND WILL TREND FCST POPS TO DRY LATER TODAY AND TONIGHT FROM NORTH TO SOUTH. BETS POPS TONIGHT WILL BE ACRS THE FAR SOUTH FOR SLIGHTLY ELEVATED CONVECTION FEEDING ON NORTHERN FRINGE OF RE-INVIGORATED LLVL THTA-E ADVECTION/CONVERGENCE FIELDS ACRS MO. GRT LKS HIGH AND ASSOCIATED LK EFFECT NORTHEAST FETCH WILL DEEPEN ACRS THE CWA AS FRI PROGRESSES...MAKING FOR A DRIER/LOWER RH AND PLEASANT DAY TO END THE WEEK. WITH INSOLATION AND MIXING IN DEEPENING NORTHEAST FETCH...EXPECT WIDESPREAD UPPER 70S TO LOW 80S FOR FRI HIGHS. RIDGE OVERHEAD AND MAINLY CLEAR SKIES FRI NIGHT SHOULD SET UP IDEAL RADIATION COOLING...AND WITH DPTS CONTINUING TO DRY OUT A SEASONABLY COOL NIGHT IN THE 50S WILL BE IN STORE. QUICK LOOK AT LONGER RANGE SUGGEST TROUBLING NORTHWEST FLOW EVENT STILL LOOKS TO BE ON TAP FOR SUNDAY AND WILL LEAVE THE EARLIER INTRODUCED CHC POPS. ..12.. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ MAYES ia AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DODGE CITY KS 334 PM CDT THU JUN 22 2006 .DISCUSSION... DAYS 1-2... MAIN QUESTION THIS CYCLE WILL AGAIN BE CONVECTION. CONVECTION ALREADY BLOWING UP ALONG THE FRONT RANGE OUT INTO NORTHWEST KANSAS AND THAT WILL BE THE MAIN CHALLENGE FOR TONIGHT. NONE OF THE 12Z OR 15Z MODELS HAD FORECAST ANY OF THE HUGE CONVECTIVE CLUSTER NOW IN SOUTHWEST NEBRASKA, NORTHEAST COLORADO AND FAR NORTHWEST KANSAS WHICH IS GREATLY DISTRESSING. EVEN THE USUALLY GOOD FSL RUC13 AND RUC20 MISSED IT ENTIRELY. THE MUCH VAUNTED 12Z WRF IN PARTICULAR WAS HORRIBLE IN BOTH INITIALIZATION AND SUBSEQUENT FORECASTS THROUGH ABOUT 12 HOURS. THE 18Z WRF DID INITIALIZE THE CONVECTION BUT IMMEDIATELY LOST IT IN ITS FORECASTS. PER DISCUSSION WITH GLD WILL HOLD ON TILL THE LAST MINUTE IN HOPES WE CAN DEDUCE ANY TRENDS FROM IT THAT WILL HELP WITH THE FORECAST. GIVEN THE ABOVE FOR TONIGHT WILL PLAY WHAT THE MODELS DID FORECAST, NAMELY ANOTHER MCS OFF THE HIGH TERRAIN OF COLORADO MOVING EAST AND SOUTHEAST INTO KANSAS AND THE PANHANDLES ALONG THE SURFACE FRONT WHICH EXTENDS FROM AROUND COS TO BETWEEN EHA AND LBL AND SOUTH ACROSS THE EAST TX PANHANDLE. MUCAPES IN THAT AREA WILL BE IN THE NEIGHBORHOOD OF 2500 J/KG WITH SUFFICIENT LOWER LEVEL SHEAR ALONG THE BOUNDARY THAT STORMS MAY EVEN BE ABLE TO SPIN UP SOME ISOLATED TORNADOES. AGREE COMPLETELY WITH SPC WATCH 545 FOR MUCH OF SOUTHWEST KANSAS AND WOULD NOT BE SURPRISED TO SEE A LATER WATCH INTO THE PANHANDLES. HAVE ALSO GONE CATEGORICAL FOR PRECIP FROM DDC WEST WHERE THE BIGGEST THREAT FOR LARGE HAIL, DAMAGING WINDS EXISTS. THE BEST THREAT FOR TORNADOES SHOULD REMAIN NEAR THE SURFACE FRONT IN MY FAR SOUTHWEST COUNTIES. AFTER TONIGHT THE SYNOPTIC SCALE SETUP SUPPORTS A FEW MORE NIGHTS OF LARGE SCALE CONVECTIVE SYSTEMS FIRING OFF THE HIGH TERRAIN AND MOVING SOUTH TO SOUTHEAST ACROSS THE HIGH PLAINS REGION. HAVE LEFT SOME SMALLER POPS IN PLACE AGAIN FOR TOMORROW NIGHT AS ANOTHER SYSTEM DEVELOPS SOMEWHERE AND MOVES THROUGH THE CWA. GIVEN THE MODELS PERFORMANCE AND THEIR HUGE UNCERTAINTIES, HAVE KEPT POPS LOW WITH THIS FEATURE. FOR TEMPERATURES HAVE KEPT THINGS A BIT COOLER BOTH NIGHTS AND ALSO ON SATURDAY AS THE MOS SEEMS TO GET CARRIED AWAY WITH WARMING IN SPITE OF THE RAIN COOLED AIR REINFORCING THE POLAR FRONT TO OUR SOUTH EACH NIGHT. DAYS 3-7... LATE IN THE PERIOD CONFIDENCE REMAINS LOW AS MODELS CONTINUE TO STRUGGLE WITH THE WEST COAST/ERN PACIFIC LOW AND LOCATION OF OUR UPPER RIDGE AXIS AROUND THE CNTL CONUS. AM THEREFORE LEANING TOWARDS PERSISTENCE ON DAYS 6 AND 7. UNTIL THEN ANY WAVE EMBEDDED IN THE NW FLOW LATE THIS WEEKEND STILL HAS THE POTENTIAL TO PRODUCE SOME PCPN SOMEWHERE IN WRN KS. AT THIS TIME AM UNABLE TO NARROW DOWN TIMING OR LOCATION DOWN DUE TO HOW MODELS HANDLE THESE WEAKER WAVES EMBEDDED IN THE FLOW. THE CURRENT GRIDS SEEM TO HAVE A DECENT HANDLE WITH THIS SO WILL RETAIN SMALL POPS ACROSS ALL OF OUR CWA SAT NIGHT AND SUNDAY NIGHT. AFTER THIS MODELS CONTINUE TO SUPPORT A COOL AND DRYER PATTERN THROUGH MID WEEK. CURRENT GRIDS FOR HIGHS STILL LOOK ON TRACK SINCE SEE LITTLE REASON TO GO MUCH WARMER BASED ON PROGGED EC OR GFS 85H TEMPS. DID LOWER OUR OVERNIGHT LOWS A FEW DEGREES AS THE MEX GUIDANCE ACTUALLY NOT LOOKING TOO BAD THIS MORNING WITH LOWS IN THE 50S FOR MUCH OF THE AREA. && .PRELIMINARY POINT TEMPS/POPS... DDC 62 85 62 85 / 90 10 10 20 GCK 61 86 61 85 / 90 10 20 30 EHA 61 84 61 87 / 100 10 20 10 LBL 62 86 62 87 / 100 10 20 10 HYS 62 85 62 84 / 30 0 10 20 P28 63 85 63 86 / 30 10 10 10 && .DDC WATCHES/WARNINGS/ADVISORIES...SVR TSTM WATCH 545 TIL 11PM CDT. && $$ FN08/18 JOHNSON/BURGERT ks AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GOODLAND KS 230 PM MDT THU JUN 22 2006 .DISCUSSION...MAIN FORECAST PROBLEM WILL BE CHANCE OF PRECIPITATION THROUGH THE PERIOD. SATELLITE SHOWING A PROGRESSIVE FLOW FROM THE EASTERN PACIFIC INTO THE WESTERN ATLANTIC. HOWEVER...FLOW OVER THE CENTRAL PACIFIC HAS BEGUN TO AMPLIFY AND RETROGRESS. THIS WILL PROBABLY HERALD THE CHANGE TO THE AMPLIFIED PATTERN OVER THE COUNTRY THAT HAS BEEN PROGGED BY THE MODELS. THREE SHORTWAVES TO NOTE IN THE PROGRESSIVE FLOW. FIRST ONE IS MOVING IN FROM SOUTHEAST WYOMING AND WESTERN NEBRASKA. SECOND ONE WAS MOVING THROUGH THE PACIFIC NORTHWEST. THIRD ONE IS APPROACHING THE PACIFIC NORTHWEST. MAIN FRONTAL BOUNDARY STILL LIES TO THE SOUTH OF THE FORECAST AREA WITH THE DEEPER LOW LEVEL MOISTURE TRAPPED TO THE SOUTH OF IT. AT JET LEVEL...MODELS INITIALIZED FINE. AT MID LEVELS...SATELLITE SHOW THE MODELS NOT TOO BAD. UKMET/GFS WERE CATCHING THE SHORTWAVE DETAILS IN THE PACIFIC THE BEST WITH THE GFS DOING SLIGHTLY BETTER ON THE LOW POSITIONS. HOWEVER...THE UKMET AND RUC LOOK TO BE CAPTURING THE SECOND AND THIRD SHORTWAVE POSITIONS THE BEST. ALSO THE RUC AND UKMET ARE CATCHING THE SOUTHEAST WYOMING SHORTWAVE THE BEST. HOWEVER...THE UKMET DAMPENS THIS SHORTWAVE OUT. MODELS HAVE TROUBLE WITH TROUGH POSITIONS AND STRENGTH OVER THE WESTERN AND CENTRAL PORTIONS OF THE COUNTRY. THE MODELS WERE TOO FAR EAST/NOT DEEP ENOUGH WITH SYSTEMS. THIS WAS ESPECIALLY TRUE OF THE EXITING SYSTEM TO OUR EAST THAT BROUGHT THE OVERNIGHT CONVECTION. THE GFS WAS THE CLOSEST BUT IT WAS TOO FAR EAST. THE PROBLEMS WERE NOT AS BAD OUT WEST. WITH THE EXCEPTION OF THE EXITING SYSTEM...THE UKMET WAS DOING SLIGHTLY BETTER ON THE HEIGHT FIELD OVER THE GFS. AT LOW LEVELS...MODELS DOING VERY WELL WITH CURRENT SITUATION. NAM IS DOING THE BEST RIGHT NOW ON THE WIND FIELD. GFS INITIALIZED A LITTLE BETTER THAN THE REST ON TEMPERATURES. WILL GO WITH A BLEND OF THE GFS/UKMET/NAM FOR THIS FORECAST. TONIGHT...INTERESTING COMPLICATED FORECAST FOR TONIGHT. THUNDERSTORMS HAVE BEEN ONGOING/APPROACHING FROM THE NORTHWEST ALL DAY. THIS IS IN RESPONSE TO THE WYOMING SHORTWAVE. ALSO...EITHER ANOTHER FRONTAL SURGE ASSOCIATED WITH THE SHORTWAVE...OUTFLOW BOUNDARY...OR BOTH PROVIDING SURFACE CONVERGENCE HELP TO THE INCOMING SHORTWAVE. RIGHT REAR QUADRANT OF THE JET IS OVER THE SOUTHERN AREAS EARLY ON. THE PRECIPITATION FORECAST WILL HINGE ON THE TRENDS OF THIS CONVECTION. HOWEVER...BASED ON CURRENT TRENDS IT LOOKS LIKE CONVECTION MAY HAVE PUSHED THROUGH MOST OF THE WESTERN PORTION OF THE FORECAST AREA WITH THE EASTERN PORTION RECEIVING THE BRUNT OF THIS. PRECIPITATION SHOULD SHUT OFF QUICKLY WITH DRY AIR AT MID LEVELS COMING IN BEHIND THIS FEATURE. FRIDAY/FRIDAY NIGHT...SHOULD BE SEEING SHORTWAVE RIDGING AND SUBSIDENCE THROUGH MOST OF THE DAY BEFORE NEXT SHORTWAVE TROUGH MOVES IN FROM THE NORTHWEST. NAM/NGM SHOW A RIGHT REAR QUADRANT OF THE JET MOVING ACROSS DURING THE AFTERNOON. THE GFS/UKMET DO NOT SHOW THIS. WINDS SHIFT AROUND TO THE SOUTH EARLY...AND RAPIDLY INCREASE THE LOW LEVEL MOISTURE...ESPECIALLY OVER THE WESTERN HALF OF THE FORECAST AREA. WILL KEEP SLIGHT CHANCE TO CHANCE OVER THE AREA... ESPECIALLY AT NIGHT. WILL TEND TO GO NEAR TO SLIGHTLY BELOW GUIDANCE. SATURDAY/SATURDAY NIGHT...ANOTHER SHORTWAVE MOVES INTO THE AREA. THIS ONE HAS A SURFACE BOUNDARY ASSOCIATED WITH IT. AFTER IGNORING IT YESTERDAY...MODEL GUIDANCE APPEARS TO HAVE CAUGHT ON TO THIS FEATURE...AND THE POPS HAVE INCREASED. ALSO SURFACE BOUNDARY PUSHES INTO THE NORTHERN AND WESTERN PORTIONS OF THE FORECAST AREA IN THE AFTERNOON...AND THROUGH THE AREA DURING THE EVENING. WILL START THE CHANCE IN THE AFTERNOON...HIGHEST IN THE WEST...AND THEN PUSH IT ACROSS THE AREA. WILL GO WARMEST IN THE SOUTH AHEAD OF THE BOUNDARY. SUNDAY/SUNDAY NIGHT...AT THE SURFACE...POST FRONTAL UPSLOPE WILL KEEP MOISTURE IN PLACE WITH ANOTHER SHORTWAVE COMING THROUGH IN NORTHWEST FLOW ALOFT. WILL AGAIN GO CHANCE STARTING IN THE LATE AFTERNOON. WILL TEND TO GO NEAR TO SLIGHTLY BELOW GUIDANCE DUE TO WET GROUND AND UPSLOPE WINDS. FOR MONDAY THROUGH THURSDAY...MODELS HAVE CONTINUED THEIR GOOD PERFORMANCE AND PREVIOUS TRENDS. IN GENERAL...MODELS ARE MAKING THE WESTERN RIDGE MORE AMPLIFIED AND FURTHER WEST WITH THE RIDGE AXIS. THIS LOOKS REASONABLE CONSIDERING HOW THE FLOW IS TRANSITIONING RIGHT NOW. OVERALL THE GFS DOES THE BEST WITH THIS SCENARIO WITH THE ECMWF NOT TOO FAR BEHIND UNTIL THE END OF THE PERIOD. THE ECMWF BREAKS DOWN THE RIDGE TOO FAST AND IS TOO PROGRESSIVE AT THIS TIME. ALMOST STRAIGHT NORTH FLOW ALOFT THEN WE START TRANSITIONING INTO A MORE NORTHWEST FLOW ALOFT IN THE TUESDAY TO THURSDAY TIME FRAME. AGAIN HARD TO SAY WHAT WILL HAPPEN IN THIS PATTER WITH THE DETAILS ALMOST IMPOSSIBLE TO PREDICT ON THE PRECIPITATION. WILL KEEP SOME KIND OF SLIGHT CHANCE OR LOW CHANCE POPS IN FOR MOST OF THE PERIOD. TEMPERATURES IN THIS FLOW ALOFT WILL NOT WARM TOO MUCH...AND GUIDANCE LOOKS REASONABLE AND WILL PROBABLY GO CLOSE TO. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. NE...NONE. CO...NONE. && $$ BULLER ks AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WICHITA KS 1204 PM CDT THU JUN 22 2006 .UPDATE... THIS AFTERNOON: NEARLY ALL FACETS OF INHERITED FORECAST APPEAR INTACT...AS BEST CHANCES FOR TSRA REMAIN SLATED FOR SE KS WHERE NO DOUBT CLOSER TO 850-MB COLD FRONT THAT'LL SURGE SE ACROSS THE REGION INTO MOISTURE- RICH ENVIRONMENT. PER LATEST IR IMAGERY AC & CUMULIFORM DEBRIS DISSIPATING RAPIDLY & WITH SFC & 850-MB DEWPOINTS OF ~65F & ~15C RESPECTIVELY AIRMASS SHOULD QUICKLY DESTABILIZE WITH SBCAPES REACHING 2000-2500 J/KG...SO A FEW SVR TSRA POSSIBLE. ONLY CHANGE TO FORECAST WAS TO "UPGRADE" THE WX DESCRIPTOR FROM "TRW-" TO "TRWM"...ESPECIALLY OVER SE KS. && .PREV DISCUSSION... /ISSUED 535 AM CDT THU JUN 22 2006/ UPDATE... WILL UPDATE TO LOWER PRECIP CHANCES THROUGH 18Z TO BETTER REPRESENT CURRENT TRENDS. PRECIP HAS REALLY DECREASED OVER THE ENTIRE AREA OVER THE LAST COUPLE OF HOURS. HOWEVER BOTH THE 09Z RUC AND 06Z WRF/NAM ARE CONTINUING TO REDEVELOP ACTIVITY FROM NEAR SLN TO ICT BETWEEN 12Z AND 15Z. NOTICED THAT THE RUC ANALYSIS IS STILL SHOWING AROUND 1500J/KG OF MU CAPE ALONG AND EAST OF I 135 ALONG WITH SOME WEAK 700MB WARM ADVECTION AND UPGLIDE ALONG THE 310K SURFACE. THEREFORE AM HESITANT TO YANK POPS OVER CENTRAL KS...BUT DID LOWER QUITE A BIT FROM ORIGINAL ZONE ISSUANCE. LAWSON && PREV DISCUSSION... /ISSUED 318 AM CDT THU JUN 22 2006/ DISCUSSION... MAIN FORECAST CONCERN WILL BE STRENGTH OF CONVECTIVE ACTIVITY TODAY AND THEN PRECIP CHANCES TONIGHT THROUGH SAT NIGHT. TODAY-TONIGHT: LARGE AREA OF SHOWERS AND STORMS IS CURRENTLY AFFECTING A GOOD PORTION OF FORECAST AREA AS I TYPE. LARGE AREA OF STORMS OVER WESTERN KS EARLIER THIS EVENING GENERATED AN MCV THAT IS CURRENTLY SITUATED NEAR GBD AND WILL TRACK EAST ACROSS FORECAST AREA TODAY. 850MB FRONT WILL BE LINGERING AROUND THIS AREA PROVIDING SOME ADDITIONAL FOCUS FOR STORMS. SEVERE POTENTIAL TODAY WILL BE HIGHLY PREDICATED ON AMOUNT OF INSTABILITY OVER SE KS THIS AFTERNOON. FEEL STORM INITIATION WOULD BE LIKELY DOWN THERE IF SOME SUN WOULD BE POSSIBLE. IF TEMPS CAN GET TO AROUND 80 IN SE KS...THERE WOULD BE AROUND 2500-3000J/KG OF CAPE...WITH A GOOD PORTION OF BELOW 700MB. DAY SHIFT WILL HAVE TO MONITOR AREA CLOSELY THIS AFTERNOON. AREAL COVERAGE OF PRECIP SHOULD DECREASE FROM WEST TO EAST AS THE DAY PROGRESSES SO ADJUST POPS IN GRIDS ACCORDINGLY. EVEN IF WE GET SOME SUN TODAY...SATURATED GROUNDS WILL NOT ALLOW TO MUCH OF A WARM UP...SO WENT WITH HIGHS A TAD BELOW GFS MOS. FOR TONIGHT IT APPEARS THERE WILL BE A COUPLE REGIONS FOR STORM DEVELOPMENT. THE FIRST WILL BE SW KS/SE CO WHERE UPSLOPE WILL BE VERY PREVALENT TODAY. THE SECOND WOULD BE OVER EXTREME SE KS/NORTHERN AR AND SOUTHERN MO ALONG FRONT AS LOW LEVEL JET PICKS UP. THEREFORE WILL KEEP HIGHEST RAIN CHANCES OVER SE KS. FRI-SAT: BY FRI MORNING THERE SHOULD BE STORMS OVER ONGOING OVER WESTERN OK AND THE OZARKS. WILL KEEP A SLIGHT CHANCE FOR PRECIP FOR SOUTHERN PORTION OF FORECAST AREA WITH THE THINKING THAT STORMS OVER SW KS MAY GENERATE ANOTHER...WEAKER...MCV. HOWEVER...CONFIDENCE IS LOW ON THIS PANNING OUT. IT APPEARS THE MOST LIKELY AREA FOR STORM DEVELOPMENT DURING THE AFTERNOON ON BOTH FRI AND SAT WOULD BE OVER THE HIGH PLAINS OF NE/WY AS MOISTURE RETURNS AROUND THE WESTERN PERIPHERY OF SURFACE HIGH. WITH THE POSITION OF THE UPPER RIDGE WILL TO OUR WEST...WEAK DIFFLUENCE ALOFT WILL SET UP. IT WILL BE INTERESTING TO SEE IF STORMS THAT DEVELOP OVER THE NORTHERN HIGH PLAINS CAN MAKE IT THIS FAR SOUTH. SO WILL KEEP SLIGHT CHANCES FOR STORMS IN FOR FRI NIGHT OVER CENTRAL KS AND GO SLIGHTS EVERYWHERE FOR SAT NIGHT AS STORM INITIATION MAY TAKE PLACE CLOSER TO HOME...IE NW KS. WITH SATURATED GROUNDS STILL IN PLACE...MUCH OF HEATING WILL GO TOWARDS EVAPORATION...THUS KEEPING HIGHS IN CHECK. SO WILL GO UNDER GUIDANCE A FEW DEGREES FOR BOTH OF THESE DAYS. SUN-WED: BOTH ECM AND GFS ARE FORECASTING A FAIRLY POTENT UPPER WAVE TO TRACK FROM WI AND INTO THE MISSOURI VALLEY DURING THE DAY SUN. EVEN WITH WEAK COLD FRONT SOUTH OF AREA...THIS FEATURE MAY PROVIDE ENOUGH LIFT OVER THE EASTERN PORTION OF FORECAST AREA TO GET PRECIP FOR SUN. WITH THIS WAVE TRACKING INTO THE OHIO VALLEY BY MON...WILL SHUT PRECIP CHANCES AFTER SUN...EXPECTING SUBSIDENCE BEHIND THIS WAVE. NW FLOW WILL REMAIN IN PLACE MON-WED KEEPING TEMPS CLOSE TO NORMAL WITH NO SIGNIFICANT WARM-UPS ANTICIPATED. LAWSON && PRELIMINARY POINT TEMPS/POPS... WICHITA-KICT 84 64 85 64 / 60 20 20 10 HUTCHINSON 84 63 86 64 / 60 20 10 10 NEWTON 84 64 85 64 / 70 30 20 10 ELDORADO 85 64 84 64 / 70 40 20 10 WINFIELD-KWLD 86 65 85 65 / 60 30 20 10 RUSSELL 82 62 87 63 / 40 20 10 20 GREAT BEND 83 62 87 63 / 40 20 10 20 SALINA 84 63 85 63 / 70 30 10 20 MCPHERSON 84 63 85 63 / 60 20 10 20 COFFEYVILLE 86 65 83 64 / 80 60 30 10 CHANUTE 84 65 84 62 / 90 70 20 10 IOLA 84 65 83 62 / 90 70 20 10 PARSONS-KPPF 85 65 83 64 / 80 60 20 10 && .ICT WATCHES/WARNINGS/ADVISORIES... NONE. && $$ ks AREA FORECAST DISCUSSION...UPDATE NATIONAL WEATHER SERVICE WICHITA KS 535 AM CDT THU JUN 22 2006 .UPDATE... WILL UPDATE TO LOWER PRECIP CHANCES THROUGH 18Z TO BETTER REPRESENT CURRENT TRENDS. PRECIP HAS REALLY DECREASED OVER THE ENTIRE AREA OVER THE LAST COUPLE OF HOURS. HOWEVER BOTH THE 09Z RUC AND 06Z WRF/NAM ARE CONTINUING TO REDEVELOP ACTIVITY FROM NEAR SLN TO ICT BETWEEN 12Z AND 15Z. NOTICED THAT THE RUC ANALYSIS IS STILL SHOWING AROUND 1500J/KG OF MU CAPE ALONG AND EAST OF I 135 ALONG WITH SOME WEAK 700MB WARM ADVECTION AND UPGLIDE ALONG THE 310K SURFACE. THEREFORE AM HESITANT TO YANK POPS OVER CENTRAL KS...BUT DID LOWER QUITE A BIT FROM ORIGINAL ZONE ISSUANCE. LAWSON && .PREV DISCUSSION... /ISSUED 318 AM CDT THU JUN 22 2006/ DISCUSSION... MAIN FORECAST CONCERN WILL BE STRENGTH OF CONVECTIVE ACTIVITY TODAY AND THEN PRECIP CHANCES TONIGHT THROUGH SAT NIGHT. TODAY-TONIGHT: LARGE AREA OF SHOWERS AND STORMS IS CURRENTLY AFFECTING A GOOD PORTION OF FORECAST AREA AS I TYPE. LARGE AREA OF STORMS OVER WESTERN KS EARLIER THIS EVENING GENERATED AN MCV THAT IS CURRENTLY SITUATED NEAR GBD AND WILL TRACK EAST ACROSS FORECAST AREA TODAY. 850MB FRONT WILL BE LINGERING AROUND THIS AREA PROVIDING SOME ADDITIONAL FOCUS FOR STORMS. SEVERE POTENTIAL TODAY WILL BE HIGHLY PREDICATED ON AMOUNT OF INSTABILITY OVER SE KS THIS AFTERNOON. FEEL STORM INITIATION WOULD BE LIKELY DOWN THERE IF SOME SUN WOULD BE POSSIBLE. IF TEMPS CAN GET TO AROUND 80 IN SE KS...THERE WOULD BE AROUND 2500-3000J/KG OF CAPE...WITH A GOOD PORTION OF BELOW 700MB. DAY SHIFT WILL HAVE TO MONITOR AREA CLOSELY THIS AFTERNOON. AREAL COVERAGE OF PRECIP SHOULD DECREASE FROM WEST TO EAST AS THE DAY PROGRESSES SO ADJUST POPS IN GRIDS ACCORDINGLY. EVEN IF WE GET SOME SUN TODAY...SATURATED GROUNDS WILL NOT ALLOW TO MUCH OF A WARM UP...SO WENT WITH HIGHS A TAD BELOW GFS MOS. FOR TONIGHT IT APPEARS THERE WILL BE A COUPLE REGIONS FOR STORM DEVELOPMENT. THE FIRST WILL BE SW KS/SE CO WHERE UPSLOPE WILL BE VERY PREVALENT TODAY. THE SECOND WOULD BE OVER EXTREME SE KS/NORTHERN AR AND SOUTHERN MO ALONG FRONT AS LOW LEVEL JET PICKS UP. THEREFORE WILL KEEP HIGHEST RAIN CHANCES OVER SE KS. FRI-SAT: BY FRI MORNING THERE SHOULD BE STORMS OVER ONGOING OVER WESTERN OK AND THE OZARKS. WILL KEEP A SLIGHT CHANCE FOR PRECIP FOR SOUTHERN PORTION OF FORECAST AREA WITH THE THINKING THAT STORMS OVER SW KS MAY GENERATE ANOTHER...WEAKER...MCV. HOWEVER...CONFIDENCE IS LOW ON THIS PANNING OUT. IT APPEARS THE MOST LIKELY AREA FOR STORM DEVELOPMENT DURING THE AFTERNOON ON BOTH FRI AND SAT WOULD BE OVER THE HIGH PLAINS OF NE/WY AS MOISTURE RETURNS AROUND THE WESTERN PERIPHERY OF SURFACE HIGH. WITH THE POSITION OF THE UPPER RIDGE WILL TO OUR WEST...WEAK DIFFLUENCE ALOFT WILL SET UP. IT WILL BE INTERESTING TO SEE IF STORMS THAT DEVELOP OVER THE NORTHERN HIGH PLAINS CAN MAKE IT THIS FAR SOUTH. SO WILL KEEP SLIGHT CHANCES FOR STORMS IN FOR FRI NIGHT OVER CENTRAL KS AND GO SLIGHTS EVERYWHERE FOR SAT NIGHT AS STORM INITIATION MAY TAKE PLACE CLOSER TO HOME...IE NW KS. WITH SATURATED GROUNDS STILL IN PLACE...MUCH OF HEATING WILL GO TOWARDS EVAPORATION...THUS KEEPING HIGHS IN CHECK. SO WILL GO UNDER GUIDANCE A FEW DEGREES FOR BOTH OF THESE DAYS. SUN-WED: BOTH ECM AND GFS ARE FORECASTING A FAIRLY POTENT UPPER WAVE TO TRACK FROM WI AND INTO THE MISSOURI VALLEY DURING THE DAY SUN. EVEN WITH WEAK COLD FRONT SOUTH OF AREA...THIS FEATURE MAY PROVIDE ENOUGH LIFT OVER THE EASTERN PORTION OF FORECAST AREA TO GET PRECIP FOR SUN. WITH THIS WAVE TRACKING INTO THE OHIO VALLEY BY MON...WILL SHUT PRECIP CHANCES AFTER SUN...EXPECTING SUBSIDENCE BEHIND THIS WAVE. NW FLOW WILL REMAIN IN PLACE MON-WED KEEPING TEMPS CLOSE TO NORMAL WITH NO SIGNIFICANT WARM-UPS ANTICIPATED. LAWSON && PRELIMINARY POINT TEMPS/POPS... WICHITA-KICT 84 64 85 64 / 60 20 20 10 HUTCHINSON 84 63 86 64 / 60 20 10 10 NEWTON 84 64 85 64 / 70 30 20 10 ELDORADO 85 64 84 64 / 70 40 20 10 WINFIELD-KWLD 86 65 85 65 / 60 30 20 10 RUSSELL 82 62 87 63 / 40 20 10 20 GREAT BEND 83 62 87 63 / 40 20 10 20 SALINA 84 63 85 63 / 70 30 10 20 MCPHERSON 84 63 85 63 / 60 20 10 20 COFFEYVILLE 86 65 83 64 / 80 60 30 10 CHANUTE 84 65 84 62 / 90 70 20 10 IOLA 84 65 83 62 / 90 70 20 10 PARSONS-KPPF 85 65 83 64 / 80 60 20 10 && .ICT WATCHES/WARNINGS/ADVISORIES... NONE. && $$ ks AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 357 PM EDT THU JUN 22 2006 .DISCUSSION... MAIN FCST CONCERNS ARE TEMPS TONIGHT AND THEN WHEN TO INTRODUCE PCPN CHANCES INTO FCST FRI-SUN. WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW WRLY FLOW UNDERCUTTING A RIDGE OVER THE CANADIAN ROCKIES. DOWNSTREAM OF THE RIDGE...A TROF HAS AMPLIFIED FROM HUDSON BAY INTO THE UPPER LAKES AS A SHORTWAVE TRACKED THRU ONTARIO. COLD FRONT ASSOCIATED WITH THE SHORTWAVE HAS CLEARED THE FCST AREA (JUST RECENTLY KMNM) AND IS INTRODUCING A COOL/DRY AIRMASS INTO UPPER MI. 12Z RAOBS SHOWED 850MB TEMPS OF 3/0C AT KINL/CWPL WHICH ARE 8/10C LWR THAN THE 00Z READINGS. PRECIPITABLE WATER FROM BOTH SOUNDINGS WAS LOW AT AROUND 0.35 INCHES...WHICH IN THE CASE OF KINL IS 43PCT OF NORMAL. STRATUS/STRATOCU IN THE WAKE OF THE FRONT ARE ERODING FROM THE NW...AND IN FACT SKIES HAVE BEEN CLEAR OVER THE KEWEENAW SINCE ABOUT 18Z. A CHILLY NIGHT IS EXPECTED TONIGHT AS HIGH PRES SETTLES OVER UPPER MI. SKIES WILL BECOME CLEAR/MOSTLY CLEAR EARLY WHERE CLOUDS HAVE NOT CLEARED OUT YET. HOWEVER...THERE IS A BATCH OF CLOUDS TO THE NW AROUND KINL THAT ARE NOT GENERATED BY DAYTIME HEATING. CANADIAN RADARS EVEN SHOW ISOLD -SHRA/SPRINKLES WITHIN THE CLOUD AREA. SPRINKLES WON'T SURVIVE THIS FAR E INTO THE DRY AIR...BUT SCT MID CLOUDS MAY DRIFT ACROSS THE AREA LATE EVENING/OVERNIGHT. WILL NOT PLAN ON THE CLOUDS REALLY AFFECTING COOLING TONIGHT (EVENING SHIFT WILL NEED TO WATCH TRENDS TO SEE IF CLOUDS MAY BE A FACTOR TO KEEP TEMPS UP). WITH LIGHT/CALM WIND...MOSTLY CLEAR SKIES AND LOW PRECIPITABLE WATER (DEPICTED BY 12Z KINL/CWPL SOUNDINGS TO ENHANCE RADIATIONAL COOLING)...TEMPS SHOULD PLUMMET. GOING FCST HAS THIS COVERED WELL WITH MINS GENERALLY IN THE LOW 40S ACROSS THE FCST AREA AND AS LOW AS THE UPPER 30S IN THE TYPICAL COLD SPOTS. PROBABLY WON'T QUITE BE COLD ENOUGH TO SEE ANY FROST. 38F RECORD FOR THE 23RD AT THE OFFICE IS WITHIN REACH. HIGH PRES JUST DRIFTS TO THE SE FRI. UNDER PARTLY TO MOSTLY SUNNY SKIES (MORE CLOUDS SW WHERE WEAK ISENTROPIC ASCENT IS INDICATED)... MIXING UPWARDS OF 750MB ON NAM/GFS FCST SOUNDINGS YIELDS MAX TEMPS AS HIGH AS 75F AT THE TOP END WHICH IS INLINE WITH MOS GUIDANCE. NAM INDICATES MLCAPE INCREASING TO 400-600J/KG OVER THE FAR W (VCNTY OF KIWD) LATE IN THE AFTN WHILE GFS SHOWS MLCAPE INCREASING TO 600-800J/KG. MODELS SEEM A BIT QUICK TO INCREASE THE BOUNDARY LAYER MOISTURE...SO DO NOT ANTICIPATE ANY LATE AFTN CONVECTION ESPECIALLY CONSIDERING LACK OF FORCING. WILL ALSO STAY WITH A DRY FCST SAT NIGHT DESPITE GFS CONTINUED INSISTENCE ON SOME PCPN ACROSS THE WRN FCST AREA. DEEP LAYER FORCING IS MEAGER AT BEST AS IS ISENTROPIC ASCENT/WAA/MOISTURE ADVECTION. IN ADDITION...WEAK SHORTWAVE ENERGY TRACKS ESE TO THE SW OF UPPER MI. A STRONGER SHORTWAVE IS INDICTED TO DROP INTO THE UPPER MISSISSIPPI VALLEY ON SAT AND INTO THE WRN LAKES ON SUN. THERE IS SOME DISAGREEMENT ON HOW FAR S THE SHORTWAVE WILL DIG WITH THE CANADIAN/UKMET FARTHER S THAN THE GFS/NAM. AT THIS TIME RANGE... DIFFERENCE DOESN'T REALLY IMPACT FCST HERE SIGNIFICANTLY AS ALL THE SOLUTIONS SUGGEST THE MORE SIGNIFICANT PCPN WOULD STAY S OF FCST AREA WHERE INSTABILITY/FORCING WILL BE GREATER. WILL BRING IN LOW CHC POPS SAT AFTN OVER THE SW/CNTRL AND SPREAD ACROSS THE REST OF THE FCST AREA BY SUN AFTN. MON THRU THU...THERE IS MORE DISAGREEMENT TODAY BTWN THE 00Z UKMET/ECMWF/CANADIAN/GFS FOR THIS PERIOD. CHANGE THAT BEGAN TO SHOW UP IN YESTERDAYS 12Z RUNS CONTINUES WITH MANY OF THE 00Z MODELS TODAY. ECWMF SHOWS GOOD CONSISTENCY WITH THE LAST 2 RUNS (12Z/21 AND 00Z/22). IT HAS THE SHORTWAVE THAT DROPS INTO THE WRN LAKES SUN BECOMING NEARLY STATIONARY AS A CLOSED MIDLEVEL LOW OVER THE MIDWEST MON-THU AS MAIN FLOW ABANDONS IT BY SHIFTING WELL TO THE N. AFTER THE GFS (12Z/21 RUN) SHOWED SOMETHING SIMILAR TO THE ECWMF YESTERDAY...THE RECENT GFS RUNS HAVE GONE BACK TO THE PATTERN IT HAD BEEN SHOWING FOR SOME TIME (NAMELY ANOTHER SHORTWAVE REESTABLISHING THE TROF FROM HUDSON BAY TO THE GREAT LAKES DURING THIS PERIOD). THE 00Z CANADIAN/UKMET LEND SUPPORT TO THE ECMWF WHILE THE GFS ENSEMBLES GENERALLY SUPPORT THE OPERATIONAL GFS. THE 12Z ECMWF/CANADIAN ARE TRENDING BACK TOWARD THE GFS SOLUTION WITH TROFFING FROM HUDSON BAY TO THE GREAT LAKES. SO...WILL FAVOR SOMETHING ALONG THE LINES OF THE GFS GIVEN ITS OVERALL CONSISTENCY ON THE LARGER SCALE PATTERN FOR THE LAST MANY RUNS AND SINCE IT STRONGLY SUPPORTS THE GOING FCST. SIMILAR TO THE DISCUSSION YESTERDAY...WILL MAINTAIN A DRY DAY MON... ASSUMING THE SHORTWAVE FROM SUN SLIPS FAR ENOUGH S AND E. NEXT SHORTWAVE AND WEAK COLD FRONT WILL PASS THRU THE AREA TUE...AND WILL THUS CONTINUE WITH LOW CHC POPS MON NIGHT/TUE. WILL LEAVE WED DRY AND EXTEND INTO THU WITH NO CONSISTENT INDICATIONS OF ANY SHORTWAVES APPROACHING THE AREA. AS FOR TEMPS...WNW/NW FLOW PATTERN SUGGESTS TYPICAL EARLY SUMMER CONDITIONS FOR UPPER MI WITH TEMPS CLOSE TO NORMAL THRU THE PERIOD. && .MQT...WATCHES/WARNINGS/ADVISORIES...NONE. && $$ ROLFSON mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAND RAPIDS MI 1150 AM EDT THU JUN 22 2006 .UPDATED... I UPDATED THE AFTERNOON FORECAST THE 30 PCT CHANCE FOR THUNDERSTORMS NORTH TO INTERSTATE 96. LOOKING RUC AND NAM SOUNDINGS OVER LAKE MICHIGAN AND IN VARIOUS PARTS OF SOUTHWEST LOWER MICHIGAN THERE IS AN ELEVATED INSTABILITY LAYER ABOVE 700 MB THAT THE MCV MOVING OUT OF EASTERN IOWA INTO WRN IL HAS ACTIVATED. AS THE LEAD EDGE OF THE MCS MOVED OVER LAKE MICHIGAN AROUND 9 AM...AN AREA OF CONVECTION DEVELOPED OUT AHEAD OF IT DEVELOPED AND IS NOW MOVING ON SHORE. SINCE THE FRONTAL BOUNDARY IS NEAR BY...FROM FNT TO GRR AT 14Z... THE MCV MAY ACT TO INDUCE A WAVE ON THE FRONT AND KEEP THE CONVECTION GOING EAST ACROSS THE CWA. I DO NOT EXPECT MUCH SURFACE BASED CONVECTION DUE TO THE LARGE AMOUNT OF MID AND HIGH CLOUDS FROM THE MCS EVEN SO I WOULD NOT RULE OUT AN ISOLATED SEVERE WEATHER REPORT NEAR AND SOUTH OF THE FRONT THIS AFTERNOON. TONIGHT...THE CANADIAN COLD FRONT MOVES SOUTH THROUGH THE CWA AND BOTH THE 06Z AND 12Z RUNS OF THE NAM HAVE CONVECTION WITH THAT BOUNDARY NORTH OF INTERSTATE 96. GIVE THE JET ENTRANCE REGION IS OVER CNTRL LOWER MICHIGAN TONIGHT AND THERE IS SOME MID LEVEL MOISTURE NORTH OF INTERSTATE 96 WITH SOME ELEVATED INSTABILITY... IT MADE SENSE TO ME SO I PUT A 30 PCT CHANCE OF THUNDERSTORM OVER OUR NORTHERN ZONES TONIGHT. .GRR WATCHES/WARNINGS/ADVISORIES...NONE. && $$ WDM mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN 328 PM CDT THU JUN 22 2006 .DISCUSSION...TONIGHT THROUGH SUNDAY COLD FRONT MOVING ACROSS SOUTHERN MN ATTM WITH DRIER LOW LEVEL AIR IN ITS WAKE. HIGH PRESSURE CURRENTLY ACROSS NORTHERN MN WILL SPREAD INTO WI BY DAYBREAK WITH LOWS NEAR 50 OVER THE EASTERN CWA. ALTHOUGH A WEAK SHORTWAVE IS PROGGED TO PASS ACROSS US THIS EVENING... KEPT THE FORECAST DRY AS THE FEW SHOWERS AND CLOUDS TO OUR NW HAVE BEEN SHRINKING AS THEY MOVE SOUTHEAST. BEST LAYER MOISTURE AND Q-VECTOR CONVERGENCE ARE PROGGED BY THE RUC TO PASS JUST NORTH OF THE CWA THIS EVENING. EVENING CREW CAN HANDLE A SHOWER OR TWO WITH A NOW. THE NEXT WEATHER MAKER WILL BE A DEEPENING SHORTWAVE DROPPING IN FROM THE NORTHWEST ON SATURDAY. THE NAM HAS THE BEST RUN TO RUN CONTINUITY WHILE THE GFS IS SHOWING A SOUTHWARD DISPLACEMENT WITH THE SHORTWAVE WITH EACH SUCCESSIVE RUN. AFTER SEEING THE 09Z SREF...SIDED MORE WITH THE NAM FOR FRIDAY NIGHT AND SATURDAY. RAISED POPS TO 50 PERCENT OVER WEST CENTRAL AREAS LATE FRIDAY NIGHT AND THEN SPREAD THE 50 POPS ACROSS CENTRAL AND EAST CENTRAL MN ON SATURDAY. STRONG MID LEVEL THETA-E ADVECTION IS SEEN ON THE NAM ALONG WITH AMPLE ELEVATED INSTABILITY AND LAYER DIVERGENCE ALOFT. IN ADDITION...THERE IS AN 850-300MB THICKNESS RIDGE PASSING ACROSS THE MN CWA SATURDAY MORNING WHICH COINCIDES WELL WITH AN AREA OF MODERATE DIFFERENTIAL TEMPERATURE ADVECTION. SATURDAY EVENING/NIGHT COULD BE INTERESTING IF WE CAN RECOVER FROM THE EXPECTED DAYTIME PRECIPITATION. THIS IS DUE TO A SURFACE WAVE MOVING ACROSS THE SOUTHERN THIRD OF MN. SHEAR PARAMETERS FORECAST BY THE NAM ARE SUPPORTIVE OF SEVERE STORMS...ESPECIALLY THE EASTERN HALF OF THE CWA. BUT AGAIN...MUCH OF THIS DEPENDS ON WHAT HAPPENS ON SATURDAY. FOR NOW WILL MAINTAIN CHANCE POPS. MINOR CHANGES MADE TO ONGOING LOW/HIGH TEMPERATURE FORECASTS. .LONGER TERM...SUNDAY NIGHT THROUGH THURSDAY HAVE ACCEPTED GFS40 GUIDANCE AS MODEL OF CHOICE DUE TO ITS RECENT DEPICTION OF LAST TWO COOL FRONTAL BOUNDARIES. FORECAST PERIOD BEGINS WITH EXITING OF 50H SHORT WAVE OVER SE CWA. HAVE KEPT SLT POPS OVER EXTREME SE PORTION OF CWA DUE TO WEAK FORCING PER 305K ISENTROPIC SURFACE AND POSSIBILITY COOL FRONT MAY BE SLOWER THEN ANTICIPATED DUE TO DEVELOPING SURFACE WAVE OVER THE MID ATLANTIC STATES. DRY CONDITIONS WILL ENSUE UNTIL TUESDAY...AS ANOTHER FAST MOVING RATHER MOISTURE LIMITED COOL FRONT DIVES INTO CENTRAL MN FROM SOUTHERN ONTARIO. AN IMPRESSIVE DIVERGENCE COUPLET DOES DEVELOP OVER SOUTHEASTERN MN THIS TIME FRAME. DP/DT INDICATING MOISTURE AXIS A TAD FARTHER SOUTH THEN PREVIOUS RUN. RIGHT REAR QUAD OF 250MB JET MAX PROGGED OVER SOUTHWEST FA DURING THE EVENING HOURS ON TUESDAY. DRY WEATHER WILL BE SEEN THEREAFTER...WITH TEMPERATURES THROTTLED BACK AT LEAST ONE CATEGORY DURING REMAINDER OF EXTENDED PERIOD DUE TO COPIOUS AMOUNTS OF COLD AIR ADVECTION AND PERSISTENT CLOSED 50H LOW ORBITING JUST WEST OF JAMES BAY. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ RAH/AZ mn AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO 430 PM CDT THU JUN 22 2006 DISCUSSION... MCV LEFT OVER FROM LAST NIGHTS CONVECTION OVER KS REFIRED RATHER QUICKLY BY MID MORNING OVER WEST CENTRAL MISSOURI AND ORGANIZED INTO ANOTHER MCS. THIS FEATURE IS NOW JUST NORTH OF SZL. CURRENT CONVECTION OVER FAR EASTERN COUNTIES SHOULD EXIT THE CWA IN ANOTHER 1-2 HOURS. STRONG SUBSIDENCE BEHIND THIS FEATURE IS ALLOWING AT LEAST PARTIAL CLEARING IN IT WAKE. SATELLITE IMAGERY AND SURFACE OBSERVATIONS INDICATE NO TRUE COLD FRONT WENT THROUGH WITH A BOUNDARY STILL LYING FROM SOUTHEAST NE THROUGH CENTRAL IA AND ANOTHER BOUNDARY FROM EAST CENTRAL THROUGH NORTHWEST KS. THIS LATTER BOUNDARY WILL GUIDE ANOTHER MCS WHICH IS ONGOING OVER NORTHWEST KS. EXPECT THIS CONVECTION TO SLIDE SOUTHWEST OF THE CWA TONIGHT. THE HEAVY RAINFALL FROM LAST NIGHT AND TODAY AND A LACK OF DRYING WITH LIGHT WINDS SUGGEST FOG COULD BECOME A PROBLEM LATER TONIGHT. SO HAVE ADDED THIS TO THE FORECAST. MINOR COOLING AT 850MB FOR TOMORROW AND HAVE FOLLOWED MOS GUIDANCE WHICH GIVES US SEASONAL TEMPERATURES. UPPER FLOW WILL BEGIN TO UNDERGO A PATTERN CHANGE STARTING TOMORROW NIGHT AS THE UPPER RIDGE BUILDS WEST OF THE ROCKIES WHILE GENERAL TROUGHING FORMS OVER THE EASTERN U.S...LEAVING US IN A NORTHWEST FLOW PATTERN. THIS WILL MAKE IT TRICKY TRYING TO TIME ANY SHORTWAVES COMING OUT OF THE NORTHERN ROCKIES AND NORTHERN PLAINS FOR THE NEXT 5-7 DAYS. MODELS ARE FAIRLY CONSISTENT IN BRINGING ONE SHORTWAVE AND A WEAK COLD FRONT THROUGH LATE SATURDAY NIGHT AND EARLY SUNDAY MORNING. HAVE ADDED CHANCE POPS FOR PARTS OF THE CWA FOR THIS. ECMWF AND CANADIAN MODELS DEVELOP AND CLOSE OFF AN UPPER TROUGH OVER THE GREAT LAKES AND LOWER OH VALLEY EARLY NEXT WEEK. GFS NOT FOLLOWED AS IT HAS HAD SOME CONSISTENCY ISSUES. UNUSUAL THIS TIME OF YEAR TO SEE THE ATMOSPHERE CLOSE OFF AN UPPER TROUGH AND THEN STALL IT FOR SEVERAL DAYS. FOR NOW WILL FOLLOW PREVIOUS FORECAST AND MAKE ONLY MINOR DAY TO DAY CHANGES. MJ && .PREV DISCUSSION... 318 AM... MAIN FORECAST CONCERN IS FOCUSED ON PRECIPITATION OVER THE NEXT 24 HOURS. OVERALL UPPER PATTERN SHOWS STRONGER UPPER LEVEL LOW NEAR HUDSON BAY AREA...WHILE ACROSS CENTRAL PLAINS...THERE IS A WEAKER SHORT WAVE MOVING ACROSS KANSAS AT THIS TIME. ALSO EMBEDDED IN THIS FLOW ARE MCV TYPE CIRCULATIONS THAT ARE THE RESULT OF ONGOING CONVECTION. ONE OF THESE MCV CIRCULATIONS IS MOVING ALONG THE IOWA MISSOURI BORDER AT THIS TIME...AND ANOTHER IS NOTED IN EAST CENTRAL KANSAS JUST TO THE WEST OF THE FORECAST AREA. ALSO THIS MORNING...WE HAVE BEEN SEEING THE DEVELOPMENT OF A STRONG JET MAX OVER NORTHERN IOWA AND SOUTHERN MINNESOTA AND EXTENDING BACK INTO NORTHERN NEBRASKA. WRF/NAM MODEL HAS THIS UPPER JET INCREASING TO AROUND 100 KTS IN SOUTHERN MINNESOTA AND INTO WISCONSIN THIS MORNING. NORTHERN MISSOURI WILL BE IN THE RIGHT REAR QUAD OF THIS JET THIS MORNING...WHICH SHOULD HELP TO ENHANCE THE ONGOING CONVECTION. THUS WILL PULL CATEGORICAL POPS A LITTLE FURTHER TO THE NORTH FOR THE MORNING HOURS...IN AREA WHERE SURFACE BOUNDARY CURRENTLY RESIDES. FOR THIS AFTERNOON...THE MCS COMPLEX THAT PRODUCED THE SEVERE WEATHER AND HEAVY RAIN OVER KANSAS WEDNESDAY NIGHT SHOULD BE ON THE UPSWING ONCE AGAIN AFTER DIMINISHING SOME THIS MORNING. WRF/NAM MODEL IS SHOWING A SURFACE HIGH DEVELOPING OVER NORTHERN MISSOURI WHICH SEEMS REASONABLE GIVEN THE COLD POOL EFFECTS EXPECTED TO BE REMAINING AFTER MORNING THUNDERSTORM ACTIVITY DIES DOWN A BIT. EFFECTIVE SURFACE BOUNDARY BY MID AFTERNOON SHOULD BE RUNNING FROM JUST SOUTH OF ST LOUIS...INTO SOUTHWEST MISSOURI AND HEAVIER RAIN SHOULD BECOME FOCUSED IN THE VICINITY OF THIS BOUNDARY. WILL PULL CATEGORICAL POPS FURTHER SOUTH IN THE AFTERNOON TO KEEP THEM IN LINE WITH THIS EXPECTED FRONTAL POSITION. ALL THE PRECIPITATION ACTIVITY SHOULD CONTINUE TO BE FOCUSED ACROSS THE SOUTHERN HALF OF MISSOURI TONIGHT AND INTO FRIDAY...AS A SHORT WAVE DEEPENS OVER SOUTHER MISSOURI AND ARKANSAS DURING THE DAY ON FRIDAY. THIS SHOULD RETURN DRIER WEATHER TO NORTHERN MISSOURI. TEMPERATURES WILL BE QUITE TRICKY TODAY GIVEN CLOUD COVER AND PRECIPITATION. TEMPERATURES OVERNIGHT HAVE STAYED UNSEASONABLY WARM...WITH ONLY THE RAIN COOLING OFF SOME AREA. RAIN SHOULD DROP TEMPERATURES IN MOST OF THE FORECAST AREA AT SOME POINT THIS MORNING...WITH ONLY THE SOUTHEAST PART OF THE FORECAST AREA LIKELY STAYING PRETTY WARM THROUGH THE MORNING HOURS. BUT RAIN MOVING INTO THOSE AREAS BY EARLY AFTERNOON SHOULD KEEP ANY BIG WARM UP FROM OCCURRING. SO WILL KEEP TEMPERATURES RANGES AROUND 10 DEGREES FOR TODAY. PC && .PREV DISCUSSION... 541 PM CDT WED... CONVECTIVE INITIATION HAS BEGUN IN THE VICINITY OF CONCORDIA KS WHERE 22Z SURFACE ANALYSIS INDICATED MODEST CONVERGENCE INTO A WEAK LOW CENTER. RUC OBJECTIVE ANALYSIS SHOWS NEARLY 3000 J/KG OF MLCAPE MAXIMIZED ALONG A GENERAL SW-NE ORIENTED STATIONARY FRONT THAT IS DRAPED FROM FAR NRN MO INTO SW KS. VISIBLE SATELLITE IMAGERY CONFIRMS THE PRESENCE OF MUCH BETTER BOUNDARY LAYER MOISTURE REGIONWIDE...NOTED BY WIDESPREAD CUMULUS WHICH HAS LOCALLY BEGUN TO CONGEAL AND TOWER ALONG THIS BOUNDARY. 12Z TOPEKA SOUNDING AND RUC/NAM-WRF PROGS SHOW THAT VERY STEEP MID LEVEL LAPSE RATES HAVE ADVECTED OVER THE REGION BENEATH A NARROW PLUME OF HIGH LEVEL MOISTURE STREAKING NNE FROM PERSISTENT CONVECTION OVER OLD MEXICO. ENHANCED WATER VAPOR IMAGERY ALSO SHOWED A LOW AMPLITUDE SHORTWAVE DEEPENING ACROSS CENTRAL KANSAS AT THIS TIME. ALTHOUGH THE BOUNDARY LAYER OVER ERN KS/NRN MO WILL DECOUPLE SOMEWHAT THIS EVENING...AMPLE VERTICAL SHEAR AIDED BY AN INCREASING NOCTURNAL JET...ALONG WITH AMBIENT INSTABILITY AND CONTINUED LOW-MID LEVEL FORCING...SHOULD ALLOW CURRENTLY SCATTERED CONVECTION TO STEADILY GROW UPSCALE THIS EVENING. THERE MAY BE SOME INITIAL TENDENCY FOR STORMS TO BACK BUILD...HOWEVER GENEROUS DCAPE VALUES AROUND 1000 J/KG SHOULD GRADUALLY LEAD TO OUTFLOW DOMINANCE AND FORWARD PROPAGATION...BRINGING AN EXPECTED MCS INTO THE AREA AROUND MIDNIGHT. THINK THE NAM-WRF HAS GENERAL HANDLE ON CONVECTIVE EVOLUTION...BUT LIKELY MUCH TOO SLOW ON THE EASTWARD PROGRESSION. ANY SEVERE THREAT WILL DEPEND ON THE MATURITY OF THE MCS...WITH DAMAGING WINDS THE PRIMARY CONCERN AND AT LEAST A MODEST THREAT FOR LARGE HAIL GIVEN ENHANCED ELEVATED INSTABILITY. AREA OF CONCERN AT THIS POINT APPEARS TO BE ALONG AND NORTHWEST OF A LINE FROM THE KANSAS CITY METRO TO TRENTON. AT THE VERY LEAST...THIS APPEARS TO BE THE BEGINNING OF THE BEST CHANCE FOR WIDESPREAD SIGNIFICANT RAINFALL FOR WRN MO/ERN KS IN QUITE SOME TIME. BOOKBINDER 325 PM... FORECAST CONCERNS NEXT 24 HOURS WILL BE TIED TO A WEAK FRONT CURRENTLY STRETCHING FROM SOUTHEAST IA THROUGH THE NORTHWEST CORNER OF MO THROUGH SOUTHWEST KS. THE KS PORTION OF THE BOUNDARY HAS MOVED LITTLE OVER THE PAST 36 HOURS AND WILL LIKELY BE THE AREA OF MOST IMPORTANCE THIS EVENING. THE MAIN UPPER SUPPORT FOR THE IA/NORTHWEST MO PORTION OF THE FRONT IS PASSING BY...SO THE FRONT WILL STALL AS IT CROSSES INTO NORTHERN MO. PLENTY OF CU HAS FORMED ACROSS KS THIS AFTERNOON INDICATING MUCH MORE DEPTH TO THE MOISTURE FIELD. CONVECTIVE INHIBITION IS WEAKENING ALONG THE FRONT AND EXPECT CONVECTION TO FORM SOON FROM SOUTHWEST INTO CENTRAL KS. MODELS HAVE BEEN VERY CONSISTENT IN SIGNALING A SHORTWAVE COMING OUT OF CO THIS EVENING AND TRACKING EAST ACROSS KS. NAM-WRF IS FURTHER NORTH THAN THE GFS WHILE THE CANADIAN SHOWS TWO CENTERS BY 12Z THURSDAY WHILE THE UKMET IS AT ABOUT THE SAME LATITUDE BUT A BIT FASTER. FAVOR THE NAM/UKMET SOLUTION WITH CONVECTION INITIATING THIS EVENING ALONG/NORTH OF THE KS FRONT AND TRACK EAST-NORTHEAST INTO NORTHWEST MO LATE THIS EVENING OR SHORTLY AFTER MIDNIGHT. THE RESULTING COLD POOLS WILL SHIFT THE EFFECTIVE FRONT SOUTH WITH CONVECTION POSSIBLY REACHING THE KC METRO BY 12Z THURSDAY. WITH THE UPPER TROUGH STILL OVER KS ON THURSDAY THERE SHOULD BE SOME BACKBUILDING OF CONVECTION EVEN IF THE MCS MOVES AWAY FROM THE CWA IN THE MORNING. HAVE RAISED POPS UP TO CATEGORICAL FOR THURSDAY OVER A LARGE PART OF THE CWA. HAVE ALSO LOWERED MAX TEMPERATURES DUE TO EXTENSIVE CLOUD COVER AND LIKELIHOOD OF SCATTERED STORMS. AM STARTING TO LEAN TOWARDS LESS OF A SEVERE THREAT AND MORE OF A HYDRO PROBLEM AS PRECIPITABLE WATER VALUES WILL BE QUITE HIGH WITH A SLOW MOVING BOUNDARY AND STRONG SHORTWAVE. CORFIDI VECTORS ARE RATHER WEAK WITH 850MB WINDS NEARLY PARALLEL TO THE SURFACE FRONT FAVORING REDEVELOPMENT ON THE BACKSIDE OF ANY CONVECTIVE COMPLEX. MJ UPPER LVL TROUGH LIFTS NE OF THE AREA DURING FRIDAY AS THE FORECAST AREA TRANSITIONS TO A NORTHWEST FLOW PATTERN. SHOWERS AND THUNDERSTORMS WITH THE TROUGH WILL CONTINUE THURSDAY NIGHT AND EXIT THE FORECAST AREA FRIDAY MORNING. SURFACE COLD FRONT OVER SOUTHERN MISSOURI THURSDAY EVENING SHOULD CONTINUE MOVING SOUTHEAST ON FRIDAY AS HIGH PRESSURE AND DRIER AIR OVER THE NORTHERN PLAINS AND GREAT LAKES BUILDS INTO MISSOURI AND EASTERN KANSAS. WEBBER THE MEDIUM RANGE MODEL SOLUTIONS ARE IN MODERATE AGREEMENT FOR THE WEEKEND INTO THE MIDDLE OF NEXT WEEK. A POLAR VORTEX IS FORECAST TO BECOME ESTABLISHED OVER EASTERN CANADA WHILE UPPER RIDGING SETS UP OVER THE WESTERN HALF OF THE CONUS...LEAVING THE FORECAST AREA WITHIN NORTHWEST FLOW ALOFT. SMALLER SCALE SHORTWAVES PROGRESSING WITHIN THE NORTHWEST FLOW COULD BRING A CHANCE FOR PRECIPITATION TO THE AREA DURING THE DAYS 4 TO 7 TIMEFRAME...HOWEVER IT REMAINS DIFFICULT TO PINPOINT THIS FAR OUT. HAVE CONTINUED SLIGHT PRECIPITATION CHANCES SATURDAY NIGHT FOR ONE SUCH POSSIBLE DISTURBANCE. OTHERWISE...WENT WITH A DRY FORECAST AND SEASONABLY NORMAL TEMPERATURES FOR THE WEEKEND THROUGH THE MIDDLE OF NEXT WEEK. STOFLET && .EAX WATCHES/WARNINGS/ADVISORIES... MO...NONE. KS...NONE. $$ WFO EAX mo AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE ST LOUIS MO 700 AM CDT THU JUN 22 2006 .DISCUSSION... THE QUASI-STATIONARY FRONT WE'VE BEEN WATCHING FOR THE PAST COUPLE OF DAYS IS TRYING TO MOVE AS OUTFLOW FROM CONVECTION OVER THE PLAINS KICKS THE EFFECTIVE BOUNDARY ALONG. FRONTAL POSITION IS QUITE DIFFICULT TO DISCERN THIS MORNING SINCE THE MCS ACTIVITY OVER KANSAS...NEBRASKA...AND IOWA IS MUDDYING THE WATERS. HOWEVER...IT LOOKS LIKE THE FRONT STRETCHES FROM NORTHEAST KANSAS THROUGH EXTREME NORTHWEST MISSOURI...INTO SOUTHERN IOWA AND CONTINUING EAST THROUGH NORTHERN ILLINOIS. WITH LITTLE IN THE WAY OF UPPER LEVEL FORCING DUE TO ZONAL FLOW ALOFT...SLOW SOUTHEAST PROGRESS IS CONTINUED TO BE EXPECTED AS CONVECTIVE OUTFLOW SHOVES THE FRONT IN FITS AND STARTS THROUGH FRIDAY MORNING. TRYING TO TIME FROPA AT ANY GIVEN LOCATION IS NEXT TO IMPOSSIBLE DUE TO THE FICKLE NATURE OF WHERE AND WHEN THESE MCS'S WILL FORM. HAVE BASICALLY THROWN THE GFS IN THE TRASH DUE TO ITS CONTINUED PROBLEMS WITH CONVECTIVE FEEDBACK. THE NEW NAM/WRF MODEL SEEMS TO HAVE AT LEAST A DECENT HANDLE ON WHAT'S GOING ON OVER THE PLAINS AND WESTERN MISSOURI AT THIS TIME...SO I'VE LEANED HEAVILY ON ITS SOLUTION. HAVE INCREASED POPS ACROSS THE AREA TO 60-70 PERCENT FOR THE NEXT 36 HOURS OR SO AS THE FRONT MAKES ITS SLOW PROGRESS THROUGH THE CWFA. I'M NOT CONFIDENT ENOUGH TO SAY CATEGORICALLY THAT IT WILL RAIN AT ANY GIVEN LOCATION DURING THAT TIME-FRAME DUE TO THE LACK OF STRONG FORCING...BUT IT SURE SEEMS LIKELY THAT A MAJORITY OF THE AREA WILL SEE AT LEAST SOME RAIN. SOME AREAS OVER CENTRAL OR SOUTHEAST MISSOURI MAY RECEIVE LOCALLY HEAVY RAIN ESPECIALLY TONIGHT AS THE FRONT INTERACTS WITH A WEAK LOW LEVEL JET AND SMALL SHORTWAVE TROF ALOFT. BUT AGAIN...SIGNALS ARE VERY WEAK...SO HAVEN'T HIGHLIGHTED ANYTHING IN THE FORECAST JUST YET. MAY MENTION IT IN THE HWO LATER... THE FRONT SHOULD FINALLY MOVE SOUTH OF THE AREA FRIDAY NIGHT OR EARLY SATURDAY MORNING BRINGING AN END TO THE PRECIP CHANCES. THIS FINAL PUSH SEEMS TO BE AT LEAST PARTLY IN RESPONSE TO AN AMPLIFYING UPPER PATTERN AS A STRONG RIDGE BUILDS OVER THE SOUTHWEST CONUS AND A LOW DEEPENS OVER THE HUDSON BAY REGION. THIS SHOULD PUT THE MIDWEST BACK INTO NORTHWEST FLOW ALOFT AND ALLOW A CANADIAN AIRMASS TO BUILD INTO THE GREAT LAKES REGION BRINGING OUR AREA RELATIVELY COOLER AND DRIER WEATHER FOR SATURDAY AND SUNDAY. CARNEY && .AVIATION... FOR THE 12Z TAFS...MCS CENTERED OVR SE IA IS MOVING TO THE EAST WITH CONVECTION AS FAR SOUTH AS CNTRL MO ON ITS SW FLANK. THE CELLS ON THE SW FLANK ARE MOVING TO THE NE. THIS MOTION ALG WITH THE MOVEMENT OF THE MCS SHOULD BRING SHRA/TSRA INTO UIN THIS MRNG. THE INITIAL QUESTION IS HOW FAR SOUTH ANY NEW DEVELOPMENT WILL OCCUR ON THE SW FLANK OF THE MCS. THERE IS A RATHER PRONOUNCED OUTFLOW BNDRY AND THE RUC SHOWS DECENT H85 MOISTURE CONVERGENCE THRU CNTRL MO...SO HAVE OPTED TO INCLUDE A TEMPO GROUP THIS MRNG IN THE COU TAF IN LIGHT OF THE POTENTIAL. THIS OUTFLOW IF IT LASTS COULD MORE OR LESS BECOME THE EFFECTIVE FORCING MECHANISM FOR PCPN TDA. OTHERWISE ANTICIPATING A THREAT OF SHRA/TSRA TO COME WITH THE FRONTAL BNDRY. THE FRONT IS DIFFICULT TO DISCERN ATTM BUT STILL APPEARED TO BE DRAPPED ACRS IA INTO NRN KS. THE MODELS ARE HAVING A DIFFICULT TIME RESOLVING THE FRONT...BUT THE GREATEST CONSENSUS WOULD BRING THE FRONT TO AROUND I-70 BY 00Z AND THEN SLOWLY SINK IT SOUTH INTO THE OZARKS TONIGHT. I HAVE PROB OR TEMPO GROUP TO ACCT FOR THE POSSIBILITY OF ANOTHER ORGANIZED THUNDERSTORM COMPLEX WITH THE FRONT LATER THIS AFTERNOON INTO THE EVENING AND THEN REMOVED THE PCPN CHANCES FEELING THE BEST CHANCES WILL SHIFT SOUTH OF THE TAF SITES. GLASS && .LSX WATCHES/WARNINGS/ADVISORIES... MO...NONE. IL...NONE. && $$ WFO LSX mo AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GLASGOW MT 935 AM MDT THU JUN 22 2006 .SHORT TERM...FOR NORTHEAST MONTANA...TODAY THROUGH SATURDAY... UPDATES TO INCREASE CHANCES AND COVERAGE FOR THUNDERSTORMS THIS AFTERNOON AND EVENING. LATEST RUN OF WRF...AND RUC...INCREASE INSTABILITY ACROSS CENTRAL MONTANA THIS AFTERNOON...SO EXTENDED SLIGHT CHANCE AREA INTO SOUTHWEST ZONES LATE THIS AFTERNOON. DUE TO THIS CHANGE LATE IN FIRST PERIOD...EXPANDED CHANGES INTO EVENING PERIOD...WITH SLIGHT CHANCE OF THUNDERSTORMS ACROSS MOST OF FORECAST AREA UNTIL MIDNIGHT. INCREASED SKY GRIDS COMMENSURATE WITH CHANGES TO POPS. SLIGHT INCREASE TO DEW POINTS AND HUMIDITY TODAY TO ACCOUNT FOR INCREASED POPS OVER SOUTHWEST. WINDS AND MAXIMA LOOK OK. PREVIOUS SHORT TERM... FAIRLY BLAND FORECAST FOR THE NEXT SEVERAL DAYS AS NEARLY ZONAL FLOW GRADUALLY BECOMES NORTHWEST AS UPPER RIDGE BUILDS OVER THE WESTERN STATES. WESTERLY FLOW ACROSS THE REGION TODAY WITH HIGH PRESSURE AT THE SURFACE. THIS WILL SHUT DOWN THE STRONG SURFACE WINDS FROM THE LAST FEW DAYS SO WILL NOT NEED LAKE WIND ADVISORY. OTHERWISE STILL SOME WEAK ENERGY AND MOISTURE MOVING THROUGH THE UPPER FLOW WITH SLIGHT INSTABILITY LINGERING AT THE SURFACE...COULD RESULT IN A LITTLE CONVECTION THIS AFTERNOON AND EVENING. NOT MUCH AT LOW LEVELS TO FOCUS LIFT OTHER THAN POSSIBILITY OF WEAK LEE TROF DEVELOPING IN CENTRAL MONTANA. STRONGER WAVE EXPECTED ON FRIDAY WITH SURFACE FRONT ASSOCIATED WITH IT. WITH HIGH PRESSURE MOVING INTO DAKOTAS...SHOULD SEE RISING DEW POINTS ACROSS THE EAST IN SOUTHEAST LOW LEVEL FLOW. BEST CHANCE OF CONVECTION WILL BE ACROSS THE EAST IN ADVANCE OF THE FRONT...IN THE AFTERNOON AND EVENING. HIGH PRESSURE RETURNS ON SATURDAY WITH BUILDING WESTERN RIDGE PUSHING UPPER VORTICITY STREAMS FURTHER NORTH FOR DRY FORECAST. EBERT .LONG TERM...SATURDAY NIGHT THROUGH THURSDAY... EXTENDED PERIOD BEGINS WITH THE UPPER SHORTWAVE MOVING TOWARDS THE GREAT LAKES AS AN UPPER RIDGE BUILDS OVER THE WEST FROM A LARGE HIGH OVER THE SOUTHWEST STATES. MODELS ARE IN GENERAL AGREEMENT INITIALLY WITH UPPER NORTHWEST FLOW OVER THE FORECAST AREA. EXPECT SLIGHTLY WARMER THAN SEASONAL TEMPERATURES AND MOSTLY DRY CONDITIONS WITH THIS PATTERN FOR THE WEEKEND. BY THE END OF THE WEEKEND THE DGEX MODEL PARTS WAYS WITH GFS AND ECMWF. BOTH GFS AND ECMWF MAINTAIN THE RIDGE THROUGH MONDAY AND BRING AN UPPER LOW OFF THE GULF OF ALASKA INTO NORTHERN BRITISH COLUMBIA. ECMWF THEN IS MUCH QUICKER IN BRINGING THE CLOSED LOW SOUTH INTO THE PACIFIC NORTHWEST WHICH WOULD INITIATE COOLER FLOW OVER THE FORECAST AREA...A TREND NOT SEEN IN THE GFS. MODELS DIVERGE GREATLY BY THE END OF THE EXTENDED PERIOD. GIVEN LARGE CHANGES IN MODELS...WILL POSTPONE CHANGES BEYOND MONDAY IN HOPES OF SEEING GREATER MODEL CONTINUITY AND AGREEMENT WITH FUTURE RUNS. THEREFORE IN AGREEMENT WITH SURROUNDING OFFICES KEPT TEMPERATURES ON THE WARM SIDE OF THE ENSEMBLES. SCT && .AVIATION... VFR NEXT 24 HOURS. BUILDING SURFACE HIGH PRESSURE WILL ALLOW FOR LIGHT AND VARIABLE WINDS FOR THE FIRST TIME IN MANY DAYS. EXPECT JUST FEW TO SCATTERED FLAT CUMULUS TO FORM AROUND 7-8K FT AGL FOR TODAY. HOWEVER...A WEAK UPPER LEVEL DISTRUBANCE WILL CAUSE A SLIGHT CHANCE OF THUNDERSTORMS MAINLY FROM THE KGGW AREA WESTWARD FROM MID AFTERNOON THROUGH THIS EVENING. -MDP && .GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE. && $$ WEATHER.GOV/GLASGOW mt AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BINGHAMTON NY 1040 AM EDT THU JUN 22 2006 .SHORT TERM (TODAY - FRI NGT)... UPDATE...MRNG SHWRS HAVE NOW PULLED EAST AND WE ARE NOW AWAITING SCT AFTN CONV TO DVLP. WRF DERIVED MODEL SNDGS CAPES A BIT HI AS THE MODEL SEEMS TO STILL HAVE TOO MUCH LOW LVL MOISTURE...AND DEW PTS ARE TOO HIGH. STILL...MODIFYING 12Z RAOBS GIOVES CAPES NEAR 1500 J/KG SO AFTN CONV SEEMS LIKELY WITH THE LACK OF ANY SIGNIFICANT CAP. WITHOUT ANY REAL TRIGGER...WLD IMAGINE LAKE BNDRIES AND TERRAIN WILL FOCUS INITIAL BLD UPS. MAIN CNCNR FOR ANY SVR WLD BE HAIL AND GUSTY WINDS WITH A BIT OF A MID LVL DRY PUNCH MVG IN. WITH SOME MID AND UPPER LVL CONV DEBRIS ARND...AND PLENTY OF CU...BELIEVE FCSTD MAX TEMPS A BIT HIGH SO HAVE LWRD. OTRW...JUST ADJUSTED GRIDS FOR CRNT CONDS AND REISSUED. PRVS DISC CONTS BLO. MORFORD WHAT LOOKED LIKE A PRETTY GOOD BET FOR MCS ACTIVITY THIS MORNING HAS TURNED INTO ANYTHING BUT. LARGE SCALE COMPLEX RAKING NORTHERN OH IS GRADUALLY TURNING SOUTHEAST INTO WV/PA WITH BACK-BUILDING INTO NW OH. ADDNL CONVECTIVE DEVELOPMENT ACROSS SOUTHERN ONTARIO IS PUSHING OFF TO THE NORTHEAST TOWARD QUEBEC. CONVECTION OUT AHEAD OF MAIN MCS MOVING ACROSS NORTH-CENTRAL PA WILL PUSH INTO SOUTHERN PORTIONS OF FA IN THE NEXT SEVERAL HOURS. EVOLUTION FROM THERE IS MURKY...AS IS ANY MORE DEVELOPMENT THIS MORNING. 00Z MODELS ALL HAD HARD TIME WITH INITIALIZATION OF QPF FIELDS. GFS INITIALIZED TOO FAR NORTH WITH COMPLEX AND AS A RESULT...IS TOO FAR NORTH WITH LOCATION BY 12Z. RUC ALSO DID POOR JOB WITH INITIALIZATION BUT HAS SO FAR CAUGHT ONTO TREND OF DROPPING IT SOUTHEAST THRU MORNING. LOCAL AND OPERATIONAL WRF ALSO DID NOT PICK UP ON NORTHERN OH CONVECTION BUT DID INITIALLY SEE DEVELOPMENT ACROSS SOUTHERN ONTARIO. HOWEVER...BOTH MODELS EXPLODE CONVECTION AND MOVE IT EAST INTO FA BTWN 10-12Z. IN REALITY...WHAT LITTLE DEVELOPMENT OCCURRED HAS LONG SINCE WEAKENED. HAVING SAID ALL THAT...CONFIDENCE IN ANY MODEL SOLN IS EXTREMELY LOW FOR THE FIRST 6 HRS AS TO WHETHER ANY ADDNL DEVELOPMENT WILL OCCUR THIS MORNING. WRF BUFKIT SNDGS INDICATE LITTLE ELEVATED INSTABILITY WILL MAKE IT INTO FA TODAY. THIS IS MUCH WEAKER THAN YESTERDAY WHEN MODELS WERE INDICATING 1000-1500 J/KG CAPE WOULD BE IN PLACE. H8 LLJ HAS ALSO FAILED TO MATERIALIZE...WITH MAIN CORE BEING SHOWN BY RUC ACROSS SEPA RATHER THAN UPSTATE NY AS INDICATED WITH PREVIOUS 00Z RUN. WILL WAIT UNTIL LAST POSSIBLE MINUTE BEFORE ISSUANCE TO SEE WHETHER ANY MORE DEVELOPMENT OCCURS. GIVEN CURRENT RADAR TRENDS...HIGHEST POPS WILL BE ACROSS SOUTHERN ZONES THEN TAPERING TO LO CHC POPS ACROSS NORTH. SCTD STORMS STILL EXPECTED TO DEVELOP THIS AFTERNOON JUST ABOUT ANYWHERE. 00Z WRF HINTING AT PRE-FRONTAL TROF TO OUR NORTH BY EARLY EVENING WITH CONVECTION SPREADING AHEAD OF IT. DRYING ALOFT WILL WORK IN...ALLOWING INSTABILITY TO INCREASE. MODEL DEWPTS MAY BE SLIGHTLY OVERDONE...BUT STILL THINK MID-UPPER 60S REASONABLE. THIS WOULD YIELD CAPES ON ORDER OF 1000-2000 J/KG AND LI/S ARND -5C. UNIDIRECTIONAL FLOW AND LOW WET-BULB ZEROES FVRBL FOR DAMAGING WIND GUSTS AND/OR HAIL WITH ANY STORMS THIS AFTERNOON. AS IF IMMEDIATE SHORT-TERM WEREN/T BAD ENOUGH...MODELS DIVERGE RAPIDLY WITH FRONTAL PASSAGE ON FRIDAY. GFS STILL FASTER WITH MOVEMENT OF FRONT...BUT STALLS IT FURTHER TO THE NORTH. WITH THIS SCENARIO...DEVELOPING WAVE THAT RIDES UP FRI NIGHT WOULD DUMP HEAVY RAINFALL ACROSS SOUTHEASTERN ZONES FROM 00-12Z SAT...WITH GFS INDICATING 3.00+ INCHES ACROSS CATSKILLS. OPERATIONAL WRF SAGS BOUNDARY FURTHER SOUTH WITH LIGHTER QPF IN THESE AREAS. HAVE GONE WITH A COMPROMISE BTWN GFS/WRF. 00Z WRF ALSO SHOWING SPURIOUS HEAVY PCPN BAND TO NORTHWEST OF SFC FRONT 00Z SATURDAY IN REGION OF STRONG FRONTOGENESIS. NOT SURE IF THIS IS A RESULT OF CONVECTIVE FEEDBACK OR IF FEATURE MAY BE REAL...BUT WOULD TEND TO DISCOUNT THIS FOR NOW. IF GFS VERIFIES...EXTREMELY WET PATTERN IS SETTING UP FOR THE NORTHEAST/NEW ENGLAND WITH INCREASED FLOODING THREAT FOR OUR SOUTHEAST COUNTIES BY EARLY NEXT WEEK. -PB && .LONG RANGE (SAT - WED)... FOLLOWED HPC GUIDANCE CLOSELY FOR ENTIRE EXTENDED. BOUNDARY REMAINS OVER SRN PTN OF CWA OR JUST TO THE SOUTH OF REGION THROUGH MONDAY. POP GRADIENT THROUGH PERIOD WILL BE NORTH TO SOUTH WITH AREAS OVER SRN PTN OF CWA POSSIBLY RECEIVING SIGNIFICANT RAINFALL FROM CONVECTION. ON TUESDAY, BOUNDARY MAY LIFT FAR ENOUGH NORTH FOR AREA TO RESIDE IN WARM SECTOR FOLLOWED BY FROPA ON WEDNESDAY. RRM && .AVIATION (22/12Z TO 23/12Z)... VFR THROUGHOUT PERIOD. SOME SHOWERS FIRST 2 HOURS. CIGS DROP TO 4 OR 5K FT...THEN MOVE EAST MIDDAY. SOME TS AGAIN POSSIBLE THIS AFTERNOON BUT NOT ENOUGH CERTAINTY FOR EVEN A TEMPS. WINDS OUT OF SW AT 5 TO 10 KTS THEN INCREASE TO AROUND 10 KTS AND SHIFT TO W. WINDS TONIGHT AGAIN LIGHT AND VARIABLE. TAC && .BGM WATCHES/WARNINGS/ADVISORIES... .NY...NONE. .PA...NONE. && $$ ny AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BINGHAMTON NY 820 AM EDT THU JUN 22 2006 .AVIATION (22/12Z TO 23/12Z)... VFR THROUGHOUT PERIOD. SOME SHOWERS FIRST 2 HOURS. CIGS DROP TO 4 OR 5K FT...THEN MOVE EAST MIDDAY. SOME TS AGAIN POSSIBLE THIS AFTERNOON BUT NOT ENOUGH CERTAINTY FOR EVEN A TEMPS. WINDS OUT OF SW AT 5 TO 10 KTS THEN INCREASE TO AROUND 10 KTS AND SHIFT TO W. WINDS TONIGHT AGAIN LIGHT AND VARIABLE. TAC && .SHORT TERM (TODAY - FRI NGT)... WHAT LOOKED LIKE A PRETTY GOOD BET FOR MCS ACTIVITY THIS MORNING HAS TURNED INTO ANYTHING BUT. LARGE SCALE COMPLEX RAKING NORTHERN OH IS GRADUALLY TURNING SOUTHEAST INTO WV/PA WITH BACK-BUILDING INTO NW OH. ADDNL CONVECTIVE DEVELOPMENT ACROSS SOUTHERN ONTARIO IS PUSHING OFF TO THE NORTHEAST TOWARD QUEBEC. CONVECTION OUT AHEAD OF MAIN MCS MOVING ACROSS NORTH-CENTRAL PA WILL PUSH INTO SOUTHERN PORTIONS OF FA IN THE NEXT SEVERAL HOURS. EVOLUTION FROM THERE IS MURKY...AS IS ANY MORE DEVELOPMENT THIS MORNING. 00Z MODELS ALL HAD HARD TIME WITH INITIALIZATION OF QPF FIELDS. GFS INITIALIZED TOO FAR NORTH WITH COMPLEX AND AS A RESULT...IS TOO FAR NORTH WITH LOCATION BY 12Z. RUC ALSO DID POOR JOB WITH INITIALIZATION BUT HAS SO FAR CAUGHT ONTO TREND OF DROPPING IT SOUTHEAST THRU MORNING. LOCAL AND OPERATIONAL WRF ALSO DID NOT PICK UP ON NORTHERN OH CONVECTION BUT DID INITIALLY SEE DEVELOPMENT ACROSS SOUTHERN ONTARIO. HOWEVER...BOTH MODELS EXPLODE CONVECTION AND MOVE IT EAST INTO FA BTWN 10-12Z. IN REALITY...WHAT LITTLE DEVELOPMENT OCCURRED HAS LONG SINCE WEAKENED. HAVING SAID ALL THAT...CONFIDENCE IN ANY MODEL SOLN IS EXTREMELY LOW FOR THE FIRST 6 HRS AS TO WHETHER ANY ADDNL DEVELOPMENT WILL OCCUR THIS MORNING. WRF BUFKIT SNDGS INDICATE LITTLE ELEVATED INSTABILITY WILL MAKE IT INTO FA TODAY. THIS IS MUCH WEAKER THAN YESTERDAY WHEN MODELS WERE INDICATING 1000-1500 J/KG CAPE WOULD BE IN PLACE. H8 LLJ HAS ALSO FAILED TO MATERIALIZE...WITH MAIN CORE BEING SHOWN BY RUC ACROSS SEPA RATHER THAN UPSTATE NY AS INDICATED WITH PREVIOUS 00Z RUN. WILL WAIT UNTIL LAST POSSIBLE MINUTE BEFORE ISSUANCE TO SEE WHETHER ANY MORE DEVELOPMENT OCCURS. GIVEN CURRENT RADAR TRENDS...HIGHEST POPS WILL BE ACROSS SOUTHERN ZONES THEN TAPERING TO LO CHC POPS ACROSS NORTH. SCTD STORMS STILL EXPECTED TO DEVELOP THIS AFTERNOON JUST ABOUT ANYWHERE. 00Z WRF HINTING AT PRE-FRONTAL TROF TO OUR NORTH BY EARLY EVENING WITH CONVECTION SPREADING AHEAD OF IT. DRYING ALOFT WILL WORK IN...ALLOWING INSTABILITY TO INCREASE. MODEL DEWPTS MAY BE SLIGHTLY OVERDONE...BUT STILL THINK MID-UPPER 60S REASONABLE. THIS WOULD YIELD CAPES ON ORDER OF 1000-2000 J/KG AND LI/S ARND -5C. UNIDIRECTIONAL FLOW AND LOW WET-BULB ZEROES FVRBL FOR DAMAGING WIND GUSTS AND/OR HAIL WITH ANY STORMS THIS AFTERNOON. AS IF IMMEDIATE SHORT-TERM WEREN/T BAD ENOUGH...MODELS DIVERGE RAPIDLY WITH FRONTAL PASSAGE ON FRIDAY. GFS STILL FASTER WITH MOVEMENT OF FRONT...BUT STALLS IT FURTHER TO THE NORTH. WITH THIS SCENARIO...DEVELOPING WAVE THAT RIDES UP FRI NIGHT WOULD DUMP HEAVY RAINFALL ACROSS SOUTHEASTERN ZONES FROM 00-12Z SAT...WITH GFS INDICATING 3.00+ INCHES ACROSS CATSKILLS. OPERATIONAL WRF SAGS BOUNDARY FURTHER SOUTH WITH LIGHTER QPF IN THESE AREAS. HAVE GONE WITH A COMPROMISE BTWN GFS/WRF. 00Z WRF ALSO SHOWING SPURIOUS HEAVY PCPN BAND TO NORTHWEST OF SFC FRONT 00Z SATURDAY IN REGION OF STRONG FRONTOGENESIS. NOT SURE IF THIS IS A RESULT OF CONVECTIVE FEEDBACK OR IF FEATURE MAY BE REAL...BUT WOULD TEND TO DISCOUNT THIS FOR NOW. IF GFS VERIFIES...EXTREMELY WET PATTERN IS SETTING UP FOR THE NORTHEAST/NEW ENGLAND WITH INCREASED FLOODING THREAT FOR OUR SOUTHEAST COUNTIES BY EARLY NEXT WEEK. -PB && .LONG RANGE (SAT - WED)... FOLLOWED HPC GUIDANCE CLOSELY FOR ENTIRE EXTENDED. BOUNDARY REMAINS OVER SRN PTN OF CWA OR JUST TO THE SOUTH OF REGION THROUGH MONDAY. POP GRADIENT THROUGH PERIOD WILL BE NORTH TO SOUTH WITH AREAS OVER SRN PTN OF CWA POSSIBLY RECEIVING SIGNIFICANT RAINFALL FROM CONVECTION. ON TUESDAY, BOUNDARY MAY LIFT FAR ENOUGH NORTH FOR AREA TO RESIDE IN WARM SECTOR FOLLOWED BY FROPA ON WEDNESDAY. RRM && .BGM WATCHES/WARNINGS/ADVISORIES... .NY...NONE. .PA...NONE. && $$ ny AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE RALEIGH NC 944 PM EDT THU JUN 22 2006 .SYNOPSIS... THE UPPER LEVEL RIDGE AXIS WAS CENTERED JUST SOUTHWEST OF CENTRAL NC THIS EVENING. THE SURFACE HIGH (1020 MB) WAS CENTERED OFFSHORE. THE RESULTANT SE-S RETURN FLOW ALLOWED SURFACE DEW POINTS TO RISE AT OR ABOVE 70 AT MOST LOCATIONS THIS AFTERNOON AND EVENING. && .SHORT TERM /THROUGH TONIGHT/... THE DIURNAL MOUNTAIN CONVECTION HAD DIED OFF AS OF 930 PM. ONLY SCATTERED TO BROKEN CIRRUS AND A FEW MID CLOUDS REMAINED... MAINLY OVER THE WESTERN AND SOUTHERN PIEDMONT. 900 PM TEMPS WERE STILL VERY WARM... BETWEEN 80 AND 85... EXCEPT A FEW UPPER 70S IN RURAL AREAS OF THE N-E PIEDMONT AND COASTAL PLAIN. NO BIG CHANGES TO THE FORECAST OVERNIGHT. THE LOW CHANCE POP WILL BE ELIMINATED FOR THE REST OF THE EVENING SINCE THE CONVECTION DIED OFF A LITTLE AHEAD OF SCHEDULE. LOWS SHOULD ONLY DROP INTO UPPER 60S TO LOWER 70S... AFTER THE HOTTEST DAY OF THE YEAR AT MANY PIEDMONT LOCATIONS (RDU AND GSO 95). URBAN CENTERS WILL REMAIN AT OR ABOVE 70 WHICH WILL BE REFLECTED IN THE GRAPHICAL FORECAST. AS THE UPPER RIDGE SLIDES A LITTLE MORE SOUTH ON FRIDAY... WITH A CONTINUED INFLUX OF BOUNDARY LAYER MOISTURE WITH A SE-S FLOW... EXPECT TO SEE INCREASED COVERAGE OF DIURNAL THUNDERSTORM ACTIVITY... ESPECIALLY FROM THE PIEDMONT INTO THE MOUNTAINS. && .PREV DISCUSSION... (ISSUED 305 PM EDT THU JUN 22 2006) SHORT TERM /TONIGHT THROUGH SUNDAY/... TONIGHT: HEAT INDEX VALUES HAVE BEEN MOSTLY ON TARGET THIS AFTERNOON... TOPPING OUT IN THE 100-103 DEGREE RANGE THIS AFTERNOON. SCATTERED STORMS POPPED UP EARLY ALONG THE MOUNTAINS AND FOOTHILLS ALONG A WEAK BUT PERSISTENT LOW LEVEL CONVERGENCE ZONE. BOUNDARY LAYER FLOW HAS BEEN DIFFLUENT TO THE EAST OVER CENTRAL AND EASTERN NC... AND THE LATEST RUC SHOWS THE LOW LEVEL BOUNDARY HOLDING JUST NORTHWEST OF THE RAH CWA INTO THE EVENING. LAPS FORECAST SOUNDINGS HOWEVER STILL INDICATE A MODERATELY UNSTABLE COLUMN... ALTHOUGH WITH A VERY WEAK WIND FIELD... ANY CELLS SHOULD GO UP AND DOWN QUICKLY. WILL HOLD ONTO A MENTION OF SCATTERED STORMS IN THE NORTHWEST CWA THIS EVENING. GROUND MAY HAVE DRIED SUFFICIENTLY TODAY TO MINIMIZE WIDESPREAD FOG TONIGHT AND WILL KEEP IT OUT OF THE FORECAST FOR NOW. WILL HAVE LOWS A DEGREE OR TWO BELOW MOS GUIDANCE... ABOUT 68-70. FRIDAY THROUGH SUNDAY: THE MID LEVEL TROUGH APPROACHES FROM THE WEST ON FRIDAY THEN REMAINS QUASISTATIONARY JUST WEST OF THE APPALACHIANS THROUGH SUNDAY. THE ACCOMPANYING FRONT STALLS ALONG THE MOUNTAINS... PLACING NC IN A PATTERN OF INCREASING AND DEEPENING MOISTURE THROUGH THE WEEKEND... PARTICULARLY OVER THE WESTERN HALF OF THE STATE WHERE INCREASING DYNAMIC LIFT ASSOCIATED WITH THE UPPER JET TO OUR NORTH WILL BE AUGMENTED BY A LOW LEVEL CONFLUENT AND UPSLOPE SE TO S FLOW. ALSO TO BE CONSIDERED IS THE WESTWARD MOVING TROPICAL WAVE THAT APPROACHES THE SOUTHEAST COAST WHICH SHOULD FURTHER INCREASE THE PRECIPITABLE WATER VALUES AND THE HEAVY RAIN THREAT. FORECAST SOUNDINGS SHOW THE DEPTH OF THE LCL TO FREEZING LEVEL RISING TO 3-4 KM... AN INDICATOR OF GOOD PRECIPITATION EFFICIENCY. HAVE GONE WITH HIGH CHANCE POPS THROUGH THE PERIOD... PRIMARILY DURING THE AFTERNOON AND EVENING... AND WILL PROBABLY NEED LIKELY POPS AT SOME POINT ONCE WE ARE BETTER ABLE TO PIN DOWN THE TIMING. AS MOISTURE DEEPENS THROUGH THE COLUMN AND CLOUDS CONTINUE TO INCREASE THROUGH THE PERIOD... THE DIURNAL TEMPERATURE SPREAD SHOULD NARROW... WITH INITIAL LOWS GOING FROM THE UPPER 60S TO 70-73 AND HIGHS DROPPING INTO THE LOW-MID 80S BY SUNDAY. LATER SHIFTS MAY NEED TO CONSIDER A FLOOD POTENTIAL OUTLOOK STATEMENT FOR SOME PORTION OF THE CWA FOR THE WEEKEND. LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... WEAK BOUNDARIES OVER THE WESTERN PORTION OF THE AREA WITH HIGH PRESSURE OFF THE COAST. ABUNDANT MOISTURE AT THE SURFACE COMBINED WITH WEAK IMPULSES MOVING THROUGH AN UPPER LEVEL TROUGH WILL RESULT IN SCATTERED SHOWERS AND THUNDERSTORMS THROUGH THE PERIOD. HIGH MONDAY THROUGH WEDNESDAY IN THE 80S TO AROUND 90...AND AROUND 90 THURSDAY. LOWS GENERALLY IN THE MID TO UPPER 60S NORTHWEST TO LOWER 70S IN THE SOUTHEAST. -RHJ AVIATION... HIGH PRESSURE ALONG THE CAROLINA COAST WILL KEEP LIGHT SOUTHWEST WINDS OVER THE TAF AREA...RESULTING IN SCATTERED CUMULUS UNTIL DARK. OTHERWISE CEILINGS UNLIMITED AND VISIBILITY UNRESTRICTED. AFTER 09Z FRIDAY MORNING VISIBILITY OCCASIONALLY LOWERING TO 5 MILES IN HAZE AND FOG. EXCEPT IFR TO LIFR CEILINGS AND VISIBILITY FAY TO RWI 09Z TO 12Z. -RHJ && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS... SHORT TERM...BADGETT nc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE RALEIGH NC 305 PM EDT THU JUN 22 2006 .SHORT TERM /TONIGHT THROUGH SUNDAY/... TONIGHT: HEAT INDEX VALUES HAVE BEEN MOSTLY ON TARGET THIS AFTERNOON... TOPPING OUT IN THE 100-103 DEGREE RANGE THIS AFTERNOON. SCATTERED STORMS POPPED UP EARLY ALONG THE MOUNTAINS AND FOOTHILLS ALONG A WEAK BUT PERSISTENT LOW LEVEL CONVERGENCE ZONE. BOUNDARY LAYER FLOW HAS BEEN DIFFLUENT TO THE EAST OVER CENTRAL AND EASTERN NC... AND THE LATEST RUC SHOWS THE LOW LEVEL BOUNDARY HOLDING JUST NORTHWEST OF THE RAH CWA INTO THE EVENING. LAPS FORECAST SOUNDINGS HOWEVER STILL INDICATE A MODERATELY UNSTABLE COLUMN... ALTHOUGH WITH A VERY WEAK WIND FIELD... ANY CELLS SHOULD GO UP AND DOWN QUICKLY. WILL HOLD ONTO A MENTION OF SCATTERED STORMS IN THE NORTHWEST CWA THIS EVENING. GROUND MAY HAVE DRIED SUFFICIENTLY TODAY TO MINIMIZE WIDESPREAD FOG TONIGHT AND WILL KEEP IT OUT OF THE FORECAST FOR NOW. WILL HAVE LOWS A DEGREE OR TWO BELOW MOS GUIDANCE... ABOUT 68-70. FRIDAY THROUGH SUNDAY: THE MID LEVEL TROUGH APPROACHES FROM THE WEST ON FRIDAY THEN REMAINS QUASISTATIONARY JUST WEST OF THE APPALACHIANS THROUGH SUNDAY. THE ACCOMPANYING FRONT STALLS ALONG THE MOUNTAINS... PLACING NC IN A PATTERN OF INCREASING AND DEEPENING MOISTURE THROUGH THE WEEKEND... PARTICULARLY OVER THE WESTERN HALF OF THE STATE WHERE INCREASING DYNAMIC LIFT ASSOCIATED WITH THE UPPER JET TO OUR NORTH WILL BE AUGMENTED BY A LOW LEVEL CONFLUENT AND UPSLOPE SE TO S FLOW. ALSO TO BE CONSIDERED IS THE WESTWARD MOVING TROPICAL WAVE THAT APPROACHES THE SOUTHEAST COAST WHICH SHOULD FURTHER INCREASE THE PRECIPITABLE WATER VALUES AND THE HEAVY RAIN THREAT. FORECAST SOUNDINGS SHOW THE DEPTH OF THE LCL TO FREEZING LEVEL RISING TO 3-4 KM... AN INDICATOR OF GOOD PRECIPITATION EFFICIENCY. HAVE GONE WITH HIGH CHANCE POPS THROUGH THE PERIOD... PRIMARILY DURING THE AFTERNOON AND EVENING... AND WILL PROBABLY NEED LIKELY POPS AT SOME POINT ONCE WE ARE BETTER ABLE TO PIN DOWN THE TIMING. AS MOISTURE DEEPENS THROUGH THE COLUMN AND CLOUDS CONTINUE TO INCREASE THROUGH THE PERIOD... THE DIURNAL TEMPERATURE SPREAD SHOULD NARROW... WITH INITIAL LOWS GOING FROM THE UPPER 60S TO 70-73 AND HIGHS DROPPING INTO THE LOW-MID 80S BY SUNDAY. LATER SHIFTS MAY NEED TO CONSIDER A FLOOD POTENTIAL OUTLOOK STATEMENT FOR SOME PORTION OF THE CWA FOR THE WEEKEND. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... WEAK BOUNDARIES OVER THE WESTERN PORTION OF THE AREA WITH HIGH PRESSURE OFF THE COAST. ABUNDANT MOISTURE AT THE SURFACE COMBINED WITH WEAK IMPULSES MOVING THROUGH AN UPPER LEVEL TROUGH WILL RESULT IN SCATTERED SHOWERS AND THUNDERSTORMS THROUGH THE PERIOD. HIGH MONDAY THROUGH WEDNESDAY IN THE 80S TO AROUND 90...AND AROUND 90 THURSDAY. LOWS GENERALLY IN THE MID TO UPPER 60S NORTHWEST TO LOWER 70S IN THE SOUTHEAST. -RHJ && .AVIATION... HIGH PRESSURE ALONG THE CAROLINA COAST WILL KEEP LIGHT SOUTHWEST WINDS OVER THE TAF AREA...RESULTING IN SCATTERED CUMULUS UNTIL DARK. OTHERWISE CEILINGS UNLIMITED AND VISIBILITY UNRESTRICTED. AFTER 09Z FRIDAY MORNING VISIBILITY OCCASIONALLY LOWERING TO 5 MILES IN HAZE AND FOG. EXCEPT IFR TO LIFR CEILINGS AND VISIBILITY FAY TO RWI 09Z TO 12Z. -RHJ && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...HARTFIELD LONG TERM...RHJ AVIATION...RHJ nc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE RALEIGH NC 1032 AM EDT THU JUN 22 2006 .SHORT TERM /REST OF TODAY/... THE MID LEVEL ANTICYCLONE BUILDS ATOP THE AREA THIS AFTERNOON WITH RELATIVELY WARM TEMPERATURES ALOFT LIKELY CLIMBING ABOVE -10C THROUGH THE DAY. THE MCS TRACK WILL HOLD TO OUR NORTH AND NO LARGE SCALE FORCING MECHANISM FOR NC IS EVIDENT IN THE UPPER AIR ANALYSES... ASIDE FROM VERY WEAK CONVERGENCE OVER THE PIEDMONT FROM THE SURFACE THROUGH 925 MB. DESPITE A WEAK CAP ALOFT... MODERATE INSTABILITY IS EXPECTED WITH ADJUSTED RUC FORECAST SOUNDINGS SHOWING CAPE VALUES OVER 1700 J/KG... BUT TOTAL TOTALS ARE A MINISCULE 39. MID LEVEL LAPSE RATES STILL EXCEED 6 C/KM OVER THE NORTHWESTERN CWA... AND GIVEN THE HIGH BOUNDARY LAYER MOISTURE CONTENT AND THE POTENTIAL FOR A WEAK SURFACE BOUNDARY LEFT OVER FROM YESTERDAY'S MCS AND ANY POSSIBLE GROUND MOISTURE FLUX DIFFERENTIAL... FEEL JUSTIFIED LEAVING IN THE CURRENT ISOLATED POPS. WE ARE STARTING THE DAY TRENDING A COUPLE OF DEGREES BELOW THE FORECAST PACE OF TEMPERATURES... BUT HIGHS IN THE MIDDLE 90S STILL APPEAR REACHABLE. -GIH && .PREV DISCUSSION... (ISSUED 653 AM EDT THU JUN 22 2006) SHORT TERM /REST OF TODAY/... QUICK UPDATE ISSUED TO REMOVE PATCHY FOG IN THE PIEDMONT AND CONFINE IT TO THE COASTAL PLAIN AND EASTERN SANDHILLS THIS MORNING. -RFG PREV DISCUSSION... (ISSUED 140 AM EDT THU JUN 22 2006) SHORT TERM /TODAY THROUGH SATURDAY/... THE SUBTROPICAL RIDGE ALOFT BUILDS OVER THE AREA TODAY BUT WITH SUFFICIENT INSTABILITY AND MOISTURE FOR AT LEAST ISOLATED DEEP CONVECTION THIS AFTERNOON AND EVENING. TEMPERATURES APPEAR DESTINED FOR MID 90S AND COMBINED WITH DEW POINTS IN THE 68-71 DEGREE RANGE WILL YEILD HEAT INDICES NEAR 102. A SPEACIAL STATEMENT WILL BE UPDATED FOR POTENTIAL HEAT STRESS TODAY. THE ABOVE NORMAL TEMPERATURES AND MODERATELY MOIST AIRMASS CONTINUES TONIGHT THROUGH SATURDAY...THOUGH BY SATURDAY...THE RIDGE ALOFT BEGINS TO WEAKEN AND WE BEGIN TO LOSE THE WESTERLY COMPONENT IN THE FLOW ALOFT IN FAVOR OF A MORE SOUTHERLY AND EASTERLY FLOW PATTERN. TEMPERATURES SHOULD BACK DOWN BUT STILL MAX ABOVE 90 ON FRI AND CLOSER TO NORMAL UPPER 80S ON SATURDAY WITH DAYTIME CLOUDINESS ON THE INCREASE. -RFG LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... MODELS SUGGEST A PREDOMINANTLY WET PERIOD FOR CENTRAL NC WITH THE POTENTIAL FOR LOCALLY HEAVY RAINFALL AT TIMES FROM AN INFUSION OF TROPICAL MOISTURE. EACH OF THE MODELS SHOWS AN INVERTED TROUGH SETTING UP IN THE LOWER LEVEL FLOW SAT NIGHT-SUN WITH AN AXIS FROM THE NE GULF TO THE UPPER TN VALLEY AND SRN APPALACHIANS. THIS IN COMBINATION WITH A BROAD HIGH PRESSURE SYSTEM NE OF BERMUDA PRODUCES A FLOW OF AIR WITH A LONG FETCH OFF THE SUBTROPICAL ATLANTIC INTO THE CAROLINAS. THIS PATTERN BECOMES QUASI STATIONARY WITH WITH SUBTROPICAL RIDGE POSITIONS FIXED OVER THE WEST COAST AND CENTRAL WESTERN ATLANTIC AND A MEAN TROUGH POSITION OVER THE EASTERN U.S. THE UPPER TROUGH INTENSIFIES AND BASICALLY SETS UP A STATIONARY BOUNDARY OVER THE EAST COAST STATES TO THE SRN APPALACHIANS. THE INTERACTION OF TROPICAL MOISTURE WITH THIS BOUNDARY SHOULD PRODUCE FREQUENT NUMEROUS SHOWERS AND THUNDERSTORMS WITH THE AXIS OF HEAVIEST AND GREATEST RAINFALL COVERAGE YET TO BE DETERMINED. BUT FOR CENTRAL NC...EACH 12 HOURS SEGMENT WILL SHOW ABOVE NORMAL CHANCES OF RAINFALL AND NEAR NORMAL DAYTIME TEMPERATURES. VARIABLE TO MOSTLY CLOUDY SKIES AND DEW POINTS FAVORING THE 70 DEGREE MARK SHOULD KEEP NIGHTTIME LOW TEMPERATURES NEAR OR ABOVE 70. -RFG AVIATION... HIGH HUMIDITY WITH DEW POINTS NEAR 70 BUT RADIATION IS BEING BLOCKED A BIT BY HIGH CLOUDINESS FROM LAST EVENINGS CONVECTION. STILL EXPECT IFR VISIBILITY IN FOG IN THE PREDAWN AT FAY AND RWI WHICH HAD RAIN YESTERDAY AND HAVE ALREADY FALLEN TO MVFR AT ISSUANCE. TODAY...LIGHT SOUTHWEST WIND WITH SCATTERED CUMULUS AROUND 5KFT AS UPPER RIDGING SHOULD SUPPRESS CONVECTION. -MLM && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...HARTFIELD nc AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 1152 AM EDT THU JUN 22 2006 HAVE UPDATED TO SPRUCE UP GRIDS BASED ON CURRENT CONDITIONS. DID NOT CHANGE MUCH IN THE WAY OF TEMPS/POPS/WX FOR THIS AFTERNOON. CLEARING IS SPREADING DOWN FROM THE N AND NW, SO AFTERNOON TEMPS SHOULD GET UP TO FORECAST LEVELS. DO NOT EXPECT ORGANIZED TSTMS TO DEVELOP OR MOVE INTO OUR AREA THIS AFTERNOON, BUT COULD BE SCATTERED TO ISOLATED ACTIVITY AND WITH THE ATMOSPHERE BECOMING MORE UNSTABLE, SOME GUSTY WINDS AND HEAVY RAIN COULD OCCUR. ALSO ADJUSTED POPS AND WX TO FIT MORE WITH SURROUNDING OFFICES FOR LATER TONIGHT AND FRIDAY. WILL REEVALUATE THE HEAVY RAIN THREAT IN THE COMING DAYS FOR THE AFTERNOON PACKAGE. RPW PREVIOUS DISC... .SHORT TERM /TODAY THROUGH FRIDAY NIGHT/... WHAT TO DO WITH THE MCS? THE GFS SEEMS THE FARTHEST FROM REALITY WITH THE BULK OF THE PRECIP RIDING INTO NEW YORK STATE. BOTH THE RUC AND THE NAM ARE TOO SLOW, BUT AT LEAST THEY DO SHOW A SOUTHEAST DRIFT. WE'LL RUN WITH THE NAM THIS MORNING, BUT BASED OFF SAT PIX TRENDS SPEED THINGS UP BY ABOUT THREE HOURS. WITH THE SYSTEM RUNNING INTO STABLE AIR, WHATEVER MAKES IT OVER THE CWA WILL BE IN A WEAKENED FORM. IR IMAGES ARE STARTING TO SHOW SOME WARMING CLOUD TOPS. LIGHTNING IS ALSO STARTING TO WANE. THE CLOUD SHIELD ASSOCIATED WITH THE MCS SHOULD EFFECT US MORE THIS MORNING THAN THIS AFTERNOON. WE'LL SHOW SOME DECREASING CLOUD TRENDS FOR THE NORTHERN HALF OF THE CWA BECAUSE OF THIS. THE MORNING MCS WILL BE REPLACED BY A SURFACE TROF THIS AFTERNOON. IF WE HAD FULL SUN TODAY, MID 90S WOULD BE A GOOD BET ACROSS THE WARMEST LOCALES. ALTHOUGH, MORE SUN IS EXPECTED THIS AFTERNOON, OUR BELIEF IS THAT THERE WILL BE ENOUGH CLOUDINESS AROUND TO AFFECT TEMPERATURES. IT WILL STILL BE HOT AND SOMEWHAT UNCOMFORTABLE. ALTHOUGH AMBIENT TEMPERATURES AREN'T EXPECTED TO GET INTO THE MID 90S, HEAT INDICES WILL AS DEWPOINTS INCH TOWARD 70 DEGREES. WITH THE INCREASE IN MOISTURE THE LAST 24 HOURS COMBINED WITH THIS AFTERNOON'S HEAT, BUFKIT SOUNDINGS SHOW IMPRESSIVE CAPE/LI VALUES. THEY LOOK MORE LEGITIMATE THAN IN THE RECENT PAST WITH FORECAST HIGHS IN THE LOWER 90S. THE NAM, AS OF LATE, HAS BEEN PRODUCING TOO MUCH CAPE DUE TO HIGH TEMPERATURES THAT WERE TOO HIGH. EVEN THE GFS SOUNDINGS ARE IMPRESSIVE. WITH A POSSIBLE SURFACE TROF IN THE VICINITY OR EVEN A BOUNDARY STEMMING FROM ONGOING CONVECTION, THE SPC HAS PLACED MOST OF THE CWA IN SLIGHT RISK. THE WELL ADVERTISED COLD FRONT NOW LOOKS LIKE IT WILL ARRIVE IN THE POCONOS EARLY FRIDAY MORNING. CAPES AND LI'S ARE ONCE AGAIN INDICATING A RIPE ATMOSPHERE FRIDAY AFTERNOON. WHAT'S MORE OF A CONCERN IS THE PW'S THAT ARE BEING FORECAST IN THE AFTERNOON AND INTO FRIDAY NIGHT. THE GFS TOPS OUT AROUND 2.25", WHILE THE NAM CLIMBS UP TO 2.60". WITH ABUNDANT MOISTURE, LOADS OF INSTABILITY, AND WITH A COLD FRONT INVOF, SEVERE THUNDERSTORMS AS WELL AS FLASH FLOODING IS A CONCERN. THE SPC HAS ONCE AGAIN PUT THE REGION IN SLIGHT RISK (PER SWODY2). AN SPS WILL BE ISSUED TO ADDRESS OUR CONCERNS. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... OVERALL THE EXTENDED LOOKS TO BE A VERY WET PERIOD. THE COLD FRONT LOOKS TO STALL OVER OUR REGION ON SATURDAY. THIS FRONT IS THE PRIMARY CAUSE OF CONCERN IN THE EXTENDED AS IT LOOKS LIKE THE FRONT WILL RETROGRADE BACK OVER THE REGION CONTINUING THE ALREADY WET CONDITIONS. PERIODS OF HEAVY RAIN THROUGHOUT THE CWA COULD CAUSE SOME LOCATIONS TO GET CLOSE TO OR OVER 4 INCHES OF RAIN (THIS IS IN ADDITION TO WHAT FALLS TODAY AND FRIDAY). IT LOOKS AS THOUGH THE WET CONDITIONS WILL CONTINUE INTO THE BEGINNING OF THE NEXT WORK WEEK. TEMPERATURES ALSO LOOK TO BE CLOSE TO NORMAL FOR THIS TIME OF THE YEAR. WE'LL CONTINUE WITH THE ESF. && .AVIATION... BY 3:00 AM, SOME MID LEVEL AND HIGH CLOUDS HAD BEGUN TO DRIFT OVERHEAD. THE CLOUDS WERE IN ADVANCE OF A CONVECTIVE COMPLEX LOCATED IN NORTHERN OHIO AND WESTERN PENNSYLVANIA. THE LEADING EDGE OF THE PRECIP ASSOCIATED WITH THE COMPLEX WAS WEAKENING AS IT MOVED INTO THE MORE STABLE AIR OVER CENTRAL AND EASTERN PENNSYLVANIA. MEANWHILE, TSTMS WERE REGENERATING ON THE BACK SIDE OF THE COMPLEX AS MOISTURE WAS ADVECTING UP INTO THE OHIO RIVER VALLEY. WE WE'RE NOT TERRIBLY AGGRESSIVE WITH THE FORWARD PROGRESS OF THE PRECIP INTO OUR FORECAST AREA THIS MORNING. IT APPEARS AS THOUGH THE WEAKENING TREND WILL CONTINUE ON THE LEADING EDGE OF THE COMPLEX. THERE SHOULD BE A FAIR AMOUNT OF DEBRIS CLOUDS THROUGH THE MORNING WITH PERHAPS AN INCREASE IN SUNSHINE FOR THIS AFTERNOON. WITH THE RESULTING DESTABILIZATION OF THE ATMOSPHERE, WE'VE MENTIONED SOME CUMULONIMBUS FOR RDG AND ABE DURING THE LATE AFTERNOON. WE'VE LEFT THE MENTION OUT OF OUR REMAINING SIX TAF SITES FOR THE TIME BEING, WITH LESS OF A CHANCE FOR PRECIP FOR TODAY ON AND NEAR THE COASTAL PLAIN. && .MARINE... WITH THE FRONT EXPECTED TO STALL BEFORE REACHING THE COAST OUR MARINE AREA SHOULD REMAIN IN A BROAD SOUTHERLY FLOW INTO THE WEEKEND. SEAS SHOULD BUILD GRADUALLY DURING THE NEXT FEW DAYS, PERHAPS GETTING NEAR SMALL CRAFT ADVISORY CRITERIA (5 FEET) ON SATURDAY. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...NONE. DE...NONE. MD...NONE. MARINE...NONE. && $$ SHORT TERM...KRUZDLO LONG TERM...MEOLA AVIATION...IOVINO MARINE...IOVINO pa AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE ABERDEEN SD 1048 AM CDT THU JUN 22 2006 .UPDATE...TODAY ADDED A SLIGHT CHANCE FOR SHOWERS AND THUNDERSTORMS ACROSS THE FAR NE COUNTIES FOR THE AFTERNOON. CU FIELD ALREADY DEVELOPING ACROSS THIS AREA AND A WEAK WAVE WILL MOVE THROUGH THIS AFTERNOON. RUC/HI RES NAM SOUNDINGS SHOWING LI VALUES FROM -2 TO -4 OVER THE AREA AND SFC DEWPOINTS WILL BE IN THE MID 50S. REST OF FORECAST LOOKS ON TRACK AND NO OTHER MAJOR CHANGES MADE. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. && $$ TT sd AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NASHVILLE TN 940 AM CDT THU JUN 22 2006 .UPDATE... SEVERE TSTM IN SOUTHWEST KY OVER BENTON KY MOVING NORTHEAST. THIS FEATURE MAY BE ASSOCIATED WITH WEAK UPPER LEVEL VORT CENTER AND ASSOCIATED WEAK COOL POOL AROUND 500 MB ON LATEST RUC RUN WHICH IS PROGGED TO MOVE NORTHEAST. OUTFLOW BOUNDARY IS LURKING IN MIDDLE TENNESSEE FROM CONVECTION THAT COLLAPSED LAST EVENING ALONG PLATEAU AND FAR EASTERN MIDDLE. BOUNDARY RUNNING FROM LEWISBURG TO LEBANON TO LAFAYETTE. HAVE SEEN A FEW SHOWERS WORK NORTH THROUGH THE PULASKI AREA THIS MORNING BUT THESE HAVE PRETTY MUCH DISSIPATED. CURRENT FORECAST LOOKS GOOD AND ON TRACK. LOOKS LIKE ANOTHER WARM DAY HERE IN MIDDLE TN WITH SOME LOCATIONS REACHING THE MID 90S. BOYD && .PREV DISCUSSION... (ISSUED 400 AM CDT THU JUN 22 2006) DISCUSSION... A COUPLE OF LOW PRESSURE TROUGHS. AN WEAK TROUGH LIES FROM NRN OK TO NRN MO TO NRN OH. FURTHER N...A LOW PRESSURE TROUGH LIES FROM NORTH DAKOTA EWD ACROSS MN TO A STRONG SFC LOW IN E CNTRL CANADA. 500MB HGHTS DROP FROM THEIR CURRENT 591 DM DOWN TO 585 DM BY SAT AM AS THE H5 LOW OVER HUDSON BAY DEEPENS A BIT. AS THE ASSOCD CANADIAN SFC RIDGE PRESSES THE 2 TROUGHS SWD THE GFS MODEL DEVELOPS A FAIRLY INTENSE SFC LOW OVER THE MISS VALLEY THU NGT AND MOVES IT EWD ACROSS THE OHIO VALLEY THIS WEEKEND. THE 48 HR TIME STEPS ON THE 20 KM NAM AND THE 80 KM NGM HAVE NO SUCH FEATURE. THUS IT SEEMS THAT THE GFS CONVECTIVE FEEDBACK PROBLEM HAS REARED ITS UGLY HEAD AGAIN. THUS THE SHORT RANGE GFS WAS MOSTLY TOSSED AND THE NAM/NGM WAS USED FOR INITIALIZATION. AS THE FRONT GETS PUSHED SWD POPS DECLINE INTO THE 20S OR LOWER FOR MOST OF THE LONG TERM FCST AS THE SFC RIDGE PUSHES FURTHER S AND DRIER AIR OCCUPIES THE MIDSTATE. MOS TEMPS WERE IN GENERAL GOOD AGREEMENT WITH ONE MORE DAY OF ABOVE NORMAL HIGH TEMPS. MOS POPS...DESPITE THE GFS SHORT RANGE PROBLEMS... SEEM TO BE FAIRLY REASONABLE AND INCREASE INTO THE LIKELY RANGE AS THE FRONT/TROUGH GETS CLOSER AND THEN DECLINE AFTERWARD. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ tn AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SALT LAKE CITY UT 850 PM MDT THU JUN 22 2006 .SYNOPSIS...A STRONG RIDGE OF HIGH PRESSURE WILL BUILD ACROSS THE GREAT BASIN THROUGH THE REMAINDER OF THE WEEK...AND REMAIN IN PLACE THROUGH THE WEEKEND. && .DISCUSSION...ELONGATED MID LEVEL RIDGE AXIS IN PLACE THIS EVENING...EXTENDING FROM THE DESERT SOUTHWEST THROUGH THE SOUTHERN GREAT BASIN AND CENTRAL CALIFORNIA. WEAK NORTHWEST FLOW ALOFT WITH A LIGHT NORTHERLY PRESSURE GRADIENT RESIDES ACROSS THE FORECAST AREA PER RUC/MSAS ANALYSIS. ADDITIONALLY...VERY DRY AIRMASS ASSOCIATED WITH THIS RIDGE REMAINS IN PLACE ACROSS THE GREAT BASIN/INTERMOUNTAIN WEST...WITH GOES-DERIVED PW VALUES BELOW .25 INCHES ACROSS MUCH OF THE AREA. WITH EXCEPTION OF FLAT CU WHICH DEVELOPED OVER SOUTHERN MOUNTAINS EARLIER...SKIES REMAINED CLEAR ACROSS THE REGION THIS EVENING. MID LEVEL RIDGE PROGGED TO STRENGTHEN ACROSS THE REGION...AND REMAIN CENTERED ACROSS SOUTHERN NV/CENTRAL CA THROUGH THE WEEKEND...RESULTING IN A WARMING TREND ACROSS THE REGION. TEMPS EXPECTED TO REACH THE MID 90S ALONG THE WASATCH FRONT OVER THE WEEKEND...WITH TEMPS IN UTAHS DIXIE APPROACHING THE 110 MARK. MOISTURE WILL GRADUALLY BECOME ENTRAINED WITHIN THE RIDGE NEXT WEEK...RESULTING IN AN INCREASING THREAT OF DIURNAL CONVECTION EACH AFTERNOON AND EVENING. && .AVIATION...NORMAL DIURNAL WIND SHIFTS EXPECTED AT KSLC THROUGH THE PERIOD...WITH SOUTHERLY DRAINAGE WIND DEVELOPING LATE THIS EVENING...AND LAKE BREEZE PASSAGE EARLY FRIDAY AFTERNOON. SEE SLCTAFSLC FOR DETAILS. && .FIRE WEATHER...HOT AND DRY WEATHER TO CONTINUE THROUGH THE WEEKEND WITH DIURNAL TERRAIN DRIVEN WINDS. ANY THUNDERSTORM ACTIVITY REMAINING ISOLATED THROUGH THE WEEKEND. && .SLC WATCHES/WARNINGS/ADVISORIES... UT...NONE. WY...NONE. && $$ SEAMAN ut AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LINCOLN IL 140 AM CDT FRI JUN 23 2006 .DISCUSSION... MAIN SHORT-TERM CONCERN WILL BE POPS TODAY...AS SLOW-MOVING FRONT DROPS SOUTH OF THE AREA. FURTHER OUT...NEXT ISSUE WILL BE APPROACHING NORTHERN STREAM SHORT-WAVE LATE IN THE WEEKEND INTO EARLY NEXT WEEK. 06Z SURFACE CHART SHOWS FRONTAL BOUNDARY STRETCHING ALONG THE I-70 CORRIDOR. TO THE NORTH OF THE FRONT...AIRMASS GRADUALLY DRIES OUT...WITH SIGNIFICANTLY LOWER DEWPOINTS NOTED ACROSS THE UPPER MIDWEST AND GREAT LAKES. ALOFT...ONE SHORT-WAVE IS CURRENTLY TRACKING ACROSS ILLINOIS...WHILE A SECOND WAVE IS EVIDENT IN WATER VAPOR IMAGERY ACROSS WESTERN KANSAS. SHORT TERM...TODAY THROUGH SUNDAY... FIRST ISSUE OF THE DAY WILL BE HOW TO HANDLE POPS AS FRONT MAKES VERY SLOW PROGRESS TO THE SOUTH. 00Z MODEL QPF FIELDS HAVE VERIFIED POORLY AT 06Z...WITH NAM-WRF/GFS/RUC ALL DEPICTING PRECIP AREA ACROSS MISSOURI THAT IS NOT THERE. MODELS SHIFT THIS PRECIP ACROSS THE SOUTHEAST KILX CWA THIS MORNING...THEN INTO INDIANA BY AFTERNOON. MODELS HAVE OBVIOUSLY MISSED THE MESOSCALE DETAILS...SO IT IS HARD TO TRUST THEIR PRECIP SOLUTIONS FOR THE REMAINDER OF THE DAY. HAVE THEREFORE OPTED TO SCALE BACK POPS CONSIDERABLY...WITH ONLY LOW POPS MENTIONED ALONG AND SOUTH OF I-70...MAINLY DURING THE MORNING. ONCE WAVE TRACKS EAST OF THE AREA...FRONT WILL GET A BETTER PUSH TO THE SOUTH AND ANY PRECIP THAT DEVELOPS ALONG IT WILL SHIFT INTO THE OHIO VALLEY BY LATER TODAY. MEANWHILE...HIGH PRESSURE WILL SETTLE INTO THE AREA TONIGHT INTO SATURDAY...BRINGING MOSTLY CLEAR...COOLER...AND LESS HUMID CONDITIONS. TRANQUIL WEATHER WILL BE SHORT-LIVED HOWEVER...AS A SIGNIFICANT SHORT-WAVE DROPS DOWN TOWARD ILLINOIS IN NORTHWEST UPPER FLOW PATTERN BY SATURDAY NIGHT/SUNDAY. MODELS HAVE BEEN INDICATING THIS FEATURE FOR SEVERAL RUNS NOW...ALTHOUGH THE 00Z SUITE SEEMS TO HAVE SPED THE SYSTEM UP JUST A BIT. NAM/GFS SUGGEST QPF COMING INTO AT LEAST THE WESTERN CWA AS EARLY AS SATURDAY NIGHT...WITH BETTER CHANCES FOR RAIN ARRIVING EVERYWHERE ON SUNDAY. THINK THIS SOLUTION MAY BE A LITTLE TOO FAST...ESPECIALLY GIVEN PRESENCE OF SURFACE RIDGING AND DRIER LOW-LEVEL PROFILES. WILL INCLUDE ONLY A 20 POP ACROSS LOCATIONS ALONG AND WEST OF I-55 SATURDAY NIGHT...BUT WILL BUMP UP TO 30S EVERYWHERE EXCEPT THE SE CWA ON SUNDAY. LONG TERM...MONDAY THROUGH THURSDAY... IN THE EXTENDED...MEAN TROUGHING PREVAILS ACROSS ILLINOIS EARLY NEXT WEEK...AS STRONG UPPER RIDGE OVER THE WESTERN ATLANTIC BLOCKS EASTWARD PROGRESSION OF SHORT-WAVE ENERGY. WITH POCKET OF COLD AIR ALOFT AND GOOD UPPER SUPPORT...DIURNAL CLOUDS/PRECIP WILL BE POSSIBLE ON MONDAY. HAVE BUMPED POPS TO 30 ACCORDINGLY. AFTER THAT...MADE VERY FEW CHANGES...AS CONFIDENCE IS LOW CONCERNING EXACTLY HOW FAST THE UPPER TROUGH WILL EJECT EASTWARD. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ BARNES il AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAND FORKS ND 230 AM CDT FRI JUN 23 2006 FORECAST CHALLENGE CONTINUES TO BE PCPN CHANCES IN WEAK SURFACE PATTERN ALONG WITH TEMPERATURES. MODELS AGAIN PRETTY SIMILAR WITH MAIN FEATURES AND WILL USE BLEND FOR FORECAST. REGION TO REMAIN IN MID LEVEL W-NW FLOW WITH A SERIES OF WEAK SHORTWAVES TO AFFECT FA THROUGH SATURDAY. WITH VERY WEAK SURFACE FORCING TOUGH TO PINPOINT FAVORED LOCATION FOR ANY PCPN TODAY. NEXT SHORT WAVE OVER NE MT TO CROSS FA TODAY. LEADING EDGE OF SHRA OVER NW ND AND SHOULD REACH NW FA JUST PRIOR TO 12Z. RUC INDICATING SUFFICIENT INSTABILITY AND CAPE BY 15Z FOR T AND WITH WEAK SURFACE PATTERN WILL SPREAD T CHANCES FROM W-E DURING MORNING. BETTER CHANCES THIS AFTERNOON AS CONVECTIVE TEMPERATURES REALIZED...ML CAPES APPROACH 1000J AND BULK SHEAR INCREASES. WITH WEAK SURFACE FORCING FEEL ANY SEVERE POTENTIAL TOO ISOLATED TO WARRANT ANY HIGHLIGHTS BUT CANT RULE OUT ISOLD HAILER. COLUMN WARMS SLIGHTLY AND WITH ATLEAST PARTIAL SOLAR TEMPERATURES SHOULD RECOVER TO AT OR A LITTLE ABOVE CONVECTIVE VALUES. WHAT TSRA THERE IS COULD CONTINUE INTO EVENING HOURS AS IN PAST SEVERAL DAYS. IN ADDITION EXPECT UPSTREAM CONVECTION TO DEVELOP THIS EVENING VCNTY HIGH PLAINS LOW PRESSURE AREA AND PROPAGATE EAST OVERNIGHT. FOR THIS WILL CONTINUE T CHANCES OVERNIGHT. WILL KEEP LOW POPS CONTINUING INTO SATURDAY AS MID LEVEL PATTERN CHANGES LITTLE AND WEAK SURFACE BOUNDARY PASS FA. IF MODEL TRENDS CONTINUE MAY BE ABLE TO PULL POPS FOR SATURDAY NIGHT AS BOUNDARY LOOKS TO BE EAST OF FA. FOR NOW WILL HOLD ON TO SLIGHT CHANCES TO AVOID ANY FLIP-FLOPPING OF POPS. HIGH PRESSURE BUILDS IN FOR REMAINDER OF WEEKEND FOR DRY WEATHER AND AVERAGE EARLY SUMMER TEMPERATURES. GFS AMPLIFYING WESTERN RIDGE REENFORCING NW FLOW OVER FA. TIMING OF WAVES THROUGH FLOW WILL BE MAIN CHALLENGE. WILL KEEP LONG RANGE DRY HOWEVER SOME HINTS AT PCPN POTENTIAL DURING NIGHT OVER FIRST HALF OF WORK WEEK. NO BIG CHANGES PLANNED TO LONG RAINGE. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ VOELKER nd AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON OH 355 AM EDT FRI JUN 23 2006 .SHORT TERM /TODAY THROUGH SUNDAY/... SURFACE ANALYSIS SHOWS COLD FRONT FROM LAKE ERIE TO JUST SOUTH OF KSTL. REGIONAL RADARS SHOW BEST CONVECTION OVER EASTERN KENTUCKY. UPPER TROF WILL PROGRESS EAST TODAY...WHICH WILL FINALLY TAKE THE PESKY COLD FRONT TO OUR EAST BY THIS EVENING. CONTEMPLATED A FLOOD WATCH FOR SOUTHEAST 1/2 OF FA. HOWEVER...SOUTHEAST OF I-71 HAS NOT SEEN THE RAIN THE PAST COUPLE OF DAYS AS THOSE OF NORTHWEST OF I-71 HAVE. THERE ARE A FEW EXCEPTIONS EAST OF COLUMBUS AND SOUTHWEST OF CINCINNATI...BUT THESE ARE MORE LOCALIZED PROBLEMS. ALSO PWS ARE ONLY A 150% OF NORMAL. NOT EXPECTING ATMOSPHERE TO MIX OUT MUCH OVER FORECAST AREA. THIS WILL KEEP BOUNDARY LAYER INSTABILITY AROUND 1000 J/KG AND THUS KEEP REALLY DEEP CONVECTION FROM OCCURRING. NEXT SHIFT WILL NEED TO MONITOR CONVECTIVE TRENDS TO SEE IF A MESOSCALE FLOOD WATCH WILL BE NEEDED. AS FOR THE REST OF THE FORECAST...SURFACE HIGH WILL BUILD IN FOR SATURDAY. HOWEVER AN UPPER LOW SWING INTO THE WESTERN GREAT LAKES. BOTH THE NAM AND GFS BRING BACK LOW LEVEL MOISTURE FROM THE EAST AS INVERTED SURFACE TROF SETS UP OVER FORECAST AREA. NAM SUGGESTING AFTERNOON BLYR INSTABILITY OF 1000 TO 1500 J/KG...THUS A FEW THUNDERSTORMS WILL BE POSSIBLE SUNDAY AFTERNOON. MAV TEMPS LOOK PRETTY GOOD WILL ONLY TWEAK. TIPTON && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... NO CHANGES WERE MADE TO THE EXTENDED. FOR THOUGHTS OF PREVIOUS FORECASTER SEE DISCUSSION BELOW. TIPTON && .AVIATION /06Z-06Z/... FRNTL BNDRY REMAINS JUST NORTH AND WEST OF FCST AREA THIS MRNG. MID LVL S/WV MOVING THRU REGION ATTM AND AIDING IN CONVECTIVE DVLPMNT. HOWEVER...ATMOSPHERE ACRS REGION HAS BEEN WORKED OVER QUITE A BIT SINCE LATE AFTN...AND RESULT HAS BEEN A GENERAL DECREASE OVER LAST HOUR OR TWO IN PCPN COVERAGE AND INTENSITY. STRONGER TSRA REMAIN TO SOUTH ACRS CNTRL/SRN KY WHERE BETTER INSTABILITY EXISTS. WHILE CHANCE FOR TSRA HAS DIMINISHED FOR REST OF THE NIGHT...WILL CONTINUE TO SEE WAVES OF -SHRA MOVE ACRS TAFS. NEXT BATCH OF PCPN MOVING NE ACRS SRN INDIANA AND NRN KY IN ASSOC WITH ANOTHER MID LVL VORT. AS THIS FEATURE APPCHS FCST AREA... CURRENT RUC INDCG NICE AXIS OF SFC/BNDRY LYR CONV TO SET UP BY DAYBREAK JUST AHEAD OF FRNTL BNDRY. LO LVL CONV THEN HOLDS ACRS REGION THROUGHOUT DAYTIME HOURS AS SFC LO TRACKS ACRS REGION WITH MAIN MID LVL S/WV. BEST INSTABILITY WILL EXIST ALONG AND EAST OF I-71 AS FRNTL BNDRY SLOWLY SLIPS TO SOUTH AND EAST. RUC/NAM ALSO BOTH INDCG MID LVL DEFORMATION AXIS WILL DROP SE IN TANDEM WITH FRNTL BNDRY...AND ALONG WITH OTHER PARAEMTERS MENTIONED WILL AID IN PCPN COVERAGE. HAVE INDICATED A 6-8 HOUR PERIOD OF PREVAILING SHRA AT ALL TAF SITES FROM MID MRNG THRU AFTN HOURS. ADDED A TEMPO GROUP FOR THUNDER AHEAD OF MID LVL S/WV. PCPN WILL COME TO AN END AT KDAY/KCMH/KLCK BY LATE AFTN WITH DRIER NRLY FLO DVLPG. FURTHER SOUTH...FRNTL BNDRY WILL DROP SOUTH OF KCVG/KLUK BY ERLY EVNG BUT REMAIN CLOSE ENUF TO MAINTAIN VCSH THRU END OF FCST PERIOD. LKLY TO SEE SOME FOG DVLP LATE FRI NIGHT...AND WILL ADDRESS IN GREATER DETAIL WITH 12Z TAFS. RYAN && .PREV DISCUSSION... /ISSUED 607 PM EDT THU JUN 22 2006/ LONG TERM /SATURDAY THROUGH THURSDAY/... THE MODELS ARE IN GENERAL AGREEMENT WITH PCPN MAINLY CONFINED TO SE OHIO AND NE KY AT 12Z SATURDAY BEHIND A SFC LOW MOVING ALONG A FRONTAL BNDRY. DRIER AND MORE SEASONABLE AIR WORKS IN WITH NORTHERLY FLOW FOR SATURDAY AND PERSISTS THROUGH THE REMAINDER OF EXTENDED FOR THE MOST PART. IT APPEARS THAT THE BNDRY WILL STALL ALONG THE EAST COAST FOR THE MAJORITY OF THE EXTENDED FCST. SEVERAL DISTURBANCES WILL MOVE NORTH ALONG THE BNDRY...AND THE SE FCST AREA MAY BE BRUSHED AT TIMES BY THESE IMPULSES THROUGH WEDNESDAY. AT THIS POINT...LOW CHANCE POPS APPEAR ALL THAT IS WARRANTED. ALTHOUGH THERE IS OBVIOUSLY GREAT UNCERTAINTY...A LOW PRESSURE SYSTEM MOVES ACROSS THE OHIO VALLEY THURSDAY. TEMPERATURES ARE EXPECTED TO BE NEAR NORMAL LEVELS THROUGH THE ENTIRE EXTENDED. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ oh AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON OH 143 AM EDT FRI JUN 23 2006 .AVIATION /06Z-06Z/... FRNTL BNDRY REMAINS JUST NORTH AND WEST OF FCST AREA THIS MRNG. MID LVL S/WV MOVING THRU REGION ATTM AND AIDING IN CONVECTIVE DVLPMNT. HOWEVER...ATMOSPHERE ACRS REGION HAS BEEN WORKED OVER QUITE A BIT SINCE LATE AFTN...AND RESULT HAS BEEN A GENERAL DECREASE OVER LAST HOUR OR TWO IN PCPN COVERAGE AND INTENSITY. STRONGER TSRA REMAIN TO SOUTH ACRS CNTRL/SRN KY WHERE BETTER INSTABILITY EXISTS. WHILE CHANCE FOR TSRA HAS DIMINISHED FOR REST OF THE NIGHT...WILL CONTINUE TO SEE WAVES OF -SHRA MOVE ACRS TAFS. NEXT BATCH OF PCPN MOVING NE ACRS SRN INDIANA AND NRN KY IN ASSOC WITH ANOTHER MID LVL VORT. AS THIS FEATURE APPCHS FCST AREA... CURRENT RUC INDCG NICE AXIS OF SFC/BNDRY LYR CONV TO SET UP BY DAYBREAK JUST AHEAD OF FRNTL BNDRY. LO LVL CONV THEN HOLDS ACRS REGION THROUGHOUT DAYTIME HOURS AS SFC LO TRACKS ACRS REGION WITH MAIN MID LVL S/WV. BEST INSTABILITY WILL EXIST ALONG AND EAST OF I-71 AS FRNTL BNDRY SLOWLY SLIPS TO SOUTH AND EAST. RUC/NAM ALSO BOTH INDCG MID LVL DEFORMATION AXIS WILL DROP SE IN TANDEM WITH FRNTL BNDRY...AND ALONG WITH OTHER PARAEMTERS MENTIONED WILL AID IN PCPN COVERAGE. HAVE INDICATED A 6-8 HOUR PERIOD OF PREVAILING SHRA AT ALL TAF SITES FROM MID MRNG THRU AFTN HOURS. ADDED A TEMPO GROUP FOR THUNDER AHEAD OF MID LVL S/WV. PCPN WILL COME TO AN END AT KDAY/KCMH/KLCK BY LATE AFTN WITH DRIER NRLY FLO DVLPG. FURTHER SOUTH...FRNTL BNDRY WILL DROP SOUTH OF KCVG/KLUK BY ERLY EVNG BUT REMAIN CLOSE ENUF TO MAINTAIN VCSH THRU END OF FCST PERIOD. LKLY TO SEE SOME FOG DVLP LATE FRI NIGHT...AND WILL ADDRESS IN GREATER DETAIL WITH 12Z TAFS. RYAN && .PREV DISCUSSION... /ISSUED 952 PM EDT THU JUN 22 2006/ SHORT TERM /TONIGHT/... UPDATING TO DROP SEVERE THUNDERSTORM WATCH. ALSO ADJUSTING POPS WITH SHOWERS RETURNING FROM THE SOUTHWEST. PREV DISCUSSION... /ISSUED 607 PM EDT THU JUN 22 2006/ SHORT TERM /TONIGHT/... UPDATED ZONES TO CLEAR PART OF WATCH AND TO REMOVE HEAT ADVISORY HEADLINES. SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/... HOT AND HUMID SURFACE AIRMASS AND COOLING AIR ALOFT HAVE COMBINED TO PRODUCE STRONG INSTABILITY LATE THIS AFTERNOON AND THIS EVENING. APPROACHING COLD FRONT IS PROVIDING ADDITIONAL LIFT. AS A RESULT...SEVERE THUNDERSTORM WATCH IS IN EFFECT...AND WARNINGS ARE BEING ISSUED. FOR THIS EVENING...HAVE INCREASED POPS TO CATEGORICAL NORTH AND LIKELY SOUTH. EXPECT THUNDERSTORMS TO DECREASE IN COVERAGE AND INTENSITY LATE TONIGHT AS INSTABILITY LESSENS. INCREASED POPS FOR FRIDAY AND FRIDAY NIGHT WITH MODELS INDICATING A STRONG WAVE OF LOW PRESSURE ROLLING UP THE FRONT AFTER IT DROPS JUST SOUTH OF THE OHIO RIVER. MADE MINOR ADJUSTMENTS TO TEMPERATURE FORECAST. HIGHS ON FRIDAY WILL BE SIGNIFICANTLY COOLER IN THE EASTERLY FLOW BEHIND THE COLD FRONT. LONG TERM /SATURDAY THROUGH THURSDAY/... THE MODELS ARE IN GENERAL AGREEMENT WITH PCPN MAINLY CONFINED TO SE OHIO AND NE KY AT 12Z SATURDAY BEHIND A SFC LOW MOVING ALONG A FRONTAL BNDRY. DRIER AND MORE SEASONABLE AIR WORKS IN WITH NORTHERLY FLOW FOR SATURDAY AND PERSISTS THROUGH THE REMAINDER OF EXTENDED FOR THE MOST PART. IT APPEARS THAT THE BNDRY WILL STALL ALONG THE EAST COAST FOR THE MAJORITY OF THE EXTENDED FCST. SEVERAL DISTURBANCES WILL MOVE NORTH ALONG THE BNDRY...AND THE SE FCST AREA MAY BE BRUSHED AT TIMES BY THESE IMPULSES THROUGH WEDNESDAY. AT THIS POINT...LOW CHANCE POPS APPEAR ALL THAT IS WARRANTED. ALTHOUGH THERE IS OBVIOUSLY GREAT UNCERTAINTY...A LOW PRESSURE SYSTEM MOVES ACROSS THE OHIO VALLEY THURSDAY. TEMPERATURES ARE EXPECTED TO BE NEAR NORMAL LEVELS THROUGH THE ENTIRE EXTENDED. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ oh AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LINCOLN IL 1045 AM CDT FRI JUN 23 2006 .UPDATE... SCATTERED SHOWERS WHICH HAD AFFECTED THE SOUTHEAST EARLIER THIS MORNING HAVE ALL BUT CLEARED THE AREA AS COLD FRONT HAS FINALLY SHIFTED SOUTH OF I-70. HOWEVER... SFC MESOANALYSIS AND VISIBLE SATELLITE IMAGERY BOTH INDICATE A WEAK BOUNDARY STRUNG OUT ROUGHLY FROM KIKK-KBMI-KSPI. THERE APPEARS TO BE A SUBTLE WIND SHIFT AND WEAK CONVERGENCE ALONG THIS BOUNDARY... ALONG WITH A DEWPOINT DISCONTINUITY. THERE HAS BEEN AN ISOLATED CONVECTIVE SHOWER OVER LIVINGSTON COUNTY... NORTH OF OUR CWA THIS MORNING. JUST RECENTLY SATELLITE IMAGERY... AND OLD FASHIONED HUMAN EYE OBSERVATIONS INDICATE SOME DECENT TCU SOUTHEAST OF KILX... OVER MACON COUNTY. ATMOSPHERE OUT AHEAD OF THIS BOUNDARY REMAINS FAIRLY MOIST AND UNSTABLE... WHILE FARTHER NORTHWEST HIGH PRESSURE WILL DOMINATE THIS AFTERNOON... BRINGING WITH IT MID-LEVEL DRY AIR AND CAPPING AS PER 12Z KDVN SOUNDING. FOR NOW... WILL MENTION AN ISOLATED POP ALONG AND SOUTHEAST OF OUR WEAK BOUNDARY... AND KEEP THE 20S GOING IN THE FAR SOUTHEAST WHERE CU IS BUILDING UP IN VICINITY OF OUR OLD STALLED OUT FRONT. && .PREV DISCUSSION... /ISSUED 140 AM CDT FRI JUN 23 2006/ MAIN SHORT-TERM CONCERN WILL BE POPS TODAY...AS SLOW-MOVING FRONT DROPS SOUTH OF THE AREA. FURTHER OUT...NEXT ISSUE WILL BE APPROACHING NORTHERN STREAM SHORT-WAVE LATE IN THE WEEKEND INTO EARLY NEXT WEEK. 06Z SURFACE CHART SHOWS FRONTAL BOUNDARY STRETCHING ALONG THE I-70 CORRIDOR. TO THE NORTH OF THE FRONT...AIRMASS GRADUALLY DRIES OUT...WITH SIGNIFICANTLY LOWER DEWPOINTS NOTED ACROSS THE UPPER MIDWEST AND GREAT LAKES. ALOFT...ONE SHORT-WAVE IS CURRENTLY TRACKING ACROSS ILLINOIS...WHILE A SECOND WAVE IS EVIDENT IN WATER VAPOR IMAGERY ACROSS WESTERN KANSAS. SHORT TERM...TODAY THROUGH SUNDAY... FIRST ISSUE OF THE DAY WILL BE HOW TO HANDLE POPS AS FRONT MAKES VERY SLOW PROGRESS TO THE SOUTH. 00Z MODEL QPF FIELDS HAVE VERIFIED POORLY AT 06Z...WITH NAM-WRF/GFS/RUC ALL DEPICTING PRECIP AREA ACROSS MISSOURI THAT IS NOT THERE. MODELS SHIFT THIS PRECIP ACROSS THE SOUTHEAST KILX CWA THIS MORNING...THEN INTO INDIANA BY AFTERNOON. MODELS HAVE OBVIOUSLY MISSED THE MESOSCALE DETAILS...SO IT IS HARD TO TRUST THEIR PRECIP SOLUTIONS FOR THE REMAINDER OF THE DAY. HAVE THEREFORE OPTED TO SCALE BACK POPS CONSIDERABLY...WITH ONLY LOW POPS MENTIONED ALONG AND SOUTH OF I-70...MAINLY DURING THE MORNING. ONCE WAVE TRACKS EAST OF THE AREA...FRONT WILL GET A BETTER PUSH TO THE SOUTH AND ANY PRECIP THAT DEVELOPS ALONG IT WILL SHIFT INTO THE OHIO VALLEY BY LATER TODAY. MEANWHILE...HIGH PRESSURE WILL SETTLE INTO THE AREA TONIGHT INTO SATURDAY...BRINGING MOSTLY CLEAR...COOLER...AND LESS HUMID CONDITIONS. TRANQUIL WEATHER WILL BE SHORT-LIVED HOWEVER...AS A SIGNIFICANT SHORT-WAVE DROPS DOWN TOWARD ILLINOIS IN NORTHWEST UPPER FLOW PATTERN BY SATURDAY NIGHT/SUNDAY. MODELS HAVE BEEN INDICATING THIS FEATURE FOR SEVERAL RUNS NOW...ALTHOUGH THE 00Z SUITE SEEMS TO HAVE SPED THE SYSTEM UP JUST A BIT. NAM/GFS SUGGEST QPF COMING INTO AT LEAST THE WESTERN CWA AS EARLY AS SATURDAY NIGHT...WITH BETTER CHANCES FOR RAIN ARRIVING EVERYWHERE ON SUNDAY. THINK THIS SOLUTION MAY BE A LITTLE TOO FAST...ESPECIALLY GIVEN PRESENCE OF SURFACE RIDGING AND DRIER LOW-LEVEL PROFILES. WILL INCLUDE ONLY A 20 POP ACROSS LOCATIONS ALONG AND WEST OF I-55 SATURDAY NIGHT...BUT WILL BUMP UP TO 30S EVERYWHERE EXCEPT THE SE CWA ON SUNDAY. LONG TERM...MONDAY THROUGH THURSDAY... IN THE EXTENDED...MEAN TROUGHING PREVAILS ACROSS ILLINOIS EARLY NEXT WEEK...AS STRONG UPPER RIDGE OVER THE WESTERN ATLANTIC BLOCKS EASTWARD PROGRESSION OF SHORT-WAVE ENERGY. WITH POCKET OF COLD AIR ALOFT AND GOOD UPPER SUPPORT...DIURNAL CLOUDS/PRECIP WILL BE POSSIBLE ON MONDAY. HAVE BUMPED POPS TO 30 ACCORDINGLY. AFTER THAT...MADE VERY FEW CHANGES...AS CONFIDENCE IS LOW CONCERNING EXACTLY HOW FAST THE UPPER TROUGH WILL EJECT EASTWARD. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ HARDIMAN/BARNES il AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 1130 AM EDT FRI JUN 23 2006 .UPDATE... MAIN FCST CONCERN IS SHRA/TSRA POTENTIAL WEST. WV IMAGERY AND RUC ANALYSIS INDICATED AN UPSTREAM SHRTWV FROM SRN MANITOBA INTO THE CNTRL DAKOTAS WITH SCT ELEVATED TSRA AHEAD OF THIS FEATURE INTO NE ND AND NW MN IN AREA OF FAVORABLE 300K-305K ISENTROPIC LIFT. EXTRAPOLATION OF RADAR/SATELLITE TRENDS AND 12Z RUC/NAM SUGGEST THAT ANY SHRA/TSRA WOULD MOVE INTO THE WRN CWA AFT 22Z...AS IN THE GOING FCST. MODIFIED FCST AND OBSERVED SNDGS WITH WORST CASE TEMP/DEWPOINT OF 75/50 INTO W UPR MI ONLY GIVE SBCAPE VALUES OF AROUND 500 J/KG. EXPECT AFTERNOON MIXING MAY KEEP DEWPOINTS EVEN LOWER. SO...NO SHRA/TSRA DEVELOPMENT EXPECTED AHEAD UNTIL ARRIVAL OF THE DAKOTAS SHRTWV WITH STEEPER MID LVL LAPSE RATES AND INCREASING 300K-305K ISENTROPIC LIFT. OTHERWISE...AN AREA OF MID CLOUDS...WITH ONLY SCT SPRINKLES OR VIRGA N OF KMQT...WAS MOVING THROUGH N CNTRL UPR MI SUPPORTED BY A WEAK 700 MB TROF. WITH A VERY DRY LYR BLO 700 MB PER KGRB/KAPX SNDGS...NO PCPN IS EXPECTED INTO UPR MI. && .PREV DISCUSSION...ISSUED 449 AM EDT FRI JUN 23 2006. UPPER AIR PATTERN CONSISTS OF A 500 MB RIDGE ACROSS THE DESERT SW AND ACROSS THE SOUTHERN U.S. WITH TROUGHING ACROSS CENTRAL AND EASTERN CANADA DOWN INTO THE OHIO VALLEY AND APPALACHIANS AND A CLOSED LOW EAST OF HUDSON BAY ACROSS NORTHERN QUEBEC. UPPER FLOW IS NW AND THIS PATTERN SEEMS SIMILAR TO A WINTER PATTERN ALMOST. NUMEROUS SHORTWAVES ARE EMBEDDED IN THIS FLOW WITH ONE SEVERAL ACROSS THE CENTRAL PLAINS KICKING OFF CONVECTION THIS EVENING. THERE IS A SHORTWAVE ACROSS NORTHERN MN THAT SHOWS UP ON WATER VAPOR AS A DARKENING AND CYCLONIC CIRCULATION AND ONE OVER SOUTHERN ALBERTA AMD SOUTHERN SASKATCHEWAN. THE SHORTWAVE ACROSS ALBERTA AND SASKATCHEWAN HAS A MOTTLED APPEARANCE TO IT WITH SOME CONVECTION WITH IT AND THIS WILL BE THE NEXT WEATHER MAKER AS THE SHORTWAVE IN MN APPEARS TO TRACK ACROSS THE AREA...BUT DOES NOT APPEAR TO DO MUCH. WRF MODEL SHOWS NOTHING WITH THE MN SHORTWAVE...BUT APPEARS TO GENERATE SOME QPF WITH THE ALBERTA...SASK SHORTWAVE. WRF SHOWS A CLOSED LOW FORMING BY 12Z SUN OVER SE MN AND THEN SLOWLY MOVES THE CLOSED LOW SOUTH INTO CENTRAL IL BY 12Z MON. WRF SHOWS SOME WEAK 850-500 MB Q-VECTOR CONVERGENCE MOVING THROUGH THE CWA TODAY AND TONIGHT...BUT DEEP MOISTURE IS LACKING. AS THE CLOSED LOW FORMS...850-500 MB Q-VECTOR CONVERGENCE STRENGTHENS AND DEEP MOISTURE INCREASES...BUT THIS IS MOSTLY SOUTH OF THE AREA WITH THE SOUTHERN CWA ON THE NORTHER PERIPHERY OF THIS SYSTEM. WRF ALSO SHOWS SOME WEAK ISENTROPIC LIFT IN THE MID LEVELS ABOVE 750 MB ON I300K SURFACE...BUT LOWER LEVELS REMAIN DRY EVEN WITH SOME LIFT. GFS SHOWS SIMILAR SCENARIO. WILL GO WITH THIS SCENARIO WITH SOME LIFT IN MID LEVELS...BUT DRY LOW LEVELS AND ALL THIS WOULD DO IS PRODUCE SOME VIRGA AND AT WORST A FEW SPRINKLES MAYBE. WILL GO DRY FOR NOW FOR TODAY THOUGH AND CONTINUE WITH THIS IN THE FORECAST. TONIGHT IS A DIFFERENT STORY AND WILL INTRODUCE SLIGHT CHANCE POPS AS BOTH GFS AND WRF PUT OUT SOME QPF AND HAVE POPS FIRST IN THE WEST HALF AND THEN AFTER MIDNIGHT IN THE EAST HALF. 850-500 MB Q-VECTOR CONVERGENCE IS STRONGER TONIGHT WITH SLIGHTLY DEEPER MOISTURE IN THE MID LEVELS AND DRY AIR WILL BE ERODED SOMEWHAT WITH COOLING TAKING PLACE AND SLIGHTLY DEEPER MOISTURE. WRF AND GFS BOTH SHOW UNSTABLE AIR IN THE EVENING IN THE MID LEVELS...SO WILL HAVE THUNDERSTORMS IN THROUGH MIDNIGHT ACROSS THE WEST HALF. THE Q-VECTOR CONVERGENCE WEAKENS LATE TONIGHT...SO WILL GO DRY FOR SAT MORNING. CHANCE POPS SATURDAY AFTERNOON THROUGH SUNDAY EVENING LOOK GOOD ACROSS THE WEST AND SOUTH AS UNSTABLE AIR RETURNS AND THE 500 MB LOW AND TROUGH SET UP. TEMPERATURES ALSO LOOK GOOD AND MADE A FEW TWEAKS HERE AND THERE...BUT NOTHING REAL DRASTIC. OVERALL...DID NOT MAKE MANY CHANGES TO THE GOING FORECAST. && .MQT...WATCHES/WARNINGS/ADVISORIES...NONE. && $$ JLB(UPDATE) MICHELS(PREV DISC) mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 1121 AM EDT FRI JUN 23 2006 .UPDATE... EARLY MORNING STATUS HAS BEEN HANGING TOUGH ACROSS WEST-CENTRAL CWA...WITH THE NORTHERN EDGE STARTING TO MIX OUT. WILL UPDATE TO CARRY CLOUDS LONGER ACROSS THE NORTH...BUT STILL EXPECT THE CU/SC TO MIX OUT AS MUCH DRIER AIR ADVECTS IN ABOVE THE INVERSION. 12Z DTX/13Z TAMDAR SOUNDINGS SHOW A FAIR AMOUNT OF LOW-LEVEL MOISTURE ACROSS THE SOUTH...WITH 12Z RUC/NAM STILL TRYING TO GENERATE A COUPLE HUNDREDTHS QPF THIS AFTERNOON. 12Z RUC FORECAST SOUNDINGS SHOW THE LOW-LEVEL LEVELS SATURATING WITH STEEP LOW-LEVEL LAPSE RATES...BUT WITH CU FIELD CURRENT SUPPRESSED BY HIGHER CLOUDS AND A STRONGER INVERSION WILL STICK WITH THE DRY FORECAST. TWEAKED TEMPERATURES A BIT GIVEN THE MORE PERSISTENT CLOUD COVER ACROSS NORTHWESTERN CWA...IN ADDITION NORTH/NORTHEASTERLY FLOW OFF LAKE HURON. && .AVIATION...721 AM EDT FRI JUN 23 2006 THE EXTENSIVE HIGH LEVEL CLOUDINESS ASSOCIATED WITH THE FRONTAL BOUNDARY DRAPED ACROSS THE OHIO VALLEY CLEARED THE SAGINAW VALLEY AND THUMB REGION EARLY THIS MORNING. THIS ALLOWED MVFR CEILINGS IN STRATUS TO DEVELOP UNDERNEATH THE INVERSION. THIS STRATUS HAS AFFECTED BOTH MBS AND FNT. DAYTIME HEATING WILL ALLOW MIXING TO TAP INTO THE VERY DRY AIR ABOVE THE INVERSION...WHICH SHOULD ALLOW THE STRATUS TO MIX OUT INTO A SCATTERED CU FIELD BY AFTERNOON. BKN TO OVC CEILINGS ABOVE 10K FT HAVE PREVENTED THE STRATUS FROM DEVELOPING AROUND DETROIT. BASED ON SATELLITE DATA...EXPECT THESE HIGH BASED CLOUDS TO BE RATHER PERSISTENT AROUND DETROIT THIS MORNING. FOR THIS REASON...THINK THIS WILL KEEP ANY DIURNAL CU THAT IS ABLE TO DEVELOP THIS MORNING MORE SCATTERED IN NATURE IN THE DETROIT AREA. HIGH PRESSURE WILL GRADUALLY MOVE ACROSS THE NORTHERN GREAT LAKES TODAY. EXPECT NORTH TO NORTHEASTERLY SURFACE WINDS WILL REMAIN AROUND 10 KNOTS THROUGHOUT THE AFTERNOON. THE WINDS WILL BECOME LIGHT BETWEEN 01Z AND 03Z AS HIGH PRESSURE BUILDS IN FROM THE NORTH AND WITH THE LOSS OF DAYTIME HEATING. && .PREV DISCUSSION...ISSUED 337 AM EDT FRI JUN 23 2006 SHORT TERM...TODAY AND TONIGHT THE 07Z SURFACE ANALYSIS SHOWS HIGH PRESSURE CENTERED OVER THE WESTERN UP WITH THE PRIMARY SURFACE COLD FRONT EXTENDING FROM THE MID MISSISSIPPI VALLEY TO WESTERN NEW YORK STATE. A SECONDARY COLD FRONT...MARKING THE LEADING EDGE OF MUCH DRYER LOW LEVEL AIR...IS LOCATED OVER THE DETROIT AREA. THE CURRENT WATER VAPOR LOOP AND 00Z UPPER AIR PLOTS SHOW AN UPPER LOW OVER FAR NORTHERN QUEBEC WITH MORE ZONAL FLOW ACROSS THE NORTHERN CONUS. ALSO SHOWN ON THE WATER VAPOR LOOP IS A POCKET OF DRY MID LEVEL AIR LOCATED OVER THE NORTHERN AND WESTERN GREAT LAKES REGION...IN THE VICINITY OF THE SURFACE HIGH PRESSURE. THE UPPER LOW OVER NORTHERN QUEBEC IS EXPECTED TO DEEPEN SLIGHTLY TODAY AND RESULT IN SOME MINOR MID LEVEL HEIGHT FALLS ACROSS THE STATE...ALLOWING THE MID LEVEL WIND FIELD TO VEER MORE WEST-NORTHWESTERLY. THIS WILL ALLOW THE SURFACE HIGH PRESSURE TO BUILD INTO THE LOWER PENINSULA TODAY. NORTH-NORTHEASTERLY LOW LEVEL FLOW AROUND THIS HIGH WILL HELP ADVECT MUCH DRYER AIR INTO SE MICHIGAN. SURFACE DEWPOINTS UPSTREAM ARE ACTUALLY IN THE 40S. AS OF 07Z...THERE IS A SOLID OVERCAST OF MID AND HIGH CLOUDS ACROSS SE MICHIGAN. ENTRANCE REGION OF A SEASONALLY STRONG UPPER LEVEL JET ACROSS EASTERN CANADA APPEARS TO HAVE LED TO THE INCREASE IN HIGH CLOUDS. THIS FORCING AND HIGH LEVEL MOISTURE WILL SLOWLY PUSH SOUTHEAST DURING THE COURSE OF THE DAY. SHALLOW LOW LEVEL COLD AIR ADVECTION WILL ALLOW SOME SCATTERED TO OVERCAST STRATUS/STRATO CU TO DEVELOP THIS MORNING. THIS WILL BE MORE LIKELY ACROSS THE SAGINAW VALLEY AND THUMB WHERE NORTHEASTERLY FLOW OFF LAKE HURON WILL ADD SOME MOISTURE TO THE BOUNDARY LAYER AND WHERE THE LOW LEVEL INVERSION WILL BE STRONGER. INTERESTING TO NOTE THAT THE GFS AND WRFHEMI SOLUTIONS SHOW A COUPLE HUNDREDTHS OF QPF ACROSS LENAWEE AND MONROE COUNTIES TODAY ALONG THE 700MB FRONTAL BOUNDARY. SINCE CONVECTION ACROSS THE OHIO VALLEY HAS PUSHED WELL SOUTH OF WHERE THE GFS SOLUTION WOULD INDICATE AND GIVEN THE AMOUNT OF STABILITY OVER THE STATE...PREFER THE NAM SOLUTION WHICH KEEPS MEASURABLE PRECIP JUST SOUTH OF THE STATE TODAY. THE POTENTIAL FOR LIGHT SHOWERS SOUTH OF THE I-94 CORRIDOR WILL STILL HAVE TO BE MONITORED THROUGHOUT THE DAY THOUGH. THE NAM SOLUTION BECOMES QUITE ROBUST WITH THE AMOUNT OF LOW LEVEL MOISTURE THIS MORNING. THUS...ITS SOLUTION INDICATES THAT IT WILL TAKE WELL INTO THE AFTERNOON FOR THE LOWER CLOUDS TO MIX OUT. SINCE THE NAM INITIALIZED SIGNIFICANTLY TOO MOIST BELOW 800MB BASED ON THE 00Z KAPX AND KGRB SOUNDINGS...THINK ANY LOW CLOUDS THAT ARE ABLE TO DEVELOP THIS MORNING WILL MIX OUT RATHER QUICKLY BY EARLY AFTERNOON...EXCEPT FOR PERHAPS ALONG THE IMMEDIATE LAKE HURON SHORELINE. THERE SHOULD BE ENOUGH INSOLATION THROUGH THE HIGHER CLOUDS TO SIDE WITH THE HIGHER MAV MOS GUIDANCE VALUES OF MID 70S INLAND TO UPPER60S/LOWER 70S NEAR LAKE HURON. OPTIMAL RADIATIONAL COOLING CONDITIONS ARE EXPECTED TONIGHT WITH THE SURFACE HIGH OVERHEAD ALONG WITH THE CLEAR SKIES AND MUCH LOWER SURFACE DEWPOINTS. SEE NO REASON TO DEVIATE MUCH FROM GUIDANCE WHICH DROPS MINS INTO THE MID TO UPPER 40S ACROSS THE NORTH HALF OF THE FORECAST AREA. LONG TERM...SATURDAY THROUGH FRIDAY IT SEEMS WE WILL TRANSITION TOWARD WEST COAST RIDGE AND GREAT LAKES TROUGH THROUGH THE UPCOMING LONG TERM OF THIS FORECAST WHICH WILL PROVIDE OUR CHANCES FOR MORE RAIN. A FAIRLY ZONAL FLOW ACROSS NOAM WITH A NOTABLE SHEAR AXIS FROM ALBERTA INTO SASKATCHEWAN AS HUDSON BAY LOW ROTATES IN A QUASI-STATIONARY POSITION. AS ADDITIONAL SHORT WAVE ENERGY UNDERCUTS THIS SHEAR AXIS...THE WEST COAST RIDGE WILL BEGIN TO AMPLIFY AND IN TURN ALLOW THIS WAVE TO DIVE SOUTHEAST AND EVENTUALLY DEVELOP A CUT OFF UPPER LOW WHICH GFS/ECMWF SUGGEST WILL OCCUR IN THE VICINITY OF NORTHERN ILLINOIS MONDAY-TUESDAY TIME FRAME. THEN WE FIND OURSELVES WITHIN A NORTHWEST FLOW REGIME WHICH COULD PROVE TO BE INTERESTING AS BAROCLINICITY WILL BE INCREASING SOMEWHERE ACROSS THE NORTHERN 1/3RD OF THE COUNTRY WITH NOCTURNAL LOW LEVEL JET LIKELY DEVELOPING CONVECTION NEAR AND NORTH OF THIS BOUNDARY. SATURDAY LOOKS TO BE A GOOD START TO THIS WEEKEND AS UPSTREAM SHORT WAVE APPROACHES THE NORTHERN PLAINS INTO THE UPPER MISSISSIPPI RIVER VALLEY. AT THE SURFACE...HIGH PRESSURE REMAINS IN CONTROL BUT AS CONVECTION DEVELOPS IN RESPONSE TO THIS APPROACHING SHORT WAVE...CLOUD DEBRIS WILL BE INCREASING ACROSS THE CWA. DESPITE THAT OUR TEMPERATURES WILL GENERALLY FALL INTO THE UPPER 70S BASED ON 850MB TEMPS AOA 12C. THE EXCEPTION TO THIS WILL BE NEAR LAKE HURON AS LAKE BREEZE DEVELOPMENT AND/OR LIGHT ONSHORE FLOW AROUND THE PERIPHERY OF THIS SURFACE HIGH WILL KEEP TEMPS A BIT COOLER...LOWER 70S. AT THIS TIME WE WILL KEEP SATURDAY NIGHT DRY ALTHOUGH WE DO EXPECT PLENTY OF CLOUD COVER INCREASING FROM WEST TO EAST. NUMERICAL SUITE OFFERS A VARIETY OF IDEAS WITH GFS SUGGESTING CONVECTIVE COMPLEX APPROACHING THE WESTERN PORTIONS OF OUR CWA OVERNIGHT WITH THE NMM MORE COMPACT AND FURTHER WEST. ECMWF IS EVEN SLOWER HENCE OUR DRY FORECAST WITH TEMPERATURES DROPPING INTO THE MIDDLE 50S. ON SUNDAY THE UPPER LOW WILL BE DEVELOPING UPSTREAM FROM US WHILE DOWNSTREAM MOISTURE TRANSPORT INCREASING. THIS PLACES OUR REGION SANDWICHED WITH THICKENING CLOUD COVER WITH VERY LITTLE IN THE WAY OF LIFT OBSERVED IN THE NUMERICS. THIS DOES CHANGE SOMEWHAT SUNDAY NIGHT AS 850-700MB THETA-E ADVECTION INCREASES FROM EAST TO WEST WITH ELEVATED INDICES AND LAPSE RATES LESS THAN IMPRESSIVE FOR THUNDER. HOWEVER...WE WILL INTRODUCE A SLIGHT CHANCE FOR RAIN SHOWERS AS AFOREMENTIONED MOISTURE AND ADVECTION INCREASES ACROSS THE REGION. WE WILL MONITOR MONDAY TRENDS AS SURFACE LOW TRACKS EAST OF THE REGION WITH DEFORMATION AXIS AND POTENTIAL TROWAL DEVELOPS ACROSS THE REGION. OUR CHANCE FOR SHOWERS/THUNDERSTORMS LOOKS GOOD IN THE CURRENT FORECAST AND NO PLANS TO CHANGE AT THIS TIME. BUT GIVEN OUR RECENT HEAVY RAINFALL THIS WILL NEED TO BE MONITORED. THEN FOR THE REMAINDER OF THE WEEK AS OUR NORTHWEST FLOW MATURES AROUND DEEP HUDSON BAY LOW... ADDITIONAL SHORT WAVE SUPPORT DIVES INTO THE WESTERN LAKES REGION DURING THE MID WEEK PERIOD. THE ECMWF IS QUITE ROBUST WITH THIS WAVE AS THE GFS SEEMS TO SUFFER FROM CONVECTIVE GRID SCALE FEEDBACK WHICH MAKES ITS SURFACE AND QPF FIELDS UNRELIABLE. NEVERTHELESS...IT DOES CONFIRM ACTIVE PATTERN FOR NEXT WEEK WITH TEMPERATURES AVERAGING AT OR SLIGHTLY BELOW NORMAL. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...SMALL CRAFT ADVISORY...LHZ421...NEARSHORE WATERS FROM PORT AUSTIN TO PORT HURON UNTIL 4 PM FRIDAY. LAKE ST CLAIR...NONE. MI WATERS OF LAKE ERIE...NONE. && $$ UPDATE.......BRAVENDER AVIATION.....CONSIDINE SHORT TERM...CONSIDINE LONG TERM....BGM YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE). mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LOUISVILLE KY 310 PM EDT FRI JUN 22 2006 SHORT TERM (TONIGHT AND SATURDAY)... SURFACE ANALYSIS SHOWS A WEAK SURFACE TROUGH LYING ACROSS KENTUCKY. A COLD FRONT IS INDICATED BY A WIND SHIFT ALONG THE OHIO RIVER ATTM. NORTH OF THIS FRONT...DEWPOINTS ARE STILL HIGH...DRIER AIR IS STILL NORTH OF INDIANAPOLIS. EXTENSIVE CLOUD COVER HAS LIMITED INSTABILITY...AND THUNDERSTORM DEVELOPMENT ACROSS ALL BUT OUR SOUTHEASTERNMOST COUNTIES UNTIL NOW. HOWEVER...EXPECT AFTERNOON CONVECTIVE COVERAGE TO EXPAND OVER TWO LOCALES. THE FIRST WILL BE ACROSS OUR SOUTHEASTERN COUNTIES...WHERE INSTABILITY IS GREATEST. THE SECOND AREA OF (FOR NOW) LIGHT SHOWERS IS CURRENTLY DEVELOPING ACROSS SOUTHERN INDIANA. THIS IS ASSOCIATED WITH SURFACE TROUGH. FEEL THAT MOST WIDESPREAD STORM COVERAGE LATE THIS AFTERNOON WILL STILL LIE ACROSS OUR SOUTHEASTERN STATES WHERE PRECIPITATION AMOUNTS WILL BE THE GREATEST AS WELL. BOTH THE MESOETA AND RUC SHOWED THESE TWO SEPARATE AREAS OF DEVELOPMENT FOR THIS AFTERNOON. FEEL THAT SEVERE POTENTIAL IS QUITE LIMITED DUE TO WEAK INSTABILITY. A FEW STORMS ACROSS THE SOUTHEAST MAY BECOME STRONG WITH ISOLATED DAMAGING WIND GUSTS...BUT FEEL THE THREAT IS NOT WIDESPREAD. STORMS THAT DO FORM WILL MOVE NORTHEAST QUICKLY ENOUGH THAT RUNOFF PROBLEMS ARE NOT ANTICIPATED. OVERNIGHT...AS HIGH PRESSURE BUILDS ACROSS THE GREAT LAKES...WINDS WILL SHIFT TO THE NORTH...ALLOWING DRIER AIR TO FILTER SOUTHWARD ACROSS THE STATE...THUS ENDING PRECIPITATION CHANCES. FEEL THAT CLEARING WILL BE SLOW TONIGHT AS RESIDUAL LOW LEVEL MOISTURE WILL PERSIST. TOMORROW SHOULD FEEL DISTINCTLY LESS HUMID AS DEWPOINTS FALL TO AROUND 60 AND WINDS BECOME NORTHEASTERLY. EXPECT QUITE A BIT OF SUN AND NEAR SEASONAL TEMPERATURES. JSD .LONG TERM (SATURDAY NIGHT THROUGH FRIDAY)... PERIOD WILL FEATURE RIDGE OVER THE WEST AND TROUGH IN THE EAST. AFTER UNEVENTFUL SUNDAY...STRONG SHORT WAVE DROPPING SOUTHEAST INTO THE OHIO VALLEY WILL BRING CHANCE SHOWERS/THUNDERSTORMS SUNDAY NIGHT THROUGH TUESDAY. IF TROUGH CUTS OFF...AS HINTED AT ON THE NAM...PRECIP THREAT COULD LINGER BEYOND TUESDAY. CURRENTLY NAM WEAKENS TROUGH AND GFS SEES NEXT SHORT WAVE ROTATING AROUND HUDSON BAY VORTEX NUDGING IT OUT TO THE NORTHEAST. REST OF WEAK WILL BE QUIET WITH NO SIGNIFICANT SHORT WAVES AND TEMPERATURES GENERALLY AT OR BELOW AVERAGE. HIGHS IN THE MID 80S MAY TURN OUT TO BE A BIT TOO WARM MONDAY AND TUESDAY...DEPENDING ON THE PERSISTENCE OF CLOUDS WITH THE APPROACHING SHORT WAVE. -REITMEYER && .LMK WATCHES/WARNINGS/ADVISORIES... KY...NONE. IN...NONE. && $$ JSD ky AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC 545 PM EDT FRI JUN 23 2006 .MESOSCALE UPDATE... WATER VAPOR LOOP INDICATES A WEAK POSITIVELY TILTED TROUGH FROM AN UPPER LOW ACROSS THE HUDSON BAY REGION SOUTHWEST INTO THE PLAINS. WEAK WAVES ARE TRANSLATING NORTHEAST WITHIN THE MEAN FLOW FROM THE TENNESSEE VALLEY INTO THE MID ATLANTIC. ACARS 400-250MB WIND OBSERVATIONS INDICATED A 80-100KT JET FROM THE WESTERN GREAT LAKES NORTHEAST ALONG THE CANADIAN BORDER. 21Z MESOANALYSIS PLACED A SERIES OF 2 TROUGHS IN THE LEE OF THE APPALACHIANS...WITH A MESOHIGH NEAR NORFOLK. THE SYNOPTIC COLD FRONT REMAINS WELL REMOVED FROM THE REGION...NEAR THE EASTERN GREAT LAKES. SEVERAL WEAK SHOWERS ARE DEVELOPING IN THE PROXIMITY OF THE LEE TROUGH...WHERE CLEARING OCCURRED DURING THE MID AFTERNOON. RICH SURFACE DEWPOINTS (70F+) ARE CURRENTLY CONFINED TO THE SOUTHEAST PORTION OF THE FORECAST AREA. WITH SUNSET...EXPECT PARCEL ACCELERATION ATOP THE BOUNDARY LAYER GIVEN THE APPROACH OF THE SYNOPTIC COLD FRONT. THIS UPGLIDE...AS SEEN ON THE NAM/RUC 310K ISENTROPIC ANALYSIS FROM 00Z-06Z ALONG THE INTERSTATE 95 CORRIDOR...MAY ACT AS THE LIFT NEEDED TO INITIATE DEEP CONVECTION. PROXIMITY TO THE RICH BOUNDARY LAYER MOISTURE AND OLD CONVECTIVE OUTFLOWS SUGGEST THE INTERSTATE 95 CORRIDOR EAST SHOULD BE THE PRIMARY AREA FOR CONVECTIVE DEVELOPMENT AFTER SUNSET. RUC/NAM BUFKIT FORECAST SOUNDINGS INDICATE THIS UPGLIDE WILL ALLOW CONTINUED SATURATION OF BOUNDARY LAYER NEAR THE INTERSTATE 95 CORRIDOR...WITH CAPES INCREASING FROM LESS THAN 1000 J/KG THIS AFTERNOON TO OVER 2000 J/KG LATE THIS EVENING. FORECAST SHEAR VALUES REMAIN WEAK DURING THE PERIOD...HOWEVER A SLIGHT INCREASE TREND IS NOTED THIS EVENING. WITH PRECIPITABLE WATER VALUES RISING FROM AN OBSERVED VALUE OF 1.8" (GPS SENSOR NEAR DC AT 20Z) TO 2.2" BY 3Z ON NAM BUFKIT SOUNDINGS...AND MODEL SOUNDINGS INDICATING DEEP WARM CONVECTIVE CLOUDS (-5C AT 17.0 KFT)...TRAINING OR SLOW MOVING STORMS MAY CARRY AN ENHANCED RISK OF LOCALIZED FLASH FLOODING ACROSS THE BALTIMORE-WASHINGTON METRO AREAS. && .SHORT TERM (TONIGHT-SAT) FRONTAL BDRY STRETCHING FROM NEW ENGLAND SWWD TO SWRN PA WILL SLOWLY SAG SWED TONIGHT AND STALL FROM SERN PA TO ERN WV HIGHLANDS. WAVES OF LOW PRES TO RIDE ALG FRONT COMBINED WITH AN INCREASE IN PRECIP WATER VALUES WILL LEAD TO PERIODS OF HVY RAIN NEXT 36 HRS. OBVIOUSLY...PRECIP CHANCES ARE VERY HIGH BUT LOOKS LIKE AXIS OF HEAVIEST RAINFALL LOOKS TO BE FROM NE MD SWWD TO NRN VA. BELIEVE SVR THREAT IS VERY LIMITED DUE TO NEARLY MOIST ADIABATIC PROFILES AND VERY LOW SHEAR. && AVIATION...VFR CONDITIONS THRU 00Z. THEN PREDOMINANT MVFR WITH POSSIBLE IFR IN HEAVY RAIN. && .MARINE... NO MARINE CONCERNS AT THIS TIME. SEEMS AS THOUGH FRONTAL BNDRY TOO FAR NORTH TO CAUSE A SIG CONCERN FOR TIDAL FLOODING AT THIS TIME. && .LONG TERM... SATURDAY NIGHT THROUGH FRIDAY... FRONTAL ZONE PRECIPITATION...MOIST ADVECTION PTTN CONTINUES TIL MONDAY OR MON NGT AT LEAST. SAT NGT THROUGH SUN NGT LOOKS LIKE A PERIOD OF PTNL HVY RAINFALL DUE TO MADDOX TYPE FRONTAL RAINFALL PATTERN WITH LLJ WORKING ALONG THE WARM SIDE OF THE FRONTAL ZONE. FRONTAL ZONE AND ENERGY IS SHUNTED TO THE NW ON MON ACCORDING TO THE LATEST GFS MED RG BUT THEN MOVES BACK OVR THE MID ATLC ON TUE. WILL INDICATE LIKELY POPS THROUGH SUN WHICH IS IN LINE WITH THE LATEST MOS POPS...THEN TAPER POPS BACK INTO THE CHC CAT INTO THE MIDDLE OF NEXT WEEK. HPC 5-DAY QPF MAX CONTOUR OVR THE NRN SHENANDOAH VLY OF UP TO 9 INCHES. PATTERN FROM NAM IS SIMILAR TO GFS THOUGH QPF IS A LITTLE LESS. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...FLASH FLOOD WATCH FOR DCZ001 FROM 8 PM FRIDAY TO 8 AM SUNDAY. MD...FLASH FLOOD WATCH FOR MDZ002>007-009>011-013-014 FROM 8 PM FRIDAY TO 8 AM SUNDAY. VA...FLASH FLOOD WATCH FOR VAZ021-025>031-038>042-051>054 FROM 8 PM FRIDAY TO 8 AM SUNDAY. WV...FLASH FLOOD WATCH FOR WVZ048>055 FROM 8 PM FRIDAY TO 8 AM SUNDAY. MARINE...NONE. && $$ MESOSCALE UPDATE...ROGOWSKI SHORT TERM/LONG TERM...LFR/JB md AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 145 PM EDT FRI JUN 23 2006 .AVIATION... THICK CIRRUS REMAINS ENTRENCHED ACROSS DTW/DET...WHILE MORNING STRATUS CONTINUES TO MIX OUT AT FNT/MBS. 16Z/17Z TAMDAR SOUNDINGS CONTINUE TO SHOW DRIER AIR FILTERING IN FROM THE NORTH...WITH CU DIMINISHING WITH SUNSET AND CIRRUS ONLY LASTING THROUGH THE EVENING BEFORE SKIES CLEAR OUT. SURFACE HIGH OVER NORTHERN LOWER WILL DROP DOWN THROUGH CENTRAL LOWER OVERNIGHT...LEADING TO NEARLY CALM CONDITIONS AT FNT/MBS WITH DECOUPLING UNDER CLEAR SKIES. NOT MUCH CHANGE TO THE VFR CONDITIONS/LIGHT WINDS BY THE END OF THE TAF PERIOD SATURDAY MORNING...WITH JUST SOME CIRRUS MAKING IT INTO THE NORTHERN CWA FROM CONVECTION WELL UPSTREAM. && .UPDATE...1121 AM EDT FRI JUN 23 2006 EARLY MORNING STATUS HAS BEEN HANGING TOUGH ACROSS WEST-CENTRAL CWA...WITH THE NORTHERN EDGE STARTING TO MIX OUT. WILL UPDATE TO CARRY CLOUDS LONGER ACROSS THE NORTH...BUT STILL EXPECT THE CU/SC TO MIX OUT AS MUCH DRIER AIR ADVECTS IN ABOVE THE INVERSION. 12Z DTX/13Z TAMDAR SOUNDINGS SHOW A FAIR AMOUNT OF LOW-LEVEL MOISTURE ACROSS THE SOUTH...WITH 12Z RUC/NAM STILL TRYING TO GENERATE A COUPLE HUNDREDTHS QPF THIS AFTERNOON. 12Z RUC FORECAST SOUNDINGS SHOW THE LOW-LEVEL LEVELS SATURATING WITH STEEP LOW-LEVEL LAPSE RATES...BUT WITH CU FIELD CURRENT SUPPRESSED BY HIGHER CLOUDS AND A STRONGER INVERSION WILL STICK WITH THE DRY FORECAST. TWEAKED TEMPERATURES A BIT GIVEN THE MORE PERSISTENT CLOUD COVER ACROSS NORTHWESTERN CWA...IN ADDITION NORTH/NORTHEASTERLY FLOW OFF LAKE HURON. && .PREV DISCUSSION...ISSUED 337 AM EDT FRI JUN 23 2006 SHORT TERM...TODAY AND TONIGHT THE 07Z SURFACE ANALYSIS SHOWS HIGH PRESSURE CENTERED OVER THE WESTERN UP WITH THE PRIMARY SURFACE COLD FRONT EXTENDING FROM THE MID MISSISSIPPI VALLEY TO WESTERN NEW YORK STATE. A SECONDARY COLD FRONT...MARKING THE LEADING EDGE OF MUCH DRYER LOW LEVEL AIR...IS LOCATED OVER THE DETROIT AREA. THE CURRENT WATER VAPOR LOOP AND 00Z UPPER AIR PLOTS SHOW AN UPPER LOW OVER FAR NORTHERN QUEBEC WITH MORE ZONAL FLOW ACROSS THE NORTHERN CONUS. ALSO SHOWN ON THE WATER VAPOR LOOP IS A POCKET OF DRY MID LEVEL AIR LOCATED OVER THE NORTHERN AND WESTERN GREAT LAKES REGION...IN THE VICINITY OF THE SURFACE HIGH PRESSURE. THE UPPER LOW OVER NORTHERN QUEBEC IS EXPECTED TO DEEPEN SLIGHTLY TODAY AND RESULT IN SOME MINOR MID LEVEL HEIGHT FALLS ACROSS THE STATE...ALLOWING THE MID LEVEL WIND FIELD TO VEER MORE WEST-NORTHWESTERLY. THIS WILL ALLOW THE SURFACE HIGH PRESSURE TO BUILD INTO THE LOWER PENINSULA TODAY. NORTH-NORTHEASTERLY LOW LEVEL FLOW AROUND THIS HIGH WILL HELP ADVECT MUCH DRYER AIR INTO SE MICHIGAN. SURFACE DEWPOINTS UPSTREAM ARE ACTUALLY IN THE 40S. AS OF 07Z...THERE IS A SOLID OVERCAST OF MID AND HIGH CLOUDS ACROSS SE MICHIGAN. ENTRANCE REGION OF A SEASONALLY STRONG UPPER LEVEL JET ACROSS EASTERN CANADA APPEARS TO HAVE LED TO THE INCREASE IN HIGH CLOUDS. THIS FORCING AND HIGH LEVEL MOISTURE WILL SLOWLY PUSH SOUTHEAST DURING THE COURSE OF THE DAY. SHALLOW LOW LEVEL COLD AIR ADVECTION WILL ALLOW SOME SCATTERED TO OVERCAST STRATUS/STRATO CU TO DEVELOP THIS MORNING. THIS WILL BE MORE LIKELY ACROSS THE SAGINAW VALLEY AND THUMB WHERE NORTHEASTERLY FLOW OFF LAKE HURON WILL ADD SOME MOISTURE TO THE BOUNDARY LAYER AND WHERE THE LOW LEVEL INVERSION WILL BE STRONGER. INTERESTING TO NOTE THAT THE GFS AND WRFHEMI SOLUTIONS SHOW A COUPLE HUNDREDTHS OF QPF ACROSS LENAWEE AND MONROE COUNTIES TODAY ALONG THE 700MB FRONTAL BOUNDARY. SINCE CONVECTION ACROSS THE OHIO VALLEY HAS PUSHED WELL SOUTH OF WHERE THE GFS SOLUTION WOULD INDICATE AND GIVEN THE AMOUNT OF STABILITY OVER THE STATE...PREFER THE NAM SOLUTION WHICH KEEPS MEASURABLE PRECIP JUST SOUTH OF THE STATE TODAY. THE POTENTIAL FOR LIGHT SHOWERS SOUTH OF THE I-94 CORRIDOR WILL STILL HAVE TO BE MONITORED THROUGHOUT THE DAY THOUGH. THE NAM SOLUTION BECOMES QUITE ROBUST WITH THE AMOUNT OF LOW LEVEL MOISTURE THIS MORNING. THUS...ITS SOLUTION INDICATES THAT IT WILL TAKE WELL INTO THE AFTERNOON FOR THE LOWER CLOUDS TO MIX OUT. SINCE THE NAM INITIALIZED SIGNIFICANTLY TOO MOIST BELOW 800MB BASED ON THE 00Z KAPX AND KGRB SOUNDINGS...THINK ANY LOW CLOUDS THAT ARE ABLE TO DEVELOP THIS MORNING WILL MIX OUT RATHER QUICKLY BY EARLY AFTERNOON...EXCEPT FOR PERHAPS ALONG THE IMMEDIATE LAKE HURON SHORELINE. THERE SHOULD BE ENOUGH INSOLATION THROUGH THE HIGHER CLOUDS TO SIDE WITH THE HIGHER MAV MOS GUIDANCE VALUES OF MID 70S INLAND TO UPPER60S/LOWER 70S NEAR LAKE HURON. OPTIMAL RADIATIONAL COOLING CONDITIONS ARE EXPECTED TONIGHT WITH THE SURFACE HIGH OVERHEAD ALONG WITH THE CLEAR SKIES AND MUCH LOWER SURFACE DEWPOINTS. SEE NO REASON TO DEVIATE MUCH FROM GUIDANCE WHICH DROPS MINS INTO THE MID TO UPPER 40S ACROSS THE NORTH HALF OF THE FORECAST AREA. LONG TERM...SATURDAY THROUGH FRIDAY IT SEEMS WE WILL TRANSITION TOWARD WEST COAST RIDGE AND GREAT LAKES TROUGH THROUGH THE UPCOMING LONG TERM OF THIS FORECAST WHICH WILL PROVIDE OUR CHANCES FOR MORE RAIN. A FAIRLY ZONAL FLOW ACROSS NOAM WITH A NOTABLE SHEAR AXIS FROM ALBERTA INTO SASKATCHEWAN AS HUDSON BAY LOW ROTATES IN A QUASI-STATIONARY POSITION. AS ADDITIONAL SHORT WAVE ENERGY UNDERCUTS THIS SHEAR AXIS...THE WEST COAST RIDGE WILL BEGIN TO AMPLIFY AND IN TURN ALLOW THIS WAVE TO DIVE SOUTHEAST AND EVENTUALLY DEVELOP A CUT OFF UPPER LOW WHICH GFS/ECMWF SUGGEST WILL OCCUR IN THE VICINITY OF NORTHERN ILLINOIS MONDAY-TUESDAY TIME FRAME. THEN WE FIND OURSELVES WITHIN A NORTHWEST FLOW REGIME WHICH COULD PROVE TO BE INTERESTING AS BAROCLINICITY WILL BE INCREASING SOMEWHERE ACROSS THE NORTHERN 1/3RD OF THE COUNTRY WITH NOCTURNAL LOW LEVEL JET LIKELY DEVELOPING CONVECTION NEAR AND NORTH OF THIS BOUNDARY. SATURDAY LOOKS TO BE A GOOD START TO THIS WEEKEND AS UPSTREAM SHORT WAVE APPROACHES THE NORTHERN PLAINS INTO THE UPPER MISSISSIPPI RIVER VALLEY. AT THE SURFACE...HIGH PRESSURE REMAINS IN CONTROL BUT AS CONVECTION DEVELOPS IN RESPONSE TO THIS APPROACHING SHORT WAVE...CLOUD DEBRIS WILL BE INCREASING ACROSS THE CWA. DESPITE THAT OUR TEMPERATURES WILL GENERALLY FALL INTO THE UPPER 70S BASED ON 850MB TEMPS AOA 12C. THE EXCEPTION TO THIS WILL BE NEAR LAKE HURON AS LAKE BREEZE DEVELOPMENT AND/OR LIGHT ONSHORE FLOW AROUND THE PERIPHERY OF THIS SURFACE HIGH WILL KEEP TEMPS A BIT COOLER...LOWER 70S. AT THIS TIME WE WILL KEEP SATURDAY NIGHT DRY ALTHOUGH WE DO EXPECT PLENTY OF CLOUD COVER INCREASING FROM WEST TO EAST. NUMERICAL SUITE OFFERS A VARIETY OF IDEAS WITH GFS SUGGESTING CONVECTIVE COMPLEX APPROACHING THE WESTERN PORTIONS OF OUR CWA OVERNIGHT WITH THE NMM MORE COMPACT AND FURTHER WEST. ECMWF IS EVEN SLOWER HENCE OUR DRY FORECAST WITH TEMPERATURES DROPPING INTO THE MIDDLE 50S. ON SUNDAY THE UPPER LOW WILL BE DEVELOPING UPSTREAM FROM US WHILE DOWNSTREAM MOISTURE TRANSPORT INCREASING. THIS PLACES OUR REGION SANDWICHED WITH THICKENING CLOUD COVER WITH VERY LITTLE IN THE WAY OF LIFT OBSERVED IN THE NUMERICS. THIS DOES CHANGE SOMEWHAT SUNDAY NIGHT AS 850-700MB THETA-E ADVECTION INCREASES FROM EAST TO WEST WITH ELEVATED INDICES AND LAPSE RATES LESS THAN IMPRESSIVE FOR THUNDER. HOWEVER...WE WILL INTRODUCE A SLIGHT CHANCE FOR RAIN SHOWERS AS AFOREMENTIONED MOISTURE AND ADVECTION INCREASES ACROSS THE REGION. WE WILL MONITOR MONDAY TRENDS AS SURFACE LOW TRACKS EAST OF THE REGION WITH DEFORMATION AXIS AND POTENTIAL TROWAL DEVELOPS ACROSS THE REGION. OUR CHANCE FOR SHOWERS/THUNDERSTORMS LOOKS GOOD IN THE CURRENT FORECAST AND NO PLANS TO CHANGE AT THIS TIME. BUT GIVEN OUR RECENT HEAVY RAINFALL THIS WILL NEED TO BE MONITORED. THEN FOR THE REMAINDER OF THE WEEK AS OUR NORTHWEST FLOW MATURES AROUND DEEP HUDSON BAY LOW... ADDITIONAL SHORT WAVE SUPPORT DIVES INTO THE WESTERN LAKES REGION DURING THE MID WEEK PERIOD. THE ECMWF IS QUITE ROBUST WITH THIS WAVE AS THE GFS SEEMS TO SUFFER FROM CONVECTIVE GRID SCALE FEEDBACK WHICH MAKES ITS SURFACE AND QPF FIELDS UNRELIABLE. NEVERTHELESS...IT DOES CONFIRM ACTIVE PATTERN FOR NEXT WEEK WITH TEMPERATURES AVERAGING AT OR SLIGHTLY BELOW NORMAL. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...SMALL CRAFT ADVISORY...LHZ421...NEARSHORE WATERS FROM PORT AUSTIN TO PORT HURON UNTIL 4 PM FRIDAY. LAKE ST CLAIR...NONE. MI WATERS OF LAKE ERIE...NONE. && $$ AVIATION.....BRAVENDER UPDATE.......BRAVENDER SHORT TERM...CONSIDINE LONG TERM....BGM YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE). mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX 1226 PM CDT FRI JUN 23 2006 .AVIATION... ALTHO MOISTURE LEVELS ARE SLIGHTLY LOWER THAN YESTERDAY...STILL FEEL AN ACTIVE SEA BREEZE WILL DEVELOP THIS AFTERNOON. HAVE LEANED HEAVILY TOWARD THE RUC WHICH DEVELOPS A SEA BREEZE BUT DOES NOT LET THE FEATURE PENETRATE INLAND. HAVE FOCUSED PRECIP OVER THE FIRST TWO TIERS OF COUNTIES. WINDS ARE ALL OVER THE PLACE BUT EXPECT SE WINDS BEHIND THE SEA BREEZE AND LIGHT WEST AHEAD OF IT. .DISCUSSION...SATELLITE AND RADAR IMAGES INDICATE SHOWERS AND THUNDERSTORMS WEAKENING ACROSS PORTIONS OF NORTH AND NORTHWEST TEXAS THIS MORNING. THE QUESTION IS REDEVELOPMENT ALONG THE OUTFLOW BOUNDARY THIS AFTERNOON. LAPS SURFACE ANALYSIS INDICATED HIGHER INSTABILITY NORTHWEST OF THE CWA AND WITH DIURNAL HEATING INSTABILITY EXPECTED TO INCREASE THIS AFTERNOON ACROSS SOUTHEAST TX. ALSO...PRECIPITABLE WATER VALUES PROGGED TO INCREASE ACROSS NORTHERN PORTIONS OF THE CWA THIS AFTERNOON INTO TONIGHT AS MOISTURE POOLS ALONG THE CONVECTIVE BOUNDARY TO THE NORTHWEST. WILL GO AHEAD AND INCREASE POPS SLIGHTLY NORTHWEST TODAY WHERE GREATER INSTABILITY AND HIGHER PW'S WILL RESIDE. ALSO...WITH PRECIPITABLE WATER VALUES NEAR 1.5 TO 1.75 INCHES BELIEVE HEAVY RAINFALL POSSIBLE WITH STORMS THIS AFTERNOON AND WITH THE SLOW STORM MOTIONS INDICATED BY AREA SOUNDINGS BELIEVE VERY LOCALIZED HEAVY RAINFALL AMOUNTS LIKELY. WILL UPDATE ZONES/GRIDS TO MENTION HEAVY RAINFALL WITH THUNDERSTORMS. REST OF THE FORECAST LOOKS FINE AS ISOLATED SHOWERS AND THUNDERSTORMS LIKELY TO DEVELOP TODAY WITH AFTERNOON SEABREEZE. 32 && .PREV DISCUSSION... (ISSUED 610 AM CDT FRI JUN 23 2006) AVIATION... PATCHY MVFR FOG AND STRATUS IS EXPECTED TO PERSIST UNTIL 14Z THEN QUICKLY BURN OFF. SOME BRIEF MVFR CEILINGS ARE POSSIBLE BEYOND THAT UNTIL AROUND 17Z AS CUMULUS BUILDS WITH DAYTIME HEATING. ISOLATED CONVECTION IS EXPECTED TO DEVELOP GENERALLY FROM HOUSTON AREA NORTHWARD IN THE 18Z-20Z TIME FRAME AND PERSIST UNTIL SUNSET. HOWEVER...COVERAGE IS EXPECTED TO BE CONSIDERABLY LESS THAN YESTERDAY SO ONLY CODED CBS IN THE TAFS. PATCHY MVFR FOG/STRATUS IS EXPECTED TO FORM AGAIN AFTER 08Z MAINLY AFFECTING RURAL SITES. 35 DISCUSSION...RADAR MUCH MORE QUIET TONIGHT COMPARED TO THE PAST COUPLE NIGHTS AT THIS TIME. HOWEVER...A BIT HESITANT TO KEEP POPS COMPLETELY OUT OF THE FCST TODAY FOR A FEW REASONS. PW'S SHOULD REMAIN IN THE 1.5-1.7" RANGE FOR MOST OF THE DAY. GRADIENT SHOULD FLATTEN WHICH WOULD ALSO FAVOR AN ACTIVE AFTN SEABREEZE. THIS ALONG WITH DAYTIME HEATING COULD BECOME A FOCUS FOR ISOLATED TSTMS. DAYSHIFT WILL ALSO NEED TO WATCH THE STORMS IN OK...AR...AND N TX AS A FEW MODELS SHOW THEM SENDING SOME OUTFLOWS INTO OUR NRN ZONES BY LATE AFTERNOON/EVENING. THOUGH DON'T EXPECT MUCH PRECIP COVERAGE...WHAT DOES FALL COULD BE LOCALLY HEAVY AS STORM MOTIONS SHOULD GENERALLY BE <7 KT. GFS...CANADIAN & ECMWF ALL SHOW A SLOW MOVING FRONTAL BOUNDARY MAKING IT TO OR MAYBE EVEN OFF THE COAST BY LATE SUNDAY NIGHT. UPPER FLOW DOES SUPPORT SUCH A SCENARIO...SO WILL BE MAKING SOME TWEAKS TO THE FCST THROUGH THE MIDDLE OF NEXT WEEK. WILL BE ADDING SOME POPS BACK INTO THE FCST AS RESPECTABLE PW'S POOL AHEAD OF AND ALONG THE BOUNDARY. FCST STORM MOTIONS STILL VERY SLOW SO WILL NEED TO WATCH FOR THE POCKETS OF LOCALLY HEAVY RAIN IF MESOSCALE FEATURES DON'T TAKE OVER. WILL ALSO LOWER TEMPS...ESP OVERNIGHT LOWS...BEGINNING MONDAY NIGHT. HOW DO LOWS IN THE 60S IN LATE JUNE SOUND? HOW ABOUT AFTERNOON RH'S IN THE 30S? BACK TO REALITY BY THE 2ND HALF OF NEXT WEEK WHEN THE GULF IS ALLOWED TO OPEN BACK UP AND CONDITIONS MODERATE BACK TOWARD NORMAL. 47 MARINE... SURFACE HIGH OFF THE LOUISIANA COAST WILL KEEP LIGHT ONSHORE FLOW IN PLACE OVER THE WATERS TODAY. BEGINNING TONIGHT THIS HIGH WILL MOVE ALMOST DIRECTLY OVERHEAD. EXPECT THE LANDBREEZE/SEABREEZE INTERACTION TO DOMINATE THIS WEEKEND WITH ONSHORE WINDS IN THE AFTERNOONS/EARLY EVENINGS BECOMING OFFSHORE IN THE LATE NIGHTS AND MORNINGS. SPEEDS WILL BE LESS THAN 10 KNOTS AND SEAS GENERALLY 2 FEET OR LESS. MODELS INDICATE A WEAK COLD FRONT CROSSING THE WATERS SUNDAY NIGHT OR MONDAY. WHILE THIS IS RARE IN LATE JUNE...THE UPPER PATTERN SUPPORTS IT...SO WILL FORECAST NORTH/NORTHEAST WINDS MONDAY/TUESDAY WITH SPEEDS REMAINING LIGHT. 35 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ tx