Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 06/18/14


AREA FORECAST DISCUSSION...UPDATED
NWS RENO NV
433 PM PDT TUE JUN 17 2014 .UPDATE... QUICK UPDATE THIS AFTERNOON TO EXTEND THE SHOWERS AND THUNDERSTORM CHANCES SOUTH OF RENO INTO CARSON CITY AND LAKE TAHOE AS THE SHORTWAVE PUSHES INTO NORTHERN NEVADA. THERE IS CONVECTIVE DEVELOPMENT OVER THE CARSON RANGE WEST OF RENO-CARSON AND COULD POTENTIALLY PRODUCE LIGHT RAIN, GUSTY WINDS AND POSSIBLY OCCASIONAL LIGHTNING. SHOWERS NORTH OF INTERSTATE 80 CONTINUE TO PUSH SOUTHWARD INTO THE PYRAMID LAKE AND LOVELOCK AREAS THIS AFTERNOON, BUT HAVE SO FAR REMAINED JUST SHOWERS WITH NO LIGHTNING STRIKES DETECTED. GUSTY OUTFLOW WINDS FROM THESE SHOWERS ARE ALSO POSSIBLE AND COULD CREATE SOME LOCALIZED BLOWING DUST NEAR DRY LAKE BEDS. && .PREVIOUS DISCUSSION... /ISSUED 224 PM PDT TUE JUN 17 2014/ SYNOPSIS... A COLD LOW PRESSURE SYSTEM WILL EXIT THE REGION AND RESULT IN DRIER CONDITIONS AND MUCH WARMER TEMPERATURES BEGINNING WEDNESDAY AFTERNOON AND PERSISTING THROUGH THE WEEKEND. A FEW COLDER SIERRA VALLEYS WILL DROP NEAR OR SLIGHTLY BELOW FREEZING TONIGHT WITH A FEW 30S IN OUTLYING COLDER VALLEYS IN WESTERN NEVADA. SHORT TERM... SHORTWAVE THAT BROUGHT SHOWERS AND MEASURABLE RAINFALL TO PARTS OF NORTHEAST CA AND NORTHWEST NV HAS EXITED WITH SUBSIDENCE AND DRIER AIR ALOFT HELPING TO ERODE CUMULUS FIELD ALONG THE EASTERN SIERRA AND WESTERN NV. SATELLITE IMAGERY SHOWS ANOTHER SHORTWAVE DROPPING SOUTHEASTWARD TOWARD THE AREA WHICH WILL TRACK MAINLY ACROSS NORTHWEST INTO CENTRAL NV ON BACK SIDE OF UPPER LOW WHERE INSTABILITY WILL BE MORE FAVORABLE THROUGH EARLY THIS EVENING FOR A FEW SHOWERS. THE NAM CONTINUES TO HOLD A NARROW BAND OF SHOWERS TOGETHER ON THE FAR WESTERN EDGE AS IT APPROACHES RENO 00Z-03Z. OTHER MODELS INCLUDING THE HRRR DO NOT SHOW THIS EXTENSION. CONFIDENCE IS LOW BUT WILL INCLUDE IT FOR AREAS JUST NORTH OF RENO INCLUDING PYRAMID LAKE. BEST FORCING/CONVERGENCE IS ACROSS NORTH CENTRAL-NORTHEAST NV WITH A THUNDERSTORM OR TWO POSSIBLE ACROSS THE BASIN AND RANGE. TEMPERATURES WILL BE QUITE COLD TONIGHT AS SKIES CLEAR AND WINDS DECREASE. THE AIRMASS IS NOT PARTICULARLY DRY AND THUS TEMPERATURES MAY NOT GET AS LOW AS SOME OF THE COLDEST MOS GUIDANCE. HOWEVER, COLDER SIERRA VALLEYS WILL LIKELY SEE A LIGHT FREEZE WITH EVEN SOME OF THE OUTLYING COLDER WESTERN NV VALLEYS DROPPING INTO THE 30S BY WEDNESDAY MORNING. IF YOUR LOW IS FORECAST TO DROP BELOW 40 DEGREES, YOU MAY WANT TO CONSIDER TAKING SOME GENERAL PRECAUTIONS TO PROTECT SENSITIVE PLANTS. HEIGHTS BEGIN TO RISE WEDNESDAY AFTERNOON INTO THURSDAY FOR A FAST WARMUP. TEMPERATURES IN COLDER SIERRA VALLEYS WILL NOT BE AS COLD THURSDAY MORNING ALTHOUGH THEY COULD STILL GET DOWN TO NEAR OR JUST ABOVE FREEZING FOR ONE MORE NIGHT. DAYTIME HIGHS WILL REMAIN JUST SHY OF NORMAL FOR WEDNESDAY BUT REBOUND TO ABOVE NORMAL FOR THURSDAY WITH 70S SIERRA VALLEYS AND 80S WESTERN NV. HOHMANN LONG TERM...FRIDAY THROUGH TUESDAY... THE LONG TERM FORECAST REMAINS UNCHANGED. THE REGION WILL REMAIN ANCHORED BETWEEN A NORTHEAST PACIFIC TROUGH AND ROCKIES/NORTHERN PLAINS RIDGE THROUGH THE LONG TERM FORECAST, WITH A FEW MINOR DISTURBANCES PERIODICALLY MOVING OVERHEAD. THE GFS REMAINS THE STRONGEST WITH THE FRIDAY DISTURBANCE ALTHOUGH EVEN IT IS SHIFTING NORTH WITH THE BEST LOW-MID LEVEL INSTABILITY AND FORCING OVER EXTREME NORTHEAST CALIFORNIA, NORTHWESTERN NEVADA AND OREGON. MEANWHILE, THE ECMWF/GEM LOOK VERY WEAK AND FLAT WITH FRIDAY`S DISTURBANCE WITH LITTLE INDICATION OF THUNDERSTORMS. THE OTHER THING OF SOME CONCERN FRIDAY WILL BE WINDS FOR NORTHEAST CALIFORNIA AND GENERALLY NORTH OF HIGHWAY 50 INTO FAR WESTERN NEVADA (SIERRA FRONT). GRADIENTS INCREASE WITH THE MOS HIGH TEMPERATURE BETWEEN THE SIERRA (TRUCKEE) AND WEST-CENTRAL NEVADA (LOVELOCK) IMPLYING INCREASED WINDS WITH GUSTS TO AROUND 30 MPH POSSIBLE FOR THE SIERRA FRONT. SATURDAY THROUGH TUESDAY, EASTERN CALIFORNIA AND WESTERN NEVADA WILL REMAIN IN FLAT SOUTHWEST-WEST FLOW ALOFT. THIS WILL BRING THE TYPICAL DAILY ZEPHYR BREEZES FOR THE EASTERN SIERRA AND OUT INTO WESTERN NEVADA. DEPENDING ON THE SMALL-SCALE, LOW CONFIDENCE DETAILS OF ANY WEAK UPPER DISTURBANCES MOVING OVERHEAD THE ZEPHYR MAY BE PERIODICALLY ENHANCED WITH AN INCREASED FIRE CONCERN. SNYDER AVIATION... AN UPPER DISTURBANCE, CURRENTLY LOCATED NEAR KAAT, IS MOVING AROUND THE LARGE UPPER TROUGH CENTERED OVER THE NORTHERN ROCKIES. THE DISTURBANCE IS EXPECTED TO KICK OFF A FEW LIGHT SHOWERS NORTH AND EAST OF KRNO, WITH A FEW THUNDERSTORMS POSSIBLE EAST AND NORTH OF A GERLACH TO PYRAMID LAKE TO KNFL LINE THROUGH SUNSET. BRIEF HIGHER TERRAIN OBSCURATION, SMALL HAIL (LESS THAN HALF-INCH) AND WIND GUSTS TO AROUND 30 KTS COULD ACCOMPANY ANY THUNDERSTORMS. LATE TONIGHT, THE MARTIS VALLEY NEAR KTRK COULD SEE PATCHY FOG. OTHERWISE, VFR CONDITIONS WITH MAINLY LIGHT WINDS (LESS THAN 8 KTS) WILL RETURN OVERNIGHT AND FOR WEDNESDAY AS HIGH PRESSURE BUILDS INTO CALIFORNIA. SNYDER && .REV WATCHES/WARNINGS/ADVISORIES... NV...NONE. CA...NONE. && $$ FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT... HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
923 PM MDT TUE JUN 17 2014 UPDATED FIRE WEATHER SECTION .UPDATE... ISSUED AT 712 PM MDT TUE JUN 17 2014 WITH THE FRONT HAVING MOVED INTO THE UINTA BASIN...UPDATED THE FORECAST FOR NORTHEAST UTAH. TEMPS IN EXTREME SW WYOMING HAS FALLEN INTO THE 30S WITH SNOW AT EVANSTON. REMOTE SENSORS IN DAGGETT COUNTY SHOWING TEMPS HAVE DROPPED INTO THE 30S. APPEARS TO BE A WET ROAD ON HWY 191 PER UDOT WEB CAM...BUT IF CURRENT TREND HOLDS...THEN SNOW IS ABOUT TO BEGIN AND UPDATED THE WSW TO REFLECT THIS. ELSEWHERE...THE RAP MODEL SHOWS THE BAROCLINIC ZONE WEAKENING AS THE FRONT MOVES ACROSS MOFFAT COUNTY IN NW COLORADO. THE SNOW OVER THE UINTA MOUNTAINS MAY NOT MAKE IT TO THE ELKHEADS OR PARK RANGE. CURRENT FORECAST TRENDS APPEAR ON TRACK AND NO OTHER UPDATES NEEDED. && .SHORT TERM...(TONIGHT THROUGH WEDNESDAY NIGHT) ISSUED AT 400 PM MDT TUE JUN 17 2014 STRONG SOUTHWEST WINDS OBSERVED ACROSS THE FORECAST AREA TODAY AHEAD OF COLD FRONT OVER NORTHEAST UTAH STRETCHING FROM EAST OF KRKS-KMLF AT 21Z. MAGNITUDE OF WINDS FROM 20 TO 30 MPH ACROSS MOST VALLEY LOCATIONS WITH GUSTS FROM 45 TO 50 MPH. SO FAR...NO CONVECTIVE ACTIVITY OUT AHEAD OF THE FRONT AS MOISTURE RELATIVELY LIMITED IN ADVANCE OF THE SYSTEM. NOCTURNAL COOLING WILL ALLOW WINDS TO DECOUPLE OVER THE VALLEYS LATER THIS EVENING BUT WILL CONTINUE TO BLOW PRETTY HARD UNTIL THEN SO WILL HOLD ONTO WIND ADVISORY THROUGH 9 PM. LATEST SHORT-RANGE MODELS INDICATED THE FRONT WILL PASS THROUGH KVEL AND INTO EXTREME NORTHWEST COLORADO BY 6 PM. EXPECT SHOWERS AND ISOLATED THUNDERSTORMS WILL BE CONFINED TO AREAS ALONG AND BEHIND THE FRONT SO CUT BACK POPS SOUTHEAST OF THE BOUNDARY THIS EVENING. SNOW LEVEL LOWERS RAPIDLY OVER THE EASTERN UINTAS BEHIND THE STRONG FRONT SO RAIN LOWER TO AROUND 8000 FEET STILL LOOKS REASONABLE. FRONT PROGGED TO CONTINUE SLOWLY SOUTHEAST THROUGH THE NIGHT REACHING ROUGHLY A KEGE TO KPGA LINE BY MORNING. AGAIN... PRECIPITATION CONFINED TO AREAS BEHIND THE FRONT WITH NORTHEAST UTAH AND THE NORTHWEST CORNER OF COLORADO FAVORED. LATEST NAM12 CONTINUED TO GENERATE DECENT ACCUMULATIONS OVER THE EASTERN UINTA MOUNTAINS FOR MID JUNE SO WILL CONTINUE WINTER WEATHER ADVISORY THROUGH MIDDAY WEDNESDAY. SHORTWAVE ROTATING THROUGH THE BASE OF THE TROUGH WILL DRIVE THE FRONT ACROSS THE REMAINDER OF THE FORECAST AREA WEDNESDAY AFTERNOON. PASSAGE OF THE WAVE CORRESPONDS WITH PEAK HEATING SO EXPECT GOOD SHOWER AND THUNDERSTORM COVERAGE OVER THE MOUNTAINS AND ADJACENT VALLEYS. COLDEST AIR STAYS NORTH SO SNOW LEVELS AT OR ABOVE 10K FEET AND LITTLE IMPACT ON HIGH PASSES EXPECTED. EMBEDDED THUNDERSTORMS COULD BRING DOWN STRONG WINDS ALOFT...BUT OTHERWISE LESS WINDY THAN TODAY. MUCH COOLER BEHIND THE FRONT WITH HIGHS DROPPING BY 10 TO 15 DEGREES FOR MOST AREAS. PRECIPITATION ENDS PRETTY ABRUPTLY WEDNESDAY EVENING AS SUBSIDENCE ...COOLING...AND DRYING WORK ACROSS THE AREA. CLEARING SKIES WILL LEAD TO SOME COLD OVERNIGHT LOWS. THUS FAR APPEARS ONLY PORTIONS OF NORTHWEST COLORADO UNDER THE THREAT OF LATE SEASON FREEZE WHICH COULD IMPACT SENSITIVE VEGETATION. THEREFORE...HOISTED A FREEZE WATCH FOR THE AREA FROM MIDNIGHT TO 9 AM THURSDAY MORNING. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 400 PM MDT TUE JUN 17 2014 A COOL THURSDAY MORNING WITH NEAR OR BELOW FREEZING TEMPERATURES IN SOME MOUNTAIN AREAS WILL EVOLVE INTO AN UNSEASONABLY COOL AFTERNOON... WITH HIGH TEMPERATURES IN THE VALLEYS STRUGGLING TO GET TO 80 DEGREES. HOWEVER...THROUGHOUT THE DAY WARMER AIR ALOFT WILL ADVECT INTO THE REGION AS THE UPPER LEVEL TROUGH EXITS AND RIDGING MOVES OVER EASTERN UTAH AND WESTERN COLORADO. HIGH PRESSURE WILL REMAIN OVERHEAD THROUGH EARLY NEXT WEEK ALLOWING TEMPERATURES TO REBOUND BACK TO AND ABOVE NORMAL. MOISTURE ALONG THE FRONT RANGE WILL REGRESS WEST TOWARD THE DIVIDE ON SUNDAY EVENING...BRINGING THE POSSIBILITY OF DIURNALLY DRIVEN MOUNTAIN CONVECTION ALONG THE CENTRAL MOUNTAINS SUNDAY THROUGH TUESDAY. ELSEWHERE WILL STAY DRY WITH LIGHT DIURNALLY DRIVEN WINDS. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING) ISSUED AT 549 PM MDT TUE JUN 17 2014 MODERATE MECHANICAL TURBULENCE AND WITH SURFACE WINDS 22020G35KT WILL CONTINUE THROUGH 02Z-03Z THIS EVENING...BUT DIMINISH OVERNIGHT. COLD FRONT OVER NE UTAH WILL SWEEP ACROSS WRN COLORADO LATE TONIGHT AND WEDNESDAY MORNING. LOCAL SURFACE WIND OF G25-30KTS IS EXPECTED WEDNESDAY AFTERNOON. TURBULENCE WILL BE LESS...BUT STILL EXPECT SOME MODERATE CHOP. NE UTAH/WRN COLORADO...SCT -SHRA/ISOLD -TSRA OVER NE UTAH WITH SNOW LEVEL LOWERING TO 8K FEET WILL SPREAD INTO NW COLORADO TONIGHT. MOUNTAINS MAY BECOME OBSCURED AS THE FRONT CROSSES THE REGION TONIGHT. SCT -SHRA/ISOLD -TSRA WILL SPREAD ACROSS THE HIGHER TERRAIN OF WRN COLORADO ON WEDNESDAY. && .FIRE WEATHER... ISSUED AT 922 PM MDT TUE JUN 17 2014 THE RED FLAG WARNING FOR TODAY WAS ALLOWED TO EXPIRE AT 900 PM...THOUGH LOCALIZED POCKETS OF CRITICAL WIND/HUMIDITY MAY PERSIST FOR ANOTHER HOUR OR SO IN ZONES 203...290...292...207 AHEAD OF A COLD FRONT. HOWEVER...A RED FLAG WARNING REMAINS IN EFFECT FOR FIRE WEATHER ZONE 207 BELOW 9500 FEET ON WEDNESDAY BETWEEN NOON AND 700 PM FOR CONTINUE GUSTY WEST TO SOUTHWEST WINDS AND LOW HUMIDITY. THE COLD FRONT SHOULD EVENTUALLY CLEAR THE AREA WEDNESDAY EVENING...AND WINDS ARE EXPECTED TO DECREASE BEHIND THIS FRONTAL PASSAGE. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...RED FLAG WARNING FROM NOON TO 7 PM MDT WEDNESDAY FOR COZ207. FREEZE WATCH FROM LATE WEDNESDAY NIGHT THROUGH THURSDAY MORNING FOR COZ002. UT...WINTER WEATHER ADVISORY UNTIL NOON MDT WEDNESDAY FOR UTZ023. && $$ UPDATE...PF SHORT TERM...NL LONG TERM...JAM AVIATION...PF FIRE WEATHER...JAD
AREA FORECAST DISCUSSION
NWS PUEBLO CO
856 PM MDT TUE JUN 17 2014 .UPDATE... ISSUED AT 855 PM MDT TUE JUN 17 2014 RED FLAG WARNING ALLOWED TO EXPIRE FOR TONIGHT. CONDITIONS HAVE SUBSIDED BELOW CRITICAL FIRE WEATHER LEVELS. ALSO...LOADED IN LATEST OBSERVATIONS. LW UPDATE ISSUED AT 651 PM MDT TUE JUN 17 2014 LOADED IN LATEST OBSERVATIONS. NO OTHER CHANGES TO FORECAST AT THIS TIME. LW && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 247 PM MDT TUE JUN 17 2014 .SHORT TERM...(TONIGHT AND TOMORROW) CURRENTLY...THE UPPER LOW WAS LOCATED OVER IDAHO THIS AFTN...PRODUCING STRONG SW FLOW ALOFT ACROSS THE 4 CORNERS AND COLORADO. THERE IS SLIGHTLY MORE MOISTURE AVAILABLE AS EVIDENCED BY A BIT MORE CU OVER THE MTS...BUT FOR THE MOST PART TODAY WAS VERY SIMILAR TO YESTERDAY WITH STRONG W-SW WINDS WITH GUSTS OF 35-45 MPH...SINGLE DIGIT RH READINGS AND MAX TEMPS IN THE UPPER 80S TO MID 90S FOR THE PLAINS...AND AROUND 80 F FOR THE HIGH VALLEYS. TONIGHT AND TOMORROW...THE UPPER SYSTEM IS FORECAST TO TRACK EAST ACROSS THE NORTHERN ROCKIES OVER THE NEXT 24 HRS...WITH A TIGHTENING OF THE PRES GRADIENT AND MOISTURE EDIFICATION EXPECTED LATE TONIGHT THROUGH WED. MODELS HAD INITIALLY HINTED AT SOME ISOLATED CONVECTION OVER THE SOUTHERN MES THIS EVE...BUT LATEST RADAR AND SATELLITE TRENDS AS WELL AS THE LATEST HRRR RUN POINTS TO A DRY NIGHT. THEREFORE...PULLED POPS TONIGHT. ONGOING FORKS HIGHLIGHTS FOR TONIGHT LOOK GOOD...AND WILL SHUT DOWN AT 9 PM. AS FOR TOMORROW...DECIDED TO UPGRADE THE WATCH TO A RED FLAG WARNING FOR EL PASO AND FREMONT COUNTIES SINCE THOSE ARE THE ONLY AREAS THAT REPORT RECEPTIVE FUELS. ANOTHER WINDY...HOT AND DRY DAY IS EXPECTED...BUT ISOLATED CONVECTION IS FORECAST TO START DEVELOPING OVER THE HIGHER TERRAIN BY LATE MORNING...AND OVER THE FAR EASTERN PLAINS TOMORROW AFN. ONE OR TWO OF THE STORMS OVER THE FAR SE CORNER WILL HAVE FAVORABLE SHEAR AND ENOUGH LLVL MOISTURE ON TAP TO BECOME STRONG. LOOK FOR MAX TEMPS ONCE AGAIN TO BE IN THE 90S FOR THE E PLAINS...AND MID TO UPPER 70S FOR THE HIGH VALLEYS. MOOR .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 247 PM MDT TUE JUN 17 2014 ...WETTER CONDITIONS POSSIBLE LATE WEEKEND INTO EARLY NEXT WEEK... ...ISOLD SVR THREAT POSSIBLE EARLY TOMORROW EVENING OVER FAR SE CO... STRONG SOUTHWEST FLOW ALOFT AT THE BEGINNING OF THIS PERIOD WILL GRADUALLY TRANSITION TO LIGHT WESTERLY FLOW AND THEN A VERY WEAK FLOW PATTERN BY EARLY NEXT WEEK. THIS PATTERN WILL SHOULD ALLOW FOR A WETTER PATTERN FOR THE REGION...ESPECIALLY LATE WEEKEND INTO EARLY NEXT WEEK. WED NITE... THERE IS A SLIGHT CHANCE THAT WE MAY SEE A STRONG STORM OVER THE FAR SE PLAINS ON THIS DAY AS THE DRYLINE WILL BE OVER THE REGION. MAIN CONCERN WILL BE STRONG GUSTY WINDS AND LIGHTNING WHICH WILL HAVE THE POTENTIAL TO CAUSE A GRASS FIRE DUE TO THE GUSTY SYNOPTIC S-SW WINDS. HOWEVER...I SHOULD NOTE...THAT THE LATEST 18Z NAM HINTS AT THE DRYLINE RETROGRADING BACK WEST OVER FAR SE CO. SFC WINDS SHIFT TO SOUTHEAST AND EHI AND STP RAPIDLY INCREASE ALONG THE CO/KS BORDER. THIS AREA WILL HAVE TO BE WATCHED CAREFULLY. LATE WED EVENING...A COOL FRONT WILL COME DOWN THE PLAINS. BEST CHANCE OF ANY POPS WITH THIS BOUNDARY WILL BE OVER THE E PLAINS...WHILE THE REST OF THE REGION SHOULD REMAIN DRY. THURSDAY... COOLER UPSLOPE FLOW WILL BE OVER THE REGION. HOWEVER...LLVL ATMOS WILL BE ON THE DRY SIDE SO NOT EXPECTING MUCH IN THE WAY OF ANY SIGNIFICANT CONVECTION. ANY CONVECTION THAT DEVELOPS WILL LIKELY BE LATE IN THE DAY OVER THE RATON MESA REGION AND MAYBE THE E SLOPES OF THE S MTNS. MAX TEMPS THU SHOULD BE ABOUT 4-8F COOLER ON THE PLAINS AS COMPARED TO WED MAXES. FRIDAY... WEAK DISTURBANCES ALOFT WILL MOVE OVER THE REGION AS THE FLOW ALOFT CONTINUES TO WEAKEN. OVERALL EXPECT IT TO REMAIN DRY...WITH ONLY ISOLD POPS OVER THE S MTNS AND POSSIBLY FAR E PLAINS. TEMPS WILL WARM BACK UP INTO THE U80S/L90S PLAINS. SATURDAY... LLVL MOISTURE WILL GRADUALLY INCREASE OVER THE PLAINS ON THIS DAY. EC IS MORE ROBUST WITH THIS MOISTURE THAN GFS...AND BREAKS OUT CONVECTION ALL AREAS...ESPECIALLY PALMER DVD REGION. MAX TEMPS SHOULD BE ABOUT A DEGREE OR TWO WARMER THAN FRI OVER THE PLAINS. SUNDAY... MOISTURE CONTINUES TO INCREASE OVER THE PLAINS AS CANADIAN HIGH PRESSURE BUILD SWD AND SEVERAL UPPER LVL DISTURBANCES MOVER OVER THE REGION IN THE WEAK ZONAL FLOW. MOISTURE MAY WORK A BIT FARTHER WEST INTO THE MTNS...ESPECIALLY C /MTNS AREA. ALL GUIDANCE HAS SOME HEALTHY QPF CONVECTIVE BULLSEYES OVER THE PLAINS...ESPECIALLY OVER THE PALMER DVD REGION. LIKEWISE...EXPECT A BETTER CHANCE OF SHOWERS AND STORMS OVER THE PLAINS ON THIS DAY WITH A BIT COOLER AFTERNOON TEMPS. WITH THE INCREASING MSTR AND WEAKER FLOW ALOFT...THE FLASH FLOOD THREAT OVER THE BURN SCARS WILL BE INCREASING. MONDAY AND TUESDAY... NOT MUCH CHANGE IN THE PATTERN AS FLOW ALOFT WILL BE FROM THE NW AND GENERALLY WEAK. SEVERAL DISTURBANCES WILL MOVE THROUGH THIS FLOW AND AFTERNOON AND EVENING ROUNDS OF CONVECTION ARE LIKELY OVER THE MTNS ADJ TO THE PLAINS...WITH THE CONVECTION MOVING INTO THE FAR E PLAINS DURING THE EVENING HOURS. TEMPS WILL BE ON THE COOL SIDE WITH THE CLOUDS AND MSTR OVER THE REGION. PERIODS OF HEAVY RAIN WILL BE POSSIBLE AND THE FLASH FLOOD CONCERNS WILL CONTINUE INTO EARLY NEXT WEEK OVER THE SCARS. OVERALL...THE INTERIOR MTNS WILL LIKELY REMAIN ON THE DRY SIDE DURING THIS PERIOD...WITH GRADUALLY INCREASING MSTR LATER IN THE PERIOD. THIS WILL ALLOW FOR THE INTERIOR MTNS TO CONTINUE TO DRY OUT WITH TIME. /HODANISH && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 247 PM MDT TUE JUN 17 2014 VFR CONDITIONS ARE EXPECTED OVER THE NEXT 24 HRS FOR THE THREE MAIN TAF SITES OF KCOS...KPUB AND KALS. STRONG SW WINDS WITH GUSTS OF 30- 40 KTS WILL BE POSSIBLE THIS EVENING UNTIL 02-03Z...THEN START UP AGAIN TOMORROW MORNING AFTER 16Z. THESE WIND GUSTS WILL CREATE AREAS OF BLOWING DUST AND REDUCED VISIBILITIES AT TIMES. MOORE && .FIRE WEATHER... ISSUED AT 855 PM MDT TUE JUN 17 2014 RED FLAG WARNING ALLOWED TO EXPIRE FOR TONIGHT. CONDITIONS HAVE SUBSIDED BELOW CRITICAL FIRE WEATHER LEVELS. && .PUB WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING UNTIL 9 PM MDT THIS EVENING FOR COZ222-225>227. RED FLAG WARNING FROM NOON TO 8 PM MDT WEDNESDAY FOR COZ222-226- 227. && $$ UPDATE...LW SHORT TERM...MOORE LONG TERM...HODANISH AVIATION...MOORE FIRE WEATHER...LW
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
712 PM MDT TUE JUN 17 2014 .UPDATE... ISSUED AT 712 PM MDT TUE JUN 17 2014 WITH THE FRONT HAVING MOVED INTO THE UINTA BASIN...UPDATED THE FORECAST FOR NORTHEAST UTAH. TEMPS IN EXTREME SW WYOMING HAS FALLEN INTO THE 30S WITH SNOW AT EVANSTON. REMOTE SENSORS IN DAGGETT COUNTY SHOWING TEMPS HAVE DROPPED INTO THE 30S. APPEARS TO BE A WET ROAD ON HWY 191 PER UDOT WEB CAM...BUT IF CURRENT TREND HOLDS...THEN SNOW IS ABOUT TO BEGIN AND UPDATED THE WSW TO REFLECT THIS. ELSEWHERE...THE RAP MODEL SHOWS THE BAROCLINIC ZONE WEAKENING AS THE FRONT MOVES ACROSS MOFFAT COUNTY IN NW COLORADO. THE SNOW OVER THE UINTA MOUNTAINS MAY NOT MAKE IT TO THE ELKHEADS OR PARK RANGE. CURRENT FORECAST TRENDS APPEAR ON TRACK AND NO OTHER UPDATES NEEDED. && .SHORT TERM...(TONIGHT THROUGH WEDNESDAY NIGHT) ISSUED AT 400 PM MDT TUE JUN 17 2014 STRONG SOUTHWEST WINDS OBSERVED ACROSS THE FORECAST AREA TODAY AHEAD OF COLD FRONT OVER NORTHEAST UTAH STRETCHING FROM EAST OF KRKS-KMLF AT 21Z. MAGNITUDE OF WINDS FROM 20 TO 30 MPH ACROSS MOST VALLEY LOCATIONS WITH GUSTS FROM 45 TO 50 MPH. SO FAR...NO CONVECTIVE ACTIVITY OUT AHEAD OF THE FRONT AS MOISTURE RELATIVELY LIMITED IN ADVANCE OF THE SYSTEM. NOCTURNAL COOLING WILL ALLOW WINDS TO DECOUPLE OVER THE VALLEYS LATER THIS EVENING BUT WILL CONTINUE TO BLOW PRETTY HARD UNTIL THEN SO WILL HOLD ONTO WIND ADVISORY THROUGH 9 PM. LATEST SHORT-RANGE MODELS INDICATED THE FRONT WILL PASS THROUGH KVEL AND INTO EXTREME NORTHWEST COLORADO BY 6 PM. EXPECT SHOWERS AND ISOLATED THUNDERSTORMS WILL BE CONFINED TO AREAS ALONG AND BEHIND THE FRONT SO CUT BACK POPS SOUTHEAST OF THE BOUNDARY THIS EVENING. SNOW LEVEL LOWERS RAPIDLY OVER THE EASTERN UINTAS BEHIND THE STRONG FRONT SO RAIN LOWER TO AROUND 8000 FEET STILL LOOKS REASONABLE. FRONT PROGGED TO CONTINUE SLOWLY SOUTHEAST THROUGH THE NIGHT REACHING ROUGHLY A KEGE TO KPGA LINE BY MORNING. AGAIN... PRECIPITATION CONFINED TO AREAS BEHIND THE FRONT WITH NORTHEAST UTAH AND THE NORTHWEST CORNER OF COLORADO FAVORED. LATEST NAM12 CONTINUED TO GENERATE DECENT ACCUMULATIONS OVER THE EASTERN UINTA MOUNTAINS FOR MID JUNE SO WILL CONTINUE WINTER WEATHER ADVISORY THROUGH MIDDAY WEDNESDAY. SHORTWAVE ROTATING THROUGH THE BASE OF THE TROUGH WILL DRIVE THE FRONT ACROSS THE REMAINDER OF THE FORECAST AREA WEDNESDAY AFTERNOON. PASSAGE OF THE WAVE CORRESPONDS WITH PEAK HEATING SO EXPECT GOOD SHOWER AND THUNDERSTORM COVERAGE OVER THE MOUNTAINS AND ADJACENT VALLEYS. COLDEST AIR STAYS NORTH SO SNOW LEVELS AT OR ABOVE 10K FEET AND LITTLE IMPACT ON HIGH PASSES EXPECTED. EMBEDDED THUNDERSTORMS COULD BRING DOWN STRONG WINDS ALOFT...BUT OTHERWISE LESS WINDY THAN TODAY. MUCH COOLER BEHIND THE FRONT WITH HIGHS DROPPING BY 10 TO 15 DEGREES FOR MOST AREAS. PRECIPITATION ENDS PRETTY ABRUPTLY WEDNESDAY EVENING AS SUBSIDENCE ...COOLING...AND DRYING WORK ACROSS THE AREA. CLEARING SKIES WILL LEAD TO SOME COLD OVERNIGHT LOWS. THUS FAR APPEARS ONLY PORTIONS OF NORTHWEST COLORADO UNDER THE THREAT OF LATE SEASON FREEZE WHICH COULD IMPACT SENSITIVE VEGETATION. THEREFORE...HOISTED A FREEZE WATCH FOR THE AREA FROM MIDNIGHT TO 9 AM THURSDAY MORNING. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 400 PM MDT TUE JUN 17 2014 A COOL THURSDAY MORNING WITH NEAR OR BELOW FREEZING TEMPERATURES IN SOME MOUNTAIN AREAS WILL EVOLVE INTO AN UNSEASONABLY COOL AFTERNOON... WITH HIGH TEMPERATURES IN THE VALLEYS STRUGGLING TO GET TO 80 DEGREES. HOWEVER...THROUGHOUT THE DAY WARMER AIR ALOFT WILL ADVECT INTO THE REGION AS THE UPPER LEVEL TROUGH EXITS AND RIDGING MOVES OVER EASTERN UTAH AND WESTERN COLORADO. HIGH PRESSURE WILL REMAIN OVERHEAD THROUGH EARLY NEXT WEEK ALLOWING TEMPERATURES TO REBOUND BACK TO AND ABOVE NORMAL. MOISTURE ALONG THE FRONT RANGE WILL REGRESS WEST TOWARD THE DIVIDE ON SUNDAY EVENING...BRINGING THE POSSIBILITY OF DIURNALLY DRIVEN MOUNTAIN CONVECTION ALONG THE CENTRAL MOUNTAINS SUNDAY THROUGH TUESDAY. ELSEWHERE WILL STAY DRY WITH LIGHT DIURNALLY DRIVEN WINDS. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING) ISSUED AT 549 PM MDT TUE JUN 17 2014 MODERATE MECHANICAL TURBULENCE AND WITH SURFACE WINDS 22020G35KT WILL CONTINUE THROUGH 02Z-03Z THIS EVENING...BUT DIMINISH OVERNIGHT. COLD FRONT OVER NE UTAH WILL SWEEP ACROSS WRN COLORADO LATE TONIGHT AND WEDNESDAY MORNING. LOCAL SURFACE WIND OF G25-30KTS IS EXPECTED WEDNESDAY AFTERNOON. TURBULENCE WILL BE LESS...BUT STILL EXPECT SOME MODERATE CHOP. NE UTAH/WRN COLORADO...SCT -SHRA/ISOLD -TSRA OVER NE UTAH WITH SNOW LEVEL LOWERING TO 8K FEET WILL SPREAD INTO NW COLORADO TONIGHT. MOUNTAINS MAY BECOME OBSCURED AS THE FRONT CROSSES THE REGION TONIGHT. SCT -SHRA/ISOLD -TSRA WILL SPREAD ACROSS THE HIGHER TERRAIN OF WRN COLORADO ON WEDNESDAY. && .FIRE WEATHER... ISSUED AT 400 PM MDT TUE JUN 17 2014 WIDESPREAD CRITICAL FIRE WEATHER CONDITIONS WILL CONTINUE THROUGH TONIGHT DUE TO STRONG SOUTHWEST FLOW AHEAD OF AN APPROACHING COLD FRONT. RED FLAG WARNINGS ARE IN EFFECT FOR MUCH OF WESTERN COLORADO UNTIL 9 PM MDT THIS EVENING. WIND GUSTS UP TO 50 MPH ARE LIKELY THROUGHOUT THE EVENING WITH HUMIDITY VALUES IN THE 5 TO 15 PERCENT RANGE. ANOTHER RED FLAG WARNING HAS BEEN ISSUED FOR FIRE WEATHER ZONE 207 BELOW 9500 FEET ON WEDNESDAY BETWEEN NOON AND 7PM. ON WEDNESDAY...THE COLD FRONT WILL PASS THROUGH WESTERN COLORADO AND SOUTHEASTERN UTAH. WINDS ARE EXPECTED TO DECREASE BEHIND THIS FRONTAL PASSAGE. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...WIND ADVISORY UNTIL 9 PM MDT THIS EVENING FOR COZ001-002-006>008- 011-020>022. RED FLAG WARNING UNTIL 9 PM MDT THIS EVENING FOR COZ200-202-203- 207-290-292-293. RED FLAG WARNING FROM NOON TO 7 PM MDT WEDNESDAY FOR COZ207. FREEZE WATCH FROM LATE WEDNESDAY NIGHT THROUGH THURSDAY MORNING FOR COZ002. UT...WIND ADVISORY UNTIL 9 PM MDT THIS EVENING FOR UTZ022-027-029. WINTER WEATHER ADVISORY UNTIL NOON MDT WEDNESDAY FOR UTZ023. && $$ UPDATE...PF SHORT TERM...NL LONG TERM...JAM AVIATION...PF FIRE WEATHER...JAM
AREA FORECAST DISCUSSION
NWS PUEBLO CO
659 PM MDT TUE JUN 17 2014 .UPDATE... ISSUED AT 651 PM MDT TUE JUN 17 2014 LOADED IN LATEST OBSERVATIONS. NO OTHER CHANGES TO FORECAST AT THIS TIME. LW && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 247 PM MDT TUE JUN 17 2014 .SHORT TERM...(TONIGHT AND TOMORROW) CURRENTLY...THE UPPER LOW WAS LOCATED OVER IDAHO THIS AFTN...PRODUCING STRONG SW FLOW ALOFT ACROSS THE 4 CORNERS AND COLORADO. THERE IS SLIGHTLY MORE MOISTURE AVAILABLE AS EVIDENCED BY A BIT MORE CU OVER THE MTS...BUT FOR THE MOST PART TODAY WAS VERY SIMILAR TO YESTERDAY WITH STRONG W-SW WINDS WITH GUSTS OF 35-45 MPH...SINGLE DIGIT RH READINGS AND MAX TEMPS IN THE UPPER 80S TO MID 90S FOR THE PLAINS...AND AROUND 80 F FOR THE HIGH VALLEYS. TONIGHT AND TOMORROW...THE UPPER SYSTEM IS FORECAST TO TRACK EAST ACROSS THE NORTHERN ROCKIES OVER THE NEXT 24 HRS...WITH A TIGHTENING OF THE PRES GRADIENT AND MOISTURE EDIFICATION EXPECTED LATE TONIGHT THROUGH WED. MODELS HAD INITIALLY HINTED AT SOME ISOLATED CONVECTION OVER THE SOUTHERN MES THIS EVE...BUT LATEST RADAR AND SATELLITE TRENDS AS WELL AS THE LATEST HRRR RUN POINTS TO A DRY NIGHT. THEREFORE...PULLED POPS TONIGHT. ONGOING FORKS HIGHLIGHTS FOR TONIGHT LOOK GOOD...AND WILL SHUT DOWN AT 9 PM. AS FOR TOMORROW...DECIDED TO UPGRADE THE WATCH TO A RED FLAG WARNING FOR EL PASO AND FREMONT COUNTIES SINCE THOSE ARE THE ONLY AREAS THAT REPORT RECEPTIVE FUELS. ANOTHER WINDY...HOT AND DRY DAY IS EXPECTED...BUT ISOLATED CONVECTION IS FORECAST TO START DEVELOPING OVER THE HIGHER TERRAIN BY LATE MORNING...AND OVER THE FAR EASTERN PLAINS TOMORROW AFN. ONE OR TWO OF THE STORMS OVER THE FAR SE CORNER WILL HAVE FAVORABLE SHEAR AND ENOUGH LLVL MOISTURE ON TAP TO BECOME STRONG. LOOK FOR MAX TEMPS ONCE AGAIN TO BE IN THE 90S FOR THE E PLAINS...AND MID TO UPPER 70S FOR THE HIGH VALLEYS. MOOR .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 247 PM MDT TUE JUN 17 2014 ...WETTER CONDITIONS POSSIBLE LATE WEEKEND INTO EARLY NEXT WEEK... ...ISOLD SVR THREAT POSSIBLE EARLY TOMORROW EVENING OVER FAR SE CO... STRONG SOUTHWEST FLOW ALOFT AT THE BEGINNING OF THIS PERIOD WILL GRADUALLY TRANSITION TO LIGHT WESTERLY FLOW AND THEN A VERY WEAK FLOW PATTERN BY EARLY NEXT WEEK. THIS PATTERN WILL SHOULD ALLOW FOR A WETTER PATTERN FOR THE REGION...ESPECIALLY LATE WEEKEND INTO EARLY NEXT WEEK. WED NITE... THERE IS A SLIGHT CHANCE THAT WE MAY SEE A STRONG STORM OVER THE FAR SE PLAINS ON THIS DAY AS THE DRYLINE WILL BE OVER THE REGION. MAIN CONCERN WILL BE STRONG GUSTY WINDS AND LIGHTNING WHICH WILL HAVE THE POTENTIAL TO CAUSE A GRASS FIRE DUE TO THE GUSTY SYNOPTIC S-SW WINDS. HOWEVER...I SHOULD NOTE...THAT THE LATEST 18Z NAM HINTS AT THE DRYLINE RETROGRADING BACK WEST OVER FAR SE CO. SFC WINDS SHIFT TO SOUTHEAST AND EHI AND STP RAPIDLY INCREASE ALONG THE CO/KS BORDER. THIS AREA WILL HAVE TO BE WATCHED CAREFULLY. LATE WED EVENING...A COOL FRONT WILL COME DOWN THE PLAINS. BEST CHANCE OF ANY POPS WITH THIS BOUNDARY WILL BE OVER THE E PLAINS...WHILE THE REST OF THE REGION SHOULD REMAIN DRY. THURSDAY... COOLER UPSLOPE FLOW WILL BE OVER THE REGION. HOWEVER...LLVL ATMOS WILL BE ON THE DRY SIDE SO NOT EXPECTING MUCH IN THE WAY OF ANY SIGNIFICANT CONVECTION. ANY CONVECTION THAT DEVELOPS WILL LIKELY BE LATE IN THE DAY OVER THE RATON MESA REGION AND MAYBE THE E SLOPES OF THE S MTNS. MAX TEMPS THU SHOULD BE ABOUT 4-8F COOLER ON THE PLAINS AS COMPARED TO WED MAXES. FRIDAY... WEAK DISTURBANCES ALOFT WILL MOVE OVER THE REGION AS THE FLOW ALOFT CONTINUES TO WEAKEN. OVERALL EXPECT IT TO REMAIN DRY...WITH ONLY ISOLD POPS OVER THE S MTNS AND POSSIBLY FAR E PLAINS. TEMPS WILL WARM BACK UP INTO THE U80S/L90S PLAINS. SATURDAY... LLVL MOISTURE WILL GRADUALLY INCREASE OVER THE PLAINS ON THIS DAY. EC IS MORE ROBUST WITH THIS MOISTURE THAN GFS...AND BREAKS OUT CONVECTION ALL AREAS...ESPECIALLY PALMER DVD REGION. MAX TEMPS SHOULD BE ABOUT A DEGREE OR TWO WARMER THAN FRI OVER THE PLAINS. SUNDAY... MOISTURE CONTINUES TO INCREASE OVER THE PLAINS AS CANADIAN HIGH PRESSURE BUILD SWD AND SEVERAL UPPER LVL DISTURBANCES MOVER OVER THE REGION IN THE WEAK ZONAL FLOW. MOISTURE MAY WORK A BIT FARTHER WEST INTO THE MTNS...ESPECIALLY C /MTNS AREA. ALL GUIDANCE HAS SOME HEALTHY QPF CONVECTIVE BULLSEYES OVER THE PLAINS...ESPECIALLY OVER THE PALMER DVD REGION. LIKEWISE...EXPECT A BETTER CHANCE OF SHOWERS AND STORMS OVER THE PLAINS ON THIS DAY WITH A BIT COOLER AFTERNOON TEMPS. WITH THE INCREASING MSTR AND WEAKER FLOW ALOFT...THE FLASH FLOOD THREAT OVER THE BURN SCARS WILL BE INCREASING. MONDAY AND TUESDAY... NOT MUCH CHANGE IN THE PATTERN AS FLOW ALOFT WILL BE FROM THE NW AND GENERALLY WEAK. SEVERAL DISTURBANCES WILL MOVE THROUGH THIS FLOW AND AFTERNOON AND EVENING ROUNDS OF CONVECTION ARE LIKELY OVER THE MTNS ADJ TO THE PLAINS...WITH THE CONVECTION MOVING INTO THE FAR E PLAINS DURING THE EVENING HOURS. TEMPS WILL BE ON THE COOL SIDE WITH THE CLOUDS AND MSTR OVER THE REGION. PERIODS OF HEAVY RAIN WILL BE POSSIBLE AND THE FLASH FLOOD CONCERNS WILL CONTINUE INTO EARLY NEXT WEEK OVER THE SCARS. OVERALL...THE INTERIOR MTNS WILL LIKELY REMAIN ON THE DRY SIDE DURING THIS PERIOD...WITH GRADUALLY INCREASING MSTR LATER IN THE PERIOD. THIS WILL ALLOW FOR THE INTERIOR MTNS TO CONTINUE TO DRY OUT WITH TIME. /HODANISH && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 247 PM MDT TUE JUN 17 2014 VFR CONDITIONS ARE EXPECTED OVER THE NEXT 24 HRS FOR THE THREE MAIN TAF SITES OF KCOS...KPUB AND KALS. STRONG SW WINDS WITH GUSTS OF 30- 40 KTS WILL BE POSSIBLE THIS EVENING UNTIL 02-03Z...THEN START UP AGAIN TOMORROW MORNING AFTER 16Z. THESE WIND GUSTS WILL CREATE AREAS OF BLOWING DUST AND REDUCED VISIBILITIES AT TIMES. MOORE && .PUB WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING UNTIL 9 PM MDT THIS EVENING FOR COZ222-225>227. RED FLAG WARNING FROM NOON TO 8 PM MDT WEDNESDAY FOR COZ222-226- 227. && $$ UPDATE...LW SHORT TERM...MOORE LONG TERM...HODANISH AVIATION...MOORE
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1121 AM MDT MON JUN 16 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 247 AM MDT MON JUN 16 2014 MAIN CONCERN FOR TODAY IS THE EXPECTED CRITICAL FIRE WEATHER CONDITIONS. DRY WEST TO SW FLOW ALOFT WL BE OVR THE AREA TODAY AND PCPN IS NOT EXPECTED. SFC WINDS WL INCREASE IN ALL AREAS TODAY...WITH GUIDANCE INDICATING SUSTAINED AFTERNOON WINDS IN MOST AREAS OF 20 KTS OR HIGHER. HRRR AND RAP13 INDICATING AFTERNOON GUSTS OF 25-30 KTS OVR THE SERN PLAINS...AND AROUND 35 KTS IN THE SAN LUIS VALLEY. WITH WIND GUSTS THIS STRONG...WL ADD BLOWING DUST TO THE FORECAST FOR THE SERN PLAINS AND THE SAN LUIS VALLEY. LOCALIZED LOW VSBYS MAY DEVELOP THIS AFTERNOON DUE TO THE BLOWING DUST. WHEN THE WINDS PICK UP LATER TODAY...THE SFC DEW POINTS WL QUICKLY DRY OUT...AND MIN RH VALUES THIS AFTERNOON ARE EXPECTED TO BE BELOW 10 PERCENT OVR THE LOWER ELEVATIONS. THERE WL BE WIDESPREAD WEATHER CONDITIONS REACHING CRITICAL LEVELS WITH REGARDS TO FIRE WEATHER...HOWEVER THE ONLY AREA THAT CURRENTLY HAS FUELS THAT ARE CONSIDERED DRY...IS EL PASO COUNTY. THEREFORE THE ONLY LOCATION THAT WL BE COVERED WITH A RED FLAG WARNING IS EL PASO COUNTY. HIGH TEMPS TODAY WL BE WARMER THAN YESTERDAY OVR THE SERN PLAINS...AND WL BE ABOUT 5-10 DEGREES ABOVE AVERAGE. THE SAN LUIS VALLEY SHOULD SEE HIGH AROUND AVERAGE. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 247 AM MDT MON JUN 16 2014 ...FIRE WEATHER CONCERNS EARLY IN PERIOD THEN MOISTENING UP FOR THE WEEKEND... METEOROLOGICAL CONDITIONS FAVORABLE FOR EXTREME FIRE BEHAVIOR WILL BE OVER THE REGION BOTH TUESDAY AND WEDNESDAY AS A TROUGH TO OUR NORTHWEST KEEPS HOT AND DRY SW FLOW OVER THE REGION. FOR NOW...FUELS ARE MOIST ALL AREAS EXCEPT EL PASO COUNTY. HOWEVER...IF FUELS DRY OUTTHEN RED FLAG CONDITIONS WILL LIKELY BE EXPANDED OVER THE AREA TUESDAY AND WEDNESDAY. FOR NOW...A FIRE WEATHER WATCH IS IN EFFECT TUESDAY FOR EL PASO COUNTY AND WILL LIKELY BE ISSUED FOR WEDNESDAY BY THE DAY SHIFT LATER TODAY. THERE IS A CHANCE AS THE TROUGH GETS CLOSER ON WED...THAT THE DRYLINE MAY BECOME ACTIVE OVER THE FAR E PLAINS. BOTH THE 00Z NAM AND EC HAVE A PRETTY POTENT DISTURBANCE MOVING ACROSS N CO AND THIS MAY ALLOW FOR ISOLD SVR TSRA OVER THE FAR E PLAINS. SPC HAS MENTIONED THIS IN THERE DAY3 OUTLOOK. LATEST 06Z NAM RUN HAS TROUGH EVEN SHARPER...AND THUS A BETTER CHANCE OF SOME STRONG THUNDER OVER THE FAR SE PLAINS OVERALL DRY WX EXPECTED THU AND FRI AS COOLER DRIER AIR MOVES IN BEHIND WED NIGHTS TROUGH PASSAGE. EC AND GFS HINT THAT THINGS SHOULD MOISTEN UP FOR THE WEEKEND...WITH EC MORE BULLISH ON PRECIP CHANCES. THIS INCREASING MOISTURE IS MAINLY BEING FORCED BY THE LOW LVLS (PATTERN ALOFT IS PRETTY FLAT)...AS CANADIAN HIGH PRESSURE BUILDS SOUTH AND SHUNTS HIGHER LLVL MOISTURE (50-60DWPT AIR) INTO THE REGION. FOR NOW...HAVE WIDESPREAD LOW END POPS OVER THE REGION...BUT THESE VALUES MAY NEED TO BE BUMPED UP...ESPECIALLY FOR SUNDAY...IF THE EC SOLUTION VERIFIES. /HODANISH && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1115 AM MDT MON JUN 16 2014 VFR CONDITIONS ARE EXPECTED OVER THE NEXT 24 HRS FOR THE THREE MAIN TAF SITES OF KCOS...KPUB AND KALS. STRONG SW WINDS WITH GUSTS OF 30-40 KTS WILL BE POSSIBLE INTO THE EVENING...THEN START UP AGAIN TOMORROW MORNING AFTER 16Z. THESE WIND GUSTS WILL CREATE AREAS OF BLOWING DUST AND REDUCED VISIBILITIES AT TIMES. IN ADDITION...SMOKE FROM WILDFIRES IN NW NEW MEXICO AND CENTRAL ARIZONA HAS MADE IT IN TO COLORADO DUE TO THE STRONG SW FLOW ALOFT. MOORE && .PUB WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING UNTIL 9 PM MDT THIS EVENING FOR COZ226-227. FIRE WEATHER WATCH FROM TUESDAY AFTERNOON THROUGH TUESDAY EVENING FOR COZ226-227. && $$ SHORT TERM...28 LONG TERM...HODANISH AVIATION...MOORE
AREA FORECAST DISCUSSION
NWS PUEBLO CO
259 AM MDT MON JUN 16 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 247 AM MDT MON JUN 16 2014 MAIN CONCERN FOR TODAY IS THE EXPECTED CRITICAL FIRE WEATHER CONDITIONS. DRY WEST TO SW FLOW ALOFT WL BE OVR THE AREA TODAY AND PCPN IS NOT EXPECTED. SFC WINDS WL INCREASE IN ALL AREAS TODAY...WITH GUIDANCE INDICATING SUSTAINED AFTERNOON WINDS IN MOST AREAS OF 20 KTS OR HIGHER. HRRR AND RAP13 INDICATING AFTERNOON GUSTS OF 25-30 KTS OVR THE SERN PLAINS...AND AROUND 35 KTS IN THE SAN LUIS VALLEY. WITH WIND GUSTS THIS STRONG...WL ADD BLOWING DUST TO THE FORECAST FOR THE SERN PLAINS AND THE SAN LUIS VALLEY. LOCALIZED LOW VSBYS MAY DEVELOP THIS AFTERNOON DUE TO THE BLOWING DUST. WHEN THE WINDS PICK UP LATER TODAY...THE SFC DEW POINTS WL QUICKLY DRY OUT...AND MIN RH VALUES THIS AFTERNOON ARE EXPECTED TO BE BELOW 10 PERCENT OVR THE LOWER ELEVATIONS. THERE WL BE WIDESPREAD WEATHER CONDITIONS REACHING CRITICAL LEVELS WITH REGARDS TO FIRE WEATHER...HOWEVER THE ONLY AREA THAT CURRENTLY HAS FUELS THAT ARE CONSIDERED DRY...IS EL PASO COUNTY. THEREFORE THE ONLY LOCATION THAT WL BE COVERED WITH A RED FLAG WARNING IS EL PASO COUNTY. HIGH TEMPS TODAY WL BE WARMER THAN YESTERDAY OVR THE SERN PLAINS...AND WL BE ABOUT 5-10 DEGREES ABOVE AVERAGE. THE SAN LUIS VALLEY SHOULD SEE HIGH AROUND AVERAGE. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 247 AM MDT MON JUN 16 2014 ...FIRE WEATHER CONCERNS EARLY IN PERIOD THEN MOISTENING UP FOR THE WEEKEND... METEOROLOGICAL CONDITIONS FAVORABLE FOR EXTREME FIRE BEHAVIOR WILL BE OVER THE REGION BOTH TUESDAY AND WEDNESDAY AS A TROUGH TO OUR NORTHWEST KEEPS HOT AND DRY SW FLOW OVER THE REGION. FOR NOW...FUELS ARE MOIST ALL AREAS EXCEPT EL PASO COUNTY. HOWEVER...IF FUELS DRY OUTTHEN RED FLAG CONDITIONS WILL LIKELY BE EXPANDED OVER THE AREA TUESDAY AND WEDNESDAY. FOR NOW...A FIRE WEATHER WATCH IS IN EFFECT TUESDAY FOR EL PASO COUNTY AND WILL LIKELY BE ISSUED FOR WEDNESDAY BY THE DAY SHIFT LATER TODAY. THERE IS A CHANCE AS THE TROUGH GETS CLOSER ON WED...THAT THE DRYLINE MAY BECOME ACTIVE OVER THE FAR E PLAINS. BOTH THE 00Z NAM AND EC HAVE A PRETTY POTENT DISTURBANCE MOVING ACROSS N CO AND THIS MAY ALLOW FOR ISOLD SVR TSRA OVER THE FAR E PLAINS. SPC HAS MENTIONED THIS IN THERE DAY3 OUTLOOK. LATEST 06Z NAM RUN HAS TROUGH EVEN SHARPER...AND THUS A BETTER CHANCE OF SOME STRONG THUNDER OVER THE FAR SE PLAINS OVERALL DRY WX EXPECTED THU AND FRI AS COOLER DRIER AIR MOVES IN BEHIND WED NIGHTS TROUGH PASSAGE. EC AND GFS HINT THAT THINGS SHOULD MOISTEN UP FOR THE WEEKEND...WITH EC MORE BULLISH ON PRECIP CHANCES. THIS INCREASING MOISTURE IS MAINLY BEING FORCED BY THE LOW LVLS (PATTERN ALOFT IS PRETTY FLAT)...AS CANADIAN HIGH PRESSURE BUILDS SOUTH AND SHUNTS HIGHER LLVL MOISTURE (50-60DWPT AIR) INTO THE REGION. FOR NOW...HAVE WIDESPREAD LOW END POPS OVER THE REGION...BUT THESE VALUES MAY NEED TO BE BUMPED UP...ESPECIALLY FOR SUNDAY...IF THE EC SOLUTION VERIFIES. /HODANISH && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 247 AM MDT MON JUN 16 2014 VFR CONDITIONS ARE EXPECTED TODAY THROUGH TONIGHT AT KCOS...KPUB AND KALS. STRONG SWRLY WINDS CAN BE EXPECTED THIS AFTERNOON AND EARLY THIS EVENING WITH GUSTS OF 30-35 KTS. && .PUB WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING FROM NOON TODAY TO 9 PM MDT THIS EVENING FOR COZ226-227. FIRE WEATHER WATCH FROM TUESDAY AFTERNOON THROUGH TUESDAY EVENING FOR COZ226-227. && $$ SHORT TERM...28 LONG TERM...HODANISH AVIATION...28
AREA FORECAST DISCUSSION
NWS ALBANY NY
401 PM EDT MON JUN 16 2014 .SYNOPSIS... A WEAK SURFACE FRONT WILL ALLOW FOR SOME SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS TONIGHT. BEHIND THIS FRONT...WARMER AND MORE HUMID AIR WILL IN PLACE FOR TUESDAY. SOME SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE TUESDAY NIGHT INTO WEDNESDAY...AS ANOTHER FRONTAL SYSTEM APPROACHES THE AREA...ALONG WITH CONTINUED WARM AND HUMID CONDITIONS. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... AS OF 401 PM EDT...A WEAK FRONTAL BOUNDARY IS APPROACHING THE REGION FROM THE WEST LATE THIS AFTERNOON. ACROSS OUR AREA...DEWPOINTS HAVE BEEN RATHER COMFORTABLE WITH READINGS IN THE 40S AND 50S. MEANWHILE...ON THE OTHER SIDE OF THE BOUNDARY...DEWPOINTS ACROSS WESTERN NY ARE IN THE MID 60S. THIS MORE HUMID AIR IS ON ITS WAY TOWARDS OUR REGION. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE ACCOMPANYING THIS WEAK BOUNDARY AS IT MOVES EASTWARD. MOST OF THE ACTIVITY SO FAR TODAY HAS REMAINED NORTH AND WEST OF OUR CWA. AS WE GO THROUGH THE EVENING HOURS...THE BOUNDARY WILL GET CLOSER TO OUR AREA AND THERE WILL BE THE CHANCE FOR SOME SCATTERED SHOWERS/ISOLD THUNDERSTORM ACTIVITY ACROSS OUR AREA. THE 16Z 3KM HRRR AND THE 12Z RUN OF OUR LOCAL HIRESWRF SHOW ACTIVITY APPROACHING OUR AREA FROM THE WEST THIS EVENING...BUT MAINLY WEAKENING WITH THE LOSS OF DAYTIME HEATING INTO TONIGHT. WE WILL GO WITH LOW POPS OVERNIGHT...WITH THE BEST CHANCE ACROSS NORTHERN AND WESTERN PARTS OF THE AREA. INSTABILITY IS LIMITED...SO MOST ACTIVITY WON/T HAVE THUNDER ASSOCIATED WITH IT. ALTHOUGH SKIES HAVE BEEN SUNNY FOR MOST OF THE DAY...THE APPROACHING BOUNDARY WILL INCREASE THE CLOUDS FOR THIS EVENING AND INTO THE OVERNIGHT. MOST AREAS WILL BE MOSTLY CLOUDY OVERNIGHT...AND THIS WILL PREVENT TEMPS FROM DROPPING AS MUCH AS THE PAST FEW NIGHTS. OVERNIGHT LOWS LOOKS TO MAINLY BE FROM THE UPPER 50S OVER THE HIGH TERRAIN TO THE MID 60S IN THE HUDSON VALLEY AND CAPITAL REGION. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/... THE FRONTAL BOUNDARY WILL BE MOVING AWAY FROM THE AREA BY SUNRISE TOMORROW MORNING...AND THE THREAT FOR SHOWERS WILL BE EAST OF OUR AREA. THE RESULT WILL BE CLEARING SKIES...WARM TEMPS...AND MUGGY CONDITIONS FOR TUESDAY. HIGH TEMPS LOOK TO REACH THE MID TO UPPER 80S FOR VALLEY AREAS WITH NO PRECIP EXPECTED. ANOTHER FRONTAL SYSTEM WILL BE APPROACHING WITHIN THE NW FLOW FOR TUESDAY NIGHT INTO WEDNESDAY. THE MODELS SHOW SOME TIMING DIFFERENCES REGARDING EXACTLY HOW AND WHEN THIS SYSTEM WILL AFFECT OUR AREA. SOME SHOWERS AND THUNDERSTORMS LOOK TO ACCOMPANY THE BOUNDARY. TODAY/S 12Z RUNS OF THE MODELS SUGGEST THAT THE FRONTAL BOUNDARY MAY BE MOVING THROUGH LATE TUESDAY NIGHT OR EARLY IN THE DAY WEDNESDAY...AS AN AREA OF LOW PRESSURE AND ASSOCIATED UPPER LEVEL DISTURBANCES PASSES TO OUR NORTH ACROSS SOUTHERN CANADA. WHILE EVERYWHERE STILL LOOKS TO HAVE THE OPPORTUNITY FOR SOME SHOWERS/THUNDERSTORMS...THE GREATEST THREAT FOR SEVERE WEATHER WILL BE FURTHER TO OUR SOUTH DURING THE PEAK HEATING ON WEDNESDAY. STILL...THE TIMING COULD CHANGE...AND PARTS OF OUR AREA COULD HAVE THE POTENTIAL FOR STRONG TO POSSIBLY SEVERE STORMS ON WED IF THE FRONT DOESN/T PROGRESS THROUGH AS FAST AS ANTICIPATED OR STALLS OVER OUR REGION. THE WARM AND HUMID CONDITIONS IN PLACE SHOULD ALLOW FOR PLENTY OF INSTABILITY...SO SEVERAL INGREDIENTS WOULD BE IN PLACE FOR STRONGER STORMS IF THE TIMING OF THE FRONT SLOWS DOWN. MIN TEMPS ON TUESDAY NIGHT LOOK MILD AND MUGGY WITH 60S EVERYWHERE. MAX TEMPS ON WEDNESDAY WILL BE WARM WITH MID 80S FOR MANY LOCATIONS. OVERNIGHT LOWS ON WED NIGHT WILL DEPEND ON JUST HOW QUICKLY THE FRONT MOVES THROUGH. WE HAVE GONE WITH A BLEND OF THE GUIDANCE FOR NOW...SUGGESTING 50S TO LOW 60S ACROSS THE AREA. && .LONG TERM /THURSDAY THROUGH MONDAY/... THE EXTENDED PERIOD STARTS OUT DRY...WITH INCREASING POPS TOWARD NEXT WEEK. A QUASI-STATIONARY FRONT...STRETCHING FROM LOW PRESSURE OVER MINNESOTA AND WISCONSIN TO THE DELMARVA PENINSULA...WILL MOVE VERY LITTLE THROUGH THE PERIOD. THE LOW ITSELF WILL BEGIN TO TRACK EAST EARLY NEXT WEEK...ACROSS THE LOWER GREAT LAKES...WITH THE FRONT OUT AHEAD OF IT STRUGGLING TO LIFT NORTH AS A WARM FRONT TOWARD OUR REGION. THE FIRST DECENT CHANCE FOR MEASURABLE SHOWERS WILL BE ON SUNDAY... BUT SHOWERS...ALONG WITH A GOOD LIKELIHOOD FOR THUNDERSTORMS...WILL BE THE MOST LIKELY ON MONDAY. MOSTLY CLEAR SKIES WILL FILL IN GRADUALLY...TOO...WITH MAINLY OVERCAST CONDITIONS BY LATE SUNDAY. BREAKS IN THE SUNSHINE ARE POSSIBLE BY MONDAY AFTERNOON IF THE WARM FRONT GETS CLOSE ENOUGH...RESULTING IN INCREASED INSTABILITY...AND THE CHANCE FOR THUNDERSTORMS...ESPECIALLY FROM ALBANY ON SOUTH AND WEST. THURSDAY WILL BE THE WARMEST DAY...WITH HIGH TEMPERATURES FROM AROUND 70 DEGREES IN THE HIGH PEAKS OF THE ADIRONDACKS AND GREENS... TO THE LOWER 80S DOWN THE HUDSON VALLEY WHICH WILL BE LARGELY INFLUENCED BY DOWNSLOPING NORTHWESTERLY WINDS. THEN FROM FRIDAY THROUGH MONDAY...IT WILL BE A FAIRLY STEADY PATTERN OF HIGHS FROM AROUND 70 DEGREES IN THE HIGH PEAKS OF THE ADIRONDACKS...CATSKILLS AND GREENS...TO THE UPPER 70S DOWN THE HUDSON VALLEY. THE MERCURY MAY BREAK 80 DEGREES IN A FEW SPOTS IN THE MID-HUDSON VALLEY ON FRIDAY. LOW TEMPERATURES THURSDAY AND FRIDAY NIGHTS WILL BE IN THE MID 40S TO MID 50S RANGE UNDER MOSTLY CLEAR TO PARTLY SUNNY SKIES. THE INCREASING CLOUDS WILL KEEP LOW READINGS UP IN THE MID 50S TO LOWER 60S RANGE BY SUNDAY NIGHT. NORMAL HIGHS IN ALBANY DURING THE PERIOD ARE AROUND 80 DEGREES...WITH UPPER 50S FOR LOWS. && .AVIATION /20Z MONDAY THROUGH SATURDAY/... HIGH PRESSURE WILL MOVE SOUTH OF THE REGION THIS AFTERNOON...AS A WEAK FRONTAL BOUNDARY MOVES ACROSS THE REGION TONIGHT. VFR CONDITIONS ARE EXPECTED FOR ALL THE TAF SITES PRIOR TO 17/04Z. CLOUDS WILL BE THICKENING AND LOWERING PRIOR TO SUNSET WITH A MID LEVEL CLOUD DECK IN THE 10-12 KFT AGL RANGE IMPACTING THE TERMINALS. ISOLD-SCT SHOWERS MAY MOVE IN SHORTLY BEFORE OR JUST AFTER MIDNIGHT. VCSH GROUPS HAVE BEEN USED FOR THIS SHOWER OR EVEN ISOLD -TSRA THREAT. THE SKIES MAY CLEAR A BIT TOWARDS 08Z SO THAT SOME MVFR MIST IS POSSIBLE AT ALL THE TAF SITES. THE WINDS WILL BE VARIABLE BUT MAINLY FROM THE SOUTH TO SOUTHWEST AT 5-8 KTS IN THE AFTERNOON. LIGHT WINDS ARE EXPECTED TONIGHT AT LESS THAN 5 KTS... EXCEPT AT KALB...WHERE SOME FUNNELING UP THE HUDSON RIVER VALLEY MAY KEEP THE SOUTHERLY WINDS GOING AT CLOSE TO 10 KTS. WINDS SHOULD BE WEST TO SOUTHWEST AT LESS THAN 10 KT TOMORROW MORNING. OUTLOOK... TUESDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA. WEDNESDAY: MODERATE OPERATIONAL IMPACT.BREEZY CHANCE OF SHRA...TSRA. WEDNESDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...TSRA. THURSDAY: NO OPERATIONAL IMPACT. NO SIG WX. THURSDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. FRIDAY: NO OPERATIONAL IMPACT. NO SIG WX. FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. SATURDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...TSRA. && .FIRE WEATHER... A FEW SHOWERS ARE POSSIBLE AROUND THE REGION TONIGHT WITH A PASSING FRONTAL BOUNDARY. RH VALUES WILL RECOVER TO 80 TO 95 PERCENT IN MOST LOCATIONS WITH A LIGHT TO CALM WIND. DRY WEATHER WILL RETURN TOMORROW WITH RH VALUES DROPPING TO 40 TO 50 PERCENT IN THE AFTERNOON WITH WEST WINDS AT 5 TO 10 MPH. THERE IS A CHANCE OF SHOWERS AND THUNDERSTORMS BETWEEN TUESDAY NIGHT AND WEDNESDAY WITH RH VALUES RETURNING TO 80 TO 100 PERCENT ON TUESDAY NIGHT...AND ONLY DROPPING TO 50 TO 65 PERCENT ON WEDNESDAY AFTERNOON. && .HYDROLOGY... THERE IS A SLIGHT TO LOW CHANCE FOR SOME SHOWERS AND THUNDERSTORMS THIS EVENING AS A WEAK SURFACE BOUNDARY MOVES ACROSS THE AREA. MOST OF THESE SHOWERS WILL BE FAIRLY LIGHT...AND RAIN SHOULD HAVE LITTLE EFFECT ON THE RIVERS AND STREAMS OF THE HSA. AFTER A DRY DAY ON TUESDAY...SOME MORE SHOWERS AND THUNDERSTORMS ARE POSSIBLE FOR TUESDAY NIGHT INTO WEDNESDAY. ALTHOUGH THERE ARE QUESTIONS STILL REMAINING ON JUST HOW ORGANIZED ANY SHOWER OR THUNDERSTORM ACTIVITY WILL BE...THERE WILL BE THE POTENTIAL FOR LOCALLY HEAVY RAINFALL WITHIN ANY THUNDERSTORM. ALTHOUGH THERE SHOULD BE NO WIDESPREAD HYDROLOGIC ISSUES...LOCALIZED ISSUES CANNOT BE RULED OUT AT THIS TIME. MAINLY DRY WEATHER LOOKS TO RETURN FOR THURSDAY THROUGH SATURDAY...AS COOLER AND LESS HUMID AIR MOVES INTO THE REGION. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...FRUGIS NEAR TERM...FRUGIS SHORT TERM...FRUGIS LONG TERM...ELH AVIATION...NAS FIRE WEATHER...FRUGIS HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS MIAMI FL
831 PM EDT TUE JUN 17 2014 .UPDATE... LATEST HIGH RESOLUTION MODELS ARE NOT INITIALIZING THE LARGE PRECIPITATION SHIELD ACROSS THE OFFSHORE ATLANTIC WATERS VERY WELL. LATEST RADAR TRENDS SHOW THIS SHIELD MOVING TO THE WEST- NORTHWEST VERY SLOWLY. MODERATE RAIN BANDS EMANATING OUT AHEAD ARE MOVING INTO EXTREME SOUTHERN MIAMI-DADE COUNTY. UPDATED POPS TO ACCOUNT FOR THE LATEST TRENDS. BELIEVE MOST OF THIS PRECIPITATION MAY LINGER THROUGH MUCH OF THE NIGHT BEING FED BY DEEP MOISTURE AND AN UPPER TROUGH DRAPED ACROSS THE AREA. && .PREV DISCUSSION... /ISSUED 754 PM EDT TUE JUN 17 2014/ AVIATION... LEFTOVER CONVECTION REMAINS ACROSS THE ATLANTIC WATERS EARLY THIS EVENING IN ASSOCIATION WITH AN UPPER LOW ACROSS THE AREA. THIS ACTIVITY IS SLOWLY PUSHING WEST-NORTHWEST BUT TENDS TO BE WEAKENING AS IT NEARS THE FLORIDA MAINLAND. HOWEVER...THERE IS STILL CONCERN THAT KMIA AND KTMB MAY BE AFFECTED OVER THE NEXT FEW HOURS. KEPT PRECIP MENTION OUT OF TAFS FOR NOW BUT WILL AMEND AS NECESSARY. PREV DISCUSSION... /ISSUED 221 PM EDT TUE JUN 17 2014/ DISCUSSION... INTERESTING WEATHER PATTERN TODAY. THE UPPER LEVEL TROUGH HAS BROUGHT THE INSTABILITY EXPECTED. HOWEVER, THUNDERSTORMS THIS MORNING CAUSED AN OUTFLOW BOUNDARY THAT MOVED ACROSS SOUTH FLORIDA. AS IT DID, IT CAUSED THE DEVELOPMENT OF SHOWERS AND THUNDERSTORMS IN THE WESTERN HALF OF THE CWA. THIS FORMED A DONUT HOLE SHAPE OF PRECIPITATION THAT HAS KEPT MOST OF THE SHOWERS OUT OF THE MIAMI DADE AREA. LOOKING AT CURRENT RADAR IMAGERY, THE CONVECTION OVER THE ATLANTIC IS BEGINNING TO DISSIPATE AND THE LINE OVER THE GULF SIDE IS BEGINNING TO BE ENHANCED. HOWEVER, GIVEN THE CLOUD COVER AND CONDITIONS, EXPECT THE SHOWERS AND GENERAL THUNDERSTORMS TO BE THE RULE TODAY, WITH ONLY SLIGHT CHANCES OF STRONG THUNDERSTORMS DEVELOPING, AND THOSE SHOULD BE ON THE GULF SIDE. THIS PATTERN IS SHOWN FAIRLY WELL BY THE HRRR 15Z RUN. SEE NO REASON TO DISAGREE WITH THE MODELS SOLUTION FOR THIS AFTERNOON. HAVE HIGHER POPS ALONG THE GULF COAST AND STILL MAINTAINING LOW END CHANCE POPS FOR THE ATLANTIC COAST, EXCEPT FOR PALM BEACH, WHERE HIGH END CHANCE AS SHOWERS ARE STILL IN THAT AREA. ACTIVE WEATHER WILL CONTINUE THROUGH THE REMAINDER OF THE WEEK AS AN UPPER LEVEL LOW HANGS AROUND OVER THE FLORIDA PENINSULA. A SURFACE HIGH, TO THE NORTHEAST, WILL SLOWLY STRENGTHEN THIS WEEK AND CAUSE THE SFC WINDS TO FLUCTUATE BETWEEN SOUTHERLY AND EASTERLY. THIS WILL KEEP MUCH OF THE CONVECTION IN THE INTERIOR AND GULF COAST THIS WEEK, WITH SOME NOCTURNAL AND EARLY TO MID MORNING ACTIVITY ALONG THE ATLANTIC COAST EACH DAY. LONG TERM... THE HIGH OVER NORTHERN FLORIDA WILL START TO MOVE SOUTHWARD THIS WEEKEND...AS A TROUGH OF LOW PRESSURE DEVELOPS OVER THE EASTERN UNTIED STATES. THIS WILL ALLOW FOR THE STEERING FLOW TO BECOME MORE SOUTHERLY OVER SOUTH FLORIDA THIS WEEKEND FOCUSING THE HIGHEST POPS OVER THE LAKE OKEECHOBEE REGION. THE HIGH WILL CONTINUE TO MOVE SOUTH INTO THE FLORIDA STRAITS EARLY NEXT WEEK...AS THE TROUGH OF LOW PRESSURE CONTINUES TO BUILD INTO THE EASTERN UNITED STATES. THIS WILL ALLOW FOR THE STEERING FLOW TO BECOME MORE SOUTHWEST OVER SOUTH FLORIDA EARLY NEXT WEEK FOCUSING THE HIGHEST POPS OVER THE EASTERN AREAS OF SOUTH FLORIDA. MARINE... AN UPPER LEVEL LOW WILL KEEP CONVECTIVE ACTIVITY OVER ALL SOUTH FLORIDA WATERS THROUGH THE WEEK. A SURFACE HIGH TO THE NORTHEAST WILL KEEP AN EAST TO SOUTH SOUTHEAST FLOW ACROSS THE WATER FOR THE TIME BEING. SEA SHOULD BE 1 TO 3 FEET THROUGH THE WEEK FOR THE ATLANTIC WATERS, WITH THE GULF SEEING SEA OF 1 TO 2 FEET. CONDITIONS UNDER CONVECTIVE SHOWERS OR THUNDERSTORMS COULD BECOME ROUGH AT TIMES. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 75 84 75 84 / 40 60 30 50 FORT LAUDERDALE 76 84 76 84 / 40 60 30 50 MIAMI 76 85 76 85 / 40 60 30 50 NAPLES 73 86 73 86 / 30 60 50 50 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$
AREA FORECAST DISCUSSION
NWS MIAMI FL
754 PM EDT TUE JUN 17 2014 .AVIATION... LEFTOVER CONVECTION REMAINS ACROSS THE ATLANTIC WATERS EARLY THIS EVENING IN ASSOCIATION WITH AN UPPER LOW ACROSS THE AREA. THIS ACTIVITY IS SLOWLY PUSHING WEST-NORTHWEST BUT TENDS TO BE WEAKENING AS IT NEARS THE FLORIDA MAINLAND. HOWEVER...THERE IS STILL CONCERN THAT KMIA AND KTMB MAY BE AFFECTED OVER THE NEXT FEW HOURS. KEPT PRECIP MENTION OUT OF TAFS FOR NOW BUT WILL AMEND AS NECESSARY. && .PREV DISCUSSION... /ISSUED 221 PM EDT TUE JUN 17 2014/ DISCUSSION... INTERESTING WEATHER PATTERN TODAY. THE UPPER LEVEL TROUGH HAS BROUGHT THE INSTABILITY EXPECTED. HOWEVER, THUNDERSTORMS THIS MORNING CAUSED AN OUTFLOW BOUNDARY THAT MOVED ACROSS SOUTH FLORIDA. AS IT DID, IT CAUSED THE DEVELOPMENT OF SHOWERS AND THUNDERSTORMS IN THE WESTERN HALF OF THE CWA. THIS FORMED A DONUT HOLE SHAPE OF PRECIPITATION THAT HAS KEPT MOST OF THE SHOWERS OUT OF THE MIAMI DADE AREA. LOOKING AT CURRENT RADAR IMAGERY, THE CONVECTION OVER THE ATLANTIC IS BEGINNING TO DISSIPATE AND THE LINE OVER THE GULF SIDE IS BEGINNING TO BE ENHANCED. HOWEVER, GIVEN THE CLOUD COVER AND CONDITIONS, EXPECT THE SHOWERS AND GENERAL THUNDERSTORMS TO BE THE RULE TODAY, WITH ONLY SLIGHT CHANCES OF STRONG THUNDERSTORMS DEVELOPING, AND THOSE SHOULD BE ON THE GULF SIDE. THIS PATTERN IS SHOWN FAIRLY WELL BY THE HRRR 15Z RUN. SEE NO REASON TO DISAGREE WITH THE MODELS SOLUTION FOR THIS AFTERNOON. HAVE HIGHER POPS ALONG THE GULF COAST AND STILL MAINTAINING LOW END CHANCE POPS FOR THE ATLANTIC COAST, EXCEPT FOR PALM BEACH, WHERE HIGH END CHANCE AS SHOWERS ARE STILL IN THAT AREA. ACTIVE WEATHER WILL CONTINUE THROUGH THE REMAINDER OF THE WEEK AS AN UPPER LEVEL LOW HANGS AROUND OVER THE FLORIDA PENINSULA. A SURFACE HIGH, TO THE NORTHEAST, WILL SLOWLY STRENGTHEN THIS WEEK AND CAUSE THE SFC WINDS TO FLUCTUATE BETWEEN SOUTHERLY AND EASTERLY. THIS WILL KEEP MUCH OF THE CONVECTION IN THE INTERIOR AND GULF COAST THIS WEEK, WITH SOME NOCTURNAL AND EARLY TO MID MORNING ACTIVITY ALONG THE ATLANTIC COAST EACH DAY. LONG TERM... THE HIGH OVER NORTHERN FLORIDA WILL START TO MOVE SOUTHWARD THIS WEEKEND...AS A TROUGH OF LOW PRESSURE DEVELOPS OVER THE EASTERN UNTIED STATES. THIS WILL ALLOW FOR THE STEERING FLOW TO BECOME MORE SOUTHERLY OVER SOUTH FLORIDA THIS WEEKEND FOCUSING THE HIGHEST POPS OVER THE LAKE OKEECHOBEE REGION. THE HIGH WILL CONTINUE TO MOVE SOUTH INTO THE FLORIDA STRAITS EARLY NEXT WEEK...AS THE TROUGH OF LOW PRESSURE CONTINUES TO BUILD INTO THE EASTERN UNITED STATES. THIS WILL ALLOW FOR THE STEERING FLOW TO BECOME MORE SOUTHWEST OVER SOUTH FLORIDA EARLY NEXT WEEK FOCUSING THE HIGHEST POPS OVER THE EASTERN AREAS OF SOUTH FLORIDA. MARINE... AN UPPER LEVEL LOW WILL KEEP CONVECTIVE ACTIVITY OVER ALL SOUTH FLORIDA WATERS THROUGH THE WEEK. A SURFACE HIGH TO THE NORTHEAST WILL KEEP AN EAST TO SOUTH SOUTHEAST FLOW ACROSS THE WATER FOR THE TIME BEING. SEA SHOULD BE 1 TO 3 FEET THROUGH THE WEEK FOR THE ATLANTIC WATERS, WITH THE GULF SEEING SEA OF 1 TO 2 FEET. CONDITIONS UNDER CONVECTIVE SHOWERS OR THUNDERSTORMS COULD BECOME ROUGH AT TIMES. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 75 84 75 84 / 40 60 30 50 FORT LAUDERDALE 76 84 76 84 / 40 60 30 50 MIAMI 76 85 76 85 / 40 60 30 50 NAPLES 73 86 73 86 / 30 60 50 50 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
937 AM EDT MON JUN 16 2014 .UPDATE... AS HIGH PRESSURE RIDGE BUILDS NORTHEAST OF THE REGION TODAY...THE FLOW WILL BECOME ONSHORE. THIS WILL HELP PUSH SEA BREEZE INLAND FASTER AND FARTHER TODAY. THE LATEST HRRR INDICATES THE MAJORITY OF CONVECTION OCCURING WELL INLAND THIS AFTERNOON...FOCUSED NEAR THE I75 CORRIDOR. THE MORNING JAX SOUNDING INDICATES A CONVECTIVE TEMP OF 89 TODAY...WITH CAPPING AROUND 600MB. GIVEN THESE OBSERVATIONS...THE HRRR DEPICTION LOOKS REASONABLE. && .PRELIMINARY POINT TEMPS/POPS... AMG 92 68 93 69 / 30 10 20 20 SSI 84 74 85 74 / 10 10 10 10 JAX 89 69 89 71 / 20 10 20 10 SGJ 86 73 86 73 / 20 10 10 10 GNV 91 68 91 68 / 50 30 20 20 OCF 90 68 91 70 / 40 30 30 30 && .JAX WATCHES/WARNINGS/ADVISORIES... FL...NONE. GA...NONE. AM...NONE. && $$ STRUBLE
AREA FORECAST DISCUSSION...UPDATE FOR AVIATION
NWS PEACHTREE CITY GA
147 PM EDT MON JUN 16 2014 .MORNING UPDATE... /ISSUED AT 1050 AM EDT MON JUN 16 2014/ NO MAJOR CHANGES PLANNED FOR THIS MORNING AS CURRENT FORECAST LOOKS ON TRACK. MORNING SOUNDING SURFACE ANALYSIS SUPPORT ANOTHER ROUND OF SCATTERED AFTERNOON/EVENING THUNDERSTORMS... BUT HIGH PRESSURE INFLUENCE SHOULD HELP HOLD STORMS BELOW SEVERE LIMITS. A WEAK SUBTLE SURFACE TROUGH OVER THE EASTERN HALF OF THE FORECAST AREA SUGGEST AREAS GENERALLY EAST OF A DALTON TO PEACHTREE CITY TO AMERICUS LINE MAY HAVE SLIGHTLY GREATER CHANCES... ALTHOUGH AN ISOLATED STORM COULD OCCUR JUST ABOUT ANYWHERE TODAY. CONVECTIVE TEMP IS IN THE LOWER 90S... SO SHOULD SEE SCATTERED CONVECTION DEVELOP BY 3-4 PM THIS AFTERNOON. /39 .PREV DISCUSSION... /ISSUED 335 AM EDT MON JUN 16 2014/ SHORT TERM /TODAY THROUGH TUESDAY/... 500MB ANALYSIS SHOWS HIGH PRESSURE ACROSS THE SE STATES. AT THE SURFACE...A WEAK BOUNDARY PERSISTS ACROSS CENTRAL GA. HIGH PRESSURE WILL CONTINUE TO BUILD ACROSS THE SE THROUGH TUESDAY. THE WEAK SURFACE BOUNDARY SHOULD DISSIPATE LATER TODAY...BUT A LEE TROUGH WILL BEGIN TO SET UP ON TUESDAY. IR IMAGERY SHOWS SOME CLOUD DEBRIS STILL AROUND FROM THE EVENING SHOWERS AND THUNDERSTORMS. THE CLOUDS SHOULD DECREASE BY SUNRISE. DIURNAL CU SHOULD DEVELOP BY MID TO LATE MORNING. SCATTERED SHOWERS AND THUNDERSTORMS WILL ONCE AGAIN DEVELOP THIS AFTERNOON AND LINGER INTO THE EVENING HOURS. THE LATEST RUN OF THE HRRR IS NOT REALLY PINGING ONE SPECIFIC PLACE FOR INITIATION. HOWEVER...THE DISSIPATING BOUNDARY MAY FOCUS SOME ACTIVITY WITH OUTFLOWS CONTINUING TO FOCUS ANY STORMS. CONVECTIVE COVERAGE SHOULD BE SLIGHTLY LESS ON TUESDAY WITH HIGH PRESSURE GETTING STRONGER ALOFT. SEVERE WEATHER IS NOT ANTICIPATED TODAY OR TUESDAY. HOWEVER...THUNDERSTORMS WILL HAVE THE POTENTIAL TO PRODUCE LOCALLY HEAVY DOWNPOURS AND GUSTY WINDS. NLISTEMAA LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... EXTENDED IS FOLLOWING THE SAME TRENDS AS IT HAS BEEN THE PAST FEW DAYS...WITH UPPER RIDGING DOMINATING THE AREA AND THE TAIL END OF A WEAK FRONT MOVING INTO NORTH GEORGIA BY MIDWEEK. THIS ALONG WITH OROGRAPHIC LIFT WILL HELP TO ENHANCE AFTERNOON CONVECTION. EXPECT AN INCREASING TREND IN TEMPERATURES WITH HIGHS INTO THE MID 90S IN SOME AREAS ESPECIALLY CENTRAL AND SOUTH BY THE END OF THE WORK WEEK. CURRENT GUIDANCE IS WANTING TO BACK OFF JUST A TAD ON TEMPS TOWARD THE END OF THE EXTENDED AS THE UPPER RIDGE BEGINS TO BREAK DOWN AND ADDITIONAL MOISTURE OVERSPREADS THE AREA. TDP && .AVIATION... 18Z UPDATE... A DIRTY MID-UPPER RIDGE AND WEAK SURFACE TROUGH ACROSS THE AREA WILL RESULT IN SCATTERED AFTERNOON/EVENING SHOWERS AND THUNDERSTORMS THIS AFTERNOON AND AGAIN ON TUESDAY... WITH THE MORE FAVORABLE TIME BETWEEN 20-24Z AT ATL. EXPECT SUFFICIENT LOW LEVEL MOISTURE TO PRODUCE BKN050 BY 18Z EACH AFTERNOON. CONVECTION SHOULD GREATLY DIMINISH BY 02Z WITH FEW100 TO SKC EXPECTED OVERNIGHT. PATCHY MVFR FOG IS POSSIBLE AGAIN TONIGHT FOR AREAS THAT SEE SOME RAIN. WINDS TRICKY... BUT SHOULD SEE L&V OVERNIGHT... MAINLY SSW AT 7KTS OR LESS ON TUE. //ATL CONFIDENCE...18Z UPDATE... MEDIUM CONFIDENCE ON WINDS AND TSRA EFFECTING ANY AIRPORT. HIGH CONFIDENCE ON REMAINING ELEMENTS. && && .PRELIMINARY POINT TEMPS/POPS... ATHENS 93 71 92 71 / 40 40 30 20 ATLANTA 91 73 92 74 / 30 30 20 20 BLAIRSVILLE 87 65 86 66 / 40 40 30 20 CARTERSVILLE 92 71 93 70 / 20 20 30 20 COLUMBUS 94 73 94 74 / 30 30 20 10 GAINESVILLE 91 70 91 72 / 40 40 30 20 MACON 93 71 94 70 / 30 30 20 10 ROME 92 69 93 70 / 20 20 30 10 PEACHTREE CITY 92 70 92 70 / 40 40 20 20 VIDALIA 92 70 93 73 / 30 30 20 10 && .FFC WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION...UPDATE
NWS PEACHTREE CITY GA
1050 AM EDT MON JUN 16 2014 .MORNING UPDATE... NO MAJOR CHANGES PLANNED FOR THIS MORNING AS CURRENT FORECAST LOOKS ON TRACK. MORNING SOUNDING SURFACE ANALYSIS SUPPORT ANOTHER ROUND OF SCATTERED AFTERNOON/EVENING THUNDERSTORMS... BUT HIGH PRESSURE INFLUENCE SHOULD HELP HOLD STORMS BELOW SEVERE LIMITS. A WEAK SUBTLE SURFACE TROUGH OVER THE EASTERN HALF OF THE FORECAST AREA SUGGEST AREAS GENERALLY EAST OF A DALTON TO PEACHTREE CITY TO AMERICUS LINE MAY HAVE SLIGHTLY GREATER CHANCES... ALTHOUGH AN ISOLATED STORM COULD OCCUR JUST ABOUT ANYWHERE TODAY. CONVECTIVE TEMP IS IN THE LOWER 90S... SO SHOULD SEE SCATTERED CONVECTION DEVELOP BY 3-4 PM THIS AFTERNOON. /39 .PREV DISCUSSION... /ISSUED 335 AM EDT MON JUN 16 2014/ SHORT TERM /TODAY THROUGH TUESDAY/... 500MB ANALYSIS SHOWS HIGH PRESSURE ACROSS THE SE STATES. AT THE SURFACE...A WEAK BOUNDARY PERSISTS ACROSS CENTRAL GA. HIGH PRESSURE WILL CONTINUE TO BUILD ACROSS THE SE THROUGH TUESDAY. THE WEAK SURFACE BOUNDARY SHOULD DISSIPATE LATER TODAY...BUT A LEE TROUGH WILL BEGIN TO SET UP ON TUESDAY. IR IMAGERY SHOWS SOME CLOUD DEBRIS STILL AROUND FROM THE EVENING SHOWERS AND THUNDERSTORMS. THE CLOUDS SHOULD DECREASE BY SUNRISE. DIURNAL CU SHOULD DEVELOP BY MID TO LATE MORNING. SCATTERED SHOWERS AND THUNDERSTORMS WILL ONCE AGAIN DEVELOP THIS AFTERNOON AND LINGER INTO THE EVENING HOURS. THE LATEST RUN OF THE HRRR IS NOT REALLY PINGING ONE SPECIFIC PLACE FOR INITIATION. HOWEVER...THE DISSIPATING BOUNDARY MAY FOCUS SOME ACTIVITY WITH OUTFLOWS CONTINUING TO FOCUS ANY STORMS. CONVECTIVE COVERAGE SHOULD BE SLIGHTLY LESS ON TUESDAY WITH HIGH PRESSURE GETTING STRONGER ALOFT. SEVERE WEATHER IS NOT ANTICIPATED TODAY OR TUESDAY. HOWEVER...THUNDERSTORMS WILL HAVE THE POTENTIAL TO PRODUCE LOCALLY HEAVY DOWNPOURS AND GUSTY WINDS. NLISTEMAA LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... EXTENDED IS FOLLOWING THE SAME TRENDS AS IT HAS BEEN THE PAST FEW DAYS...WITH UPPER RIDGING DOMINATING THE AREA AND THE TAIL END OF A WEAK FRONT MOVING INTO NORTH GEORGIA BY MIDWEEK. THIS ALONG WITH OROGRAPHIC LIFT WILL HELP TO ENHANCE AFTERNOON CONVECTION. EXPECT AN INCREASING TREND IN TEMPERATURES WITH HIGHS INTO THE MID 90S IN SOME AREAS ESPECIALLY CENTRAL AND SOUTH BY THE END OF THE WORK WEEK. CURRENT GUIDANCE IS WANTING TO BACK OFF JUST A TAD ON TEMPS TOWARD THE END OF THE EXTENDED AS THE UPPER RIDGE BEGINS TO BREAK DOWN AND ADDITIONAL MOISTURE OVERSPREADS THE AREA. TDP AVIATION... /ISSUED AT 724 AM EDT MON JUN 16 2014/ 12Z UPDATE... SCATTERED AFTERNOON SHOWERS AND THUNDERSTORMS ARE EXPECTED THIS AFTERNOON WITH ANY CIGS AROUND 5KFT. CONVECTION SHOULD DIMINISH WITH THE LOSS OF HEATING. CLEARING SKIES ARE EXPECTED AFTER SUNSET. LESS CONVECTION TUESDAY AS HIGH PRESSURE ALOFT BUILDS. PATCHY MVFR FOG IS POSSIBLE AGAIN TONIGHT WHERE IT RAINS. //ATL CONFIDENCE...12Z UPDATE... MEDIUM CONFIDENCE ON WINDS. HIGH CONFIDENCE REMAINING ELEMENTS. && && .PRELIMINARY POINT TEMPS/POPS... ATHENS 93 71 92 71 / 40 40 30 20 ATLANTA 91 73 92 74 / 30 30 20 20 BLAIRSVILLE 87 65 86 66 / 40 40 30 20 CARTERSVILLE 92 71 93 70 / 20 20 30 20 COLUMBUS 94 73 94 74 / 30 30 20 10 GAINESVILLE 91 70 91 72 / 40 40 30 20 MACON 93 71 94 70 / 30 30 20 10 ROME 92 69 93 70 / 20 20 30 10 PEACHTREE CITY 92 70 92 70 / 40 40 20 20 VIDALIA 92 70 93 73 / 30 30 20 10 && .FFC WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
724 AM EDT MON JUN 16 2014 .PREV DISCUSSION... /ISSUED 335 AM EDT MON JUN 16 2014/ SHORT TERM /TODAY THROUGH TUESDAY/... 500MB ANALYSIS SHOWS HIGH PRESSURE ACROSS THE SE STATES. AT THE SURFACE...A WEAK BOUNDARY PERSISTS ACROSS CENTRAL GA. HIGH PRESSURE WILL CONTINUE TO BUILD ACROSS THE SE THROUGH TUESDAY. THE WEAK SURFACE BOUNDARY SHOULD DISSIPATE LATER TODAY...BUT A LEE TROUGH WILL BEGIN TO SET UP ON TUESDAY. IR IMAGERY SHOWS SOME CLOUD DEBRIS STILL AROUND FROM THE EVENING SHOWERS AND THUNDERSTORMS. THE CLOUDS SHOULD DECREASE BY SUNRISE. DIURNAL CU SHOULD DEVELOP BY MID TO LATE MORNING. SCATTERED SHOWERS AND THUNDERSTORMS WILL ONCE AGAIN DEVELOP THIS AFTERNOON AND LINGER INTO THE EVENING HOURS. THE LATEST RUN OF THE HRRR IS NOT REALLY PINGING ONE SPECIFIC PLACE FOR INITIATION. HOWEVER...THE DISSIPATING BOUNDARY MAY FOCUS SOME ACTIVITY WITH OUTFLOWS CONTINUING TO FOCUS ANY STORMS. CONVECTIVE COVERAGE SHOULD BE SLIGHTLY LESS ON TUESDAY WITH HIGH PRESSURE GETTING STRONGER ALOFT. SEVERE WEATHER IS NOT ANTICIPATED TODAY OR TUESDAY. HOWEVER...THUNDERSTORMS WILL HAVE THE POTENTIAL TO PRODUCE LOCALLY HEAVY DOWNPOURS AND GUSTY WINDS. NLISTEMAA LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... EXTENDED IS FOLLOWING THE SAME TRENDS AS IT HAS BEEN THE PAST FEW DAYS...WITH UPPER RIDGING DOMINATING THE AREA AND THE TAIL END OF A WEAK FRONT MOVING INTO NORTH GEORGIA BY MIDWEEK. THIS ALONG WITH OROGRAPHIC LIFT WILL HELP TO ENHANCE AFTERNOON CONVECTION. EXPECT AN INCREASING TREND IN TEMPERATURES WITH HIGHS INTO THE MID 90S IN SOME AREAS ESPECIALLY CENTRAL AND SOUTH BY THE END OF THE WORK WEEK. CURRENT GUIDANCE IS WANTING TO BACK OFF JUST A TAD ON TEMPS TOWARD THE END OF THE EXTENDED AS THE UPPER RIDGE BEGINS TO BREAK DOWN AND ADDITIONAL MOISTURE OVERSPREADS THE AREA. TDP AVIATION... 12Z UPDATE... SCATTERED AFTERNOON SHOWERS AND THUNDERSTORMS ARE EXPECTED THIS AFTERNOON WITH ANY CIGS AROUND 5KFT. CONVECTION SHOULD DIMINISH WITH THE LOSS OF HEATING. CLEARINGSKIES ARE EXPECTED AFTER SUNSET. LESS CONVECTIION TUESDAY AS HIGH PRESSURE ALOFT BUILDS. PATCHY MVFR FOG IS POSSIBLE AGAIN TONIGHT WHERE IT RAINS. //ATL CONFIDENCE...12Z UPDATE... MEDIUM CONFIDENCE ON WINDS. HIGH CONFIDENCE REMAINING ELEMENTS. && && .PRELIMINARY POINT TEMPS/POPS... ATHENS 93 71 92 71 / 40 40 30 20 ATLANTA 91 73 92 74 / 30 30 20 20 BLAIRSVILLE 87 65 86 66 / 40 40 30 20 CARTERSVILLE 92 71 93 70 / 20 20 30 20 COLUMBUS 94 73 94 74 / 30 30 20 10 GAINESVILLE 91 70 91 72 / 40 40 30 20 MACON 93 71 94 70 / 30 30 20 10 ROME 92 69 93 70 / 20 20 30 10 PEACHTREE CITY 92 70 92 70 / 40 40 20 20 VIDALIA 92 70 93 73 / 30 30 20 10 && .FFC WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
335 AM EDT MON JUN 16 2014 .SHORT TERM /TODAY THROUGH TUESDAY/... 500MB ANALYSIS SHOWS HIGH PRESSURE ACROSS THE SE STATES. AT THE SURFACE...A WEAK BOUNDARY PERSISTS ACROSS CENTRAL GA. HIGH PRESSURE WILL CONTINUE TO BUILD ACROSS THE SE THROUGH TUESDAY. THE WEAK SURFACE BOUNDARY SHOULD DISSIPATE LATER TODAY...BUT A LEE TROUGH WILL BEGIN TO SET UP ON TUESDAY. IR IMAGERY SHOWS SOME CLOUD DEBRIS STILL AROUND FROM THE EVENING SHOWERS AND THUNDERSTORMS. THE CLOUDS SHOULD DECREASE BY SUNRISE. DIURNAL CU SHOULD DEVELOP BY MID TO LATE MORNING. SCATTERED SHOWERS AND THUNDERSTORMS WILL ONCE AGAIN DEVELOP THIS AFTERNOON AND LINGER INTO THE EVENING HOURS. THE LATEST RUN OF THE HRRR IS NOT REALLY PINGING ONE SPECIFIC PLACE FOR INITIATION. HOWEVER...THE DISSIPATING BOUNDARY MAY FOCUS SOME ACTIVITY WITH OUTFLOWS CONTINUING TO FOCUS ANY STORMS. CONVECTIVE COVERAGE SHOULD BE SLIGHTLY LESS ON TUESDAY WITH HIGH PRESSURE GETTING STRONGER ALOFT. SEVERE WEATHER IS NOT ANTICIPATED TODAY OR TUESDAY. HOWEVER...THUNDERSTORMS WILL HAVE THE POTENTIAL TO PRODUCE LOCALLY HEAVY DOWNPOURS AND GUSTY WINDS. NLISTEMAA .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... EXTENDED IS FOLLOWING THE SAME TRENDS AS IT HAS BEEN THE PAST FEW DAYS...WITH UPPER RIDGING DOMINATING THE AREA AND THE TAIL END OF A WEAK FRONT MOVING INTO NORTH GEORGIA BY MIDWEEK. THIS ALONG WITH OROGRAPHIC LIFT WILL HELP TO ENHANCE AFTERNOON CONVECTION. EXPECT AN INCREASING TREND IN TEMPERATURES WITH HIGHS INTO THE MID 90S IN SOME AREAS ESPECIALLY CENTRAL AND SOUTH BY THE END OF THE WORK WEEK. CURRENT GUIDANCE IS WANTING TO BACK OFF JUST A TAD ON TEMPS TOWARD THE END OF THE EXTENDED AS THE UPPER RIDGE BEGINS TO BREAK DOWN AND ADDITIONAL MOISTURE OVERSPREADS THE AREA. TDP && .AVIATION... 06Z UPDATE... PATCHY MVFR FOG IS POSSIBLE THIS MORNING AROUND THE TERMINAL SITES...ESPECIALLY THOSE LOCALES THAT RECEIVED RAINFALL. SCATTERED AFTERNOON CONVECTION EXPECTED TODAY WITH ANY CIGS AROUND 5KFT. CLEARING EXPECTED AFTER SUNSET. LESS CONVECTIVE TUESDAY AS HIGH PRESSURE ALOFT BUILDS. //ATL CONFIDENCE...06Z UPDATE... MEDIUM CONFIDENCE ON WINDS. HIGH CONFIDENCE REMAINING ELEMENTS. && .PRELIMINARY POINT TEMPS/POPS... ATHENS 93 71 92 71 / 40 40 30 20 ATLANTA 91 73 92 74 / 30 30 20 20 BLAIRSVILLE 87 65 86 66 / 40 40 30 20 CARTERSVILLE 92 71 93 70 / 20 20 30 20 COLUMBUS 94 73 94 74 / 30 30 20 10 GAINESVILLE 91 70 91 72 / 40 40 30 20 MACON 93 71 94 70 / 30 30 20 10 ROME 92 69 93 70 / 20 20 30 10 PEACHTREE CITY 92 70 92 70 / 40 40 20 20 VIDALIA 92 70 93 73 / 30 30 20 10 && .FFC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...NLISTEMAA LONG TERM....TDP AVIATION...NLISTEMAA
AREA FORECAST DISCUSSION
NWS POCATELLO ID
314 AM MDT MON JUN 16 2014 .SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT. SAT IMAGERY SHOWS UPPER TROUGH EXTENDED THROUGH THE PACNW. MAIN CIRCULATION CENTER CURRENTLY OVER SEATTLE/VANCOUVER BC. ONE SHORTWAVE PUSHING THROUGH SOUTHEAST IDAHO WITH ANOTHER DIGGING INTO NORTHERN CALIFORNIA AND NORTHWEST NEVADA. RADAR SHOWS POCKETS OF WEAK PRECIP ECHOES OVER SOUTHERN IDAHO THOUGH STRONGER CONVECTION WITH A FEW LIGHTNING STRIKES IN WESTERN IDAHO THIS MORNING. HRRR AND NAM BRING CONSOLIDATED BAND OF PRECIP INTO THE REGION DURING THE MORNING AS MAIN FEATURE CLOSES OFF AND DIGS INTO NORTHEAST OREGON THROUGH THE DAY TODAY. UPPER JET DIGGING INTO BASE OF TROUGH LATE TODAY BEGINS TO EJECT NORTH ACROSS SOUTHEAST IDAHO THIS EVENING. INSTABILITY NOT IMPRESSIVE SO LIMITED TSTORM THREAT TO ISOLATED COVERAGE. UPPER LOW CONTINUES TO ROTATE INTO THE REGION WITH CONTINUED COOL AND CONVECTIVE CONDITIONS. GFS AND NAM VERY CLOSE IN SOLUTIONS WITH ONLY MINOR DEVIATIONS IN PLACEMENT OF QPF BANDS. THUS HAVE GOOD CONFIDENCE IN MAINTAINING HIGH POPS MOVING THROUGH TUESDAY. CENTER OF UPPER LOW SHIFTS NORTHEAST INTO MONTANA TUESDAY NIGHT LEAVING ELONGATED TROUGH THROUGH EAST IDAHO INTO UTAH. DRY SLOT PUNCHES THROUGH SNAKE PLAIN AND SOUTHERN HIGHLANDS TUESDAY NIGHT INTO WEDNESDAY AGAIN WITH GOOD AGREEMENT BETWEEN NAM/GFS. WRAP AROUND MOISTURE DIGS INTO NORTHERN PORTIONS OF FORECAST AREA FOR HIGHEST POPS ACROSS CENTRAL MOUNTAINS AND ALONG DIVIDE LATE TUESDAY NIGHT INTO WEDNESDAY. BY WEDNESDAY NIGHT...TROUGH AXIS HAS SHIFTED WELL INTO WYOMING WITH WRAP AROUND MOISTURE IMPACTING EXTREME NORTHEAST CORNER AND RIDGE BEGINNING TO AMPLIFY INTO THE PACNW. DMH .LONG TERM...THURSDAY THROUGH MONDAY. UPPER RIDGE BUILDS EARLY IN THE EXTENDED FOR RAPIDLY WARMING TEMPS THURSDAY INTO FRIDAY. EAST IDAHO BETWEEN CLOSED LOW OVER UPPER PLAINS AND NEXT AMPLIFIED TROUGH OFF PACIFIC COAST. BOTH GFS/ECMWF SHIFT TO SOUTHWEST FLOW BY LATE SATURDAY THOUGH QUITE A BIT DIFFERENCE IN DETAILS. BOTH MODELS FAVOR AN UPTICK IN CONVECTIVE ACTIVITY THROUGH THE WEEKEND WITH ECMWF THE WETTER MODEL. THERE ARE DIFFERENCES IN HOW THE MODELS HANDING THE UPPER PLAINS LOW THROUGH THE WEEKEND...SO HANDLING OF UPSTREAM RIDGE OVER THE INTERMOUNTAIN WEST AND RESULTING CONVECTIVE SCENARIOS ARE SLIGHTLY DIFFERENT. OPTED TO KEEP POPS NEAR TO ABOVE CLIMO THROUGH REMAINDER OF EXTENDED WITH TEMPS CLOSE TO GUIDANCE BLEND. DMH && .AVIATION...CLOUDS AND ASSOCIATED MOISTURE ON THE INCREASE THIS MORNING. RADAR RETURNS BEGINNING TO SHOW AND EXPECT THE TREND TO CONTINUE AS THE DAY PROGRESSES. UPPER LOW ADVANCING INTO THE AREA TO BRING A GOOD SHOT OF PRECIPITATION TO ALL TAF SITES BY THIS AFTERNOON. CIGS TO LOWER AFTER 18Z WITH ISOLD TSTORMS EXPECTED THRU THE AFTERNOON AND EVENING. SHRA EXPECTED THROUGH 12Z TUESDAY. DITTMANN && .FIRE WEATHER...A GOOD SHOT OF PRECIPITATION EXPECTED THIS AFTERNOON. INITIAL SHOT ACCOMPANIED BY LIGHTNING BUT WE DO EXPECT WETTING RAINS FOR MOST AREAS. RAIN BECOMES THE DOMINANT FEATURE TONIGHT ALONG WITH COOLER TEMPS AND OF COURSE HIGHER HUMIDITIES. THIS IS WHAT THE DOCTOR ORDERED TO HELP FINER FUELS MOISTEN UP. ONCE THE MAIN UPPER LOW PASSES MID WEEK...WE WILL SEE A RETURN TO DRIER AND WARMER WEATHER. DITTMANN && .PIH WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1258 PM CDT MON JUN 16 2014 .DISCUSSION... 1123 AM CDT NO MAJOR CHANGES MADE TO THIS AFTERNOONS FORECAST. VISIBLE SATELLITE AND SURFACE OBSERVATIONS INDICATE THE INFLUX OF RICH LOW-LEVEL MOISTURE IS ADVANCING NORTHWARD ACROSS NORTHERN MO/CENTRAL IL. CUMULUS HAS DEVELOPED ACROSS THE SOUTHERN CWA AND RAP SOUNDINGS INDICATE LITTLE IN THE WAY OF CINH TO THE LFC...WHERE AROUND 1500-2000 J/KG OF SBCAPE IS PRESENT ABOVE. WHILE NOTHING OF PARTICULAR NOTE IS SEEN ON WATER VAPOR SATELLITE UPSTREAM INTO MO...IT MAY NOT TAKE TOO MUCH TO TRIGGER ISOLATED STORMS BY MID-AFTERNOON IN JUST THE GENERAL LOW-LEVEL WAA FLOW ACROSS THE REGION. WITH THE HIGH AMOUNT OF CAPE...THERE IS A CONDITIONAL RISK OF A STRONG TO SEVERE STORM OR TWO. THE FORECAST FOR TONIGHT REMAINS TRICKY. CONVECTION NEAR THE NE/IA BORDER IS PRIMARILY ELEVATED AND NOT REALLY CONGEALING OR BECOMING ROOTED LOWER AT THIS TIME...ALTHOUGH MAY BECOME A LITTLE MORE FAVORABLE IN TIME /SEE SPC MCD/. UPSCALE GROWTH IS EXPECTED INTO SOUTHERN MN WITH EVENTUAL CONGEALING INTO AN MCS THIS EVE INTO OVERNIGHT...WHICH A HIGH AMOUNT OF CONVECTIVE-ALLOWING GUIDANCE SHOWS. WHILE MUCH OF THE GUIDANCE DOES BRING THE BRUNT OF THAT NORTH OF THE AREA...THE PATTERN...SLOPE OF THE INSTABILITY GRADIENT...AND OBSERVATIONAL TRENDS WOULD INDICATE THAT MAYBE THE SUITE OF GUIDANCE IS TOO FAR NORTH...AND AT LEAST THE SOUTHERN PORTION OF THE COMPLEX...OR WHAT BACKBUILDS AGAINST THE LOW- LEVEL JET NOSE WOULD EVOLVE INTO FAR NORTHERN IL LATE TONIGHT. THIS WOULD GREATLY INFLUENCE TEMPERATURES AND HEAT INDICES...AS WELL AS CONVECTIVE REDEVELOPMENT POTENTIAL...ON TUESDAY. NEEDLESS TO SAY FORECAST CONFIDENCE ON TUESDAY WILL REMAIN MAINLY LOW. IF NO TO LITTLE INFLUENCE OF CLOUDS/STORMS LATE TONIGHT AND EARLY TUESDAY...HEAT INDEX READINGS OF 95 TO 100 COULD ENCOMPASS MUCH OF THE FORECAST AREA...INCLUDING CHICAGO. WHILE NOT ADVISORY CRITERIA...THE FIRST READINGS THAT WARM IN A SEASON CAN HAVE MORE IMPACT. SO SOMETHING WORTH NOTING. MTF //PREV DISCUSSION... 308 AM CDT CONVECTIVE CHANCES WILL BE THE MAIN FORECAST CHALLENGE THROUGH THE REST OF THE WEEK AS UPPER LEVEL RIDGING DEVELOPS ACROSS THE MIDWEST AND GREAT LAKES. EARLY MORNING WATER VAPOR SHOWS A CLOSED UPPER LOW SPINNING NORTHWARD ACROSS WESTERN ONTARIO WITH AN ASSOCIATED SURFACE LOW FOLLOWING ALONG. A FRONTAL BOUNDARY ARCS EAST THEN SOUTH THEN SOUTHWEST FROM THE LOW ACROSS LOWER MICHIGAN AND INTO CENTRAL ILLINOIS. THE NEXT FEATURE OF INTEREST IS A LONGWAVE UPPER TROUGH SPREADING ACROSS THE WESTERN U.S. WITH SEVERAL EMBEDDED WAVES TRAVERSING THE SOUTHWESTERLY FLOW AROUND THE BASE AND TO ITS EAST. THIS WILL AID THE DEVELOPMENT OF LOW PRESSURE ACROSS THE PLAINS AND RESULT IN THE NORTHWARD MOVEMENT OF A FRONTAL BOUNDARY INTO THE UPPER MISSISSIPPI RIVER VALLEY INTO TONIGHT. THE LARGER SCALE TROUGH WILL TAKE ITS TIME MOVING ACROSS THE ROCKIES AND EVENTUALLY THE UPPER MIDWEST THROUGH THE REST OF THE WEEK. TODAY AND THIS EVENING...THE LONGWAVE UPPER TROUGH MOVING INTO THE WESTERN U.S. WILL MAKE SLOW PROGRESS TODAY BUT ENERGY WILL EJECT NORTHEASTWARD FROM ITS BASE AND HELP TO AMPLIFY UPPER RIDGING ACROSS THE CENTRAL U.S. THE COOL FRONTAL BOUNDARY TO THE SOUTH WILL MORE OR LESS WASH OUT AS SURFACE LOW PRESSURE ORGANIZES ACROSS THE NORTHERN HIGH PLAINS AND A WARM FRONT DEVELOPS TO ITS EAST. SOUTHWESTERLY FLOW WILL STRENGTHEN FROM THE SOUTHERN PLAINS TO THE WESTERN GREAT LAKES THROUGH THE DAY ALLOWING FOR STRONG WARM ADVECTION WHICH WILL RESULT IN H85 TEMPS INCREASING FROM AROUND +14 ACROSS THE LOCAL AREA THIS MORNING TO +18 OR BETTER BY TONIGHT. A VERY WARM DAY IS THEREFORE EXPECTED ACROSS THE AREA WITH HIGHS INTO THE UPPER 80S. AN INITIALLY WEAK PRESSURE GRADIENT WILL SUPPORT LIGHT WINDS THROUGH EARLY AFTERNOON ALLOWING A LAKE BREEZE TO SET UP WHICH WILL BRING SOME COOLING TO IMMEDIATE LAKE SHORE AREAS AND A BIT FURTHER INLAND ACROSS LAKE COUNTY ILLINOIS. DAYTIME HIGHS FOR THESE AREAS WILL LIKELY STILL BE QUITE WARM GIVEN THE WARM START TO THE DAY...BUT LATE AFTERNOON TEMPS WILL LIKELY CUT BACK INTO THE 70S IF NOT A BIT COOLER IN SPOTS. AN INFLUX OF BETTER MOISTURE WILL ARRIVE LATER TODAY AND CONTINUE INTO TONIGHT FROM THE SOUTHWEST. THEREFORE IT WILL BE INCREASINGLY HUMID THROUGH THE AFTERNOON AND MORE SO THIS EVENING. CHANCES FOR THUNDERSTORMS TODAY DO NOT LOOK GREAT BUT WATER VAPOR SHOWS SEVERAL SUBTLE WAVES MOVING NORTHEAST ACROSS OKLAHOMA/KANSAS WHICH WILL MOVE INTO THE SOUTHERN CWA LATE THIS AFTERNOON OR EARLY THIS EVENING. THIS...COMBINED WITH THE INFLUX OF BETTER THETA-E AIR AND WARM ASCENT ALREADY IN PLACE...AS WELL AS LITTLE IF ANY CAPPING BASED ON FORECAST SOUNDINGS...MAY SUPPORT ISOLATED/SCATTERED THUNDERSTORM DEVELOPMENT. GIVEN THE NUMBER OF LARGER SCALE FACTORS SUPPORTING CONVECTION WILL INCREASE THE AREA OF SLIGHT POPS ACROSS SOUTHERN/EASTERN AREAS LATE THIS AFTERNOON AND THIS EVENING. LATER TONIGHT AND TUESDAY...AS NOTED ABOVE...LOW PRESSURE WILL ORGANIZE ACROSS THE NORTHERN PLAINS AND PUSH A WARM FRONTAL BOUNDARY NORTHWARD ACROSS IOWA AND MINNESOTA AS UPPER LEVEL ENERGY PUSHES ACROSS THAT AREA. SEVERE THUNDERSTORMS ARE EXPECTED TO DEVELOP ACROSS SOUTH DAKOTA/IOWA/MINNESOTA THIS AFTERNOON AND ORGANIZE INTO AN MCS BY EVENING AS THE LOW LEVEL JET DEVELOPS ACROSS IOWA AND INTO FAR SOUTHERN MINNESOTA. THE LOW LEVEL JET WILL SHIFT MORE SOUTHWESTERLY INTO THE OVERNIGHT BRINGING A STEADY FEED OF MOISTURE INTO NORTHERN ILLINOIS AND CENTRAL/SOUTHERN WISCONSIN. 850-300 MB THICKNESS RIDGE STRETCHES FROM SOUTHWEST IOWA TO WESTERN LAKE SUPERIOR OVERNIGHT RESULTING IN A NORTHWEST TO SOUTHWEST ORIENTATION OF THE THICKNESS GRADIENT ACROSS MUCH OF WISCONSIN AND ILLINOIS. THIS AND THE SHIFTING OF THE LOW LEVEL JET TO A MORE SOUTHWESTERLY ORIENTATION SHIFTING THE BETTER MOISTURE TRANSPORT SUPPORT AN OVERALL EAST TO SOUTHEAST MOVEMENT OF WHATEVER MCS RESULTS FROM THE AFTERNOON/EVENING CONVECTION. THIS MAY BE MANIFESTED AS MORE OF A SOUTHWARD DEVELOPMENT VS. STORM MOTION GIVEN THAT BETTER MOISTURE WILL BE TO THE SOUTH AND THE INSTABILITY GRADIENT IS EXPECTED TO BE ORIENTED FROM NORTHWEST TO SOUTHEAST ACROSS CENTRAL/SOUTHERN WISCONSIN. IN ADDITION...BACKWARD PROPAGATING CORFIDI VECTORS SUPPORT THIS SOUTHWARD EXPANSION IDEA. HIGH RES GUIDANCE SHOWS A MYRIAD OF SOLUTIONS SO AT THIS TIME RANGE PREFER TO LEAN MORE HEAVILY ON THE LARGER SCALE ELEMENTS AND CONCEPTUAL MODELS. THIS THINKING SUPPORTS MUCH OF THE CONVECTION BEING ACROSS WISCONSIN BUT SEE ENOUGH SUPPORT FOR SOME SORT OF A SOUTHWARD EXPANSION/PROPAGATION OVERNIGHT WITH ANOTHER QUESTION BEING HOW FAR SOUTH AS WELL AS TIMING. WILL TWEAK POPS FOR TONIGHT AND TUESDAY MORNING TO SHOW A SLIGHTLY GREATER COVERAGE OF POPS GENERALLY ALONG AND NORTH OF I-80. HEAVY RAIN AND EVEN SOME DAMAGING WIND GUSTS WOULD BE THE MAIN THREATS. THE UPPER RIDGING WILL BECOME BETTER ESTABLISHED TUESDAY. WHATEVER CONVECTION IS AROUND IN THE MORNING WILL LIKELY END AND IT APPEARS THAT THE REST OF TUESDAY MAY BE DRY WITH THE FOCUS FOR CONVECTION TO THE NORTH. HOWEVER...THIS MAY ALSO BE DEPENDENT ON WHAT PLAYS OUT TUESDAY MORNING IN TERMS OF LEFTOVER BOUNDARIES ETC. THAT MAY BE ABLE TO TRIGGER ISOLD/SCATTERED CONVECTION LATER TUESDAY AS WE WILL STILL BE UNSTABLE. UPSTREAM CONVECTION ACROSS MN/IA/WI LATER TUESDAY MAY BE ABLE TO WORK ITS WAY INTO THE NORTHERN CWA AGAIN TUESDAY NIGHT...WITH HEAVY RAIN AND DAMAGING WIND POTENTIAL. OTHERWISE A STRONGER SOUTHWESTERLY FLOW WILL BE IN PLACE AS LOW PRESSURE REMAINS ACROSS THE NORTHERN PLAINS SO A LAKE BREEZE LOOKS UNLIKELY SO EVEN LAKESHORE AREAS SHOULD WARM INTO THE 80...WITH HIGHS NEAR 90 ELSEWHERE WITH A RATHER STICKY AIRMASS IN PLACE. WEDNESDAY AND BEYOND...SURFACE LOW PRESSURE WILL CONTINUE TO BE POSITIONED ACROSS THE CENTRAL AND NORTHERN PLAINS WITH A STATIONARY FRONT STRETCHING EASTWARD ACROSS CENTRAL OR SOUTHERN WISCONSIN. THE LONGWAVE UPPER TROUGH WILL STILL BE TO THE WEST AS WELL SO IMPULSES ARE LIKELY TO EMANATE NORTHEASTWARD UP THE RIDGE OVER THE UPPER MIDWEST/WESTERN GREAT LAKES. THE POSITION OF THE FRONT WILL LIKELY DRIVE WHERE THE CONVECTION WILL BE FOCUSED WEDNESDAY BUT LESS ORGANIZED CONVECTION MAY OCCUR ACROSS A LARGER AREA...ESPECIALLY IN CONJUNCTION WITH ANY SUBTLE UPPER WAVES. THE UPPER TROUGH FINALLY STARTS TO LIFT NORTHEASTWARD INTO THE NORTHERN PLAINS LATER THURSDAY TAKING SURFACE LOW PRESSURE WITH IT ALONG...WHICH WILL IN TURN PUSH A COLD FRONT EASTWARD ACROSS THE AREA FRIDAY. THE ORIGINAL STATIONARY BOUNDARY MAY SETTLE SOUTHWARD INTO THE AREA AS THIS OCCURS SO CONVECTION WILL BE POSSIBLE ACROSS THE LOCAL AREA THURSDAY AND THURSDAY NIGHT...WITH THE COLD FRONT POTENTIALLY DRIVING CONVECTION FRIDAY MORNING. HOWEVER...THIS WILL BE ANOTHER SITUATION WHERE THE LARGER SCALE FORCING WILL BE WELL TO THE NORTHWEST AND THE FRONT WILL BE WEAKENING SO CONVECTIVE DEVELOPMENT MAY BE LIMITED. THE UPPER LOW MAY THEN MOVE EASTWARD BREAKING DOWN THE RIDGE INTO THE WEEKEND. OVERALL THE REST OF THE WEEK LOOKS POTENTIALLY ACTIVE BUT MUCH OF THE BETTER ORGANIZED CONVECTION WILL NEED TO BE BETTER IDENTIFIED AT A SHORTER TIME RANGE AS THE LOCATION OF KEY FEATURES WILL LARGELY DRIVE THE OUTCOME. WITH A MOIST UNSTABLE ATMOSPHERE IN PLACE LESS ORGANIZED CONVECTION WILL PROBABLY OCCUR AT TIMES. TEMPS LOOK TO MODERATE FROM WEDNESDAY ONWARD...WITH COOLER TEMPS MORE LIKELY INTO THE WEEKEND AS THE RIDGE BREAKS DOWN AND THE COOL FRONT PASSES. MDB && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 18Z... * A LAKE BREEZE IS PSBL TODAY WITH WINDS TURNING EAST BEHIND IT AT ORD. * CHC TSRA TONIGHT. * SW WINDS GUSTING TO ARND 25 KT TOMORROW. JEE //DISCUSSION...UPDATED 18Z... THIS IS A MESSY FORECAST PERIOD WITH GUIDANCE SHOWING MANY DIFFERENT SOLUTIONS. HIGH PRESSURE IS OVER THE SOUTHEAST U.S. WHILE A LOW IS OVER NORTHWEST ONTARIO. A WEAK BOUNDARY IS ALSO OVER SOUTHERN ILLINOIS. STORMS ARE FIRING ALONG THE BOUNDARY IN NORTHEAST MISSOURI AND MOST GUIDANCE IS NOT HANDLING THE CURRENT CONVECTION WELL. THE MAIN UPPER LEVEL FORCING STRETCHES FROM IOWA THROUGH MINNESOTA AND IT WILL PASS TO OUR NORTH. THINKING THE MAIN AREA OF CONVECTION WILL PASS TO OUR NORTH BUT COULD SEE THE SOUTHERN END OF THE CONVECTIVE COMPLEX CLIP NORTHERN IL. GUIDANCE IS ALL OVER THE BOARD IN REGARDS TO TIMING AND LOCATION...BUT THE TREND HAS BEEN TO SLOW DOWN THE SYSTEM. AS SUCH PUSHED THE PROB30 BACK BY ANOTHER HOUR IN ALL OF THE TAFS. SOME MODELS FEATURE SCATTERED CONVECTION LINGERING THROUGH MID MORNING TOMORROW...PRIMARILY FOR RFD. LEFT ANY MENTION OF CONVECTION OUT OF THE TAF THOUGH DUE TO VERY LOW CONFIDENCE. FOR WINDS...A LAKE BREEZE IS OVER NORTHERN COOK AND LAKE COUNTIES AND IT IS REMAINING RELATIVELY STATIONARY NOW. THE LATEST OBS INDICATE SW WINDS ARE GUSTING SO THINKING THE LAKE BREEZE WILL CONTINUE TO STRUGGLE. BASED ON ITS LOCATION...THE BREEZE WILL NOT IMPACT MDW. KEPT THE BREEZE IN AT ORD BUT PUSHED THE TIMING BACK. STILL HAVE LOW CONFIDENCE THAT THE LAKE BREEZE WILL IMPACT ORD. SW WINDS ARE EXPECTED TONIGHT WITH SUSTAINED SPEEDS OF 10 TO 15 KT. SW WINDS THEN GUST TO ARND 25 KT TOMORROW. JEE //ORD AND MDW CONFIDENCE...UPDATED 18Z... * LOW CONFIDENCE IN LAKE BREEZE MAKING IT THROUGH ORD AND TIMING. HIGH CONFIDENCE THAT THE LAKE BREEZE WILL NOT IMPACT MDW. * HIGH CONFIDENCE IN THUNDERSTORMS DEVELOPING THIS EVENING ACROSS THE UPPER MIDWEST...LOW CONFIDENCE ON EXACT PLACEMENT AND TIMING. * HIGH CONFIDENCE IN ALL OTHER FORECAST PARAMETERS. JEE //OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z... TUESDAY NIGHT THROUGH SUNDAY...PRIMARILY VFR WITH PERIODIC CHANCES FOR THUNDERSTORMS. BMD && .MARINE... 250 AM CDT AN ACTIVE PERIOD OF WEATHER IS EXPECTED ACROSS LAKE MICHIGAN FOR THE UPCOMING WEEK. TODAY...LOW PRESSURE WILL LIFT ACROSS ONTARIO LIFTING A WARM FRONT ACROSS LAKE MICHIGAN WITH SOUTH TO SOUTHWEST WINDS OVERSPREADING THE ENTIRE LAKE. AS THE LOW CONTINUES EAST TO THE MARITIME PROVINCES LATE TUESDAY...THE COLD FRONT WILL VERY SLOWLY SAG BACK SOUTH ACROSS LAKE MICHIGAN...THEN BEGIN TO SLOWLY LIFT BACK NORTH TOWARDS THE END OF THE WEEK AS ANOTHER LOW LIFTS ACROSS THE NORTHERN PLAINS. EACH DAY THERE WILL BE CHANCES FOR THUNDERSTORMS TO DEVELOP NEAR THE FRONT INCLUDING OVER PORTIONS OF LAKE MICHIGAN...AND SOME OF THESE STORMS COULD BECOME LARGER THUNDERSTORMS COMPLEXES THAT WILL CREATE A LOT OF VARIABILITY IN THE WIND FIELD. IN ADDITION...MID 60 AND EVEN 70 DEGREE DEWPOINTS LIFTING NORTH INTO THE REGION WILL LIKELY RESULT IN FOG FORMING OVER THE RELATIVELY COOLER WATERS OF LAKE MICHIGAN. BMD && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion National Weather Service Lincoln IL 1253 PM CDT Mon Jun 16 2014 .DISCUSSION... ISSUED 943 AM CDT Mon Jun 16 2014 Scattered elevated convection continues across south-central sections of Illinois and Indiana this morning, primarily along and south of the I-70 corridor. 12z/7am WPC surface analysis indicates a weak frontal boundary draped across the region: however, it is very difficult to pick this feature out in the latest wind/dewpoint field. As the front continues to dissipate, focus for additional convection will as well. As a result, am only expecting widely scattered storms across the southern half of the KILX CWA today. Raised POPs to 40-50 along/south of I-70 this morning accordingly. Some of the high-res models show a gradual northward drift with the convection this afternoon, so have included slight chance POPs as far north as Bloomington later today. Barnes && .AVIATION... ISSUED 1253 PM CDT Mon Jun 16 2014 Widely scattered thunderstorms will develop near an ill-defined frontal boundary along a KIRK...to KTAZ...to KLWV line this afternoon. While this activity may tend to develop/drift northward later this afternoon, think areal coverage will remain low enough to keep mention out of TAFs at this time. Fairly robust Cu-field has already formed, with SCT-BKN clouds at around 3500ft expected through the afternoon. Any storms that fire will be diurnal in nature and will dissipate toward sunset, with mostly clear skies tonight into Tuesday morning. Winds will be southerly at around 10kt this afternoon and tonight, then will become southwesterly with gusts over 20kt on Tuesday. Barnes && .PREV DISCUSSION... ISSUED 330 AM CDT Mon Jun 16 2014 SHORT TERM...Today through Wednesday night Summer weather to prevail this week as temperatures warm into the upper 80s and lower 90s through Thu with moist dewpoints in the upper 60s and lower 70s. 00Z models have trended further north with convection chances through Wed with strong upper level ridge building across the eastern states into Wed. Radar mosaic shows isolated showers and thunderstorms developing past few hours south of I-72 with weakening front moving se into central IL and short wave to push east into central/southern IN during the morning. Airmass is unstable today especially this afternoon and feel this to support more redevelopment of isolated convection from I-72 south. HRRR and RAP suggests this redevelopment this afternoon over central and southern counties. Highs in the upper 80s to near 90F and humid dewpoints in the upper 60s to lower 70s. Convection chances then shift into IA/WI and northern IL tonight through Wed with stronger focus of low level jet and closer to upper level lows over northern tier states. SPC has slight risk nw of Knox and Stark counties tonight and keeps slight risk north of I-88 on Tue & Tue night. Carried just slight chance of convection over areas north of Peoria tonight through Wed morning. Then increase convection chances Wed afternoon and Wed night and especially Thu into Fri with strong upper level low moving into the northern plains and upper MS river valley and pushing a front back south late this week. SPC has slight risk of severe storms late Wed afternoon and Wed night north of Peoria over Knox, Stark and Marshall counties. Highs in the upper 80s and lower 90s through Thu and then starts cooling off a bit late this week and into the weekend. LONG TERM...Thursday through Sunday Stayed close to Allblend for weather from Thu through Sunday with daily chances of showers and thunderstorms, though perhaps a break around Sat night. Highs still in the 80s this weekend and then cooler on Monday. 07 && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS CHICAGO/ROMEOVILLE IL
1125 AM CDT MON JUN 16 2014 .DISCUSSION... 1123 AM CDT NO MAJOR CHANGES MADE TO THIS AFTERNOONS FORECAST. VISIBLE SATELLITE AND SURFACE OBSERVATIONS INDICATE THE INFLUX OF RICH LOW-LEVEL MOISTURE IS ADVANCING NORTHWARD ACROSS NORTHERN MO/CENTRAL IL. CUMULUS HAS DEVELOPED ACROSS THE SOUTHERN CWA AND RAP SOUNDINGS INDICATE LITTLE IN THE WAY OF CINH TO THE LFC...WHERE AROUND 1500-2000 J/KG OF SBCAPE IS PRESENT ABOVE. WHILE NOTHING OF PARTICULAR NOTE IS SEEN ON WATER VAPOR SATELLITE UPSTREAM INTO MO...IT MAY NOT TAKE TOO MUCH TO TRIGGER ISOLATED STORMS BY MID-AFTERNOON IN JUST THE GENERAL LOW-LEVEL WAA FLOW ACROSS THE REGION. WITH THE HIGH AMOUNT OF CAPE...THERE IS A CONDITIONAL RISK OF A STRONG TO SEVERE STORM OR TWO. THE FORECAST FOR TONIGHT REMAINS TRICKY. CONVECTION NEAR THE NE/IA BORDER IS PRIMARILY ELEVATED AND NOT REALLY CONGEALING OR BECOMING ROOTED LOWER AT THIS TIME...ALTHOUGH MAY BECOME A LITTLE MORE FAVORABLE IN TIME /SEE SPC MCD/. UPSCALE GROWTH IS EXPECTED INTO SOUTHERN MN WITH EVENTUAL CONGEALING INTO AN MCS THIS EVE INTO OVERNIGHT...WHICH A HIGH AMOUNT OF CONVECTIVE-ALLOWING GUIDANCE SHOWS. WHILE MUCH OF THE GUIDANCE DOES BRING THE BRUNT OF THAT NORTH OF THE AREA...THE PATTERN...SLOPE OF THE INSTABILITY GRADIENT...AND OBSERVATIONAL TRENDS WOULD INDICATE THAT MAYBE THE SUITE OF GUIDANCE IS TOO FAR NORTH...AND AT LEAST THE SOUTHERN PORTION OF THE COMPLEX...OR WHAT BACKBUILDS AGAINST THE LOW- LEVEL JET NOSE WOULD EVOLVE INTO FAR NORTHERN IL LATE TONIGHT. THIS WOULD GREATLY INFLUENCE TEMPERATURES AND HEAT INDICES...AS WELL AS CONVECTIVE REDEVELOPMENT POTENTIAL...ON TUESDAY. NEEDLESS TO SAY FORECAST CONFIDENCE ON TUESDAY WILL REMAIN MAINLY LOW. IF NO TO LITTLE INFLUENCE OF CLOUDS/STORMS LATE TONIGHT AND EARLY TUESDAY...HEAT INDEX READINGS OF 95 TO 100 COULD ENCOMPASS MUCH OF THE FORECAST AREA...INCLUDING CHICAGO. WHILE NOT ADVISORY CRITERIA...THE FIRST READINGS THAT WARM IN A SEASON CAN HAVE MORE IMPACT. SO SOMETHING WORTH NOTING. MTF && .PREV DISCUSSION... 308 AM CDT CONVECTIVE CHANCES WILL BE THE MAIN FORECAST CHALLENGE THROUGH THE REST OF THE WEEK AS UPPER LEVEL RIDGING DEVELOPS ACROSS THE MIDWEST AND GREAT LAKES. EARLY MORNING WATER VAPOR SHOWS A CLOSED UPPER LOW SPINNING NORTHWARD ACROSS WESTERN ONTARIO WITH AN ASSOCIATED SURFACE LOW FOLLOWING ALONG. A FRONTAL BOUNDARY ARCS EAST THEN SOUTH THEN SOUTHWEST FROM THE LOW ACROSS LOWER MICHIGAN AND INTO CENTRAL ILLINOIS. THE NEXT FEATURE OF INTEREST IS A LONGWAVE UPPER TROUGH SPREADING ACROSS THE WESTERN U.S. WITH SEVERAL EMBEDDED WAVES TRAVERSING THE SOUTHWESTERLY FLOW AROUND THE BASE AND TO ITS EAST. THIS WILL AID THE DEVELOPMENT OF LOW PRESSURE ACROSS THE PLAINS AND RESULT IN THE NORTHWARD MOVEMENT OF A FRONTAL BOUNDARY INTO THE UPPER MISSISSIPPI RIVER VALLEY INTO TONIGHT. THE LARGER SCALE TROUGH WILL TAKE ITS TIME MOVING ACROSS THE ROCKIES AND EVENTUALLY THE UPPER MIDWEST THROUGH THE REST OF THE WEEK. TODAY AND THIS EVENING...THE LONGWAVE UPPER TROUGH MOVING INTO THE WESTERN U.S. WILL MAKE SLOW PROGRESS TODAY BUT ENERGY WILL EJECT NORTHEASTWARD FROM ITS BASE AND HELP TO AMPLIFY UPPER RIDGING ACROSS THE CENTRAL U.S. THE COOL FRONTAL BOUNDARY TO THE SOUTH WILL MORE OR LESS WASH OUT AS SURFACE LOW PRESSURE ORGANIZES ACROSS THE NORTHERN HIGH PLAINS AND A WARM FRONT DEVELOPS TO ITS EAST. SOUTHWESTERLY FLOW WILL STRENGTHEN FROM THE SOUTHERN PLAINS TO THE WESTERN GREAT LAKES THROUGH THE DAY ALLOWING FOR STRONG WARM ADVECTION WHICH WILL RESULT IN H85 TEMPS INCREASING FROM AROUND +14 ACROSS THE LOCAL AREA THIS MORNING TO +18 OR BETTER BY TONIGHT. A VERY WARM DAY IS THEREFORE EXPECTED ACROSS THE AREA WITH HIGHS INTO THE UPPER 80S. AN INITIALLY WEAK PRESSURE GRADIENT WILL SUPPORT LIGHT WINDS THROUGH EARLY AFTERNOON ALLOWING A LAKE BREEZE TO SET UP WHICH WILL BRING SOME COOLING TO IMMEDIATE LAKE SHORE AREAS AND A BIT FURTHER INLAND ACROSS LAKE COUNTY ILLINOIS. DAYTIME HIGHS FOR THESE AREAS WILL LIKELY STILL BE QUITE WARM GIVEN THE WARM START TO THE DAY...BUT LATE AFTERNOON TEMPS WILL LIKELY CUT BACK INTO THE 70S IF NOT A BIT COOLER IN SPOTS. AN INFLUX OF BETTER MOISTURE WILL ARRIVE LATER TODAY AND CONTINUE INTO TONIGHT FROM THE SOUTHWEST. THEREFORE IT WILL BE INCREASINGLY HUMID THROUGH THE AFTERNOON AND MORE SO THIS EVENING. CHANCES FOR THUNDERSTORMS TODAY DO NOT LOOK GREAT BUT WATER VAPOR SHOWS SEVERAL SUBTLE WAVES MOVING NORTHEAST ACROSS OKLAHOMA/KANSAS WHICH WILL MOVE INTO THE SOUTHERN CWA LATE THIS AFTERNOON OR EARLY THIS EVENING. THIS...COMBINED WITH THE INFLUX OF BETTER THETA-E AIR AND WARM ASCENT ALREADY IN PLACE...AS WELL AS LITTLE IF ANY CAPPING BASED ON FORECAST SOUNDINGS...MAY SUPPORT ISOLATED/SCATTERED THUNDERSTORM DEVELOPMENT. GIVEN THE NUMBER OF LARGER SCALE FACTORS SUPPORTING CONVECTION WILL INCREASE THE AREA OF SLIGHT POPS ACROSS SOUTHERN/EASTERN AREAS LATE THIS AFTERNOON AND THIS EVENING. LATER TONIGHT AND TUESDAY...AS NOTED ABOVE...LOW PRESSURE WILL ORGANIZE ACROSS THE NORTHERN PLAINS AND PUSH A WARM FRONTAL BOUNDARY NORTHWARD ACROSS IOWA AND MINNESOTA AS UPPER LEVEL ENERGY PUSHES ACROSS THAT AREA. SEVERE THUNDERSTORMS ARE EXPECTED TO DEVELOP ACROSS SOUTH DAKOTA/IOWA/MINNESOTA THIS AFTERNOON AND ORGANIZE INTO AN MCS BY EVENING AS THE LOW LEVEL JET DEVELOPS ACROSS IOWA AND INTO FAR SOUTHERN MINNESOTA. THE LOW LEVEL JET WILL SHIFT MORE SOUTHWESTERLY INTO THE OVERNIGHT BRINGING A STEADY FEED OF MOISTURE INTO NORTHERN ILLINOIS AND CENTRAL/SOUTHERN WISCONSIN. 850-300 MB THICKNESS RIDGE STRETCHES FROM SOUTHWEST IOWA TO WESTERN LAKE SUPERIOR OVERNIGHT RESULTING IN A NORTHWEST TO SOUTHWEST ORIENTATION OF THE THICKNESS GRADIENT ACROSS MUCH OF WISCONSIN AND ILLINOIS. THIS AND THE SHIFTING OF THE LOW LEVEL JET TO A MORE SOUTHWESTERLY ORIENTATION SHIFTING THE BETTER MOISTURE TRANSPORT SUPPORT AN OVERALL EAST TO SOUTHEAST MOVEMENT OF WHATEVER MCS RESULTS FROM THE AFTERNOON/EVENING CONVECTION. THIS MAY BE MANIFESTED AS MORE OF A SOUTHWARD DEVELOPMENT VS. STORM MOTION GIVEN THAT BETTER MOISTURE WILL BE TO THE SOUTH AND THE INSTABILITY GRADIENT IS EXPECTED TO BE ORIENTED FROM NORTHWEST TO SOUTHEAST ACROSS CENTRAL/SOUTHERN WISCONSIN. IN ADDITION...BACKWARD PROPAGATING CORFIDI VECTORS SUPPORT THIS SOUTHWARD EXPANSION IDEA. HIGH RES GUIDANCE SHOWS A MYRIAD OF SOLUTIONS SO AT THIS TIME RANGE PREFER TO LEAN MORE HEAVILY ON THE LARGER SCALE ELEMENTS AND CONCEPTUAL MODELS. THIS THINKING SUPPORTS MUCH OF THE CONVECTION BEING ACROSS WISCONSIN BUT SEE ENOUGH SUPPORT FOR SOME SORT OF A SOUTHWARD EXPANSION/PROPAGATION OVERNIGHT WITH ANOTHER QUESTION BEING HOW FAR SOUTH AS WELL AS TIMING. WILL TWEAK POPS FOR TONIGHT AND TUESDAY MORNING TO SHOW A SLIGHTLY GREATER COVERAGE OF POPS GENERALLY ALONG AND NORTH OF I-80. HEAVY RAIN AND EVEN SOME DAMAGING WIND GUSTS WOULD BE THE MAIN THREATS. THE UPPER RIDGING WILL BECOME BETTER ESTABLISHED TUESDAY. WHATEVER CONVECTION IS AROUND IN THE MORNING WILL LIKELY END AND IT APPEARS THAT THE REST OF TUESDAY MAY BE DRY WITH THE FOCUS FOR CONVECTION TO THE NORTH. HOWEVER...THIS MAY ALSO BE DEPENDENT ON WHAT PLAYS OUT TUESDAY MORNING IN TERMS OF LEFTOVER BOUNDARIES ETC. THAT MAY BE ABLE TO TRIGGER ISOLD/SCATTERED CONVECTION LATER TUESDAY AS WE WILL STILL BE UNSTABLE. UPSTREAM CONVECTION ACROSS MN/IA/WI LATER TUESDAY MAY BE ABLE TO WORK ITS WAY INTO THE NORTHERN CWA AGAIN TUESDAY NIGHT...WITH HEAVY RAIN AND DAMAGING WIND POTENTIAL. OTHERWISE A STRONGER SOUTHWESTERLY FLOW WILL BE IN PLACE AS LOW PRESSURE REMAINS ACROSS THE NORTHERN PLAINS SO A LAKE BREEZE LOOKS UNLIKELY SO EVEN LAKESHORE AREAS SHOULD WARM INTO THE 80...WITH HIGHS NEAR 90 ELSEWHERE WITH A RATHER STICKY AIRMASS IN PLACE. WEDNESDAY AND BEYOND...SURFACE LOW PRESSURE WILL CONTINUE TO BE POSITIONED ACROSS THE CENTRAL AND NORTHERN PLAINS WITH A STATIONARY FRONT STRETCHING EASTWARD ACROSS CENTRAL OR SOUTHERN WISCONSIN. THE LONGWAVE UPPER TROUGH WILL STILL BE TO THE WEST AS WELL SO IMPULSES ARE LIKELY TO EMANATE NORTHEASTWARD UP THE RIDGE OVER THE UPPER MIDWEST/WESTERN GREAT LAKES. THE POSITION OF THE FRONT WILL LIKELY DRIVE WHERE THE CONVECTION WILL BE FOCUSED WEDNESDAY BUT LESS ORGANIZED CONVECTION MAY OCCUR ACROSS A LARGER AREA...ESPECIALLY IN CONJUNCTION WITH ANY SUBTLE UPPER WAVES. THE UPPER TROUGH FINALLY STARTS TO LIFT NORTHEASTWARD INTO THE NORTHERN PLAINS LATER THURSDAY TAKING SURFACE LOW PRESSURE WITH IT ALONG...WHICH WILL IN TURN PUSH A COLD FRONT EASTWARD ACROSS THE AREA FRIDAY. THE ORIGINAL STATIONARY BOUNDARY MAY SETTLE SOUTHWARD INTO THE AREA AS THIS OCCURS SO CONVECTION WILL BE POSSIBLE ACROSS THE LOCAL AREA THURSDAY AND THURSDAY NIGHT...WITH THE COLD FRONT POTENTIALLY DRIVING CONVECTION FRIDAY MORNING. HOWEVER...THIS WILL BE ANOTHER SITUATION WHERE THE LARGER SCALE FORCING WILL BE WELL TO THE NORTHWEST AND THE FRONT WILL BE WEAKENING SO CONVECTIVE DEVELOPMENT MAY BE LIMITED. THE UPPER LOW MAY THEN MOVE EASTWARD BREAKING DOWN THE RIDGE INTO THE WEEKEND. OVERALL THE REST OF THE WEEK LOOKS POTENTIALLY ACTIVE BUT MUCH OF THE BETTER ORGANIZED CONVECTION WILL NEED TO BE BETTER IDENTIFIED AT A SHORTER TIME RANGE AS THE LOCATION OF KEY FEATURES WILL LARGELY DRIVE THE OUTCOME. WITH A MOIST UNSTABLE ATMOSPHERE IN PLACE LESS ORGANIZED CONVECTION WILL PROBABLY OCCUR AT TIMES. TEMPS LOOK TO MODERATE FROM WEDNESDAY ONWARD...WITH COOLER TEMPS MORE LIKELY INTO THE WEEKEND AS THE RIDGE BREAKS DOWN AND THE COOL FRONT PASSES. MDB && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 16Z... * A LAKE BREEZE IS PSBL TODAY WITH WINDS TURNING EAST BEHIND IT. BETTER CHANCE OF EAST WINDS AT ORD THAN MDW. * CHC TSRA THIS EVENING/TONIGHT. JEE //DISCUSSION...UPDATED 12Z... MOST OF TODAY WILL BE VFR WITH MODEST SW/SSW WINDS. A FRONTAL BOUNDARY THAT PUSHED ACROSS THE AREA YESTERDAY NOW LIES ACROSS CENTRAL ILLINOIS AND MAY BE THE FOCUS FOR A FEW ISOLATED THUNDERSTORMS THIS AFTERNOON...HOWEVER THIS SHOULD REMAIN CONFINED TO AREAS SOUTH OF I-80. WINDS SHOULD GENERALLY BE OUT OF THE SOUTHWEST TO SOUTH-SOUTHWEST TODAY AT OR BELOW 10 KT THROUGH MID AFTERNOON. A LAKE BREEZE IS EXPECTED TO DEVELOP AND PUSH INLAND SEVERAL MILES INTO COOK COUNTY. FOR NOW ONLY THE HRRR WANTS TO PUSH THE BOUNDARY ALL THE WAY ACROSS BOTH ORD AND MDW TURNING WINDS TO THE EAST...WHILE MOST MODELS SHOW THE BOUNDARY STALLING IN THE VICINITY OF ORD AND SHY OF MDW. THE GRADIENT BEGINS TO INCREASE LATE AFTERNOON INTO THE EVENING SO EXPECT WINDS TO INCREASE AND SHOULD PUSH THE LAKE BREEZE BACK TOWARDS THE LAKE WITH SOUTHWEST FLOW RESUMING. THIS EVENING...A LOW LEVEL JET IS PROGGED TO DEVELOP AHEAD OF AN APPROACHING LOW KICKING OFF THUNDERSTORMS WHICH WILL INCREASE IN COVERAGE. MOST GLOBAL MODELS SHOW THE BULK OF THE ACTIVITY STAYING OVER WISCONSIN...HOWEVER THERE ARE HINTS THAT SOME OF THESE STORMS COULD PROPAGATE SOUTH INTO NORTHERN ILLINOIS IMPACTING THE TERMINALS LATE THIS EVENING AND OVERNIGHT. WILL MAINTAIN A PROB30 FOR NOW GIVEN THE LACK OF CERTAINTY IN THIS SCENARIO PANNING OUT. HI-RES GUIDANCE IS ALL OVER THE PLACE AND OFFERS LITTLE INSIGHT INTO HOW CONVECTION MIGHT EVOLVE THIS EVENING AND TONIGHT. BMD //ORD AND MDW CONFIDENCE...UPDATED 16Z... * LOW CONFIDENCE IN LAKE BREEZE MAKING IT THROUGH THE TERMINALS TODAY. * HIGH CONFIDENCE IN THUNDERSTORMS DEVELOPING THIS EVENING ACROSS THE UPPER MIDWEST...LOW CONFIDENCE ON EXACT PLACEMENT AND TIMING. * HIGH CONFIDENCE IN ALL OTHER FORECAST PARAMETERS. JEE //OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z... TUESDAY NIGHT THROUGH SUNDAY...PRIMARILY VFR WITH PERIODIC CHANCES FOR THUNDERSTORMS. BMD && .MARINE... 250 AM CDT AN ACTIVE PERIOD OF WEATHER IS EXPECTED ACROSS LAKE MICHIGAN FOR THE UPCOMING WEEK. TODAY...LOW PRESSURE WILL LIFT ACROSS ONTARIO LIFTING A WARM FRONT ACROSS LAKE MICHIGAN WITH SOUTH TO SOUTHWEST WINDS OVERSPREADING THE ENTIRE LAKE. AS THE LOW CONTINUES EAST TO THE MARITIME PROVINCES LATE TUESDAY...THE COLD FRONT WILL VERY SLOWLY SAG BACK SOUTH ACROSS LAKE MICHIGAN...THEN BEGIN TO SLOWLY LIFT BACK NORTH TOWARDS THE END OF THE WEEK AS ANOTHER LOW LIFTS ACROSS THE NORTHERN PLAINS. EACH DAY THERE WILL BE CHANCES FOR THUNDERSTORMS TO DEVELOP NEAR THE FRONT INCLUDING OVER PORTIONS OF LAKE MICHIGAN...AND SOME OF THESE STORMS COULD BECOME LARGER THUNDERSTORMS COMPLEXES THAT WILL CREATE A LOT OF VARIABILITY IN THE WIND FIELD. IN ADDITION...MID 60 AND EVEN 70 DEGREE DEWPOINTS LIFTING NORTH INTO THE REGION WILL LIKELY RESULT IN FOG FORMING OVER THE RELATIVELY COOLER WATERS OF LAKE MICHIGAN. BMD && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1059 AM CDT MON JUN 16 2014 .DISCUSSION... 308 AM CDT CONVECTIVE CHANCES WILL BE THE MAIN FORECAST CHALLENGE THROUGH THE REST OF THE WEEK AS UPPER LEVEL RIDGING DEVELOPS ACROSS THE MIDWEST AND GREAT LAKES. EARLY MORNING WATER VAPOR SHOWS A CLOSED UPPER LOW SPINNING NORTHWARD ACROSS WESTERN ONTARIO WITH AN ASSOCIATED SURFACE LOW FOLLOWING ALONG. A FRONTAL BOUNDARY ARCS EAST THEN SOUTH THEN SOUTHWEST FROM THE LOW ACROSS LOWER MICHIGAN AND INTO CENTRAL ILLINOIS. THE NEXT FEATURE OF INTEREST IS A LONGWAVE UPPER TROUGH SPREADING ACROSS THE WESTERN U.S. WITH SEVERAL EMBEDDED WAVES TRAVERSING THE SOUTHWESTERLY FLOW AROUND THE BASE AND TO ITS EAST. THIS WILL AID THE DEVELOPMENT OF LOW PRESSURE ACROSS THE PLAINS AND RESULT IN THE NORTHWARD MOVEMENT OF A FRONTAL BOUNDARY INTO THE UPPER MISSISSIPPI RIVER VALLEY INTO TONIGHT. THE LARGER SCALE TROUGH WILL TAKE ITS TIME MOVING ACROSS THE ROCKIES AND EVENTUALLY THE UPPER MIDWEST THROUGH THE REST OF THE WEEK. TODAY AND THIS EVENING...THE LONGWAVE UPPER TROUGH MOVING INTO THE WESTERN U.S. WILL MAKE SLOW PROGRESS TODAY BUT ENERGY WILL EJECT NORTHEASTWARD FROM ITS BASE AND HELP TO AMPLIFY UPPER RIDGING ACROSS THE CENTRAL U.S. THE COOL FRONTAL BOUNDARY TO THE SOUTH WILL MORE OR LESS WASH OUT AS SURFACE LOW PRESSURE ORGANIZES ACROSS THE NORTHERN HIGH PLAINS AND A WARM FRONT DEVELOPS TO ITS EAST. SOUTHWESTERLY FLOW WILL STRENGTHEN FROM THE SOUTHERN PLAINS TO THE WESTERN GREAT LAKES THROUGH THE DAY ALLOWING FOR STRONG WARM ADVECTION WHICH WILL RESULT IN H85 TEMPS INCREASING FROM AROUND +14 ACROSS THE LOCAL AREA THIS MORNING TO +18 OR BETTER BY TONIGHT. A VERY WARM DAY IS THEREFORE EXPECTED ACROSS THE AREA WITH HIGHS INTO THE UPPER 80S. AN INITIALLY WEAK PRESSURE GRADIENT WILL SUPPORT LIGHT WINDS THROUGH EARLY AFTERNOON ALLOWING A LAKE BREEZE TO SET UP WHICH WILL BRING SOME COOLING TO IMMEDIATE LAKE SHORE AREAS AND A BIT FURTHER INLAND ACROSS LAKE COUNTY ILLINOIS. DAYTIME HIGHS FOR THESE AREAS WILL LIKELY STILL BE QUITE WARM GIVEN THE WARM START TO THE DAY...BUT LATE AFTERNOON TEMPS WILL LIKELY CUT BACK INTO THE 70S IF NOT A BIT COOLER IN SPOTS. AN INFLUX OF BETTER MOISTURE WILL ARRIVE LATER TODAY AND CONTINUE INTO TONIGHT FROM THE SOUTHWEST. THEREFORE IT WILL BE INCREASINGLY HUMID THROUGH THE AFTERNOON AND MORE SO THIS EVENING. CHANCES FOR THUNDERSTORMS TODAY DO NOT LOOK GREAT BUT WATER VAPOR SHOWS SEVERAL SUBTLE WAVES MOVING NORTHEAST ACROSS OKLAHOMA/KANSAS WHICH WILL MOVE INTO THE SOUTHERN CWA LATE THIS AFTERNOON OR EARLY THIS EVENING. THIS...COMBINED WITH THE INFLUX OF BETTER THETA-E AIR AND WARM ASCENT ALREADY IN PLACE...AS WELL AS LITTLE IF ANY CAPPING BASED ON FORECAST SOUNDINGS...MAY SUPPORT ISOLATED/SCATTERED THUNDERSTORM DEVELOPMENT. GIVEN THE NUMBER OF LARGER SCALE FACTORS SUPPORTING CONVECTION WILL INCREASE THE AREA OF SLIGHT POPS ACROSS SOUTHERN/EASTERN AREAS LATE THIS AFTERNOON AND THIS EVENING. LATER TONIGHT AND TUESDAY...AS NOTED ABOVE...LOW PRESSURE WILL ORGANIZE ACROSS THE NORTHERN PLAINS AND PUSH A WARM FRONTAL BOUNDARY NORTHWARD ACROSS IOWA AND MINNESOTA AS UPPER LEVEL ENERGY PUSHES ACROSS THAT AREA. SEVERE THUNDERSTORMS ARE EXPECTED TO DEVELOP ACROSS SOUTH DAKOTA/IOWA/MINNESOTA THIS AFTERNOON AND ORGANIZE INTO AN MCS BY EVENING AS THE LOW LEVEL JET DEVELOPS ACROSS IOWA AND INTO FAR SOUTHERN MINNESOTA. THE LOW LEVEL JET WILL SHIFT MORE SOUTHWESTERLY INTO THE OVERNIGHT BRINGING A STEADY FEED OF MOISTURE INTO NORTHERN ILLINOIS AND CENTRAL/SOUTHERN WISCONSIN. 850-300 MB THICKNESS RIDGE STRETCHES FROM SOUTHWEST IOWA TO WESTERN LAKE SUPERIOR OVERNIGHT RESULTING IN A NORTHWEST TO SOUTHWEST ORIENTATION OF THE THICKNESS GRADIENT ACROSS MUCH OF WISCONSIN AND ILLINOIS. THIS AND THE SHIFTING OF THE LOW LEVEL JET TO A MORE SOUTHWESTERLY ORIENTATION SHIFTING THE BETTER MOISTURE TRANSPORT SUPPORT AN OVERALL EAST TO SOUTHEAST MOVEMENT OF WHATEVER MCS RESULTS FROM THE AFTERNOON/EVENING CONVECTION. THIS MAY BE MANIFESTED AS MORE OF A SOUTHWARD DEVELOPMENT VS. STORM MOTION GIVEN THAT BETTER MOISTURE WILL BE TO THE SOUTH AND THE INSTABILITY GRADIENT IS EXPECTED TO BE ORIENTED FROM NORTHWEST TO SOUTHEAST ACROSS CENTRAL/SOUTHERN WISCONSIN. IN ADDITION...BACKWARD PROPAGATING CORFIDI VECTORS SUPPORT THIS SOUTHWARD EXPANSION IDEA. HIGH RES GUIDANCE SHOWS A MYRIAD OF SOLUTIONS SO AT THIS TIME RANGE PREFER TO LEAN MORE HEAVILY ON THE LARGER SCALE ELEMENTS AND CONCEPTUAL MODELS. THIS THINKING SUPPORTS MUCH OF THE CONVECTION BEING ACROSS WISCONSIN BUT SEE ENOUGH SUPPORT FOR SOME SORT OF A SOUTHWARD EXPANSION/PROPAGATION OVERNIGHT WITH ANOTHER QUESTION BEING HOW FAR SOUTH AS WELL AS TIMING. WILL TWEAK POPS FOR TONIGHT AND TUESDAY MORNING TO SHOW A SLIGHTLY GREATER COVERAGE OF POPS GENERALLY ALONG AND NORTH OF I-80. HEAVY RAIN AND EVEN SOME DAMAGING WIND GUSTS WOULD BE THE MAIN THREATS. THE UPPER RIDGING WILL BECOME BETTER ESTABLISHED TUESDAY. WHATEVER CONVECTION IS AROUND IN THE MORNING WILL LIKELY END AND IT APPEARS THAT THE REST OF TUESDAY MAY BE DRY WITH THE FOCUS FOR CONVECTION TO THE NORTH. HOWEVER...THIS MAY ALSO BE DEPENDENT ON WHAT PLAYS OUT TUESDAY MORNING IN TERMS OF LEFTOVER BOUNDARIES ETC. THAT MAY BE ABLE TO TRIGGER ISOLD/SCATTERED CONVECTION LATER TUESDAY AS WE WILL STILL BE UNSTABLE. UPSTREAM CONVECTION ACROSS MN/IA/WI LATER TUESDAY MAY BE ABLE TO WORK ITS WAY INTO THE NORTHERN CWA AGAIN TUESDAY NIGHT...WITH HEAVY RAIN AND DAMAGING WIND POTENTIAL. OTHERWISE A STRONGER SOUTHWESTERLY FLOW WILL BE IN PLACE AS LOW PRESSURE REMAINS ACROSS THE NORTHERN PLAINS SO A LAKE BREEZE LOOKS UNLIKELY SO EVEN LAKESHORE AREAS SHOULD WARM INTO THE 80...WITH HIGHS NEAR 90 ELSEWHERE WITH A RATHER STICKY AIRMASS IN PLACE. WEDNESDAY AND BEYOND...SURFACE LOW PRESSURE WILL CONTINUE TO BE POSITIONED ACROSS THE CENTRAL AND NORTHERN PLAINS WITH A STATIONARY FRONT STRETCHING EASTWARD ACROSS CENTRAL OR SOUTHERN WISCONSIN. THE LONGWAVE UPPER TROUGH WILL STILL BE TO THE WEST AS WELL SO IMPULSES ARE LIKELY TO EMANATE NORTHEASTWARD UP THE RIDGE OVER THE UPPER MIDWEST/WESTERN GREAT LAKES. THE POSITION OF THE FRONT WILL LIKELY DRIVE WHERE THE CONVECTION WILL BE FOCUSED WEDNESDAY BUT LESS ORGANIZED CONVECTION MAY OCCUR ACROSS A LARGER AREA...ESPECIALLY IN CONJUNCTION WITH ANY SUBTLE UPPER WAVES. THE UPPER TROUGH FINALLY STARTS TO LIFT NORTHEASTWARD INTO THE NORTHERN PLAINS LATER THURSDAY TAKING SURFACE LOW PRESSURE WITH IT ALONG...WHICH WILL IN TURN PUSH A COLD FRONT EASTWARD ACROSS THE AREA FRIDAY. THE ORIGINAL STATIONARY BOUNDARY MAY SETTLE SOUTHWARD INTO THE AREA AS THIS OCCURS SO CONVECTION WILL BE POSSIBLE ACROSS THE LOCAL AREA THURSDAY AND THURSDAY NIGHT...WITH THE COLD FRONT POTENTIALLY DRIVING CONVECTION FRIDAY MORNING. HOWEVER...THIS WILL BE ANOTHER SITUATION WHERE THE LARGER SCALE FORCING WILL BE WELL TO THE NORTHWEST AND THE FRONT WILL BE WEAKENING SO CONVECTIVE DEVELOPMENT MAY BE LIMITED. THE UPPER LOW MAY THEN MOVE EASTWARD BREAKING DOWN THE RIDGE INTO THE WEEKEND. OVERALL THE REST OF THE WEEK LOOKS POTENTIALLY ACTIVE BUT MUCH OF THE BETTER ORGANIZED CONVECTION WILL NEED TO BE BETTER IDENTIFIED AT A SHORTER TIME RANGE AS THE LOCATION OF KEY FEATURES WILL LARGELY DRIVE THE OUTCOME. WITH A MOIST UNSTABLE ATMOSPHERE IN PLACE LESS ORGANIZED CONVECTION WILL PROBABLY OCCUR AT TIMES. TEMPS LOOK TO MODERATE FROM WEDNESDAY ONWARD...WITH COOLER TEMPS MORE LIKELY INTO THE WEEKEND AS THE RIDGE BREAKS DOWN AND THE COOL FRONT PASSES. MDB && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 16Z... * A LAKE BREEZE IS PSBL TODAY WITH WINDS TURNING EAST BEHIND IT. BETTER CHANCE OF EAST WINDS AT ORD THAN MDW. * CHC TSRA THIS EVENING/TONIGHT. JEE //DISCUSSION...UPDATED 12Z... MOST OF TODAY WILL BE VFR WITH MODEST SW/SSW WINDS. A FRONTAL BOUNDARY THAT PUSHED ACROSS THE AREA YESTERDAY NOW LIES ACROSS CENTRAL ILLINOIS AND MAY BE THE FOCUS FOR A FEW ISOLATED THUNDERSTORMS THIS AFTERNOON...HOWEVER THIS SHOULD REMAIN CONFINED TO AREAS SOUTH OF I-80. WINDS SHOULD GENERALLY BE OUT OF THE SOUTHWEST TO SOUTH-SOUTHWEST TODAY AT OR BELOW 10 KT THROUGH MID AFTERNOON. A LAKE BREEZE IS EXPECTED TO DEVELOP AND PUSH INLAND SEVERAL MILES INTO COOK COUNTY. FOR NOW ONLY THE HRRR WANTS TO PUSH THE BOUNDARY ALL THE WAY ACROSS BOTH ORD AND MDW TURNING WINDS TO THE EAST...WHILE MOST MODELS SHOW THE BOUNDARY STALLING IN THE VICINITY OF ORD AND SHY OF MDW. THE GRADIENT BEGINS TO INCREASE LATE AFTERNOON INTO THE EVENING SO EXPECT WINDS TO INCREASE AND SHOULD PUSH THE LAKE BREEZE BACK TOWARDS THE LAKE WITH SOUTHWEST FLOW RESUMING. THIS EVENING...A LOW LEVEL JET IS PROGGED TO DEVELOP AHEAD OF AN APPROACHING LOW KICKING OFF THUNDERSTORMS WHICH WILL INCREASE IN COVERAGE. MOST GLOBAL MODELS SHOW THE BULK OF THE ACTIVITY STAYING OVER WISCONSIN...HOWEVER THERE ARE HINTS THAT SOME OF THESE STORMS COULD PROPAGATE SOUTH INTO NORTHERN ILLINOIS IMPACTING THE TERMINALS LATE THIS EVENING AND OVERNIGHT. WILL MAINTAIN A PROB30 FOR NOW GIVEN THE LACK OF CERTAINTY IN THIS SCENARIO PANNING OUT. HI-RES GUIDANCE IS ALL OVER THE PLACE AND OFFERS LITTLE INSIGHT INTO HOW CONVECTION MIGHT EVOLVE THIS EVENING AND TONIGHT. BMD //ORD AND MDW CONFIDENCE...UPDATED 16Z... * LOW CONFIDENCE IN LAKE BREEZE MAKING IT THROUGH THE TERMINALS TODAY. * HIGH CONFIDENCE IN THUNDERSTORMS DEVELOPING THIS EVENING ACROSS THE UPPER MIDWEST...LOW CONFIDENCE ON EXACT PLACEMENT AND TIMING. * HIGH CONFIDENCE IN ALL OTHER FORECAST PARAMETERS. JEE //OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z... TUESDAY NIGHT THROUGH SUNDAY...PRIMARILY VFR WITH PERIODIC CHANCES FOR THUNDERSTORMS. BMD && .MARINE... 250 AM CDT AN ACTIVE PERIOD OF WEATHER IS EXPECTED ACROSS LAKE MICHIGAN FOR THE UPCOMING WEEK. TODAY...LOW PRESSURE WILL LIFT ACROSS ONTARIO LIFTING A WARM FRONT ACROSS LAKE MICHIGAN WITH SOUTH TO SOUTHWEST WINDS OVERSPREADING THE ENTIRE LAKE. AS THE LOW CONTINUES EAST TO THE MARITIME PROVINCES LATE TUESDAY...THE COLD FRONT WILL VERY SLOWLY SAG BACK SOUTH ACROSS LAKE MICHIGAN...THEN BEGIN TO SLOWLY LIFT BACK NORTH TOWARDS THE END OF THE WEEK AS ANOTHER LOW LIFTS ACROSS THE NORTHERN PLAINS. EACH DAY THERE WILL BE CHANCES FOR THUNDERSTORMS TO DEVELOP NEAR THE FRONT INCLUDING OVER PORTIONS OF LAKE MICHIGAN...AND SOME OF THESE STORMS COULD BECOME LARGER THUNDERSTORMS COMPLEXES THAT WILL CREATE A LOT OF VARIABILITY IN THE WIND FIELD. IN ADDITION...MID 60 AND EVEN 70 DEGREE DEWPOINTS LIFTING NORTH INTO THE REGION WILL LIKELY RESULT IN FOG FORMING OVER THE RELATIVELY COOLER WATERS OF LAKE MICHIGAN. BMD && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
850 AM CDT MON JUN 16 2014 .DISCUSSION... 308 AM CDT CONVECTIVE CHANCES WILL BE THE MAIN FORECAST CHALLENGE THROUGH THE REST OF THE WEEK AS UPPER LEVEL RIDGING DEVELOPS ACROSS THE MIDWEST AND GREAT LAKES. EARLY MORNING WATER VAPOR SHOWS A CLOSED UPPER LOW SPINNING NORTHWARD ACROSS WESTERN ONTARIO WITH AN ASSOCIATED SURFACE LOW FOLLOWING ALONG. A FRONTAL BOUNDARY ARCS EAST THEN SOUTH THEN SOUTHWEST FROM THE LOW ACROSS LOWER MICHIGAN AND INTO CENTRAL ILLINOIS. THE NEXT FEATURE OF INTEREST IS A LONGWAVE UPPER TROUGH SPREADING ACROSS THE WESTERN U.S. WITH SEVERAL EMBEDDED WAVES TRAVERSING THE SOUTHWESTERLY FLOW AROUND THE BASE AND TO ITS EAST. THIS WILL AID THE DEVELOPMENT OF LOW PRESSURE ACROSS THE PLAINS AND RESULT IN THE NORTHWARD MOVEMENT OF A FRONTAL BOUNDARY INTO THE UPPER MISSISSIPPI RIVER VALLEY INTO TONIGHT. THE LARGER SCALE TROUGH WILL TAKE ITS TIME MOVING ACROSS THE ROCKIES AND EVENTUALLY THE UPPER MIDWEST THROUGH THE REST OF THE WEEK. TODAY AND THIS EVENING...THE LONGWAVE UPPER TROUGH MOVING INTO THE WESTERN U.S. WILL MAKE SLOW PROGRESS TODAY BUT ENERGY WILL EJECT NORTHEASTWARD FROM ITS BASE AND HELP TO AMPLIFY UPPER RIDGING ACROSS THE CENTRAL U.S. THE COOL FRONTAL BOUNDARY TO THE SOUTH WILL MORE OR LESS WASH OUT AS SURFACE LOW PRESSURE ORGANIZES ACROSS THE NORTHERN HIGH PLAINS AND A WARM FRONT DEVELOPS TO ITS EAST. SOUTHWESTERLY FLOW WILL STRENGTHEN FROM THE SOUTHERN PLAINS TO THE WESTERN GREAT LAKES THROUGH THE DAY ALLOWING FOR STRONG WARM ADVECTION WHICH WILL RESULT IN H85 TEMPS INCREASING FROM AROUND +14 ACROSS THE LOCAL AREA THIS MORNING TO +18 OR BETTER BY TONIGHT. A VERY WARM DAY IS THEREFORE EXPECTED ACROSS THE AREA WITH HIGHS INTO THE UPPER 80S. AN INITIALLY WEAK PRESSURE GRADIENT WILL SUPPORT LIGHT WINDS THROUGH EARLY AFTERNOON ALLOWING A LAKE BREEZE TO SET UP WHICH WILL BRING SOME COOLING TO IMMEDIATE LAKE SHORE AREAS AND A BIT FURTHER INLAND ACROSS LAKE COUNTY ILLINOIS. DAYTIME HIGHS FOR THESE AREAS WILL LIKELY STILL BE QUITE WARM GIVEN THE WARM START TO THE DAY...BUT LATE AFTERNOON TEMPS WILL LIKELY CUT BACK INTO THE 70S IF NOT A BIT COOLER IN SPOTS. AN INFLUX OF BETTER MOISTURE WILL ARRIVE LATER TODAY AND CONTINUE INTO TONIGHT FROM THE SOUTHWEST. THEREFORE IT WILL BE INCREASINGLY HUMID THROUGH THE AFTERNOON AND MORE SO THIS EVENING. CHANCES FOR THUNDERSTORMS TODAY DO NOT LOOK GREAT BUT WATER VAPOR SHOWS SEVERAL SUBTLE WAVES MOVING NORTHEAST ACROSS OKLAHOMA/KANSAS WHICH WILL MOVE INTO THE SOUTHERN CWA LATE THIS AFTERNOON OR EARLY THIS EVENING. THIS...COMBINED WITH THE INFLUX OF BETTER THETA-E AIR AND WARM ASCENT ALREADY IN PLACE...AS WELL AS LITTLE IF ANY CAPPING BASED ON FORECAST SOUNDINGS...MAY SUPPORT ISOLATED/SCATTERED THUNDERSTORM DEVELOPMENT. GIVEN THE NUMBER OF LARGER SCALE FACTORS SUPPORTING CONVECTION WILL INCREASE THE AREA OF SLIGHT POPS ACROSS SOUTHERN/EASTERN AREAS LATE THIS AFTERNOON AND THIS EVENING. LATER TONIGHT AND TUESDAY...AS NOTED ABOVE...LOW PRESSURE WILL ORGANIZE ACROSS THE NORTHERN PLAINS AND PUSH A WARM FRONTAL BOUNDARY NORTHWARD ACROSS IOWA AND MINNESOTA AS UPPER LEVEL ENERGY PUSHES ACROSS THAT AREA. SEVERE THUNDERSTORMS ARE EXPECTED TO DEVELOP ACROSS SOUTH DAKOTA/IOWA/MINNESOTA THIS AFTERNOON AND ORGANIZE INTO AN MCS BY EVENING AS THE LOW LEVEL JET DEVELOPS ACROSS IOWA AND INTO FAR SOUTHERN MINNESOTA. THE LOW LEVEL JET WILL SHIFT MORE SOUTHWESTERLY INTO THE OVERNIGHT BRINGING A STEADY FEED OF MOISTURE INTO NORTHERN ILLINOIS AND CENTRAL/SOUTHERN WISCONSIN. 850-300 MB THICKNESS RIDGE STRETCHES FROM SOUTHWEST IOWA TO WESTERN LAKE SUPERIOR OVERNIGHT RESULTING IN A NORTHWEST TO SOUTHWEST ORIENTATION OF THE THICKNESS GRADIENT ACROSS MUCH OF WISCONSIN AND ILLINOIS. THIS AND THE SHIFTING OF THE LOW LEVEL JET TO A MORE SOUTHWESTERLY ORIENTATION SHIFTING THE BETTER MOISTURE TRANSPORT SUPPORT AN OVERALL EAST TO SOUTHEAST MOVEMENT OF WHATEVER MCS RESULTS FROM THE AFTERNOON/EVENING CONVECTION. THIS MAY BE MANIFESTED AS MORE OF A SOUTHWARD DEVELOPMENT VS. STORM MOTION GIVEN THAT BETTER MOISTURE WILL BE TO THE SOUTH AND THE INSTABILITY GRADIENT IS EXPECTED TO BE ORIENTED FROM NORTHWEST TO SOUTHEAST ACROSS CENTRAL/SOUTHERN WISCONSIN. IN ADDITION...BACKWARD PROPAGATING CORFIDI VECTORS SUPPORT THIS SOUTHWARD EXPANSION IDEA. HIGH RES GUIDANCE SHOWS A MYRIAD OF SOLUTIONS SO AT THIS TIME RANGE PREFER TO LEAN MORE HEAVILY ON THE LARGER SCALE ELEMENTS AND CONCEPTUAL MODELS. THIS THINKING SUPPORTS MUCH OF THE CONVECTION BEING ACROSS WISCONSIN BUT SEE ENOUGH SUPPORT FOR SOME SORT OF A SOUTHWARD EXPANSION/PROPAGATION OVERNIGHT WITH ANOTHER QUESTION BEING HOW FAR SOUTH AS WELL AS TIMING. WILL TWEAK POPS FOR TONIGHT AND TUESDAY MORNING TO SHOW A SLIGHTLY GREATER COVERAGE OF POPS GENERALLY ALONG AND NORTH OF I-80. HEAVY RAIN AND EVEN SOME DAMAGING WIND GUSTS WOULD BE THE MAIN THREATS. THE UPPER RIDGING WILL BECOME BETTER ESTABLISHED TUESDAY. WHATEVER CONVECTION IS AROUND IN THE MORNING WILL LIKELY END AND IT APPEARS THAT THE REST OF TUESDAY MAY BE DRY WITH THE FOCUS FOR CONVECTION TO THE NORTH. HOWEVER...THIS MAY ALSO BE DEPENDENT ON WHAT PLAYS OUT TUESDAY MORNING IN TERMS OF LEFTOVER BOUNDARIES ETC. THAT MAY BE ABLE TO TRIGGER ISOLD/SCATTERED CONVECTION LATER TUESDAY AS WE WILL STILL BE UNSTABLE. UPSTREAM CONVECTION ACROSS MN/IA/WI LATER TUESDAY MAY BE ABLE TO WORK ITS WAY INTO THE NORTHERN CWA AGAIN TUESDAY NIGHT...WITH HEAVY RAIN AND DAMAGING WIND POTENTIAL. OTHERWISE A STRONGER SOUTHWESTERLY FLOW WILL BE IN PLACE AS LOW PRESSURE REMAINS ACROSS THE NORTHERN PLAINS SO A LAKE BREEZE LOOKS UNLIKELY SO EVEN LAKESHORE AREAS SHOULD WARM INTO THE 80...WITH HIGHS NEAR 90 ELSEWHERE WITH A RATHER STICKY AIRMASS IN PLACE. WEDNESDAY AND BEYOND...SURFACE LOW PRESSURE WILL CONTINUE TO BE POSITIONED ACROSS THE CENTRAL AND NORTHERN PLAINS WITH A STATIONARY FRONT STRETCHING EASTWARD ACROSS CENTRAL OR SOUTHERN WISCONSIN. THE LONGWAVE UPPER TROUGH WILL STILL BE TO THE WEST AS WELL SO IMPULSES ARE LIKELY TO EMANATE NORTHEASTWARD UP THE RIDGE OVER THE UPPER MIDWEST/WESTERN GREAT LAKES. THE POSITION OF THE FRONT WILL LIKELY DRIVE WHERE THE CONVECTION WILL BE FOCUSED WEDNESDAY BUT LESS ORGANIZED CONVECTION MAY OCCUR ACROSS A LARGER AREA...ESPECIALLY IN CONJUNCTION WITH ANY SUBTLE UPPER WAVES. THE UPPER TROUGH FINALLY STARTS TO LIFT NORTHEASTWARD INTO THE NORTHERN PLAINS LATER THURSDAY TAKING SURFACE LOW PRESSURE WITH IT ALONG...WHICH WILL IN TURN PUSH A COLD FRONT EASTWARD ACROSS THE AREA FRIDAY. THE ORIGINAL STATIONARY BOUNDARY MAY SETTLE SOUTHWARD INTO THE AREA AS THIS OCCURS SO CONVECTION WILL BE POSSIBLE ACROSS THE LOCAL AREA THURSDAY AND THURSDAY NIGHT...WITH THE COLD FRONT POTENTIALLY DRIVING CONVECTION FRIDAY MORNING. HOWEVER...THIS WILL BE ANOTHER SITUATION WHERE THE LARGER SCALE FORCING WILL BE WELL TO THE NORTHWEST AND THE FRONT WILL BE WEAKENING SO CONVECTIVE DEVELOPMENT MAY BE LIMITED. THE UPPER LOW MAY THEN MOVE EASTWARD BREAKING DOWN THE RIDGE INTO THE WEEKEND. OVERALL THE REST OF THE WEEK LOOKS POTENTIALLY ACTIVE BUT MUCH OF THE BETTER ORGANIZED CONVECTION WILL NEED TO BE BETTER IDENTIFIED AT A SHORTER TIME RANGE AS THE LOCATION OF KEY FEATURES WILL LARGELY DRIVE THE OUTCOME. WITH A MOIST UNSTABLE ATMOSPHERE IN PLACE LESS ORGANIZED CONVECTION WILL PROBABLY OCCUR AT TIMES. TEMPS LOOK TO MODERATE FROM WEDNESDAY ONWARD...WITH COOLER TEMPS MORE LIKELY INTO THE WEEKEND AS THE RIDGE BREAKS DOWN AND THE COOL FRONT PASSES. MDB && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 14Z... * A LAKE BREEZE IS PSBL TODAY WITH WINDS TURNING EAST BEHIND IT. BETTER CHANCE OF EAST WINDS AT ORD THAN MDW. * CHC TSRA THIS EVENING/TONIGHT. JEE //DISCUSSION...UPDATED 12Z... MOST OF TODAY WILL BE VFR WITH MODEST SW/SSW WINDS. A FRONTAL BOUNDARY THAT PUSHED ACROSS THE AREA YESTERDAY NOW LIES ACROSS CENTRAL ILLINOIS AND MAY BE THE FOCUS FOR A FEW ISOLATED THUNDERSTORMS THIS AFTERNOON...HOWEVER THIS SHOULD REMAIN CONFINED TO AREAS SOUTH OF I-80. WINDS SHOULD GENERALLY BE OUT OF THE SOUTHWEST TO SOUTH-SOUTHWEST TODAY AT OR BELOW 10 KT THROUGH MID AFTERNOON. A LAKE BREEZE IS EXPECTED TO DEVELOP AND PUSH INLAND SEVERAL MILES INTO COOK COUNTY. FOR NOW ONLY THE HRRR WANTS TO PUSH THE BOUNDARY ALL THE WAY ACROSS BOTH ORD AND MDW TURNING WINDS TO THE EAST...WHILE MOST MODELS SHOW THE BOUNDARY STALLING IN THE VICINITY OF ORD AND SHY OF MDW. THE GRADIENT BEGINS TO INCREASE LATE AFTERNOON INTO THE EVENING SO EXPECT WINDS TO INCREASE AND SHOULD PUSH THE LAKE BREEZE BACK TOWARDS THE LAKE WITH SOUTHWEST FLOW RESUMING. THIS EVENING...A LOW LEVEL JET IS PROGGED TO DEVELOP AHEAD OF AN APPROACHING LOW KICKING OFF THUNDERSTORMS WHICH WILL INCREASE IN COVERAGE. MOST GLOBAL MODELS SHOW THE BULK OF THE ACTIVITY STAYING OVER WISCONSIN...HOWEVER THERE ARE HINTS THAT SOME OF THESE STORMS COULD PROPAGATE SOUTH INTO NORTHERN ILLINOIS IMPACTING THE TERMINALS LATE THIS EVENING AND OVERNIGHT. WILL MAINTAIN A PROB30 FOR NOW GIVEN THE LACK OF CERTAINTY IN THIS SCENARIO PANNING OUT. HI-RES GUIDANCE IS ALL OVER THE PLACE AND OFFERS LITTLE INSIGHT INTO HOW CONVECTION MIGHT EVOLVE THIS EVENING AND TONIGHT. BMD //ORD AND MDW CONFIDENCE...UPDATED 14Z... * LOW CONFIDENCE IN LAKE BREEZE MAKING IT THROUGH THE TERMINALS TODAY. * HIGH CONFIDENCE IN THUNDERSTORMS DEVELOPING THIS EVENING ACROSS THE UPPER MIDWEST...LOW CONFIDENCE ON EXACT PLACEMENT. * HIGH CONFIDENCE IN ALL OTHER FORECAST PARAMETERS. JEE //OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z... TUESDAY NIGHT THROUGH SUNDAY...PRIMARILY VFR WITH PERIODIC CHANCES FOR THUNDERSTORMS. BMD && .MARINE... 250 AM CDT AN ACTIVE PERIOD OF WEATHER IS EXPECTED ACROSS LAKE MICHIGAN FOR THE UPCOMING WEEK. TODAY...LOW PRESSURE WILL LIFT ACROSS ONTARIO LIFTING A WARM FRONT ACROSS LAKE MICHIGAN WITH SOUTH TO SOUTHWEST WINDS OVERSPREADING THE ENTIRE LAKE. AS THE LOW CONTINUES EAST TO THE MARITIME PROVINCES LATE TUESDAY...THE COLD FRONT WILL VERY SLOWLY SAG BACK SOUTH ACROSS LAKE MICHIGAN...THEN BEGIN TO SLOWLY LIFT BACK NORTH TOWARDS THE END OF THE WEEK AS ANOTHER LOW LIFTS ACROSS THE NORTHERN PLAINS. EACH DAY THERE WILL BE CHANCES FOR THUNDERSTORMS TO DEVELOP NEAR THE FRONT INCLUDING OVER PORTIONS OF LAKE MICHIGAN...AND SOME OF THESE STORMS COULD BECOME LARGER THUNDERSTORMS COMPLEXES THAT WILL CREATE A LOT OF VARIABILITY IN THE WIND FIELD. IN ADDITION...MID 60 AND EVEN 70 DEGREE DEWPOINTS LIFTING NORTH INTO THE REGION WILL LIKELY RESULT IN FOG FORMING OVER THE RELATIVELY COOLER WATERS OF LAKE MICHIGAN. BMD && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
638 AM CDT MON JUN 16 2014 .DISCUSSION... 308 AM CDT CONVECTIVE CHANCES WILL BE THE MAIN FORECAST CHALLENGE THROUGH THE REST OF THE WEEK AS UPPER LEVEL RIDGING DEVELOPS ACROSS THE MIDWEST AND GREAT LAKES. EARLY MORNING WATER VAPOR SHOWS A CLOSED UPPER LOW SPINNING NORTHWARD ACROSS WESTERN ONTARIO WITH AN ASSOCIATED SURFACE LOW FOLLOWING ALONG. A FRONTAL BOUNDARY ARCS EAST THEN SOUTH THEN SOUTHWEST FROM THE LOW ACROSS LOWER MICHIGAN AND INTO CENTRAL ILLINOIS. THE NEXT FEATURE OF INTEREST IS A LONGWAVE UPPER TROUGH SPREADING ACROSS THE WESTERN U.S. WITH SEVERAL EMBEDDED WAVES TRAVERSING THE SOUTHWESTERLY FLOW AROUND THE BASE AND TO ITS EAST. THIS WILL AID THE DEVELOPMENT OF LOW PRESSURE ACROSS THE PLAINS AND RESULT IN THE NORTHWARD MOVEMENT OF A FRONTAL BOUNDARY INTO THE UPPER MISSISSIPPI RIVER VALLEY INTO TONIGHT. THE LARGER SCALE TROUGH WILL TAKE ITS TIME MOVING ACROSS THE ROCKIES AND EVENTUALLY THE UPPER MIDWEST THROUGH THE REST OF THE WEEK. TODAY AND THIS EVENING...THE LONGWAVE UPPER TROUGH MOVING INTO THE WESTERN U.S. WILL MAKE SLOW PROGRESS TODAY BUT ENERGY WILL EJECT NORTHEASTWARD FROM ITS BASE AND HELP TO AMPLIFY UPPER RIDGING ACROSS THE CENTRAL U.S. THE COOL FRONTAL BOUNDARY TO THE SOUTH WILL MORE OR LESS WASH OUT AS SURFACE LOW PRESSURE ORGANIZES ACROSS THE NORTHERN HIGH PLAINS AND A WARM FRONT DEVELOPS TO ITS EAST. SOUTHWESTERLY FLOW WILL STRENGTHEN FROM THE SOUTHERN PLAINS TO THE WESTERN GREAT LAKES THROUGH THE DAY ALLOWING FOR STRONG WARM ADVECTION WHICH WILL RESULT IN H85 TEMPS INCREASING FROM AROUND +14 ACROSS THE LOCAL AREA THIS MORNING TO +18 OR BETTER BY TONIGHT. A VERY WARM DAY IS THEREFORE EXPECTED ACROSS THE AREA WITH HIGHS INTO THE UPPER 80S. AN INITIALLY WEAK PRESSURE GRADIENT WILL SUPPORT LIGHT WINDS THROUGH EARLY AFTERNOON ALLOWING A LAKE BREEZE TO SET UP WHICH WILL BRING SOME COOLING TO IMMEDIATE LAKE SHORE AREAS AND A BIT FURTHER INLAND ACROSS LAKE COUNTY ILLINOIS. DAYTIME HIGHS FOR THESE AREAS WILL LIKELY STILL BE QUITE WARM GIVEN THE WARM START TO THE DAY...BUT LATE AFTERNOON TEMPS WILL LIKELY CUT BACK INTO THE 70S IF NOT A BIT COOLER IN SPOTS. AN INFLUX OF BETTER MOISTURE WILL ARRIVE LATER TODAY AND CONTINUE INTO TONIGHT FROM THE SOUTHWEST. THEREFORE IT WILL BE INCREASINGLY HUMID THROUGH THE AFTERNOON AND MORE SO THIS EVENING. CHANCES FOR THUNDERSTORMS TODAY DO NOT LOOK GREAT BUT WATER VAPOR SHOWS SEVERAL SUBTLE WAVES MOVING NORTHEAST ACROSS OKLAHOMA/KANSAS WHICH WILL MOVE INTO THE SOUTHERN CWA LATE THIS AFTERNOON OR EARLY THIS EVENING. THIS...COMBINED WITH THE INFLUX OF BETTER THETA-E AIR AND WARM ASCENT ALREADY IN PLACE...AS WELL AS LITTLE IF ANY CAPPING BASED ON FORECAST SOUNDINGS...MAY SUPPORT ISOLATED/SCATTERED THUNDERSTORM DEVELOPMENT. GIVEN THE NUMBER OF LARGER SCALE FACTORS SUPPORTING CONVECTION WILL INCREASE THE AREA OF SLIGHT POPS ACROSS SOUTHERN/EASTERN AREAS LATE THIS AFTERNOON AND THIS EVENING. LATER TONIGHT AND TUESDAY...AS NOTED ABOVE...LOW PRESSURE WILL ORGANIZE ACROSS THE NORTHERN PLAINS AND PUSH A WARM FRONTAL BOUNDARY NORTHWARD ACROSS IOWA AND MINNESOTA AS UPPER LEVEL ENERGY PUSHES ACROSS THAT AREA. SEVERE THUNDERSTORMS ARE EXPECTED TO DEVELOP ACROSS SOUTH DAKOTA/IOWA/MINNESOTA THIS AFTERNOON AND ORGANIZE INTO AN MCS BY EVENING AS THE LOW LEVEL JET DEVELOPS ACROSS IOWA AND INTO FAR SOUTHERN MINNESOTA. THE LOW LEVEL JET WILL SHIFT MORE SOUTHWESTERLY INTO THE OVERNIGHT BRINGING A STEADY FEED OF MOISTURE INTO NORTHERN ILLINOIS AND CENTRAL/SOUTHERN WISCONSIN. 850-300 MB THICKNESS RIDGE STRETCHES FROM SOUTHWEST IOWA TO WESTERN LAKE SUPERIOR OVERNIGHT RESULTING IN A NORTHWEST TO SOUTHWEST ORIENTATION OF THE THICKNESS GRADIENT ACROSS MUCH OF WISCONSIN AND ILLINOIS. THIS AND THE SHIFTING OF THE LOW LEVEL JET TO A MORE SOUTHWESTERLY ORIENTATION SHIFTING THE BETTER MOISTURE TRANSPORT SUPPORT AN OVERALL EAST TO SOUTHEAST MOVEMENT OF WHATEVER MCS RESULTS FROM THE AFTERNOON/EVENING CONVECTION. THIS MAY BE MANIFESTED AS MORE OF A SOUTHWARD DEVELOPMENT VS. STORM MOTION GIVEN THAT BETTER MOISTURE WILL BE TO THE SOUTH AND THE INSTABILITY GRADIENT IS EXPECTED TO BE ORIENTED FROM NORTHWEST TO SOUTHEAST ACROSS CENTRAL/SOUTHERN WISCONSIN. IN ADDITION...BACKWARD PROPAGATING CORFIDI VECTORS SUPPORT THIS SOUTHWARD EXPANSION IDEA. HIGH RES GUIDANCE SHOWS A MYRIAD OF SOLUTIONS SO AT THIS TIME RANGE PREFER TO LEAN MORE HEAVILY ON THE LARGER SCALE ELEMENTS AND CONCEPTUAL MODELS. THIS THINKING SUPPORTS MUCH OF THE CONVECTION BEING ACROSS WISCONSIN BUT SEE ENOUGH SUPPORT FOR SOME SORT OF A SOUTHWARD EXPANSION/PROPAGATION OVERNIGHT WITH ANOTHER QUESTION BEING HOW FAR SOUTH AS WELL AS TIMING. WILL TWEAK POPS FOR TONIGHT AND TUESDAY MORNING TO SHOW A SLIGHTLY GREATER COVERAGE OF POPS GENERALLY ALONG AND NORTH OF I-80. HEAVY RAIN AND EVEN SOME DAMAGING WIND GUSTS WOULD BE THE MAIN THREATS. THE UPPER RIDGING WILL BECOME BETTER ESTABLISHED TUESDAY. WHATEVER CONVECTION IS AROUND IN THE MORNING WILL LIKELY END AND IT APPEARS THAT THE REST OF TUESDAY MAY BE DRY WITH THE FOCUS FOR CONVECTION TO THE NORTH. HOWEVER...THIS MAY ALSO BE DEPENDENT ON WHAT PLAYS OUT TUESDAY MORNING IN TERMS OF LEFTOVER BOUNDARIES ETC. THAT MAY BE ABLE TO TRIGGER ISOLD/SCATTERED CONVECTION LATER TUESDAY AS WE WILL STILL BE UNSTABLE. UPSTREAM CONVECTION ACROSS MN/IA/WI LATER TUESDAY MAY BE ABLE TO WORK ITS WAY INTO THE NORTHERN CWA AGAIN TUESDAY NIGHT...WITH HEAVY RAIN AND DAMAGING WIND POTENTIAL. OTHERWISE A STRONGER SOUTHWESTERLY FLOW WILL BE IN PLACE AS LOW PRESSURE REMAINS ACROSS THE NORTHERN PLAINS SO A LAKE BREEZE LOOKS UNLIKELY SO EVEN LAKESHORE AREAS SHOULD WARM INTO THE 80...WITH HIGHS NEAR 90 ELSEWHERE WITH A RATHER STICKY AIRMASS IN PLACE. WEDNESDAY AND BEYOND...SURFACE LOW PRESSURE WILL CONTINUE TO BE POSITIONED ACROSS THE CENTRAL AND NORTHERN PLAINS WITH A STATIONARY FRONT STRETCHING EASTWARD ACROSS CENTRAL OR SOUTHERN WISCONSIN. THE LONGWAVE UPPER TROUGH WILL STILL BE TO THE WEST AS WELL SO IMPULSES ARE LIKELY TO EMANATE NORTHEASTWARD UP THE RIDGE OVER THE UPPER MIDWEST/WESTERN GREAT LAKES. THE POSITION OF THE FRONT WILL LIKELY DRIVE WHERE THE CONVECTION WILL BE FOCUSED WEDNESDAY BUT LESS ORGANIZED CONVECTION MAY OCCUR ACROSS A LARGER AREA...ESPECIALLY IN CONJUNCTION WITH ANY SUBTLE UPPER WAVES. THE UPPER TROUGH FINALLY STARTS TO LIFT NORTHEASTWARD INTO THE NORTHERN PLAINS LATER THURSDAY TAKING SURFACE LOW PRESSURE WITH IT ALONG...WHICH WILL IN TURN PUSH A COLD FRONT EASTWARD ACROSS THE AREA FRIDAY. THE ORIGINAL STATIONARY BOUNDARY MAY SETTLE SOUTHWARD INTO THE AREA AS THIS OCCURS SO CONVECTION WILL BE POSSIBLE ACROSS THE LOCAL AREA THURSDAY AND THURSDAY NIGHT...WITH THE COLD FRONT POTENTIALLY DRIVING CONVECTION FRIDAY MORNING. HOWEVER...THIS WILL BE ANOTHER SITUATION WHERE THE LARGER SCALE FORCING WILL BE WELL TO THE NORTHWEST AND THE FRONT WILL BE WEAKENING SO CONVECTIVE DEVELOPMENT MAY BE LIMITED. THE UPPER LOW MAY THEN MOVE EASTWARD BREAKING DOWN THE RIDGE INTO THE WEEKEND. OVERALL THE REST OF THE WEEK LOOKS POTENTIALLY ACTIVE BUT MUCH OF THE BETTER ORGANIZED CONVECTION WILL NEED TO BE BETTER IDENTIFIED AT A SHORTER TIME RANGE AS THE LOCATION OF KEY FEATURES WILL LARGELY DRIVE THE OUTCOME. WITH A MOIST UNSTABLE ATMOSPHERE IN PLACE LESS ORGANIZED CONVECTION WILL PROBABLY OCCUR AT TIMES. TEMPS LOOK TO MODERATE FROM WEDNESDAY ONWARD...WITH COOLER TEMPS MORE LIKELY INTO THE WEEKEND AS THE RIDGE BREAKS DOWN AND THE COOL FRONT PASSES. MDB && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 12Z... * POSSIBLE LAKE BREEZE TURNING WINDS EASTERLY MONDAY AFTERNOON. * CHANCES FOR TSRA MONDAY EVENING/NIGHT. BMD //DISCUSSION...UPDATED 12Z... MOST OF TODAY WILL BE VFR WITH MODEST SW/SSW WINDS. A FRONTAL BOUNDARY THAT PUSHED ACROSS THE AREA YESTERDAY NOW LIES ACROSS CENTRAL ILLINOIS AND MAY BE THE FOCUS FOR A FEW ISOLATED THUNDERSTORMS THIS AFTERNOON...HOWEVER THIS SHOULD REMAIN CONFINED TO AREAS SOUTH OF I-80. WINDS SHOULD GENERALLY BE OUT OF THE SOUTHWEST TO SOUTH-SOUTHWEST TODAY AT OR BELOW 10 KT THROUGH MID AFTERNOON. A LAKE BREEZE IS EXPECTED TO DEVELOP AND PUSH INLAND SEVERAL MILES INTO COOK COUNTY. FOR NOW ONLY THE HRRR WANTS TO PUSH THE BOUNDARY ALL THE WAY ACROSS BOTH ORD AND MDW TURNING WINDS TO THE EAST...WHILE MOST MODELS SHOW THE BOUNDARY STALLING IN THE VICINITY OF ORD AND SHY OF MDW. THE GRADIENT BEGINS TO INCREASE LATE AFTERNOON INTO THE EVENING SO EXPECT WINDS TO INCREASE AND SHOULD PUSH THE LAKE BREEZE BACK TOWARDS THE LAKE WITH SOUTHWEST FLOW RESUMING. THIS EVENING...A LOW LEVEL JET IS PROGGED TO DEVELOP AHEAD OF AN APPROACHING LOW KICKING OFF THUNDERSTORMS WHICH WILL INCREASE IN COVERAGE. MOST GLOBAL MODELS SHOW THE BULK OF THE ACTIVITY STAYING OVER WISCONSIN...HOWEVER THERE ARE HINTS THAT SOME OF THESE STORMS COULD PROPAGATE SOUTH INTO NORTHERN ILLINOIS IMPACTING THE TERMINALS LATE THIS EVENING AND OVERNIGHT. WILL MAINTAIN A PROB30 FOR NOW GIVEN THE LACK OF CERTAINTY IN THIS SCENARIO PANNING OUT. HI-RES GUIDANCE IS ALL OVER THE PLACE AND OFFERS LITTLE INSIGHT INTO HOW CONVECTION MIGHT EVOLVE THIS EVENING AND TONIGHT. BMD //ORD AND MDW CONFIDENCE...UPDATED 12Z... * HIGH CONFIDENCE IN PREVAILING VFR CONDITIONS AND SOUTHWEST WINDS TONIGHT THROUGH MIDDAY MONDAY. * LOW CONFIDENCE IN LAKE BREEZE PUSHING ACROSS TERMINALS MONDAY AFTERNOON. * HIGH CONFIDENCE IN THUNDERSTORMS DEVELOPING THIS EVENING ACROSS THE UPPER MIDWEST...LOW CONFIDENCE ON EXACT PLACEMENT. BMD //OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z... TUESDAY NIGHT THROUGH SUNDAY...PRIMARILY VFR WITH PERIODIC CHANCES FOR THUNDERSTORMS. BMD && .MARINE... 250 AM CDT AN ACTIVE PERIOD OF WEATHER IS EXPECTED ACROSS LAKE MICHIGAN FOR THE UPCOMING WEEK. TODAY...LOW PRESSURE WILL LIFT ACROSS ONTARIO LIFTING A WARM FRONT ACROSS LAKE MICHIGAN WITH SOUTH TO SOUTHWEST WINDS OVERSPREADING THE ENTIRE LAKE. AS THE LOW CONTINUES EAST TO THE MARITIME PROVINCES LATE TUESDAY...THE COLD FRONT WILL VERY SLOWLY SAG BACK SOUTH ACROSS LAKE MICHIGAN...THEN BEGIN TO SLOWLY LIFT BACK NORTH TOWARDS THE END OF THE WEEK AS ANOTHER LOW LIFTS ACROSS THE NORTHERN PLAINS. EACH DAY THERE WILL BE CHANCES FOR THUNDERSTORMS TO DEVELOP NEAR THE FRONT INCLUDING OVER PORTIONS OF LAKE MICHIGAN...AND SOME OF THESE STORMS COULD BECOME LARGER THUNDERSTORMS COMPLEXES THAT WILL CREATE A LOT OF VARIABILITY IN THE WIND FIELD. IN ADDITION...MID 60 AND EVEN 70 DEGREE DEWPOINTS LIFTING NORTH INTO THE REGION WILL LIKELY RESULT IN FOG FORMING OVER THE RELATIVELY COOLER WATERS OF LAKE MICHIGAN. BMD && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
403 AM CDT MON JUN 16 2014 .DISCUSSION... 308 AM CDT CONVECTIVE CHANCES WILL BE THE MAIN FORECAST CHALLENGE THROUGH THE REST OF THE WEEK AS UPPER LEVEL RIDGING DEVELOPS ACROSS THE MIDWEST AND GREAT LAKES. EARLY MORNING WATER VAPOR SHOWS A CLOSED UPPER LOW SPINNING NORTHWARD ACROSS WESTERN ONTARIO WITH AN ASSOCIATED SURFACE LOW FOLLOWING ALONG. A FRONTAL BOUNDARY ARCS EAST THEN SOUTH THEN SOUTHWEST FROM THE LOW ACROSS LOWER MICHIGAN AND INTO CENTRAL ILLINOIS. THE NEXT FEATURE OF INTEREST IS A LONGWAVE UPPER TROUGH SPREADING ACROSS THE WESTERN U.S. WITH SEVERAL EMBEDDED WAVES TRAVERSING THE SOUTHWESTERLY FLOW AROUND THE BASE AND TO ITS EAST. THIS WILL AID THE DEVELOPMENT OF LOW PRESSURE ACROSS THE PLAINS AND RESULT IN THE NORTHWARD MOVEMENT OF A FRONTAL BOUNDARY INTO THE UPPER MISSISSIPPI RIVER VALLEY INTO TONIGHT. THE LARGER SCALE TROUGH WILL TAKE ITS TIME MOVING ACROSS THE ROCKIES AND EVENTUALLY THE UPPER MIDWEST THROUGH THE REST OF THE WEEK. TODAY AND THIS EVENING...THE LONGWAVE UPPER TROUGH MOVING INTO THE WESTERN U.S. WILL MAKE SLOW PROGRESS TODAY BUT ENERGY WILL EJECT NORTHEASTWARD FROM ITS BASE AND HELP TO AMPLIFY UPPER RIDGING ACROSS THE CENTRAL U.S. THE COOL FRONTAL BOUNDARY TO THE SOUTH WILL MORE OR LESS WASH OUT AS SURFACE LOW PRESSURE ORGANIZES ACROSS THE NORTHERN HIGH PLAINS AND A WARM FRONT DEVELOPS TO ITS EAST. SOUTHWESTERLY FLOW WILL STRENGTHEN FROM THE SOUTHERN PLAINS TO THE WESTERN GREAT LAKES THROUGH THE DAY ALLOWING FOR STRONG WARM ADVECTION WHICH WILL RESULT IN H85 TEMPS INCREASING FROM AROUND +14 ACROSS THE LOCAL AREA THIS MORNING TO +18 OR BETTER BY TONIGHT. A VERY WARM DAY IS THEREFORE EXPECTED ACROSS THE AREA WITH HIGHS INTO THE UPPER 80S. AN INITIALLY WEAK PRESSURE GRADIENT WILL SUPPORT LIGHT WINDS THROUGH EARLY AFTERNOON ALLOWING A LAKE BREEZE TO SET UP WHICH WILL BRING SOME COOLING TO IMMEDIATE LAKE SHORE AREAS AND A BIT FURTHER INLAND ACROSS LAKE COUNTY ILLINOIS. DAYTIME HIGHS FOR THESE AREAS WILL LIKELY STILL BE QUITE WARM GIVEN THE WARM START TO THE DAY...BUT LATE AFTERNOON TEMPS WILL LIKELY CUT BACK INTO THE 70S IF NOT A BIT COOLER IN SPOTS. AN INFLUX OF BETTER MOISTURE WILL ARRIVE LATER TODAY AND CONTINUE INTO TONIGHT FROM THE SOUTHWEST. THEREFORE IT WILL BE INCREASINGLY HUMID THROUGH THE AFTERNOON AND MORE SO THIS EVENING. CHANCES FOR THUNDERSTORMS TODAY DO NOT LOOK GREAT BUT WATER VAPOR SHOWS SEVERAL SUBTLE WAVES MOVING NORTHEAST ACROSS OKLAHOMA/KANSAS WHICH WILL MOVE INTO THE SOUTHERN CWA LATE THIS AFTERNOON OR EARLY THIS EVENING. THIS...COMBINED WITH THE INFLUX OF BETTER THETA-E AIR AND WARM ASCENT ALREADY IN PLACE...AS WELL AS LITTLE IF ANY CAPPING BASED ON FORECAST SOUNDINGS...MAY SUPPORT ISOLATED/SCATTERED THUNDERSTORM DEVELOPMENT. GIVEN THE NUMBER OF LARGER SCALE FACTORS SUPPORTING CONVECTION WILL INCREASE THE AREA OF SLIGHT POPS ACROSS SOUTHERN/EASTERN AREAS LATE THIS AFTERNOON AND THIS EVENING. LATER TONIGHT AND TUESDAY...AS NOTED ABOVE...LOW PRESSURE WILL ORGANIZE ACROSS THE NORTHERN PLAINS AND PUSH A WARM FRONTAL BOUNDARY NORTHWARD ACROSS IOWA AND MINNESOTA AS UPPER LEVEL ENERGY PUSHES ACROSS THAT AREA. SEVERE THUNDERSTORMS ARE EXPECTED TO DEVELOP ACROSS SOUTH DAKOTA/IOWA/MINNESOTA THIS AFTERNOON AND ORGANIZE INTO AN MCS BY EVENING AS THE LOW LEVEL JET DEVELOPS ACROSS IOWA AND INTO FAR SOUTHERN MINNESOTA. THE LOW LEVEL JET WILL SHIFT MORE SOUTHWESTERLY INTO THE OVERNIGHT BRINGING A STEADY FEED OF MOISTURE INTO NORTHERN ILLINOIS AND CENTRAL/SOUTHERN WISCONSIN. 850-300 MB THICKNESS RIDGE STRETCHES FROM SOUTHWEST IOWA TO WESTERN LAKE SUPERIOR OVERNIGHT RESULTING IN A NORTHWEST TO SOUTHWEST ORIENTATION OF THE THICKNESS GRADIENT ACROSS MUCH OF WISCONSIN AND ILLINOIS. THIS AND THE SHIFTING OF THE LOW LEVEL JET TO A MORE SOUTHWESTERLY ORIENTATION SHIFTING THE BETTER MOISTURE TRANSPORT SUPPORT AN OVERALL EAST TO SOUTHEAST MOVEMENT OF WHATEVER MCS RESULTS FROM THE AFTERNOON/EVENING CONVECTION. THIS MAY BE MANIFESTED AS MORE OF A SOUTHWARD DEVELOPMENT VS. STORM MOTION GIVEN THAT BETTER MOISTURE WILL BE TO THE SOUTH AND THE INSTABILITY GRADIENT IS EXPECTED TO BE ORIENTED FROM NORTHWEST TO SOUTHEAST ACROSS CENTRAL/SOUTHERN WISCONSIN. IN ADDITION...BACKWARD PROPAGATING CORFIDI VECTORS SUPPORT THIS SOUTHWARD EXPANSION IDEA. HIGH RES GUIDANCE SHOWS A MYRIAD OF SOLUTIONS SO AT THIS TIME RANGE PREFER TO LEAN MORE HEAVILY ON THE LARGER SCALE ELEMENTS AND CONCEPTUAL MODELS. THIS THINKING SUPPORTS MUCH OF THE CONVECTION BEING ACROSS WISCONSIN BUT SEE ENOUGH SUPPORT FOR SOME SORT OF A SOUTHWARD EXPANSION/PROPAGATION OVERNIGHT WITH ANOTHER QUESTION BEING HOW FAR SOUTH AS WELL AS TIMING. WILL TWEAK POPS FOR TONIGHT AND TUESDAY MORNING TO SHOW A SLIGHTLY GREATER COVERAGE OF POPS GENERALLY ALONG AND NORTH OF I-80. HEAVY RAIN AND EVEN SOME DAMAGING WIND GUSTS WOULD BE THE MAIN THREATS. THE UPPER RIDGING WILL BECOME BETTER ESTABLISHED TUESDAY. WHATEVER CONVECTION IS AROUND IN THE MORNING WILL LIKELY END AND IT APPEARS THAT THE REST OF TUESDAY MAY BE DRY WITH THE FOCUS FOR CONVECTION TO THE NORTH. HOWEVER...THIS MAY ALSO BE DEPENDENT ON WHAT PLAYS OUT TUESDAY MORNING IN TERMS OF LEFTOVER BOUNDARIES ETC. THAT MAY BE ABLE TO TRIGGER ISOLD/SCATTERED CONVECTION LATER TUESDAY AS WE WILL STILL BE UNSTABLE. UPSTREAM CONVECTION ACROSS MN/IA/WI LATER TUESDAY MAY BE ABLE TO WORK ITS WAY INTO THE NORTHERN CWA AGAIN TUESDAY NIGHT...WITH HEAVY RAIN AND DAMAGING WIND POTENTIAL. OTHERWISE A STRONGER SOUTHWESTERLY FLOW WILL BE IN PLACE AS LOW PRESSURE REMAINS ACROSS THE NORTHERN PLAINS SO A LAKE BREEZE LOOKS UNLIKELY SO EVEN LAKESHORE AREAS SHOULD WARM INTO THE 80...WITH HIGHS NEAR 90 ELSEWHERE WITH A RATHER STICKY AIRMASS IN PLACE. WEDNESDAY AND BEYOND...SURFACE LOW PRESSURE WILL CONTINUE TO BE POSITIONED ACROSS THE CENTRAL AND NORTHERN PLAINS WITH A STATIONARY FRONT STRETCHING EASTWARD ACROSS CENTRAL OR SOUTHERN WISCONSIN. THE LONGWAVE UPPER TROUGH WILL STILL BE TO THE WEST AS WELL SO IMPULSES ARE LIKELY TO EMANATE NORTHEASTWARD UP THE RIDGE OVER THE UPPER MIDWEST/WESTERN GREAT LAKES. THE POSITION OF THE FRONT WILL LIKELY DRIVE WHERE THE CONVECTION WILL BE FOCUSED WEDNESDAY BUT LESS ORGANIZED CONVECTION MAY OCCUR ACROSS A LARGER AREA...ESPECIALLY IN CONJUNCTION WITH ANY SUBTLE UPPER WAVES. THE UPPER TROUGH FINALLY STARTS TO LIFT NORTHEASTWARD INTO THE NORTHERN PLAINS LATER THURSDAY TAKING SURFACE LOW PRESSURE WITH IT ALONG...WHICH WILL IN TURN PUSH A COLD FRONT EASTWARD ACROSS THE AREA FRIDAY. THE ORIGINAL STATIONARY BOUNDARY MAY SETTLE SOUTHWARD INTO THE AREA AS THIS OCCURS SO CONVECTION WILL BE POSSIBLE ACROSS THE LOCAL AREA THURSDAY AND THURSDAY NIGHT...WITH THE COLD FRONT POTENTIALLY DRIVING CONVECTION FRIDAY MORNING. HOWEVER...THIS WILL BE ANOTHER SITUATION WHERE THE LARGER SCALE FORCING WILL BE WELL TO THE NORTHWEST AND THE FRONT WILL BE WEAKENING SO CONVECTIVE DEVELOPMENT MAY BE LIMITED. THE UPPER LOW MAY THEN MOVE EASTWARD BREAKING DOWN THE RIDGE INTO THE WEEKEND. OVERALL THE REST OF THE WEEK LOOKS POTENTIALLY ACTIVE BUT MUCH OF THE BETTER ORGANIZED CONVECTION WILL NEED TO BE BETTER IDENTIFIED AT A SHORTER TIME RANGE AS THE LOCATION OF KEY FEATURES WILL LARGELY DRIVE THE OUTCOME. WITH A MOIST UNSTABLE ATMOSPHERE IN PLACE LESS ORGANIZED CONVECTION WILL PROBABLY OCCUR AT TIMES. TEMPS LOOK TO MODERATE FROM WEDNESDAY ONWARD...WITH COOLER TEMPS MORE LIKELY INTO THE WEEKEND AS THE RIDGE BREAKS DOWN AND THE COOL FRONT PASSES. MDB && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 09Z... * POSSIBLE LAKE BREEZE TURNING WINDS EASTERLY MONDAY AFTERNOON. * CHANCES FOR TSRA MONDAY EVENING/NIGHT. BMD //DISCUSSION...UPDATED 06Z... WEAK RIDGING WILL BUILD ACROSS THE AREA TONIGHT WITH A LIGHT SOUTHWEST WIND AND VFR CONDITIONS EXPECTED TO PREVAIL. WINDS WILL BE MARGINAL FOR A LAKE BREEZE TO DEVELOP MONDAY AFTERNOON. HIGH RES GUIDANCE DOES SHOW THE BOUNDARY PUSHING INLAND TO NEAR ORD/MDW...BUT THE GRADIENT IS PROGGED TO INCREASE THROUGH THE EVENING WITH SOUTHWEST WINDS PICKING BACK UP. THIS SHOULD PUSH THE LAKE BREEZE BACK TOWARDS THE LAKE FRONT...AND IT MAY NOT EVEN MAKE THE TERMINALS AT ALL. THE FRONTAL BOUNDARY WHICH HAS MOVED SOUTH OF THE TERMINALS TODAY WILL MIX BACK NORTH OF THE AREA MONDAY. MODELS CONTINUE TO ADVERTISE A SIGNIFICANT CONVECTIVE COMPLEX FORMING MONDAY EVENING/NIGHT NEAR THE FRONT. MODERATE INSTABILITY DOES DEVELOP LOCALLY AND IT IS FEASIBLE THAT ANY OUTFLOW THAT SINKS SOUTH FROM THE THUNDERSTORMS OVER WISCONSIN COULD KICK OFF SCATTERED THUNDERSTORMS CLOSE TO THE TERMINALS TOMORROW EVENING. WILL ADD A PROB30 FOR TSRA FOR NOW. CONFIDENCE IN THE DEVELOPMENT OF THE COMPLEX IS MEDIUM TO HIGH...BUT SPECIFICS ON THE EVOLUTION AND THE SOUTHWARD EXTENT ARE LOWER. BMD //ORD AND MDW CONFIDENCE...UPDATED 09Z... * HIGH CONFIDENCE IN PREVAILING VFR CONDITIONS AND SOUTHWEST WINDS TONIGHT THROUGH MIDDAY MONDAY. * LOW CONFIDENCE IN LAKE BREEZE PUSHING ACROSS TERMINALS MONDAY AFTERNOON. * HIGH CONFIDENCE IN TSRA NORTH OF THE TERMINALS...LOW-MEDIUM CONFIDENCE IT WILL DEVELOP SOUTH TO THE TERMINALS. BMD //OUTLOOK FOR ORD/MDW FOR 12Z TUESDAY-12Z SUNDAY...UPDATED 00Z... TUESDAY...CHANCE OF EARLY MORNING TSRA AND THEN A CHANCE AGAIN LATE IN THE DAY INTO TUESDAY NIGHT. WEDNESDAY-SATURDAY...CHANCES OF PERIODIC TSRA. && .MARINE... 250 AM CDT AN ACTIVE PERIOD OF WEATHER IS EXPECTED ACROSS LAKE MICHIGAN FOR THE UPCOMING WEEK. TODAY...LOW PRESSURE WILL LIFT ACROSS ONTARIO LIFTING A WARM FRONT ACROSS LAKE MICHIGAN WITH SOUTH TO SOUTHWEST WINDS OVERSPREADING THE ENTIRE LAKE. AS THE LOW CONTINUES EAST TO THE MARITIME PROVINCES LATE TUESDAY...THE COLD FRONT WILL VERY SLOWLY SAG BACK SOUTH ACROSS LAKE MICHIGAN...THEN BEGIN TO SLOWLY LIFT BACK NORTH TOWARDS THE END OF THE WEEK AS ANOTHER LOW LIFTS ACROSS THE NORTHERN PLAINS. EACH DAY THERE WILL BE CHANCES FOR THUNDERSTORMS TO DEVELOP NEAR THE FRONT INCLUDING OVER PORTIONS OF LAKE MICHIGAN...AND SOME OF THESE STORMS COULD BECOME LARGER THUNDERSTORMS COMPLEXES THAT WILL CREATE A LOT OF VARIABILITY IN THE WIND FIELD. IN ADDITION...MID 60 AND EVEN 70 DEGREE DEWPOINTS LIFTING NORTH INTO THE REGION WILL LIKELY RESULT IN FOG FORMING OVER THE RELATIVELY COOLER WATERS OF LAKE MICHIGAN. BMD && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion National Weather Service Lincoln IL 330 AM CDT Mon Jun 16 2014 .DISCUSSION... ISSUED 330 AM CDT Mon Jun 16 2014 SHORT TERM...Today through Wednesday night Summer weather to prevail this week as temperatures warm into the upper 80s and lower 90s through Thu with moist dewpoints in the upper 60s and lower 70s. 00Z models have trended further north with convection chances through Wed with strong upper level ridge building across the eastern states into Wed. Radar mosaic shows isolated showers and thunderstorms developing past few hours south of I-72 with weakening front moving se into central IL and short wave to push east into central/southern IN during the morning. Airmass is unstable today especially this afternoon and feel this to support more redevelopment of isolated convection from I-72 south. HRRR and RAP suggests this redevelopment this afternoon over central and southern counties. Highs in the upper 80s to near 90F and humid dewpoints in the upper 60s to lower 70s. Convection chances then shift into IA/WI and northern IL tonight through Wed with stronger focus of low level jet and closer to upper level lows over northern tier states. SPC has slight risk nw of Knox and Stark counties tonight and keeps slight risk north of I-88 on Tue & Tue night. Carried just slight chance of convection over areas north of Peoria tonight through Wed morning. Then increase convection chances Wed afternoon and Wed night and especially Thu into Fri with strong upper level low moving into the northern plains and upper MS river valley and pushing a front back south late this week. SPC has slight risk of severe storms late Wed afternoon and Wed night north of Peoria over Knox, Stark and Marshall counties. Highs in the upper 80s and lower 90s through Thu and then starts cooling off a bit late this week and into the weekend. LONG TERM...Thursday through Sunday Stayed close to Allblend for weather from Thu through Sunday with daily chances of showers and thunderstorms, though perhaps a break around Sat night. Highs still in the 80s this weekend and then cooler on Monday. 07 && .AVIATION... ISSUED 1115 PM CDT Sun Jun 15 2014 Not much change from previous thinking with the main concerns this period mainly revolving around the potential for low VFR cigs later tonight into Monday morning, possibly lowering briefly to MVFR. VAD wind profiles indicating winds gradually backing more into a southerly direction, especially over Missouri which should help to bring the lower VFR cloud deck, currently over Mo, northeast into our area by morning. The threat for some MVFR fog in the 09z-13z time frame is still there as temp/dew point spreads decrease overnight. Forecast soundings continue to show cumulus development by late morning with cloud bases in the 3500-4500 foot range. Light south to southwest winds tonight will be more southerly on Monday with speeds of 10 to 15 kts. Smith && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
141 PM EDT MON JUN 16 2014 .UPDATE... THE LONG TERM SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 209 AM EDT MON JUN 16 2014 SUMMER WEATHER IS IN STORE THIS WEEK AS A BERMUDA HIGH WILL CONTINUE TO PUSH WARMER AND MORE HUMID AIR INTO THE OHIO VALLEY ON SOUTHERLY WINDS. A LINGERING FRONTAL BOUNDARY OVER CENTRAL INDIANA WILL BRING A FEW SCATTERED STORMS TODAY...HOWEVER AS THE WEEK PROGRESSES A RIDGE OF HIGH PRESSURE IS EXPECTED TO BUILD ALOFT AND ALLOW HOT SUMMER WEATHER BUILD ACROSS REGION. TEMPERATURES SHOULD REACH THE 90S FOR THE FIRST TIME IN 2014. CHANCES FOR THUNDERSTORMS WILL BECOME MORE NUMEROUS DURING THE SECOND HALF OF THE WEEK. && .NEAR TERM /REST OF TODAY/... ISSUED AT 951 AM EDT MON JUN 16 2014 SCATTERED CONVECTION IMPACTING THE FORECAST AREA THIS MORNING...ARCING ROUGHLY FROM THE SOUTHERN INDY METRO BACK TO THE SOUTHWEST INTO THE LOWER WABASH VALLEY AND BACK INTO SOUTH CENTRAL ILLINOIS. TEMPS WERE GENERALLY IN THE 70S AT 1330Z...WARMER WHERE RAIN WAS NOT OR HAD NOT FALLEN. CURRENT CONVECTIVE SETUP REQUIRING SOME CHANGES TO THE MORNING FORECAST. PRESENCE OF THE WEAK BOUNDARY AND A WAVE ALOFT CONTRIBUTING TO THE STORMS THIS MORNING. MESOANALYSIS INDICATING AN AXIS OF 1000-1500 J/KG MLCAPES ACROSS THE FORECAST AREA WITH 850MB WINDS AT AROUND 25KTS CONTRIBUTING TO CONVECTION AS WELL. WEAK UPPER WAVE WILL SHIFT EAST INTO THE EARLY AFTERNOON AS THE RIDGE ALOFT BEGINS TO EXPAND NORTH INTO THE REGION. COMBINED WITH A PROGRESSIVE WEAKENING OF BOUNDARY LAYER FLOW...EXPECT CONVECTIVE COVERAGE TO DIMINISH INTO THE AFTERNOON HOURS. WILL NEED TO MONITOR PROGRESSION OF STORMS IN SOUTH-CENTRAL ILLINOIS...AS CURRENT EXTRAPOLATION WOULD BRING THESE CELLS INTO THE LOWER WABASH VALLEY OVER THE NEXT FEW HOURS. CURRENT HRRR BRINGS THIS ACTIVITY INTO SOUTHWEST COUNTIES IN VICINITY OF THE REMNANT BOUNDARY BEFORE WEAKENING STORMS AS THE AFTERNOON PROGRESSES AND REFOCUSING MORE EXTENSIVE CONVECTION BACK TO THE WEST OVER THE MID MISSISSIPPI VALLEY. WILL MAINTAIN AN ISOLATED MENTION FOR STORMS THROUGH LATE AFTERNOON TO ACCOUNT FOR ANY CELLS THAT CAN GET GOING IN THE VICINITY OF THE BOUNDARY BUT OVERALL...AFTERNOON SHOULD BE DRIER THAN THIS MORNING HAS IN MOST AREAS. LOWERED HIGH TEMPS IN THE SOUTH A COUPLE DEGREES WITH CLOUDS/PRECIP THIS MORNING LIMITING TEMP RISES A BIT. EXPECT A STEAMY AFTERNOON...ESPECIALLY IN AREAS THAT RECEIVED RAIN THIS MORNING. ZONE AND GRID UPDATES OUT. && .SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/... ISSUED AT 209 AM EDT MON JUN 16 2014 MODELS SEEM TO HAVE A BIT BETTER IDEA ON THE PATTERN ALOFT THROUGH MID WEEK WHICH SHOULD ALLOW US TO REMOVE POPS THROUGH WEDNESDAY NIGHT. GFS AND NAM BOTH ALLOW A LOW ALOFT TO DIG OVER THE WESTERN UNITED STATES THROUGH WEDNESDAY. THE RESPONSE ACROSS THE EASTERN HALF OF THE COUNTRY IS A STRONG RIDGE OVER THE OHIO VALLEY WHICH WILL KEEP ANY PASSING SHORT WAVES WELL NORTH OF INDIANA. THE PATTERN WILL ALSO ALLOW SOME OF THE WARMEST TEMPERATURES OF THE YEAR SO FAR TO BUILD ACROSS CENTRAL INDIANA. FORECAST SOUNDINGS TONIGHT THROUGH WEDNESDAY SHOW 700MB TEMPS SURGING ABOVE 10C...EFFECTIVELY CAPPING THE COLUMN. FURTHERMORE CONVECTIVE TEMPERATURES REACH UNATTAINABLE LEVELS IN THE UPPER 90S AND LOW 100S. LARGE HIGH PRESSURE AT THE SURFACE CENTERED OVER THE SOUTHEASTERN STATES WILL KEEP ITS INFLUENCE OVER INDIANA AS WELL. ALL OF THIS WILL RESULT IN HOT...MOSTLY SUNNY DAYS AND WARM CLEAR NIGHTS. WILL USE A BLEND ON HIGH TEMPERATURES...WHICH WILL RESULT IN OUR FIRST 90S OF THE YEAR ON TUESDAY. WILL TREND LOWS AT OR ABOVE MAVMOS. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... ISSUED AT 141 PM EDT MON JUN 16 2014 THUNDERSTORM CHANCES ALONG WITH TEMPERATURES WILL BE THE MAIN FOCUS REGARDING THE LONG TERM FORECAST. THE MODELS ARE IN GENERAL AGREEMENT WITH MEAN UPPER RIDGING ACROSS THE CONTINENTAL UNITED STATES WITH TWIN UPPER LOWS ACROSS THE NORTHEASTERN UNITED STATES AND CANADIAN MARITIMES AS WELL AS OFF THE PACIFIC NORTHWEST COAST. HOWEVER...THE EXTENDED MODELS HAVE TIMING ISSUES REGARDING ANOTHER UPPER LOW ACROSS THE NORTHERN PLAINS. ALL MODELS EVENTUALLY OPEN UP THIS FEATURE AND PIVOT IT SOUTHEAST ACROSS THE LOWER GREAT LAKES AND OHIO VALLEY. HOWEVER...THE 00Z OPERATIONAL ECMWF IS MUCH QUICKER TO DO SO BRINGING THIS FEATURE ACROSS THE AREA SATURDAY NIGHT AND SUNDAY MORNING WHEREAS THE 12Z GFS HOLDS OFF UNTIL MONDAY BRINGING THE TROUGH THROUGH. THE 00Z ECMWF HAS BEEN LESS CONSISTENT AND ITS 00Z RUN WOULD SUGGEST A QUICKER END TO ANY THUNDERSTORM ACTIVITY. WITH MODEL UNCERTAINTY...WILL STICK WITH PERSISTENCE AND THE REGIONAL ALLBLEND AND KEEP THUNDERSTORM CHANCES AROUND THROUGH THE ENTIRE EXTENDED AND NOT MESS WITH TEMPERATURES. && .AVIATION /DISCUSSION FOR 161800Z TAF ISSUANCE/... ISSUED AT 1237 PM EDT SUN JUN 16 2014 CAN NOT RULE OUT ADDITIONAL THUNDERSTORMS THIS AFTERNOON BUT RADAR TRENDS AND CONVECTIVE ALLOWING MODELS SUGGEST ANY ACTIVITY WILL BE TOO ISOLATED TO PUT IN ANY OF THE TAF SITES. OTHERWISE...GOOD CONFIDENCE THAT VFR CONDITIONS WILL DOMINATE THROUGH TUESDAY. WOULD NOT RULE OUT BRIEF FOG ESPECIALLY AT BMG WHERE OVER A HALF AN INCH OF RAIN FELL THIS MORNING. STILL...TOO FAR OUT AND CONFIDENCE NOT HIGH ENOUGH THAT ANY WILL DEVELOP WITH SOUTH WINDS STAYING UP NEAR 5 KNOTS. SURFACE PRESSURE GRADIENT WILL TIGHTEN A BIT TOMORROW ALLOWING FOR SOUTHWEST WINDS TO AROUND 15 KNOTS AND GUSTS TO 20 KNOTS OR MORE AFTER 16Z. && .IND WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SYNOPSIS...PUMA/RYAN NEAR TERM...RYAN SHORT TERM...PUMA LONG TERM....MK AVIATION...MK VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON TWITTER AND YOUTUBE AT: WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1237 PM EDT MON JUN 16 2014 .UPDATE... THE AVIATION SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 209 AM EDT MON JUN 16 2014 SUMMER WEATHER IS IN STORE THIS WEEK AS A BERMUDA HIGH WILL CONTINUE TO PUSH WARMER AND MORE HUMID AIR INTO THE OHIO VALLEY ON SOUTHERLY WINDS. A LINGERING FRONTAL BOUNDARY OVER CENTRAL INDIANA WILL BRING A FEW SCATTERED STORMS TODAY...HOWEVER AS THE WEEK PROGRESSES A RIDGE OF HIGH PRESSURE IS EXPECTED TO BUILD ALOFT AND ALLOW HOT SUMMER WEATHER BUILD ACROSS REGION. TEMPERATURES SHOULD REACH THE 90S FOR THE FIRST TIME IN 2014. CHANCES FOR THUNDERSTORMS WILL BECOME MORE NUMEROUS DURING THE SECOND HALF OF THE WEEK. && .NEAR TERM /REST OF TODAY/... ISSUED AT 951 AM EDT MON JUN 16 2014 SCATTERED CONVECTION IMPACTING THE FORECAST AREA THIS MORNING...ARCING ROUGHLY FROM THE SOUTHERN INDY METRO BACK TO THE SOUTHWEST INTO THE LOWER WABASH VALLEY AND BACK INTO SOUTH CENTRAL ILLINOIS. TEMPS WERE GENERALLY IN THE 70S AT 1330Z...WARMER WHERE RAIN WAS NOT OR HAD NOT FALLEN. CURRENT CONVECTIVE SETUP REQUIRING SOME CHANGES TO THE MORNING FORECAST. PRESENCE OF THE WEAK BOUNDARY AND A WAVE ALOFT CONTRIBUTING TO THE STORMS THIS MORNING. MESOANALYSIS INDICATING AN AXIS OF 1000-1500 J/KG MLCAPES ACROSS THE FORECAST AREA WITH 850MB WINDS AT AROUND 25KTS CONTRIBUTING TO CONVECTION AS WELL. WEAK UPPER WAVE WILL SHIFT EAST INTO THE EARLY AFTERNOON AS THE RIDGE ALOFT BEGINS TO EXPAND NORTH INTO THE REGION. COMBINED WITH A PROGRESSIVE WEAKENING OF BOUNDARY LAYER FLOW...EXPECT CONVECTIVE COVERAGE TO DIMINISH INTO THE AFTERNOON HOURS. WILL NEED TO MONITOR PROGRESSION OF STORMS IN SOUTH-CENTRAL ILLINOIS...AS CURRENT EXTRAPOLATION WOULD BRING THESE CELLS INTO THE LOWER WABASH VALLEY OVER THE NEXT FEW HOURS. CURRENT HRRR BRINGS THIS ACTIVITY INTO SOUTHWEST COUNTIES IN VICINITY OF THE REMNANT BOUNDARY BEFORE WEAKENING STORMS AS THE AFTERNOON PROGRESSES AND REFOCUSING MORE EXTENSIVE CONVECTION BACK TO THE WEST OVER THE MID MISSISSIPPI VALLEY. WILL MAINTAIN AN ISOLATED MENTION FOR STORMS THROUGH LATE AFTERNOON TO ACCOUNT FOR ANY CELLS THAT CAN GET GOING IN THE VICINITY OF THE BOUNDARY BUT OVERALL...AFTERNOON SHOULD BE DRIER THAN THIS MORNING HAS IN MOST AREAS. LOWERED HIGH TEMPS IN THE SOUTH A COUPLE DEGREES WITH CLOUDS/PRECIP THIS MORNING LIMITING TEMP RISES A BIT. EXPECT A STEAMY AFTERNOON...ESPECIALLY IN AREAS THAT RECEIVED RAIN THIS MORNING. ZONE AND GRID UPDATES OUT. && .SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/... ISSUED AT 209 AM EDT MON JUN 16 2014 MODELS SEEM TO HAVE A BIT BETTER IDEA ON THE PATTERN ALOFT THROUGH MID WEEK WHICH SHOULD ALLOW US TO REMOVE POPS THROUGH WEDNESDAY NIGHT. GFS AND NAM BOTH ALLOW A LOW ALOFT TO DIG OVER THE WESTERN UNITED STATES THROUGH WEDNESDAY. THE RESPONSE ACROSS THE EASTERN HALF OF THE COUNTRY IS A STRONG RIDGE OVER THE OHIO VALLEY WHICH WILL KEEP ANY PASSING SHORT WAVES WELL NORTH OF INDIANA. THE PATTERN WILL ALSO ALLOW SOME OF THE WARMEST TEMPERATURES OF THE YEAR SO FAR TO BUILD ACROSS CENTRAL INDIANA. FORECAST SOUNDINGS TONIGHT THROUGH WEDNESDAY SHOW 700MB TEMPS SURGING ABOVE 10C...EFFECTIVELY CAPPING THE COLUMN. FURTHERMORE CONVECTIVE TEMPERATURES REACH UNATTAINABLE LEVELS IN THE UPPER 90S AND LOW 100S. LARGE HIGH PRESSURE AT THE SURFACE CENTERED OVER THE SOUTHEASTERN STATES WILL KEEP ITS INFLUENCE OVER INDIANA AS WELL. ALL OF THIS WILL RESULT IN HOT...MOSTLY SUNNY DAYS AND WARM CLEAR NIGHTS. WILL USE A BLEND ON HIGH TEMPERATURES...WHICH WILL RESULT IN OUR FIRST 90S OF THE YEAR ON TUESDAY. WILL TREND LOWS AT OR ABOVE MAVMOS. && .LONG TERM /THURSDAY THROUGH SUNDAY/... ISSUED AT 225 AM EDT MON JUN 16 2014 MODELS ARE CLOSE ENOUGH THAT THE ALLBLEND INITIALIZATION WAS ACCEPTED FOR MOST ITEMS. AN UPPER RIDGE WILL BREAK DOWN EARLY IN THE LONG TERM ALLOWING AN UPPER LOW TO INFLUENCE THE WEATHER INTO THE WEEKEND. MODELS STILL DIFFER SOME ON EXACT PATH OF UPPER LOW...BUT IT WILL BE CLOSE ENOUGH FOR CHANCES FOR RAIN ACROSS THE AREA. DID KNOCK ALLBLEND/S LIKELY POPS BACK DOWN TO CHANCE CATEGORY DUE TO THE AFOREMENTIONED UNCERTAINTY. OTHERWISE CHANCE POPS WILL BE THE RULE THROUGH THE EXTENDED. TEMPERATURES WILL GRADUALLY COOL FROM THE UPPER 80S EARLY IN THE PERIOD TO THE LOWER AND MIDDLE 80S BY SUNDAY AS THE UPPER LOW HAS MORE OF AN INFLUENCE. && .AVIATION /DISCUSSION FOR 161800Z TAF ISSUANCE/... ISSUED AT 1237 PM EDT SUN JUN 16 2014 CAN NOT RULE OUT ADDITIONAL THUNDERSTORMS THIS AFTERNOON BUT RADAR TRENDS AND CONVECTIVE ALLOWING MODELS SUGGEST ANY ACTIVITY WILL BE TOO ISOLATED TO PUT IN ANY OF THE TAF SITES. OTHERWISE...GOOD CONFIDENCE THAT VFR CONDITIONS WILL DOMINATE THROUGH TUESDAY. WOULD NOT RULE OUT BRIEF FOG ESPECIALLY AT BMG WHERE OVER A HALF AN INCH OF RAIN FELL THIS MORNING. STILL...TOO FAR OUT AND CONFIDENCE NOT HIGH ENOUGH THAT ANY WILL DEVELOP WITH SOUTH WINDS STAYING UP NEAR 5 KNOTS. SURFACE PRESSURE GRADIENT WILL TIGHTEN A BIT TOMORROW ALLOWING FOR SOUTHWEST WINDS TO AROUND 15 KNOTS AND GUSTS TO 20 KNOTS OR MORE AFTER 16Z. && .IND WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SYNOPSIS...PUMA/RYAN NEAR TERM...RYAN SHORT TERM...PUMA LONG TERM....50 AVIATION...MK VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON TWITTER AND YOUTUBE AT: WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1022 AM EDT MON JUN 16 2014 .UPDATE... THE AVIATION SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 209 AM EDT MON JUN 16 2014 SUMMER WEATHER IS IN STORE THIS WEEK AS A BERMUDA HIGH WILL CONTINUE TO PUSH WARMER AND MORE HUMID AIR INTO THE OHIO VALLEY ON SOUTHERLY WINDS. A LINGERING FRONTAL BOUNDARY OVER CENTRAL INDIANA WILL BRING A FEW SCATTERED STORMS TODAY...HOWEVER AS THE WEEK PROGRESSES A RIDGE OF HIGH PRESSURE IS EXPECTED TO BUILD ALOFT AND ALLOW HOT SUMMER WEATHER BUILD ACROSS REGION. TEMPERATURES SHOULD REACH THE 90S FOR THE FIRST TIME IN 2014. CHANCES FOR THUNDERSTORMS WILL BECOME MORE NUMEROUS DURING THE SECOND HALF OF THE WEEK. && .NEAR TERM /REST OF TODAY/... ISSUED AT 951 AM EDT MON JUN 16 2014 SCATTERED CONVECTION IMPACTING THE FORECAST AREA THIS MORNING...ARCING ROUGHLY FROM THE SOUTHERN INDY METRO BACK TO THE SOUTHWEST INTO THE LOWER WABASH VALLEY AND BACK INTO SOUTH CENTRAL ILLINOIS. TEMPS WERE GENERALLY IN THE 70S AT 1330Z...WARMER WHERE RAIN WAS NOT OR HAD NOT FALLEN. CURRENT CONVECTIVE SETUP REQUIRING SOME CHANGES TO THE MORNING FORECAST. PRESENCE OF THE WEAK BOUNDARY AND A WAVE ALOFT CONTRIBUTING TO THE STORMS THIS MORNING. MESOANALYSIS INDICATING AN AXIS OF 1000-1500 J/KG MLCAPES ACROSS THE FORECAST AREA WITH 850MB WINDS AT AROUND 25KTS CONTRIBUTING TO CONVECTION AS WELL. WEAK UPPER WAVE WILL SHIFT EAST INTO THE EARLY AFTERNOON AS THE RIDGE ALOFT BEGINS TO EXPAND NORTH INTO THE REGION. COMBINED WITH A PROGRESSIVE WEAKENING OF BOUNDARY LAYER FLOW...EXPECT CONVECTIVE COVERAGE TO DIMINISH INTO THE AFTERNOON HOURS. WILL NEED TO MONITOR PROGRESSION OF STORMS IN SOUTH-CENTRAL ILLINOIS...AS CURRENT EXTRAPOLATION WOULD BRING THESE CELLS INTO THE LOWER WABASH VALLEY OVER THE NEXT FEW HOURS. CURRENT HRRR BRINGS THIS ACTIVITY INTO SOUTHWEST COUNTIES IN VICINITY OF THE REMNANT BOUNDARY BEFORE WEAKENING STORMS AS THE AFTERNOON PROGRESSES AND REFOCUSING MORE EXTENSIVE CONVECTION BACK TO THE WEST OVER THE MID MISSISSIPPI VALLEY. WILL MAINTAIN AN ISOLATED MENTION FOR STORMS THROUGH LATE AFTERNOON TO ACCOUNT FOR ANY CELLS THAT CAN GET GOING IN THE VICINITY OF THE BOUNDARY BUT OVERALL...AFTERNOON SHOULD BE DRIER THAN THIS MORNING HAS IN MOST AREAS. LOWERED HIGH TEMPS IN THE SOUTH A COUPLE DEGREES WITH CLOUDS/PRECIP THIS MORNING LIMITING TEMP RISES A BIT. EXPECT A STEAMY AFTERNOON...ESPECIALLY IN AREAS THAT RECEIVED RAIN THIS MORNING. ZONE AND GRID UPDATES OUT. && .SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/... ISSUED AT 209 AM EDT MON JUN 16 2014 MODELS SEEM TO HAVE A BIT BETTER IDEA ON THE PATTERN ALOFT THROUGH MID WEEK WHICH SHOULD ALLOW US TO REMOVE POPS THROUGH WEDNESDAY NIGHT. GFS AND NAM BOTH ALLOW A LOW ALOFT TO DIG OVER THE WESTERN UNITED STATES THROUGH WEDNESDAY. THE RESPONSE ACROSS THE EASTERN HALF OF THE COUNTRY IS A STRONG RIDGE OVER THE OHIO VALLEY WHICH WILL KEEP ANY PASSING SHORT WAVES WELL NORTH OF INDIANA. THE PATTERN WILL ALSO ALLOW SOME OF THE WARMEST TEMPERATURES OF THE YEAR SO FAR TO BUILD ACROSS CENTRAL INDIANA. FORECAST SOUNDINGS TONIGHT THROUGH WEDNESDAY SHOW 700MB TEMPS SURGING ABOVE 10C...EFFECTIVELY CAPPING THE COLUMN. FURTHERMORE CONVECTIVE TEMPERATURES REACH UNATTAINABLE LEVELS IN THE UPPER 90S AND LOW 100S. LARGE HIGH PRESSURE AT THE SURFACE CENTERED OVER THE SOUTHEASTERN STATES WILL KEEP ITS INFLUENCE OVER INDIANA AS WELL. ALL OF THIS WILL RESULT IN HOT...MOSTLY SUNNY DAYS AND WARM CLEAR NIGHTS. WILL USE A BLEND ON HIGH TEMPERATURES...WHICH WILL RESULT IN OUR FIRST 90S OF THE YEAR ON TUESDAY. WILL TREND LOWS AT OR ABOVE MAVMOS. && .LONG TERM /THURSDAY THROUGH SUNDAY/... ISSUED AT 225 AM EDT MON JUN 16 2014 MODELS ARE CLOSE ENOUGH THAT THE ALLBLEND INITIALIZATION WAS ACCEPTED FOR MOST ITEMS. AN UPPER RIDGE WILL BREAK DOWN EARLY IN THE LONG TERM ALLOWING AN UPPER LOW TO INFLUENCE THE WEATHER INTO THE WEEKEND. MODELS STILL DIFFER SOME ON EXACT PATH OF UPPER LOW...BUT IT WILL BE CLOSE ENOUGH FOR CHANCES FOR RAIN ACROSS THE AREA. DID KNOCK ALLBLEND/S LIKELY POPS BACK DOWN TO CHANCE CATEGORY DUE TO THE AFOREMENTIONED UNCERTAINTY. OTHERWISE CHANCE POPS WILL BE THE RULE THROUGH THE EXTENDED. TEMPERATURES WILL GRADUALLY COOL FROM THE UPPER 80S EARLY IN THE PERIOD TO THE LOWER AND MIDDLE 80S BY SUNDAY AS THE UPPER LOW HAS MORE OF AN INFLUENCE. && .AVIATION /DISCUSSION FOR 161500Z IND TAF UPDATE/... ISSUED AT 923 AM EDT SUN JUN 16 2014 PULLED SHOWER MENTION BASED ON RADAR TRENDS AND HIGH RESOLUTION CONVECTIVE ALLOWING MODELS REFLECTIVITY PROGS. PREVIOUS DISCUSSION... OUTSIDE OF ANY CONVECTION...VFR EXPECTED THROUGH THE PERIOD. PRESENT INDICATIONS ARE THAT LARGEST THREAT FOR CONVECTION WILL BE THROUGH 18Z TODAY. SCATTERED CONVECTION WILL CONTINUE TO FIRE THIS MORNING AHEAD OF AN UPPER WAVE AND A WEAKENING SURFACE FRONT. CURRENT TRENDS ARE FOR KBMG TO SEE THE HIGHEST THREAT FOR THUNDERSTORMS...SO WILL USE TEMPO TSRA THERE FOR A COUPLE OF HOURS THIS MORNING. ELSEWHERE WILL USE VCSH. BEST FORCING WILL BE BEFORE 18Z SO THAT IS WHEN BEST CHANCES FOR CONVECTION WILL BE. HOWEVER CANNOT RULE OUT POP UP CONVECTION THIS AFTERNOON SO WILL CONTINUE VCSH MENTION DURING THE AFTERNOON. AFTER 00Z OR SO EXPECT DRY VFR CONDITIONS. && .IND WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SYNOPSIS...PUMA/RYAN NEAR TERM...RYAN SHORT TERM...PUMA LONG TERM....50 AVIATION...50/MK VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON TWITTER AND YOUTUBE AT: WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1023 AM EDT MON JUN 16 2014 .UPDATE... THE AVIATION SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 209 AM EDT MON JUN 16 2014 SUMMER WEATHER IS IN STORE THIS WEEK AS A BERMUDA HIGH WILL CONTINUE TO PUSH WARMER AND MORE HUMID AIR INTO THE OHIO VALLEY ON SOUTHERLY WINDS. A LINGERING FRONTAL BOUNDARY OVER CENTRAL INDIANA WILL BRING A FEW SCATTERED STORMS TODAY...HOWEVER AS THE WEEK PROGRESSES A RIDGE OF HIGH PRESSURE IS EXPECTED TO BUILD ALOFT AND ALLOW HOT SUMMER WEATHER BUILD ACROSS REGION. TEMPERATURES SHOULD REACH THE 90S FOR THE FIRST TIME IN 2014. CHANCES FOR THUNDERSTORMS WILL BECOME MORE NUMEROUS DURING THE SECOND HALF OF THE WEEK. && .NEAR TERM /REST OF TODAY/... ISSUED AT 951 AM EDT MON JUN 16 2014 SCATTERED CONVECTION IMPACTING THE FORECAST AREA THIS MORNING...ARCING ROUGHLY FROM THE SOUTHERN INDY METRO BACK TO THE SOUTHWEST INTO THE LOWER WABASH VALLEY AND BACK INTO SOUTH CENTRAL ILLINOIS. TEMPS WERE GENERALLY IN THE 70S AT 1330Z...WARMER WHERE RAIN WAS NOT OR HAD NOT FALLEN. CURRENT CONVECTIVE SETUP REQUIRING SOME CHANGES TO THE MORNING FORECAST. PRESENCE OF THE WEAK BOUNDARY AND A WAVE ALOFT CONTRIBUTING TO THE STORMS THIS MORNING. MESOANALYSIS INDICATING AN AXIS OF 1000-1500 J/KG MLCAPES ACROSS THE FORECAST AREA WITH 850MB WINDS AT AROUND 25KTS CONTRIBUTING TO CONVECTION AS WELL. WEAK UPPER WAVE WILL SHIFT EAST INTO THE EARLY AFTERNOON AS THE RIDGE ALOFT BEGINS TO EXPAND NORTH INTO THE REGION. COMBINED WITH A PROGRESSIVE WEAKENING OF BOUNDARY LAYER FLOW...EXPECT CONVECTIVE COVERAGE TO DIMINISH INTO THE AFTERNOON HOURS. WILL NEED TO MONITOR PROGRESSION OF STORMS IN SOUTH-CENTRAL ILLINOIS...AS CURRENT EXTRAPOLATION WOULD BRING THESE CELLS INTO THE LOWER WABASH VALLEY OVER THE NEXT FEW HOURS. CURRENT HRRR BRINGS THIS ACTIVITY INTO SOUTHWEST COUNTIES IN VICINITY OF THE REMNANT BOUNDARY BEFORE WEAKENING STORMS AS THE AFTERNOON PROGRESSES AND REFOCUSING MORE EXTENSIVE CONVECTION BACK TO THE WEST OVER THE MID MISSISSIPPI VALLEY. WILL MAINTAIN AN ISOLATED MENTION FOR STORMS THROUGH LATE AFTERNOON TO ACCOUNT FOR ANY CELLS THAT CAN GET GOING IN THE VICINITY OF THE BOUNDARY BUT OVERALL...AFTERNOON SHOULD BE DRIER THAN THIS MORNING HAS IN MOST AREAS. LOWERED HIGH TEMPS IN THE SOUTH A COUPLE DEGREES WITH CLOUDS/PRECIP THIS MORNING LIMITING TEMP RISES A BIT. EXPECT A STEAMY AFTERNOON...ESPECIALLY IN AREAS THAT RECEIVED RAIN THIS MORNING. ZONE AND GRID UPDATES OUT. && .SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/... ISSUED AT 209 AM EDT MON JUN 16 2014 MODELS SEEM TO HAVE A BIT BETTER IDEA ON THE PATTERN ALOFT THROUGH MID WEEK WHICH SHOULD ALLOW US TO REMOVE POPS THROUGH WEDNESDAY NIGHT. GFS AND NAM BOTH ALLOW A LOW ALOFT TO DIG OVER THE WESTERN UNITED STATES THROUGH WEDNESDAY. THE RESPONSE ACROSS THE EASTERN HALF OF THE COUNTRY IS A STRONG RIDGE OVER THE OHIO VALLEY WHICH WILL KEEP ANY PASSING SHORT WAVES WELL NORTH OF INDIANA. THE PATTERN WILL ALSO ALLOW SOME OF THE WARMEST TEMPERATURES OF THE YEAR SO FAR TO BUILD ACROSS CENTRAL INDIANA. FORECAST SOUNDINGS TONIGHT THROUGH WEDNESDAY SHOW 700MB TEMPS SURGING ABOVE 10C...EFFECTIVELY CAPPING THE COLUMN. FURTHERMORE CONVECTIVE TEMPERATURES REACH UNATTAINABLE LEVELS IN THE UPPER 90S AND LOW 100S. LARGE HIGH PRESSURE AT THE SURFACE CENTERED OVER THE SOUTHEASTERN STATES WILL KEEP ITS INFLUENCE OVER INDIANA AS WELL. ALL OF THIS WILL RESULT IN HOT...MOSTLY SUNNY DAYS AND WARM CLEAR NIGHTS. WILL USE A BLEND ON HIGH TEMPERATURES...WHICH WILL RESULT IN OUR FIRST 90S OF THE YEAR ON TUESDAY. WILL TREND LOWS AT OR ABOVE MAVMOS. && .LONG TERM /THURSDAY THROUGH SUNDAY/... ISSUED AT 225 AM EDT MON JUN 16 2014 MODELS ARE CLOSE ENOUGH THAT THE ALLBLEND INITIALIZATION WAS ACCEPTED FOR MOST ITEMS. AN UPPER RIDGE WILL BREAK DOWN EARLY IN THE LONG TERM ALLOWING AN UPPER LOW TO INFLUENCE THE WEATHER INTO THE WEEKEND. MODELS STILL DIFFER SOME ON EXACT PATH OF UPPER LOW...BUT IT WILL BE CLOSE ENOUGH FOR CHANCES FOR RAIN ACROSS THE AREA. DID KNOCK ALLBLEND/S LIKELY POPS BACK DOWN TO CHANCE CATEGORY DUE TO THE AFOREMENTIONED UNCERTAINTY. OTHERWISE CHANCE POPS WILL BE THE RULE THROUGH THE EXTENDED. TEMPERATURES WILL GRADUALLY COOL FROM THE UPPER 80S EARLY IN THE PERIOD TO THE LOWER AND MIDDLE 80S BY SUNDAY AS THE UPPER LOW HAS MORE OF AN INFLUENCE. && .AVIATION /DISCUSSION FOR 161500Z IND TAF UPDATE/... ISSUED AT 1023 AM EDT SUN JUN 16 2014 PULLED SHOWER MENTION BASED ON RADAR TRENDS AND HIGH RESOLUTION CONVECTIVE ALLOWING MODELS REFLECTIVITY PROGS. PREVIOUS DISCUSSION... OUTSIDE OF ANY CONVECTION...VFR EXPECTED THROUGH THE PERIOD. PRESENT INDICATIONS ARE THAT LARGEST THREAT FOR CONVECTION WILL BE THROUGH 18Z TODAY. SCATTERED CONVECTION WILL CONTINUE TO FIRE THIS MORNING AHEAD OF AN UPPER WAVE AND A WEAKENING SURFACE FRONT. CURRENT TRENDS ARE FOR KBMG TO SEE THE HIGHEST THREAT FOR THUNDERSTORMS...SO WILL USE TEMPO TSRA THERE FOR A COUPLE OF HOURS THIS MORNING. ELSEWHERE WILL USE VCSH. BEST FORCING WILL BE BEFORE 18Z SO THAT IS WHEN BEST CHANCES FOR CONVECTION WILL BE. HOWEVER CANNOT RULE OUT POP UP CONVECTION THIS AFTERNOON SO WILL CONTINUE VCSH MENTION DURING THE AFTERNOON. AFTER 00Z OR SO EXPECT DRY VFR CONDITIONS. && .IND WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SYNOPSIS...PUMA/RYAN NEAR TERM...RYAN SHORT TERM...PUMA LONG TERM....50 AVIATION...50/MK VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON TWITTER AND YOUTUBE AT: WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
951 AM EDT MON JUN 16 2014 .UPDATE... THE NEAR TERM SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 209 AM EDT MON JUN 16 2014 SUMMER WEATHER IS IN STORE THIS WEEK AS A BERMUDA HIGH WILL CONTINUE TO PUSH WARMER AND MORE HUMID AIR INTO THE OHIO VALLEY ON SOUTHERLY WINDS. A LINGERING FRONTAL BOUNDARY OVER CENTRAL INDIANA WILL BRING A FEW SCATTERED STORMS TODAY...HOWEVER AS THE WEEK PROGRESSES A RIDGE OF HIGH PRESSURE IS EXPECTED TO BUILD ALOFT AND ALLOW HOT SUMMER WEATHER BUILD ACROSS REGION. TEMPERATURES SHOULD REACH THE 90S FOR THE FIRST TIME IN 2014. CHANCES FOR THUNDERSTORMS WILL BECOME MORE NUMEROUS DURING THE SECOND HALF OF THE WEEK. && .NEAR TERM /REST OF TODAY/... ISSUED AT 951 AM EDT MON JUN 16 2014 SCATTERED CONVECTION IMPACTING THE FORECAST AREA THIS MORNING... ARCING ROUGHLY FROM THE SOUTHERN INDY METRO BACK TO THE SOUTHWEST INTO THE LOWER WABASH VALLEY AND BACK INTO SOUTH CENTRAL ILLINOIS. TEMPS WERE GENERALLY IN THE 70S AT 1330Z...WARMER WHERE RAIN WAS NOT OR HAD NOT FALLEN. CURRENT CONVECTIVE SETUP REQUIRING SOME CHANGES TO THE MORNING FORECAST. PRESENCE OF THE WEAK BOUNDARY AND A WAVE ALOFT CONTRIBUTING TO THE STORMS THIS MORNING. MESOANALYSIS INDICATING AN AXIS OF 1000-1500 J/KG MLCAPES ACROSS THE FORECAST AREA WITH 850MB WINDS AT AROUND 25KTS CONTRIBUTING TO CONVECTION AS WELL. WEAK UPPER WAVE WILL SHIFT EAST INTO THE EARLY AFTERNOON AS THE RIDGE ALOFT BEGINS TO EXPAND NORTH INTO THE REGION. COMBINED WITH A PROGRESSIVE WEAKENING OF BOUNDARY LAYER FLOW...EXPECT CONVECTIVE COVERAGE TO DIMINISH INTO THE AFTERNOON HOURS. WILL NEED TO MONITOR PROGRESSION OF STORMS IN SOUTH-CENTRAL ILLINOIS...AS CURRENT EXTRAPOLATION WOULD BRING THESE CELLS INTO THE LOWER WABASH VALLEY OVER THE NEXT FEW HOURS. CURRENT HRRR BRINGS THIS ACTIVITY INTO SOUTHWEST COUNTIES IN VICINITY OF THE REMNANT BOUNDARY BEFORE WEAKENING STORMS AS THE AFTERNOON PROGRESSES AND REFOCUSING MORE EXTENSIVE CONVECTION BACK TO THE WEST OVER THE MID MISSISSIPPI VALLEY. WILL MAINTAIN AN ISOLATED MENTION FOR STORMS THROUGH LATE AFTERNOON TO ACCOUNT FOR ANY CELLS THAT CAN GET GOING IN THE VICINITY OF THE BOUNDARY BUT OVERALL...AFTERNOON SHOULD BE DRIER THAN THIS MORNING HAS IN MOST AREAS. LOWERED HIGH TEMPS IN THE SOUTH A COUPLE DEGREES WITH CLOUDS/PRECIP THIS MORNING LIMITING TEMP RISES A BIT. EXPECT A STEAMY AFTERNOON...ESPECIALLY IN AREAS THAT RECEIVED RAIN THIS MORNING. ZONE AND GRID UPDATES OUT. && .SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/... ISSUED AT 209 AM EDT MON JUN 16 2014 MODELS SEEM TO HAVE A BIT BETTER IDEA ON THE PATTERN ALOFT THROUGH MID WEEK WHICH SHOULD ALLOW US TO REMOVE POPS THROUGH WEDNESDAY NIGHT. GFS AND NAM BOTH ALLOW A LOW ALOFT TO DIG OVER THE WESTERN UNITED STATES THROUGH WEDNESDAY. THE RESPONSE ACROSS THE EASTERN HALF OF THE COUNTRY IS A STRONG RIDGE OVER THE OHIO VALLEY WHICH WILL KEEP ANY PASSING SHORT WAVES WELL NORTH OF INDIANA. THE PATTERN WILL ALSO ALLOW SOME OF THE WARMEST TEMPERATURES OF THE YEAR SO FAR TO BUILD ACROSS CENTRAL INDIANA. FORECAST SOUNDINGS TONIGHT THROUGH WEDNESDAY SHOW 700MB TEMPS SURGING ABOVE 10C...EFFECTIVELY CAPPING THE COLUMN. FURTHERMORE CONVECTIVE TEMPERATURES REACH UNATTAINABLE LEVELS IN THE UPPER 90S AND LOW 100S. LARGE HIGH PRESSURE AT THE SURFACE CENTERED OVER THE SOUTHEASTERN STATES WILL KEEP ITS INFLUENCE OVER INDIANA AS WELL. ALL OF THIS WILL RESULT IN HOT...MOSTLY SUNNY DAYS AND WARM CLEAR NIGHTS. WILL USE A BLEND ON HIGH TEMPERATURES...WHICH WILL RESULT IN OUR FIRST 90S OF THE YEAR ON TUESDAY. WILL TREND LOWS AT OR ABOVE MAVMOS. && .LONG TERM /THURSDAY THROUGH SUNDAY/... ISSUED AT 225 AM EDT MON JUN 16 2014 MODELS ARE CLOSE ENOUGH THAT THE ALLBLEND INITIALIZATION WAS ACCEPTED FOR MOST ITEMS. AN UPPER RIDGE WILL BREAK DOWN EARLY IN THE LONG TERM ALLOWING AN UPPER LOW TO INFLUENCE THE WEATHER INTO THE WEEKEND. MODELS STILL DIFFER SOME ON EXACT PATH OF UPPER LOW...BUT IT WILL BE CLOSE ENOUGH FOR CHANCES FOR RAIN ACROSS THE AREA. DID KNOCK ALLBLEND/S LIKELY POPS BACK DOWN TO CHANCE CATEGORY DUE TO THE AFOREMENTIONED UNCERTAINTY. OTHERWISE CHANCE POPS WILL BE THE RULE THROUGH THE EXTENDED. TEMPERATURES WILL GRADUALLY COOL FROM THE UPPER 80S EARLY IN THE PERIOD TO THE LOWER AND MIDDLE 80S BY SUNDAY AS THE UPPER LOW HAS MORE OF AN INFLUENCE. && .AVIATION /DISCUSSION FOR 161200Z TAF ISSUANCE/... ISSUED AT 626 AM EDT SUN JUN 16 2014 OUTSIDE OF ANY CONVECTION...VFR EXPECTED THROUGH THE PERIOD. PRESENT INDICATIONS ARE THAT LARGEST THREAT FOR CONVECTION WILL BE THROUGH 18Z TODAY. SCATTERED CONVECTION WILL CONTINUE TO FIRE THIS MORNING AHEAD OF AN UPPER WAVE AND A WEAKENING SURFACE FRONT. CURRENT TRENDS ARE FOR KBMG TO SEE THE HIGHEST THREAT FOR THUNDERSTORMS...SO WILL USE TEMPO TSRA THERE FOR A COUPLE OF HOURS THIS MORNING. ELSEWHERE WILL USE VCSH. BEST FORCING WILL BE BEFORE 18Z SO THAT IS WHEN BEST CHANCES FOR CONVECTION WILL BE. HOWEVER CANNOT RULE OUT POP UP CONVECTION THIS AFTERNOON SO WILL CONTINUE VCSH MENTION DURING THE AFTERNOON. AFTER 00Z OR SO EXPECT DRY VFR CONDITIONS. && .IND WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SYNOPSIS...PUMA/RYAN NEAR TERM...RYAN SHORT TERM...PUMA LONG TERM....50 AVIATION...50 VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON TWITTER AND YOUTUBE AT: WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS GOODLAND KS
952 PM MDT TUE JUN 17 2014 .UPDATE... ISSUED AT 948 PM MDT TUE JUN 17 2014 NO MAJOR CHANGES MADE FOR THIS EVENING ALTHOUGH DID ADJUST DEWPOINTS UP CONSIDERABLY IN THE FAR EAST AS DRYLINE BEGINS TO REGRESS SLOWLY WESTWARD. LATEST NAM AND PREVIOUS GFS SHOW A MID-LEVEL SHORT WAVE TROUGH WILL LIFT OUT OF THE MAIN WESTERN U.S. UPPER LOW OVERNIGHT WITH AN ATTENDANT SURFACE LOW MOVING FROM COLORADO INTO NEBRASKA. THIS WILL TEND TO CHANGE SURFACE WINDS BACK TO THE SOUTHWEST BY LATER TONIGHT AND HALT THE WESTWARD PROGRESSION OF HIGHER DEWPOINTS. STILL A BIT OF UNCERTAINTY FOR TOMORROW AS TO WHERE DRYLINE WILL EVENTUALLY END UP WEDNESDAY AFTERNOON. NAM CONTINUES TO INDICATE POSSIBLE STORM DEVELOPMENT ON THE DRYLINE IN OUR EASTERN COUNTIES DURING THE AFTERNOON AND THEN ANOTHER SHOT AT STORMS MOVING EAST OUT OF COLORADO ASSOCIATED WITH THE UPPER TROUGH DURING THE EVENING. FORECAST CAPE DOESNT LOOK ALL THAT IMPRESSIVE RIGHT NOW FOR MAJOR SEVERE WITH THE EVENING STORMS. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 135 PM MDT TUE JUN 17 2014 LATEST WV IMAGERY AND RAP ANALYSIS SHOW SW FLOW CONTINUING ACROSS THE PLAINS WITH A LARGE CLOSED UPPER LOW OVER IDAHO. VERY DRY AIR CONTINUES TO ADVECT NORTHEAST WITHIN THE FLOW ALOFT INTO THE PLAINS WITH MONSOONAL SHOWERS/THUNDERSTORMS OVER THE HIGHER TERRAIN IN THE SOUTHERN ROCKIES. SURFACE LOW PRESSURE IS CURRENTLY IN PLACE OVER OUR CWA WITH THE STRONGEST PRESSURE GRADIENT WELL EAST OF OUR AREA. A DRY LINE IS ALSO EXTENDS FROM JUST EAST OF OBERLIN KANSAS AND OVER SOUTHWEST KANSAS. FOR THIS AFTERNOON AND EVENING...WHILE SHORT RANGE GUIDANCE IS SHOWING ISOLATED THUNDERSTORM ACTIVITY DEVELOP OVER THE NE PANHANDLE...A VERY DEEP/DRY AIR MASS IN PLACE OVER OUR CWA AND A TREND TOWARDS LOW TD VALUES MIXING NORTH SHOULD PRECLUDE ANY THUNDERSTORM CHANCES. IT STILL LOOKS LIKE WE COULD HAVE A PERIOD OF GUSTY WINDS THIS AFTERNOON BASED ON SHORT RANGE GUIDANCE...THIS DOESNT LOOK LIKE IT WILL BE WIDESPREAD AND SURFACE PATTERN/GRADIENT IS FAIRLY WEAK OVER OUR CWA. RH VALUES HAVE DECREASED SIGNIFICANTLY HOWEVER WITH FUELS STILL QUESTIONABLE AND WINDS MARGINAL NO RED FLAG WARNING IS PLANNED THIS AFTERNOON. WEDNESDAY...WHILE STILL ABOVE NORMAL HIGH TEMPERATURES SHOULD BE COOLER THAN THE LAST FEW DAYS AS THE AIR MASS ALOFT BEGINS TO CHANGE WITH APPROACHING UPPER TROUGH AND APPROACHING COLD FRONT. WE COULD START TO SEE ISOLATED TO WIDELY SCATTERED THUNDERSTORMS DEVELOPING ALONG A CONVERGENCE ZONE IN OUR EASTERN CWA BY LATE AFTERNOON WITH BETTER COVERAGE AFTER 00Z (7PM CDT). SEVERE THREAT WILL BE LIMITED WED AFTERNOON DUE TO QUESTIONABLE THUNDERSTORM COVERAGE AND LIMITED SHEER. HOWEVER...DEPENDING ON THE LOCATION OF TROUGH AXIS WE COULD SEE MODERATE INSTABILITY AND STEEP LAPSE RATES IN PLACE OVER THE EASTERN CWA THAT COULD SUPPORT AN ISOLATED HAIL/DAMAGING WIND THREAT THROUGH WED AFTERNOON. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 247 PM MDT TUE JUN 17 2014 WEDNESDAY EVENING AN UPPER LEVEL SHORT WAVE TROUGH WILL MOVE OVER THE TRI-STATE AREA AHEAD OF THE MAIN TROUGH WHICH WILL MOVE THROUGH DURING THE EVENING/OVERNIGHT HOURS. AS THE MAIN TROUGH MOVES THROUGH...700-300MB FRONTOGENESIS INCREASES OVER THE NORTHERN HALF OF THE AREA. LOW LEVEL MIXING RATIOS...SPECIFICALLY THOSE AT 750MB...INCREASE AHEAD OF THE MAIN TROUGH AS THE TROUGH MOVES THROUGH. AT THE SURFACE THE DRY LINE OVER NORTON AND GRAHAM COUNTIES WILL MOVE BACK WEST ONE OR TWO TIERS OF COUNTIES AS THE SURFACE LOW OVER EASTERN COLORADO DEEPENS. LOW LEVEL MOISTURE WILL ALSO INCREASE OVER THE EASTERN PART OF THE AREA EAST OF RETREATING DRY LINE. IN ADDITION A COLD FRONT WILL BEGIN TO ADVANCE SOUTHEAST ACROSS THE AREA AS THE SURFACE LOW DEEPENS. AS IT MOVES SOUTHEAST RAPID PRESSURE RISES WILL ACCOMPANY THE FRONT AND THE LOW LEVEL JET WILL STRENGTHEN TO NEAR 50 KTS JUST BEHIND THE FRONTAL BOUNDARY. WINDS WILL LIKELY GUST TO 45 MPH BEHIND THE FRONT. DURING THE OVERNIGHT HOURS THE ISALLOBARIC TREND DECLINES SO WINDS SHOULD NOT BE AS STRONG AS THE FRONT CONTINUES TO MOVE THROUGH...EXITING THE AREA AROUND SUNRISE. MEANWHILE THE MAIN UPPER LEVEL TROUGH WILL DEEPEN OVER THE AREA AROUND MIDNIGHT. AHEAD OF IT TEMPERATURE LAPSE RATES ABOVE 850 TO 750 MB OR SO STEEPEN. THE ADDED EFFECT OF INCREASED LOW LEVEL MIXING RATIOS WILL CREATE ELEVATED CAPE OF 1000-2500 J/KG...WITH THE HIGHEST CAPE OVER FAR EASTERN NORTON AND GRAHAM COUNTIES. 0-6KM BULK SHEAR IS AROUND 50KTS SO SEVERE THUNDERSTORMS WILL BE LIKELY. TRIED TO HIGHLIGHT THE MOST LIKELY TIME/LOCATION OF THE SEVERE STORMS IN THE FORECAST. THIS SETUP IS SIMILAR TO SATURDAY EVENING AS FAR AS A SEVERE WIND POTENTIAL WITH STORMS FORMING UPSTREAM OF A COLD FRONT WITH STRONG ISALLOBARIC TRENDS. WOULD NOT BE SURPRISED IF STORMS MERGE INTO A SQUALL LINE BEHIND THE FRONT AND IF HIGH WINDS DEVELOP BEHIND THE STORMS SIMILAR TO SATURDAY NIGHT. TOWARD SUNRISE THE UPPER LEVEL TROUGH MOVES NORTHEAST OF THE AREA WITH DRIER MORE STABLE AIR FOLLOWING THE COLD FRONT IN FROM THE WEST. THURSDAY WILL BE COOLER AND DRY DUE TO A CAPPED ENVIRONMENT. THURSDAY LATE AFTERNOON/EVENING A WEAKER 500MB SHORT WAVE TROUGH DEVELOPS OVER THE COLORADO BORDER. THE DRY LINE/COLD FRONT WILL RETREAT BACK INTO THE FAR SOUTHEAST PART OF THE AREA AS THE LEE TROUGH OVER SOUTHEAST COLORADO DEEPENS. THIS WILL ALLOW LOW LEVEL MIXING RATIOS TO INCREASE EAST OF THE SURFACE BOUNDARY AND ALLOW ELEVATED CAPE TO DEVELOP AHEAD OF THE 500MB TROUGH. AS A RESULT WILL HAVE SOME LOW RAINFALL CHANCES FOR STORMS AHEAD OF THE TROUGH. AS THE NIGHT PROGRESSES THE SURFACE BOUNDARY WILL MOVE NORTH FOLLOWING THE RETREATING UPPER LEVEL TROUGH. DUE TO SOUNDINGS NOT LOOKING VERY SUITABLE FOR MORE WIDESPREAD STORM COVERAGE...WILL KEEP PRECIP. CHANCES FAIRLY LOW DESPITE ELEVATED CAPE OF 1000-2000J/KG. FRIDAY THROUGH TUESDAY WILL CONTINUE TO BE ACTIVE AS THE CLOSED LOW OVER THE NORTHERN CONUS SLOWLY PLODS EAST WITH NUMEROUS SMALLER TROUGHS SOUTH OF IT MOVING OVER THE TRI-STATE AREA. THE BEST CHANCE FOR RAINFALL WILL BE SUNDAY NIGHT INTO MONDAY WHEN A DEEPER UPPER LEVEL TROUGH MOVES OVER THE AREA. GEFS MEMBERS HAVE HIGH CHANCES FOR RAINFALL FOR THAT NIGHT WHICH ADDS CONFIDENCE THAT THE AREA WILL RECEIVE RAINFALL. FAIRLY GOOD CHANCES FOR RAINFALL CONTINUE THROUGH MONDAY NIGHT AS SHORT WAVE TROUGHS CONTINUE TO MOVE OVER THE AREA. SINCE THESE SMALLER SCALE TROUGHS ARE TIED TO THE EASTWARD PROGRESS OF THE CLOSED LOW OVER THE NORTHERN CONUS...WOULD NOT BE SURPRISED IF MODELS PUSH THE HIGHER RAINFALL CHANCES AHEAD A DAY OR TWO BY THE TIME NEXT WEEK ARRIVES SINCE MODELS TEND TO MOVE CLOSED LOWS TOO FAST. TEMPERATURES THROUGH THE PERIOD WILL BE AROUND 10 DEGREES ABOVE NORMAL FRIDAY THEN COOL TO NEAR NORMAL SUNDAY THROUGH TUESDAY. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING) ISSUED AT 509 PM MDT TUE JUN 17 2014 VFR CONDITIONS WILL CONTINUE THROUGH THE TAF PERIOD. SOUTHWEST FLOW WILL CONTINUE TO BRING IN DRY AIR TONIGHT INTO EARLY TOMORROW. SOUTHWEST WINDS SHOULD REMAIN FAIRLY LIGHT AROUND 5 TO 10 KTS OVERNIGHT...WITH KGLD EXPERIENCING SOME SLIGHTLY STRONGER SOUTHWEST WINDS AT 10 TO 15 KTS JUST BEFORE SUNSET. A SURFACE BOUNDARY WILL MOVE THROUGH THE REGION TOMORROW WHICH WILL SHIFT WINDS TO THE WEST NORTHWEST. WINDS WILL INCREASE MIDDAY AND DURING THE AFTERNOON TOMORROW WITH GUSTS BETWEEN 20 TO 25 KTS. THUNDERSTORMS COULD DEVELOP NEAR THE TERMINALS LATE TOMORROW AFTERNOON AS A DRYLINE REGRESSES WEST OVER THE REGION AND AN UPPER LEVEL TROUGH MOVES EAST WITH A COLD FRONT NEARING THE REGION. HOWEVER...HAVE LEFT MENTION OF THUNDERSTORMS OUT OF THE TAFS FOR NOW SINCE LIKELY TIMING FOR DEVELOPMENT WILL BE AFTER 0Z. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...DLF SHORT TERM...DR LONG TERM...JTL AVIATION...ALW
AREA FORECAST DISCUSSION
NWS GOODLAND KS
519 PM MDT TUE JUN 17 2014 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 135 PM MDT TUE JUN 17 2014 LATEST WV IMAGERY AND RAP ANALYSIS SHOW SW FLOW CONTINUING ACROSS THE PLAINS WITH A LARGE CLOSED UPPER LOW OVER IDAHO. VERY DRY AIR CONTINUES TO ADVECT NORTHEAST WITHIN THE FLOW ALOFT INTO THE PLAINS WITH MONSOONAL SHOWERS/THUNDERSTORMS OVER THE HIGHER TERRAIN IN THE SOUTHERN ROCKIES. SURFACE LOW PRESSURE IS CURRENTLY IN PLACE OVER OUR CWA WITH THE STRONGEST PRESSURE GRADIENT WELL EAST OF OUR AREA. A DRY LINE IS ALSO EXTENDS FROM JUST EAST OF OBERLIN KANSAS AND OVER SOUTHWEST KANSAS. FOR THIS AFTERNOON AND EVENING...VERY HIGH CAPE VALUES HAVE DEVELOPED AND CIN HAS WEAKENED SOME OVER FAR EASTER PARTS OF OUR OVER NORTHWESTERN PARTS OF THE CWA ACROSS SW PORTIONS OF NEBRASKA. WHILE SHORT RANGE GUIDANCE IS SHOWING ISOLATED THUNDERSTORM ACTIVITY DEVELOP OVER THE NE PANHANDLE...A VERY DEEP/DRY AIR MASS IN PLACE OVER OUR CWA AND A TREND TOWARDS LOW TD VALUES MIXING NORTH SHOULD PRECLUDE ANY THUNDERSTORM CHANCES. IT STILL LOOKS LIKE WE COULD HAVE A PERIOD OF GUSTY WINDS THIS AFTERNOON BASED ON SHORT RANGE GUIDANCE...THIS DOESNT LOOK LIKE IT WILL BE WIDESPREAD AND SURFACE PATTERN/GRADIENT IS FAIRLY WEAK OVER OUR CWA. RH VALUES HAVE DECREASED SIGNIFICANTLY HOWEVER WITH FUELS STILL QUESTIONABLE AND WINDS MARGINAL NO RED FLAG WARNING IS PLANNED THIS AFTERNOON. WEDNESDAY...WHILE STILL ABOVE NORMAL HIGH TEMPERATURES SHOULD BE COOLER THAN THE LAST FEW DAYS AS THE AIR MASS ALOFT BEGINS TO CHANGE WITH APPROACHING UPPER TROUGH AND APPROACHING COLD FRONT. WE COULD START TO SEE ISOLATED TO WIDELY SCATTERED THUNDERSTORMS DEVELOPING ALONG A CONVERGENCE ZONE IN OUR EASTERN CWA BY LATE AFTERNOON WITH BETTER COVERAGE AFTER 00Z (7PM CDT). SEVERE THREAT WILL BE LIMITED WED AFTERNOON DUE TO QUESTIONABLE THUNDERSTORM COVERAGE AND LIMITED SHEER. HOWEVER...DEPENDING ON THE LOCATION OF TROUGH AXIS WE COULD SEE MODERATE INSTABILITY AND STEEP LAPSE RATES IN PLACE OVER THE EASTERN CWA THAT COULD SUPPORT AN ISOLATED HAIL/DAMAGING WIND THREAT THROUGH WED AFTERNOON. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 247 PM MDT TUE JUN 17 2014 WEDNESDAY EVENING AN UPPER LEVEL SHORT WAVE TROUGH WILL MOVE OVER THE TRI-STATE AREA AHEAD OF THE MAIN TROUGH WHICH WILL MOVE THROUGH DURING THE EVENING/OVERNIGHT HOURS. AS THE MAIN TROUGH MOVES THROUGH...700-300MB FRONTOGENESIS INCREASES OVER THE NORTHERN HALF OF THE AREA. LOW LEVEL MIXING RATIOS...SPECIFICALLY THOSE AT 750MB...INCREASE AHEAD OF THE MAIN TROUGH AS THE TROUGH MOVES THROUGH. AT THE SURFACE THE DRY LINE OVER NORTON AND GRAHAM COUNTIES WILL MOVE BACK WEST ONE OR TWO TIERS OF COUNTIES AS THE SURFACE LOW OVER EASTERN COLORADO DEEPENS. LOW LEVEL MOISTURE WILL ALSO INCREASE OVER THE EASTERN PART OF THE AREA EAST OF RETREATING DRY LINE. IN ADDITION A COLD FRONT WILL BEGIN TO ADVANCE SOUTHEAST ACROSS THE AREA AS THE SURFACE LOW DEEPENS. AS IT MOVES SOUTHEAST RAPID PRESSURE RISES WILL ACCOMPANY THE FRONT AND THE LOW LEVEL JET WILL STRENGTHEN TO NEAR 50 KTS JUST BEHIND THE FRONTAL BOUNDARY. WINDS WILL LIKELY GUST TO 45 MPH BEHIND THE FRONT. DURING THE OVERNIGHT HOURS THE ISALLOBARIC TREND DECLINES SO WINDS SHOULD NOT BE AS STRONG AS THE FRONT CONTINUES TO MOVE THROUGH...EXITING THE AREA AROUND SUNRISE. MEANWHILE THE MAIN UPPER LEVEL TROUGH WILL DEEPEN OVER THE AREA AROUND MIDNIGHT. AHEAD OF IT TEMPERATURE LAPSE RATES ABOVE 850 TO 750 MB OR SO STEEPEN. THE ADDED EFFECT OF INCREASED LOW LEVEL MIXING RATIOS WILL CREATE ELEVATED CAPE OF 1000-2500 J/KG...WITH THE HIGHEST CAPE OVER FAR EASTERN NORTON AND GRAHAM COUNTIES. 0-6KM BULK SHEAR IS AROUND 50KTS SO SEVERE THUNDERSTORMS WILL BE LIKELY. TRIED TO HIGHLIGHT THE MOST LIKELY TIME/LOCATION OF THE SEVERE STORMS IN THE FORECAST. THIS SETUP IS SIMILAR TO SATURDAY EVENING AS FAR AS A SEVERE WIND POTENTIAL WITH STORMS FORMING UPSTREAM OF A COLD FRONT WITH STRONG ISALLOBARIC TRENDS. WOULD NOT BE SURPRISED IF STORMS MERGE INTO A SQUALL LINE BEHIND THE FRONT AND IF HIGH WINDS DEVELOP BEHIND THE STORMS SIMILAR TO SATURDAY NIGHT. TOWARD SUNRISE THE UPPER LEVEL TROUGH MOVES NORTHEAST OF THE AREA WITH DRIER MORE STABLE AIR FOLLOWING THE COLD FRONT IN FROM THE WEST. THURSDAY WILL BE COOLER AND DRY DUE TO A CAPPED ENVIRONMENT. THURSDAY LATE AFTERNOON/EVENING A WEAKER 500MB SHORT WAVE TROUGH DEVELOPS OVER THE COLORADO BORDER. THE DRY LINE/COLD FRONT WILL RETREAT BACK INTO THE FAR SOUTHEAST PART OF THE AREA AS THE LEE TROUGH OVER SOUTHEAST COLORADO DEEPENS. THIS WILL ALLOW LOW LEVEL MIXING RATIOS TO INCREASE EAST OF THE SURFACE BOUNDARY AND ALLOW ELEVATED CAPE TO DEVELOP AHEAD OF THE 500MB TROUGH. AS A RESULT WILL HAVE SOME LOW RAINFALL CHANCES FOR STORMS AHEAD OF THE TROUGH. AS THE NIGHT PROGRESSES THE SURFACE BOUNDARY WILL MOVE NORTH FOLLOWING THE RETREATING UPPER LEVEL TROUGH. DUE TO SOUNDINGS NOT LOOKING VERY SUITABLE FOR MORE WIDESPREAD STORM COVERAGE...WILL KEEP PRECIP. CHANCES FAIRLY LOW DESPITE ELEVATED CAPE OF 1000-2000J/KG. FRIDAY THROUGH TUESDAY WILL CONTINUE TO BE ACTIVE AS THE CLOSED LOW OVER THE NORTHERN CONUS SLOWLY PLODS EAST WITH NUMEROUS SMALLER TROUGHS SOUTH OF IT MOVING OVER THE TRI-STATE AREA. THE BEST CHANCE FOR RAINFALL WILL BE SUNDAY NIGHT INTO MONDAY WHEN A DEEPER UPPER LEVEL TROUGH MOVES OVER THE AREA. GEFS MEMBERS HAVE HIGH CHANCES FOR RAINFALL FOR THAT NIGHT WHICH ADDS CONFIDENCE THAT THE AREA WILL RECEIVE RAINFALL. FAIRLY GOOD CHANCES FOR RAINFALL CONTINUE THROUGH MONDAY NIGHT AS SHORT WAVE TROUGHS CONTINUE TO MOVE OVER THE AREA. SINCE THESE SMALLER SCALE TROUGHS ARE TIED TO THE EASTWARD PROGRESS OF THE CLOSED LOW OVER THE NORTHERN CONUS...WOULD NOT BE SURPRISED IF MODELS PUSH THE HIGHER RAINFALL CHANCES AHEAD A DAY OR TWO BY THE TIME NEXT WEEK ARRIVES SINCE MODELS TEND TO MOVE CLOSED LOWS TOO FAST. TEMPERATURES THROUGH THE PERIOD WILL BE AROUND 10 DEGREES ABOVE NORMAL FRIDAY THEN COOL TO NEAR NORMAL SUNDAY THROUGH TUESDAY. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING) ISSUED AT 509 PM MDT TUE JUN 17 2014 VFR CONDITIONS WILL CONTINUE THROUGH THE TAF PERIOD. SOUTHWEST FLOW WILL CONTINUE TO BRING IN DRY AIR TONIGHT INTO EARLY TOMORROW. SOUTHWEST WINDS SHOULD REMAIN FAIRLY LIGHT AROUND 5 TO 10 KTS OVERNIGHT...WITH KGLD EXPERIENCING SOME SLIGHTLY STRONGER SOUTHWEST WINDS AT 10 TO 15 KTS JUST BEFORE SUNSET. A SURFACE BOUNDARY WILL MOVE THROUGH THE REGION TOMORROW WHICH WILL SHIFT WINDS TO THE WEST NORTHWEST. WINDS WILL INCREASE MIDDAY AND DURING THE AFTERNOON TOMORROW WITH GUSTS BETWEEN 20 TO 25 KTS. THUNDERSTORMS COULD DEVELOP NEAR THE TERMINALS LATE TOMORROW AFTERNOON AS A DRYLINE REGRESSES WEST OVER THE REGION AND AN UPPER LEVEL TROUGH MOVES EAST WITH A COLD FRONT NEARING THE REGION. HOWEVER...HAVE LEFT MENTION OF THUNDERSTORMS OUT OF THE TAFS FOR NOW SINCE LIKELY TIMING FOR DEVELOPMENT WILL BE AFTER 0Z. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...DR LONG TERM...JTL AVIATION...ALW
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
232 AM CDT Mon Jun 16 2014 ...UPDATE TO LONG TERM... .SHORT TERM...(Today and tonight) ISSUED AT 126 AM CDT MON JUN 16 2014 Models this morning remain in good agreement with warm mid level temperatures spreading into western Kansas early this morning. 700mb temperatures are forecast to be around +14c by late morning. Under this warm mid layer air...a dryline which will be located near the Colorado border at 12z Monday will move east and by 18z is currently forecast to be located near Dodge City where it is expected to become nearly stationary. The 850mb to 700mb temperatures from the NAM and GFS indicate a decent warming trend across western Kansas today. Net 24hour temperature change in 850mb temperatures from 00z Monday to 00z Tuesday is 6c to near 10c, and 700mb temperature change varied from 4c to 6c. Using this as a guide for highs the previous forecast still looks on track with highs in the mid 90s to near 100. The warmer temperatures will be just west of the dryline. Also west of this dryline the dewpoints will fall back into the 20 to 25 degree range as gusty southwest winds develop. Based on expected highs the afternoon relative humidity values will bottom out near 10 percent for several hours west of line from near Liberal to Ness City. This will enhance the fire danger levels, however given the greening of fuels from the recent rains and based on latest updated fuel status will not issue a red flag warning despite the gusty winds and low relative humidities. Ahead/east of this dryline the surface dewpoints are still expected be in the upper 60s to lower 70s as southerly wind increase to around 30 mph by late morning as stronger winds in the boundary layer start to mix down to the surface. Based on the mean mix layer winds from the NAM and GFS the winds are expected to approach/meet wind advisory criteria by late morning and then continue through the remainder of the day. NAM Cape values greater than 2000 j/kg are forecast by late day. 0-6km shear currently is expected to be 30 to 35 knots. Based on this can not completely able to rule out a few strong or marginally thunderstorms late today, however given the warm mid level temperatures, weak cin from the forecast model soundings at 00z Tuesday, and lack of any significant forcing current confidence of late day/evening convection is not very highs along the dryline. At this time am leaning against inserting a any isolated thunderstorms along the dryline late this afternoon and early evening as the dryline. Will however take a closer look at the ARW,NMM and 06z NAM and adjust this if needed. Retreating dryline overnight will allow winds to back to the southeast overnight for much of western Kansas and dewpoints to rise back into the 60s. Based on expected wind speeds and increasing dewpoints the lows tonight in the upper 60s to lower 70s still appears reasonable. .LONG TERM...(Tuesday through Sunday) ISSUED AT 230 AM CDT MON JUN 16 2014 Medium range models indicate a southwesterly flow aloft prevailing across the Western High Plains through mid week. Meanwhile, a strong upper level trough of low pressure across the Pacific Northwest will turn easterly into the Northern Rockies Tuesday. Even with ample moisture present across central and portions of western Kansas, fairly dry conditions are expected to continue early in the period due to a weakening flow aloft. Thunderstorms will be possible Wednesday as the upper level trough axis pushes further eastward into the western Northern Plains and the Colorado Rockies while becoming more negatively tilted. As the upper level system approaches, an already developed dryline will begin to sharpen generally somewhere across southwest Kansas. Although to what degree remains uncertain, dynamic support aloft will increase as an upper level jet exiting the approaching trough axis, lifts northeast out of the Colorado Rockies into the Northern Plains. Even though the bulk of the system`s focus will pass to our north, thunderstorms will still be possible along and ahead of the dryline late Wednesday afternoon into Wednesday evening as the cap weakens. Steep low/mid level lapse rates and SBCAPE values in excess of 2500 J/KG will be enough to support the potential for severe storms across central and portions of southwest Kansas. The potential for thunderstorms is expected to continue into Thursday for portions of central Kansas as an attendant frontal boundary to the upper level trough pushes southeast across the area before stalling out and lifting back to the north. Warmer temperatures will remain across western Kansas Tuesday as a prevailing lee side trough of low pressure continues to influence a southerly flow across western Kansas. Drawing warmer air northward, the GFS/ECMWF show H85 temperatures up into the mid to upper 20s(C) across central Kansas to a little above 30C in extreme southwest Kansas. Widespread 90s(F) are likely across central and southwest Kansas Tuesday afternoon with near 100F possible in some locations. Similar temperatures are likely again Wednesday with little change expected to the overall air mass in place across the Western High Plains. Slightly cooler temperatures are forecast Thursday as a cold front pushes through western Kansas. && .AVIATION...(For the 06Z TAFS through 06Z Monday night) ISSUED AT 1221 AM CDT MON JUN 16 2014 Southeast winds at 10 to around 15knots continue overnight and will draw more humid air into western Kansas. Given the low level winds overnight fog is not anticipated but some scattered MVFR status will be possible given the increasing moisture in the lower levels. Latest HRRR also indicating this, especially in the Hays area so will introduce a period of MVFR ceiling in status between 06 and 12z. A dryline that will be located near the Colorado border at 12z Monday will move east early in the day. This dryline is currently expected to be located near Hays and DDC by mid day. west of the dryline southwest winds at around 20knots are expected. Near and east of this dryline southerly winds at near 25 knots are expected to develop by late morning. NAM BUFR soundings indicating VFR conditions throughout the day Monday. && .PRELIMINARY POINT TEMPS/POPS... DDC 99 70 97 70 / 10 10 10 10 GCK 99 68 98 68 / 0 10 10 10 EHA 98 65 98 67 / 0 10 10 10 LBL 100 69 99 68 / 0 10 10 10 HYS 98 70 97 72 / 10 10 10 10 P28 97 73 96 74 / 10 10 10 10 && .DDC WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY from Noon today to 8 PM CDT this evening FOR KSZ046-064>066-077>081-086>090. && $$ SHORT TERM...Burgert LONG TERM...JJohnson AVIATION...Burgert
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
133 AM CDT Mon Jun 16 2014 ...Updated Synopsis and short term discussion... .SYNOPSIS... ISSUED AT 126 AM CDT MON JUN 16 2014 At 00z Monday a 500mb trough was located along western United States with a +120kt upper level jet streak located west of the upper level trough just off the northwest United States Coast. A southwest flow extended from the based of the upper level trough into the Central Plains with a subtle upper level disturbance embedded in this flow. This disturbance was located near southern California at 00z Monday. 700mb temperatures across the central and southern Plains ranged from +7 at Topeka to +10c at Dodge City to +12 at Amarillo and +15c at Albuquerque. 850mb temperatures varied from +17c At North Platte to +20 at Dodge City to +25 at Amarillo. The better 850mb moisture was located from Topeka to Oklahoma City. At the surface a southeasterly flow was present from central Oklahoma into southwest Kansas. Dewpoints in the lower 70s were present across northern Oklahoma near the Kansas border and these dewpoints were begin advected into Kansas from the southeasterly wind. && .SHORT TERM...(Today and tonight) ISSUED AT 126 AM CDT MON JUN 16 2014 Models this morning remain in good agreement with warm mid level temperatures spreading into western Kansas early this morning. 700mb temperatures are forecast to be around +14c by late morning. Under this warm mid layer air...a dryline which will be located near the Colorado border at 12z Monday will move east and by 18z is currently forecast to be located near Dodge City where it is expected to become nearly stationary. The 850mb to 700mb temperatures from the NAM and GFS indicate a decent warming trend across western Kansas today. Net 24hour temperature change in 850mb temperatures from 00z Monday to 00z Tuesday is 6c to near 10c, and 700mb temperature change varied from 4c to 6c. Using this as a guide for highs the previous forecast still looks on track with highs in the mid 90s to near 100. The warmer temperatures will be just west of the dryline. Also west of this dryline the dewpoints will fall back into the 20 to 25 degree range as gusty southwest winds develop. Based on expected highs the afternoon relative humidity values will bottom out near 10 percent for several hours west of line from near Liberal to Ness City. This will enhance the fire danger levels, however given the greening of fuels from the recent rains and based on latest updated fuel status will not issue a red flag warning despite the gusty winds and low relative humidities. Ahead/east of this dryline the surface dewpoints are still expected be in the upper 60s to lower 70s as southerly wind increase to around 30 mph by late morning as stronger winds in the boundary layer start to mix down to the surface. Based on the mean mix layer winds from the NAM and GFS the winds are expected to approach/meet wind advisory criteria by late morning and then continue through the remainder of the day. NAM Cape values greater than 2000 j/kg are forecast by late day. 0-6km shear currently is expected to be 30 to 35 knots. Based on this can not completely able to rule out a few strong or marginally thunderstorms late today, however given the warm mid level temperatures, weak cin from the forecast model soundings at 00z Tuesday, and lack of any significant forcing current confidence of late day/evening convection is not very highs along the dryline. At this time am leaning against inserting a any isolated thunderstorms along the dryline late this afternoon and early evening as the dryline. Will however take a closer look at the ARW,NMM and 06z NAM and adjust this if needed. Retreating dryline overnight will allow winds to back to the southeast overnight for much of western Kansas and dewpoints to rise back into the 60s. Based on expected wind speeds and increasing dewpoints the lows tonight in the upper 60s to lower 70s still appears reasonable. .LONG TERM...(Monday night through Sunday) ISSUED AT 243 PM CDT SUN JUN 15 2014 For Tuesday into Wednesday, a Pacific Northwest upper low and trough will slowly move east and into the Plains by late Wednesday. This system will give a chance for showers and thunderstorms by mainly Wednesday afternoon into the evening. Some storms may be strong to severe ahead of a dryline and cold front with dewpoints in the 60s and veering mid level winds. Ahead of this upper level storm system, high temps will be rather warm and in the mid to upper 90s on Tuesday afternoon, and low to mid 90s on Wednesday afternoon. Winds will be gusty from the south each day at 20 to 35 mph. For the period of Thursday into next Weekend, the upper level storm system will move slowly east on Thursday with a possibility of lingering storms in parts of south central Kansas. The GFS model is the slowest with movement of the system. More scattered storms are possible into the Weekend but the upper flow looks very weak for any organized widespread convection. High temperatures will be a little cooler with highs around 90 and lows in the 60s. && .AVIATION...(For the 06Z TAFS through 06Z Monday night) ISSUED AT 1221 AM CDT MON JUN 16 2014 Southeast winds at 10 to around 15knots continue overnight and will draw more humid air into western Kansas. Given the low level winds overnight fog is not anticipated but some scattered MVFR status will be possible given the increasing moisture in the lower levels. Latest HRRR also indicating this, especially in the Hays area so will introduce a period of MVFR ceiling in status between 06 and 12z. A dryline that will be located near the Colorado border at 12z Monday will move east early in the day. This dryline is currently expected to be located near Hays and DDC by mid day. west of the dryline southwest winds at around 20knots are expected. Near and east of this dryline southerly winds at near 25 knots are expected to develop by late morning. NAM BUFR soundings indicating VFR conditions throughout the day Monday. && .PRELIMINARY POINT TEMPS/POPS... DDC 99 72 96 71 / 10 10 10 20 GCK 98 69 97 69 / 0 10 10 10 EHA 97 67 97 68 / 0 10 10 10 LBL 99 69 98 69 / 10 10 10 20 HYS 97 71 96 73 / 10 10 10 10 P28 97 73 95 75 / 10 10 10 20 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...Burgert SHORT TERM...Burgert LONG TERM...Kruse AVIATION...Burgert
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1224 AM CDT Mon Jun 16 2014 ...Updated aviation discussion... .SHORT TERM...(This evening through Monday) ISSUED AT 115 PM CDT SUN JUN 15 2014 Tonight: A pretty quiet night is expected across the forecast area. The exception to this is across Barber county where there is a slight chance of overnight thunderstorms. There is enough mu cape (3500 J/kg), fairly steep 700-500-hPa lapse rates of 6.7 C/km, and 40 kt of effective shear to produce marginally severe hail should a storm develop. The overall trend, particularly with the tail end of the HRRR, is that activity will be E/SE of Barber county, though. Otherwise, elsewhere will see dry conditions with lows in the 60s/70s and southerly winds through the overnight. Tomorrow: Hot! Lee troughing will strengthen tomorrow with SSW becoming breezy to low end wind advisory. Gone with the CON MOS for wind speeds for now as the mixed down procedure winds look too high. Something to be watched if an advisory is needed or not. Marginal event though. Highs will be in the upper 90s. Didn`t want to go 100F just yet as the recent rains might keep temps down a degree or two. There could be elevated fire weather conditions just in terms of RH`s and wind speeds out west, however, with the recent green up from all the MCS rains, don`t think a headline is required. The dryline will mix east through the day and then retreat back west tomorrow evening. The WRF-NMM core is the only model indicating some precip, but not really keen on that for now. Will keep pops AB 14 percent. .LONG TERM...(Monday night through Sunday) ISSUED AT 243 PM CDT SUN JUN 15 2014 For Tuesday into Wednesday, a Pacific Northwest upper low and trough will slowly move east and into the Plains by late Wednesday. This system will give a chance for showers and thunderstorms by mainly Wednesday afternoon into the evening. Some storms may be strong to severe ahead of a dryline and cold front with dewpoints in the 60s and veering mid level winds. Ahead of this upper level storm system, high temps will be rather warm and in the mid to upper 90s on Tuesday afternoon, and low to mid 90s on Wednesday afternoon. Winds will be gusty from the south each day at 20 to 35 mph. For the period of Thursday into next Weekend, the upper level storm system will move slowly east on Thursday with a possibility of lingering storms in parts of south central Kansas. The GFS model is the slowest with movement of the system. More scattered storms are possible into the Weekend but the upper flow looks very weak for any organized widespread convection. High temperatures will be a little cooler with highs around 90 and lows in the 60s. && .AVIATION...(For the 06Z TAFS through 06Z Monday night) ISSUED AT 1221 AM CDT MON JUN 16 2014 Southeast winds at 10 to around 15knots continue overnight and will draw more humid air into western Kansas. Given the low level winds overnight fog is not anticipated but some scattered MVFR status will be possible given the increasing moisture in the lower levels. Latest HRRR also indicating this, especially in the Hays area so will introduce a period of MVFR ceiling in status between 06 and 12z. A dryline that will be located near the Colorado border at 12z Monday will move east early in the day. This dryline is currently expected to be located near Hays and DDC by mid day. west of the dryline southwest winds at around 20knots are expected. Near and east of this dryline southerly winds at near 25 knots are expected to develop by late morning. NAM BUFR soundings indicating VFR conditions throughout the day Monday. && .PRELIMINARY POINT TEMPS/POPS... DDC 72 96 71 92 / 10 10 20 30 GCK 69 97 69 92 / 10 10 10 20 EHA 67 97 68 93 / 10 10 10 20 LBL 69 98 69 93 / 10 10 20 30 HYS 71 96 73 91 / 10 10 10 20 P28 73 95 75 92 / 10 10 20 30 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Sugden LONG TERM...Kruse AVIATION...Burgert
AREA FORECAST DISCUSSION
NWS WICHITA KS
1151 PM CDT SUN JUN 15 2014 ...UPDATED FOR 06Z AVIATION DISCUSSION... .SYNOPSIS... ISSUED AT 330 PM CDT SUN JUN 15 2014 THE OVERNIGHT MCS HAS LEFT A COOLER AND CLOUDY DAY IN IT`S WAKE FOR MUCH OF SOUTHEAST KANSAS. THROUGHOUT THE REST OF KANSAS SKIES ARE CLEAR AND TEMPERATURES ARE IN THE UPPER 70S LOW 80S. BILLINGS WRIGHT && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 330 PM CDT SUN JUN 15 2014 TONIGHT: THE CONCERN FOR SURFACE BASED CONVECTION THIS AFTERNOON IS WANING...AS CLOUDS CONTINUE TO COVER NORTHEAST OKLAHOMA AND SOUTHEAST KANSAS. MIXED LAYER CIN IS AROUND 200 J/KG WITH ONLY 500 J/KG CAPE AS OF 3PM FROM SPC MESO ANALYSIS. THINK THESE CONDITIONS WILL KEEP DAYTIME CONVECTION AT BAY OVER SOUTH CENTRAL AND SOUTHEAST KANSAS. DAYTIME RUNS OF THE HRRR CONTINUE TO KEEP MOST OF THE CONVECTION DURING THE AFTERNOON AND EARLY EVENING HOURS IN OKLAHOMA. HOWEVER...LATER TONIGHT THINGS WILL CHANGE. MOISTURE TRANSPORT WITH THE LOW LEVEL JET WILL INCREASE IN THE LATE EVENING HOURS AND WITH PLENTIFUL ELEVATED INSTABILITY AND SHEAR...STORMS MAY DEVELOP OVER SOUTHEAST KANSAS OR MOVE IN FROM NORTHEAST OKLAHOMA INTO THE AREA. THE MAIN TIME FRAME OF CONCERN WILL BE BETWEEN 10PM- MORNING. THE MAIN THREATS WILL BE THIS CONVECTION WILL BE LARGE HAIL UP TO GOLF BALL SIZED AND GUSTY WINDS TO 60 MPH. MOVE OFF TO THE EAST MY MONDAY MORNING AND AS SKIES CLEAR THE AREA WILL BEGIN TO DRY OUT. MONDAY - WEDNESDAY: MONDAY AND TUESDAY LOOK DRY...WARM AND WINDY. KANSAS WILL SIT UNDER SOUTHWESTERLY UPPER LEVEL FLOW WITH THE GULF WIDE OPEN. AS A SURFACE LOW DEEPENS MONDAY...SOUTHERLY GRADIENT WINDS WILL INCREASE AND PERSIST THROUGH TUESDAY. WINDS WILL BE STRONGER ON MONDAY THAN EXPECTED ON TUESDAY...WITH WINDS APPROACHING THE 30 MPH WIND ADVISORY CRITERIA MONDAY AFTERNOON. HAVE NOT ISSUED A WIND ADVISORY AT THIS TIME...AS FORECAST WINDS ARE JUST SKIRTING THE CRITERIA. TEMPERATURES WILL BE WARM...INTO THE MID TO UPPER 90S MONDAY AND TUESDAY WITH MINIMAL CLOUD COVER. WITH HIGH DEWPOINTS ACROSS THE REGION...HEAT INDEX VALUES MAY APPROACH 100 IN A FEW PLACES. BY WEDNESDAY AFTERNOON/NIGHT THINGS BEGIN TO CHANGE AS THE NEXT UPPER WAVE BEGINS TO APPROACH THE AREA. GUIDANCE INDICATES THUNDERSTORM DEVELOPMENT LATE WEDNESDAY INTO THE OVERNIGHT HOURS IN THE WARM SECTOR AHEAD OF THE NEXT COLD FRONT. BILLINGS WRIGHT .LONG TERM...(THURSDAY THROUGH SUNDAY) ISSUED AT 330 PM CDT SUN JUN 15 2014 THE NEXT FRONT WILL SLIDE THROUGH THURSDAY...BUT THE MAIN UPPER DISTURBANCE ASSOCIATED WITH THE FRONT GETS CUT OFF FROM THE MAIN FLOW AND HOVERS OVER NORTH DAKOTA/CANADA BORDER. THIS PUSHES THE CENTRAL PLAINS INTO MORE OF A ZONAL UPPER PATTERN WITH MULTIPLE DISTURBANCES ROUNDING THE UPPER LOW. BECAUSE OF THIS THE EXTENDED HAS PERIODS OF RAIN THROUGHOUT. RAIN/THUNDERSTORMS WILL NOT OCCUR ALL THE TIME...BUT EXACT TIMING AND PLACEMENT IS DIFFICULT WITH THE DESCREPANCES AMONG THE GUIDANCE. EXPECT AT LEAST SOME PERIODS WITH ADDITIONAL RAINFALL. HIGHS WILL BE IN THE UPPER 80S AND 90S THROUGH THE EXTENDED. BILLINGS WRIGHT && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1149 PM CDT SUN JUN 15 2014 AN ISOLATED SHOWER OR THUNDERSTORM WILL REMAIN POSSIBLE ALONG A SUBTLE WARM FRONT LIFTING NORTH ACROSS SOUTH CENTRAL KANSAS TONIGHT. LOW LEVEL MOISTURE TRANSPORT IS PROGGED TO INCREASE IN RESPONSE TO A SUBTLE LLJ NOSING INTO THE CENTRAL PLAINS THROUGH 07-09Z. AS LOW LEVEL MOISTURE RETURNS NORTH TONIGHT...AREAS OF MVFR CIGS/VISIBILITIES WILL BE POSSIBLE...ESPECIALLY BETWEEN 09-13Z BEFORE VFR RETURNS TO THE AREA. BREEZY SOUTHERLY WINDS WILL INCREASE TO 25 TO 35 KNOTS ACROSS MUCH OF CENTRAL AND SOUTH CENTRAL KANSAS BY LATE MORNING. && .PRELIMINARY POINT TEMPS/POPS... WICHITA-KICT 71 94 74 92 / 20 10 10 10 HUTCHINSON 70 94 74 94 / 20 10 10 10 NEWTON 69 92 73 92 / 20 10 10 10 ELDORADO 69 90 73 90 / 20 10 10 10 WINFIELD-KWLD 71 92 74 90 / 30 10 10 10 RUSSELL 66 96 73 97 / 20 10 10 10 GREAT BEND 67 96 72 96 / 20 10 10 10 SALINA 69 94 75 95 / 20 10 10 10 MCPHERSON 69 93 73 93 / 20 10 10 10 COFFEYVILLE 71 90 73 89 / 50 10 10 10 CHANUTE 70 90 72 89 / 30 10 10 10 IOLA 69 90 72 89 / 30 10 10 10 PARSONS-KPPF 70 89 74 89 / 50 10 10 10 && .ICT WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
205 PM EDT MON JUN 16 2014 .UPDATE... ISSUED AT 205 PM EDT MON JUN 16 2014 LOOKS LIKE THE CU IS GETTING SUFFICIENTLY DEEP TO START PRODUCING SOME RETURNS ON RADAR OVER THE JKL CWA. THE MAIN THREAT WILL STILL BE TO THE NORTH OF INTERSTATE 64 WITH A BIT BETTER SFC FORCING FROM THE APPROACHING FRONT AND LOWER MID LEVEL HEIGHTS...BUT DIFFERENTIAL HEATING ELSEWHERE SHOULD BE ENOUGH FOR ISOALTED TO SCATTERED CONVECTION ACROSS MUCH OF THE AREA LATE THIS AFTERNOON. HAVE FINE TUNED THE GRIDDED FORECAST FOR THIS AND MADE SOME TWEAKS BASED ON CURRENT T/TD/SKY OBS AND TRENDS. THESE HAVE BEEN SENT TO THE NDFD AND WEB SERVERS. UPDATE ISSUED AT 1010 AM EDT MON JUN 16 2014 13Z SFC ANALYSIS SHOWS HIGH PRESSURE HOLDING ON OVER THE SOUTHEAST PORTION OF THE NATION AND LOW PRESSURE TO THE NORTHWEST WHILE A COLD FRONT IS MOVING EAST INTO THE NORTHWEST PORTION OF THE OHIO VALLEY. AS A RESULT OF THIS PATTERN...SOUTHWEST FLOW IS SUPPORTING VERY WARM TEMPERATURES THROUGH EAST KENTUCKY ALONG WITH STEAMY DEWPOINTS. ANY PATCHY FOG THAT WAS OUT THERE EARLIER THIS MORNING HAS BURNED OFF. THERE ARE A FEW SHOWERS AND THUNDERSTORMS MOVING THROUGH SOUTHERN INDIANA ASSOCIATED WITH A WEAKENING MID LEVEL TROUGH AND SOME REMNANT ENERGY...AHEAD OF THAT SFC FRONT. THE HRRR CARRIES THE THREAT FOR SHOWERS AND STORMS INTO OUR NORTHERN COUNTIES THROUGH THE NEXT SEVERAL HOURS ALONG WITH ADDITIONAL CONVECTION DEVELOPING THROUGH THE REST OF THE AREA...POTENTIALLY STARTING OVER OUR HIGHER TERRAIN. THIS MAKES SENSE GIVEN THE SLIGHTLY LOWER 500MB HEIGHTS THIS AFTERNOON AND THE INSTABILITY THAT WILL BE IN PLACE. ACCORDINGLY... HAVE UPDATED THE FORECAST TO ADD A THREAT OF THUNDERSTORMS TO THE ENTIRE FORECAST AREA THROUGHOUT THE DAY...BUT PRIMARILY FOR THE AFTERNOON AND EARLY EVENING HOURS. ALSO ADJUSTED HIGH TEMPERATURES TODAY TOWARD THE CONSSHORT GUIDANCE IN CONJUNCTION WITH THE HIGHS OF YESTERDAY. FINALLY...MESHED THE CURRENT OBS AND TRENDS FOR T/TD/SKY INTO THE GRIDS FOR THE NEXT FEW HOURS. THESE UPDATES HAVE BEEN SENT TO THE NDFD AND WEB SERVERS ALONG WITH FRESHENED ZFP AND HWO. UPDATE ISSUED AT 734 AM EDT MON JUN 16 2014 UPDATED THE FORECAST TO BETTER REFLECT CURRENT CONDITIONS AND MODEL TRENDS. ONLY MADE SOME MINOR TWEAKS TO THE HOURLY TEMPERATURES. THE REST OF THE FORECAST IS ON TRACK. && .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 330 AM EDT MON JUN 16 2014 AT 3AM...A COLD FRONT EXTENDED FROM LAKE MICHIGAN ACROSS ILLINOIS INTO MISSOURI. THE SOUTHERN PORTION OF THIS FRONT WILL BE FALLING APART AS IT APPROACHES THE AREA TODAY. THIS BIG QUESTION IS HOW WILL THE REMNANTS OF THIS FRONT EFFECT THE AREA AS IT MOVES ACROSS EASTERN KENTUCKY TODAY. LOOKING AT THE NAM BUFFER SOUNDINGS FOR THE AREA... THERE IS ENOUGH INSTABILITY IN ORDER TO BE ABLE TO SUSTAIN CONVECTION. AT JACKSON THIS AFTERNOON AT 2 PM...THE LIFTED INDEX VALUES ARE FORECAST TO BE -4 WITH TOTAL TOTALS OF 48. THE LOW LEVEL INSTABILITY IS STRONG AND THERE IS ONLY A HINT OF A MID LEVEL CAP. THE KEY TO TODAY IS TRYING TO FIND ANY TRIGGERS TO GET THE CONVECTION GOING. THE BEST CHANCE FOR SEEING ANYTHING DEVELOP WILL BE NORTH OF I 64 AND ALONG THE VA BORDER. AS A SIDEBAR...SOME CONVECTION MAY MOVE UP FROM TENNESSEE AND SLIDE INTO THE BORDER AREA THIS AFTERNOON. ALTHOUGH NO CONVECTION IS FORECAST FOR A MAJORITY OF THE AREA TODAY...A VERY ISOLATED CELL OR TWO MAY POP UP. THE TEMPERATURES WILL BE EVEN WARMER TODAY THAN YESTERDAY WILL MANY LOCATIONS FLIRTING WITH 90 TODAY. TOMORROW WILL BE A LITTLE COOLED AS SOME OF THE COOLER AIR TO THE NORTH WILL BE MOVING INTO THE AREA. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 330 AM EDT MON JUN 16 2014 STILL QUITE A BIT OF UNCERTAINTY AMONGST THE MODELS FOR THE EXTENDED REGARDING THE OVERALL LARGE SCALE PATTERN...TIMING OF WEATHER SYSTEM PASSAGE ACROSS THE EASTERN THIRD OF THE CONUS...AND THE EVOLUTION...TIMING...AND AREAL COVERAGE OF PRECIPITATION WITH SAID WEATHER SYSTEMS. THAT ALL BEING SAID...THE GENERAL WEATHER PATTERN WILL FEATURE A DIRTY RIDGE OF HIGH PRESSURE SITUATED OVER THE SOUTHEASTERN CONUS TO BEGIN THE PERIOD. UNSTABLE AIR AND MEAGER MOISTURE OFF THE GULF OF MEXICO COULD BRING ISOLATED TO SCATTERED SHOWERS AND STORMS TO EASTERN KENTUCKY AS EARLY AS WEDNESDAY MORNING. THE PATTERN WILL SLOWLY EVOLVE THROUGHOUT THE WEEK AS A FRONTAL BOUNDARY AND A SERIES OF UPPER LEVEL IMPULSES MOVE IN FROM THE NORTH AND THE MOISTURE FLUX OFF THE GULF SLOWLY INCREASES. THE MIDDLE OF THE WEEK COULD FEATURE ISOLATED TO SCATTERED SHOWERS AND STORMS NORTH OF THE HAL ROGERS PARKWAY AND HIGHWAY 80 CORRIDOR. BY FRIDAY NIGHT AND SATURDAY IT APPEARS THAT A COLD FRONT WILL FINALLY MAKE ITS WAY OUT OF THE OHIO VALLEY AND ACROSS THE FORECAST AREA. THE FRIDAY NIGHT THROUGH SUNDAY TIME FRAME WOULD BE THE MOST FAVORED TIME FOR MORE WIDESPREAD SHOWERS AND STORMS...WITH A 40 TO 50 PERCENT CHANCE OF RAIN DURING THE PERIOD. TEMPERATURES THROUGHOUT THE PERIOD WILL BE WELL ABOVE NORMAL WITH READINGS TOPPING OUT IN THE MID TO UPPER 80S WITH OVERNIGHT LOWS RANGING FROM THE MID 60S TO LOWER 70S THROUGHOUT THE PERIOD. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 145 PM EDT MON JUN 16 2014 VFR CONDITIONS WILL STILL DOMINATE THE WX THROUGH THE NEXT 24 TO 36 HOURS. THERE WILL BE A SMALL CHANCE FOR THUNDERSTORMS OVER PARTS OF THE FORECAST AREA OVER THE NEXT FEW HOURS AS A WEAK FRONT BRUSHES BY...BUT CHANCES AT ANY LOCATION WILL BE TOO LOW TO INCLUDE IN THE TAFS...EVEN AS A VCTS. AGAIN EXPECT ANY FOG TO BE CONFINED TO THE DEEPER VALLEYS LATE TONIGHT LEAVING THE TAFS CLEAN. WINDS WILL BE LIGHT THROUGH THE PERIOD...GENERALLY FROM THE SOUTHWEST. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GREIF SHORT TERM...JJ LONG TERM...AR AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1010 AM EDT MON JUN 16 2014 .UPDATE... ISSUED AT 1010 AM EDT MON JUN 16 2014 13Z SFC ANALYSIS SHOWS HIGH PRESSURE HOLDING ON OVER THE SOUTHEAST PORTION OF THE NATION AND LOW PRESSURE TO THE NORTHWEST WHILE A COLD FRONT IS MOVING EAST INTO THE NORTHWEST PORTION OF THE OHIO VALLEY. AS A RESULT OF THIS PATTERN...SOUTHWEST FLOW IS SUPPORTING VERY WARM TEMPERATURES THROUGH EAST KENTUCKY ALONG WITH STEAMY DEWPOINTS. ANY PATCHY FOG THAT WAS OUT THERE EARLIER THIS MORNING HAS BURNED OFF. THERE ARE A FEW SHOWERS AND THUNDERSTORMS MOVING THROUGH SOUTHERN INDIANA ASSOCIATED WITH A WEAKENING MID LEVEL TROUGH AND SOME REMNANT ENERGY...AHEAD OF THAT SFC FRONT. THE HRRR CARRIES THE THREAT FOR SHOWERS AND STORMS INTO OUR NORTHERN COUNTIES THROUGH THE NEXT SEVERAL HOURS ALONG WITH ADDITIONAL CONVECTION DEVELOPING THROUGH THE REST OF THE AREA...POTENTIALLY STARTING OVER OUR HIGHER TERRAIN. THIS MAKES SENSE GIVEN THE SLIGHTLY LOWER 500MB HEIGHTS THIS AFTERNOON AND THE INSTABILITY THAT WILL BE IN PLACE. ACCORDINGLY... HAVE UPDATED THE FORECAST TO ADD A THREAT OF THUNDERSTORMS TO THE ENTIRE FORECAST AREA THROUGHOUT THE DAY...BUT PRIMARILY FOR THE AFTERNOON AND EARLY EVENING HOURS. ALSO ADJUSTED HIGH TEMPERATURES TODAY TOWARD THE CONSSHORT GUIDANCE IN CONJUNCTION WITH THE HIGHS OF YESTERDAY. FINALLY...MESHED THE CURRENT OBS AND TRENDS FOR T/TD/SKY INTO THE GRIDS FOR THE NEXT FEW HOURS. THESE UPDATES HAVE BEEN SENT TO THE NDFD AND WEB SERVERS ALONG WITH FRESHENED ZFP AND HWO. UPDATE ISSUED AT 734 AM EDT MON JUN 16 2014 UPDATED THE FORECAST TO BETTER REFLECT CURRENT CONDITIONS AND MODEL TRENDS. ONLY MADE SOME MINOR TWEAKS TO THE HOURLY TEMPERATURES. THE REST OF THE FORECAST IS ON TRACK. && .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 330 AM EDT MON JUN 16 2014 AT 3AM...A COLD FRONT EXTENDED FROM LAKE MICHIGAN ACROSS ILLINOIS INTO MISSOURI. THE SOUTHERN PORTION OF THIS FRONT WILL BE FALLING APART AS IT APPROACHES THE AREA TODAY. THIS BIG QUESTION IS HOW WILL THE REMNANTS OF THIS FRONT EFFECT THE AREA AS IT MOVES ACROSS EASTERN KENTUCKY TODAY. LOOKING AT THE NAM BUFFER SOUNDINGS FOR THE AREA... THERE IS ENOUGH INSTABILITY IN ORDER TO BE ABLE TO SUSTAIN CONVECTION. AT JACKSON THIS AFTERNOON AT 2 PM...THE LIFTED INDEX VALUES ARE FORECAST TO BE -4 WITH TOTAL TOTALS OF 48. THE LOW LEVEL INSTABILITY IS STRONG AND THERE IS ONLY A HINT OF A MID LEVEL CAP. THE KEY TO TODAY IS TRYING TO FIND ANY TRIGGERS TO GET THE CONVECTION GOING. THE BEST CHANCE FOR SEEING ANYTHING DEVELOP WILL BE NORTH OF I 64 AND ALONG THE VA BORDER. AS A SIDEBAR...SOME CONVECTION MAY MOVE UP FROM TENNESSEE AND SLIDE INTO THE BORDER AREA THIS AFTERNOON. ALTHOUGH NO CONVECTION IS FORECAST FOR A MAJORITY OF THE AREA TODAY...A VERY ISOLATED CELL OR TWO MAY POP UP. THE TEMPERATURES WILL BE EVEN WARMER TODAY THAN YESTERDAY WILL MANY LOCATIONS FLIRTING WITH 90 TODAY. TOMORROW WILL BE A LITTLE COOLED AS SOME OF THE COOLER AIR TO THE NORTH WILL BE MOVING INTO THE AREA. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 330 AM EDT MON JUN 16 2014 STILL QUITE A BIT OF UNCERTAINTY AMONGST THE MODELS FOR THE EXTENDED REGARDING THE OVERALL LARGE SCALE PATTERN...TIMING OF WEATHER SYSTEM PASSAGE ACROSS THE EASTERN THIRD OF THE CONUS...AND THE EVOLUTION...TIMING...AND AREAL COVERAGE OF PRECIPITATION WITH SAID WEATHER SYSTEMS. THAT ALL BEING SAID...THE GENERAL WEATHER PATTERN WILL FEATURE A DIRTY RIDGE OF HIGH PRESSURE SITUATED OVER THE SOUTHEASTERN CONUS TO BEGIN THE PERIOD. UNSTABLE AIR AND MEAGER MOISTURE OFF THE GULF OF MEXICO COULD BRING ISOLATED TO SCATTERED SHOWERS AND STORMS TO EASTERN KENTUCKY AS EARLY AS WEDNESDAY MORNING. THE PATTERN WILL SLOWLY EVOLVE THROUGHOUT THE WEEK AS A FRONTAL BOUNDARY AND A SERIES OF UPPER LEVEL IMPULSES MOVE IN FROM THE NORTH AND THE MOISTURE FLUX OFF THE GULF SLOWLY INCREASES. THE MIDDLE OF THE WEEK COULD FEATURE ISOLATED TO SCATTERED SHOWERS AND STORMS NORTH OF THE HAL ROGERS PARKWAY AND HIGHWAY 80 CORRIDOR. BY FRIDAY NIGHT AND SATURDAY IT APPEARS THAT A COLD FRONT WILL FINALLY MAKE ITS WAY OUT OF THE OHIO VALLEY AND ACROSS THE FORECAST AREA. THE FRIDAY NIGHT THROUGH SUNDAY TIME FRAME WOULD BE THE MOST FAVORED TIME FOR MORE WIDESPREAD SHOWERS AND STORMS...WITH A 40 TO 50 PERCENT CHANCE OF RAIN DURING THE PERIOD. TEMPERATURES THROUGHOUT THE PERIOD WILL BE WELL ABOVE NORMAL WITH READINGS TOPPING OUT IN THE MID TO UPPER 80S WITH OVERNIGHT LOWS RANGING FROM THE MID 60S TO LOWER 70S THROUGHOUT THE PERIOD. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 945 AM EDT MON JUN 16 2014 VFR CONDITIONS WILL DOMINATE THE WX THROUGH THE NEXT 24 HOURS... THERE WILL BE A SMALL CHANCE FOR THUNDERSTORMS OVER PARTS OF THE FORECAST AREA THIS AFTERNOON AS A WEAK FRONT BRUSHES BY...BUT CHANCES AT ANY LOCATION WILL BE TOO LOW TO INCLUDE IN THE TAFS EVEN AS A VCTS. AGAIN EXPECT ANY FOG TO BE CONFINED TO THE DEEPER VALLEYS LATE TONIGHT LEAVING THE TAFS CLEAN. WINDS WILL BE LIGHT THROUGH THE PERIOD...GENERALLY FROM THE SOUTHWEST. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GREIF SHORT TERM...JJ LONG TERM...AR AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS JACKSON KY
734 AM EDT MON JUN 16 2014 .UPDATE... ISSUED AT 734 AM EDT MON JUN 16 2014 UPDATED THE FORECAST TO BETTER REFLECT CURRENT CONDITONS AND MODEL TRENDS. ONLY MADE SOME MINOR TWEAKS TO THE HOURLY TEMPERATURES. THE REST OF THE FORECAST IS ON TRACK. UPDATE ISSUED AT 1130 PM EDT SUN JUN 15 2014 A FEW RENEGADE SHOWERS DEVELOPED AND MOVED INTO MCCREARY COUNTY OVER THE LAST COUPLE OF HOURS...BUT BOTH WERE SMALL BOTH IN INTENSITY AND COVERAGE...AND HAVE SINCE ALMOST COMPLETELY DISSIPATED. ACCORDING TO SATELLITE...A SMALL BAND OF CLOUDS HAVE SET UP ACROSS THE APPALACHIAN REGION JUST SE OF KY. ALONG WITH THIS BAND OF CLOUDS...SOME SPOTTY VERY LIGHT SPRINKLES HAVE FORMED OVER THE LAST HOUR. AT THE CURRENT RADAR AND SATELLITE TREND...EXPECT THESE SPRINKLES TO REMAIN SE OF THE MOUNTAIN RIDGE/STATE LINE DIVIDE CAUSING LITTLE TO NO IMPACT TO OUR CWA OTHER THAN SOME ENHANCED CLOUD COVER OVER BELL THROUGH LETCHER COUNTY. OTHERWISE...FORECAST SEEMS TO BE WELL ON TRACK. ONCE AGAIN...UPDATED THE CURRENT FORECAST WITH THE LATEST OBSERVATIONAL DATA FOR TEMPS...WINDS...AND DEW POINTS...TO MAKE SURE THE ONGOING CONDITIONS ARE REFLECTED IN THE FORECAST. UPDATE ISSUED AT 630 PM EDT SUN JUN 15 2014 SOME ISOLATED PULSY LIGHT SHOWERS ARE CONTINUING TO SHOW UP ON RADAR ACROSS THE SOUTHERN HALF OF THE CWA. AS A RESULT...DECIDED TO INCREASE ISOLATED THUNDER AS WELL AS CHANCES OF SPRINKLES FURTHER NORTHWARD...COVERING MUCH OF THE SOUTH HALF OF THE CWA. STILL EXPECT THESE SHOWERS TO DIE DOWN SHORTLY WITH LOSS OF DAYTIME HEATING...OVER THE NEXT COUPLE OF HOURS. ALSO DECIDED TO UPDATE THE SKY GRIDS TO BETTER REFLECT CURRENT CONDITIONS AND A DIMINISHING TREND INTO THE EVENING. WENT AHEAD AND LOADED IN THE LATEST OBSERVATIONAL GUIDANCE TO MAKE SURE ONGOING GRIDS FOR TEMPS...DEW POINTS...AND WINDS WERE WELL REFLECTIVE OF THE CURRENT CONDITIONS. && .SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT) ISSUED AT 350 PM EDT SUN JUN 15 2014 18Z SFC ANALYSIS SHOWS HIGH PRESSURE EAST OF KENTUCKY WHILE A LARGE AREA OF LOW PRESSURE...CENTERED OVER THE UPPER MIDWEST...IS SLOWLY PUSHING A COLD FRONT THROUGH THE MID MISSISSIPPI VALLEY. THE EXIT OF THE HIGH HAS ALLOWED WARMER AND MORE MOIST AIR TO MOVE BACK INTO EAST KENTUCKY THIS AFTERNOON. TEMPERATURES HAVE CLIMBED INTO THE MIDDLE AND UPPER 80S FOR MOST OF THE AREA UNDER MOSTLY SUNNY SKIES...THOUGH THE SOUTHERN PARTS OF EAST KENTUCKY HAS GONE PARTLY CLOUDY DUE TO SOME HEALTHY CU DEVELOPMENT. DEWPOINTS HAVE COME UP DRAMATICALLY WITH READINGS NOW IN THE MID 60S FOR THE SOUTHERN TWO THIRDS OF THE CWA AND LOW 60S TO THE NORTH. WINDS HAVE BEEN GENERALLY LIGHT FROM THE SOUTHWEST...THOUGH A FEW GUSTS TO 15 KTS HAVE BEEN NOTED OVER THE CUMBERLAND VALLEY RECENTLY. ALSO RECENTLY...SOME LIGHT RETURNS HAVE SHOWN UP ON RADAR OVER THE FAR SOUTHERN PARTS OF THE AREA WHERE SPRINKLES OR A BRIEF LIGHT SHOWER ARE POSSIBLE FOR THE REMAINDER OF THE AFTERNOON. THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM PORTION OF THE FORECAST AS THEY ALL DEPICT THE CONTINUING INFLUENCE OF RIDGING THROUGH THE SOUTHEAST INTO THE FIRST PART OF THE NEW WORK WEEK. A FAIRLY STRONG TROUGH OVER THE UPPER MIDWEST WILL LIFT INTO CENTRAL CANADA...NORTH OF THE GREAT LAKES TONIGHT AN INTO THE DAY MONDAY. AS IT DOES SO...ITS SOUTHERN EXTENT WILL QUICKLY WEAKEN... BUT NOT BEFORE DRAGGING THE REMAINS OF SOME ENERGY ASSOCIATED WITH ITS TROUGH AXIS THROUGH THE OHIO VALLEY. THIS WILL HELP TO SLIGHTLY LOWER HEIGHTS LOCALLY INTO THE DAY MONDAY...MAINLY OVER NORTHERN PARTS OF THE AREA. HEIGHTS WILL REBOUND AND STRENGTHEN THROUGH THE REST OF THE DAY AND INTO TUESDAY MORNING AS THE STORM TRACK IS SHUNTED EVEN FURTHER NORTH. DUE TO GOOD MODEL AGREEMENT HAVE GONE WITH A BLENDED SOLUTION WITH PARTICULAR EMPHASIS ON THE HIGHER RESOLUTION HRRR AND NAM12 FOR THE FIRST 24 HOURS. SENSIBLE WEATHER WILL FEATURE SOME SPRINKLES AND A STRAY SHOWER AROUND THE CUMBERLAND VALLEY INTO THE FIRST PART OF THE EVENING BEFORE EVERYTHING CLEARS OUT INCLUDING THE BULK OF THE CU. THIS WILL SET UP ANOTHER NIGHT OF RADIATIONAL COOLING INDUCED RIDGE TO VALLEY TEMPERATURE DIFFERENCES...THOUGH LIMITED SOMEWHAT BY THE HIGHER DEWPOINTS. WILL ALSO LIKELY SEE A BIT MORE IN THE WAY OF VALLEY FOG LATE TONIGHT WITH MOSTLY CLEAR SKIES...LIGHT WINDS...AND DEWPOINTS SIGNIFICANTLY HIGHER THAN LAST NIGHT. FOR MONDAY...THE REMAINS OF THE 500MB TROUGH...SLIGHTLY LOWER HEIGHTS...AND A WEAKENING FRONT SHOULD BE ENOUGH TO KICK OFF A COUPLE SHOWERS AND THUNDERSTORMS BY MIDDAY... MAINLY IN OUR NORTHERN ZONES. ANY CONVECTION SHOULD DIE OFF BY EVENING AS RIDGING BUILDS ALOFT...INTO THE EVENING. MORE IN THE WAY OF CLOUDS ON MONDAY NIGHT SHOULD KEEP THE RIDGE AND VALLEY TEMPERATURE DIFFERENCES IN THE SMALL CATEGORY ALONG WITH ANY FOG CONFINED TO JUST THE DEEPER RIVER VALLEYS. ONCE AGAIN STARTED WITH THE BCCONSSHORT FOR T/TD AND WINDS THROUGH MIDDAY MONDAY BEFORE CONTINUING WITH BCCONSALL. DID MAKE SOME ADJUSTMENTS TO THE VALLEY AND RIDGE TEMPERATURES TONIGHT AND TO A LESSER EXTENT MONDAY NIGHT...DUE TO SOME RADIATIONAL COOLING. FOR POPS...ENDED UP MOST SIMILAR TO THE WETTER MET NUMBERS MONDAY AFTERNOON...OTHERWISE KEPT THEM LOW. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 334 AM EDT MON JUN 16 2014 STILL QUITE A BIT OF UNCERTAINTY AMONGST THE MODELS FOR THE EXTENDED REGARDING THE OVEALL LARGE SCALE PATTERN...TIMING OF WEATHER SYSTEM PASSAGE ACROSS THE EASTERN THIRD OF THE CONUS...AND THE EVOLUTION...TIMING...AND AREAL COVERAGE OF PRECIPITATION WITH SAID WEATHER SYSTEMS. THAT ALL BEING SAID...THE GENERAL WEATHER PATTERN WILL FEATURE A DIRTY RIDGE OF HIGH PRESSURE SITUATED OVER THE SOUTHEASTERN CONUS TO BEGIN THE PERIOD. UNSTABLE AIR AND MEAGER MOISTURE OFF THE GULF OF MEXICO COULD BRING ISOLATED TO SCATTERED SHOWERS AND STORMS TO EASTERN KENTUCKY AS EARLY AS WEDNESDAY MORNING. THE PATTERN WILL SLOWLY EVOLVE THROUGHOUT THE WEEK AS A FRONTAL BOUNDARY AND A SERIES OF UPPER LEVEL IMPULSES MOVE IN FROM THE NORTH AND THE MOISTURE FLUX OFF THE GULF SLOWLY INCREASES. THE MIDDLE OF THE WEEK COULD FEATURE ISOLATED TO SCATTERED SHOWERS AND STORMS NORTH OF THE HAL ROGERS PARKWAY AND HIGHWAY 80 CORRIDOR. BY FRIDAY NIGHT AND SATURDAY IT APPEARS THAT A COLD FRONT WILL FINALLY MAKE ITS WAY OUT OF THE OHIO VALLEY AND ACROSS THE FORECAST AREA. THE FRIDAY NIGHT THROUGH SUNDAY TIME FRAME WOULD BE THE MOST FAVORED TIME FOR MORE WIDESPREAD SHOWERS AND STORMS...WITH A 40 TO 50 PERCENT CHANCE OF RAIN DURING THE PERIOD. TEMPERATURES THROUGHOUT THE PERIOD WILL BE WELL ABOVE NORMAL WITH READINGS TOPPING OUT IN THE MID TO UPPER 80S WITH OVERNIGHT LOWS RANGING FROM THE MID 60S TO LOWER 70S THROUGHOUT THE PERIOD. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING) ISSUED AT 753 PM EDT SUN JUN 15 2014 WHILE VFR CONDITIONS WILL DOMINATE THE WX THROUGH THE NEXT 24 HOURS...THERE WILL BE A CHANCE FOR A THUNDERSTORM OR TWO OVER NORTHERN PARTS OF THE CWA ON MONDAY AFTERNOON AS A FRONT BRUSHES BY. HAVE ADDED A PREVAILING VCTS FOR THIS FROM EARLY AFTERNOON ON AT JKL AND SJS WHILE LEAVING OUT OF THE OTHER SITES FOR NOW. EXPECT ANY FOG TONIGHT TO BE CONFINED TO THE DEEPER VALLEYS AND LEAVE THE TAF SITES UNBLEMISHED. WINDS WILL BE LIGHT THROUGH THE PERIOD...GENERALLY FROM THE SOUTHWEST. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...JJ SHORT TERM...GREIF LONG TERM...AR AVIATION...GREIF/JMW
AREA FORECAST DISCUSSION
NWS JACKSON KY
334 AM EDT MON JUN 16 2014 .UPDATE... ISSUED AT 1130 PM EDT SUN JUN 15 2014 A FEW RENEGADE SHOWERS DEVELOPED AND MOVED INTO MCCREARY COUNTY OVER THE LAST COUPLE OF HOURS...BUT BOTH WERE SMALL BOTH IN INTENSITY AND COVERAGE...AND HAVE SINCE ALMOST COMPLETELY DISSIPATED. ACCORDING TO SATELLITE...A SMALL BAND OF CLOUDS HAVE SET UP ACROSS THE APPALACHIAN REGION JUST SE OF KY. ALONG WITH THIS BAND OF CLOUDS...SOME SPOTTY VERY LIGHT SPRINKLES HAVE FORMED OVER THE LAST HOUR. AT THE CURRENT RADAR AND SATELLITE TREND...EXPECT THESE SPRINKLES TO REMAIN SE OF THE MOUNTAIN RIDGE/STATE LINE DIVIDE CAUSING LITTLE TO NO IMPACT TO OUR CWA OTHER THAN SOME ENHANCED CLOUD COVER OVER BELL THROUGH LETCHER COUNTY. OTHERWISE...FORECAST SEEMS TO BE WELL ON TRACK. ONCE AGAIN...UPDATED THE CURRENT FORECAST WITH THE LATEST OBSERVATIONAL DATA FOR TEMPS...WINDS...AND DEW POINTS...TO MAKE SURE THE ONGOING CONDITIONS ARE REFLECTED IN THE FORECAST. UPDATE ISSUED AT 630 PM EDT SUN JUN 15 2014 SOME ISOLATED PULSY LIGHT SHOWERS ARE CONTINUING TO SHOW UP ON RADAR ACROSS THE SOUTHERN HALF OF THE CWA. AS A RESULT...DECIDED TO INCREASE ISOLATED THUNDER AS WELL AS CHANCES OF SPRINKLES FURTHER NORTHWARD...COVERING MUCH OF THE SOUTH HALF OF THE CWA. STILL EXPECT THESE SHOWERS TO DIE DOWN SHORTLY WITH LOSS OF DAYTIME HEATING...OVER THE NEXT COUPLE OF HOURS. ALSO DECIDED TO UPDATE THE SKY GRIDS TO BETTER REFLECT CURRENT CONDITIONS AND A DIMINISHING TREND INTO THE EVENING. WENT AHEAD AND LOADED IN THE LATEST OBSERVATIONAL GUIDANCE TO MAKE SURE ONGOING GRIDS FOR TEMPS...DEW POINTS...AND WINDS WERE WELL REFLECTIVE OF THE CURRENT CONDITIONS. && .SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT) ISSUED AT 350 PM EDT SUN JUN 15 2014 18Z SFC ANALYSIS SHOWS HIGH PRESSURE EAST OF KENTUCKY WHILE A LARGE AREA OF LOW PRESSURE...CENTERED OVER THE UPPER MIDWEST...IS SLOWLY PUSHING A COLD FRONT THROUGH THE MID MISSISSIPPI VALLEY. THE EXIT OF THE HIGH HAS ALLOWED WARMER AND MORE MOIST AIR TO MOVE BACK INTO EAST KENTUCKY THIS AFTERNOON. TEMPERATURES HAVE CLIMBED INTO THE MIDDLE AND UPPER 80S FOR MOST OF THE AREA UNDER MOSTLY SUNNY SKIES...THOUGH THE SOUTHERN PARTS OF EAST KENTUCKY HAS GONE PARTLY CLOUDY DUE TO SOME HEALTHY CU DEVELOPMENT. DEWPOINTS HAVE COME UP DRAMATICALLY WITH READINGS NOW IN THE MID 60S FOR THE SOUTHERN TWO THIRDS OF THE CWA AND LOW 60S TO THE NORTH. WINDS HAVE BEEN GENERALLY LIGHT FROM THE SOUTHWEST...THOUGH A FEW GUSTS TO 15 KTS HAVE BEEN NOTED OVER THE CUMBERLAND VALLEY RECENTLY. ALSO RECENTLY...SOME LIGHT RETURNS HAVE SHOWN UP ON RADAR OVER THE FAR SOUTHERN PARTS OF THE AREA WHERE SPRINKLES OR A BRIEF LIGHT SHOWER ARE POSSIBLE FOR THE REMAINDER OF THE AFTERNOON. THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM PORTION OF THE FORECAST AS THEY ALL DEPICT THE CONTINUING INFLUENCE OF RIDGING THROUGH THE SOUTHEAST INTO THE FIRST PART OF THE NEW WORK WEEK. A FAIRLY STRONG TROUGH OVER THE UPPER MIDWEST WILL LIFT INTO CENTRAL CANADA...NORTH OF THE GREAT LAKES TONIGHT AN INTO THE DAY MONDAY. AS IT DOES SO...ITS SOUTHERN EXTENT WILL QUICKLY WEAKEN... BUT NOT BEFORE DRAGGING THE REMAINS OF SOME ENERGY ASSOCIATED WITH ITS TROUGH AXIS THROUGH THE OHIO VALLEY. THIS WILL HELP TO SLIGHTLY LOWER HEIGHTS LOCALLY INTO THE DAY MONDAY...MAINLY OVER NORTHERN PARTS OF THE AREA. HEIGHTS WILL REBOUND AND STRENGTHEN THROUGH THE REST OF THE DAY AND INTO TUESDAY MORNING AS THE STORM TRACK IS SHUNTED EVEN FURTHER NORTH. DUE TO GOOD MODEL AGREEMENT HAVE GONE WITH A BLENDED SOLUTION WITH PARTICULAR EMPHASIS ON THE HIGHER RESOLUTION HRRR AND NAM12 FOR THE FIRST 24 HOURS. SENSIBLE WEATHER WILL FEATURE SOME SPRINKLES AND A STRAY SHOWER AROUND THE CUMBERLAND VALLEY INTO THE FIRST PART OF THE EVENING BEFORE EVERYTHING CLEARS OUT INCLUDING THE BULK OF THE CU. THIS WILL SET UP ANOTHER NIGHT OF RADIATIONAL COOLING INDUCED RIDGE TO VALLEY TEMPERATURE DIFFERENCES...THOUGH LIMITED SOMEWHAT BY THE HIGHER DEWPOINTS. WILL ALSO LIKELY SEE A BIT MORE IN THE WAY OF VALLEY FOG LATE TONIGHT WITH MOSTLY CLEAR SKIES...LIGHT WINDS...AND DEWPOINTS SIGNIFICANTLY HIGHER THAN LAST NIGHT. FOR MONDAY...THE REMAINS OF THE 500MB TROUGH...SLIGHTLY LOWER HEIGHTS...AND A WEAKENING FRONT SHOULD BE ENOUGH TO KICK OFF A COUPLE SHOWERS AND THUNDERSTORMS BY MIDDAY... MAINLY IN OUR NORTHERN ZONES. ANY CONVECTION SHOULD DIE OFF BY EVENING AS RIDGING BUILDS ALOFT...INTO THE EVENING. MORE IN THE WAY OF CLOUDS ON MONDAY NIGHT SHOULD KEEP THE RIDGE AND VALLEY TEMPERATURE DIFFERENCES IN THE SMALL CATEGORY ALONG WITH ANY FOG CONFINED TO JUST THE DEEPER RIVER VALLEYS. ONCE AGAIN STARTED WITH THE BCCONSSHORT FOR T/TD AND WINDS THROUGH MIDDAY MONDAY BEFORE CONTINUING WITH BCCONSALL. DID MAKE SOME ADJUSTMENTS TO THE VALLEY AND RIDGE TEMPERATURES TONIGHT AND TO A LESSER EXTENT MONDAY NIGHT...DUE TO SOME RADIATIONAL COOLING. FOR POPS...ENDED UP MOST SIMILAR TO THE WETTER MET NUMBERS MONDAY AFTERNOON...OTHERWISE KEPT THEM LOW. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 334 AM EDT MON JUN 16 2014 STILL QUITE A BIT OF UNCERTAINTY AMONGST THE MODELS FOR THE EXTENDED REGARDING THE OVEALL LARGE SCALE PATTERN...TIMING OF WEATHER SYSTEM PASSAGE ACROSS THE EASTERN THIRD OF THE CONUS...AND THE EVOLUTION...TIMING...AND AREAL COVERAGE OF PRECIPITATION WITH SAID WEATHER SYSTEMS. THAT ALL BEING SAID...THE GENERAL WEATHER PATTERN WILL FEATURE A DIRTY RIDGE OF HIGH PRESSURE SITUATED OVER THE SOUTHEASTERN CONUS TO BEGIN THE PERIOD. UNSTABLE AIR AND MEAGER MOISTURE OFF THE GULF OF MEXICO COULD BRING ISOLATED TO SCATTERED SHOWERS AND STORMS TO EASTERN KENTUCKY AS EARLY AS WEDNESDAY MORNING. THE PATTERN WILL SLOWLY EVOLVE THROUGHOUT THE WEEK AS A FRONTAL BOUNDARY AND A SERIES OF UPPER LEVEL IMPULSES MOVE IN FROM THE NORTH AND THE MOISTURE FLUX OFF THE GULF SLOWLY INCREASES. THE MIDDLE OF THE WEEK COULD FEATURE ISOLATED TO SCATTERED SHOWERS AND STORMS NORTH OF THE HAL ROGERS PARKWAY AND HIGHWAY 80 CORRIDOR. BY FRIDAY NIGHT AND SATURDAY IT APPEARS THAT A COLD FRONT WILL FINALLY MAKE ITS WAY OUT OF THE OHIO VALLEY AND ACROSS THE FORECAST AREA. THE FRIDAY NIGHT THROUGH SUNDAY TIME FRAME WOULD BE THE MOST FAVORED TIME FOR MORE WIDESPREAD SHOWERS AND STORMS...WITH A 40 TO 50 PERCENT CHANCE OF RAIN DURING THE PERIOD. TEMPERATURES THROUGHOUT THE PERIOD WILL BE WELL ABOVE NORMAL WITH READINGS TOPPING OUT IN THE MID TO UPPER 80S WITH OVERNIGHT LOWS RANGING FROM THE MID 60S TO LOWER 70S THROUGHOUT THE PERIOD. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING) ISSUED AT 753 PM EDT SUN JUN 15 2014 WHILE VFR CONDITIONS WILL DOMINATE THE WX THROUGH THE NEXT 24 HOURS...THERE WILL BE A CHANCE FOR A THUNDERSTORM OR TWO OVER NORTHERN PARTS OF THE CWA ON MONDAY AFTERNOON AS A FRONT BRUSHES BY. HAVE ADDED A PREVAILING VCTS FOR THIS FROM EARLY AFTERNOON ON AT JKL AND SJS WHILE LEAVING OUT OF THE OTHER SITES FOR NOW. EXPECT ANY FOG TONIGHT TO BE CONFINED TO THE DEEPER VALLEYS AND LEAVE THE TAF SITES UNBLEMISHED. WINDS WILL BE LIGHT THROUGH THE PERIOD...GENERALLY FROM THE SOUTHWEST. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...JMW SHORT TERM...GREIF LONG TERM...AR AVIATION...GREIF/JMW
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
146 PM CDT MON JUN 16 2014 .DISCUSSION... 16/18Z TAF ISSUANCE. && .AVIATION... SCT SHRA AND ISO TSRA HAVE DEVELOPED EARLY THIS AFTN MAINLY NORTH OF I-10. LEFT VCSH OR VCTS IN TAFS FOR THE AFTN BUT BASED ON RECENT RADAR TRENDS...HAVE OPTED TO REMOVE TEMPO GROUPS FM SRN TAF SITES AND INSERT ONE AT KAEX. OTHERWISE...EXPECT VFR CONDITIONS TO PREVAIL WITH SLY WINDS AROUND 10 KT THIS AFTN TAPERING DOWN TO AROUND 5 KT OVERNIGHT. SOME SCT LOW CLOUDS EXPECTED TO RETURN AFTER DAYBREAK TUES. 24 && .PREV DISCUSSION... /ISSUED 1103 AM CDT MON JUN 16 2014/ DISCUSSION... MORNING VIS SATELLITE SHOWS A WEAK CU FIELD DEVELOPED NORTH OF A BOUNDARY AT THE COASTLINE. ALONG THAT BOUNDARY SOME POPCORN SHOWERS HAVE DEVELOPED JUST NORTH OF I-10. USED THE HRRR TO INCREASE THE POPS JUST SLIGHTLY OVER THE THE AREA WITH A RUC BACKGROUND. TEMPS ARE ON TRACK TO HEAT UP TO THE HIGH 80S LOW 90S. REST OF FORECAST LOOKS ON TRACK AND SHOULD BE GOOD TO GO. PFM IS SENT AND NO NEW ZFP NEEDED. RDEAL PREV DISCUSSION... /ISSUED 626 AM CDT MON JUN 16 2014/ AVIATION... A MIDTROPOSPHERE TROUGH OF LOW PRESSURE EXTENDS FROM NORTHERN ALABAMA THROUGH THE MOUTH OF THE SABINE RIVER. THE TROUGH WILL MOVE LITTLE THROUGH THIS AFTERNOON...BEFORE FILLING THIS EVENING. SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED ALONG AND SOUTH OF THE I-10 CORRIDOR FROM LAKE CHARLES THROUGH BATON ROUGE. ISOLATED SHOWERS AND THUNDERSTORMS ARE EXPECTED ELSEWHERE. JT PREV DISCUSSION... /ISSUED 258 AM CDT MON JUN 16 2014/ DISCUSSION...SATELLITE IMAGERY DEPICTING SOME STRATOCU OVER CENTRAL LOUISIANA INTO INTERIOR SOUTHEAST TEXAS...AND OFF THE COAST OF LOWER ACADIANA. CLEAR SKIES ELSEWHERE. RADAR CURRENTLY ABSENT OF ANY PRECIP. LIMITED CHANGES TO FORECAST. PATTERN THROUGH THE WEEK WILL BE DICTATED BY DRY HIGH PRESSURE ALOFT MEANDERING ABOUT THE SOUTHEAST CONUS AND THROUGH THE LOWER MISSISSIPPI VALLEY. APPRECIABLE MOISTURE WILL REMAIN CONFINED TO THE LOWER LEVELS...850 MB AND BELOW...LIMITING OUR RAIN CHANCES. MAINTAINING LOW END POPS FOR MAINLY ISOLATED AFTERNOON CONVECTION...AND THIS PRIMARILY ASSOCIATED WITH DIURNAL DEVELOPING SEA BREEZE. OTHERWISE TEMPERATURES WILL REMAIN AT...OR POSSIBLY A DEGREE OR TWO ABOVE THE SEASONAL NORM. MARINE...SURFACE HIGH PRESSURE RIDGING WEST THROUGH THE SOUTHEAST CONUS AND GULF WATERS WILL MAINTAIN A LIGHT TO MODERATE ONSHORE FLOW THROUGH THE WEEK. WITH DRY HIGH PRESSURE ALOFT OVER THE REGION RAIN CHANCES WILL REMAIN LIMITED. 23 && .PRELIMINARY POINT TEMPS/POPS... KLCH 90 74 90 73 / 30 20 20 10 KBPT 90 76 91 76 / 30 20 20 10 KAEX 91 72 91 73 / 30 20 20 10 KLFT 90 75 90 74 / 30 20 20 10 && .LCH WATCHES/WARNINGS/ADVISORIES... LA...NONE. TX...NONE. GM...NONE. && $$
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
1103 AM CDT MON JUN 16 2014 .DISCUSSION... MORNING VIS SATELLITE SHOWS A WEAK CU FIELD DEVELOPED NORTH OF A BOUNDARY AT THE COASTLINE. ALONG THAT BOUNDARY SOME POPCORN SHOWERS HAVE DEVELOPED JUST NORTH OF I-10. USED THE HRRR TO INCREASE THE POPS JUST SLIGHTLY OVER THE THE AREA WITH A RUC BACKGROUND. TEMPS ARE ON TRACK TO HEAT UP TO THE HIGH 80S LOW 90S. REST OF FORECAST LOOKS ON TRACK AND SHOULD BE GOOD TO GO. PFM IS SENT AND NO NEW ZFP NEEDED. RDEAL && .PREV DISCUSSION... /ISSUED 626 AM CDT MON JUN 16 2014/ AVIATION... A MIDTROPOSPHERE TROUGH OF LOW PRESSURE EXTENDS FROM NORTHERN ALABAMA THROUGH THE MOUTH OF THE SABINE RIVER. THE TROUGH WILL MOVE LITTLE THROUGH THIS AFTERNOON...BEFORE FILLING THIS EVENING. SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED ALONG AND SOUTH OF THE I-10 CORRIDOR FROM LAKE CHARLES THROUGH BATON ROUGE. ISOLATED SHOWERS AND THUNDERSTORMS ARE EXPECTED ELSEWHERE. JT PREV DISCUSSION... /ISSUED 258 AM CDT MON JUN 16 2014/ DISCUSSION...SATELLITE IMAGERY DEPICTING SOME STRATOCU OVER CENTRAL LOUISIANA INTO INTERIOR SOUTHEAST TEXAS...AND OFF THE COAST OF LOWER ACADIANA. CLEAR SKIES ELSEWHERE. RADAR CURRENTLY ABSENT OF ANY PRECIP. LIMITED CHANGES TO FORECAST. PATTERN THROUGH THE WEEK WILL BE DICTATED BY DRY HIGH PRESSURE ALOFT MEANDERING ABOUT THE SOUTHEAST CONUS AND THROUGH THE LOWER MISSISSIPPI VALLEY. APPRECIABLE MOISTURE WILL REMAIN CONFINED TO THE LOWER LEVELS...850 MB AND BELOW...LIMITING OUR RAIN CHANCES. MAINTAINING LOW END POPS FOR MAINLY ISOLATED AFTERNOON CONVECTION...AND THIS PRIMARILY ASSOCIATED WITH DIURNAL DEVELOPING SEA BREEZE. OTHERWISE TEMPERATURES WILL REMAIN AT...OR POSSIBLY A DEGREE OR TWO ABOVE THE SEASONAL NORM. MARINE...SURFACE HIGH PRESSURE RIDGING WEST THROUGH THE SOUTHEAST CONUS AND GULF WATERS WILL MAINTAIN A LIGHT TO MODERATE ONSHORE FLOW THROUGH THE WEEK. WITH DRY HIGH PRESSURE ALOFT OVER THE REGION .RAIN CHANCES WILL REMAIN LIMITED. && .PRELIMINARY POINT TEMPS/POPS... KLCH 89 75 91 75 91 / 30 10 20 10 20 KBPT 90 76 91 76 91 / 20 10 20 10 20 KAEX 91 72 91 73 91 / 30 10 20 10 20 KLFT 90 75 90 74 90 / 20 10 20 10 20 && .LCH WATCHES/WARNINGS/ADVISORIES... LA...NONE. TX...NONE. GM...NONE. && FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.LAKECHARLES.GOV WWW.TWITTER.COM/NWSLAKECHARLES WWW.YOUTUBE.COM/NWSLAKECHARLES && $$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
734 PM EDT TUE JUN 17 2014 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 345 PM EDT TUE JUN 17 2014 WATER VAPOR IMAGERY AND RUC ANALYSIS INDICATE THAT THE SHORTWAVE RESPONSIBLE FOR LAST NIGHT/S AND THIS MORNING/S CONVECTION HAS PASSED EAST. BEHIND THE SHORTWAVE...RISING 5H RIDGE HGTS AND ASSOC INCREASED SUBSIDENCE AND Q-VECT DIVERGENCE FROM THE WEST LED TO CLEARING SKIES OVER THE WEST HALF OF THE CWA THIS MORNING AND OVER MUCH OF THE EAST HALF THIS AFTERNOON. MIXING 850 MB TEMPS OF 16-17C TO THE SFC YIELDED INLAND HIGH TEMPS IN THE LOWER TO MID 80S OVER THE INTERIOR WEST HALF OF UPPER MI THIS AFTERNOON. LAKE BREEZES HAVE KEPT TEMPS COOLER NEAR THE SHORELINES...GENERALLY IN THE 60S. MODIFIED RUC SNDGS OVER SCNTRL UPPER MI FOR 86/59 YIELD AROUND 800 J/KG. GIVEN THE INSTABILITY PERHAPS SOME CONVECTION COULD BE INITIATED ALONG DEVELOPING LAKE BREEZE BOUNDARIES OVER SCNTRL WI SO WILL CONTINUE TO CARRY SLIGHT CHC POPS INTO THE EVENING HRS. ANOTHER SHORTWAVE OVER ERN NE IS EXPECTED TO MOVE THROUGH SRN/CNTRL WI TONIGHT ALONG AND NORTH OF WARM FRONT. THIS SHORTWAVE WORKING ON AN ENVIRONMENT OF 1500-2500 J/KG WILL TRIGGER ANOTHER AROUND OF CONVECTION ACROSS WI INTO LOWER MI TONIGHT. MODELS INDICATE THAT THE NRN FRINGE OF THIS CONVECTION MAY BRUSH SCNTRL UPR MI MAINLY SRN MNM COUNTY WITH SOME SHRA/TSRA WHERE THERE REMAINS A FEW HUNDRED J/KG OF INSTABILITY. WILL CONTINUE TO CARRY SLIGHT CHC POPS TONIGHT FOR THIS POSSIBILITY BUT BEST CONVECTION SHOULD STAY WELL SOUTH CLOSER TO WARM FRONT AND BETTER INSTABILITY. INCREASINGLY CONFLUENT FLOW ALOFT AHEAD OF THE NRN PLAINS RIDGE INTO THE UPPER GREAT LAKES LATE TONIGHT INTO WEDNESDAY WILL CONTINUE TO ALLOW SFC RDGG FM HUDSON BAY HIGH TO WORK INTO THE UPPER GREAT LAKES. THIS SHOULD ENSURE MOSTLY DRY CONDITIONS ACROSS THE AREA ON WEDNESDAY. EXPECT SLIGHTLY COOLER HIGHS FROM UPPER 70S TO AROUND 80 INLAND WITH COOLER 60S TO LOWER 70S READINGS NEAR THE GREAT LAKES SHORELINES. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 329 PM EDT TUE JUN 17 2014 TWO UPPER TROUGHS WILL BE SURROUNDING THE UPPER GREAT LAKES REGION (ONE OVER THE NORTHERN ROCKIES AND THE OTHER FAR NORTHERN QUEBEC) TO START THE PERIOD...WITH ASSOCIATED SURFACE LOWS TO THE SOUTHEAST OF THE UPPER TROUGHS. OVER THE UPPER GREAT LAKES REGION...AN UPPER RIDGE AXIS WILL BE CENTERED OVER THE AREA...STRETCHING FROM THE OHIO RIVER VALLEY TO JUST WEST OF HUDSON BAY. A HUDSON BAY HIGH WILL BE ASSOCIATED WITH THIS RIDGE AND STRETCHING A SURFACE RIDGE SOUTH OVER EASTERN LAKE SUPERIOR AND LAKE HURON. THIS UPPER AND SURFACE RIDGE WILL GRADUALLY SHIFT EAST WEDNESDAY NIGHT THROUGH THURSDAY NIGHT...ALLOWING THE SHOWERS AND THUNDERSTORMS TO THE WEST OF THE AREA TO SHIFT FROM WEST TO EAST ACROSS THE CWA DURING THAT TIME. WILL KEEP THE SLIGHT CHANCE POPS THAT ARE RIGHT ALONG THE WISCONSIN BORDER WEDNESDAY NIGHT INTO THURSDAY MORNING...JUST IN CASE CONVECTION THAT FIRES CLOSER TO THE BETTER WARM AIR ADVECTION IN MINNESOTA BRUSHES THAT AREA AS IT MOVES SOUTHEAST. OTHERWISE...THE REST OF THE AREA WILL BE DRY WEDNESDAY NIGHT. WITH THE HUDSON BAY HIGH IN PLACE OVER THE EASTERN HALF OF THE CWA ON THURSDAY...EXPECT THE DRY EASTERLY FLOW TO TRY AND HOLD OFF ANY CONVECTION DEVELOPMENT OVER THE AREA FOR THURSDAY. THE BEST OPPORTUNITY WILL COME OVER THE FAR WEST TOWARDS THE LATER PART OF THE AFTERNOON...AS THE NEXT ROUND OF CONVECTION DEVELOPS IN MINNESOTA ON THURSDAY. WITH PROPAGATION VECTORS POINTING TO THE EAST-SOUTHEAST FROM CENTRAL/NORTHERN MINNESOTA...WOULD EXPECT ANY CONVECTION IN THAT AREA TO MOVE OVER WESTERN UPPER MICHIGAN THURSDAY EVENING. THOSE SHOWERS AND THUNDERSTORMS WOULD CONTINUE TO THE EAST THROUGH THE NIGHT...AIDED BY THE BROAD WARM AIR ADVECTION MOVING EASTWARD IN RESPONSE TO THE UPPER TROUGH LIFTING INTO THE NORTHERN PLAINS AND NORTHWEST MINNESOTA. THIS WILL SUPPORT SCATTERED SHOWERS AND SOME WEAK THUNDERSTORMS (MARGINAL INSTABILITY DUE TO WEAKENING MID LEVEL LAPSE RATES) OVER THE AREA ON FRIDAY (ESPECIALLY WEST/CENTRAL IN THE MORNING). WITH THE BROAD/WEAKENING WAA CONTINUING EAST LATER FRIDAY AFTERNOON INTO FRIDAY NIGHT...EXPECT A PERIOD OF NO PRECIP OVER PORTIONS OF THE AREA AS THE UPPER TROUGH TO THE WEST MERGES WITH THE EASTERN UPPER TROUGH. THIS MERGING OF THE UPPER TROUGHS WILL PULL THE LEFT OVER UPPER WAVE AND WEAK SURFACE LOW SOUTHEAST ACROSS THE UPPER GREAT LAKES REGION THIS WEEKEND. THERE CONTINUES TO BE SOME DIFFERENCES ON THE MERGING OF THE TROUGHS AND HOW QUICKLY IT SWEEPS THROUGH... BUT IT DOES APPEAR THAT THERE WILL BE A PERIOD OF STEADIER RAIN MOVING THROUGH THE AREA AT SOME POINT THIS WEEKEND. THE UPPER TROUGH WILL SLIDE SOUTHEAST ON SUNDAY NIGHT AND ALLOW AN UPPER RIDGE FROM THE NORTHERN PLAINS AND CENTRAL CANADA TO MOVE SOUTHEAST INTO THE AREA AND PRODUCE CLEARING SKIES AND SEASONABLE TEMPERATURES. ALSO NEED TO POINT OUT THAT THE DRY EASTERLY FLOW ON THURSDAY AND A MOSTLY SUNNY SKY WILL ALLOW FOR DEEP MIXING AND RH VALUES FALLING TOWARDS 20-25 PERCENT OVER THE EASTERN THIRD OF THE CWA. LIGHT RAINS IN THAT AREA DURING THE LAST 2 DAYS HAS IMPROVED FFMC VALUES...BUT DRY CONDITIONS TODAY AND WEDNESDAY SHOULD ALLOW THE FINE FUELS TO DRY BACK OUT BY THURSDAY. FORTUNATELY...WIND GUSTS SHOULD ONLY BE IN THE 10-20MPH RANGE ON THURSDAY AND LIMIT THE WILDFIRE CONCERNS. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING) ISSUED AT 733 PM EDT TUE JUN 17 2014 VFR CONDITIONS SHOULD PREVAIL AT KIWD/KCMX/KSAW THROUGH THIS FCST PERIOD AS LOW-LEVELS REMAIN RELATIVELY DRY UNDER DOMINANT HIGH PRESSURE. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 345 PM EDT TUE JUN 17 2014 LINGERING HIGH DEWPOINTS ACROSS THE AREA WILL WARRANT MENTION OF PATCHY FOG OVER THE WEST INTO WEDNESDAY AND AREAS OF FOG OVER THE EAST HALF OF THE LAKE. SHIP REPORTS AND WEB CAMS CONFIRM THAT MUCH OF THE FOG OVER THE EAST HALF IS DENSE SO HAVE ISSUED A DENSE FOG ADVISORY THROUGH WED MORNING. A TROUGH OF LOW PRESSURE OVER LAKE SUPERIOR TODAY WILL BE SLOWLY REPLACED BY A RIDGE THIS EVENING...EXTENDING FROM HIGH PRESSURE ACROSS SOUTHERN HUDSON BAY AND NORTHERN ONTARIO. LIGHT WINDS WILL BECOME NE...AND FUNNEL OVER THE W HALF OF LAKE SUPERIOR...WITH GUSTS OF 20-25KTS LATE TONIGHT INTO THURSDAY. THE RIDGE WILL SLOWLY SHIFT EAST FRIDAY...AS LOW PRESSURE ACROSS SOUTHERN MANITOBA AND NORTH DAKOTA APPROACHES NORTHERN MINNESOTA...BRINGING THE RETURN OF THUNDERSTORMS FRIDAY INTO SUNDAY. EXPECT THE LOW TO SHIFT ACROSS THE UPPER GREAT LAKES ON SATURDAY. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... DENSE FOG ADVISORY UNTIL NOON EDT WEDNESDAY FOR LSZ248>251- 265>267. LAKE MICHIGAN... NONE. && $$ SHORT TERM...VOSS LONG TERM...SRF AVIATION...JLB MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
359 PM EDT MON JUN 16 2014 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 358 PM EDT MON JUN 16 2014 LATEST WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A SHORTWAVE LIFTING NE THROUGH NEBRASKA/SOUTH DAKOTA WHICH TRIGGERED CONVECTION ACROSS ERN NE EARLIER THIS MORNING AND NOW HAS CONVECTION FOCUSED AT PRESENT OVER ERN SD AND SW MN AT NOSE OF ASSOC 40-45 KT LOW-LVL JET...BEST MLCAPE GRADIENT OF 2500-3000 J/KG AND 700-500 MB LAPSE RATES NEAR 8.5C/KM. HIGHER LAPSE RATES TO 7C/KM FARTHER NORTH ALSO SUPPORTING CLUSTER OF SHRA/ISOLD TSRA OVER NRN MN INTO FAR NRN WI. THIS ACTIVITY MAY SNEAK INTO FAR WRN UPPER MI LATE THIS AFTERNOON/EVENING BRINGING SOME LIGHT SHRA...BUT GENERALLY EXPECT THIS CONVECTION TO WEAKEN AND EVENTUALLY DIE OFF AS IT MOVES AWAY FROM THE BETTER INSTABILITY FARTHER TO THE SOUTH. FCST FOR TONIGHT INTO TUESDAY WILL LARGELY HINGE ON WHAT HAPPENS WITH CONVECTION WHICH HAS FORMED OVER SRN MN THIS AFTERNOON AND WHERE WARM FRONT WILL REMAIN SITUATED INTO TUESDAY. AS FAR AS CONVECTION TONIGHT...WILL LEAN MORE TOWARD A BLEND OF THE 12Z REGIONAL GEM AND GFS AND AWAY FROM THE 12Z NAM WHICH BRINGS STRONGEST CONVECTION TOO FAR NORTH INTO UPPER MI GIVEN MORE SOUTHWARD PLACEMENT OF WARM FRONT. FOLLOWING A BLEND OF THE 12Z REGIONAL GEM AND GFS...WILL CONTINUE ALONG WITH IDEA OF PREV FCST WITH MINOR TWEAKS KEEPING LIKELY TO CATEGORICAL POPS GENERALLY OVER THE SCNTRL AND ERN FCST AREA LATE TONIGHT INTO TUE MORNING WHERE THIS PORTION OF CWA WILL BE ON NRN FRINGE OF MCS ACTIVITY MOVING ACROSS THE MIDWEST. WITH HIGHEST MLCAPES TO NEAR 3000 J/KG AND 700-500 MB LAPSE RATES 8-9C/KM FCST TO STAY WELL SOUTH CLOSER TO WARM FRONT WOULD EXPECT ANY SVR STORMS TO STAY SOUTH OF UPPER MI TONIGHT...MAINLY ALONG AND JUST SOUTH OF WARM FRONT AS DEPICTED ON THE SPC DAY 1 OUTLOOK WHERE THE SLIGHT RISK LINE MAKES IT JUST SLIGHTLY NORTH OF GRB AND WAUSAW. BEST CHC OF TSRA TONIGHT WILL BE OVER SCNTRL UPPER MI CLOSER TO BETTER INSTABILITY AND STEEPER MID-LVL LAPSE RATES. MAY NEED TO WATCH FOR POTENTIAL WAKE LOW DEVELOPMENT LATE TONIGHT AS NRN FRINGE OF MCS MOVES ACROSS SCNTRL AND SE FCST AREA. THIS COULD LEAD TO GUSTY WINDS OVER THESE AREAS IN THE WAKE OF THE THUNDERSTORM COMPLEX. MODELS SHOW CONVECTION FROM DEVELOPING MCS EXITING THE ERN FCST AREA BY LATE TUE MORNING. MAIN QUESTION FOR TUE WILL BE CHCS FOR AFTERNOON CONVECTION ALONG THE WI BDR. WILL TREND TOWARD DRIER FCST FOR TUE PER REGIONAL GEM AND NAM WHICH KEEPS DEVELOPING AFTERNOON CONVECTION GENERALLY SOUTH OF CWA. SINCE THE 12Z GFS IS THE ONLY MODEL TO BRING THE WARM FRONT NORTH INTO UPPER MI WILL TEND TO SHY AWAY FROM ITS FARTHER NORTH CONVECTIVE DEVELOPMENT. WITH 8H TEMPS IN THE 14-16C...EXPECT INLAND HIGHS IN THE LOWER TO MID 80S INTERIOR WEST/SCNTRL TO UPPER 70S EAST...WITH COOLER 60S TEMPS ALONG THE GREAT LAKES SHORELINES FROM DEVELOPING LAKE BREEZES. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 326 PM EDT MON JUN 16 2014 AT THE START OF THE PERIOD...AN UPPER TROUGH WILL BE OVER THE ROCKIES AND NORTHERN QUEBEC...WHILE A WEAK UPPER RIDGE AXIS WILL STRETCH FROM THE LOWER MISSISSIPPI VALLEY TO LAKE WINNIPEG. AT THE SURFACE...A SURFACE LOW WILL BE LOCATED IN NORTHERN QUEBEC AND ALSO IN THE LEE OF THE ROCKIES...WITH A TROUGH STRETCHING BETWEEN THE TWO LOWS AND THROUGH THE CENTRAL GREAT LAKES REGION. TO THE NORTH OF THE TROUGH...A HIGH WILL BE CENTERED OVER WESTERN HUDSON BAY WITH A RIDGE STRETCHING SOUTH TO FAR NORTHERN LAKE SUPERIOR. THE HUDSON BAY HIGH AND SURFACE TROUGH WILL CONTROL MUCH OF THE FORECAST FOR THE MIDDLE/END OF THE WORK WEEK. THE LOCATION OF THE SURFACE TROUGH WILL LIKELY DEPEND ON THE EVOLUTION OF THE MCS MOVING OUT OF SOUTHERN MINNESOTA TONIGHT INTO TUESDAY MORNING. LATEST TRENDS SEEM TO BE FOR A LITTLE FARTHER SOUTH TRACK THAN SHOWN OVER THE LAST COUPLE OF DAYS AND THAT SEEMS REASONABLE. THAT MORE SOUTHERN IDEA WILL LIKELY POSITION THE TROUGH JUST TO THE SOUTH OF THE AREA FOR TUESDAY NIGHT AND ALLOW DRY NORTHEASTERLY FLOW AROUND THE HUDSON BAY HIGH TO MOVE OVER MUCH OF THE AREA. INDICATIONS ARE FOR ANOTHER SHORTWAVE TO LIFT NORTHEAST ALONG THE SURFACE TROUGH OR DEVELOPING WARM FRONT STRETCHING FROM SIOUX FALLS THROUGH SOUTHERN MN AND INTO CENTRAL/SOUTHERN WISCONSIN ON TUESDAY NIGHT AND KICK OF ANOTHER ROUND OF THUNDERSTORMS. WITH THIS BOUNDARY TO THE SOUTH OF THE AREA...FEEL THAT MUCH OF THE THUNDERSTORMS WILL STAY SOUTH OF THE AREA. THUS...WILL CONTINUE TO KEEP THE HIGHEST POPS (LOW END CHANCES) POSITIONED ALONG THE WISCONSIN BORDER AND SLIGHTS OVER THE SOUTHWEST HALF. WITH PROPAGATION VECTORS INDICATING MOVEMENT TO THE SOUTHEAST...WOULD THINK THAT AT MOST WE WOULD ONLY SEE THE NORTHERN EDGE OF THE CONVECTIVELY INDUCED STRATIFORM PRECIP. WITH THE EXPECTATION OF THE BOUNDARY STAYING TO THE SOUTH...THE SURFACE RIDGE FROM THE HUDSON BAY WILL PUSH OVER AT LEAST THE NORTHEAST HALF OF THE CWA AND LEAD TO DRY AND LIGHT NORTHEASTERLY FLOW FOR WEDNESDAY INTO THURSDAY. WILL FOLLOW THE SAME IDEA AS FOR TUESDAY NIGHT AND KEEP THE BEST POPS (LOW CHANCES) RIGHT ALONG THE WISCONSIN BORDER...ALTHOUGH THAT MAY BE OVERDONE (ESPECIALLY SINCE THE WEAK UPPER RIDGE WILL BE SLIDING ACROSS THE UPPER GREAT LAKES). OTHERWISE...SHOULD SEE PARTLY CLOUDY SKIES OR JUST HIGH CLOUDS STREAMING OVER THE AREA DURING THIS TIME. NORTHEASTERLY FLOW OFF LAKE SUPERIOR WILL KEEP HIGHS COOLEST NEAR THE SHORELINE...WITH INLAND VALUES IN THE 70S. UNFORTUNATELY FOR THE EAST...THIS DRIER PERIOD WILL CONTINUE THE DRY CONDITIONS EXPERIENCED OVER THE LAST 30 DAYS (GENERALLY UNDER 50 PERCENT OF NORMAL). THE UPPER TROUGH THAT IS OVER THE ROCKIES TO START THE PERIOD WILL BEGIN TO LIFT INTO THE NORTHERN PLAINS ON THURSDAY AND THEN SLOWLY SHIFT EAST WHILE MERGING WITH THE NEARLY STATIONARY UPPER LOW OVER EASTERN QUEBEC THIS WEEKEND. THIS WILL GRADUALLY INCREASE PRECIPITATION CHANCES THURSDAY NIGHT INTO FRIDAY FROM WEST TO EAST...AS THE SURFACE LOW MOVES INTO NORTHWEST MINNESOTA. THE CHANCE POPS WILL CONTINUE INTO THIS WEEKEND AS THE WEAKENING SURFACE LOW CONTINUES ITS EASTWARD TRACK. MODEL MUCAPE AND SHOWALTER VALUES SLOWLY DIMINISH AS IT MOVES INTO THE AREA...SO WOULD EXPECT THUNDER CHANCES TO BE LIMITED AND WILL MATCH WITH THE POPS FOR NOW. MODELS DIFFER ON HOW QUICKLY THIS UPPER TROUGH AND SURFACE LOW WILL DEPART THE UPPER GREAT LAKES REGION ON SUNDAY/MONDAY...SO WILL FOLLOW A GENERAL CONSENSUS OF CHANCE/SLIGHT POPS SUNDAY DIMINISHING BY MONDAY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 139 PM EDT MON JUN 16 2014 UNDER A DRY AIR MASS...VFR CONDITIONS WILL PREVAIL INTO THIS EVENING AT KIWD/KCMX/KSAW. LATE TONIGHT...A DISTURBANCE WILL GENERATE A COMPLEX OF SHRA/TSTMS THAT WILL MOVE INTO THE WESTERN GREAT LAKES...AND UPPER MI WILL BE ON THE NRN END OF THE COMPLEX. CONDITIONS WILL LIKELY FALL TO MVFR LATE TONIGHT WITH IFR POSSIBLE AT KIWD AS WINDS MAY SWING AROUND TO AN UPSLOPE NW DIRECTION AROUND SUNRISE. WITH THE POTENTIAL FOR STEADIER PCPN TO AFFECT KSAW INCLUDED MVFR CONDITIONS DEVELOPING THERE BTWN 10-15Z. EXPECT BETTER CHCS TO TSRA TO STAY SOUTH OF SAW SO REMOVED VCTS. WITH DIURNAL MIXING LOOK IMPROVEMENT AT ALL SITES BY LATE TUE MORNING. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 358 PM EDT MON JUN 16 2014 WEAK PRES GRADIENT SHOULD KEEP WINDS MOSTLY UNDER 20KT THRU TUE. HOWEVER...DEPENDING ON THE TRACK OF A CLUSTER OF SHRA/TSTMS PASSING THRU WI AND AT LEAST PARTS OF UPPER MI LATE TONIGHT/TUE MORNING...THERE MAY BE LOCALLY HIGHER WINDS FOR A TIME LATE TONIGHT/TUE MORNING. FROM LATE TUE THRU FRI...LAKE SUPERIOR WILL BECOME SITUATED BTWN A HUDSON BAY HIGH AND A LOW PRES TROF SLOWLY ADVANCING ACROSS THE PLAINS. THIS WILL RESULT IN EASTERLY WINDS LATER TUE THRU FRI. WHILE WINDS SHOULD GENERALLY BE UNDER 20KT...THIS TYPE OF PATTERN IS FAVORABLE FOR STRONGER WINDS OVER THE WRN PART OF THE LAKE...ESPECIALLY TOWARD THE MN N SHORE DUE TO COASTAL CONVERGENCE/FUNNELING. OTHERWISE...WINDS OVERALL COULD BE STRONGER DEPENDING ON THE STRENGTH OF THE HIGH PRES AND LOW PRES. WITH THE POTENTIAL FOR RAIN TONIGHT AND LINGERING HIGHER DEWPOINTS OVER THE AREA INTO WED...LOOK FOR SOME PATCHY FOG TO REDEVELOP ACROSS MUCH OF THE LAKE. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...VOSS LONG TERM...SRF AVIATION...VOSS MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
327 PM EDT MON JUN 16 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 537 AM EDT MON JUN 16 2014 WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW THAT THE NEGATIVE TILT SHORTWAVE THAT LIFTED THRU THE UPPER MISSISSIPPI VALLEY YESTERDAY HAS BECOME AN IMPRESSIVE LOOKING MID LEVEL LOW OVER NRN ONTARIO EARLY THIS MORNING. SUBTLE SHORTWAVE ROTATING AROUND THE LOW MANAGED TO SPARK A FEW -SHRA OVER WRN LAKE SUPERIOR/FAR WRN UPPER MI FROM AROUND KIWD TO THE KEWEENAW PENINSULA OVERNIGHT/EARLY THIS MORNING. OTHERWISE...AS EXPECTED SKIES HAVE LARGELY CLEARED ACROSS THE FCST AREA AS MUCH DRIER AIR...ESPECIALLY IN THE MID LEVELS...HAS ADVECTED INTO THE AREA. AT THE VERY LOW-LEVELS...YESTERDAY`S RAINFALL AND DIMINISHING WINDS UNDERNEATH THE MID LEVEL DRYING HAVE RESULTED IN FOG FORMATION OVER A GOOD PORTION OF CNTRL UPPER MI. WITH DECENT WINDS JUST ABOVE THE SFC (KMQT RADAR SHOWS 25KT SW WINDS AT 500FT AGL)...FOG SHOULD QUICKLY DISPERSE WITHIN A COUPLE OF HRS AFTER SUNRISE. HOWEVER...NEAR LAKE MICHIGAN...PATCHY FOG MAY PLAGUE LAKESIDE LOCATIONS INTO THE AFTN HRS. OTHERWISE...LOOKS LIKE A MAINLY SUNNY AND MUCH WARMER DAY IS SHAPING UP. FCST SOUNDINGS INDICATE A DEEP MIXING DAY WITH BOUNDARY LAYER BUILDING TO TOWARD 750MB. THIS YIELDS MAX TEMPS INTO 80-85 RANGE OVER MUCH OF THE AREA...BUT IT WILL BE COOLER NEAR LAKE MICHIGAN WITH PREVAILING S/SW WINDS. A NUMBER OF HIGH RES MODELS INDICATE LAKE BREEZE DEVELOPMENT NEAR LAKE SUPERIOR...AND THIS IS INCREASINGLY INDICATED BY HOURLY RUC13 MODEL RUNS. DEVELOPMENT SHOULD OCCUR LATE ENOUGH IN THE DAY TO STILL ALLOW MOST LOCATIONS NEAR LAKE SUPERIOR TO GET IN ON THE WARMTH TODAY AS WELL. DEEP MIXING WILL AID IN LOWERING DWPTS THIS AFTN. INCORPORATED MIXED LAYER DWPTS INTO THE FCST WHICH RESULTS IN DWPTS FALLING INTO THE MID/UPPER 40S IN THE INTERIOR...AND THIS PUTS MIN RH DOWN AROUND 30PCT. THE DEEP MIXING SHOULD ALSO LEAD TO GUSTY WINDS INTO THE 20-30MPH RANGE FOR A TIME WHERE RH IS LOWEST. FORTUNATELY...YESTERDAYS RAINFALL AND NEAR SATURATED SFC LAYER/DEW FORMATION OVERNIGHT WILL MITIGATE SOME OF THE FIRE WX CONCERNS. ONE LAST ISSUE FOR TODAY IS THE POTENTIAL FOR ISOLD CONVECTION. GFS SHOWS MLCAPE UPWARDS OF AROUND 500J/KG OVER ROUGHLY THE W HALF TODAY WHILE THE NAM IS BIT HIGHER TO 500-900J/KG. THERE IS SUFFICIENT MOISTURE FOR POSSIBLE CONVECTION (A SIMPLE LOOK AT K INDEX SHOWS VALUES UP TO AROUND 30 ON THE GFS AND A LITTLE HIGHER WITH THE NAM). HOWEVER...GIVEN 40-60M HEIGHT RISES AT 500MB TODAY WITH SHORTWAVE RIDGING APPROACHING...WILL HOLD OFF ON INTRODUCING ANY PCPN MENTION. AS OPPOSED TO PREVIOUS DAYS MODEL RUNS...MOST MODELS NOW SHOW A DRY DAY ACROSS THE FCST AREA...FURTHER SUPPORTING THE DRY FCST. THAT SAID...WILL NEED TO KEEP AN EYE ON LAKE SUPERIOR LAKE BREEZE DEVELOPMENT AS THAT COULD TRIGGER ISOLD LATE AFTN CONVECTION. TONIGHT...ATTENTION TURNS TO SHORTWAVE LIFTING NE FROM THE PLAINS. SIGNIFICANT BUILD UP OF INSTABILITY TODAY COMBINED WITH LOW-LEVEL JET DEVELOPING IN RESPONSE TO SHORTWAVE WILL TRIGGER THE DEVELOPMENT OF STRONG CONVECTION SOMEWHERE OVER NE/SD/IA/SRN MN LATER THIS AFTN. THIS CONVECTION WILL LIKELY GROW INTO AN MCS TONIGHT THAT WILL RIDE ENE IN CONJUNCTION WITH ENE TRACKING SHORTWAVE. WHILE SVR THREAT SHOULD PASS S OF THE FCST AREA CLOSER TO MAX INSTABILITY AND INSTABILITY GRADIENT...NOT OUT OF THE QUESTION FOR STRONGER STORMS TO SLIP INTO SRN UPPER MI LATE TONIGHT. FOR NOW...PREFER THE LOOK OF THE 00Z REGIONAL GEM WITH RESPECT TO EXPECTED MCS DEVELOPMENT/MOVEMENT. THIS MODEL BRINGS SHRA/TSRA INTO MAINLY CNTRL/ERN UPPER MI LATE TONIGHT. THE HIGH RES NAM WINDOW IS SIMILAR TO THE GEM THOUGH A BIT FARTHER N THAN THE GEM. BEING ON THE NRN END OF THE MCS...HVY RAINFALL MAY AFFECT PORTIONS OF THE FCST AREA...BUT THAT WILL DEPEND ON THE EVOLUTION/STRUCTURE OF THE MCS. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 326 PM EDT MON JUN 16 2014 AT THE START OF THE PERIOD...AN UPPER TROUGH WILL BE OVER THE ROCKIES AND NORTHERN QUEBEC...WHILE A WEAK UPPER RIDGE AXIS WILL STRETCH FROM THE LOWER MISSISSIPPI VALLEY TO LAKE WINNIPEG. AT THE SURFACE...A SURFACE LOW WILL BE LOCATED IN NORTHERN QUEBEC AND ALSO IN THE LEE OF THE ROCKIES...WITH A TROUGH STRETCHING BETWEEN THE TWO LOWS AND THROUGH THE CENTRAL GREAT LAKES REGION. TO THE NORTH OF THE TROUGH...A HIGH WILL BE CENTERED OVER WESTERN HUDSON BAY WITH A RIDGE STRETCHING SOUTH TO FAR NORTHERN LAKE SUPERIOR. THE HUDSON BAY HIGH AND SURFACE TROUGH WILL CONTROL MUCH OF THE FORECAST FOR THE MIDDLE/END OF THE WORK WEEK. THE LOCATION OF THE SURFACE TROUGH WILL LIKELY DEPEND ON THE EVOLUTION OF THE MCS MOVING OUT OF SOUTHERN MINNESOTA TONIGHT INTO TUESDAY MORNING. LATEST TRENDS SEEM TO BE FOR A LITTLE FARTHER SOUTH TRACK THAN SHOWN OVER THE LAST COUPLE OF DAYS AND THAT SEEMS REASONABLE. THAT MORE SOUTHERN IDEA WILL LIKELY POSITION THE TROUGH JUST TO THE SOUTH OF THE AREA FOR TUESDAY NIGHT AND ALLOW DRY NORTHEASTERLY FLOW AROUND THE HUDSON BAY HIGH TO MOVE OVER MUCH OF THE AREA. INDICATIONS ARE FOR ANOTHER SHORTWAVE TO LIFT NORTHEAST ALONG THE SURFACE TROUGH OR DEVELOPING WARM FRONT STRETCHING FROM SIOUX FALLS THROUGH SOUTHERN MN AND INTO CENTRAL/SOUTHERN WISCONSIN ON TUESDAY NIGHT AND KICK OF ANOTHER ROUND OF THUNDERSTORMS. WITH THIS BOUNDARY TO THE SOUTH OF THE AREA...FEEL THAT MUCH OF THE THUNDERSTORMS WILL STAY SOUTH OF THE AREA. THUS...WILL CONTINUE TO KEEP THE HIGHEST POPS (LOW END CHANCES) POSITIONED ALONG THE WISCONSIN BORDER AND SLIGHTS OVER THE SOUTHWEST HALF. WITH PROPAGATION VECTORS INDICATING MOVEMENT TO THE SOUTHEAST...WOULD THINK THAT AT MOST WE WOULD ONLY SEE THE NORTHERN EDGE OF THE CONVECTIVELY INDUCED STRATIFORM PRECIP. WITH THE EXPECTATION OF THE BOUNDARY STAYING TO THE SOUTH...THE SURFACE RIDGE FROM THE HUDSON BAY WILL PUSH OVER AT LEAST THE NORTHEAST HALF OF THE CWA AND LEAD TO DRY AND LIGHT NORTHEASTERLY FLOW FOR WEDNESDAY INTO THURSDAY. WILL FOLLOW THE SAME IDEA AS FOR TUESDAY NIGHT AND KEEP THE BEST POPS (LOW CHANCES) RIGHT ALONG THE WISCONSIN BORDER...ALTHOUGH THAT MAY BE OVERDONE (ESPECIALLY SINCE THE WEAK UPPER RIDGE WILL BE SLIDING ACROSS THE UPPER GREAT LAKES). OTHERWISE...SHOULD SEE PARTLY CLOUDY SKIES OR JUST HIGH CLOUDS STREAMING OVER THE AREA DURING THIS TIME. NORTHEASTERLY FLOW OFF LAKE SUPERIOR WILL KEEP HIGHS COOLEST NEAR THE SHORELINE...WITH INLAND VALUES IN THE 70S. UNFORTUNATELY FOR THE EAST...THIS DRIER PERIOD WILL CONTINUE THE DRY CONDITIONS EXPERIENCED OVER THE LAST 30 DAYS (GENERALLY UNDER 50 PERCENT OF NORMAL). THE UPPER TROUGH THAT IS OVER THE ROCKIES TO START THE PERIOD WILL BEGIN TO LIFT INTO THE NORTHERN PLAINS ON THURSDAY AND THEN SLOWLY SHIFT EAST WHILE MERGING WITH THE NEARLY STATIONARY UPPER LOW OVER EASTERN QUEBEC THIS WEEKEND. THIS WILL GRADUALLY INCREASE PRECIPITATION CHANCES THURSDAY NIGHT INTO FRIDAY FROM WEST TO EAST...AS THE SURFACE LOW MOVES INTO NORTHWEST MINNESOTA. THE CHANCE POPS WILL CONTINUE INTO THIS WEEKEND AS THE WEAKENING SURFACE LOW CONTINUES ITS EASTWARD TRACK. MODEL MUCAPE AND SHOWALTER VALUES SLOWLY DIMINISH AS IT MOVES INTO THE AREA...SO WOULD EXPECT THUNDER CHANCES TO BE LIMITED AND WILL MATCH WITH THE POPS FOR NOW. MODELS DIFFER ON HOW QUICKLY THIS UPPER TROUGH AND SURFACE LOW WILL DEPART THE UPPER GREAT LAKES REGION ON SUNDAY/MONDAY...SO WILL FOLLOW A GENERAL CONSENSUS OF CHANCE/SLIGHT POPS SUNDAY DIMINISHING BY MONDAY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 139 PM EDT MON JUN 16 2014 UNDER A DRY AIR MASS...VFR CONDITIONS WILL PREVAIL INTO THIS EVENING AT KIWD/KCMX/KSAW. LATE TONIGHT...A DISTURBANCE WILL GENERATE A COMPLEX OF SHRA/TSTMS THAT WILL MOVE INTO THE WESTERN GREAT LAKES...AND UPPER MI WILL BE ON THE NRN END OF THE COMPLEX. CONDITIONS WILL LIKELY FALL TO MVFR LATE TONIGHT WITH IFR POSSIBLE AT KIWD AS WINDS MAY SWING AROUND TO AN UPSLOPE NW DIRECTION AROUND SUNRISE. WITH THE POTENTIAL FOR STEADIER PCPN TO AFFECT KSAW INCLUDED MVFR CONDITIONS DEVELOPING THERE BTWN 10-15Z. EXPECT BETTER CHCS TO TSRA TO STAY SOUTH OF SAW SO REMOVED VCTS. WITH DIURNAL MIXING LOOK IMPROVEMENT AT ALL SITES BY LATE TUE MORNING. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 537 AM EDT MON JUN 16 2014 WINDS WILL CONTINUE TO DIMINISH ACROSS LAKE SUPERIOR TODAY AS PRES GRADIENT WEAKENS. THESE LIGHTER WINDS...MOSTLY UNDER 20KT...WILL CONTINUE THRU TUE. HOWEVER...DEPENDING ON THE TRACK OF A CLUSTER OF SHRA/TSTMS PASSING THRU WI AND AT LEAST PARTS OF UPPER MI LATE TONIGHT/TUE MORNING...THERE MAY BE LOCALLY HIGHER WINDS FOR A TIME LATE TONIGHT/TUE MORNING. FROM LATE TUE THRU FRI...LAKE SUPERIOR WILL BECOME SITUATED BTWN A HUDSON BAY HIGH AND A LOW PRES TROF SLOWLY ADVANCING ACROSS THE PLAINS. THIS WILL RESULT IN EASTERLY WINDS LATER TUE THRU FRI. WHILE WINDS SHOULD GENERALLY BE UNDER 20KT...THIS TYPE OF PATTERN IS FAVORABLE FOR STRONGER WINDS OVER THE WRN PART OF THE LAKE...ESPECIALLY TOWARD THE MN N SHORE DUE TO COASTAL CONVERGENCE/FUNNELING. OTHERWISE...WINDS OVERALL COULD BE STRONGER DEPENDING ON THE STRENGTH OF THE HIGH PRES AND LOW PRES. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...SRF AVIATION...VOSS MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
149 PM EDT MON JUN 16 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 537 AM EDT MON JUN 16 2014 WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW THAT THE NEGATIVE TILT SHORTWAVE THAT LIFTED THRU THE UPPER MISSISSIPPI VALLEY YESTERDAY HAS BECOME AN IMPRESSIVE LOOKING MID LEVEL LOW OVER NRN ONTARIO EARLY THIS MORNING. SUBTLE SHORTWAVE ROTATING AROUND THE LOW MANAGED TO SPARK A FEW -SHRA OVER WRN LAKE SUPERIOR/FAR WRN UPPER MI FROM AROUND KIWD TO THE KEWEENAW PENINSULA OVERNIGHT/EARLY THIS MORNING. OTHERWISE...AS EXPECTED SKIES HAVE LARGELY CLEARED ACROSS THE FCST AREA AS MUCH DRIER AIR...ESPECIALLY IN THE MID LEVELS...HAS ADVECTED INTO THE AREA. AT THE VERY LOW-LEVELS...YESTERDAY`S RAINFALL AND DIMINISHING WINDS UNDERNEATH THE MID LEVEL DRYING HAVE RESULTED IN FOG FORMATION OVER A GOOD PORTION OF CNTRL UPPER MI. WITH DECENT WINDS JUST ABOVE THE SFC (KMQT RADAR SHOWS 25KT SW WINDS AT 500FT AGL)...FOG SHOULD QUICKLY DISPERSE WITHIN A COUPLE OF HRS AFTER SUNRISE. HOWEVER...NEAR LAKE MICHIGAN...PATCHY FOG MAY PLAGUE LAKESIDE LOCATIONS INTO THE AFTN HRS. OTHERWISE...LOOKS LIKE A MAINLY SUNNY AND MUCH WARMER DAY IS SHAPING UP. FCST SOUNDINGS INDICATE A DEEP MIXING DAY WITH BOUNDARY LAYER BUILDING TO TOWARD 750MB. THIS YIELDS MAX TEMPS INTO 80-85 RANGE OVER MUCH OF THE AREA...BUT IT WILL BE COOLER NEAR LAKE MICHIGAN WITH PREVAILING S/SW WINDS. A NUMBER OF HIGH RES MODELS INDICATE LAKE BREEZE DEVELOPMENT NEAR LAKE SUPERIOR...AND THIS IS INCREASINGLY INDICATED BY HOURLY RUC13 MODEL RUNS. DEVELOPMENT SHOULD OCCUR LATE ENOUGH IN THE DAY TO STILL ALLOW MOST LOCATIONS NEAR LAKE SUPERIOR TO GET IN ON THE WARMTH TODAY AS WELL. DEEP MIXING WILL AID IN LOWERING DWPTS THIS AFTN. INCORPORATED MIXED LAYER DWPTS INTO THE FCST WHICH RESULTS IN DWPTS FALLING INTO THE MID/UPPER 40S IN THE INTERIOR...AND THIS PUTS MIN RH DOWN AROUND 30PCT. THE DEEP MIXING SHOULD ALSO LEAD TO GUSTY WINDS INTO THE 20-30MPH RANGE FOR A TIME WHERE RH IS LOWEST. FORTUNATELY...YESTERDAYS RAINFALL AND NEAR SATURATED SFC LAYER/DEW FORMATION OVERNIGHT WILL MITIGATE SOME OF THE FIRE WX CONCERNS. ONE LAST ISSUE FOR TODAY IS THE POTENTIAL FOR ISOLD CONVECTION. GFS SHOWS MLCAPE UPWARDS OF AROUND 500J/KG OVER ROUGHLY THE W HALF TODAY WHILE THE NAM IS BIT HIGHER TO 500-900J/KG. THERE IS SUFFICIENT MOISTURE FOR POSSIBLE CONVECTION (A SIMPLE LOOK AT K INDEX SHOWS VALUES UP TO AROUND 30 ON THE GFS AND A LITTLE HIGHER WITH THE NAM). HOWEVER...GIVEN 40-60M HEIGHT RISES AT 500MB TODAY WITH SHORTWAVE RIDGING APPROACHING...WILL HOLD OFF ON INTRODUCING ANY PCPN MENTION. AS OPPOSED TO PREVIOUS DAYS MODEL RUNS...MOST MODELS NOW SHOW A DRY DAY ACROSS THE FCST AREA...FURTHER SUPPORTING THE DRY FCST. THAT SAID...WILL NEED TO KEEP AN EYE ON LAKE SUPERIOR LAKE BREEZE DEVELOPMENT AS THAT COULD TRIGGER ISOLD LATE AFTN CONVECTION. TONIGHT...ATTENTION TURNS TO SHORTWAVE LIFTING NE FROM THE PLAINS. SIGNIFICANT BUILD UP OF INSTABILITY TODAY COMBINED WITH LOW-LEVEL JET DEVELOPING IN RESPONSE TO SHORTWAVE WILL TRIGGER THE DEVELOPMENT OF STRONG CONVECTION SOMEWHERE OVER NE/SD/IA/SRN MN LATER THIS AFTN. THIS CONVECTION WILL LIKELY GROW INTO AN MCS TONIGHT THAT WILL RIDE ENE IN CONJUNCTION WITH ENE TRACKING SHORTWAVE. WHILE SVR THREAT SHOULD PASS S OF THE FCST AREA CLOSER TO MAX INSTABILITY AND INSTABILITY GRADIENT...NOT OUT OF THE QUESTION FOR STRONGER STORMS TO SLIP INTO SRN UPPER MI LATE TONIGHT. FOR NOW...PREFER THE LOOK OF THE 00Z REGIONAL GEM WITH RESPECT TO EXPECTED MCS DEVELOPMENT/MOVEMENT. THIS MODEL BRINGS SHRA/TSRA INTO MAINLY CNTRL/ERN UPPER MI LATE TONIGHT. THE HIGH RES NAM WINDOW IS SIMILAR TO THE GEM THOUGH A BIT FARTHER N THAN THE GEM. BEING ON THE NRN END OF THE MCS...HVY RAINFALL MAY AFFECT PORTIONS OF THE FCST AREA...BUT THAT WILL DEPEND ON THE EVOLUTION/STRUCTURE OF THE MCS. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 503 AM EDT MON JUN 16 2014 SMALL DISTURBANCES WILL PLAGUE MUCH OF THIS PERIOD...WHICH WILL REMAIN DIFFICULT TO TIME. THE BEST CHANCE OF CONVECTION WILL BE NEAR THE WI BORDER. WINDS TUESDAY SHOULD BE LESS THAN 10KTS...BUT THE DIRECTION IS STILL IN QUESTION. THIS IN BECAUSE OF THE VARIED PLACEMENT OF A WEAK SFC LOW ACROSS THE UPPER GREAT LAKES. THE 16/00Z NAM PLACES THIS FEATURE OVER THE KEWEENAW PENINSULA AT 12Z TUESDAY...WHILE THE CANADIAN IS ACROSS THE CENTRAL U.P....AND THE 15/12Z ECMWF IS APPROX 160MI S OF THE NAM. WILL GO WITH A GENERAL BLEND...AND LIKE AS STATED ABOVE WINDS SHOULD BE LESS THAN 10KTS...SO DO NOT EXPECT TOO MANY PROBLEMS WITH THIS SOLUTION BEFORE THE RIDGE PUSHES IN FROM THE NW IN THE AFTERNOON. RH VALUES SHOULD BOTTOM OUT BETWEEN 45 AND 55 PERCENT. OVERALL...LOOK FOR A DIMINISHING TREND TO THE SHOWERS AND THUNDERSTORMS TUESDAY. THE 500MB RIDGE WILL REMAIN JUST W OF THE UPPER GREAT LAKES UNTIL THURSDAY MORNING...AS THE SFC RIDGE STRENGTHENS IT/S HOLD OVER UPPER MI. EXPECT E-NE WINDS TUESDAY NIGHT THROUGH WEDNESDAY NIGHT. LINGERING FOG ACROSS LAKE SUPERIOR SHOULD SLOWLY ERODE FROM N TO S DURING THE DAY WEDNESDAY. UNSETTLED WX WILL LIKELY REMAIN OFF AND ON MAINLY NEAR THE WI BORDER...CLOSER TO THE BETTER MOISTURE. WINDS WILL INCREASE WEDNESDAY NIGHT INTO THURSDAY...IN RESPONSE TO THE INCREASED PRESSURE GRADIENT BETWEEN THE SFC RIDGE OVER THE E HALF OF ONTARIO AND THE NEARING LOW ACROSS NE AND SD. STILL...THE E FLOW SHOULD STILL KEEP TEMPS FROM WARMING MUCH MORE THAN THE MID 70S ACROSS MUCH OF THE CWA...AS 850MB TEMPS LINGER BETWEEN 10-13C. THE SFC LOW OVER S CENTRAL CANADA AND THE N PLAINS THURSDAY AFTERNOON WILL REMAIN NEARLY STATIONARY...BUT WITH A SLIGHT E PUSH AS THE 500MB WAVE OVER THE DAKOTAS AT 00Z FRIDAY KICKS SLIGHTLY NNE TOWARD MN. THE NEXT BEST CHANCE OF WIDESPREAD PRECIP /AT LEAST W AND CENTRAL/ WILL LIKELY BE DURING THE DAY FRIDAY. THERE ARE SOME INDICATIONS THAT E AREAS COULD BE SEVERAL DEGREES WARMER THAN CURRENTLY FCST FRIDAY...IF RAIN/CLOUDS HOLD OFF UNTIL THE MID TO LATE AFTERNOON HOURS. THE SPREAD BETWEEN THE FCST SOLUTIONS IS SIGNIFICANT FOR THIS TIME PERIOD...SO WILL NOT MAKE ANY LARGE CHANGES TO THE ONGOING FCST. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 139 PM EDT MON JUN 16 2014 UNDER A DRY AIR MASS...VFR CONDITIONS WILL PREVAIL INTO THIS EVENING AT KIWD/KCMX/KSAW. LATE TONIGHT...A DISTURBANCE WILL GENERATE A COMPLEX OF SHRA/TSTMS THAT WILL MOVE INTO THE WESTERN GREAT LAKES...AND UPPER MI WILL BE ON THE NRN END OF THE COMPLEX. CONDITIONS WILL LIKELY FALL TO MVFR LATE TONIGHT WITH IFR POSSIBLE AT KIWD AS WINDS MAY SWING AROUND TO AN UPSLOPE NW DIRECTION AROUND SUNRISE. WITH THE POTENTIAL FOR STEADIER PCPN TO AFFECT KSAW INCLUDED MVFR CONDITIONS DEVELOPING THERE BTWN 10-15Z. EXPECT BETTER CHCS TO TSRA TO STAY SOUTH OF SAW SO REMOVED VCTS. WITH DIURNAL MIXING LOOK IMPROVEMENT AT ALL SITES BY LATE TUE MORNING. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 537 AM EDT MON JUN 16 2014 WINDS WILL CONTINUE TO DIMINISH ACROSS LAKE SUPERIOR TODAY AS PRES GRADIENT WEAKENS. THESE LIGHTER WINDS...MOSTLY UNDER 20KT...WILL CONTINUE THRU TUE. HOWEVER...DEPENDING ON THE TRACK OF A CLUSTER OF SHRA/TSTMS PASSING THRU WI AND AT LEAST PARTS OF UPPER MI LATE TONIGHT/TUE MORNING...THERE MAY BE LOCALLY HIGHER WINDS FOR A TIME LATE TONIGHT/TUE MORNING. FROM LATE TUE THRU FRI...LAKE SUPERIOR WILL BECOME SITUATED BTWN A HUDSON BAY HIGH AND A LOW PRES TROF SLOWLY ADVANCING ACROSS THE PLAINS. THIS WILL RESULT IN EASTERLY WINDS LATER TUE THRU FRI. WHILE WINDS SHOULD GENERALLY BE UNDER 20KT...THIS TYPE OF PATTERN IS FAVORABLE FOR STRONGER WINDS OVER THE WRN PART OF THE LAKE...ESPECIALLY TOWARD THE MN N SHORE DUE TO COASTAL CONVERGENCE/FUNNELING. OTHERWISE...WINDS OVERALL COULD BE STRONGER DEPENDING ON THE STRENGTH OF THE HIGH PRES AND LOW PRES. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...KF AVIATION...VOSS MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
742 AM EDT MON JUN 16 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 537 AM EDT MON JUN 16 2014 WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW THAT THE NEGATIVE TILT SHORTWAVE THAT LIFTED THRU THE UPPER MISSISSIPPI VALLEY YESTERDAY HAS BECOME AN IMPRESSIVE LOOKING MID LEVEL LOW OVER NRN ONTARIO EARLY THIS MORNING. SUBTLE SHORTWAVE ROTATING AROUND THE LOW MANAGED TO SPARK A FEW -SHRA OVER WRN LAKE SUPERIOR/FAR WRN UPPER MI FROM AROUND KIWD TO THE KEWEENAW PENINSULA OVERNIGHT/EARLY THIS MORNING. OTHERWISE...AS EXPECTED SKIES HAVE LARGELY CLEARED ACROSS THE FCST AREA AS MUCH DRIER AIR...ESPECIALLY IN THE MID LEVELS...HAS ADVECTED INTO THE AREA. AT THE VERY LOW-LEVELS...YESTERDAY`S RAINFALL AND DIMINISHING WINDS UNDERNEATH THE MID LEVEL DRYING HAVE RESULTED IN FOG FORMATION OVER A GOOD PORTION OF CNTRL UPPER MI. WITH DECENT WINDS JUST ABOVE THE SFC (KMQT RADAR SHOWS 25KT SW WINDS AT 500FT AGL)...FOG SHOULD QUICKLY DISPERSE WITHIN A COUPLE OF HRS AFTER SUNRISE. HOWEVER...NEAR LAKE MICHIGAN...PATCHY FOG MAY PLAGUE LAKESIDE LOCATIONS INTO THE AFTN HRS. OTHERWISE...LOOKS LIKE A MAINLY SUNNY AND MUCH WARMER DAY IS SHAPING UP. FCST SOUNDINGS INDICATE A DEEP MIXING DAY WITH BOUNDARY LAYER BUILDING TO TOWARD 750MB. THIS YIELDS MAX TEMPS INTO 80-85 RANGE OVER MUCH OF THE AREA...BUT IT WILL BE COOLER NEAR LAKE MICHIGAN WITH PREVAILING S/SW WINDS. A NUMBER OF HIGH RES MODELS INDICATE LAKE BREEZE DEVELOPMENT NEAR LAKE SUPERIOR...AND THIS IS INCREASINGLY INDICATED BY HOURLY RUC13 MODEL RUNS. DEVELOPMENT SHOULD OCCUR LATE ENOUGH IN THE DAY TO STILL ALLOW MOST LOCATIONS NEAR LAKE SUPERIOR TO GET IN ON THE WARMTH TODAY AS WELL. DEEP MIXING WILL AID IN LOWERING DWPTS THIS AFTN. INCORPORATED MIXED LAYER DWPTS INTO THE FCST WHICH RESULTS IN DWPTS FALLING INTO THE MID/UPPER 40S IN THE INTERIOR...AND THIS PUTS MIN RH DOWN AROUND 30PCT. THE DEEP MIXING SHOULD ALSO LEAD TO GUSTY WINDS INTO THE 20-30MPH RANGE FOR A TIME WHERE RH IS LOWEST. FORTUNATELY...YESTERDAYS RAINFALL AND NEAR SATURATED SFC LAYER/DEW FORMATION OVERNIGHT WILL MITIGATE SOME OF THE FIRE WX CONCERNS. ONE LAST ISSUE FOR TODAY IS THE POTENTIAL FOR ISOLD CONVECTION. GFS SHOWS MLCAPE UPWARDS OF AROUND 500J/KG OVER ROUGHLY THE W HALF TODAY WHILE THE NAM IS BIT HIGHER TO 500-900J/KG. THERE IS SUFFICIENT MOISTURE FOR POSSIBLE CONVECTION (A SIMPLE LOOK AT K INDEX SHOWS VALUES UP TO AROUND 30 ON THE GFS AND A LITTLE HIGHER WITH THE NAM). HOWEVER...GIVEN 40-60M HEIGHT RISES AT 500MB TODAY WITH SHORTWAVE RIDGING APPROACHING...WILL HOLD OFF ON INTRODUCING ANY PCPN MENTION. AS OPPOSED TO PREVIOUS DAYS MODEL RUNS...MOST MODELS NOW SHOW A DRY DAY ACROSS THE FCST AREA...FURTHER SUPPORTING THE DRY FCST. THAT SAID...WILL NEED TO KEEP AN EYE ON LAKE SUPERIOR LAKE BREEZE DEVELOPMENT AS THAT COULD TRIGGER ISOLD LATE AFTN CONVECTION. TONIGHT...ATTENTION TURNS TO SHORTWAVE LIFTING NE FROM THE PLAINS. SIGNIFICANT BUILD UP OF INSTABILITY TODAY COMBINED WITH LOW-LEVEL JET DEVELOPING IN RESPONSE TO SHORTWAVE WILL TRIGGER THE DEVELOPMENT OF STRONG CONVECTION SOMEWHERE OVER NE/SD/IA/SRN MN LATER THIS AFTN. THIS CONVECTION WILL LIKELY GROW INTO AN MCS TONIGHT THAT WILL RIDE ENE IN CONJUNCTION WITH ENE TRACKING SHORTWAVE. WHILE SVR THREAT SHOULD PASS S OF THE FCST AREA CLOSER TO MAX INSTABILITY AND INSTABILITY GRADIENT...NOT OUT OF THE QUESTION FOR STRONGER STORMS TO SLIP INTO SRN UPPER MI LATE TONIGHT. FOR NOW...PREFER THE LOOK OF THE 00Z REGIONAL GEM WITH RESPECT TO EXPECTED MCS DEVELOPMENT/MOVEMENT. THIS MODEL BRINGS SHRA/TSRA INTO MAINLY CNTRL/ERN UPPER MI LATE TONIGHT. THE HIGH RES NAM WINDOW IS SIMILAR TO THE GEM THOUGH A BIT FARTHER N THAN THE GEM. BEING ON THE NRN END OF THE MCS...HVY RAINFALL MAY AFFECT PORTIONS OF THE FCST AREA...BUT THAT WILL DEPEND ON THE EVOLUTION/STRUCTURE OF THE MCS. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 503 AM EDT MON JUN 16 2014 SMALL DISTURBANCES WILL PLAGUE MUCH OF THIS PERIOD...WHICH WILL REMAIN DIFFICULT TO TIME. THE BEST CHANCE OF CONVECTION WILL BE NEAR THE WI BORDER. WINDS TUESDAY SHOULD BE LESS THAN 10KTS...BUT THE DIRECTION IS STILL IN QUESTION. THIS IN BECAUSE OF THE VARIED PLACEMENT OF A WEAK SFC LOW ACROSS THE UPPER GREAT LAKES. THE 16/00Z NAM PLACES THIS FEATURE OVER THE KEWEENAW PENINSULA AT 12Z TUESDAY...WHILE THE CANADIAN IS ACROSS THE CENTRAL U.P....AND THE 15/12Z ECMWF IS APPROX 160MI S OF THE NAM. WILL GO WITH A GENERAL BLEND...AND LIKE AS STATED ABOVE WINDS SHOULD BE LESS THAN 10KTS...SO DO NOT EXPECT TOO MANY PROBLEMS WITH THIS SOLUTION BEFORE THE RIDGE PUSHES IN FROM THE NW IN THE AFTERNOON. RH VALUES SHOULD BOTTOM OUT BETWEEN 45 AND 55 PERCENT. OVERALL...LOOK FOR A DIMINISHING TREND TO THE SHOWERS AND THUNDERSTORMS TUESDAY. THE 500MB RIDGE WILL REMAIN JUST W OF THE UPPER GREAT LAKES UNTIL THURSDAY MORNING...AS THE SFC RIDGE STRENGTHENS IT/S HOLD OVER UPPER MI. EXPECT E-NE WINDS TUESDAY NIGHT THROUGH WEDNESDAY NIGHT. LINGERING FOG ACROSS LAKE SUPERIOR SHOULD SLOWLY ERODE FROM N TO S DURING THE DAY WEDNESDAY. UNSETTLED WX WILL LIKELY REMAIN OFF AND ON MAINLY NEAR THE WI BORDER...CLOSER TO THE BETTER MOISTURE. WINDS WILL INCREASE WEDNESDAY NIGHT INTO THURSDAY...IN RESPONSE TO THE INCREASED PRESSURE GRADIENT BETWEEN THE SFC RIDGE OVER THE E HALF OF ONTARIO AND THE NEARING LOW ACROSS NE AND SD. STILL...THE E FLOW SHOULD STILL KEEP TEMPS FROM WARMING MUCH MORE THAN THE MID 70S ACROSS MUCH OF THE CWA...AS 850MB TEMPS LINGER BETWEEN 10-13C. THE SFC LOW OVER S CENTRAL CANADA AND THE N PLAINS THURSDAY AFTERNOON WILL REMAIN NEARLY STATIONARY...BUT WITH A SLIGHT E PUSH AS THE 500MB WAVE OVER THE DAKOTAS AT 00Z FRIDAY KICKS SLIGHTLY NNE TOWARD MN. THE NEXT BEST CHANCE OF WIDESPREAD PRECIP /AT LEAST W AND CENTRAL/ WILL LIKELY BE DURING THE DAY FRIDAY. THERE ARE SOME INDICATIONS THAT E AREAS COULD BE SEVERAL DEGREES WARMER THAN CURRENTLY FCST FRIDAY...IF RAIN/CLOUDS HOLD OFF UNTIL THE MID TO LATE AFTERNOON HOURS. THE SPREAD BETWEEN THE FCST SOLUTIONS IS SIGNIFICANT FOR THIS TIME PERIOD...SO WILL NOT MAKE ANY LARGE CHANGES TO THE ONGOING FCST. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 740 AM EDT MON JUN 16 2014 UNDER A DRY AIR MASS...VFR CONDITIONS WILL PREVAIL TODAY AT KIWD/KCMX/KSAW. TONIGHT...A DISTURBANCE WILL GENERATE A COMPLEX OF SHRA/TSTMS THAT WILL MOVE INTO THE WESTERN GREAT LAKES...AND UPPER MI WILL BE ON THE NRN END OF THE COMPLEX. CONDITIONS WILL LIKELY FALL TO MVFR OVERNIGHT WITH IFR POSSIBLE AT KIWD AS WINDS MAY SWING AROUND TO AN UPSLOPE NW DIRECTION AROUND SUNRISE. WITH HEAVIER PCPN AND POSSIBLE TSTMS MORE LIKELY TO AFFECT KSAW...INCLUDED VCTS LATE. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 537 AM EDT MON JUN 16 2014 WINDS WILL CONTINUE TO DIMINISH ACROSS LAKE SUPERIOR TODAY AS PRES GRADIENT WEAKENS. THESE LIGHTER WINDS...MOSTLY UNDER 20KT...WILL CONTINUE THRU TUE. HOWEVER...DEPENDING ON THE TRACK OF A CLUSTER OF SHRA/TSTMS PASSING THRU WI AND AT LEAST PARTS OF UPPER MI LATE TONIGHT/TUE MORNING...THERE MAY BE LOCALLY HIGHER WINDS FOR A TIME LATE TONIGHT/TUE MORNING. FROM LATE TUE THRU FRI...LAKE SUPERIOR WILL BECOME SITUATED BTWN A HUDSON BAY HIGH AND A LOW PRES TROF SLOWLY ADVANCING ACROSS THE PLAINS. THIS WILL RESULT IN EASTERLY WINDS LATER TUE THRU FRI. WHILE WINDS SHOULD GENERALLY BE UNDER 20KT...THIS TYPE OF PATTERN IS FAVORABLE FOR STRONGER WINDS OVER THE WRN PART OF THE LAKE...ESPECIALLY TOWARD THE MN N SHORE DUE TO COASTAL CONVERGENCE/FUNNELING. OTHERWISE...WINDS OVERALL COULD BE STRONGER DEPENDING ON THE STRENGTH OF THE HIGH PRES AND LOW PRES. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...KF AVIATION...ROLFSON MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
539 AM EDT MON JUN 16 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 537 AM EDT MON JUN 16 2014 WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW THAT THE NEGATIVE TILT SHORTWAVE THAT LIFTED THRU THE UPPER MISSISSIPPI VALLEY YESTERDAY HAS BECOME AN IMPRESSIVE LOOKING MID LEVEL LOW OVER NRN ONTARIO EARLY THIS MORNING. SUBTLE SHORTWAVE ROTATING AROUND THE LOW MANAGED TO SPARK A FEW -SHRA OVER WRN LAKE SUPERIOR/FAR WRN UPPER MI FROM AROUND KIWD TO THE KEWEENAW PENINSULA OVERNIGHT/EARLY THIS MORNING. OTHERWISE...AS EXPECTED SKIES HAVE LARGELY CLEARED ACROSS THE FCST AREA AS MUCH DRIER AIR...ESPECIALLY IN THE MID LEVELS...HAS ADVECTED INTO THE AREA. AT THE VERY LOW-LEVELS...YESTERDAY`S RAINFALL AND DIMINISHING WINDS UNDERNEATH THE MID LEVEL DRYING HAVE RESULTED IN FOG FORMATION OVER A GOOD PORTION OF CNTRL UPPER MI. WITH DECENT WINDS JUST ABOVE THE SFC (KMQT RADAR SHOWS 25KT SW WINDS AT 500FT AGL)...FOG SHOULD QUICKLY DISPERSE WITHIN A COUPLE OF HRS AFTER SUNRISE. HOWEVER...NEAR LAKE MICHIGAN...PATCHY FOG MAY PLAGUE LAKESIDE LOCATIONS INTO THE AFTN HRS. OTHERWISE...LOOKS LIKE A MAINLY SUNNY AND MUCH WARMER DAY IS SHAPING UP. FCST SOUNDINGS INDICATE A DEEP MIXING DAY WITH BOUNDARY LAYER BUILDING TO TOWARD 750MB. THIS YIELDS MAX TEMPS INTO 80-85 RANGE OVER MUCH OF THE AREA...BUT IT WILL BE COOLER NEAR LAKE MICHIGAN WITH PREVAILING S/SW WINDS. A NUMBER OF HIGH RES MODELS INDICATE LAKE BREEZE DEVELOPMENT NEAR LAKE SUPERIOR...AND THIS IS INCREASINGLY INDICATED BY HOURLY RUC13 MODEL RUNS. DEVELOPMENT SHOULD OCCUR LATE ENOUGH IN THE DAY TO STILL ALLOW MOST LOCATIONS NEAR LAKE SUPERIOR TO GET IN ON THE WARMTH TODAY AS WELL. DEEP MIXING WILL AID IN LOWERING DWPTS THIS AFTN. INCORPORATED MIXED LAYER DWPTS INTO THE FCST WHICH RESULTS IN DWPTS FALLING INTO THE MID/UPPER 40S IN THE INTERIOR...AND THIS PUTS MIN RH DOWN AROUND 30PCT. THE DEEP MIXING SHOULD ALSO LEAD TO GUSTY WINDS INTO THE 20-30MPH RANGE FOR A TIME WHERE RH IS LOWEST. FORTUNATELY...YESTERDAYS RAINFALL AND NEAR SATURATED SFC LAYER/DEW FORMATION OVERNIGHT WILL MITIGATE SOME OF THE FIRE WX CONCERNS. ONE LAST ISSUE FOR TODAY IS THE POTENTIAL FOR ISOLD CONVECTION. GFS SHOWS MLCAPE UPWARDS OF AROUND 500J/KG OVER ROUGHLY THE W HALF TODAY WHILE THE NAM IS BIT HIGHER TO 500-900J/KG. THERE IS SUFFICIENT MOISTURE FOR POSSIBLE CONVECTION (A SIMPLE LOOK AT K INDEX SHOWS VALUES UP TO AROUND 30 ON THE GFS AND A LITTLE HIGHER WITH THE NAM). HOWEVER...GIVEN 40-60M HEIGHT RISES AT 500MB TODAY WITH SHORTWAVE RIDGING APPROACHING...WILL HOLD OFF ON INTRODUCING ANY PCPN MENTION. AS OPPOSED TO PREVIOUS DAYS MODEL RUNS...MOST MODELS NOW SHOW A DRY DAY ACROSS THE FCST AREA...FURTHER SUPPORTING THE DRY FCST. THAT SAID...WILL NEED TO KEEP AN EYE ON LAKE SUPERIOR LAKE BREEZE DEVELOPMENT AS THAT COULD TRIGGER ISOLD LATE AFTN CONVECTION. TONIGHT...ATTENTION TURNS TO SHORTWAVE LIFTING NE FROM THE PLAINS. SIGNIFICANT BUILD UP OF INSTABILITY TODAY COMBINED WITH LOW-LEVEL JET DEVELOPING IN RESPONSE TO SHORTWAVE WILL TRIGGER THE DEVELOPMENT OF STRONG CONVECTION SOMEWHERE OVER NE/SD/IA/SRN MN LATER THIS AFTN. THIS CONVECTION WILL LIKELY GROW INTO AN MCS TONIGHT THAT WILL RIDE ENE IN CONJUNCTION WITH ENE TRACKING SHORTWAVE. WHILE SVR THREAT SHOULD PASS S OF THE FCST AREA CLOSER TO MAX INSTABILITY AND INSTABILITY GRADIENT...NOT OUT OF THE QUESTION FOR STRONGER STORMS TO SLIP INTO SRN UPPER MI LATE TONIGHT. FOR NOW...PREFER THE LOOK OF THE 00Z REGIONAL GEM WITH RESPECT TO EXPECTED MCS DEVELOPMENT/MOVEMENT. THIS MODEL BRINGS SHRA/TSRA INTO MAINLY CNTRL/ERN UPPER MI LATE TONIGHT. THE HIGH RES NAM WINDOW IS SIMILAR TO THE GEM THOUGH A BIT FARTHER N THAN THE GEM. BEING ON THE NRN END OF THE MCS...HVY RAINFALL MAY AFFECT PORTIONS OF THE FCST AREA...BUT THAT WILL DEPEND ON THE EVOLUTION/STRUCTURE OF THE MCS. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 503 AM EDT MON JUN 16 2014 SMALL DISTURBANCES WILL PLAGUE MUCH OF THIS PERIOD...WHICH WILL REMAIN DIFFICULT TO TIME. THE BEST CHANCE OF CONVECTION WILL BE NEAR THE WI BORDER. WINDS TUESDAY SHOULD BE LESS THAN 10KTS...BUT THE DIRECTION IS STILL IN QUESTION. THIS IN BECAUSE OF THE VARIED PLACEMENT OF A WEAK SFC LOW ACROSS THE UPPER GREAT LAKES. THE 16/00Z NAM PLACES THIS FEATURE OVER THE KEWEENAW PENINSULA AT 12Z TUESDAY...WHILE THE CANADIAN IS ACROSS THE CENTRAL U.P....AND THE 15/12Z ECMWF IS APPROX 160MI S OF THE NAM. WILL GO WITH A GENERAL BLEND...AND LIKE AS STATED ABOVE WINDS SHOULD BE LESS THAN 10KTS...SO DO NOT EXPECT TOO MANY PROBLEMS WITH THIS SOLUTION BEFORE THE RIDGE PUSHES IN FROM THE NW IN THE AFTERNOON. RH VALUES SHOULD BOTTOM OUT BETWEEN 45 AND 55 PERCENT. OVERALL...LOOK FOR A DIMINISHING TREND TO THE SHOWERS AND THUNDERSTORMS TUESDAY. THE 500MB RIDGE WILL REMAIN JUST W OF THE UPPER GREAT LAKES UNTIL THURSDAY MORNING...AS THE SFC RIDGE STRENGTHENS IT/S HOLD OVER UPPER MI. EXPECT E-NE WINDS TUESDAY NIGHT THROUGH WEDNESDAY NIGHT. LINGERING FOG ACROSS LAKE SUPERIOR SHOULD SLOWLY ERODE FROM N TO S DURING THE DAY WEDNESDAY. UNSETTLED WX WILL LIKELY REMAIN OFF AND ON MAINLY NEAR THE WI BORDER...CLOSER TO THE BETTER MOISTURE. WINDS WILL INCREASE WEDNESDAY NIGHT INTO THURSDAY...IN RESPONSE TO THE INCREASED PRESSURE GRADIENT BETWEEN THE SFC RIDGE OVER THE E HALF OF ONTARIO AND THE NEARING LOW ACROSS NE AND SD. STILL...THE E FLOW SHOULD STILL KEEP TEMPS FROM WARMING MUCH MORE THAN THE MID 70S ACROSS MUCH OF THE CWA...AS 850MB TEMPS LINGER BETWEEN 10-13C. THE SFC LOW OVER S CENTRAL CANADA AND THE N PLAINS THURSDAY AFTERNOON WILL REMAIN NEARLY STATIONARY...BUT WITH A SLIGHT E PUSH AS THE 500MB WAVE OVER THE DAKOTAS AT 00Z FRIDAY KICKS SLIGHTLY NNE TOWARD MN. THE NEXT BEST CHANCE OF WIDESPREAD PRECIP /AT LEAST W AND CENTRAL/ WILL LIKELY BE DURING THE DAY FRIDAY. THERE ARE SOME INDICATIONS THAT E AREAS COULD BE SEVERAL DEGREES WARMER THAN CURRENTLY FCST FRIDAY...IF RAIN/CLOUDS HOLD OFF UNTIL THE MID TO LATE AFTERNOON HOURS. THE SPREAD BETWEEN THE FCST SOLUTIONS IS SIGNIFICANT FOR THIS TIME PERIOD...SO WILL NOT MAKE ANY LARGE CHANGES TO THE ONGOING FCST. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 136 AM EDT MON JUN 16 2014 DRIER MID LEVEL AIR MOVING IN BEHIND A FRONTAL SYSTEM HAS BROUGHT CLEARING SKIES ACROSS MOST OF UPPER MI. HOWEVER...ENOUGH LOW LEVEL MOISTURE HAS LINGERED OVER CENTRAL UPPER MI SO THAT SOME LOW CLOUDS AND FOG HAVE DEVELOPED AT KSAW AS WINDS HAVE DIMINISHED. ALTHOUGH WINDS VEERING MORE TO THE SW MAY LIMIT THE POTENTIAL FOR DENSE FOG...EXPECT THE LOWER CIGS TO LINGER UNTIL DAYTIME MIXING TAKES OVER THIS MORNING. SOME FOG HAS ALSO DEVELOPED AT KCMX...BUT EXPECT THIS TO BE SHORT-LIVED AS A SLIGHT INCREASE IN SW WINDS WILL PROVIDE SOME MIXING. EXPECT VFR CONDITIONS AT KIWD OVERNIGHT AS S TO SW WINDS KEEP BETTER MIXING GOING THERE. VFR CONDITIONS WILL BE THE RULE AT ALL TERMINALS TODAY INTO THE EVENING HRS. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 537 AM EDT MON JUN 16 2014 WINDS WILL CONTINUE TO DIMINISH ACROSS LAKE SUPERIOR TODAY AS PRES GRADIENT WEAKENS. THESE LIGHTER WINDS...MOSTLY UNDER 20KT...WILL CONTINUE THRU TUE. HOWEVER...DEPENDING ON THE TRACK OF A CLUSTER OF SHRA/TSTMS PASSING THRU WI AND AT LEAST PARTS OF UPPER MI LATE TONIGHT/TUE MORNING...THERE MAY BE LOCALLY HIGHER WINDS FOR A TIME LATE TONIGHT/TUE MORNING. FROM LATE TUE THRU FRI...LAKE SUPERIOR WILL BECOME SITUATED BTWN A HUDSON BAY HIGH AND A LOW PRES TROF SLOWLY ADVANCING ACROSS THE PLAINS. THIS WILL RESULT IN EASTERLY WINDS LATER TUE THRU FRI. WHILE WINDS SHOULD GENERALLY BE UNDER 20KT...THIS TYPE OF PATTERN IS FAVORABLE FOR STRONGER WINDS OVER THE WRN PART OF THE LAKE...ESPECIALLY TOWARD THE MN N SHORE DUE TO COASTAL CONVERGENCE/FUNNELING. OTHERWISE...WINDS OVERALL COULD BE STRONGER DEPENDING ON THE STRENGTH OF THE HIGH PRES AND LOW PRES. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...KF AVIATION...JLB MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
101 AM EDT MON JUN 16 2014 .AVIATION... //DISCUSSION... 00Z SOUNDING FROM DTX REVEALED A VERY DRY AND STABLE PROFILE ACROSS SOUTHEAST MI. EXPECT THE SHOWERS AND THUNDERSTORMS TO CONTINUE TO STRUGGLE AS THEY MOVE EAST. WHILE THERE WILL BE SOME INCREASE IN MOISTURE AND SOME MODEST INSTABILITY...THE BEST FORCING WILL CONTINUE TO MOVE AWAY FROM THE AREA. THERE IS A WEAK SHORTWAVE ACROSS INDIANA THAT WILL BE A CHANCE OF A SHOWER FOR THE DETROIT AREA TAFS. OTHERWISE...THE MOISTURE WILL BRING JUST VFR CIGS TO THE TAF CITES INTO THE MORNING HOURS. FROM 13Z-17Z ENOUGH DRIER AIR WILL FILTER IN FROM NORTH TO SOUTH TO BRING SCATTERED SKIES THROUGH THE MONDAY AFTERNOON. FOR DTW...BEST POTENTIAL FOR A SHOWER AND POSSIBLY A THUNDERSTORM WILL BE BETWEEN 08Z AND 12Z. THAT IS ALSO WHEN CIGS ARE EXPECTED TO BE AROUND THE 5000 FEET. //DTW THRESHOLD THREATS... * MODERATE CONFIDENCE WITH CEILINGS AT 5000 FEET BETWEEN 09Z AND 16Z. * LOW CONFIDENCE IN THUNDERSTORMS BETWEEN 09Z AND 12Z. && .PREV DISCUSSION...ISSUED 902 PM EDT SUN JUN 15 2014 UPDATE... SHOWERS AND THUNDERSTORMS ACROSS NORTHERN LOWER AND SOUTHERN LAKE MI HAVE STRUGGLED TO HOLD TOGETHER WHILE MOVING EAST. NOT TOO SURPRISING GIVING THE FORCING PEELING OFF TO THE NORTH ACROSS THE FAR NORTHWEST PART OF THE GREAT LAKES. 00Z DTX SOUNDING WAS STILL VERY DRY AND HAD A STRONG CAP BETWEEN 800 AND 700 MBS. IT WILL TAKE QUITE A BIT OF ADVECTION TO OVERCOME THAT...AND THIS SYSTEM DOES NOT HAVE THAT. WILL LOWER POPS TO SCATTERED/CHANCE. EXPECT THE BEST CHANCE TO BE NEAR TRI CITIES WITH THE MAIN SHORTWAVE INFLUENCE. THERE IS A PIECE OF ENERGY THAT WAS NEAR THE IN/IL BOARDER AND WILL GO SLIGHTLY HIGHER CHANCE POPS FOR FAR SE LOWER. ALSO WITH THE GIVEN ATMOSPHERE...WILL LOWER THE THREAT OF THUNDERSTORMS. ALL OF THE AFTERNOON UPDATED HI RES MODELS WERE IN LINE WITH THIS IDEA AS WELL. PREV DISCUSSION...ISSUED 407 PM EDT SUN JUN 15 2014 SHORT TERM...TONIGHT A LINE OF SHOWER AND THUNDERSTORMS HAVE INITIATED THIS AFTERNOON OVER PORTIONS OF WISCONSIN ALONG A CONVERGENT STREAMLINE. THIS CONVERGENCE ZONE HAS GOOD CONTINUITY WITH A ZONE OF ENHANCED ABSOLUTE VORTICITY IN THE LATEST RUC OUTPUT. THE CONVERGENCE STREAMER AND RIBBON OF FORCING IS TIED TO THE ENTRANCE REGION OF MIDLEVEL JET STRUCTURE LIFTING NORTHWARD INTO THE SYNOPTIC LOW PRESSURE SYSTEM DEEPENING OVER NORTHERN MINNESOTA. MODEL DATA SUPPORTS THE ENHANCED LINE OF CONVERGENCE OR MIDLEVEL INFLECTION AXIS TO CAST OFF...SHEDDING DUE EASTWARD TONIGHT AS THE LOW LIFTS INTO NORTHWESTERN ONTARIO. THE TONIGHT PERIOD THEN DISTILLS DOWN TO WHAT THE AREAL COVERAGE OF PRECIPITATION WILL BE AS THE AFOREMENTIONED AXIS TRACKS THROUGH THE AREA. WHAT IS COMPLICATING THIS SETUP IS THE VERY STABLE ATMOSPHERE IN PLACE THIS AFTERNOON WITH A SUBSIDENCE INVERSION IN THE 6-12 KFT LAYER. COMBINE THIS STABLE LAYER WITH A VERY DRY NEAR SURFACE ENVIRONMENT...SURFACE DEWPOINT DEPRESSIONS ON THE ORDER OF 30 DEGREES...AND THE SUSPICION IS MUCH OF THE LIFT WILL GO INTO SATURATING THE COLUMN. THE CONVECTION ALLOWING MODELS ARE SHOWING A REAL STRUGGLE WITH PRECIPITATION COVERAGE. PROBABLY THE BEST THING GOING FOR THE SETUP ACROSS THE SOUTHERN CWA IS THE POTENTIAL FOR THE RIBBON OF MOISTURE TO ALIGN WITH THE MEAN FLOW LATE TONIGHT. THIS IS BY NO MEANS AN ENDORSEMENT...MORE OF A COMMENT ON THE LOW CONFIDENCE/HIGH UNCERTAINTY. FOR THOSE REASONS...WILL NOT DEVIATE FROM THE INHERITED POP GRIDS. IT IS DIFFICULT TO DECIDE ON THIS BEING A SCATTERED OR NUMEROUS SHOWER TYPE EVENT. TIME OF YEAR AND CONVECTIVE INSTABILITY REQUIRES A THUNDER MENTION...ALTHOUGH THERE IS NO SIGNAL FOR A HIGH AMOUNT OF EXPECTED LIGHTNING. HRRR ALONG WITH 12Z WRF-NMM MOVED TIMING UP A HAIR...LOOKING AT TIME WINDOW FOR PRECIPITATION MAINLY BETWEEN 3-9Z. LONG TERM...MONDAY THROUGH SATURDAY DEFINED MOISTURE PLUME ATTENDANT TO A WEAK FRONTAL BOUNDARY WILL EASE SOUTH AND EAST MONDAY MORNING AS SLIGHTLY LOWER HEIGHTS STREAM BY TO THE NORTH. OVERALL TIMING AND POSITIONING OF THESE FEATURES CONTINUE TO SUGGEST THERE WILL REMAIN A WINDOW EARLY IN THE DAY FOR ADDITIONAL SHOWER/THUNDERSTORM DEVELOPMENT ROUGHLY SOUTHEAST OF A HOWELL TO SANDUSKY LINE. MORE SUBSTANTIAL DRYING THROUGH THE COLUMN BY AFTERNOON WITHIN A BACKGROUND OF WEAK MID LEVEL SUBSIDENCE WILL GREATLY LIMIT THE PROSPECTS FOR DIURNALLY DRIVEN CONVECTION DURING THE AFTERNOON/EVENING...DESPITE THE PRESENCE OF A STEEP LOW LEVEL LAPSE RATE ENVIRONMENT. A WELL MIXED AND DRYING 800-925 MB LAYER WITH AT LEAST PARTIAL SUNSHINE WILL ALLOW TEMPERATURES TO RESPOND ACCORDINGLY. HIGHS OF LOWER AND MIDDLE 80S AREAWIDE. RENEWED STRENGTHENING OF THE DOWNSTREAM SOUTHWEST FLOW WILL SEND THE EXISTING HIGHER THETA-E AIR MASS BACK NORTHEASTWARD AND INTO SE MICHIGAN MONDAY NIGHT AND TUESDAY. THE ADVANCING WARM FRONTAL SLOPE WILL SUPPORT THE MENTION OF SHOWERS AND THUNDERSTORMS BEGINNING LATE MONDAY NIGHT AS MID LEVEL INSTABILITY INCREASES WITH THE MOISTURE ADVECTION. THERE MAY ALSO BE A PERIOD OF WEAK ISENTROPIC ASCENT. IN ADDITION...POSSIBLE NOCTURNAL MAINTENANCE AND DOWNSTREAM PROPAGATION OF CONVECTIVE DEVELOPMENT OVER THE UPPER MS VALLEY WILL REQUIRE ATTENTION...12Z MODEL SUITE PROVIDING A MIXED SIGNAL ON THE POTENTIAL FOR THIS ACTIVITY TO ENTER A PORTION OF THE AREA. UNCERTAINTY IN THE DETAILS OF ANY MCS/MCV REMNANTS PLAY A DEFINITIVE ROLE IN DEFINING THE PROSPECTS FOR CONVECTION ON INTO TUESDAY. A MORE SIZABLE CLOUD/RAIN LADEN COMPLEX ARRIVING EARLY IN THE DAY COULD DAMPEN/DELAY THE DEGREE OF DESTABILIZATION. CONVERSELY...A LATE DAY ARRIVAL COULD BE OPPORTUNE FOR ANCHORING A MORE ORGANIZED CONVECTIVE EPISODE. THE COMBINATION OF WARM AIR ADVECTION AND SOME INCREASE IN THE UPPER HEIGHT FIELD WOULD SUPPORT HIGHS OF UPPER 80S...ABSENT OF A DISRUPTION OF THE HEATING CYCLE BY EARLY DAY ACTIVITY. EXTENDED FORECAST WILL LARGELY HINGE ON WHAT HAPPENS WITH THE MONDAY/TUESDAY CONVECTION. MODELS STILL ADVERTISING A BOUNDARY SETTING UP OVER THE AREA ALONG WITH AN UPPER LEVEL LOW MOVING ACROSS THE NORTHERN CONUS. WITH THAT...THERE WILL BE THE CONTINUAL CHANCE FOR RAIN/THUNDERSTORMS THROUGH THE REMAINDER OF THE WEEK AND POSSIBLY INTO THE BEGINNING OF THE WEEKEND. ALL IN ALL...AN ACTIVE WEATHER PATTERN LOOKS TO BE IN STORE FOR SOUTHEAST MICHIGAN. MARINE... A GUSTY SOUTHEAST WIND THROUGH THE EVENING PERIOD IN ADVANCE OF A SURFACE TROUGH. GUSTS WILL REMAIN AT OR BELOW 20 KNOTS GIVEN THE HIGHER DEGREE OF STABILITY OVER THE LAKES. THIS TROUGH WILL BRING WITH IT A GOOD CHANCE OF THUNDERSTORMS. WINDS WILL DECREASE ON MONDAY AS WEAK HIGH PRESSURE EXPANDS ACROSS THE GREAT LAKES. A WARM FRONT IS THEN FORECAST TO LIFT INTO THE REGION MONDAY NIGHT AND REMAIN NEARLY STATIONARY OVER THE GREAT LAKES REGION INTO MID WEEK. THIS FRONT MAY TRIGGER SEVERAL ROUNDS OF THUNDERSTORMS DURING THE MID WEEK PERIOD. SOME OF WHICH MAY BE STRONG TO SEVERE. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...NONE. LAKE ST CLAIR...NONE. MI WATERS OF LAKE ERIE...NONE. && $$ AVIATION.....RBP UPDATE.......RBP SHORT TERM...CB LONG TERM....MR/SS MARINE.......MR YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
925 PM CDT Tue Jun 17 2014 .UPDATE: Issued at 906 PM CDT Tue Jun 17 2014 Latest HRRR model run keeps any convection north of our forecast area through 12Z Wednesday, although the latest NAM model still has convection across northeast MO and west central IL late tonight. Will keep slight chance pops at least across the extreme northern portion of the forecast area late tonight. Unseasonably warm low temperatures are expected again tonight, about 10 degrees above normal with continued southerly winds and high surface dew points. GKS && .SHORT TERM: (Through Late Tonight) Issued at 330 PM CDT Tue Jun 17 2014 The primary concern tonight is whether we may see any showers or thunderstorms across far northern sections of the CWA. The main focus remains the quasi-stationary boundary stretching from eastern Nebraska across Iowa into the lower Great Lakes region. Any of this activity should have an eastward component of motion, however the possibility of scenario similar to late last night/early this morning is within the realm of possibilities. That is, a remnant outflow boundary could push south in to the area and lift associated with the southwesterly LLJ on its flank could result in some showers and thunderstorms. Also mid level temperatures are forecast to cool a tad overnight and steep lapse rates will be present so there is even some potential for high based activity in the same general location. I have added a low pop across northeast MO and west central IL to account for the possibility but with low confidence. Elsewhere a mild night is on tap with lows in the 70s. Glass .LONG TERM: (Wednesday through Next Tuesday) Issued at 330 PM CDT Tue Jun 17 2014 Another seasonably hot and humid day is on tap for the area on Wednesday. Tempeatures haven`t gotten as warm today as initially anticipated and see no reason to go much warmer than some variation of upper 80s-lower 90s since temperatures aloft are actually forecast to cool slightly. The models continue to generate either some spotty or light QPF on Wednesday afternoon and this might be a signal of the anticipated increasing chance of isolated diurnally driven thunderstorms I have alluded to the last several days. Mid level cooling on the order of 2-3 degrees will result in little CIN during peak afternoon heating, it is just a question of impetus. Also there is a signal that some remnant boundary may be flirting around across west central and south central IL. As a result I have some low pops going for a dual fold threat but there is a good degree of uncertainty. The threat of showers and thunderstorms gradually ramps up on Wednesday night and especially Thursday into Friday. On Wednesday night due to potential for MCS remnants progressing into the northern CWA. On Thursday we see a more focused zone of moisture/instability progress into the area ahead of the encroaching cold front and continued mid level cooling as the ridging aloft breaks down. And by Friday there are indications that this front makes some progress into the CWA as ridging aloft breaks down further and flow aloft becomes more westerly. This westerly flow also contains weak impulses contributing to large scale support. This front may be lingering either just to our north or across parts of the CWA into Saturday and Sunday with a wavy structure. Sunday into early next week, an upper low/trof in the vicinity of the central U.S./Canadian border will track sewd through the Great Lakes/Ohio Valley region sending another front into the CWA that will slowly move southward keeping an ongoing threat of showers and thunderstorms. Glass && .AVIATION: (For the 00z TAFs through 00z Wednesday Evening) Issued at 628 PM CDT Tue Jun 17 2014 VFR conditions are expected at terminals through Wednesday evening with possible exceptions of developing cu with bases around 3000 feet tomorrow at KCOU and KUIN as well as possibility of thunderstorms. Not confident enough in thunderstorms affecting any one of the terminals at this time so left mention out for now...though thunderstorms are possible across the entire area. Convection may get some help initiating during the day tomorrow near an outflow boundar(ies) from overnight storms tonight. However...southward penetration of this aforementioned outflow boundary is highly uncertain at this time. Otherwise...TAF sites can expect southerly winds lightening up overnight with winds picking back up and becoming gusty around mid morning on Wednesday. Specifics for KSTL: VFR conditions are expected at KSTL through Wednesday evening with possible exception of the possibility of thunderstorms on Wednesday afternoon. Not confident enough in thunderstorms affecting the terminal at this time so left mention out for now...though thunderstorms are possible. Convection may get some help initiating during the day tomorrow near an outflow boundar(ies) from overnight storms tonight. However...southward penetration of this aforementioned outflow boundary is highly uncertain at this time. Otherwise...Lambert Field can expect southerly winds lightening up overnight with winds picking back up and becoming gusty around mid morning on Wednesday. Gosselin && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
610 PM MDT TUE JUN 17 2014 .UPDATE... WE ARE MAINTAINING THE TORNADO WATCH OVER CUSTER...FALLON...AND CARTER COUNTIES IN SOUTHEAST MT FOR NOW. THE LOW-LEVEL BOUNDARY THAT WAS RESPONSIBLE FOR THE FIRST ROUND OF STORMS HASN/T MOVED MUCH...AND IN FACT VISIBLE SATELLITE IMAGES AS OF 00 UTC REVEAL IT HAS MOVED BACK WESTWARD A BIT. THOSE SAME IMAGES SHOW JUST A BIT OF AGITATION TO THE CUMULUS ALONG THE BOUNDARY. SUBSIDENCE BEHIND THE EARLIER STORMS MIGHT PREVENT NEW DEVELOPMENT...BUT A CONDITIONAL RISK OF MORE SEVERE STORMS EXISTS SINCE IT IS STILL QUITE UNSTABLE THERE WITH MLCAPE UP TO 2000 J/KG IN PLACE BASED ON SPC MESOANALYSIS DATA. PLUS...THERE IS SOME SUGGESTION IN 12 UTC SSEO GUIDANCE AND RECENT HRRR DATA THAT THE CONVECTION OVER SOUTH CENTRAL MT AT 00 UTC MAY INTENSIFY AS IT LIFTS NORTHEAST- WARD INTO SOUTHEASTERN MT THE NEXT FEW HOURS. SCHULTZ && .SHORT TERM...VALID FOR WED AND THU... CONVECTION ALREADY GOING OVER THE SOUTHEAST. BOUNDARY SITTING JUST EAST OF MILES CITY WITH STRONG EAST WINDS AT BAKER. THUNDERSTORMS HAVE FORMED ALONG THAT BOUNDARY AND THIS SHOULD BE THE FOCUS POINT FOR INITIATION THIS AFTERNOON AND EVENING. ADEQUATE SHEAR AND CAPE FOR DEEP CONVECTION WITH STRONGLY ROTATING UPDRAFTS. MODELS SWING SEVERAL WAVES OF CONVECTION THROUGH THE SOUTHEAST AS A STRONG JET ROTATES AROUND THE DEEP UPPER LOW OVER IDAHO. LOW LCL HEIGHTS WOULD SUPPORT THE POTENTIAL FOR TORNADOES. PRECIPITABLE WATER AMOUNTS WERE RIGHT AROUND AN INCH AND A QUARTER OVER THE EAST AND THEREFORE RAINFALL RATES SHOULD BE VERY HIGH. TRAINING OF ECHOES WILL BE A CONCERN AND THUS WILL MAINTAIN THE FLASH FLOOD WATCH. FARTHER WEST...THE STRONG JET MENTIONED ABOVE WILL DRIVE CONVECTION THROUGH THE NIGHT. THE GFS CAME IN WITH A LARGE SWATH OF NEARLY AN INCH OF QPF OVERNIGHT FROM BILLINGS WESTWARD. THIS MODEL WAS A BIT OF AN OUTLIER AS THE EC AND NAM WERE NOT NEARLY THAT HEAVY WITH PRECIPITATION TOTALS. THAT BEING SAID...THE RAP MODEL SHOWED SIGNS OF SUPPORTING THE GFS WITH THE LAST COUPLE OF RUNS. BUMPED POPS OVERNIGHT OVER CENTRAL AND WESTERN ZONES. INSTABILITY WAS NOT NEARLY AS DEEP OVER CENTRAL AND WESTERN ZONES...BUT ENOUGH DYNAMICS FOR THE POTENTIAL FOR THUNDERSTORMS. WILL KEEP MENTION OF THUNDERSTORMS THROUGH THE NIGHT BUT NOT EXPECTING SEVERE WEATHER IN THESE LOCATIONS. THE WESTERN UPPER LOW SHIFTS INTO NORTHERN MONTANA WEDNESDAY AFTERNOON AND THIS PUTS THE FORECAST AREA IN DOWNSLOPE FLOW. THIS SHOULD DRY THINGS OUT SOME. THAT BEING SAID...STRONG WRAP AROUND FORCING WORKS INTO WESTERN AND CENTRAL ZONES THROUGH THE DAY AND EVEN INTO THE NIGHT AS THE LOW REMAINS NEARLY STATIONARY. THE EAST WILL BE IN A STRONG DRY SLOT. WINDS WILL KICK UP WEDNESDAY NIGHT. THURSDAY LOOKS TO BE SIMILAR TO WEDNESDAY...ALTHOUGH JUST A BIT WARMER. WRAP AROUND SHOWERS WILL AFFECT WESTERN AND CENTRAL ZONES AND AS THE UPPER LOW SLOWLY PULLS EAST...THIS PRECIPITATION WILL WORK INTO THE EAST. TWH .LONG TERM...VALID FOR FRI...SAT...SUN...MON...TUE... THE UPPER LOW THAT IS CURRENTLY OVER IDAHO WILL SLOWLY MOVE NORTHEAST AND BE OVER SOUTHERN CANADA BY FRIDAY PROVIDING FOR A NORTHWEST FLOW ALOFT ACROSS OUR FORECAST AREA. THIS WILL BE SHORT- LIVED AS RIDGING WILL BUILD OVER THE AREA LATE IN THE DAY CONTINUING THROUGH SUNDAY AS AN UPPER LOW AND TROUGH MOVE ONTO THE PACIFIC NORTHWEST COAST WITH LITTLE MOVEMENT EASTWARD. THE TROUGH AND UPPER LOW WILL DIG INTO NEVADA BY MONDAY WHICH WILL BUILD THE RIDGE STRONGER OVER THE NORTHERN ROCKIES. A FEW DISTURBANCES WILL MOVE ACROSS THE FORECAST AREA THROUGHOUT THE EXTENDED PERIOD BRINGING A CHANCE FOR SHOWERS AND THUNDERSTORMS EACH AFTERNOON/EVENING. TEMPERATURES WILL BE ABOVE NORMAL WITH READINGS IN THE LOWER TO MIDDLE 80S THROUGH THE PERIOD. HOOLEY && .AVIATION... MOSTLY CLOUDY SKIES ALONG WITH SCATTERED SHOWERS AND THUNDERSTORMS CAN BE EXPECTED THIS EVENING. ANY THUNDERSTORM WILL BE CAPABLE OF PRODUCING HEAVY RAIN RESULTING IN LOCAL MVFR TO IFR CONDITIONS. IN ADDITION...SEVERE THUNDERSTORMS ARE POSSIBLE THIS EVENING ALONG AND EAST OF A LINE FROM HYSHAM TO ASHLAND. THESE THUNDERSTORMS WILL BE CAPABLE OF PRODUCING LARGE HAIL...WIND GUSTS IN EXCESS OF 65KTS...AS WELL AS THE POSSIBILITY OF AN ISOLATED TORNADO. THE THREAT OF SEVERE WEATHER IS EXPECTED TO DIMINISH BY LATE EVENING. MOUNTAIN OBSCURATIONS CAN BE EXPECTED AT TIMES THROUGH TONIGHT. HOOLEY && .PRELIMINARY POINT TEMP/POPS... WED THU FRI SAT SUN MON TUE ----------------------------------------------------------- BIL 048/066 049/073 051/081 054/085 056/083 055/084 058/085 63/T 44/T 21/U 12/T 23/T 33/T 32/T LVM 040/060 042/071 045/078 047/080 048/079 048/081 050/080 57/T 53/T 11/U 23/T 33/T 33/T 32/T HDN 049/068 048/074 050/083 053/088 056/085 056/085 058/087 73/T 34/T 21/U 11/U 23/T 33/T 32/T MLS 053/070 049/071 052/081 055/085 058/084 057/085 060/085 84/T 34/T 32/T 11/U 22/T 23/T 32/T 4BQ 052/070 048/072 051/081 053/085 056/084 055/084 058/085 73/T 44/T 31/B 11/U 22/T 23/T 32/W BHK 054/069 048/068 049/076 051/081 054/080 054/080 057/081 +5/T 34/T 42/T 11/U 22/T 23/T 32/W SHR 045/065 043/071 047/080 049/084 052/082 052/083 055/083 63/T 33/T 21/U 12/T 23/T 33/T 32/T && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...FLASH FLOOD WATCH IN EFFECT UNTIL 6 AM MDT WEDNESDAY FOR ZONES 32-33-37. TORNADO WATCH 311 IN EFFECT UNTIL 8 PM MDT THIS EVENING FOR ZONES 32-33-37. WY...NONE. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS HASTINGS NE
647 PM CDT TUE JUN 17 2014 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 315 PM CDT TUE JUN 17 2014 MAP ANALYSIS INDICATES A CLOSED UPPER TROPOSPHERIC LOW OVER THE NORTHWESTERN CONUS...AND A RIDGE OVER THE EAST. ENHANCED UPPER TROPOSPHERIC FLOW EXTENDS FROM THE SOUTHWESTERN CONUS...NORTHEAST INTO THE CENTRAL AND NORTHERN PLAINS...AND THEN FARTHER NORTHEAST INTO THE GREAT LAKES REGION AND SOUTHEASTERN CANADA. UPPER TROPOSPHERIC FLOW OVER OUR AREA MAXES OUT AT AROUND 55KTS NEAR 37000FT AGL PER 12Z SOUNDING DATA FROM KLBF AND KOAX. WATER VAPOR IMAGERY INDICATES ENHANCED UPPER TROPOSPHERIC MOISTURE EXTENDS FROM THE SOUTHERN PLAINS INTO THE GREAT LAKES REGION...AS WELL AS OVER PORTIONS OF THE ROCKY MOUNTAIN RANGE. AT THE SURFACE A STATIONARY BOUNDARY IS NOTED EXTENDING FROM NORTH CENTRAL NEBRASKA INTO SOUTHWESTERN NEBRASKA AND THE CENTRAL HIGH PLAINS. IN ADDITION...A DRY LINE IS NOTED EXTENDING ACROSS PORTIONS OF WESTERN KANSAS. GUIDANCE SUGGESTS THE UPPER TROPOSPHERIC LOW OVER THE NORTHWESTERN CONUS WILL SLOWLY DRIFT NORTHEAST THROUGH THE NEXT 24 HOURS...LIKELY POSITIONING ITSELF OVER NORTHERN MONTANA BY 00Z THURSDAY. AN UPPER TROPOSPHERIC SHORT WAVE IS ALSO EXPECTED TO SWING TO THE SOUTH OF THE LOW AND BEGIN MOVING INTO THE CENTRAL HIGH PLAINS BY 00Z THURSDAY. AT THE SURFACE...THE STATIONARY BOUNDARY MAY BEGIN TO MEANDER SLIGHTLY SOUTHEAST OR NORTHWEST AS AN AREA OF LOW BAROMETRIC PRESSURE ORGANIZES OVER THE CENTRAL HIGH PLAINS...WHICH MAY RESULT IN PERIODIC NORTHWESTERLY LOWER TROPOSPHERIC FLOW OVER WEST/NORTHWESTERN PORTIONS OF OUR CWA DURING THE DAY WEDNESDAY...BUT FOR THE MOST PART LOWER TROPOSPHERIC FLOW IS EXPECTED TO REMAIN FROM THE SOUTH ACROSS MUCH OF OUR CWA THROUGH THE NEXT 24 HOURS. AN OVERALL LACK IN OMEGA SHOULD PROMOTE DRY CONDITIONS ACROSS OUR AREA THIS AFTERNOON AND EVENING. THE HRRR DOES INDICATE SOME VERY ISOLATED CONVECTION OVER WESTERN NEBRASKA LATE THIS AFTERNOON INTO THIS EVENING AS THE CONVECTIVE TEMPERATURE IS REACHED...AND THE 4KM WRF-NMM INDICATES ISOLATED TO SCATTERED CONVECTION OVER SOUTHEASTERN NEBRASKA AND NORTHEASTERN KANSAS FOR THE SAME REASON. SO ALTHOUGH ISOLATED CONVECTIVE ACTIVITY CERTAINLY CANNOT BE RULED ACROSS THE REGION THIS AFTERNOON AND EVENING...THE PROBABILITY OF ANY ONE LOCATION ACTUALLY OBSERVING THIS ACTIVITY IS TOO LOW FOR INSERTION INTO THE FORECAST AND AS A RESULT...WILL MAINTAIN THE DRY FORECAST FOR OUR CWA FOR THIS AFTERNOON AND EVENING. IN THE OFF CHANCE A THUNDERSTORM CAN GET GOING...IT WOULD HAVE 2000-3000J/KG 0-1KM MLCAPE AND ~35KTS DEEP LAYER BULK SHEAR TO WORK WITH...SO CERTAINLY LARGE HAIL AND STRONG THUNDERSTORM WIND GUSTS COULD RESULT...BUT AGAIN THE PROBABILITY OF SUCH ACTIVITY BEING REALIZED TO TOO LOW FOR INSERTION INTO THE FORECAST AND HWO AT THIS TIME. DURING THE OVERNIGHT HOURS TONIGHT...A 60-70KT LOW LEVEL JET AXIS JUST ABOVE THE BOUNDARY LAYER IS EXPECTED TO DEVELOP FROM CENTRAL KANSAS INTO SOUTHEASTERN NEBRASKA. ALTHOUGH THE NORTHWESTERN PERIPHERY OF THIS JET AXIS WILL LIKELY CLIP OUR CWA...IT APPEARS THE BULK OF ANY MOISTURE CONVERGENCE WILL REMAIN TO OUR EAST...AND THE PRIMARY AXIS OF THERMAL ADVECTION WILL REMAIN TO OUR SOUTHEAST. GIVEN ALL THIS...OPTED TO KEEP OUR FORECAST DRY TONIGHT THROUGH THE MORNING HOURS ON WEDNESDAY AS WELL. HEADING INTO WEDNESDAY AFTERNOON...SYNOPTIC-SCALE OMEGA SHOULD INCREASE SOMEWHAT ACROSS THE REGION AS THE UPPER TROPOSPHERIC SHORT WAVE MOVES INTO THE CENTRAL HIGH PLAINS. THIS INCREASING OMEGA...WORKING IN CONCERT WITH LOWER TROPOSPHERIC CONVERGENCE AND FORCING ALONG THE MEANDERING BAROCLINIC ZONE...AS WELL AS NEAR- ZERO CIN ACROSS MUCH OF THE REGION BY LATE AFTERNOON...SHOULD BE SUFFICIENT FOR AT LEAST SOME ISOLATED CONVECTION BY LATE AFTERNOON AND EARLY EVENING. ONE MIGHT THINK LOCATIONS IN THE VICINITY OF THE LOWER TROPOSPHERIC BAROCLINIC ZONE WILL HAVE A BETTER CHANCE AT OBSERVING CONVECTION...BUT QPF FIELDS FROM VARIOUS MODELS SUGGEST OUR SOUTHERN CWA STANDS A BETTER CHANCE AT OBSERVING CONVECTION DUE TO LOWER CIN VALUES. REALLY HARD TO SAY ONE LOCATION HAS A BETTER CHANCE OVER ANOTHER...SO WENT AHEAD AND BLANKETED THE ENTIRE CWA WITH ~20% POPS BETWEEN 21Z WEDNESDAY AND 00Z THURSDAY. SHOULD DEEP CONVECTION BE REALIZED ACROSS THE AREA WEDNESDAY AFTERNOON AND EVENING...0-1KM MLCAPE VALUES OF 2000-3000J/KG ARE EXPECTED TO ACCOMPANY DEEP LAYER BULK SHEAR VALUES OF 20-30KTS. GIVEN ALL THIS...WILL GO AHEAD AND CONTINUE TO OUTLOOK THE AREA FOR ISOLATED SEVERE WEATHER STARTING LATE WEDNESDAY AFTERNOON. LITTLE CHANGE IN THE LOWER TROPOSPHERIC AIR MASS WILL PROMOTE SIMILAR TEMPERATURE READINGS TONIGHT WHEN COMPARED TO EARLY THIS MORNING...WITH OVERNIGHT LOWS IN THE 60S TO NEAR 70 CURRENTLY FORECAST ACROSS THE CWA. SIMILAR TEMPERATURE READINGS ARE ALSO EXPECTED WEDNESDAY WHEN COMPARED TO TODAY...WITH WEDNESDAY AFTERNOON HIGHS IN THE 90S CURRENTLY EXPECTED. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 315 PM CDT TUE JUN 17 2014 MAIN FORECAST CONCERNS WILL BE CHANCES FOR THUNDERSTORMS THROUGH MUCH OF THE PERIOD AND TEMPERATURES THROUGH THE PERIOD. A COLD FRONT IS EXPECTED TO MOVE MOST OF THE WAY THROUGH THE FORECAST AREA WEDNESDAY NIGHT. THUNDERSTORMS ARE EXPECTED TO CONTINUE TO DEVELOP ALONG THE FRONT DURING THE EVENING WITH MORE THUNDERSTORMS MOVING THROUGH THE AREA DURING THE NIGHT AS THE UPPER LEVEL WAVE MOVES INTO THE AREA. THE BEST MUCAPE DURING THIS PERIOD WILL BE DURING THE EVENING HOURS...THEN DIMINISHING LATE WEDNESDAY NIGHT...SO EXPECT ANY SEVERE WEATHER TO BE MAINLY DURING THE EVENING HOURS. THE FRONT LINGERS JUST TO THE EAST THURSDAY MORNING AND PRECIPITATION COULD LINGER INTO THE MORNING HOURS IN THE EAST...BUT THEN AS ANOTHER UPPER LEVEL WAVE MOVES INTO THE AREA DURING THE AFTERNOON THUNDERSTORMS COULD DEVELOP ALONG THE FRONT AND SOME OF THEM COULD BE IN THE EASTERN PART OF THE FORECAST AREA. MOST OF THE AREA WILL BE DRY MOST OF THE DAY. THERE IS GENERALLY NORTHWEST FLOW ACROSS THE AREA DURING THE PERIOD...WITH SEVERAL UPPER LEVEL WAVES THAT MOVE THROUGH. EACH OF THE WAVES BRING THE CHANCE FOR SOME THUNDERSTORMS TO THE AREA. IT CERTAINLY WILL NOT BE RAINING ALL OF THE TIME OVER ALL OF THE AREA...BUT THERE IS A CHANCE. MOST OF THESE ARE PRETTY SMALL CHANCES SINCE THE MODELS HAVE SLIGHT DIFFERENCE IN THE TIMING OF EACH OF THE WAVES. THE BEST CHANCES FOR THUNDERSTORMS WILL BE SATURDAY NIGHT AND SUNDAY NIGHT WHEN THE STRONGEST OF THE UPPER LEVEL WAVES WILL BE MOVING THROUGH. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING) ISSUED AT 640 PM CDT TUE JUN 17 2014 PREVAILING VFR CONDITIONS ARE EXPECTED FOR THE NEXT 24 HOURS AHEAD OF A COLD FRONT EXPECTED TO REACH SOUTH CENTRAL NEBRASKA BRINGING A CHANCE FOR THUNDERSTORMS JUST BEYOND THE CURRENT SCOPE OF THE TAF. IN THE MEANTIME...EXPECT SOME PASSING HIGH CLOUDS OVERNIGHT WITH A 50-60KT LOW LEVEL JET POINTED TOWARDS SOUTHEASTERN NEBRASKA. AS A RESULT...COULD SEE SOME WIND SHEAR AT BOTH TERMINALS AFT 18/09Z...WITH THIS SHEAR DIMINISHING DURING THE MORNING HOURS. SURFACE WINDS WILL BE GENERALLY OUT OF THE SOUTH OR SOUTH SOUTHWEST THROUGH THE PERIOD AT 15 KTS OR LESS. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ SHORT TERM...BRYANT LONG TERM...JCB AVIATION...ROSSI
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
414 PM CDT MON JUN 16 2014 .SHORT TERM...(TONIGHT THROUGH THURSDAY) ISSUED AT 411 PM CDT MON JUN 16 2014 ELEMENTS NECESSARY FOR SVR STORM DEVELOPMENT COMING TOGETHER LATE THIS AFTN AND EVENING. AN OPEN GULF THE LAST 24HR HAS ALLOWED STRONG MOISTURE TRANSPORT INTO THE CNTRL PLAINS. MESO ANALYSIS INDICATING SFC DEW PTS IN THE LOW 70S HAVE PUSHED IN THE CWA ALONG WITH PWS VALUES APPROACHING 1.75". WITH STRONG BNDRY LYR THETA-E ADV UNDERWAY...INSTABILITY PARAMETERS HAVE INCREASED SIGNIFICANTLY WITH SBCAPES PUSHING 5500J/KG...LI -14. ALONG WITH FAVORABLE EFF-SRH IN PLACE...TORNADIC SUPERCELL DEVELOPMENT IS QUITE LIKELY...ESPECIALLY OVER THE NRN CWA WHERE BEST 0-1KM SRH...LOW LFC/LCL WILL BE FOCUSED. TWD LATE EVENING HRRR IS SHOWING STORMS EVOLVING INTO AN MCS AS IT MOVES INTO NW IA. TUES AND WED HEFTY MOISTURE WILL STILL BE IN PLACE TO PHASE WITH MUCH WARMER AIRMASS ADVECTING IN ALLOWING FOR QUITE MUGGY CONDITIONS. NAM AND GFS STILL PROG HEAT INDICES APPROACHING/AROUND 100 DEG BOTH DAYS. WED NIGHT...NEXT ROUND OF TSTM ACTIVITY EXPECTED TO FORM ON NOSE OF LLVL JET/BNDRY LYR THETA-E CONVG. HVY RA LOOKS PROBABLE GIVEN FAVORABLE PCPN EFFICIENCY/KI VALUES 40/PWS CLOSE TO 2". ACTIVITY THEN PROGGED TO GRADUALLY TAPER OFF ON THURSDAY. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ SHORT TERM...DEE
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
648 AM CDT MON JUN 16 2014 .SHORT TERM...(TODAY THROUGH WEDNESDAY) ISSUED AT 330 AM CDT MON JUN 16 2014 ELEVATED CONVECTION IS TRYING TO INITIATE ACROSS CENTRAL NEBRASKA ON THE NOSE OF A 45-50 KNOT LOW LEVEL JET...WHICH IS ALSO COINCIDENT WITH THE INCREASE OF GULF MOISTURE AS THETAE ADVECTION CONTINUES FROM THE SOUTHERN PLAINS. THIS CLUSTER OF SHOWERS IS EXPECTED TO CONTINUE TO STRENGTHEN THROUGH DAYBREAK AND BECOME A CLUSTER OF POTENTIALLY STRONG THUNDERSTORMS THAT COULD HAVE SOME LARGE HAIL YET THIS MORNING. RAP CONTINUES TO MOVE THIS INTO PRIMARILY NORTHEAST NEBRASKA THROUGH THE MORNING...BUT AS DAYTIME HEATING BEGINS AFTER SUNRISE...COULD SEE A SOUTHWARD EXTENSION THROUGH THE REMAINDER OF THE FORECAST AREA THAT WILL CONTINUE TO SLOWLY PUSH EAST THROUGH THE MORNING. WILL HAVE UP TO 50 PERCENT CHANCE OF STORMS IN NORTHEAST NEBRASKA THIS MORNING...BUT JUST 20 TO 30 PERCENT SOUTHWARD ACROSS REMAINDER OF FORECAST AREA. THERE IS A BROAD AREA OF LOW PRESSURE ACROSS THE FRONT RANGE EARLY THIS MORNING...WITH A PSEUDO WARM WARM FRONT EXTENDING EAST SOUTHEAST FROM THE LOW...WHICH IS ALSO PRIMARILY THE LEADING EDGE OF UPPER 60S/NEAR 70 DEWPOINTS THAT WILL ALSO OVERSPREAD THE REGION TODAY. H85 DEWPOINT MOISTURE ALSO SUBSTANTIALLY INCREASES THROUGH THE DAY...RESULTING IN HIGH INSTABILITY DEVELOPING... COMBINED WITH DEEP BULK SHEAR OF 40 TO 50 KNOTS. AFTER THE MORNING ACTIVITY...THERE MAY BE AN HOUR OR TWO BREAK...WITH ADDITIONAL THUNDERSTORMS DEVELOPING BY MID/LATE AFTERNOON THAT WILL CONTINUE THROUGH THE EVENING. BY THEN...THE REAL WARM FRONT COULD BE MOVING THROUGH THE NORTH PART OF THE FORECAST AREA. STEEP MID LEVEL LAPSE RATES ALSO ACROSS THE REGION ALONG WITH VERY HIGH INSTABILITY WITH CAPE VALUES FROM 2000-4000 J/KG SHOULD ALLOW FOR VERY LARGE HAIL TO DEVELOP WITHIN SUPERCELLS THIS AFTERNOON/EVENING. BELIEVE THE REAL TORNADO THREAT WILL PROBABLY BE IN OUR FAR NORTHERN FORECAST AREA CLOSER TO THE WARM FRONT SAY BETWEEN KOMA AND SUX...WITH LARGE HAIL AND DAMAGING WINDS POSSIBLE ACROSS THE REMAINDER OF THE AREA SOUTHWARD FROM THE FRONT. WHATEVER DEVELOPS WOULD PROBABLY MOSTLY BE OVER BY 06Z...WITH FOCUS SHIFTING EAST OF THE FORECAST AREA BY THEN. SPC DOES HAVE THE REGION IN A SLIGHT RISK FOR SEVERE STORMS AND HAVE NO DOUBT WE`LL HAVE WATCHES ISSUED AT SOME POINT. COULD SEE A WATCH YET THIS MORNING FOR HAIL THAT MIGHT CLIP PORTIONS OF NORTHEAST NEBRASKA...THEN ADDITIONAL SEVERE WEATHER THREAT THIS AFTERNOON AND EVENING. THEREAFTER...WE`RE LOOKING AT A COUPLE OF HOT AND HUMID DAYS FOR TUESDAY AND WEDNESDAY. HIGHS SHOULD EASILY REACH THE LOWER/MID 90S TUESDAY...AND WHEN COMBINED WITH DEWPOINTS IN THE UPPER 60S/LOWER 70S...SHOULD SEE HEAT INDEX VALUES IN THE UPPER 90S TO LOWER 100S. AND WHILE THIS IS BELOW HEAT ADVISORY CRITERIA...IT WILL BE THE FIRST REALLY HOT/HUMID DAY WE`VE EXPERIENCED THIS YEAR. BREEZY SOUTHWESTERLY WINDS WILL WILL NOT OFFER MUCH COOLING EITHER. THE SREF AND GFS DO HINT AT ISOLATED STORM DEVELOPMENT TUESDAY EVENING... BUT BELIEVE WE WILL BE EFFECTIVELY CAPPED WITH H70 TEMPS OF +11 TO +12 ACROSS THE AREA...THUS WILL LEAVE IT DRY TUESDAY NIGHT WITH MUGGY CONDITIONS AND LOWS ONLY IN THE LOWER/MID 70S. WEDNESDAY IS ANOTHER HOT DAY WITH HIGHS IN THE LOWER 90S AND JUST AS HUMID AS TUESDAY...WITH HEAT INDEX VALUES AGAIN IN THE UPPER 90S. THERE IS A FRONTAL BOUNDARY AND ASSOCIATED UPPER WAVE APPROACHING THE AREA FROM THE WEST...BUT BELIEVE CONVECTION WILL HOLD OFF IN OUR AREA UNTIL WEDNESDAY NIGHT AND FEEL THAT SREF MAY BE TOO QUICK ON DEVELOPMENT. .LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY) ISSUED AT 330 AM CDT MON JUN 16 2014 AFOREMENTIONED WAVE MOVES INTO THE REGION WEDNESDAY NIGHT THEN ACROSS THE AREA ON THURSDAY. THIS SHOULD BRING IN ANOTHER GOOD CHANCE OF STORMS WITH 40-60 PERCENT CHANCE...WHICH PUSHES THROUGH THE AREA ON THURSDAY AND EAST/OUT OF THE REGION THURSDAY NIGHT. ANOTHER WAVE MATERIALIZES ON THE GFS BY FRIDAY AND MOVES THROUGH THE AREA FRIDAY NIGHT ALTHOUGH THE ECMWF IS GENERALLY DRY...SO CONFIDENCE THAT FAR OUT IS TYPICALLY LOW. WILL OPT FOR A DRY FORECAST SATURDAY...BUT MODELS DO HINT AT ANOTHER WEAK FRONT IN THE AREA. && .AVIATION...(12Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 642 AM CDT MON JUN 16 2014 AVIATION CONCERNS TODAY WILL BE RETURN OF DEEP MOISTURE... FOG...STRATUS AND CONVECTION ALONG WITH STRENGTHENING LOW LEVEL WINDS. AN AREA OF SHOWERS AND ISOLATED THUNDERSTORMS DEVELOPED OVER CENTRAL NEBRASKA AND THESE WILL CONTINUE TO SHIFT EAST THIS MORNING. KOFK SHOULD SEE THE BEST COVERAGE AND WILL INCLUDE A TEMPO GROUP THERE SHOULD BE MORE ISOLATED IN NATURE AT KOMA AND KLNK WITH SOME MVFR/IFR/PATCHY LIFT CIGS AND VSBYS. THERE MAY BE A BREAK IN THE ACTIVITY LATE THIS MORNING WITH COVERAGE INCREASING IN THE AFTERNOON AND EVENING AGAIN. INSTABILITY GREATLY INCREASES THIS AFTERNOON AND WILL NEED TO WATCH STRENGTH OF STORMS FOR HAIL AND HIGH WINDS. IF WARM MID LEVEL TEMPERATURES MOVE IN...THESE MAY LIMIT TSTORM COVERAGE AT KLNK AND KOMA THIS AFTERNOON. LIGHT SOUTHEAST WINDS EARLY...WILL QUICKLY STRENGTHEN TO 15 TO 25 KTS WITH GUSTS TO 30KTS THROUGH THE AFTERNOON. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ SHORT TERM...DEWALD LONG TERM...DEWALD AVIATION...ZAPOTOCNY
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
331 AM CDT MON JUN 16 2014 .SHORT TERM...(TODAY THROUGH WEDNESDAY) ISSUED AT 330 AM CDT MON JUN 16 2014 ELEVATED CONVECTION IS TRYING TO INITIATE ACROSS CENTRAL NEBRASKA ON THE NOSE OF A 45-50 KNOT LOW LEVEL JET...WHICH IS ALSO COINCIDENT WITH THE INCREASE OF GULF MOISTURE AS THETAE ADVECTION CONTINUES FROM THE SOUTHERN PLAINS. THIS CLUSTER OF SHOWERS IS EXPECTED TO CONTINUE TO STRENGTHEN THROUGH DAYBREAK AND BECOME A CLUSTER OF POTENTIALLY STRONG THUNDERSTORMS THAT COULD HAVE SOME LARGE HAIL YET THIS MORNING. RAP CONTINUES TO MOVE THIS INTO PRIMARILY NORTHEAST NEBRASKA THROUGH THE MORNING...BUT AS DAYTIME HEATING BEGINS AFTER SUNRISE...COULD SEE A SOUTHWARD EXTENSION THROUGH THE REMAINDER OF THE FORECAST AREA THAT WILL CONTINUE TO SLOWLY PUSH EAST THROUGH THE MORNING. WILL HAVE UP TO 50 PERCENT CHANCE OF STORMS IN NORTHEAST NEBRASKA THIS MORNING...BUT JUST 20 TO 30 PERCENT SOUTHWARD ACROSS REMAINDER OF FORECAST AREA. THERE IS A BROAD AREA OF LOW PRESSURE ACROSS THE FRONT RANGE EARLY THIS MORNING...WITH A PSEUDO WARM WARM FRONT EXTENDING EAST SOUTHEAST FROM THE LOW...WHICH IS ALSO PRIMARILY THE LEADING EDGE OF UPPER 60S/NEAR 70 DEWPOINTS THAT WILL ALSO OVERSPREAD THE REGION TODAY. H85 DEWPOINT MOISTURE ALSO SUBSTANTIALLY INCREASES THROUGH THE DAY...RESULTING IN HIGH INSTABILITY DEVELOPING... COMBINED WITH DEEP BULK SHEAR OF 40 TO 50 KNOTS. AFTER THE MORNING ACTIVITY...THERE MAY BE AN HOUR OR TWO BREAK...WITH ADDITIONAL THUNDERSTORMS DEVELOPING BY MID/LATE AFTERNOON THAT WILL CONTINUE THROUGH THE EVENING. BY THEN...THE REAL WARM FRONT COULD BE MOVING THROUGH THE NORTH PART OF THE FORECAST AREA. STEEP MID LEVEL LAPSE RATES ALSO ACROSS THE REGION ALONG WITH VERY HIGH INSTABILITY WITH CAPE VALUES FROM 2000-4000 J/KG SHOULD ALLOW FOR VERY LARGE HAIL TO DEVELOP WITHIN SUPERCELLS THIS AFTERNOON/EVENING. BELIEVE THE REAL TORNADO THREAT WILL PROBABLY BE IN OUR FAR NORTHERN FORECAST AREA CLOSER TO THE WARM FRONT SAY BETWEEN KOMA AND SUX...WITH LARGE HAIL AND DAMAGING WINDS POSSIBLE ACROSS THE REMAINDER OF THE AREA SOUTHWARD FROM THE FRONT. WHATEVER DEVELOPS WOULD PROBABLY MOSTLY BE OVER BY 06Z...WITH FOCUS SHIFTING EAST OF THE FORECAST AREA BY THEN. SPC DOES HAVE THE REGION IN A SLIGHT RISK FOR SEVERE STORMS AND HAVE NO DOUBT WE`LL HAVE WATCHES ISSUED AT SOME POINT. COULD SEE A WATCH YET THIS MORNING FOR HAIL THAT MIGHT CLIP PORTIONS OF NORTHEAST NEBRASKA...THEN ADDITIONAL SEVERE WEATHER THREAT THIS AFTERNOON AND EVENING. THEREAFTER...WE`RE LOOKING AT A COUPLE OF HOT AND HUMID DAYS FOR TUESDAY AND WEDNESDAY. HIGHS SHOULD EASILY REACH THE LOWER/MID 90S TUESDAY...AND WHEN COMBINED WITH DEWPOINTS IN THE UPPER 60S/LOWER 70S...SHOULD SEE HEAT INDEX VALUES IN THE UPPER 90S TO LOWER 100S. AND WHILE THIS IS BELOW HEAT ADVISORY CRITERIA...IT WILL BE THE FIRST REALLY HOT/HUMID DAY WE`VE EXPERIENCED THIS YEAR. BREEZY SOUTHWESTERLY WINDS WILL WILL NOT OFFER MUCH COOLING EITHER. THE SREF AND GFS DO HINT AT ISOLATED STORM DEVELOPMENT TUESDAY EVENING... BUT BELIEVE WE WILL BE EFFECTIVELY CAPPED WITH H70 TEMPS OF +11 TO +12 ACROSS THE AREA...THUS WILL LEAVE IT DRY TUESDAY NIGHT WITH MUGGY CONDITIONS AND LOWS ONLY IN THE LOWER/MID 70S. WEDNESDAY IS ANOTHER HOT DAY WITH HIGHS IN THE LOWER 90S AND JUST AS HUMID AS TUESDAY...WITH HEAT INDEX VALUES AGAIN IN THE UPPER 90S. THERE IS A FRONTAL BOUNDARY AND ASSOCIATED UPPER WAVE APPROACHING THE AREA FROM THE WEST...BUT BELIEVE CONVECTION WILL HOLD OFF IN OUR AREA UNTIL WEDNESDAY NIGHT AND FEEL THAT SREF MAY BE TOO QUICK ON DEVELOPMENT. .LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY) ISSUED AT 330 AM CDT MON JUN 16 2014 AFOREMENTIONED WAVE MOVES INTO THE REGION WEDNESDAY NIGHT THEN ACROSS THE AREA ON THURSDAY. THIS SHOULD BRING IN ANOTHER GOOD CHANCE OF STORMS WITH 40-60 PERCENT CHANCE...WHICH PUSHES THROUGH THE AREA ON THURSDAY AND EAST/OUT OF THE REGION THURSDAY NIGHT. ANOTHER WAVE MATERIALIZES ON THE GFS BY FRIDAY AND MOVES THROUGH THE AREA FRIDAY NIGHT ALTHOUGH THE ECMWF IS GENERALLY DRY...SO CONFIDENCE THAT FAR OUT IS TYPICALLY LOW. WILL OPT FOR A DRY FORECAST SATURDAY...BUT MODELS DO HINT AT ANOTHER WEAK FRONT IN THE AREA. && .AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1120 PM CDT SUN JUN 15 2014 MOISTURE AND INSTABILITY STILL ON TAP TO RETURN TO ERN NEBRASKA LATE TONIGHT AS LOW LEVEL SRLY WINDS INCREASE. THIS IN TURN COULD LEAD TO ISOLATED TO SCATTERED THUNDERSTORMS ACROSS THE REGION MONDAY MORNING. MENTION WAS MAINTAINED AT KLNK AND KOFK WHERE CHANCES APPEARED SOMEWHAT HIGHER THAN KOMA. IN ADDITION AS LOW LEVEL MOISTURE RETURNS...MVFR CIGS COULD DEVELOP/ADVECT OVER THE AREA BUT CONFIDENCE IN COVERAGE OR EVEN AT WHAT FLIGHT LEVEL EVENTUAL CIGS END UP IS LOW. ADDITIONAL TSTM DEVELOPMENT EXPECTED LATER IN THE AFTERNOON/EARLY EVENING AS CONDITIONS BECOME EVEN MORE UNSTABLE AND A WARM FRONT SETS UP OVER THE NERN NEBR/WRN IA VICINITY. EXPECT CONCENTRATION PROBABLY IN THAT AREA AND LOCATIONS JUST NORTH WITH KOFK PROBABLY MORE UNDER THE GUN THAN KOMA AND EVEN MORE SO THAN KLNK. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ SHORT TERM...DEWALD LONG TERM...DEWALD AVIATION...CHERMOK
AREA FORECAST DISCUSSION
NWS BISMARCK ND
559 PM CDT MON JUN 16 2014 .UPDATE... ISSUED AT 558 PM CDT MON JUN 16 2014 FOLLOWING THE 20-21 UTC RAP/HRRR RUNS...SUPPORTED BY STABLE 18 UTC NAM/GFS BUFR SOUNDINGS AND THE LACK OF A CUMULUS FIELD LATE THIS AFTERNOON...REMOVED POPS GENERALLY ALONG AND EAST OF NORTH DAKOTA HIGHWAY 3. ACROSS THE SOUTHWEST ISOLATED CELLS HAVE DEVELOPED. HOWEVER...RATHER WEAK MID LEVEL LAPSE RATES APPEAR TO BE LIMITING INTENSITY. ML CAPE OF 1500-2000 J/KG WITH DEEP LAYER SHEAR OF 40 KTS IS IN PLACE ACROSS THE SOUTHWEST. WILL CONTINUE TO MONITOR FOR SEVERE CONVECTION...HOWEVER...THE COVERAGE OF ANY SEVERE THREAT WILL BE ISOLATED. FINALLY...GIVEN UPSLOPE EASTERLY FLOW...DID ADD A MENTION OF PATCHY FOG TO THE SOUTHWEST TONIGHT. && .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 250 PM CDT MON JUN 16 2014 MAIN FORECAST ISSUE IN THE SHORT TERM PERIOD WILL BE THUNDERSTORM CHANCE...GO FIGURE. SURFACE LOW PRESSURE SITUATED OVER SOUTHEAST MONTANA WITH AN INVERTED TROUGH INTO WEST CENTRAL SOUTH DAKOTA. ORGANIZED CONVECTION ACROSS SOUTH DAKOTA AND INTO MINNESOTA ALONG AN OLD BOUNDARY. LATEST SHORT RANGE GUIDANCE SUGGESTS THAT DESTABILIZATION SHOULD CONTINUE TO OCCUR OVER SOUTHWEST NORTH DAKOTA LATE THIS AFTERNOON ALONG A DEVELOPING BOUNDARY INTO CENTRAL NORTH DAKOTA. THE LAST FEW RUNS OF THE HRRR INDICATE CONVECTION DEVELOPING IN WESTERN NORTH DAKOTA LATE THIS AFTERNOON AND TRACKING EAST INTO CENTRAL NORTH DAKOTA. BUMPED UP POPS TO CHANCE CATEGORY IN THE WEST THIS AFTERNOON...AND WILL MENTION THE POSSIBILITY OF SEVERE STORMS. LATEST ITERATIONS OF THE HRRR AND RAP CONTINUE TO DIMINISH CONVECTION AS IT MOVES INTO CENTRAL NORTH DAKOTA THIS EVENING. ON TUESDAY...THE UPPER LOW OVER THE WESTERN U.S. MOVES INTO THE NORTHERN ROCKIES. UPPER LEVEL ASCENT WILL BE FOCUSED OVER EASTER MONTANA...BUT AS WE MOVE THROUGH THE DAY...THE HEAVY PRECIPITATION POTENTIAL WILL MOVE CLOSE TO THE NORTH DAKOTA BORDER. CONSIDERED A FLASH FLOOD WATCH...BUT WITH THE INCREASED POTENTIAL HOLDING OFF UNTIL AT LEAST TUESDAY AFTERNOON BUT MORE LIKE TUESDAY EVENING THROUGH WEDNESDAY MORNING...WILL LET THE NEXT SHIFT TAKE ANOTHER LOOK. PREVIOUS SHIFT HAD ADDED THE MENTION OF HEAVY RAIN TO THE FAR WEST AND WILL CONTINUE THIS AGAIN. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 250 PM CDT MON JUN 16 2014 THE MEDIUM RANGE MODELS CONTINUE TO PROG AN UNSETTLED WEATHER PATTERN OVER WESTERN AND CENTRAL NORTH DAKOTA THROUGH MUCH OF THE WORK WEEK. THE MEDIUM RANGE MODELS ARE BEGINNING TO COME INTO BETTER AGREEMENT REGARDING MOVING THE UPPER LOW EASTWARD AND MOVING A RIDGE INTO THE DAKOTAS BY THE WEEKEND. THE MODELS ARE CONSISTENT IN THE NEAR TERM PLACING THE LARGE UPPER LEVEL LOW OVER THE NORTHERN US ROCKIES STATES TUESDAY NIGHT...WITH THE LOW LIFTING NORTHEAST INTO SOUTHERN SASKATCHEWAN THURSDAY...AND MOVING IT EAST ACROSS NORTH DAKOTA THURSDAY NIGHT AND FRIDAY. TUESDAY NIGHT THROUGH THURSDAY: ON TUESDAY NIGHT A SURFACE LOW IS FORECAST TO EXTEND FROM A LOW OVER KANSAS NORTHWESTWARD ACROSS WESTERN SOUTH DAKOTA INTO EASTERN MONTANA. THIS SURFACE BOUNDARY IS FORECAST TO LIFT NORTHEASTWARD INTO NORTH DAKOTA WEDNESDAY MORNING...AND INTO SOUTH CENTRAL CANADA WEDNESDAY NIGHT/THURSDAY. DURING THIS TIME THE INGREDIENTS FOR SEVERE THUNDERSTORMS WILL BE IN PLACE. A LOW LEVEL JET BRINGING PLENTY OF MOISTURE AND ADDITIONAL FORCING FOR THUNDERSTORM DEVELOPMENT...COMBINED WITH THE SURFACE BOUNDARY...AND THE STRONG UPPER LEVEL JET ASSOCIATED WITH THE UPPER LOW WILL BRING PLENTY OF CAPE AND SHEAR FOR SUSTAINING THUNDERSTORMS. AT THIS TIME IT APPEARS THE BEST CHANCE FOR SEVERE STORMS TUESDAY NIGHT WILL BE ALONG AND SOUTH OF HIGHWAY 2. BY WEDNESDAY THE THREAT IS MAINLY ALONG AND EAST OF HIGHWAY 85. BY THURSDAY AFTERNOON AND NIGHT...THE UPPER LEVEL LOW SHOULD BE NEAR THE ND/MT/SASKATCHEWAN BORDER. THIS IS FAVORABLE FOR AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS. ON THURSDAY NIGHT AND FRIDAY THE UPPER LOW MOVES EAST ACROSS THE STATE...WITH CONTINUED SCATTERED SHOWERS AND THUNDERSTORMS. TUESDAY NIGHT THROUGH FRIDAY NIGHT: BY THE END OF THE WEEK THERE WILL HAVE BEEN A GOOD CHANCE OF WIDESPREAD SHOWERS AND THUNDERSTORMS - WITH THE ADDITIONAL THREAT OF HEAVY RAINS. WILL CONTINUE TO HIGHLIGHT THE HEAVY RAIN THREAT ACROSS THE FORECAST AREA IN THE HAZARDOUS WEATHER OUTLOOK. SATURDAY THROUGH MONDAY...THE MODELS ARE IN BETTER AGREEMENT AND BUILD A WEAK SHORTWAVE RIDGE OVER MONTANA/DAKOTAS. A FEW WEAK UPPER LEVEL IMPULSES MOVING THROUGH THE WEAK RIDGE WILL RESULT IN ONLY SMALL CHANCES OF THUNDERSTORMS IN THE FORECAST FOR THE WEEKEND. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING) ISSUED AT 558 PM CDT MON JUN 16 2014 VFR CONDITIONS WILL BEGIN THE 00 UTC TAF CYCLE WITH ISOLATED TO SCATTED THUNDERSTORMS ACROSS WESTERN NORTH DAKOTA. KDIK IS THE MOST LIKELY TERMINAL TO BE IMPACTED. WITH EASTERLY UPSLOPE FLOW TONIGHT...MVFR/IFR FOG AND STRATUS IS EXPECTED TO DEVELOP AT KDIK AND POSSIBLY KISN AND KBIS. KMOT AND KJMS LOOK TO REMAIN ON THE FRINGE OF THIS FOG AND STRATUS DEVELOPMENT. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...AYD SHORT TERM...TWH LONG TERM...JV AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
250 PM CDT MON JUN 16 2014 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 250 PM CDT MON JUN 16 2014 MAIN FORECAST ISSUE IN THE SHORT TERM PERIOD WILL BE THUNDERSTORM CHANCE...GO FIGURE. SURFACE LOW PRESSURE SITUATED OVER SOUTHEAST MONTANA WITH AN INVERTED TROUGH INTO WEST CENTRAL SOUTH DAKOTA. ORGANIZED CONVECTION ACROSS SOUTH DAKOTA AND INTO MINNESOTA ALONG AN OLD BOUNDARY. LATEST SHORT RANGE GUIDANCE SUGGESTS THAT DESTABILIZATION SHOULD CONTINUE TO OCCUR OVER SOUTHWEST NORTH DAKOTA LATE THIS AFTERNOON ALONG A DEVELOPING BOUNDARY INTO CENTRAL NORTH DAKOTA. THE LAST FEW RUNS OF THE HRRR INDICATE CONVECTION DEVELOPING IN WESTERN NORTH DAKOTA LATE THIS AFTERNOON AND TRACKING EAST INTO CENTRAL NORTH DAKOTA. BUMPED UP POPS TO CHANCE CATEGORY IN THE WEST THIS AFTERNOON...AND WILL MENTION THE POSSIBILITY OF SEVERE STORMS. LATEST ITERATIONS OF THE HRRR AND RAP CONTINUE TO DIMINISH CONVECTION AS IT MOVES INTO CENTRAL NORTH DAKOTA THIS EVENING. ON TUESDAY...THE UPPER LOW OVER THE WESTERN U.S. MOVES INTO THE NORTHERN ROCKIES. UPPER LEVEL ASCENT WILL BE FOCUSED OVER EASTER MONTANA...BUT AS WE MOVE THROUGH THE DAY...THE HEAVY PRECIPITATION POTENTIAL WILL MOVE CLOSE TO THE NORTH DAKOTA BORDER. CONSIDERED A FLASH FLOOD WATCH...BUT WITH THE INCREASED POTENTIAL HOLDING OFF UNTIL AT LEAST TUESDAY AFTERNOON BUT MORE LIKE TUESDAY EVENING THROUGH WEDNESDAY MORNING...WILL LET THE NEXT SHIFT TAKE ANOTHER LOOK. PREVIOUS SHIFT HAD ADDED THE MENTION OF HEAVY RAIN TO THE FAR WEST AND WILL CONTINUE THIS AGAIN. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 250 PM CDT MON JUN 16 2014 THE MEDIUM RANGE MODELS CONTINUE TO PROG AN UNSETTLED WEATHER PATTERN OVER WESTERN AND CENTRAL NORTH DAKOTA THROUGH MUCH OF THE WORK WEEK. THE MEDIUM RANGE MODELS ARE BEGINNING TO COME INTO BETTER AGREEMENT REGARDING MOVING THE UPPER LOW EASTWARD AND MOVING A RIDGE INTO THE DAKOTAS BY THE WEEKEND. THE MODELS ARE CONSISTENT IN THE NEAR TERM PLACING THE LARGE UPPER LEVEL LOW OVER THE NORTHERN US ROCKIES STATES TUESDAY NIGHT...WITH THE LOW LIFTING NORTHEAST INTO SOUTHERN SASKATCHEWAN THURSDAY...AND MOVING IT EAST ACROSS NORTH DAKOTA THURSDAY NIGHT AND FRIDAY. TUESDAY NIGHT THROUGH THURSDAY: ON TUESDAY NIGHT A SURFACE LOW IS FORECAST TO EXTEND FROM A LOW OVER KANSAS NORTHWESTWARD ACROSS WESTERN SOUTH DAKOTA INTO EASTERN MONTANA. THIS SURFACE BOUNDARY IS FORECAST TO LIFT NORTHEASTWARD INTO NORTH DAKOTA WEDNESDAY MORNING...AND INTO SOUTH CENTRAL CANADA WEDNESDAY NIGHT/THURSDAY. DURING THIS TIME THE INGREDIENTS FOR SEVERE THUNDERSTORMS WILL BE IN PLACE. A LOW LEVEL JET BRINGING PLENTY OF MOISTURE AND ADDITIONAL FORCING FOR THUNDERSTORM DEVELOPMENT...COMBINED WITH THE SURFACE BOUNDARY...AND THE STRONG UPPER LEVEL JET ASSOCIATED WITH THE UPPER LOW WILL BRING PLENTY OF CAPE AND SHEAR FOR SUSTAINING THUNDERSTORMS. AT THIS TIME IT APPEARS THE BEST CHANCE FOR SEVERE STORMS TUESDAY NIGHT WILL BE ALONG AND SOUTH OF HIGHWAY 2. BY WEDNESDAY THE THREAT IS MAINLY ALONG AND EAST OF HIGHWAY 85. BY THURSDAY AFTERNOON AND NIGHT...THE UPPER LEVEL LOW SHOULD BE NEAR THE ND/MT/SASKATCHEWAN BORDER. THIS IS FAVORABLE FOR AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS. ON THURSDAY NIGHT AND FRIDAY THE UPPER LOW MOVES EAST ACROSS THE STATE...WITH CONTINUED SCATTERED SHOWERS AND THUNDERSTORMS. TUESDAY NIGHT THROUGH FRIDAY NIGHT: BY THE END OF THE WEEK THERE WILL HAVE BEEN A GOOD CHANCE OF WIDESPREAD SHOWERS AND THUNDERSTORMS - WITH THE ADDITIONAL THREAT OF HEAVY RAINS. WILL CONTINUE TO HIGHLIGHT THE HEAVY RAIN THREAT ACROSS THE FORECAST AREA IN THE HAZARDOUS WEATHER OUTLOOK. SATURDAY THROUGH MONDAY...THE MODELS ARE IN BETTER AGREEMENT AND BUILD A WEAK SHORTWAVE RIDGE OVER MONTANA/DAKOTAS. A FEW WEAK UPPER LEVEL IMPULSES MOVING THROUGH THE WEAK RIDGE WILL RESULT IN ONLY SMALL CHANCES OF THUNDERSTORMS IN THE FORECAST FOR THE WEEKEND. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 250 PM CDT MON JUN 16 2014 SCATTERED THUNDERSTORMS ARE POSSIBLE LATE THIS AFTERNOON AND THIS EVENING ACROSS WESTERN NORTH DAKOTA. EXCEPT FOR ISOLATED MVFR CEILINGS/VISIBILITIES POSSIBLE IN THUNDERSTORMS...VFR CONDITIONS ARE EXPECTED LATE AFTERNOON AND THIS EVENING. MODELS ARE INCREASING LOW LEVEL MOISTURE WITH MVFR-IFR CEILINGS POSSIBLE BY LATE EVENING AND THROUGH TUESDAY MORNING. THIS IS CERTAINLY POSSIBLE WITH A STEADY EASTERLY FLOW INTO SURFACE LOW PRESSURE OVER SOUTHEAST MONTANA...THUS HAVE BROUGHT IN AN AREA OF MVFR CEILINGS ACROSS ALL TAF SITES...BUT DELAYED THIS UNTIL BASICALLY AFTER 12 UTC TUESDAY. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...TWH LONG TERM...JV AVIATION...TWH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
103 PM CDT MON JUN 16 2014 .UPDATE... ISSUED AT 105 PM CDT MON JUN 16 2014 SURFACE LOW PRESSURE OVER THE MONDAY REGION WITH CONVECTION ACROSS CENTRAL AND EASTERN SOUTH DAKOTA ALONG A STATIONARY FRONT. A FEW STORMS CROSSED THE BORDER EARLIER THIS MORNING...WITH ANOTHER AREA OF CONVECTION CURRENTLY DIMINISHING OVER SOUTHERN EMMONS/MCINTOSH COUNTIES AS STORMS RUN INTO MORE STABLE AIR. WE CONTINUE TO DESTABILIZE OVER SOUTHWEST NORTH DAKOTA WHERE SKIES HAVE CLEARED. LATEST FEW RUNS OF THE RAP AND ESPECIALLY HRRR HAVE INDICATED CONVECTION DEVELOPING OVER SOUTHWEST NORTH DAKOTA AND TRACKING EAST ACROSS THE SOUTHWEST/SOUTH CENTRAL. WITH DECENT BULK SHEAR AND INCREASING INSTABILITY EXPECTED THIS AFTERNOON...HAVE BUMPED UP THE THUNDERSTORM CHANCES IN THE SOUTHWEST LATE THIS AFTERNOON INTO THE CHANCE CATEGORY. MAIN THREAT WILL BE LARGE HAIL AND WINDS. CAN NOT RULE OUT AN ISOLATED TORNADO DUE TO THE INCREASED LOW LEVEL SHEAR NEAR THE SURFACE LOW. OTHERWISE NO SIGNIFICANT CHANGES TO THE GOING FORECAST. UPDATE ISSUED AT 1026 AM CDT MON JUN 16 2014 MAIN CHANGES FOR THIS UPDATE...TEMPERATURES AND PRECIPITATION CHANCES. A LINE OF SHOWERS AND THUNDERSTORMS CONTINUES TO SLOWLY TRACK NORTH AND EAST ALONG A WARM FRONT IN SOUTH DAKOTA. THE WARM FRONT AND ASSOCIATED PRECIPITATION SHOULD CONTINUE TO TRACK NORTH THROUGH THE DAY AND ENTER SOUTHERN NORTH DAKOTA LATE THIS MORNING AND INTO THE EARLY AFTERNOON HOURS. FOR THIS UPDATE...BASED ON LATEST RADAR TRENDS AND SHORT-TERM GUIDANCE...INCREASED PRECIPITATION CHANCES ACROSS THE SOUTH AND WEST THROUGH THE DAY. TEMPERATURES STARTED OUT SLIGHTLY WARMER THAN PREVIOUSLY FORECAST THIS MORNING. EVEN WITH THE CLOUD COVER...STRONG WARM AIR ADVECTION WILL SUPPORT WARMER TEMPERATURES TODAY. THEREFORE...INCREASED MAX TEMPERATURES TODAY...MAINLY ACROSS THE SOUTH AND EAST. UPDATE ISSUED AT 745 AM CDT MON JUN 16 2014 QUICK UPDATED FOR THE ADDITION OF ISOLATED MORNING THUNDERSTORMS OVER THE SOUTHEAST CWA. OTHERWISE NO CHANGES TO THE GOING FORECAST. UPDATE ISSUED AT 636 AM CDT MON JUN 16 2014 UPDATED THE FORECAST TO ADD AREAS OF FOG TO THE NORTHWESTERN ZONES PER THE TIOGA AND STANLEY OBS. THE FOG SHOULD BURN OFF BY MID MORNING. OTHERWISE...THE REMAINING WEATHER ELEMENTS ARE IN GOOD SHAPE. THE UPDATED PRODUCTS HAVE BEEN SENT. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 358 AM CDT MON JUN 16 2014 FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD WILL BE CHANCES FOR THUNDERSTORMS TODAY AND TONIGHT...SOME STRONG TO SEVERE ACROSS MY SOUTH CENTRAL AND SOUTHEAST IN THE AFTERNOON/EVENING. CURRENTLY...S/WV MID LEVEL RIDGE AXIS MOVING INTO THE WESTERN DAKOTAS WITH A WEAK SFC HIGH PRESSURE RIDGE OVER THE LOCAL AREA RESULTING IN A MOSTLY CLEAR SKY AT THE MOMENT. S/WV TROUGH OVER NORTHERN WYOMING WITH A DEVELOPING SURFACE LOW ACROSS SOUTHEASTERN MONTANA/EASTERN WYOMING. OFF TO OUR NORTH...MID LEVEL LOW PRESSURE CONTINUES TO SPIN ACROSS SOUTH CENTRAL CANADA. IT APPEARS THE SCT-BKN MVFR CIGS ASSOCIATED WITH THE MID LEVEL LOW TO OUR NORTH WILL REMAIN NORTH OF THE INTERNATIONAL BORDER WITH A WESTERLY WIND COMPONENT HINDERING THE SOUTHWARD ADVANCEMENT OF THE LOW CLOUDS. WILL SEE INCREASING MID TO UPPER LEVEL CLOUDS SOUTHWEST TO NORTHEAST THIS MORNING AS THE MID LEVEL S/WV OVER NORTHERN WYOMING CONTINUES NORTHEAST. THIS FEATURE...COUPLED WITH A SECOND EMBEDDED WAVE LIFTING NORTHEAST ACROSS CENTRAL SOUTH DAKOTA...WILL RESULT IN CHANCES FOR SHOWERS/THUNDERSTORMS INCREASING 12Z-18Z WEST AND ACROSS THE SOUTH. INSTABILITY PARAMETERS INCREASE WITH DAYTIME HEATING AIDING IN THE EXPANSION OF COVERAGE OF STORMS ACROSS THE AREA IN THE AFTERNOON...ESPECIALLY SOUTH CENTRAL AND SOUTHEAST WHERE MODELS PORTRAY THE HIGHER INSTABILITY OF AROUND 1K MUCAPE. 0-6KM WIND SHEAR OF 40-50KTS IN THIS REGION AS WELL...WILL SUPPORT UPDRAFT/DOWNDRAFT DISPLACEMENT PROMOTING STORM LONGEVITY FOR A CHANCE AT A FEW STRONGER STORMS. MAIN SEVERE WEATHER THREATS SOUTH CENTRAL AND SOUTHEAST WILL BE LARGE HAIL AND DAMAGING WINDS WITH ANY ORGANIZED CONVECTION AS INDICATED BY THE SPC DAY ONE OUTLOOK. HOWEVER...A QUASI-STATIONARY WARM FRONT PROGGED TO BE DRAPED WEST TO EAST ACROSS NORTH CENTRAL INTO NORTHEASTERN SOUTH DAKOTA DURING THE AFTERNOON...WILL RESULT IN AN INCREASE IN LOW LEVEL WIND SHEAR NEAR THE ND/SD BORDER OF MY SOUTHEAST (SOUTHERN JAMES RIVER VALLEY OF ND). WILL WANT TO KEEP A CLOSER WATCH ON SOME OF THE MORE ROBUST STORMS HERE FOR ENHANCED MESOS AND POSSIBLE WEAK TORNADOES GIVEN THE POTENTIAL FOR THIS ENHANCED LOW LEVEL WIND SHEAR NEAR THE WARM FRONT. NEXT ROUND OF THUNDERSTORMS WILL BE OVER THE WEST OVERNIGHT AS LEAD S/WV IMPULSES...ORIGINATING FROM A LARGE CLOSED UPPER LOW POSITIONED OVER THE INTERMOUNTAIN WEST...EJECT NORTHEAST ACROSS WYOMING AND INTO THE NORTHERN HIGH PLAINS. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 358 AM CDT MON JUN 16 2014 THE MEDIUM RANGE MODELS CONTINUE TO PROG AN UNSETTLED WEATHER PATTERN OVER WESTERN AND CENTRAL NORTH DAKOTA THROUGH MUCH OF THE EXTENDED. THE ECMWF PROGS A DRYING TREND DEVELOPING BY LATE FRIDAY AND CONTINUING THROUGH SUNDAY. HOWEVER...THE LATEST GEM/GFS HAVE DIFFERENT IDEAS. ON TUESDAY...AN UPPER LEVEL LOW IS PROGGED TO ENTER WESTERN MONTANA. THIS FEATURE SHOULD GENERATE LIKELY POPS ACROSS WESTERN NORTH DAKOTA GIVEN THE INCREASING UPPER LEVEL DYNAMICS AND MOISTURE/INSTABILITY. SPC ALSO PAINTED AREAS ALONG AND SOUTH OF I-94 IN A SLIGHT RISK FOR SEVERE WEATHER TUESDAY AFTERNOON/EVENING. THIS IS COINCIDENT WITH MUCAPE VALUES BETWEEN 1000-1500 J/KG AND 0-6 BULK SHEAR MAGNITUDES AROUND 40 KNOTS. THE FLY IN THE OINTMENT IS THE ABSENCE OF A SURFACE BOUNDARY. FURTHERMORE...HEAVY RAINFALL COULD POSSIBLY DEVELOP WEST TUESDAY NIGHT/EARLY WEDNESDAY MORNING. WILL HIGHLIGHT THESE THREATS IN THE HWO. WEDNESDAY STILL LOOKS TO BE INTERESTING AS THE UPPER LOW LIFTS INTO SOUTHWESTERN SASKATCHEWAN. THE 00Z ECMWF/GEM/GFS PROG THE UPPER LOW`S SURFACE FRONT TO ENTER CENTRAL NORTH DAKOTA BY LATE WEDNESDAY AFTERNOON/EVENING. THE SURFACE BOUNDARY IS PROGGED TO COINCIDE WITH MUCAPE BETWEEN 1500-2000 J/KG ALONG AND EAST OF HIGHWAY 83 AND 0-6 KM BULK SHEAR AROUND 30 KNOTS. THERE`S QUITE A BIT OF UNCERTAINTY WITH REGARDS TO SEVERE WEATHER PARAMETERS ON DAY 3...BUT IF MODELS CONTINUE TO KEEP WITH THE LATEST DETERMINISTIC SOLUTIONS WITH REGARDS TO THE EVOLUTION OF THE UPPER LOW...SEVERE WEATHER COULD BE A POSSIBILITY OVER CENTRAL NORTH DAKOTA WEDNESDAY AFTERNOON/EVENING. THIS IS ALSO CONSISTENT WITH SPC`S DAY 3 OUTLOOK AND WILL THEREFORE HIGHLIGHT THIS POSSIBILITY IN THE HWO AS WELL. THE MEDIUM RANGE MODELS ARE CONSISTENT ROTATING THE UPPER LOW INTO NORTH DAKOTA THURSDAY/THURSDAY NIGHT. THIS WILL LEAD TO CONTINUING THUNDERSTORM CHANCES THURSDAY. THE MEDIUM RANGE MODELS DIVERGE QUITE A BIT WITH THE TRACK OF THE UPPER LOW OVER THE NORTHERN PLAINS FRIDAY AND BEYOND. THE ECMWF IS MORE PROGRESSIVE WITH THE LOW AND BUILDS AN UPPER RIDGE OVER THE STATE FRIDAY THROUGH THE WEEKEND. HOWEVER...THE LATEST GEM/GFS KEEP THE UPPER LOW OVER NORTH DAKOTA FRIDAY AND SATURDAY...WITH RIDGING FINALLY BUILDING IN SUNDAY. GIVEN THE MODEL TO MODEL AND RUN TO RUN INCONSISTENCIES...TOOK THE ALLBLEND APPROACH AND INDICATED SLIGHT CHANCE OF THUNDERSTORMS THROUGH THE WEEKEND. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 105 PM CDT MON JUN 16 2014 MAINLY VFR CIGS/VSBYS FORECAST THROUGH 18Z TUESDAY. A VCSH/VCTS OVER THE AERODROMES LATE THIS AFTERNOONA AND EVENING. AT THIS TIME KJMS LOOKS TO BE THE BEST CANDIDATE FOR SHOWERS AND THUNDERSTORMS MONDAY AFTERNOON/EVENING. HOWEVER WE COULD SEE ADDITIONAL DEVELOPMENT LATE THIS AFTERNOON IN THE FAR SOUTHWEST TO WEST CENTRAL AND TRACKING EAST. LOW MVFR TO IFR CIGS ARE FORECAST TO DEVELOP ACROSS THE SOUTH AROUND TO AFTER 06Z TUESDAY. WILL HOLD OFF ON THIS FOR NOW UNTIL AROUND 12 UTC. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...TWH SHORT TERM...NH LONG TERM...TM AVIATION...TWH
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1234 PM CDT MON JUN 16 2014 .UPDATE... ISSUED AT 1234 PM CDT MON JUN 16 2014 ELEVATED CONVECTION HAS CONTINUED TO SPREAD ACROSS OUR SOUTHERN COUNTIES ON THE LEADING EDGE OF THE 850MB MOISTURE TRANSPORT. CONVECTION HAS BEEN WEAKENING AS THE CELLS HAVE MOVED NORTH INTO MORE STABLE AIR. HOWEVER...RAIN HAS BECOME MORE WIDESPREAD THAN EXPECTED SO BUMPED UP POPS AND LOWERED TEMPS A BIT IN OUR SOUTHERN COUNTIES. STILL SOME UNCERTAINTY AS TO HOW FAR NORTH THE PRECIP WILL GET THIS AFTERNOON...BUT CONTINUED TO KEEP POPS IN THE CHANCE CATEGORY UP TO THE HIGHWAY 2 CORRIDOR. UPDATE ISSUED AT 937 AM CDT MON JUN 16 2014 A FEW SCATTERED SHOWERS CONTINUES ACROSS THE SOUTHERN COUNTIES THIS MORNING. SHORT RANGE MODELS ARE NOT HANDLING THE MORNING CONVECTION ACROSS THE DAKOTAS PARTICULARLY WELL...BUT THINK THE TREND OF SCATTERED ACTIVITY SLOWLY RAMPING UP OVER THE SOUTHERN COUNTIES WILL CONTINUE. MADE SOME TWEAKS TO POPS FOR TODAY...BUT KEPT THE OVERALL INCREASING FROM 20S TO 50S GOING. WILL CONTINUE TO KEEP TEMPS ON TRACK TO RISE INTO THE 70S. UPDATE ISSUED AT 652 AM CDT MON JUN 16 2014 UPDATED THE POPS ACROSS SE ND AS 850MB MOISTURE ADVECTION HAS BEGUN IN EARNEST...DEVELOPING SOME ISOLATED THUNDER ACROSS NE SD. OTHERWISE STILL EXPECTING MORE ROBUST CONVECTION IN THE 17Z TO 20Z TIME FRAME ACROSS SE ND AND MOVING INTO WCNTRL MN LATE THIS AFTERNOON. MODEL TRENDS HAVE BEEN EXPANDING LIGHTER CONVECTIVE ACTIVITY TO THE NORTH...UP TO HWY 2...FOR THIS AFTERNOON. THE STRONGER CELLS ARE STILL EXPECTED NEAR THE ND SD BORDER WHERE STRONGER INSTABILITY AND HIGHER SHEAR WILL RESIDE. && .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 347 AM CDT MON JUN 16 2014 ACTIVE WEATHER PATTERN CONTINUES WITH THE THREAT FOR MORE SHOWERS AND THUNDERSTORMS TO IMPACT THE SOUTHERN HALF OF THE CWFA TODAY AND TUESDAY. WITH GOOD SOLAR TODAY WITH CLEAR SKIES ALLOWING TEMPS TO CLIMB INTO THE UPPER 70S TO LOW 80S SOUTH. THE SYNOPTIC SCALE MODELS ARE IN GOOD AGREEMENT WITH MOISTURE TRANSPORT TO THE NORTH ON 20 TO 30KT 850MB JET AS PWATS GO FROM AROUND 0.75" AT 12Z TO 1.5" BY 21Z. THIS INCREASE OF MOISTURE COMBINED WITH SHORTWAVE RIDING ALONG IN THE 500MB SW FLOW SHOULD INITIATE CONVECTION IN C SD EARLY THIS AFTN...IDEA REINFORCED BY CURRENT RAP AND HRRR RUNS. ML CAPES UP TO 2000 J/KG ALONG THE SD ND BORDER AND 0-6KM BULK SHEAR VALUES OF 35 TO 45 KTS SOME STRONG TO POTENTIALLY SEVERE STORMS POSSIBLE. HOW CONVECTION EVOLVES REMAINS A BIT MORE UNCERTAIN...AS THE MOISTURE SOURCE MAYBE CUT OFF FROM THE EXPECTED CONVECTION ACROSS E SD AND S MN. THE CHC FOR MORE SHOWERS AND THUNDERSTORMS CONTINUES ACROSS THE SOUTHERN FA ON TUESDAY AS INSTABILITY/MOISTURE PERSIST UNDER THE SW FLOW AND THE NEXT SHORT WAVE MOVES INTO THE AREA FROM THE HIGH PLAINS. SPC HAS THIS AREA IN THEIR SLIGHT RISK ON THE DAY 2 CONVECTIVE OUTLOOK. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 347 AM CDT MON JUN 16 2014 TUESDAY NIGHT-WEDNESDAY NIGHT...500MB RIDGING PUSHES BRIEFLY INTO THE AREA MAKING WEDNESDAY THE WARMEST DAY OF THE WEEK AS 850 TEMPS APPROACH 20C. BY WEDNESDAY PM THE 500MB UPPER LOW WORKS CLOSER TO THE FA WITH INCREASING LARGE SCALE FORCING AND INSTABILITY EXPECTED TO BRING A BAND OF PCPN ACROSS THE FORECAST AREA AS THE WARM FRONT LIFTS NORTH OVERNIGHT. ONCE AGAIN BULK SHEAR VALUES AND MODERATE INSTABILITY WILL BE ENOUGH FOR STORMS TO BE SEVERE...AREA IN THE SLIGHT RISK ON SPC DAY 3 OUTLOOK. THURSDAY-SUNDAY...THERE WILL BE AN UPPER LOW TO THE WEST OF THE REGION TO START THE PERIOD. MODELS REMAIN PERSISTENT WITH HOW THEY HANDLE THIS FEATURE THROUGH THIS PERIOD. THE 00Z GFS/GEM/DGEX PROPAGATE THIS FEATURE VERY SLOWLY ACROSS THE NORTHERN PLAINS...WHILE THE ECMWF IS MORE PROGRESSIVE. THERE WILL LIKELY BE PRECIP ON THURSDAY...BUT LESS CERTAINTY FRIDAY-SUNDAY. TEMPERATURES WILL ALSO BE DEPENDENT ON HOW QUICKLY THE UPPER LOW PROPAGATES EASTWARD. THE POTENTIAL WILL EXIST FOR MORE HEAVY RAINFALL. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1234 PM CDT MON JUN 16 2014 VFR CONDITIONS THROUGH THE FORECAST PERIOD...MAIN CHALLENGE BEING VCTS...PLACED AT VALLEY AIR FIELDS THIS EVENING. OTHERWISE LIGHT WINDS MOSTLY S-SW THIS AFTERNOON TURNING TO E-NE TONIGHT AS LOW PRESSURE TRANSITS SOUTH OF THE REGION. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...JR SHORT TERM...JK LONG TERM...TG/JK AVIATION...WJB
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
937 AM CDT MON JUN 16 2014 .UPDATE... ISSUED AT 937 AM CDT MON JUN 16 2014 A FEW SCATTERED SHOWERS CONTINUES ACROSS THE SOUTHERN COUNTIES THIS MORNING. SHORT RANGE MODELS ARE NOT HANDLING THE MORNING CONVECTION ACROSS THE DAKOTAS PARTICULARLY WELL...BUT THINK THE TREND OF SCATTERED ACTIVITY SLOWLY RAMPING UP OVER THE SOUTHERN COUNTIES WILL CONTINUE. MADE SOME TWEAKS TO POPS FOR TODAY...BUT KEPT THE OVERALL INCREASING FROM 20S TO 50S GOING. WILL CONTINUE TO KEEP TEMPS ON TRACK TO RISE INTO THE 70S. UPDATE ISSUED AT 652 AM CDT MON JUN 16 2014 UPDATED THE POPS ACROSS SE ND AS 850MB MOISTURE ADVECTION HAS BEGUN IN EARNEST...DEVELOPING SOME ISOLATED THUNDER ACROSS NE SD. OTHERWISE STILL EXPECTING MORE ROBUST CONVECTION IN THE 17Z TO 20Z TIME FRAME ACROSS SE ND AND MOVING INTO WCNTRL MN LATE THIS AFTERNOON. MODEL TRENDS HAVE BEEN EXPANDING LIGHTER CONVECTIVE ACTIVITY TO THE NORTH...UP TO HWY 2...FOR THIS AFTERNOON. THE STRONGER CELLS ARE STILL EXPECTED NEAR THE ND SD BORDER WHERE STRONGER INSTABILITY AND HIGHER SHEAR WILL RESIDE. && .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 347 AM CDT MON JUN 16 2014 ACTIVE WEATHER PATTERN CONTINUES WITH THE THREAT FOR MORE SHOWERS AND THUNDERSTORMS TO IMPACT THE SOUTHERN HALF OF THE CWFA TODAY AND TUESDAY. WITH GOOD SOLAR TODAY WITH CLEAR SKIES ALLOWING TEMPS TO CLIMB INTO THE UPPER 70S TO LOW 80S SOUTH. THE SYNOPTIC SCALE MODELS ARE IN GOOD AGREEMENT WITH MOISTURE TRANSPORT TO THE NORTH ON 20 TO 30KT 850MB JET AS PWATS GO FROM AROUND 0.75" AT 12Z TO 1.5" BY 21Z. THIS INCREASE OF MOISTURE COMBINED WITH SHORTWAVE RIDING ALONG IN THE 500MB SW FLOW SHOULD INITIATE CONVECTION IN C SD EARLY THIS AFTN...IDEA REINFORCED BY CURRENT RAP AND HRRR RUNS. ML CAPES UP TO 2000 J/KG ALONG THE SD ND BORDER AND 0-6KM BULK SHEAR VALUES OF 35 TO 45 KTS SOME STRONG TO POTENTIALLY SEVERE STORMS POSSIBLE. HOW CONVECTION EVOLVES REMAINS A BIT MORE UNCERTAIN...AS THE MOISTURE SOURCE MAYBE CUT OFF FROM THE EXPECTED CONVECTION ACROSS E SD AND S MN. THE CHC FOR MORE SHOWERS AND THUNDERSTORMS CONTINUES ACROSS THE SOUTHERN FA ON TUESDAY AS INSTABILITY/MOISTURE PERSIST UNDER THE SW FLOW AND THE NEXT SHORT WAVE MOVES INTO THE AREA FROM THE HIGH PLAINS. SPC HAS THIS AREA IN THEIR SLIGHT RISK ON THE DAY 2 CONVECTIVE OUTLOOK. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 347 AM CDT MON JUN 16 2014 TUESDAY NIGHT-WEDNESDAY NIGHT...500MB RIDGING PUSHES BRIEFLY INTO THE AREA MAKING WEDNESDAY THE WARMEST DAY OF THE WEEK AS 850 TEMPS APPROACH 20C. BY WEDNESDAY PM THE 500MB UPPER LOW WORKS CLOSER TO THE FA WITH INCREASING LARGE SCALE FORCING AND INSTABILITY EXPECTED TO BRING A BAND OF PCPN ACROSS THE FORECAST AREA AS THE WARM FRONT LIFTS NORTH OVERNIGHT. ONCE AGAIN BULK SHEAR VALUES AND MODERATE INSTABILITY WILL BE ENOUGH FOR STORMS TO BE SEVERE...AREA IN THE SLIGHT RISK ON SPC DAY 3 OUTLOOK. THURSDAY-SUNDAY...THERE WILL BE AN UPPER LOW TO THE WEST OF THE REGION TO START THE PERIOD. MODELS REMAIN PERSISTENT WITH HOW THEY HANDLE THIS FEATURE THROUGH THIS PERIOD. THE 00Z GFS/GEM/DGEX PROPAGATE THIS FEATURE VERY SLOWLY ACROSS THE NORTHERN PLAINS...WHILE THE ECMWF IS MORE PROGRESSIVE. THERE WILL LIKELY BE PRECIP ON THURSDAY...BUT LESS CERTAINTY FRIDAY-SUNDAY. TEMPERATURES WILL ALSO BE DEPENDENT ON HOW QUICKLY THE UPPER LOW PROPAGATES EASTWARD. THE POTENTIAL WILL EXIST FOR MORE HEAVY RAINFALL. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 652 AM CDT MON JUN 16 2014 VFR TODAY WITH INCREASING CLOUDS AS THE NEXT ROUND OF SHOWERS AND THUNDERSTORMS LIFTS NORTHEAST ACROSS THE AREA. ADDED VCTS AT FAR THIS AFTERNOON...CONFIDENCE LOWER ELSEWHERE. CONVECTION ENDS WITH SUNDOWN THIS EVENING. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...JR SHORT TERM...JK LONG TERM...TG/JK AVIATION...JK
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
653 AM CDT MON JUN 16 2014 .UPDATE... ISSUED AT 652 AM CDT MON JUN 16 2014 UPDATED THE POPS ACROSS SE ND AS 850MB MOISTURE ADVECTION HAS BEGUN IN EARNEST...DEVELOPING SOME ISOLATED THUNDER ACROSS NE SD. OTHERWISE STILL EXPECTING MORE ROBUST CONVECTION IN THE 17Z TO 20Z TIME FRAME ACROSS SE ND AND MOVING INTO WCNTRL MN LATE THIS AFTERNOON. MODEL TRENDS HAVE BEEN EXPANDING LIGHTER CONVECTIVE ACTIVITY TO THE NORTH...UP TO HWY 2...FOR THIS AFTERNOON. THE STRONGER CELLS ARE STILL EXPECTED NEAR THE ND SD BORDER WHERE STRONGER INSTABILITY AND HIGHER SHEAR WILL RESIDE. && .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 347 AM CDT MON JUN 16 2014 ACTIVE WEATHER PATTERN CONTINUES WITH THE THREAT FOR MORE SHOWERS AND THUNDERSTORMS TO IMPACT THE SOUTHERN HALF OF THE CWFA TODAY AND TUESDAY. WITH GOOD SOLAR TODAY WITH CLEAR SKIES ALLOWING TEMPS TO CLIMB INTO THE UPPER 70S TO LOW 80S SOUTH. THE SYNOPTIC SCALE MODELS ARE IN GOOD AGREEMENT WITH MOISTURE TRANSPORT TO THE NORTH ON 20 TO 30KT 850MB JET AS PWATS GO FROM AROUND 0.75" AT 12Z TO 1.5" BY 21Z. THIS INCREASE OF MOISTURE COMBINED WITH SHORTWAVE RIDING ALONG IN THE 500MB SW FLOW SHOULD INITIATE CONVECTION IN C SD EARLY THIS AFTN...IDEA REINFORCED BY CURRENT RAP AND HRRR RUNS. ML CAPES UP TO 2000 J/KG ALONG THE SD ND BORDER AND 0-6KM BULK SHEAR VALUES OF 35 TO 45 KTS SOME STRONG TO POTENTIALLY SEVERE STORMS POSSIBLE. HOW CONVECTION EVOLVES REMAINS A BIT MORE UNCERTAIN...AS THE MOISTURE SOURCE MAYBE CUT OFF FROM THE EXPECTED CONVECTION ACROSS E SD AND S MN. THE CHC FOR MORE SHOWERS AND THUNDERSTORMS CONTINUES ACROSS THE SOUTHERN FA ON TUESDAY AS INSTABILITY/MOISTURE PERSIST UNDER THE SW FLOW AND THE NEXT SHORT WAVE MOVES INTO THE AREA FROM THE HIGH PLAINS. SPC HAS THIS AREA IN THEIR SLIGHT RISK ON THE DAY 2 CONVECTIVE OUTLOOK. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 347 AM CDT MON JUN 16 2014 TUESDAY NIGHT-WEDNESDAY NIGHT...500MB RIDGING PUSHES BRIEFLY INTO THE AREA MAKING WEDNESDAY THE WARMEST DAY OF THE WEEK AS 850 TEMPS APPROACH 20C. BY WEDNESDAY PM THE 500MB UPPER LOW WORKS CLOSER TO THE FA WITH INCREASING LARGE SCALE FORCING AND INSTABILITY EXPECTED TO BRING A BAND OF PCPN ACROSS THE FORECAST AREA AS THE WARM FRONT LIFTS NORTH OVERNIGHT. ONCE AGAIN BULK SHEAR VALUES AND MODERATE INSTABILITY WILL BE ENOUGH FOR STORMS TO BE SEVERE...AREA IN THE SLIGHT RISK ON SPC DAY 3 OUTLOOK. THURSDAY-SUNDAY...THERE WILL BE AN UPPER LOW TO THE WEST OF THE REGION TO START THE PERIOD. MODELS REMAIN PERSISTENT WITH HOW THEY HANDLE THIS FEATURE THROUGH THIS PERIOD. THE 00Z GFS/GEM/DGEX PROPAGATE THIS FEATURE VERY SLOWLY ACROSS THE NORTHERN PLAINS...WHILE THE ECMWF IS MORE PROGRESSIVE. THERE WILL LIKELY BE PRECIP ON THURSDAY...BUT LESS CERTAINTY FRIDAY-SUNDAY. TEMPERATURES WILL ALSO BE DEPENDENT ON HOW QUICKLY THE UPPER LOW PROPAGATES EASTWARD. THE POTENTIAL WILL EXIST FOR MORE HEAVY RAINFALL. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 652 AM CDT MON JUN 16 2014 VFR TODAY WITH INCREASING CLOUDS AS THE NEXT ROUND OF SHOWERS AND THUNDERSTORMS LIFTS NORTHEAST ACROSS THE AREA. ADDED VCTS AT FAR THIS AFTERNOON...CONFIDENCE LOWER ELSEWHERE. CONVECTION ENDS WITH SUNDOWN THIS EVENING. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...JK SHORT TERM...JK LONG TERM...TG/JK AVIATION...JK
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
349 AM CDT MON JUN 16 2014 .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 347 AM CDT MON JUN 16 2014 ACTIVE WEATHER PATTERN CONTINUES WITH THE THREAT FOR MORE SHOWERS AND THUNDERSTORMS TO IMPACT THE SOUTHERN HALF OF THE CWFA TODAY AND TUESDAY. WITH GOOD SOLAR TODAY WITH CLEAR SKIES ALLOWING TEMPS TO CLIMB INTO THE UPPER 70S TO LOW 80S SOUTH. THE SYNOPTIC SCALE MODELS ARE IN GOOD AGREEMENT WITH MOISTURE TRANSPORT TO THE NORTH ON 20 TO 30KT 850MB JET AS PWATS GO FROM AROUND 0.75" AT 12Z TO 1.5" BY 21Z. THIS INCREASE OF MOISTURE COMBINED WITH SHORTWAVE RIDING ALONG IN THE 500MB SW FLOW SHOULD INITIATE CONVECTION IN C SD EARLY THIS AFTN...IDEA REINFORCED BY CURRENT RAP AND HRRR RUNS. ML CAPES UP TO 2000 J/KG ALONG THE SD ND BORDER AND 0-6KM BULK SHEAR VALUES OF 35 TO 45 KTS SOME STRONG TO POTENTIALLY SEVERE STORMS POSSIBLE. HOW CONVECTION EVOLVES REMAINS A BIT MORE UNCERTAIN...AS THE MOISTURE SOURCE MAYBE CUT OFF FROM THE EXPECTED CONVECTION ACROSS E SD AND S MN. THE CHC FOR MORE SHOWERS AND THUNDERSTORMS CONTINUES ACROSS THE SOUTHERN FA ON TUESDAY AS INSTABILITY/MOISTURE PERSIST UNDER THE SW FLOW AND THE NEXT SHORT WAVE MOVES INTO THE AREA FROM THE HIGH PLAINS. SPC HAS THIS AREA IN THEIR SLIGHT RISK ON THE DAY 2 CONVECTIVE OUTLOOK. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 347 AM CDT MON JUN 16 2014 TUESDAY NIGHT-WEDNESDAY NIGHT...500MB RIDGING PUSHES BRIEFLY INTO THE AREA MAKING WEDNESDAY THE WARMEST DAY OF THE WEEK AS 850 TEMPS APPROACH 20C. BY WEDNESDAY PM THE 500MB UPPER LOW WORKS CLOSER TO THE FA WITH INCREASING LARGE SCALE FORCING AND INSTABILITY EXPECTED TO BRING A BAND OF PCPN ACROSS THE FORECAST AREA AS THE WARM FRONT LIFTS NORTH OVERNIGHT. ONCE AGAIN BULK SHEAR VALUES AND MODERATE INSTABILITY WILL BE ENOUGH FOR STORMS TO BE SEVERE...AREA IN THE SLIGHT RISK ON SPC DAY 3 OUTLOOK. THURSDAY-SUNDAY...THERE WILL BE AN UPPER LOW TO THE WEST OF THE REGION TO START THE PERIOD. MODELS REMAIN PERSISTENT WITH HOW THEY HANDLE THIS FEATURE THROUGH THIS PERIOD. THE 00Z GFS/GEM/DGEX PROPAGATE THIS FEATURE VERY SLOWLY ACROSS THE NORTHERN PLAINS...WHILE THE ECMWF IS MORE PROGRESSIVE. THERE WILL LIKELY BE PRECIP ON THURSDAY...BUT LESS CERTAINTY FRIDAY-SUNDAY. TEMPERATURES WILL ALSO BE DEPENDENT ON HOW QUICKLY THE UPPER LOW PROPAGATES EASTWARD. THE POTENTIAL WILL EXIST FOR MORE HEAVY RAINFALL. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1141 PM CDT SUN JUN 15 2014 VFR THROUGH THE PERIOD. SKIES WILL CLEAR OFF ACROSS THE FAR NORTH IN THE NEXT HOUR OR SO. SHOULD SEE GENERALLY CLEAR SKIES UNTIL AFTERNOON WHEN CLOUDS THICKEN BUT IN VFR RANGE. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ SHORT TERM...JK LONG TERM...TG/JK AVIATION...VOELKER
AREA FORECAST DISCUSSION
NWS PENDLETON OR
215 PM PDT MON JUN 16 2014 .SHORT TERM...TONIGHT THROUGH THURSDAY. LOW PRESSURE WILL MOVE ACROSS THE AREA THIS EVENING PRODUCING SHOWERS ALONG WITH ISOLD TSRA. WITH THE LOSS OF DAYTIME HEATING ANY TSRA SHOULD DISSIPATE AND THE CHANCES FOR SHOWERS SHOULD LESSEN. THE LOW PRESSURE SYSTEM SLOWLY MOVES INTO IDAHO TOMORROW BUT RAP AROUND MOISTURE WILL PERSIST OVER THE EASTERN THIRD OF OUR AREA SO THE CHANCE FOR SHOWERS WILL BE THE GREATEST OVER THE BLUE/WALLOWA MOUNTAINS INTO TUESDAY NIGHT. BY WEDNESDAY THE LOW WILL CONTINUE MOVING AWAY FROM THE REGION WITH DRIER CONDITIONS EXPECTED FOR MUCH OF THE TWO STATE AREA ON WEDNESDAY EXCEPT FOR THE EASTERN MOUNTAINS. OTHERWISE BY THURSDAY A RIDGE OF HIGH PRESSURE BUILDS INTO WA/OR AND OUR AREA SHOULD EXPERIENCE MOSTLY DRY CONDITIONS AND WARMER TEMPERATURES. .LONG TERM...THURSDAY NIGHT THROUGH MONDAY...THE REGION WILL BECOME UNDER THE INFLUENCE OF INCREASING S-SW FLOW THROUGH THE PERIOD AS AN UPPER LEVEL TROUGH BECOMES ESTABLISHED AND REMAINS OFFSHORE OF THE PACIFIC NW. THIS WILL RESULT IN WARMING TEMPERATURES AND INCREASING MOISTURE/INSTABILITY. TEMPERATURES WILL WARM THROUGH THE PERIOD TO ABOVE NORMAL WITH LOWER ELEVATION HIGH TEMPERATURES IN THE LOWER 90S BY SUNDAY AND OVERNIGHT LOWS 55-60F. AT THE SAME TIME THERE WILL BE A GRADUAL MOISTENING OF THE LOW LEVELS SUCH THAT THERE MAY BE ENOUGH INSTABILITY FOR DIURNALLY ENHANCED THUNDERSTORMS...MAINLY OVER THE MOUNTAINS OF CENTRAL AND NORTHEAST OREGON FRIDAY AND SATURDAY. BY SUNDAY AND MONDAY THE THUNDERSTORM THREAT MAY EXTEND NORTHWARD ALONG THE WASHINGTON CASCADE CREST. FOR NOW WENT WITH SLIGHT CHANCE POPS AND KEPT THE LOWER BASINS DRY BECAUSE THE ECMWF MODEL WAS LESS EMPHATIC ABOUT THE DEVELOPING SOUTHERLY FLOW...KEEPING THE FLOW MORE WESTERLY AND A LITTLE DRIER/MORE STABLE. 78 && .AVIATION...00Z TAFS...VFR CONDITIONS WILL PREVAIL THROUGH 00Z WEDNESDAY....SCATTERED SHOWERS ARE DEVELOPING AS EXPECTED THIS AFTERNOON. PLAN TO HANDLE THESE WITH VCSH INTO THE EARLY NIGHTTIME HOURS. STRONGER SHOWERS COULD PRODUCE OCNL LTG STRIKES. WEST WINDS OF 10-25KT WILL CONTINUE INTO THE EVENING AND THEN SUBSIDE OVERNIGHT BEFORE PICKING UP AGAIN AFTER 15-18Z TUESDAY. CEILINGS WILL BE MOSTLY BKN AT 4-6 THOUSAND FEET AND BKN-OVC AT 8-10 THOUSAND FEET. && .PRELIMINARY POINT TEMPS/POPS... PDT 45 62 49 76 / 20 20 10 10 ALW 50 64 53 77 / 20 20 20 10 PSC 52 70 53 82 / 20 20 10 10 YKM 46 71 50 78 / 20 20 10 10 HRI 49 67 50 80 / 20 20 10 10 ELN 47 70 51 75 / 30 20 10 10 RDM 34 61 35 73 / 20 20 0 10 LGD 43 55 45 70 / 30 30 20 20 GCD 39 56 41 73 / 20 20 20 10 DLS 51 70 53 78 / 20 20 10 10 && .PDT WATCHES/WARNINGS/ADVISORIES... OR...NONE. WA...NONE. && FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT... WWW.WEATHER.GOV/PENDLETON $$ 97/78/78
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1047 PM EDT TUE JUN 17 2014 .SYNOPSIS... CENTRAL PA WILL REMAIN ON THE NORTHERN PERIPHERY OF A SUBTROPICAL RIDGE CENTERED OVER THE SOUTHEAST STATES THROUGH AT LEAST WEDNESDAY. SLIGHTLY COOLER AND DRIER AIR IS EXPECTED TO WORK INTO THE AREA FOR THE LATTER PART OF THE WEEK. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... SEVERE THUNDERSTORM WATCH 314 CONTINUES IN EFFECT FOR A FEW MORE HOURS /UNTIL 05Z/ ACROSS THE NORTHERN 2 LAYERS OF COUNTIES IN OUR CWA. BKN LINE OF STRONG TO SEVERE TSRA CURRENTLY TRACKING QUICKLY ESE FROM NWRN PENN...VIA THE FAIRLY STRONG 40 KT 0-6 KM BULK SHEAR. THE STRONG...MID-LEVEL CAP WITH 700 MB TEMPS AOA 8.5C ACROSS THE SOUTHERN HALF OF PENN WILL SLOWLY SAG SOUTH/WEAKEN OVERNIGHT ALLOWING THE TSRA TO MAKE IT AS FAR SOUTH /ALBEIT IN A SLIGHTLY WEAKENED STATE/ AS THE INTERSTATE 80 CORRIDOR AFTER 06Z. VERY LATE TONIGHT...A FEW ISOLATED TSRA SHOULD LINGER ACROSS THE NW 2/3RDS OF THE CWA...WHILE THE FAR SE ZONES SEE CLEAR TO PARTLY CLOUDY SKIES OVERNIGHT. 850 MB MOISTURE FLUX VIA THE 15Z SREF IS NEAR ITS PEAK AT AN IMPRESSIVE...5-6 STANDARD DEVIATIONS /ACROSS THE NRN HALF OF THE CWA...AND AT THE SOUTHERN EDGE OF A RIBBON OF 50 KT 850 MB WINDS/. POTENTIAL FOR DAMAGING STRAIGHT LINE WINDS WILL CONTINUE NEAR THE LEADING EDGE /AND WITHIN THE CORES/ OF THE MORE INTENSE STORMS /ESP ACROSS THE NW MTNS/ CONSIDERING THE DEEP LAYER SHEAR...AND CAPES AOA 1200 J/KG /VIA THE SREF/. A POCKET OF 0-1KM ENERGY HELICITY INDEX AROUND 2 MS/S2 WILL STAY INTACT FOR THE NEXT HOUR OR SO ACROSS THE MTNS NORTH OF KIPT. THIS WILL BRING THE CHC FOR A TSRA OR TWO IN THE BKN LINE TO DEVELOP SUPERCELL STRUCTURE. IT WILL BE ANOTHER VERY MUGGY OVERNIGHT. LOWS WELL UP IN THE 60S WILL BE SOME 10-15 DEG ABOVE NORMAL. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/... LOW LEVEL NW FLOW ON WEDNESDAY WILL INITIALLY BRING SLIGHTLY DRIER AIR INTO THE REGION...BUT A RETURN SOUTHERLY FLOW IS MADE TO RAPIDLY REDEVELOP BY AFTERNOON OVER OVER WESTERN AREAS. SHORT RANGE MODEL SURFACE PRESSURE PROGS SUGGEST WE WILL BE BASICALLY IN A COL BETWEEN LOW PRESSURE EAST AND WEST OF US...AND HIGH PRESSURE NORTH AND SOUTH. MODELS ONCE AGAIN GENERATE A RESPECTABLE AMOUNT OF INSTABILITY SO MORE DIURNALLY FAVORED CONVECTION SHOULD BE IN STORE. THE IMPLIED PRESENCE OF A LOW LEVEL BOUNDARY OVER SWRN PA SUGGESTS THAT THE BEST CHANCE OF SHOWERS WILL WEST...WITH LESSER CHANCES FURTHER EAST. TEMPERATURES MAY BE A DEGREE OR TWO COOLER THAN TODAY...NOT SIGNIFICANTLY DIFFERENT. && .LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/... UPPER RIDGE CURRENTLY OVER THE EASTERN U.S. IS FORECAST TO BE SQUASHED BY AN UPPER LOW FORECAST TO DEEPEN OVER EASTERN QUEBEC MIDWEEEK AND DIG INTO THE CANADIAN MARITIMES BY THE WEEKEND. THIS UPPER LOW WILL PUSH A COLD FRONT SOUTHWARD INTO THE AREA DURING THE LATTER HALF OF THE WEEK...BRINGING AN END TO THE SULTRY TEMPS. THE FRONT IS FCST TO STALL JUST SOUTH OF PA AND SERVE AS A POSSIBLE FOCUS FOR CONVECTION. SEVERAL SHORTWAVES TRAVELING THROUGH THE UPPER FLOW WILL PRODUCE A SERIES OF SFC WAVES ALONG THE FRONT AS IT LIFTS NORTH AS A WARM FRONT AT SOME POINT OVER THE WEEKEND INTO EARLY NEXT WEEK. THIS LOOKS TO SUPPORT AN UNSETTLED PATTERN...THOUGH CERTAINTY OF PCPN ON ANY GIVEN DAY REMAINS IN THE CHANCE CATEGORY GIVEN THE TIME FRAME AND UNCERTAINTY IN THE OVERALL PATTERN. && .AVIATION /03Z WEDNESDAY THROUGH SUNDAY/... BROKEN LINE OF STRONG TO SEVERE TSRA AT 02Z TRACKING ESE FROM NWRN PENN...WILL IMPACT KBFD THROUGH 04Z BEFORE PUSHING EASTWARD AND SOUTHWARD TOWARD KELM-KDUJ. THOUGH MID-LEVEL CAP INCREASES AS ONE HEADS SOUTHWARD...THIS LINE WILL CONTINUE TO SAG SLOWLY SOUTHWARD AFTER MIDNIGHT...ALLOWING THE TSRA TO APPROACH KFIG-KUNV-KIPT AFTER 06Z. THE LINE WILL CONTINUE TO WEAKEN FURTHER AFTER THAT...WITH POTENTIAL FOR SCT SHOWERS FROM KJST-KAOO AND POSS A TSTM AROUND 08-10Z IN VICINITY OFF KMDT-KLNS IF THE MESOSCALE HRRR MODEL HOLDS TRUE /BUT DIDNT MENTION THAT IN TAFS JUST YET WITH FAIR AMOUNT OF UNCERTAINTY IN BOTH STRENGTH AND LOCATION 6+ HRS OUT/. OTHERWISE OVERNIGHT...WARM AND HUMID CONDITIONS CONTINUE. BEHIND THE LINE OF STORMS MAINLY ACROSS THE NW MTNS...SHOULD SEE A LOWER DECK OF MVFR STRATOCU DEVELOP. OTHERWISE NO WIDESPREAD REDUCTIONS ARE EXPECTED. WEDNESDAY SHOULD REMAIN FAIRLY QUIET THROUGH THE FIRST HALF...BUT WARM AND HUMID AIRMASS WILL AGAIN PROVIDE ENOUGH INSTABILITY TO KICK OFF MAINLY AFTERNOON CONVECTION THAT WILL LINGER INTO THE EVENING HOURS. MOST NUMEROUS SHOWERS/TSTMS WILL BE IN THE SW...WITH SCATTERED CONVECTION DEVELOPING ELSEWHERE...ALL PROVIDING LOCAL REDUCTIONS. OUTLOOK... THU...VFR WITH AREAS OF MVFR AND SCT SHOWERS/TSTMS. FRI...NO SIG WX. SAT-SUN...VFR WITH AREAS OF MVFR AND SCT SHOWERS/TSTMS. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE/LAMBERT NEAR TERM...LAMBERT SHORT TERM...LA CORTE LONG TERM...GARTNER/MARTIN AVIATION...RXR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
410 PM EDT MON JUN 16 2014 .SYNOPSIS... AN APPROACHING WARM FRONT WILL BRING A RETURN OF HUMIDITY AND THE CHANCE FOR SHOWERS AND SCATTERED THUNDERSTORMS. THE WARM AND MUGGY CONDITIONS WITH OCCASIONAL CHANCES FOR SHOWERS OR THUNDERSTORMS WILL CONTINUE FOR MUCH OF THIS WEEK. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... DEWPOINTS IN THE MID 60S PRETTY MUCH MARK THE EDGE OF THE ADVANCING CU FIELD AS MOISTURE SURGES IN FROM THE OHIO VALLEY. THE RADAR IS BECOMING MORE ACTIVE WITH THE NEAREST THUNDER SHOWER NEAR JOHNSTOWN...BUT BECOMING MUCH MORE ACTIVE JUST OFF TO OUR WEST. THE RAP ALREADY INDICATES CAPES IN EXCESS OF 1000J OVER CENTRAL PA. LIMITING THE CONVECTION IS THE LACK OF A LOW LEVEL FOCUS AND WEAK MID LEVEL LAPSE RATES. IT SUPPORTS THE FORECAST OF SCATTERED SHOWERS AND STORMS...WITH LITTLE CERTAINTY AS TO THE AREAS THAT WILL BE MOST FAVORED TO RECEIVE RAIN. THE HRRR HAS BEEN SHOWING INCREASING ACTIVITY THROUGH MID AFTERNOON NOW FOR SEVERAL RUNS...BUT THE PLACEMENT OF THE PROGGED RADAR FEATURES HAS BEEN VERY INCONSISTENT. SO I WILL STICK WITH MY FORECAST FOR SCATTERED ACTIVITY. HIGHS IN THE 80S ARE A CERTAINTY EVERYWHERE...WITH SOME READINGS NUDGING 90 LIKELY OVER MY SERN ZONES. IF IT DOES TOP 90...IT WILL BE THE FIRST DAY TO DO SO THIS YEAR...WHICH FOR MOST LOCATIONS IS ABOUT 2 WEEKS LATER THAN NORMAL. DUE TO THE WEAK FORCING...THE CONVECTION WILL DIMINISH RATHER QUICKLY WITH THE LOSS OF HEATING...LEAVING A MUGGY BUT MAINLY FAIR OVERNIGHT. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/... FOR TUESDAY...A POTENT SHORTWAVE IS PROGGED TO MOVE THROUGH THE ERN GR LAKES...WITH MOIST-UNSTABLE AIR BEING MADE TO SURGE INTO THE REGION. SREF SHOWS IMPRESSIVE CAPE WHICH CONTINUES INTO THE EVENING...ALONG WITH STRONG MOISTURE FLUX CONVERGENCE MOVING THRU THE ERN LAKES AND NRN PA. MODELS ALSO FORECAST IMPRESSIVE SHEAR WITH LOW LEVEL EHI`S EXCEEDING 3 M2/S2 OVER A WIDE AREA DURING THE MOST UNSTABLE TIME OF DAY. THE LIMITING FEATURE TUESDAY WILL BE VERY WARM MID LEVELS AS GUIDANCE SHOWS US RIGHT ON THE EDGE OF A BUBBLE OF VERY WARM MID LEVEL AIR...AS THE MAIN SHORTWAVE ENERGY SLIDES JUST NORTH OF THE AREA. VALUES OF EHI THIS HIGH ARE RARE IN THIS REGION...AND WE`LL HAVE TO CLOSELY MONITOR TRENDS FOR THE POTENTIAL OF A SIGNIFICANT SEVERE WEATHER OUTBREAK FORMING OVER OR HEADING SE FROM THE UPSTREAM GREAT LAKES. OTHERWISE TUESDAY LOOKS LIKE ANOTHER VERY WARM TO HOT AND RATHER HUMID DAY WITH WITH HIGHS ONCE AGAIN IN THE 80S TO AROUND 90. && .LONG TERM /TUESDAY NIGHT THROUGH MONDAY/... BROAD UPPER RIDGE OVER THE EASTERN HALF OF THE COUNTY...WITH 588DM LINE NOSING NWD INTO SWRN PA...WILL KEEP A FORECAST OF WARM TO HOT WEATHER ON TRACK THROUGH AT LEAST MID WEEK. AN UPPER LOW IS FORECAST TO DEVELOP OVER EASTERN QUEBEC AND THE CANADIAN MARITIMES BY MIDWEEK WHICH SHOULD SERVE TO PUSH A FRONT SOUTHWARD THROUGH NEW ENGLAND/NEW YORK STATE LATE IN THE WEEK THEN STALL ACROSS THE MID ATLANTIC. THIS BOUNDARY SHOULD LEAD TO MORE THAN JUST ISOLATED/POP-UP AFTN TSTMS ESP WITH THE LOW LEVEL MOISTURE/HIGH SFC DEWPOINTS THAT WILL BE IN PLACE. HAVE INCLUDED POPS FOR SCATTERED CONVECTION...AND LIKELY WHERE THERE IS SUFFICIENT CONFIDENCE AT THIS TIME RANGE ...EACH DAY THROUGH NEXT WEEKEND. EXPECT VERY WARM 850 MB TEMPERATURES ESPECIALLY IN THE WED-THU TIME PERIOD. 90 DEGREE READINGS LIKELY IN SUSQ VALLEY AND MAY MAKE A PUSH ALL THE WAY TOWARDS STATE COLLEGE ON WEDNESDAY. DEW POINTS WILL BE IN ABOVE 60F MOST OF THE WEEK...SO EXPECT UNCOMFORTABLE AFTERNOONS...THOUGH BELOW ANY HEAT ADVISORY CRITERIA AT THIS TIME. && .AVIATION /20Z MONDAY THROUGH SATURDAY/... STRONG SFC HEATING AND INCREASING MOISTURE WILL CONTRIBUTE TO DEVELOPING ADEQUATE INSTABILITY TO GENERATE SCATTERED SHOWERS AND THUNDERSTORMS...WITH THE FIRST OF DAY ALREADY AT JST. ACTIVITY WILL BE VERY HIT AND MISS...WITH TERMINALS REMAINING VFR EXCEPT WHERE THE CONVECTION MOVES IN...THEN CONDITIONS COULD BRIEFLY DROP TO IFR OR LOWER. SHOWERS AND STORMS WILL DIMINISH THIS EVENING...BUT AN INCREASINGLY HUMID AIRMASS WILL MAKE FOR SOME FOG/HAZE ISSUES OVERNIGHT WITH VISIBILITIES LIKELY TO DROP BACK INTO THE 2-4 MILE RANGE AT MOST TERMINALS. THESE REDUCED CONDITIONS WILL IMPROVE RAPIDLY AFTER SUNRISE TUESDAY...WITH ALL AIRPORTS GOING VFR BY MID MORNING AND STAYING THAT WAY UNTIL ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS BEGINS TO AFFECT THE AREA TUESDAY AFTERNOON AND EVENING. OUTLOOK... WED-SAT...VFR WITH AREAS OF MVFR AND SCATTERED SHOWERS/THUNDERSTORMS. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE NEAR TERM...LA CORTE SHORT TERM...LA CORTE LONG TERM...LAMBERT/GARTNER AVIATION...LA CORTE
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
214 PM EDT MON JUN 16 2014 .SYNOPSIS... AN APPROACHING WARM FRONT WILL BRING A RETURN OF HUMIDITY AND THE CHANCE FOR SHOWERS AND SCATTERED THUNDERSTORMS. THE WARM AND MUGGY CONDITIONS WITH OCCASIONAL CHANCES FOR SHOWERS OR THUNDERSTORMS WILL CONTINUE FOR MUCH OF THIS WEEK. && .NEAR TERM /THROUGH TONIGHT/... DEWPOINTS IN THE MID 60S PRETTY MUCH MARK THE EDGE OF THE ADVANCING CU FIELD AS MOISTURE SURGES IN FROM THE OHIO VALLEY. THE RADAR IS BECOMING MORE ACTIVE WITH THE NEAREST THUNDER SHOWER NEAR JOHNSTOWN...BUT BECOMING MUCH MORE ACTIVE JUST OFF TO OUR WEST. THE RAP ALREADY INDICATES CAPES IN EXCESS OF 1000J OVER CENTRAL PA. LIMITING THE CONVECTION IS THE LACK OF A LOW LEVEL FOCUS AND WEAK MID LEVEL LAPSE RATES. IT SUPPORTS THE FORECAST OF SCATTERED SHOWERS AND STORMS...WITH LITTLE CERTAINTY AS TO THE AREAS THAT WILL BE MOST FAVORED TO RECEIVE RAIN. THE HRRR HAS BEEN SHOWING INCREASING ACTIVITY THROUGH MID AFTERNOON NOW FOR SEVERAL RUNS...BUT THE PLACEMENT OF THE PROGGED RADAR FEATURES HAS BEEN VERY INCONSISTENT. SO I WILL STICK WITH MY FORECAST FOR SCATTERED ACTIVITY. HIGHS IN THE 80S ARE A CERTAINTY EVERYWHERE...WITH SOME READINGS NUDGING 90 LIKELY OVER MY SERN ZONES. IF IT DOES TOP 90...IT WILL BE THE FIRST DAY TO DO SO THIS YEAR...WHICH FOR MOST LOCATIONS IS ABOUT 2 WEEKS LATER THAN NORMAL. DUE TO THE WEAK FORCING...THE CONVECTION WILL DIMINISH RATHER QUICKLY WITH THE LOSS OF HEATING...LEAVING A MUGGY BUT MAINLY FAIR OVERNIGHT. && .SHORT TERM /TUESDAY/... FOR TUESDAY...A POTENT SHORTWAVE IS PROGGED TO MOVE THROUGH THE ERN GR LAKES...WITH MOIST-UNSTABLE AIR BEING MADE TO SURGE INTO THE REGION. SREF SHOWS IMPRESSIVE CAPE WHICH CONTINUES INTO THE EVENING...ALONG WITH STRONG MOISTURE FLUX CONVERGENCE MOVING THRU THE ERN LAKES AND NRN PA. MODELS ALSO FORECAST IMPRESSIVE SHEAR WITH LOW LEVEL EHI`S EXCEEDING 3 M2/S2 OVER A WIDE AREA DURING THE MOST UNSTABLE TIME OF DAY. THE LIMITING FEATURE TUESDAY WILL BE VERY WARM MID LEVELS AS GUIDANCE SHOWS US RIGHT ON THE EDGE OF A BUBBLE OF VERY WARM MID LEVEL AIR...AS THE MAIN SHORTWAVE ENERGY SLIDES JUST NORTH OF THE AREA. VALUES OF EHI THIS HIGH ARE RARE IN THIS REGION...AND WE`LL HAVE TO CLOSELY MONITOR TRENDS FOR THE POTENTIAL OF A SIGNIFICANT SEVERE WEATHER OUTBREAK FORMING OVER OR HEADING SE FROM THE UPSTREAM GREAT LAKES. OTHERWISE TUESDAY LOOKS LIKE ANOTHER VERY WARM TO HOT AND RATHER HUMID DAY WITH WITH HIGHS ONCE AGAIN IN THS 80S TO AROUND 90. && .LONG TERM /TUESDAY NIGHT THROUGH MONDAY/... FORECAST OF WARM TO HOT WEATHER ON TRACK AS SUMMER LIKE RIDGING JUST TO THE SOUTH OF PA BUT CLOSE ENOUGH TO RESULT IN VERY WARM 850 MB TEMPERATURES ESPECIALLY IN THE WED-THU TIME PERIOD. 90 DEGREE READINGS LIKELY IN SUSQ VALLEY AND MAY MAKE A PUSH ALL THE WAY TOWARDS STATE COLLEGE BY WEDNESDAY AND THURSDAY. DEW POINTS WILL BE ON THE RISE ALL WEEK AS WELL...SO EXPECT SOMEWHAT UNCOMFORTABLE AFTERNOONS...THOUGH BELOW ANY HEAT ADVISORY CRITERIA AT THIS TIME. AN UPPER LOW IS FORECAST TO DEVELOP OVER EASTERN QUEBEC AND THE CANADIAN MARITIMES BY MIDWEEK. THIS LOOKS LIKE IT WILL PUSH A FRONT SOUTHWARD THROUGH NEW ENGLAND/NEW YORK STATE LATE IN THE WEEK THEN STALL ACROSS THE MID ATLANTIC. MODEL GUIDANCE SUGGESTS AT THIS POINT THAT THE FRONT WILL NOT ALTOGETHER TEMPER THE RISING TEMPS TIL POSSIBLY LATER IN THE WEEK...BUT INSTEAD WILL SERVE AS A BETTER SOURCE FOR THE INITIATION OF SHOWERS AND THUNDERSTORMS THROUGH THE PERIOD. THIS SHOULD LEAD TO MORE THAN JUST ISOLATED AFTN TSTMS ESP WITH THE LOW LEVEL MOISTURE/HIGH SFC DEWPOINTS THAT WILL BE IN PLACE...AND HAVE INCLUDED POPS FOR SCATTERED CONVECTION EACH DAY THROUGH NEXT WEEKEND. && .AVIATION /18Z MONDAY THROUGH SATURDAY/... STRONG SFC HEATING AND INCREASING MOISTURE WILL CONTRIBUTE TO DEVELOPING ADEQUATE INSTABILITY TO GENERATE SCATTERED SHOWERS AND THUNDERSTORMS...WITH THE FIRST OF DAY ALREADY AT JST. ACTIVITY WILL BE VERY HIT AND MISS...WITH TERMINALS REMAINING VFR EXCEPT WHERE THE CONVECTION MOVES IN...THEN CONDITIONS COULD BRIEFLY DROP TO IFR OR LOWER. SHOWERS AND STORMS WILL DIMINISH THIS EVENING...BUT AN INCREASINGLY HUMID AIRMASS WILL MAKE FOR SOME FOG/HAZE ISSUES OVERNIGHT WITH VISIBILITIES LIKELY TO DROP BACK INTO THE 2-4 MILE RANGE AT MOST TERMINALS. THESE REDUCED CONDITIONS WILL IMPROVE RAPIDLY AFTER SUNRISE TUESDAY...WITH ALL AIRPORTS GOING VFR BY MID MORNING AND STAYING THAT WAY UNTIL ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS BEGINS TO AFFECT THE AREA TUESDAY AFTERNOON AND EVENING. OUTLOOK... WED-SAT...VFR WITH AREAS OF MVFR AND SCATTERED SHOWERS/THUNDERSTORMS. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE NEAR TERM...LA CORTE SHORT TERM...LA CORTE LONG TERM...LAMBERT/GARTNER AVIATION...LA CORTE
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
350 PM EDT MON JUN 16 2014 .SYNOPSIS... DEEP LAYERED HIGH PRESSURE WILL PERSIST ATOP THE SOUTHEAST REGION THIS WEEK. THIS WILL KEEP A RELATIVELY WARM AIR MASS IN PLACE ACROSS THE AREA INTO THE WEEKEND. && .NEAR TERM /THROUGH TUESDAY/... AS OF 350 PM EDT MONDAY...INCREASED POPS ACROSS MUCH OF THE AREA THROUGH THE AFTERNOON IN RESPONSE TO SUBSTANTIAL INSTABILITY AND NO INHIBITION. RECENT RADAR IMAGERY INDICATES SCATTERED TO NUMEROUS PULSE THUNDERSTORMS AROUND THE REGION AS PEAK HEATING BUILDS. NUMEROUS OUTFLOWS FROM PREVIOUS CONVECTION COULD BE A FOCUS FOR NEW CELL GROWTH THROUGHOUT THE FORECAST AREA...THEREBY SUPPORTING THE ABOVE MENTIONED POP INCREASE. RAMPED POPS DOWN AS WITH PREVIOUS FORECAST AROUND/AFTER SUNSET ONCE HEATING IS LOST DUE TO THE PURELY THERMODYNAMIC NATURE OF THESE STORMS. OTHERWISE...TWEAKED TEMPERATURES AND DEWPOINTS TO REFLECT LATEST OBSERVATIONS AND LEFT THE REMAINDER OF THE FORECAST AS IS. PREVIOUS DISCUSSION... AS OF 200 PM...WELL AS ADVERTISED BY THE GSO/FFC SNDGS THIS MORNING...THERE IS NO INHIBITION...AND HENCE SCATTERED TO NUMEROUS SHWRS AND TSTMS HAVE BLOSSOMED QUICKLY ACRS THE CWFA...DESPITE LARGE HIGH PRES SYSTEM ATOP THE REGION. THE LAPS AND RAP BOTH SHOW 2500 TO OVER 4000 J/KG OF SBCAPE. SO I HAVE BUMPED UP POPS FURTHER FROM PREVIOUS UPDATE...WITH SOLID CHC TO LIKELY POP ACRS THE MTNS AND FOOTHILLS...AND CHC POP OVER PRETTY MUCH THE ENTIRE PIEDMONT. PWATS ARE 125-150% OF NORMAL AND STORMS ARE SLOW-MOVERS...SO ISOLD HEAVY RAIN/FLOOD THREAT LOOKS TO EXIST IN ADDITION TO A SMALL WET MICROBURST THREAT. LARGE HAIL LOOKS MORE UNLIKELY...BUT CANNOT BE RULED OUT GIVEN THE HIGH SBCAPE. STORMS SHUD DISSIPATE QUICKLY AFTER SUNSET...LEAVING SOME LINGER MID AND HIGH CLOUDINESS INTO THE LATE EVENING. WITH HIGH PRES STILL IN PLACE...WINDS SHUD BE LIGHT AND ALLOW FOR SOME PATCHY FOG...ESP IN THE MTN VLYS. LOW TEMPS WILL BE GENERALLY IN THE 60S MTNS AND UPR 60S TO LWR 70S PIEDMONT (ABOUT A CATEGORY ABOVE NORMAL). TUESDAY...LITTLE CHANGE IN THE ENVIRONMENT IS EXPECTED...WITH MODELS IN GOOD AGREEMENT ON 500 MB HIGH AROUND 592 DAM CENTERED JUST TO OUR WEST. PLENTY OF LLVL MOISTURE AND STRONG INSOLATION SHUD RESULT IN ANOTHER UNCAPPED...MOD-HIGHLY UNSTABLE DAY. SO EXPECT SCATTERED SHWRS AND TSTMS TO DEVELOP ACRS THE AREA...STARTING IN THE MTNS EARLY AFTN. A SMALL PULSE SEVERE THREAT WILL PROBABLY EXIST AGAIN...GIVEN SIMILAR PROFILES. HIGHS WILL BE A COUPLE CATEGORIES ABOVE NORMAL. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/... AS OF 200 PM MONDAY...NO SURPRISES WITH THE 12Z GUIDANCE IN THE SHORT TERM. AN UPPER RIDGE IS EXPECTED TO REMAIN FIRMLY IN PLACE OVER THE SOUTHEAST U.S. WITH THE WESTERN ATLANTIC SUBTROPICAL HIGH EXTENDING FROM BERMUDA TO THE COASTAL SOUTHEAST THROUGH THURSDAY. THAT MEANS WE CAN EXPECT THE TYPICAL DIURNALLY DRIVEN SHOWERS AND THUNDERSTORMS EACH AFTERNOON INTO THE EVENING HOURS. PORTIONS OF THE PIEDMONT COULD BE IN PLAY FOR AFTERNOON CONVECTION AS SOME OF THE MODELS ACTIVATE THE LEE TROUGH. HOWEVER...WOULD EXPECT THAT COVERAGE WOULD SHOULD BE ISOLATED IN NATURE DUE TO GENERAL SYNOPTIC SCALE SUBSIDENCE UNDER UPPER HIGH. HOWEVER...CONVECTIVE COVERAGE IN THE MOUNTAINS SHOULD BE SCT. HIGH TEMPERATURES WILL REMAIN HOT AND A COUPLE CATEGORIES ABOVE AVERAGE ON WED...AND 8-10 DEGEREES ABOVE AVE ON THU ACROSS THE PIEDMONT. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... AS OF 200 PM EDT MONDAY...STARTING 00Z FRI...THE 500MB RIDGE WILL CONTINUE TO BREAK DOWN OVER THE SE REGION THURSDAY NIGHT INTO FRIDAY. MEDIUM RANGE MODELS HAVE VORTICITY CENTERS PASSING MOSTLY TO OUR NORTH THROUGH THE WEEKEND. THIS COULD INDICATE THE NUMBER OF MCS OR MCC CROSSING THE EASTERN HALF OF THE NATION. ONE OF THESE VORT CENTERS CROSSES THE MID APPALACHIANS SATURDAY...BUT THE ECMWF HAS IT ARRIVING SATURDAY MORNING AND GFS HAS IT WASHING OUT AS IT ARRIVES LATE SATURDAY. THIS COULD BOOST THE COVERAGE OF SHOWERS AND STORMS ON SATURDAY...MAINLY FOR THE MTNS. A WEAK COLD FRONT WILL BE CROSSING TN AND KY ON MONDAY. MODELS SHOW A CLUSTER OF VORTS OVER THE LOWER MISS VALLEY EARLY NEXT WEEK POISED TO MOVE IN OUR DIRECTION. THE ECMWF AND GFS ARE QUITE DIFFERENT NEXT MONDAY WITH THE GFS HAVING A SIGNIFICANT 500MB TROUGH DIVING SE OVER MISS VALLEY AND EC HAVING A BROAD RIDGE OVER THE WHOLE NATION. CONVECTIVE ACTIVITY SHOULD BECOME MORE WIDESPREAD EARLY NEXT WEEK WITH CONTINUED VERY WARM TEMPS. IN TERMS OF INSTABILITY...GFS HAS GREATEST CAPE VALUES LATE SATURDAY OVER NE GA TO SW NC MTNS WITH AROUND 2500 AT THAT TIME. SEEMS MORE REASONABLE IN THE REST OF THE FORECAST. TEMPS A FEW DEGREES ABOVE NORMAL THROUGH THE PERIOD. && .AVIATION /20Z MONDAY THROUGH SATURDAY/... AT KCLT...SCATTERED TSTMS HAVE DEVELOPED ACRS MUCH OF WRN NC...WITH A SMALL CLUSTER OF STORMS ABOUT 20SM NW OF THE TERMINAL. THEY ARE WEAKENING AT THE TIME OF THE TAF ISSUANCE...BUT NEW CELLS MAY DEVELOP ALONG THE OUTFLOW. SO WILL GO WITH A 4-HR TEMPO FOR TSRA STARTING AT 19Z. CONVECTION SHUD QUICKLY WANE WITH LOSS OF DAYTIME HEATING THIS EVENING. WINDS SHUD BE LIGHT...EXCEPT IF ANY TSTMS GET CLOSE TO THE TERMINAL. WINDS ARE FAVORING A WSW DIRECTION. OTHERWISE...EXPECT VFR CONDITIONS. IF THERE IS A SOLID SHRA/TSRA HITS THE AIRFIELD...THERE MAY BE SOME FOG TOWARD DAYBREAK. WILL GO WITH VFR FOR NOW. ELSEWHERE...AS MENTIONED WITH KCLT...NUMEROUS STORMS DEVELOPING ACRS THE REGION. THEY ARE GENERALLY GARDEN VARIETY AND SLOW-MOVING. SO CONFIDENCE ON A DIRECT IMPACT IS STILL LOW. I WILL GO WITH VCTS AT ALL SITES FOR THE AFTN HOURS. THE STORMS SHUD DISSIPATE RAPIDLY WITH LOSS OF HEATING. DEBRIS CLOUDINESS WILL LINGER...BUT OVERALL SKIES SHUD CLEAR OUT...ALLOWING FOR PATCHY FOG DEVELOPMENT OVERNIGHT...ESP IN THE MTNS VLYS. WILL GO WITH MVFR AT KAVL FOR NOW...AND VFR AT THE OTHER SITES UNTIL WE SEE HOW MUCH RAIN FALLS IN THE AREA. OUTLOOK...ISOLATED TO SCATTERED AFTERNOON AND EVENING THUNDERSTORMS ARE EXPECTED THROUGH THE WEEK...WITH THE BEST COVERAGE ACROSS THE MTNS. THE BEST CHANCE FOR RESTRICTIONS WILL BE IN TSRA AND ALSO IN THE MTN VALLEYS EACH MORNING WHERE LOW CLOUDS AND FOG MAY FORM OVER AREAS OF RECENT RAINFALL. CONFIDENCE TABLE... 19-01Z 01-07Z 07-13Z 13-19Z KCLT HIGH 100% HIGH 100% HIGH 94% HIGH 100% KGSP HIGH 100% HIGH 100% HIGH 88% HIGH 100% KAVL HIGH 100% HIGH 97% HIGH 86% HIGH 100% KHKY HIGH 100% HIGH 100% HIGH 83% HIGH 100% KGMU HIGH 100% HIGH 100% HIGH 94% HIGH 100% KAND HIGH 100% HIGH 100% HIGH 86% HIGH 100% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...DEO NEAR TERM...ARK/CDG SHORT TERM...LG LONG TERM...DEO AVIATION...ARK
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
227 PM EDT MON JUN 16 2014 .SYNOPSIS... DEEP LAYERED HIGH PRESSURE WILL PERSIST ATOP THE SOUTHEAST REGION THIS WEEK. THIS WILL KEEP A RELATIVELY WARM AIR MASS IN PLACE ACROSS THE AREA INTO THE WEEKEND. && .NEAR TERM /THROUGH TUESDAY/... AS OF 200 PM...WELL AS ADVERTISED BY THE GSO/FFC SNDGS THIS MORNING...THERE IS NO INHIBITION...AND HENCE SCATTERED TO NUMEROUS SHWRS AND TSTMS HAVE BLOSSOMED QUICKLY ACRS THE CWFA...DESPITE LARGE HIGH PRES SYSTEM ATOP THE REGION. THE LAPS AND RAP BOTH SHOW 2500 TO OVER 4000 J/KG OF SBCAPE. SO I HAVE BUMPED UP POPS FURTHER FROM PREVIOUS UPDATE...WITH SOLID CHC TO LIKELY POP ACRS THE MTNS AND FOOTHILLS...AND CHC POP OVER PRETTY MUCH THE ENTIRE PIEDMONT. PWATS ARE 125-150% OF NORMAL AND STORMS ARE SLOW-MOVERS...SO ISOLD HEAVY RAIN/FLOOD THREAT LOOKS TO EXIST IN ADDITION TO A SMALL WET MICROBURST THREAT. LARGE HAIL LOOKS MORE UNLIKELY...BUT CANNOT BE RULED OUT GIVEN THE HIGH SBCAPE. STORMS SHUD DISSIPATE QUICKLY AFTER SUNSET...LEAVING SOME LINGER MID AND HIGH CLOUDINESS INTO THE LATE EVENING. WITH HIGH PRES STILL IN PLACE...WINDS SHUD BE LIGHT AND ALLOW FOR SOME PATCHY FOG...ESP IN THE MTN VLYS. LOW TEMPS WILL BE GENERALLY IN THE 60S MTNS AND UPR 60S TO LWR 70S PIEDMONT (ABOUT A CATEGORY ABOVE NORMAL). TUESDAY...LITTLE CHANGE IN THE ENVIRONMENT IS EXPECTED...WITH MODELS IN GOOD AGREEMENT ON 500 MB HIGH AROUND 592 DAM CENTERED JUST TO OUR WEST. PLENTY OF LLVL MOISTURE AND STRONG INSOLATION SHUD RESULT IN ANOTHER UNCAPPED...MOD-HIGHLY UNSTABLE DAY. SO EXPECT SCATTERED SHWRS AND TSTMS TO DEVELOP ACRS THE AREA...STARTING IN THE MTNS EARLY AFTN. A SMALL PULSE SEVERE THREAT WILL PROBABLY EXIST AGAIN...GIVEN SIMILAR PROFILES. HIGHS WILL BE A COUPLE CATEGORIES ABOVE NORMAL. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/... AS OF 200 PM MONDAY...NO SURPRISES WITH THE 12Z GUIDANCE IN THE SHORT TERM. AN UPPER RIDGE IS EXPECTED TO REMAIN FIRMLY IN PLACE OVER THE SOUTHEAST U.S. WITH THE WESTERN ATLANTIC SUBTROPICAL HIGH EXTENDING FROM BERMUDA TO THE COASTAL SOUTHEAST THROUGH THURSDAY. THAT MEANS WE CAN EXPECT THE TYPICAL DIURNALLY DRIVEN SHOWERS AND THUNDERSTORMS EACH AFTERNOON INTO THE EVENING HOURS. PORTIONS OF THE PIEDMONT COULD BE IN PLAY FOR AFTERNOON CONVECTION AS SOME OF THE MODELS ACTIVATE THE LEE TROUGH. HOWEVER...WOULD EXPECT THAT COVERAGE WOULD SHOULD BE ISOLATED IN NATURE DUE TO GENERAL SYNOPTIC SCALE SUBSIDENCE UNDER UPPER HIGH. HOWEVER...CONVECTIVE COVERAGE IN THE MOUNTAINS SHOULD BE SCT. HIGH TEMPERATURES WILL REMAIN HOT AND A COUPLE CATEGORIES ABOVE AVERAGE ON WED...AND 8-10 DEGEREES ABOVE AVE ON THU ACROSS THE PIEDMONT. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... AS OF 200 PM EDT MONDAY...STARTING 00Z FRI...THE 500MB RIDGE WILL CONTINUE TO BREAK DOWN OVER THE SE REGION THURSDAY NIGHT INTO FRIDAY. MEDIUM RANGE MODELS HAVE VORTICITY CENTERS PASSING MOSTLY TO OUR NORTH THROUGH THE WEEKEND. THIS COULD INDICATE THE NUMBER OF MCS OR MCC CROSSING THE EASTERN HALF OF THE NATION. ONE OF THESE VORT CENTERS CROSSES THE MID APPALACHIANS SATURDAY...BUT THE ECMWF HAS IT ARRIVING SATURDAY MORNING AND GFS HAS IT WASHING OUT AS IT ARRIVES LATE SATURDAY. THIS COULD BOOST THE COVERAGE OF SHOWERS AND STORMS ON SATURDAY...MAINLY FOR THE MTNS. A WEAK COLD FRONT WILL BE CROSSING TN AND KY ON MONDAY. MODELS SHOW A CLUSTER OF VORTS OVER THE LOWER MISS VALLEY EARLY NEXT WEEK POISED TO MOVE IN OUR DIRECTION. THE ECMWF AND GFS ARE QUITE DIFFERENT NEXT MONDAY WITH THE GFS HAVING A SIGNIFICANT 500MB TROUGH DIVING SE OVER MISS VALLEY AND EC HAVING A BROAD RIDGE OVER THE WHOLE NATION. CONVECTIVE ACTIVITY SHOULD BECOME MORE WIDESPREAD EARLY NEXT WEEK WITH CONTINUED VERY WARM TEMPS. IN TERMS OF INSTABILITY...GFS HAS GREATEST CAPE VALUES LATE SATURDAY OVER NE GA TO SW NC MTNS WITH AROUND 2500 AT THAT TIME. SEEMS MORE REASONABLE IN THE REST OF THE FORECAST. TEMPS A FEW DEGREES ABOVE NORMAL THROUGH THE PERIOD. && .AVIATION /19Z MONDAY THROUGH SATURDAY/... AT KCLT...SCATTERED TSTMS HAVE DEVELOPED ACRS MUCH OF WRN NC...WITH A SMALL CLUSTER OF STORMS ABOUT 20SM NW OF THE TERMINAL. THEY ARE WEAKENING AT THE TIME OF THE TAF ISSUANCE...BUT NEW CELLS MAY DEVELOP ALONG THE OUTFLOW. SO WILL GO WITH A 4-HR TEMPO FOR TSRA STARTING AT 19Z. CONVECTION SHUD QUICKLY WANE WITH LOSS OF DAYTIME HEATING THIS EVENING. WINDS SHUD BE LIGHT...EXCEPT IF ANY TSTMS GET CLOSE TO THE TERMINAL. WINDS ARE FAVORING A WSW DIRECTION. OTHERWISE...EXPECT VFR CONDITIONS. IF THERE IS A SOLID SHRA/TSRA HITS THE AIRFIELD...THERE MAY BE SOME FOG TOWARD DAYBREAK. WILL GO WITH VFR FOR NOW. ELSEWHERE...AS MENTIONED WITH KCLT...NUMEROUS STORMS DEVELOPING ACRS THE REGION. THEY ARE GENERALLY GARDEN VARIETY AND SLOW-MOVING. SO CONFIDENCE ON A DIRECT IMPACT IS STILL LOW. I WILL GO WITH VCTS AT ALL SITES FOR THE AFTN HOURS. THE STORMS SHUD DISSIPATE RAPIDLY WITH LOSS OF HEATING. DEBRIS CLOUDINESS WILL LINGER...BUT OVERALL SKIES SHUD CLEAR OUT...ALLOWING FOR PATCHY FOG DEVELOPMENT OVERNIGHT...ESP IN THE MTNS VLYS. WILL GO WITH MVFR AT KAVL FOR NOW...AND VFR AT THE OTHER SITES UNTIL WE SEE HOW MUCH RAIN FALLS IN THE AREA. OUTLOOK...ISOLATED TO SCATTERED AFTERNOON AND EVENING THUNDERSTORMS ARE EXPECTED THROUGH THE WEEK...WITH THE BEST COVERAGE ACROSS THE MTNS. THE BEST CHANCE FOR RESTRICTIONS WILL BE IN TSRA AND ALSO IN THE MTN VALLEYS EACH MORNING WHERE LOW CLOUDS AND FOG MAY FORM OVER AREAS OF RECENT RAINFALL. CONFIDENCE TABLE... 18-24Z 00-06Z 06-12Z 12-18Z KCLT HIGH 100% HIGH 100% HIGH 94% HIGH 100% KGSP HIGH 100% HIGH 100% HIGH 88% HIGH 100% KAVL HIGH 100% HIGH 100% HIGH 83% HIGH 100% KHKY HIGH 100% HIGH 100% HIGH 83% HIGH 100% KGMU HIGH 100% HIGH 100% HIGH 94% HIGH 100% KAND HIGH 100% HIGH 100% HIGH 86% HIGH 100% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...DEO NEAR TERM...ARK SHORT TERM...LG LONG TERM...DEO AVIATION...ARK
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1109 AM EDT MON JUN 16 2014 .SYNOPSIS... DEEP LAYERED HIGH PRESSURE WILL PERSIST ATOP THE SOUTHEAST REGION THIS WEEK. THIS WILL KEEP A RELATIVELY WARM AIR MASS IN PLACE ACROSS THE AREA INTO THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1045 AM...A LARGE PATCH OF ALTOCU CAN BE SEEN IN METARS AND ON VIS SAT IMAGERY...DISSIPATING UNDER A LARGE ANTICYCLONE CENTERED ATOP THE CWFA THIS MORNING. THE CLOUDS ARE INDICATIVE OF PLENTY OF MOISTURE FOR CONVECTION TODAY. DESPITE A FAIRLY SUPPRESSIVE SYNOPTIC SETUP...GUIDANCE SEEMS TO BE IN DECENT AGREEMENT ON SCATTERED SHWRS AND TSTMS DEVELOPING THIS AFTN. I BLENDED IN THE CONVECTION-ALLOWING MODEL CONSENSUS AND SMOOTHED IT OUT...RESULTING IN HIGH-CHC TO EVEN SOME LIKELY POP IN THE NC MTNS...AND GENERALLY LOW-END CHC TO SLGT CHC ACRS THE PIEDMONT. THE 12Z GSO AND FFC SOUNDINGS SHOW 2500+ J/KG OF CAPE WITH NO CIN BY PEAK HEATING. THERE IS ALSO SOME DRY AIR ABOVE 700 MB ON THE GSO SNDG...BUT MID LVL MOISTURE LOOKS TO PIVOT IN FROM THE SOUTHWEST. SO DCAPE MAY ONLY BE MODEST THIS AFTN...BUT STILL ENUF FOR A WET MICROBURST THREAT. THE LATEST DAY 1 SPC CONVECTIVE OUTLOOK HAS A 5% FOR DAMAGING WIND THREAT FOR MOST OF THE CWFA. AS FOR ANYTHING OTHER THAN PULSE CONVECTIVE MODE...THE SHEAR LOOKS FAIRLY WEAK. THE LAST COUPLE OF HRRR RUNS HINT AT A COLD POOL ORGANIZING OFF THE BLUE RIDGE...DRIFTING TOWARD THE CHARLOTTE METRO AREA. THIS MAY HELP ENHANCE COVERAGE THERE. ABOVE NORMAL AFTN HIGHS ARE EXPECTED. DEEP CONVECTION SHOULD ASH OUT ONE TO TWO HOURS FOLLOWING SUNSET THIS EVENING. CONDENSATION PRESSURE DEFICITS INDICATE LESS POTENTIAL FOR FOG TONIGHT...BUT FOG IS POSSIBLE OVER AREAS OF AFTERNOON RAINFALL. TEMPERATURES THROUGH THE NEAR TERM SHOULD RANGE A FEW DEGREES ABOVE NORMAL. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 230 AM MONDAY...THE FORECAST LOOKS VERY PERSISTENT AS AN UPPER RIDGE REMAINS FIRMLY IN PLACE OVER THE SOUTHEAST AND SURFACE HIGH PRESSURE EXTENDS FROM BERMUDA TO THE COASTAL SOUTHEAST THROUGH WEDNESDAY AND BEYOND. THAT MEANS WE CAN EXPECT TYPICAL DIURNALLY DRIVEN SHOWERS AND THUNDERSTORMS EACH DAY. HIGH TEMPERATURES SHOULD CREEP UP A DEGREE OR SO TUESDAY AND WEDNESDAY...AND LOW TEMPS SHOULD BE SEASONALLY MILD. && .LONG TERM /THURSDAY THROUGH SUNDAY/... AS OF 245 AM EDT MONDAY...SUMMER...SUMMER...SUMMER...OR SO IT WILL FEEL LIKE THROUGH THE MEDIUM RANGE. THE UPPER RIDGE OVER THE SOUTHEAST AND CAROLINAS WILL SLOWLY BREAK DOWN AND FLATTEN AT THE END OF THE WEEK. THE MODELS SHOW A STEADY PARADE OF VORTICITY CENTERS MOVING PAST OVER THE TOP OF THE FLATTENING RIDGE...EACH OF WHICH COULD BE ASSOCIATED WITH AN MCS OR REMNANTS THEREOF...BUT ALAS ALL THESE FEATURES ARE EXPECTED TO REMAIN NORTH OF THE FCST AREA THURSDAY AND FRIDAY. THE TREND IN THE NEW MODEL GUIDANCE FOR THE WEEKEND IS TO NOT BRING ANY SIGNIFICANT SHORT WAVES ACROSS THE REGION...WHICH SUGGESTS LESS OF A CHANCE OF ORGANIZED THUNDERSTORM ACTIVITY FOR SATURDAY AND SUNDAY. HOWEVER...THE FCST WAS UPDATED TO RAISE THE POP INTO THE CHANCE RANGE BASED ON SLIGHTLY BETTER COVERAGE IN THE MODEL GUIDANCE AND TO COME MORE INTO LINE WITH NEIGHBORING FCSTS. && .AVIATION /15Z MONDAY THROUGH FRIDAY/... AT KCLT...VFR CONDITIONS IS GENERALLY EXPECTED DURING THE TAF PERIOD. HOWEVER...MVFR FOG/HZ COULD LINGER ACROSS THE TERMINAL UNTIL 13Z. LIGHT SOUTH WINDS THIS MORNING WILL VEER TO WEST-SOUTHWEST THIS AFTERNOON. THE NAM INDICATES THAT DEEP CONVECTION COULD DEVELOP OVER THE EAST FACING SLOPES AROUND MID DAY...TRACKING EAST WITH A COLD POOL DURING THE AFTERNOON HOURS. AT THIS TIME...THE POTENTIAL FOR CONVECTION APPEARS LIMITED TO THE 22Z TO 01Z TIME WINDOW ACROSS THE I-77 CORRIDOR. ELSEWHERE...AT 1030Z...KGSP RADAR DETECTED A FEW LIGHT SHRA ACROSS THE WESTERN NC MTNS. THESE SHRAS APPEAR SUPPORTED BY WEAK INSTABILITY AND LLVL SOUTH FLOW. IN THE NEAR TERM...THE SHRA SHOULD NOT IMPACT THE WESTERN CAROLINA TERMINALS. MID LEVEL CLOUD COVER WILL LIKELY LINGER THROUGH THE MORNING. BASED ON RECENT MORNING OBS...FOG OR HAZE MAY TEMPO IMPACT TERMINALS UNTIL 13Z. THE NAM INDICATES THAT DEEP CONVECTION COULD DEVELOP OVER THE EAST FACING SLOPES AROUND MID DAY...TRACKING EAST WITH A COLD POOL DURING THE AFTERNOON HOURS. THE POTENTIAL FOR CONVECTION WARRANTS A PROB30 WITHIN THE 19Z TO 24Z WINDOW AT KAVL AND KHKY. OUTLOOK...ISOLATED TO SCATTERED AFTERNOON AND EVENING THUNDERSTORMS ARE EXPECTED THROUGH THE WEEK...WITH THE BEST COVERAGE ACROSS THE MTNS. THE BEST CHANCE FOR RESTRICTIONS WILL BE IN TSRA AND ALSO IN THE MTN VALLEYS EACH MORNING WHERE LOW CLOUDS AND FOG MAY FORM OVER AREAS OF RECENT RAINFALL. CONFIDENCE TABLE... 15-21Z 21-03Z 03-09Z 09-15Z KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100% KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAVL HIGH 100% HIGH 100% HIGH 100% HIGH 100% KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100% KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...PM NEAR TERM...ARK/NED SHORT TERM...PM LONG TERM...PM AVIATION...NED
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
623 AM CDT MON JUN 16 2014 .DISCUSSION... SEE THE 12Z AVIATION DISCUSSION BELOW. 40 && .AVIATION... ISOLATED SHOWERS WERE DEVELOPING OFFSHORE AND MOVING INTO THE COASTAL AREAS. THESE ARE EXPECTED TO AFFECT MAINLY THE KGLS AREA THROUGH MID MORNING. OTHERWISE...MVFR CONDITIONS OVER THE KCLL... KUTS...AND KCXO SITES ARE EXPECTED TO LIFT BY AROUND 14Z. VFR IS EXPECTED ELSEWHERE. A REPEAT IS LIKELY TONIGHT...WITH MVFR DEVELOPING AFTER 06Z IN THE NORTH WITH ISOLATED SHOWERS NEAR THE COAST. 40 && .PREV DISCUSSION... /ISSUED 339 AM CDT MON JUN 16 2014/ DISCUSSION... AT 07Z...LOW PRESSURE WAS OVER EASTERN NEW MEXICO WITH HIGH PRESSURE OVER THE SE U.S.. THE PRESSURE GRADIENT WAS TIGHTER THAN THE PAST FEW NIGHTS AND WIND SPEEDS WERE A BIT HIGHER. CLOUD COVER IS ALSO MORE PREVALENT AND TEMPS ARE WARMER. AT 850 MB...THE DEEPEST MOISTURE EXTENDED FROM NORTH CENTRAL TEXAS TO WESTERN MISSOURI. 850 TEMPS WERE BETWEEN 18-20 C. A WEAK TROUGH AXIS EXTENDED ACROSS EASTERN NEW MEXICO. AT 500 MB...A WEAK TROUGH AXIS EXTENDED FROM A WEAK S/WV OVER SOUTH CENTRAL OKLAHOMA TO ABOUT LAREDO. AT 250 MB...WINDS DID NOT SHOW THE SPLITTING STRUCTURE AS ADVERTISED YESTERDAY. THE GFS AND NAM STILL CONT TO SHOW A SPLITTING JET DEVELOPING LATER TODAY WHILE THE ECMWF MAINTAINS A ZONAL FLOW. FCST SOUNDINGS SHOW PW VALUES BETWEEN 1.5-1.6 INCHES AND CONVECTIVE TEMPS IN THE UPPER 80S. A SUBTLE CAP WAS NOTED AROUND 700 MB AND THE SOUNDING WAS VERY DRY ABOVE 700 MB. THINK SOME ADDITIONAL LIFT WILL BE POSSIBLE TODAY ON THE EAST SIDE OF THE WEAK 500 MB TROUGH AXIS. STILL CONCERNED THAT THE DRIER AIR ALOFT WILL LIMIT RAIN CHANCES TODAY. THE RAP13 AND HRRR ARE BOTH MORE AGGRESSIVE WITH RAIN CHANCES TODAY BUT NOT CONFIDENT ENOUGH TO RAISE POPS. WILL KEEP 20 POPS IN PLACE TODAY. ON TUESDAY...THE NAM IS MUCH MORE AGGRESSIVE WITH PW VALUES INCREASING TO 1.9 INCHES. CONVECTIVE TEMPS REMAIN IN THE UPPER 80S WITH DRY AIR AGAIN NOTED IN THE SOUNDING. THE GFS AND NAM BRING A WEAK DISTURBANCE ACROSS THE REGION DURING THE AFTERNOON BUT AGAIN WITH DRY AIR ABOVE 700 MB...CAN`T GO MUCH HIGHER THAN 20 POPS FOR NOW. PWATS REMAIN AROUND 1.80 INCHES ON WED WITH WEAK CAPPING NOTED AT 700 MB AND SIGNIFICANT DRYING AT 600 MB AND ABOVE. WILL AGAIN JUST CARRY 20 POPS. THE GFS AND ECMWF ARE NOT AS AGGRESSIVE WITH THE UPPER RIDGE BUILDING BACK INTO TEXAS ON THURSDAY-SUNDAY. 850 TEMPS STILL WARM FROM 16 C TO 19 C BUT 500 HEIGHTS SHOW ONLY A MINOR INCREASE. WILL CONTINUE WITH THE DRY FCST AND SUBTLE WARMING TREND. 43 MARINE... NOT MUCH CHANGE IN THE MARINE CONDITIONS THIS WEEK. CAUTION CONDITIONS ARE LIKELY DURING THE NIGHTTIME AND EARLY MORNING PERIODS THROUGH THE MID WEEK PERIOD...ESPECIALLY OVER THE OFFSHORE WATERS. ISOLATED SHOWERS AND A POSSIBLE THUNDERSTORM SHOULD PERSIST AS WELL THROUGH MID WEEK...ESPECIALLY DURING THE OVERNIGHT AND EARLY MORNING PERIODS. 40 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 93 76 92 75 91 / 20 10 20 10 20 HOUSTON (IAH) 93 78 91 78 91 / 20 10 20 10 20 GALVESTON (GLS) 89 80 88 80 88 / 20 20 20 20 20 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 9 AM CDT THIS MORNING FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM. && $$ DISCUSSION...43 AVIATION/MARINE...40
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
339 AM CDT MON JUN 16 2014 .DISCUSSION... AT 07Z...LOW PRESSURE WAS OVER EASTERN NEW MEXICO WITH HIGH PRESSURE OVER THE SE U.S.. THE PRESSURE GRADIENT WAS TIGHTER THAN THE PAST FEW NIGHTS AND WIND SPEEDS WERE A BIT HIGHER. CLOUD COVER IS ALSO MORE PREVALENT AND TEMPS ARE WARMER. AT 850 MB...THE DEEPEST MOISTURE EXTENDED FROM NORTH CENTRAL TEXAS TO WESTERN MISSOURI. 850 TEMPS WERE BETWEEN 18-20 C. A WEAK TROUGH AXIS EXTENDED ACROSS EASTERN NEW MEXICO. AT 500 MB...A WEAK TROUGH AXIS EXTENDED FROM A WEAK S/WV OVER SOUTH CENTRAL OKLAHOMA TO ABOUT LAREDO. AT 250 MB...WINDS DID NOT SHOW THE SPLITTING STRUCTURE AS ADVERTISED YESTERDAY. THE GFS AND NAM STILL CONT TO SHOW A SPLITTING JET DEVELOPING LATER TODAY WHILE THE ECMWF MAINTAINS A ZONAL FLOW. FCST SOUNDINGS SHOW PW VALUES BETWEEN 1.5-1.6 INCHES AND CONVECTIVE TEMPS IN THE UPPER 80S. A SUBTLE CAP WAS NOTED AROUND 700 MB AND THE SOUNDING WAS VERY DRY ABOVE 700 MB. THINK SOME ADDITIONAL LIFT WILL BE POSSIBLE TODAY ON THE EAST SIDE OF THE WEAK 500 MB TROUGH AXIS. STILL CONCERNED THAT THE DRIER AIR ALOFT WILL LIMIT RAIN CHANCES TODAY. THE RAP13 AND HRRR ARE BOTH MORE AGGRESSIVE WITH RAIN CHANCES TODAY BUT NOT CONFIDENT ENOUGH TO RAISE POPS. WILL KEEP 20 POPS IN PLACE TODAY. ON TUESDAY...THE NAM IS MUCH MORE AGGRESSIVE WITH PW VALUES INCREASING TO 1.9 INCHES. CONVECTIVE TEMPS REMAIN IN THE UPPER 80S WITH DRY AIR AGAIN NOTED IN THE SOUNDING. THE GFS AND NAM BRING A WEAK DISTURBANCE ACROSS THE REGION DURING THE AFTERNOON BUT AGAIN WITH DRY AIR ABOVE 700 MB...CAN`T GO MUCH HIGHER THAN 20 POPS FOR NOW. PWATS REMAIN AROUND 1.80 INCHES ON WED WITH WEAK CAPPING NOTED AT 700 MB AND SIGNIFICANT DRYING AT 600 MB AND ABOVE. WILL AGAIN JUST CARRY 20 POPS. THE GFS AND ECMWF ARE NOT AS AGGRESSIVE WITH THE UPPER RIDGE BUILDING BACK INTO TEXAS ON THURSDAY-SUNDAY. 850 TEMPS STILL WARM FROM 16 C TO 19 C BUT 500 HEIGHTS SHOW ONLY A MINOR INCREASE. WILL CONTINUE WITH THE DRY FCST AND SUBTLE WARMING TREND. 43 && .MARINE... NOT MUCH CHANGE IN THE MARINE CONDITIONS THIS WEEK. CAUTION CONDITIONS ARE LIKELY DURING THE NIGHTTIME AND EARLY MORNING PERIODS THROUGH THE MID WEEK PERIOD...ESPECIALLY OVER THE OFFSHORE WATERS. ISOLATED SHOWERS AND A POSSIBLE THUNDERSTORM SHOULD PERSIST AS WELL THROUGH MID WEEK...ESPECIALLY DURING THE OVERNIGHT AND EARLY MORNING PERIODS. 40 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 93 76 92 75 91 / 20 10 20 10 20 HOUSTON (IAH) 93 78 91 78 91 / 20 10 20 10 20 GALVESTON (GLS) 89 80 88 80 88 / 20 20 20 20 20 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 9 AM CDT THIS MORNING FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
1113 PM CDT SUN JUN 15 2014 .AVIATION... MVFR CEILINGS...WITH CEILINGS AROUND 1500 FEET...WILL SPREAD NORTH IN THE WACO AREA AROUND 08Z AND INTO THE METROPLEX AROUND 08Z. THE CEILINGS WILL IMPROVE TO VFR LATE MORNING /15-17Z/. SOUTH WINDS AROUND 15 KNOTS WILL PREVAIL WITH GUSTS AROUND 25 KNOTS EXPECTED 17Z MONDAY THROUGH 01Z TUESDAY. LOW CLOUDS WILL SPREAD BACK NORTH ONCE AGAIN LATE MONDAY NIGHT /AFTER 08Z TUESDAY/. 58 && .UPDATE... SATELLITE AND RADAR SHOW HIGH CLOUDS FROM THE THUNDERSTORMS THAT FORMED BETWEEN ANDREWS...SWEETWATER AND OZONA ARE SPREADING EAST INTO NORTH TEXAS THIS EVENING. THE WINDOW HAS CLOSED FOR THE POSSIBILITY OF ISOLATED THUNDERSTORMS ACROSS THE WEST PART OF THE FORECAST AREA THIS EVENING. THE ONLY CHANGES MADE WERE TO REMOVE THE SLIGHT CHANCE OF THUNDERSTORMS FROM THIS EVENINGS FORECAST AND TO ADJUST THE HOURLY GRIDS. UPDATES HAVE BEEN SENT. 58 && .PREV DISCUSSION... /ISSUED 324 PM CDT SUN JUN 15 2014/ AN 18Z AIRCRAFT SOUNDING FROM DALLAS LOVE FIELD OBSERVED A SUBSTANTIAL CAP IN PLACE OVER NORTH TEXAS...DESPITE TEMPERATURES IN THE LOWER 90S WITH DEW POINTS HOVERING AROUND 70 DEGREES. OBSERVED SURFACE BASED CAPE WAS JUST OVER 1000 J/KG ON THIS RAOB AND THE CONVECTIVE INHIBITION WAS AROUND 150 J/KG. VISIBLE SATELLITE IMAGERY SHOWED A STRATOCUMULUS FIELD IN PLACE ACROSS MUCH OF NORTH AND CENTRAL TEXAS WITH VERY LITTLE VERTICAL DEVELOPMENT. LOOPING THROUGH THE VISIBLE SATELLITE IMAGERY...SUBTLE WAVES WERE EVIDENT IN THIS STRATOCUMULUS FIELD...INDICATIVE OF A STABLE LAYER JUST ABOVE THE CLOUD LEVEL (LCL). TAKING THIS INTO ACCOUNT...THINK THAT OBSERVATIONAL EVIDENCE IS POINTING TO THE DALLAS LOVE FIELD SOUNDING BEING FAIRLY REPRESENTATIVE OF THE THERMODYNAMIC ENVIRONMENT IN PLACE OVER MOST OF THE CWA THIS AFTERNOON. AN EARLY AFTERNOON SURFACE ANALYSIS AND WATER VAPOR SATELLITE IMAGERY ALSO SUGGEST NO SIGNIFICANT MECHANISMS IN THE CWA TO PROVIDE FORCING FOR ASCENT. AS A RESULT...THINK THAT THE CHANCES OF THUNDERSTORMS DEVELOPING WITHIN THE CWA THIS AFTERNOON ARE VERY SMALL. 19Z VISIBLE SATELLITE IMAGERY DOES SHOW A MORE ORGANIZED CUMULUS FIELD DEVELOPING TO THE WEST OF THE CWA...IN AN AXIS OF GREATER INSTABILITY PER LOCALLY CALCULATED CONVECTIVE PARAMETERS AND SPC`S SFCOA. WHILE THERE WAS LITTLE VERTICAL DEVELOPMENT OBSERVED IN THIS CU FIELD AT THE TIME OF THIS DISCUSSION...THE CONGESTED AND LINEAR APPEARANCE OF THE CLOUDS SUGGESTS A LOCAL DEEPENING OF THE LOW-LEVEL MOIST LAYER ALONG A SURFACE TROUGH/CONVERGENCE LINE LOCATED FROM VERNON SOUTH TO JUST EAST OF SWEETWATER. THE 17Z HRRR MODEL REALLY PICKS UP ON THIS LOW-LEVEL CONVERGENCE ZONE AND INITIATES POCKETS OF THUNDERSTORMS ALONG THIS LINE BY 22Z...OR LATE THIS AFTERNOON. ASSUMING THIS PANS OUT...STORMS WILL INITIATE TO THE WEST OF THE CWA...HOWEVER WINDS ALOFT WOULD TEND TO STEER THESE STORMS EAST. WINDS ALOFT AND DEEP LAYER SHEAR ARE FAIRLY WEAK...SO ANY EASTWARD STORM MOTION WOULD TEND TO BE SLOW...ON THE ORDER OF 15 MPH OR SO. EVEN IF STORMS DEVELOP AS THE HRRR SUGGESTS...THERE IS NO GUARANTEE THAT THEY WILL ACTUALLY BE ABLE TO MOVE EAST INTO OUR WESTERN CWA THIS EVENING. STORM MOTION IS DEPENDENT NOT JUST UPON STEERING WINDS ALOFT...BUT IS ALSO DEPENDENT UPON THE DIRECTION THAT NEW UPDRAFTS TEND TO DEVELOP ON. THIS IS REFERRED TO AS UPDRAFT PROPAGATION...OR SIMPLY PROPAGATION. THE DIRECTION OF NEW UPDRAFT DEVELOPMENT IS USUALLY LOCATED ON THE SIDE OF THE STORM THAT THE LOW-LEVEL WIND FIELD IS POINTING TOWARDS. THAT IS...IF YOU HAVE SOUTHERLY WINDS IN THE LOWER ATMOSPHERE...NEW UPDRAFTS WILL TEND TO BE ON THE SOUTH SIDE OF AN EXISTING STORM. THE LATEST SPC SFCOA INDICATED 850 MB WINDS OUT OF THE SOUTH AT 15 KTS...WHICH SHOULD DIRECT NEW UPDRAFTS...AND THE PROPAGATION OF ANY STORMS THAT DEVELOP...TO THE SOUTH. WITH THE MAGNITUDE OF THE LOW-LEVEL WINDS JUST ABOUT EQUAL TO THE PROJECTED STORM MOTION FROM STEERING WINDS ALONE...STORMS WILL TEND TO BUILD SOUTH OR SOUTHEAST INSTEAD OF DRIFTING EAST WITH THE STEERING WINDS ALOFT. BECAUSE OF THIS...THINK THAT THE CHANCES OF MULTIPLE STORMS MOVING INTO THE WESTERN CWA THIS EVENING ARE SMALL. HOWEVER...CANNOT RULE OUT A STORM OR TWO MEANDERING OVER LOCATIONS WEST OF A LINE FROM BOWIE TO MINERAL WELLS TO GOLDTHWAITE THROUGH MIDNIGHT TONIGHT. STORMS WILL KEEP RUNNING INTO THE CAP IN PLACE OVER NORTH AND CENTRAL TEXAS IF THEY MOVE EAST...SO THEY SHOULD WEAKEN AND EVENTUALLY DISSIPATE IF THEY EVER MANAGE TO MOVE OFF THE SURFACE TROUGH TO OUR WEST. STRONG WIND GUSTS AND CLOUD TO GROUND LIGHTNING ARE THE ONLY EXPECTED HAZARDS FROM STORMS THIS EVENING. MONDAY AND TUESDAY...UPPER LEVEL RIDGING IS EXPECTED TO BUILD OVER THE SOUTHEASTERN CONUS...EXTENDING OVER NORTH AND CENTRAL TEXAS BY TOMORROW MORNING. AT THE SAME TIME...A STRONG UPPER TROUGH IS EXPECTED TO BUILD OVER THE NORTHWESTERN CONUS...LEAVING SOUTHWEST FLOW ALOFT OVER THE SOUTHERN HIGH PLAINS. WHILE NOT OVERLY STRONG...THE RIDGE ALOFT WILL BE THE DOMINANT LARGE SCALE FEATURE OVER NORTH TEXAS THROUGH TUESDAY. AS A RESULT...MOST LOCATIONS WILL REMAIN DRY THROUGH WEDNESDAY MORNING WITH HIGHS TOPPING OUT IN THE LOWER 90S EACH DAY. WITH SOUTHWEST FLOW ALOFT OVER THE SOUTHERN HIGH PLAINS...LEE SIDE TROUGHING WILL KEEP SOUTHERLY FLOW IN THE LOWER ATMOSPHERE OVER THE CWA. PERSISTENT SOUTHERLY WINDS MAY BE STRONG ENOUGH TO SEND THE GULF COAST SEA-BREEZE BOUNDARY NORTH INTO CENTRAL TEXAS BY TUESDAY AFTERNOON. IF THIS OCCURS...ISOLATED THUNDERSTORMS ARE POSSIBLE ACROSS CENTRAL TEXAS THROUGH SUNSET. LEFT LOW POPS IN THE FORECAST FOR THIS POSSIBILITY ON TUESDAY AFTERNOON. WEDNESDAY...THE ECMWF CONTINUES TO ADVERTISE AN UPPER LOW MOVING FROM NORTHERN MEXICO OUT OVER THE CWA WEDNESDAY AFTERNOON IN THE SOUTHWEST FLOW ALOFT. THE NAM IS ON BOARD WITH THIS SOLUTION WITH THE CANADIAN AND GFS HARDLY SHOWING ANY DISTURBANCE ALOFT AT ALL. CONTINUE TO SIDE WITH THE ECMWF/NAM SOLUTION AT THIS TIME AS THIS HAS BEEN THE CONSISTENT SOLUTION FOR THE PAST 3-4 DAYS WHILE THE GFS AND CANADIAN HAVE BEEN WAFFLING ON THE EXISTENCE OF THIS UPPER LEVEL DISTURBANCE. CONSISTENCY DOES NOT EQUAL ACCURACY...BUT WHEN DEALING WITH FORECAST MODELS AND DIFFERENCES IN DATA ASSIMILATION AND MODEL INITIALIZATION...CONSISTENCY IS OFTEN A GOOD SIGN THAT A MODEL HAS LOCKED ONTO SOMETHING OTHER MODELS ARE MISSING. DID NOT RAISE POPS ABOVE 20 PERCENT AT THIS TIME AS IT WOULD BE NICE TO SEE OBSERVATIONAL EVIDENCE OF THIS UPPER LOW BEFORE FINALIZING ON ONE SOLUTION OVER THE OTHER. THE ECMWF HAS AN OBVIOUS TROUGH OVER NORTHERN MEXICO BY TUESDAY MORNING...SO WE SHOULD KNOW ONE WAY OR THE OTHER BY THEN HOW THIS IS GOING TO PLAY OUT. AT ANY RATE...ASSUMING THIS UPPER LOW MOVES OVER NORTH TEXAS...CONTINUE TO EXPECT ONLY BENEFICIAL RAINFALL AS PARAMETERS ARE POOR FOR ORGANIZED SEVERE STORMS. KEPT HIGHS ON THE LOWER SPECTRUM OF GUIDANCE EXPECTING MOSTLY CLOUDY SKIES ASSOCIATED WITH THE UPPER LOW. THURSDAY AND FRIDAY...MODELS ARE SHOWING THE UPPER TROUGH OVER THE NORTHWESTERN CONUS KICKING OUT OVER THE NORTHERN AND CENTRAL PLAINS WEDNESDAY NIGHT INTO THURSDAY. THIS ACTION MAY SEND A SQUALL LINE SOUTH OR SOUTHEAST TOWARDS THE CWA WEDNESDAY NIGHT INTO THURSDAY MORNING. THIS SYSTEM MAY ALSO SEND A COLD FRONT SOUTH ACROSS THE PLAINS RESULTING IN ANOTHER SQUALL LINE THAT MAY MAKE A DIVE TO THE SOUTH TOWARDS NORTH TEXAS THURSDAY AFTERNOON THROUGH EARLY FRIDAY MORNING. LEFT SOME LOW POPS IN OVER THE NORTHERN PORTIONS OF THE CWA DURING THESE PERIODS AS A RESULT. WILL NOT HAVE MUCH CONFIDENCE IN THE LIKELIHOOD OF SQUALL LINE BEHAVIOR UNTIL WE GET CLOSER TO THE END OF THE WEEK. NEXT WEEKEND...MOST GUIDANCE HAS BEEN SHOWING THAT WE WILL BE BACK UNDER THE INFLUENCE OF UPPER LEVEL RIDGING NEXT WEEKEND...SO KEPT A DRY FORECAST IN PLACE. THE 00Z ECMWF WAS HINTING AT A WEAK...PROBABLY CONVECTIVELY GENERATED...MID-LEVEL LOW PRESSURE SYSTEM GETTING STUCK IN THE RIDGE ALOFT AND DRIFTING AROUND OVER NORTH TEXAS NEXT WEEKEND. THE GFS ON THE OTHER HAND BRINGS A WEAK SOUTHERN STREAM UPPER TROUGH OVER SOUTH TEXAS BEFORE MOVING IT NORTHEAST OVER EAST TEXAS SATURDAY NIGHT. CONFIDENCE IN EITHER OF THESE VERY SMALL SCALE FEATURES 6-7 DAYS OUT IS LOW. UPPER LEVEL RIDGING HAS BEEN THE MOST CONSISTENT SOLUTION OVER THE PAST COUPLE OF DAYS...SO DECIDED TO STICK WITH THIS DRY FORECAST AND SOLUTION AT THIS TIME. WILL HOLD OFF ON JUMPING ON SMALL PROBABILITY ALTERNATIVE SOLUTIONS UNLESS MODELS CONVERGE AND AGREE ON ONE OF THEM IN PARTICULAR IN LATER FORECASTS. CAVANAUGH && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 76 92 76 90 76 / 5 0 0 10 10 WACO, TX 75 90 74 89 74 / 5 5 0 10 10 PARIS, TX 74 88 73 88 73 / 5 0 0 5 10 DENTON, TX 75 90 74 90 75 / 5 0 0 5 10 MCKINNEY, TX 75 90 76 90 75 / 5 0 0 5 10 DALLAS, TX 75 90 75 90 76 / 5 0 0 10 10 TERRELL, TX 77 92 78 91 76 / 5 0 0 10 10 CORSICANA, TX 75 88 75 88 75 / 5 5 0 20 10 TEMPLE, TX 75 89 75 89 75 / 5 5 0 20 10 MINERAL WELLS, TX 73 91 72 90 73 / 10 0 0 5 10 && .FWD WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 58/91
FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
639 PM CDT TUE JUN 17 2014 UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE .SHORT TERM...TONIGHT AND WEDNESDAY ISSUED AT 238 PM CDT TUE JUN 17 2014 LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW LOW PRESSURE ASSOCIATED WITH LAST NITES CONVECTION MOVING EAST ACROSS LAKE HURON. A CONVECTIVE OUTFLOW BOUNDARY EXTENDS FROM THIS SURFACE LOW ACROSS NORTHERN ILLINOIS AND CENTRAL IOWA WHERE CUMULUS CLOUDS LOOK AGITATED. INSTABILITY HAS BEEN BUILDING THROUGH THE DAY OVER SOUTHWEST MINNESOTA AND SOUTHERN IOWA BUT CONSIDERABLE CONVECTIVE INHIBITION IS PREVENTING THE NEXT THUNDERSTORM COMPLEX FROM DEVELOPING SO FAR. FARTHER WEST...A SHORTWAVE TROUGH IS MOVING NORTHEAST OVER NEBRASKA WHERE WEAK LOW PRESSURE RESIDES. ACROSS NORTHERN WISCONSIN...CU IS BUILDING OVER NE WISCONSIN WHERE LOW LEVEL CONVERGENCE IS OCCURRING BUT PLENTY OF INHIBITION IS PRESENT THERE AS WELL. WITH THE NEXT THUNDERSTORM COMPLEX ANTICIPATED TO DEVELOP OVER THE NORTHERN MISSISSIPPI VALLEY THIS EVENING...THE THREAT OF SEVERE STORMS REMAINS THE MAIN FORECAST CONCERN. TONIGHT...A SHORTWAVE TROUGH OVER THE CENTRAL PLAINS WILL LIFT NORTHEAST TOWARDS THE NORTHERN MISSISSIPPI VALLEY THIS EVENING AND INTO THE WESTERN GREAT LAKES OVERNIGHT. THE APPROACH OF THE SHORTWAVE COMBINED WITH LIFT ON THE NOSE OF THE LLJ AND DESTABILIZATION OF THE MID-LEVELS SHOULD LEAD TO A THUNDERSTORM COMPLEX DEVELOPING OVER SOUTHERN MINNESOTA AND NORTHERN IOWA LATER THIS AFTERNOON OR EARLY THIS EVENING. THE LATEST NUMERICAL GUIDANCE SHOWS A VARIETY OF TRACKS OF THIS COMPLEX WITH THE NAM/ECMWF TRACKING IT TOWARDS NORTHERN ILLINOIS...WHILE THE MESOMODELS EXPANDING IT TOWARDS MILWAUKEE. SINCE THE LLJ AND ELEVATED INSTABILITY WILL BE DIRECTED TOWARDS SOUTHERN WISCONSIN AND NORTHERN ILLINOIS...A SOUTHEAST TRACK SEEMS MORE PROBABLE. HOWEVER...SOME THUNDERSTORMS MAY STILL MOVE INTO CENTRAL AND EAST-CENTRAL WISCONSIN LATE THIS EVENING AND OVERNIGHT WITH THE APPROACH OF THE SHORTWAVE TROUGH. ELEVATED INSTABILITY WILL BE AROUND 1K-1.5K J/KG WHILE EFFECTIVE BULK SHEARS WILL BE APPROX. 30 KTS. SO APPEARS THAT A LOW END SEVERE THREAT IS STILL POSSIBLE...IF THE MAIN COMPLEX DOES NOT CUT OFF MOISTURE INFLOW FROM THE SOUTH. HEAVY RAIN WILL BE ALSO POSSIBLE SOUTH OF ROUTE 29 WHERE PWATS WILL BE UPWARDS OF 1.5 INCHES. LOWS IN THE UPPER 50S NORTH TO MIDDLE 60S SOUTH. WEDNESDAY...THE SHORTWAVE TROUGH WILL BE EXITING EASTERN WISCONSIN DURING THE MORNING WHICH WILL KEEP THE CHANCE OF SHOWERS AND STORMS GOING THROUGH THE AM HOURS OVER CENTRAL AND NORTHEAST WISCONSIN. THINK PRECIP WILL BE EXITING BY LATE IN THE MORNING AND THEN WINDS WILL SHIFT TO THE NORTHEAST WHICH WILL BRING IN COOLER AIR OFF THE GREAT LAKES. EVEN THOUGH THE 850MB BOUNDARY WILL STALL OUT OVER SOUTHERN WISCONSIN....AM THINKING THAT THE COOLER AND MORE STABLE AIR WILL KEEP PRECIP CHANCES SMALLER THAN THE CURRENT FORECAST SHOWS. HIGHS RANGING FROM THE MID 70S EAST TO LOW 80S WEST...COOLER LAKE SIDE. .LONG TERM...WEDNESDAY NIGHT THROUGH TUESDAY ISSUED AT 238 PM CDT TUE JUN 17 2014 CONVECTIVE POTENTIAL WEDNESDAY NIGHT INTO THE WEEKEND CONTINUES TO BE THE MAIN CONCERN. EARLY IN PERIOD MODELS ALL TRENDING TOWARD PUSHING PCPN OFF TO THE WEST...WITH EAST WINDS OUT OF SURFACE HIGH OVER HUDSON BAY FILTERING IN DRIER AIR OVER THE REGION. PCPN CHANCES INCREASE AGAIN THU NIGHT/FRI AS LOW AND SURFACE TROF SHIFT EAST. NOT OVERLY IMPRESSED WITH CHANCES FOR SEVERE AT THIS TIME WITH WEAK LLVL JET AND SHEAR. PLENTY OF MOISTURE REMAINS OVER REGION WITH MAIN ISSUE AGAIN CHANCE FOR HEAVY RAIN. TEMPERATURES TO REMAIN AT OR ABOVE NORMAL. WEAKENING UPPER LOW WILL MOVE INTO THE WESTERN GREAT LAKES REGION OVER THE WEEKEND...LINGERING INTO EARLY NEXT WEEK. PCPN CHANCES TO CONTINUE. && .AVIATION...FOR 00Z TAF ISSUANCE ISSUED AT 639 PM CDT TUE JUN 17 2014 DECENT FLYING WEATHER EXPECTED THIS EVENING ACROSS THE AREA WITH JUST SOME MIDDLE CLOUDS AND LIGHT SURFACE WINDS. SOME UNCERTAINTY AFTER THAT AS A COMPLEX OF THUNDERSTORMS IS EXPECTED TO FORM LATER TONIGHT OVER SOUTHERN MINNESOTA AND MOVE INTO CENTRAL AND POSSIBLY NORTHERN WISCONSIN LATE TONIGHT. IF THE ACTIVITY DOES MATERIALIZE THERE WILL BE MVFR AND LOCAL IFR CONDITIONS AFTER AROUND 09Z. WHATEVER ACTIVITY IS LEFT EARLY WEDNESDAY SHOULD EXIT BY MIDDAY WITH VFR CONDITIONS WEDNESDAY AFTERNOON. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....MPC LONG TERM......TE AVIATION.......RDM
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
108 PM CDT MON JUN 16 2014 UPDATED AVIATION PORTION FOR 18Z TAF ISSUANCE .SYNOPSIS... ISSUED AT 418 AM CDT MON JUN 16 2014 QUIET TODAY...THEN RATHER STORMY THROUGH MID-WEEK. UPPER FLOW ACRS THE CONUS IS QUITE STG AND PRETTY HIGHLY AMPLIFIED FOR EARLY SUMMER. THE LNGWV TROF POSN IS OVER THE INTERMOUNTAIN WEST...WITH RIDGING CENTERED ARND 85W. THE ERN RIDGE WL SHARPEN AND BUILD NWWD ACRS THE GREAT LAKES REGION AND INTO CENTRAL CANADA DURING THE LATTER HALF OF THE WORK WEEK...CAUSING THE WRN TROF POSN TO REFORM BACK OFFSHORE FM THE PAC NW BY NEXT WEEKEND. AS THOSE LARGE SCALE CHANGES OCCUR...THE MAJOR SHRTWV HEADING OUT OF THE WRN TROF WL BECOME SEPARATED FM THE MAIN WESTERLIES AND END UP DRIFTG EWD ACRS THE NRN PLAINS AS A CLOSED UPR LOW. THE GENERAL WSWLY UPR FLOW ACRS THE MIDWEST EARLY IN THE PERIOD WL ALLOW A LARGE POOL OF MOIST UNSTABLE AIR TO BECOME ESTABLISHED ACRS THE MIDDLE OF THE COUNTRY...WITH THE FCST AREA SITTING NR IT/S THE NERN EDGE. THAT IS A FAVORABLE LCN FOR MCS DEVELOPEMNT... WITH REPEAT EVENTS POSSIBLE...RESULTING IN HEAVY AND POSSIBLY EXCESSIVE RAINFALL EARLY IN THE PERIOD. PCPN CHCS LATER IN THE PERIOD BECOME TOUGHER TO GET A GOOD HANDLE ON DUE TO MODEL DIFFERENCES IN THE HANDING OF THE NRN PLAINS UPR LOW AND UNCERTAINTIES ABOUT THE STRENGTH/AMNT LOW-LEVEL RIDGING THAT WL EDGE INTO THE AREA AS THE ERN NOAM RIDGE SHARPENS BACK NWWD. WARM TEMPS AND RATHER HUMID CONDITIONS ARE EXPECTED EARLY IN THE FCST PERIOD...THEN TEMPS SHOULD EDGE BACK CLOSER TO SEASONAL NORMALS AND HUMIDITIES WL LIKELY BACK DOWN TOO. OF COURSE...ANY DAYS DOMINATED BY WIDESPREAD THUNERSTORMS COULD STILL BE COOL. && .SHORT TERM...TODAY...TONIGHT...AND TUESDAY ISSUED AT 418 AM CDT MON JUN 16 2014 LOOKS LIKE WE ARE HEADING INTO AN ACTIVE PERIOD AS GOOD PORTIONS OF THE FCST AREA HAVE BEEN OUTLOOKED WITH A SLGT RISK OF SVR WX ON THE SPC DAY 1...DAY 2...AND DAY 3 CONVECTIVE OUTLOOKS...INCLUDING SOME RISK OF SIGNIFICANT SEVERE. WI IS MENTIONED FOR POSSIBLE SVR DAY 4 ALSO...THOUGH WITH THE HIGHER CRITERIA NEEDED TO BE OUTLOOKED THAT FAR IN ADVANCE THE AREA WAS NOT FORMALLY INCLUDED. AND THAT/S JUST THE SVR RISKS...THERE IS AT LEAST AS MUCH CONCERN ABOUT THE POSSIBILITY OF EXCESSIVE RAINFALL AND FLASH FLOODING. BASIC SCENARIO WL BE FOR THE FRONTAL BOUNDARY THAT CROSSED THE AREA YDA TO SHIFT BACK NWD THROUGH THE PLAINS AND GET STRUNG-OUT W-E JUST S OF THE AREA. ORGANIZED SLY FLOW AT LOW-LEVELS WL FEED MOIST AND UNSTABLE AIR INTO THE BOUNDARY...LIKELY LEADING TO A SERIES OF CONVECTIVE EVENTS ALONG/N OF THE FRONT. WITH AMPLE SHEAR AND INSTABILITY...EACH EVENT WL LIKELY BEGIN AS A SERIES OF SVR CELLS...LIKELY SUPERCELLS...BEFORE GROWING UPSCALE INTO AN MCS. FCST ISSUES CENTER ON WHERE AND WHEN EACH ROUND OF CONVECTION WL OCCUR. THIS IS ALSO ONE OF THOSE SITUATIONS WHERE ANY INDIVIDUAL ROUND OF STORMS COULD ALTER THE LOCATION OF THE FRONT...SIGNIFICANTLY IMPACTING SUBSEQUENT ROUNDS. TDA SHOULD BE QUIET...BUT PLENTY OF SUNSHINE WL ALLOW TEMPS TO BECOME QUITE WARM. THE RAP MIXED OUT DWPTS AND ALLOWED TEMPS TO REACH THE LOW 90S WITH RATHER LOW HUMIDITIES ACRS THE AREA...BUT WAS AN OUTLIER. WENT WITH BLEND OF BEST PERFORMING GUIDANCE...OF WHICH BIAS-CORRECTED ECMWF TEMPS HAVE HANDS DOWN BEEN TOPS LATELY. THAT SUGGESTED TEMPS WELL INTO THE 80S AND DWPTS OF MAINLY MID-UPR 50S AS SOME MIXING OCCURS...BUT NOT AS MUCH AS ON THE RAP. MOISTURE TRANSPORT INTO THE AREA WL INCREASE SHARPLY THIS EVENING AS LLJ STRENTHENS AND GETS DIRECTED INTO WI. THE INITIAL MORE CELLULAR STORMS SHOULD BE TO OUR W...WITH MCS DEVELOPING AND HEADING EWD OVERNIGHT. MANY OF THE MODELS TAKE THE CORE OF THE MCS ACRS NRN WI...BUT BACKWARD PROPAGATING CORFIDI VECTORS INDICATE BACKBUILDING INTO THE LLJ IS POSSIBLE. SUSPECT THE SW/SRN PARTS OF THE FCST AREA ARE MOST AT RISK OF SVR/HEAVY RAIN...SO ADDED HVY RAIN ATTRIBUTE TO THE GRIDS IN THAT AREA. A FEW OF THE VERY HIGH- RES MODELS TOOK THE WHOLE COMPLEX THROUGH TO OUR S...WITH LITTLE PCPN ACRS THE FCST AREA. THOUGH THAT SEEMS LESS LIKELY...IT/S NOT IMPOSSIBLE. SO HELD BACK A LITTLE ON POPS /DID NOT GO BEYOND LIKELY/. ALSO HELD OFF ON ADDING ANY EXPLICIT SVR TO THE FCST UNTIL WE SEE WHERE INITIAL STORMS FIRE AND HOW THE EVOLVE. MOST LIKELY SCENARIO TUE IS FOR REMNANTS OF MCS TO EXIT THE AREA IN THE MORNING. AFTER THAT...IT WL TAKE SOME TIME FOR THE ATM TO RECOVER...SO TOOK POPS DOWN DURING THE MID-DAY...ESP ACRS THE N. BUT BY LATE IN THE DAY...DEVELOPMENT MAY COMMENCE AGAIN. BEST CHC WL BE OVER THE SRN PART OF THE FCST AREA...CLOSER TO WHERE OUTFLOW BOUNDARY FM PREVIOUS CONVECTION IS LIKELY TO BE LOCATED. PLAN TO HIT OVERALL SVR RISK THE NEXT FEW DAYS HARD IN THE HWO... THOUGH WON/T BE ABLE TO ADD MUCH IN THE WAY OF DETAILS YET. WL ALSO HOLD OFF ON ESF FOR NOW GIVEN REMAINING QUESTIONS ON THE LOCATION OF THE HEAVIEST RAINFALL. BUT WL HIT HVY RAIN/FLASH FLOODING POTENTIAL HARD IN THE HWO. .LONG TERM...TUESDAY NIGHT THROUGH SUNDAY ISSUED AT 418 AM CDT MON JUN 16 2014 SEVERAL ROUNDS OF THUNDERSTORMS ARE EXPECTED THROUGH THE PERIOD. THE FIRST CHANCE WILL BE TUESDAY NIGHT AND WEDNESDAY. SUSPECTING CONVECTION FROM MONDAY NIGHT AND TUESDAY STORMS WILL PUSH BOUNDARY FURTHER SOUTH THAN WHAT THE MODELS ARE INDICATING TONIGHT. AN EXPECTED SOUTHWARD PUSH TO THE FRONT WILL MORE THAN LIKELY FOCUS CONVECTION FURTHER SOUTH THAN MONDAY NIGHT AND TUESDAY STORMS. HAVE TRENDED HIGHEST CHANCES FURTHER SOUTH AND LOWERED RAIN CHANCES ACROSS THE FAR NORTH. INCREASING LOW LEVEL JET OF 40-45 KNOTS POINTS TO CENTRAL AND EAST-CENTRAL WISCONSIN...RIGHT ENTRANCE REGION OF 200MB JET STREAK AND 0-6KM SHEAR 0F 40 TO 50 KNOTS WOULD SUPPORT THE POTENTIAL FOR STRONG OR SEVERE THUNDERSTORMS ACROSS CENTRAL INTO EAST-CENTRAL WISCONSIN. LOCALLY HEAVY RAIN IS ALSO POSSIBLE. ANY LINGERING STORMS ACROSS NORTHEAST WISCONSIN WEDNESDAY MORNING SHOULD EXIT THE REGION BY NOON. THE BIG QUESTION IS WHAT HAPPENS WEDNESDAY AFTERNOON INTO WEDNESDAY NIGHT. THE LATEST CANADIAN AND ECMWF MODELS HAVE WEDNESDAY AFTERNOON MAINLY DRY AS AREA WILL BE WORKED OVER BY TWO MESO SCALE CONVECTIVE COMPLEXES AND BUILDING HIGH PRESSURE. THERE MAY BE A PROLONGED PERIOD OF DRY WEATHER WEDNESDAY AFTERNOON INTO WEDNESDAY NIGHT FOR THE ABOVE MENTIONED REASONS. BELIEVE THIS SCENARIO IS PLAUSIBLE AS MCS ACTIVITY USUALLY PUSHES THE BOUNDARY FURTHER SOUTH AND CANADIAN HIGH PRESSURE SYSTEMS USUALLY EXERT THEIR FORCE THIS TIME OF YEAR. IF THIS SCENARIO DOES PLAY OUT...THE NEXT CHANCE FOR STORMS WOULD BE LATE WEDNESDAY NIGHT OR THURSDAY MORNING ACROSS CENTRAL AND EAST CENTRAL WISCONSIN. OF NOTABLE INTEREST... THE CANADIAN/ECMWF KEEP THE FAR NORTHEAST DRY THROUGH THURSDAY AFTERNOON. NOT CONFIDENT ENOUGH THAT THIS SCENARIO WOULD PLAY OUT THIS FAR OUT. BY FRIDAY AND INTO THE WEEKEND...TIMING DIFFERENCES NOTED BETWEEN THE ECMWF/CANADIAN/GFS MODELS ON THE 500MB FEATURE THAT WOULD IMPACT THE SENSIBLE WEATHER BY NEXT WEEKEND. LITTLE CHANGES MADE TO THE FRIDAY THROUGH SUNDAY PERIOD. HIGH TEMPERATURES DURING THE PERIOD WILL BE TRICKY DEPENDING ON CLOUD COVER AND EXPECTED CONVECTION AT TIMES. FOR WEDNESDAY...HIGH TEMPERATURES MAY BE REACHED BY LATE MORNING OR EARLY AFTERNOON... THEN COOL OFF ACROSS PORTIONS OF NORTHEAST WISCONSIN AS WINDS TURN OFF THE COOLER BAY AND LAKE. DID LOWER MAX TEMPERATURES ON THIS DAY BY A DEGREE ACROSS GREEN BAY INTO THE LAKE SHORE REGION. && .AVIATION...FOR 18Z TAF ISSUANCE ISSUED AT 106 PM CDT MON JUN 16 2014 EXPECT VFR CONDITIONS THROUGHOUT THE DAY. THE MAIN CONCERN DURING THE TAF VALID PERIOD IS THE PATH OF A THUNDERSTORM COMPLEX FORECAST TO PASS THROUGH THE STATE TONIGHT INTO EARLY TUESDAY. MOSTLY MVFR CIGS AND MVFR OR IFR VSBYS CAN BE EXPECTED WITH THE STORMS THAT WILL ALSO PRODUCE STRONG WINDS AND HEAVY RAINFALL. LARGE HAIL IS ALSO POSSIBLE. SOME MVFR FOG AND MVFR CIGS MAY PERSIST THROUGHOUT MUCH OF THE MORNING. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS.......SKOWRONSKI SHORT TERM.....SKOWRONSKI LONG TERM......ECKBERG AVIATION.......MG
FORECAST DISCUSSION FOR ROUTINE MORNING FORECAST ISSUANCE

.SYNOPSIS... ISSUED AT 418 AM CDT MON JUN 16 2014 QUIET TODAY...THEN RATHER STORMY THROUGH MID-WEEK. UPPER FLOW ACRS THE CONUS IS QUITE STG AND PRETTY HIGHLY AMPLIFIED FOR EARLY SUMMER. THE LNGWV TROF POSN IS OVER THE INTERMOUNTAIN WEST...WITH RIDGING CENTERED ARND 85W. THE ERN RIDGE WL SHARPEN AND BUILD NWWD ACRS THE GREAT LAKES REGION AND INTO CENTRAL CANADA DURING THE LATTER HALF OF THE WORK WEEK...CAUSING THE WRN TROF POSN TO REFORM BACK OFFSHORE FM THE PAC NW BY NEXT WEEKEND. AS THOSE LARGE SCALE CHANGES OCCUR...THE MAJOR SHRTWV HEADING OUT OF THE WRN TROF WL BECOME SEPARATED FM THE MAIN WESTERLIES AND END UP DRIFTG EWD ACRS THE NRN PLAINS AS A CLOSED UPR LOW. THE GENERAL WSWLY UPR FLOW ACRS THE MIDWEST EARLY IN THE PERIOD WL ALLOW A LARGE POOL OF MOIST UNSTABLE AIR TO BECOME ESTABLISHED ACRS THE MIDDLE OF THE COUNTRY...WITH THE FCST AREA SITTING NR IT/S THE NERN EDGE. THAT IS A FAVORABLE LCN FOR MCS DEVELOPEMNT... WITH REPEAT EVENTS POSSIBLE...RESULTING IN HEAVY AND POSSIBLY EXCESSIVE RAINFALL EARLY IN THE PERIOD. PCPN CHCS LATER IN THE PERIOD BECOME TOUGHER TO GET A GOOD HANDLE ON DUE TO MODEL DIFFERENCES IN THE HANDING OF THE NRN PLAINS UPR LOW AND UNCERTAINTIES ABOUT THE STRENGTH/AMNT LOW-LEVEL RIDGING THAT WL EDGE INTO THE AREA AS THE ERN NOAM RIDGE SHARPENS BACK NWWD. WARM TEMPS AND RATHER HUMID CONDITIONS ARE EXPECTED EARLY IN THE FCST PERIOD...THEN TEMPS SHOULD EDGE BACK CLOSER TO SEASONAL NORMALS AND HUMIDITIES WL LIKELY BACK DOWN TOO. OF COURSE...ANY DAYS DOMINATED BY WIDESPREAD THUNERSTORMS COULD STILL BE COOL. && .SHORT TERM...TODAY...TONIGHT...AND TUESDAY ISSUED AT 418 AM CDT MON JUN 16 2014 LOOKS LIKE WE ARE HEADING INTO AN ACTIVE PERIOD AS GOOD PORTIONS OF THE FCST AREA HAVE BEEN OUTLOOKED WITH A SLGT RISK OF SVR WX ON THE SPC DAY 1...DAY 2...AND DAY 3 CONVECTIVE OUTLOOKS...INCLUDING SOME RISK OF SIGNIFICANT SEVERE. WI IS MENTIONED FOR POSSIBLE SVR DAY 4 ALSO...THOUGH WITH THE HIGHER CRITERIA NEEDED TO BE OUTLOOKED THAT FAR IN ADVANCE THE AREA WAS NOT FORMALLY INCLUDED. AND THAT/S JUST THE SVR RISKS...THERE IS AT LEAST AS MUCH CONCERN ABOUT THE POSSIBILITY OF EXCESSIVE RAINFALL AND FLASH FLOODING. BASIC SCENARIO WL BE FOR THE FRONTAL BOUNDARY THAT CROSSED THE AREA YDA TO SHIFT BACK NWD THROUGH THE PLAINS AND GET STRUNG-OUT W-E JUST S OF THE AREA. ORGANIZED SLY FLOW AT LOW-LEVELS WL FEED MOIST AND UNSTABLE AIR INTO THE BOUNDARY...LIKELY LEADING TO A SERIES OF CONVECTIVE EVENTS ALONG/N OF THE FRONT. WITH AMPLE SHEAR AND INSTABILITY...EACH EVENT WL LIKELY BEGIN AS A SERIES OF SVR CELLS...LIKELY SUPERCELLS...BEFORE GROWING UPSCALE INTO AN MCS. FCST ISSUES CENTER ON WHERE AND WHEN EACH ROUND OF CONVECTION WL OCCUR. THIS IS ALSO ONE OF THOSE SITUATIONS WHERE ANY INDIVIDUAL ROUND OF STORMS COULD ALTER THE LOCATION OF THE FRONT...SIGNIFICANTLY IMPACTING SUBSEQUENT ROUNDS. TDA SHOULD BE QUIET...BUT PLENTY OF SUNSHINE WL ALLOW TEMPS TO BECOME QUITE WARM. THE RAP MIXED OUT DWPTS AND ALLOWED TEMPS TO REACH THE LOW 90S WITH RATHER LOW HUMIDITIES ACRS THE AREA...BUT WAS AN OUTLIER. WENT WITH BLEND OF BEST PERFORMING GUIDANCE...OF WHICH BIAS-CORRECTED ECMWF TEMPS HAVE HANDS DOWN BEEN TOPS LATELY. THAT SUGGESTED TEMPS WELL INTO THE 80S AND DWPTS OF MAINLY MID-UPR 50S AS SOME MIXING OCCURS...BUT NOT AS MUCH AS ON THE RAP. MOISTURE TRANSPORT INTO THE AREA WL INCREASE SHARPLY THIS EVENING AS LLJ STRENTHENS AND GETS DIRECTED INTO WI. THE INITIAL MORE CELLULAR STORMS SHOULD BE TO OUR W...WITH MCS DEVELOPING AND HEADING EWD OVERNIGHT. MANY OF THE MODELS TAKE THE CORE OF THE MCS ACRS NRN WI...BUT BACKWARD PROPAGATING CORFIDI VECTORS INDICATE BACKBUILDING INTO THE LLJ IS POSSIBLE. SUSPECT THE SW/SRN PARTS OF THE FCST AREA ARE MOST AT RISK OF SVR/HEAVY RAIN...SO ADDED HVY RAIN ATTRIBUTE TO THE GRIDS IN THAT AREA. A FEW OF THE VERY HIGH- RES MODELS TOOK THE WHOLE COMPLEX THROUGH TO OUR S...WITH LITTLE PCPN ACRS THE FCST AREA. THOUGH THAT SEEMS LESS LIKELY...IT/S NOT IMPOSSIBLE. SO HELD BACK A LITTLE ON POPS /DID NOT GO BEYOND LIKELY/. ALSO HELD OFF ON ADDING ANY EXPLICIT SVR TO THE FCST UNTIL WE SEE WHERE INITIAL STORMS FIRE AND HOW THE EVOLVE. MOST LIKELY SCENARIO TUE IS FOR REMNANTS OF MCS TO EXIT THE AREA IN THE MORNING. AFTER THAT...IT WL TAKE SOME TIME FOR THE ATM TO RECOVER...SO TOOK POPS DOWN DURING THE MID-DAY...ESP ACRS THE N. BUT BY LATE IN THE DAY...DEVELOPMENT MAY COMMENCE AGAIN. BEST CHC WL BE OVER THE SRN PART OF THE FCST AREA...CLOSER TO WHERE OUTFLOW BOUNDARY FM PREVIOUS CONVECTION IS LIKELY TO BE LOCATED. PLAN TO HIT OVERALL SVR RISK THE NEXT FEW DAYS HARD IN THE HWO... THOUGH WON/T BE ABLE TO ADD MUCH IN THE WAY OF DETAILS YET. WL ALSO HOLD OFF ON ESF FOR NOW GIVEN REMAINING QUESTIONS ON THE LOCATION OF THE HEAVIEST RAINFALL. BUT WL HIT HVY RAIN/FLASH FLOODING POTENTIAL HARD IN THE HWO. .LONG TERM...TUESDAY NIGHT THROUGH SUNDAY ISSUED AT 418 AM CDT MON JUN 16 2014 SEVERAL ROUNDS OF THUNDERSTORMS ARE EXPECTED THROUGH THE PERIOD. THE FIRST CHANCE WILL BE TUESDAY NIGHT AND WEDNESDAY. SUSPECTING CONVECTION FROM MONDAY NIGHT AND TUESDAY STORMS WILL PUSH BOUNDARY FURTHER SOUTH THAN WHAT THE MODELS ARE INDICATING TONIGHT. AN EXPECTED SOUTHWARD PUSH TO THE FRONT WILL MORE THAN LIKELY FOCUS CONVECTION FURTHER SOUTH THAN MONDAY NIGHT AND TUESDAY STORMS. HAVE TRENDED HIGHEST CHANCES FURTHER SOUTH AND LOWERED RAIN CHANCES ACROSS THE FAR NORTH. INCREASING LOW LEVEL JET OF 40-45 KNOTS POINTS TO CENTRAL AND EAST-CENTRAL WISCONSIN...RIGHT ENTRANCE REGION OF 200MB JET STREAK AND 0-6KM SHEAR 0F 40 TO 50 KNOTS WOULD SUPPORT THE POTENTIAL FOR STRONG OR SEVERE THUNDERSTORMS ACROSS CENTRAL INTO EAST-CENTRAL WISCONSIN. LOCALLY HEAVY RAIN IS ALSO POSSIBLE. ANY LINGERING STORMS ACROSS NORTHEAST WISCONSIN WEDNESDAY MORNING SHOULD EXIT THE REGION BY NOON. THE BIG QUESTION IS WHAT HAPPENS WEDNESDAY AFTERNOON INTO WEDNESDAY NIGHT. THE LATEST CANADIAN AND ECMWF MODELS HAVE WEDNESDAY AFTERNOON MAINLY DRY AS AREA WILL BE WORKED OVER BY TWO MESO SCALE CONVECTIVE COMPLEXES AND BUILDING HIGH PRESSURE. THERE MAY BE A PROLONGED PERIOD OF DRY WEATHER WEDNESDAY AFTERNOON INTO WEDNESDAY NIGHT FOR THE ABOVE MENTIONED REASONS. BELIEVE THIS SCENARIO IS PLAUSIBLE AS MCS ACTIVITY USUALLY PUSHES THE BOUNDARY FURTHER SOUTH AND CANADIAN HIGH PRESSURE SYSTEMS USUALLY EXERT THEIR FORCE THIS TIME OF YEAR. IF THIS SCENARIO DOES PLAY OUT...THE NEXT CHANCE FOR STORMS WOULD BE LATE WEDNESDAY NIGHT OR THURSDAY MORNING ACROSS CENTRAL AND EAST CENTRAL WISCONSIN. OF NOTABLE INTEREST... THE CANADIAN/ECMWF KEEP THE FAR NORTHEAST DRY THROUGH THURSDAY AFTERNOON. NOT CONFIDENT ENOUGH THAT THIS SCENARIO WOULD PLAY OUT THIS FAR OUT. BY FRIDAY AND INTO THE WEEKEND...TIMING DIFFERENCES NOTED BETWEEN THE ECMWF/CANADIAN/GFS MODELS ON THE 500MB FEATURE THAT WOULD IMPACT THE SENSIBLE WEATHER BY NEXT WEEKEND. LITTLE CHANGES MADE TO THE FRIDAY THROUGH SUNDAY PERIOD. HIGH TEMPERATURES DURING THE PERIOD WILL BE TRICKY DEPENDING ON CLOUD COVER AND EXPECTED CONVECTION AT TIMES. FOR WEDNESDAY...HIGH TEMPERATURES MAY BE REACHED BY LATE MORNING OR EARLY AFTERNOON... THEN COOL OFF ACROSS PORTIONS OF NORTHEAST WISCONSIN AS WINDS TURN OFF THE COOLER BAY AND LAKE. DID LOWER MAX TEMPERATURES ON THIS DAY BY A DEGREE ACROSS GREEN BAY INTO THE LAKE SHORE REGION. && .AVIATION...FOR 12Z TAF ISSUANCE ISSUED AT 418 AM CDT MON JUN 16 2014 AFTER ANY PATCHY FG IN FAR NERN WI DISSIPATES EARLY THIS MORNING...VFR CONDITIONS EXPECTED INTO THIS EVENING. CONDITIONS WL DETERIORATE RAPIDLY OVERNIGHT IN AREAS AFFECTED BY THE MCS. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS.......SKOWRONSKI SHORT TERM.....SKOWRONSKI LONG TERM......ECKBERG AVIATION.......SKOWRONSKI
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1052 PM MDT SUN JUN 15 2014 .UPDATE... ISSUED AT 1000 PM MDT SUN JUN 15 2014 ISSUED A QUICK UPDATE TO DROP POPS IN THE EAST. LATEST OBSERVATIONS INDICATE WE HAVE STABILIZED FOR THE MOST PART WITH A SMALL AMOUNT OF CAPE LEFT AROUND SCOTTSBLUFF...SIDNEY AND ALLIANCE BUT INSTABILITY ON DOWNWARD TREND. LATEST HRRR INDICATING OVERNIGHT ROUND OF ISOLATED STORMS MOST LIKELY TO FIRE WELL OUT TO THE EAST OF OUR AREA. 02/GARMON && .SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT) ISSUED AT 311 PM MDT SUN JUN 15 2014 TOWERING CU IS DEVELOPING OVER THE MOUNTAINS EARLY THIS AFTERNOON...AND ALONG A BOUNDARY THAT EXTENDS FROM THE SOUTHERN LARAMIE RANGE EASTWARD INTO THE NEBRASKA PANHANDLE. THIS BOUNDARY DEVELOPED ALONG THE INTERFACE BETWEEN SOUTHERLY SFC FLOW OFF THE CHEYENNE RIDGE AND WEST-SOUTHWESTERLY FLOW FURTHER TO THE NORTH. MID/UPPER LEVEL CIRRUS FROM THIS MORNING HAS SHIFTED NORTH OVER THE NORTHERN COUNTIES AND HAS SUPPRESSED CONVECTION A BIT HERE. MESOANALYSIS SHOWS LOW VALUES OF CAPE WITHIN THE SOUTHERN CLEAR SLOT WITH READINGS OF 250 J/KG OR LESS...WITH LESS INSTABILITY ELSEWHERE. STILL THINKING AREAS SOUTH OF THIS BOUNDARY IN THE ZONE OF WEAK INSTABILITY WILL SEE A FEW THUNDERSTORMS DEVELOP LATE THIS AFTERNOON AS THE WEAK SHORTWAVE MOVES OVERHEAD. THEN AS THE LOW LEVEL JET DEVELOPS THIS EVENING OVER THE PLAINS WITH MOISTURE ADVECTION INCREASING AS WELL...COULD SEE A FEW WEAK ELEVATED STORMS DEVELOP OVER SOUTHERN AND EASTERN PORTIONS OF THE PANHANDLE OVERNIGHT. FLOW ALOFT WILL BACK TO THE SOUTHWEST IN ADVANCE OF AN UPPER LOW DIGGING INTO THE PACNW ON MONDAY. MODELS STILL POINT AT HIGHER DEWS ADVECTING INTO NORTHERN PORTIONS OF THE FORECAST AREA SO WILL MAINTAIN MENTION FOR WIDELY SCATTERED AFTERNOON T-STORMS NORTH OF A LINE FROM THE NORTHERN LARAMIE RANGE TO ALLIANCE. A STRENGTHENING SFC LOW OVER THE PLAINS IN ADVANCE OF THIS UPPER LOW WILL INTENSIFY THE SW-NE PRESSURE GRADIENT OVER THE CWA...THUS EXPECT WINDS TO BECOME MODERATE TO STRONG IN THE WIND PRONE AREAS WEST OF THE LARAMIE RANGE IN THE AFTERNOON. MUCH WARMER TEMPS AND DRIER AIR WILL OCCUR AS WELL IN THIS SOUTHWEST FLOW PATTERN...SO HUMIDITIES WILL DROP INTO THE LOW TEENS FOR THIS AREA. FUELS ARE STILL IN GREEN UP SO FIRE CONCERNS ARE MINIMAL...BUT THIS PATTERN WILL CERTAINLY HELP TO DRY THESE FUELS OUT SOMEWHAT. THE UPPER LOW WILL SLOWLY SLIDE SOUTHEAST INTO THE GREAT BASIN ON TUESDAY WITH THE ASSOCIATED FRONT MOVING INTO THE FORECAST AREA BY TUESDAY NIGHT. WILL SEE SHOWERS AND T-STORMS DEVELOP TUESDAY AFTERNOON AHEAD OF THE FRONT AS IT APPROACHES WITH THIS ACTIVITY CONTINUING THROUGH THE EVENING. AS THE UPPER LOW DIGS...FLOW ALOFT WILL AMPLIFY FURTHER AND WILL SHIFT THE AXIS OF MOISTURE BACK SLIGHTLY TO THE WEST. THIS COULD KEEP THE OVERNIGHT PERIOD THROUGH WEDNESDAY MORNING DRY. .LONG TERM...(WEDNESDAY THROUGH SUNDAY) ISSUED AT 311 PM MDT SUN JUN 15 2014 MEDIUM RANGE MODELS CONTINUE TO STRUGGLE WITH THE PLACEMENT OF THE UPPER LEVEL LOW...CURRENTLY ALONG THE COASTLINE OF BRITISH COLUMBIA...AS IT DIGS SOUTH ACROSS THE PACIFIC NORTHWEST EARLY THIS WEEK. THIS LOW IS THEN FORECAST TO STALL AND MOVE EASTWARD. SEVERAL DAYS AGO...MOST MODELS WERE SHOWING THIS LOW MOVING ACROSS WYOMING AND BRINGING WIDESPREAD SHOWERS AND TSTORMS ALONG WITH MUCH COOLER TEMPERATURES TO THE AREA. MOST MODELS HAVE TRENDING FURTHER NORTH WITH THE LOW IN THE LAST 24 TO 36 HOURS...WITH THE CURRENT 12Z ECMWF/GEM AND NAM SHOWING THE LOW EJECTING NORTHEAST INTO MONTANA BY TUESDAY NIGHT AND WEDNESDAY. THE FURTHEST SOUTH IS THE GFS AND THE GFS ENSEMBLE. THE LOCATION OF THIS LOW WILL BE KEY IN DETERMINING PRECIP CHANCES AND PRECIP AMOUNTS WEDNESDAY AND THURSDAY. A COOLER AIRMASS MOVING INTO THE AREA LOOKS NEARLY CERTAIN REGARDLESS OF THE TRACK. KEPT TEMPERATURES BELOW NORMAL...ALTHOUGH THERE IS UNCERTAINTY WITH HIGH TEMPERATURES ON WEDNESDAY DUE TO THE TIMING OF THE PACIFIC FRONT. KEPT POP BETWEEN 15 TO 25 PERCENT ACROSS MOST OF WYOMING ON WEDNESDAY DUE TO UNCERTAINTY IN THE POSITION OF THE LOW. THERE IS HIGHER CONFIDENCE THAT THE HIGH PLAINS EAST OF I25 WILL SEE A GREATER COVERAGE OF SHOWERS AND TSTORMS LATE WEDNESDAY AND INTO WEDNESDAY NIGHT...SO INCREASED POP UP TO 40 PERCENT EAST OF I25. KEPT HIGH TEMPERATURES IN THE 60S AND 70S FOR NOW...ALTHOUGH THIS MAY CHANGE IN THE FUTURE DEPENDING ON THE TIMING OF THE FRONT. FOR LATE IN THE WEEK...THE ONLY FORECAST CONCERN IS THE POSITION OF THE UPPER LEVEL LOW AS IT ATTEMPTS TO MOVE EASTWARD THROUGH FRIDAY. MODELS SHOW A REX BLOCK ATTEMPTING TO FORM...WHICH MAY ALLOW THE LOW TO STALL SOMEWHERE OVER THE NORTHERN PLAINS AND COOLER AIR TO REMAIN OVER PORTIONS OF THE AREA. STARTED TO INCREASE TEMPERATURES BACK TO NEAR NORMAL...BUT BELOW MOS CONSIDERING THE POSITION OF THE LOW. FOR THE WEEKEND...DAYTIME TEMPERATURES WILL RETURN TO THE 80S AND NEAR 90 ACROSS THE LOWER ELEVATIONS AS A BROAD UPPER LEVEL HIGH DEVELOPS OVER THE SOUTH. WITH SOUTHERLY FLOW ALOFT...MODELS INDICATE TROPICAL MOISTURE PUSHING NORTHWARD OVER THE SPINE OF THE ROCKY MOUNTAINS WITH SEVERAL WEAK DISTURBANCES ALOFT MOVING OVER THE FORECAST AREA. ADDED A SLIGHT CHANCE OF THUNDERSTORMS OVER PORTIONS OF THE AREA FOR SATURDAY AND SUNDAY AFTERNOON/EVENING TIME FRAMES. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY EVENING) ISSUED AT 1049 PM MDT SUN JUN 15 2014 VFR CONDITIONS OVERNIGHT THROUGH THE DAY MONDAY. WINDS WILL BE ON THE INCREASE AFTER 15Z OR SO...ESPECIALLY OUT WEST OF THE LARAMIE RANGE. COULD SEE SCATTERED SHOWERS AND THUNDERSTORMS NORTH OF A RAWLINS TO WHEATLAND TO ALLIANCE LINE MONDAY AFTERNOON AND EARLY EVENING. SOUTH OF THIS LINE SHOULD REMAIN DRY. && .FIRE WEATHER... ISSUED AT 311 PM MDT SUN JUN 15 2014 THERE IS A CHANCE FOR ISOLATED SHOWERS/STORMS FOR AREAS ALONG AND EAST OF THE SOUTHERN LARAMIE RANGE THIS AFTERNOON...AND FOR SOUTHERN PORTIONS OF THE NEBRASKA PANHANDLE TONIGHT. WARM AND BREEZY CONDITIONS WILL OCCUR ON MONDAY AND TUESDAY...WITH HUMIDITIES EXPECTED TO FALL INTO THE LOWER TEENS. SOUTHWEST WIND GUSTS WILL APPROACH 30-40 MPH IN THE AFTERNOON ALONG AND WEST OF THE LARAMIE RANGE. ALTHOUGH FUELS ARE STILL IN GREEN-UP...EXPECT SIGNIFICANT DRYING TO OCCUR UNDER THESE CONDITIONS. A FEW T-STORMS ARE POSSIBLE FOR NORTHERN PORTIONS OF THE DISTRICT ON MONDAY AND FOR MUCH OF SOUTHEAST WYOMING ON TUESDAY. THIS ACTIVITY WILL BE HIGH BASED...PRODUCE VERY LITTLE RAINFALL ALONG WITH THE POTENTIAL FOR VERY GUSTY AND ERRATIC WINDS. A COLD FRONT MOVING THROUGH THE AREA ON WEDNESDAY WILL BRING A BETTER CHANCE FOR T-STORMS AND WETTING RAINS. && .HYDROLOGY... ISSUED AT 311 PM MDT SUN JUN 15 2014 RIVER LEVELS WILL CONTINUE TO DECREASE SLOWLY OVER THE NEXT COUPLE OF DAYS...WITH THE UPPER NORTH PLATTE RIVER AT SARATOGA AND THE LARAMIE RIVER AT LARAMIE LOOKING TO FALL BELOW ACTION STAGE BY MIDWEEK. SLIGHTLY ABOVE AVERAGE HIGHS WILL RETURN FOR MONDAY AND TUESDAY BEFORE COOLING ONCE AGAIN WEDNESDAY AND THURSDAY. STILL SOME HEALTHY SNOW PACK ABOVE 10000 FEET IN THE SNOWY AND SIERRA MADRE RANGES...SO A RAPID WARM UP COULD RELEASE THIS WATER FOR FUTURE RISES IN RIVERS. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && $$ SHORT TERM...RJM LONG TERM...TJT AVIATION...CLAYCOMB FIRE WEATHER...RJM HYDROLOGY...RJM
AREA FORECAST DISCUSSION...UPDATED
NWS RENO NV
1004 PM PDT TUE JUN 17 2014 .UPDATE... FRONTAL BOUNDARY CONTINUES TO PUSH THROUGH WESTERN NEVADA THIS EVENING. IT KICKED UP QUITE A BIT OF DUST IN CHURCHILL AND MINERAL COUNTY THIS EVENING WITH VISIBILITY DROPPING TO AS LOW AS ONE MILE AT TIMES AROUND HIGHWAY 95 ALONG WALKER LAKE AND AROUND THE HAWTHORNE AREA. GUSTY WINDS WILL CONTINUE THROUGH MIDNIGHT, ALONG WITH THE AREAS OF BLOWING DUST IN MINERAL COUNTY. HOON && .PREVIOUS DISCUSSION... /ISSUED 433 PM PDT TUE JUN 17 2014/ UPDATE... QUICK UPDATE THIS AFTERNOON TO EXTEND THE SHOWERS AND THUNDERSTORM CHANCES SOUTH OF RENO INTO CARSON CITY AND LAKE TAHOE AS THE SHORTWAVE PUSHES INTO NORTHERN NEVADA. THERE IS CONVECTIVE DEVELOPMENT OVER THE CARSON RANGE WEST OF RENO-CARSON AND COULD POTENTIALLY PRODUCE LIGHT RAIN, GUSTY WINDS AND POSSIBLY OCCASIONAL LIGHTNING. SHOWERS NORTH OF INTERSTATE 80 CONTINUE TO PUSH SOUTHWARD INTO THE PYRAMID LAKE AND LOVELOCK AREAS THIS AFTERNOON, BUT HAVE SO FAR REMAINED JUST SHOWERS WITH NO LIGHTNING STRIKES DETECTED. GUSTY OUTFLOW WINDS FROM THESE SHOWERS ARE ALSO POSSIBLE AND COULD CREATE SOME LOCALIZED BLOWING DUST NEAR DRY LAKE BEDS. PREVIOUS DISCUSSION... /ISSUED 224 PM PDT TUE JUN 17 2014/ SYNOPSIS... A COLD LOW PRESSURE SYSTEM WILL EXIT THE REGION AND RESULT IN DRIER CONDITIONS AND MUCH WARMER TEMPERATURES BEGINNING WEDNESDAY AFTERNOON AND PERSISTING THROUGH THE WEEKEND. A FEW COLDER SIERRA VALLEYS WILL DROP NEAR OR SLIGHTLY BELOW FREEZING TONIGHT WITH A FEW 30S IN OUTLYING COLDER VALLEYS IN WESTERN NEVADA. SHORT TERM... SHORTWAVE THAT BROUGHT SHOWERS AND MEASURABLE RAINFALL TO PARTS OF NORTHEAST CA AND NORTHWEST NV HAS EXITED WITH SUBSIDENCE AND DRIER AIR ALOFT HELPING TO ERODE CUMULUS FIELD ALONG THE EASTERN SIERRA AND WESTERN NV. SATELLITE IMAGERY SHOWS ANOTHER SHORTWAVE DROPPING SOUTHEASTWARD TOWARD THE AREA WHICH WILL TRACK MAINLY ACROSS NORTHWEST INTO CENTRAL NV ON BACK SIDE OF UPPER LOW WHERE INSTABILITY WILL BE MORE FAVORABLE THROUGH EARLY THIS EVENING FOR A FEW SHOWERS. THE NAM CONTINUES TO HOLD A NARROW BAND OF SHOWERS TOGETHER ON THE FAR WESTERN EDGE AS IT APPROACHES RENO 00Z-03Z. OTHER MODELS INCLUDING THE HRRR DO NOT SHOW THIS EXTENSION. CONFIDENCE IS LOW BUT WILL INCLUDE IT FOR AREAS JUST NORTH OF RENO INCLUDING PYRAMID LAKE. BEST FORCING/CONVERGENCE IS ACROSS NORTH CENTRAL-NORTHEAST NV WITH A THUNDERSTORM OR TWO POSSIBLE ACROSS THE BASIN AND RANGE. TEMPERATURES WILL BE QUITE COLD TONIGHT AS SKIES CLEAR AND WINDS DECREASE. THE AIRMASS IS NOT PARTICULARLY DRY AND THUS TEMPERATURES MAY NOT GET AS LOW AS SOME OF THE COLDEST MOS GUIDANCE. HOWEVER, COLDER SIERRA VALLEYS WILL LIKELY SEE A LIGHT FREEZE WITH EVEN SOME OF THE OUTLYING COLDER WESTERN NV VALLEYS DROPPING INTO THE 30S BY WEDNESDAY MORNING. IF YOUR LOW IS FORECAST TO DROP BELOW 40 DEGREES, YOU MAY WANT TO CONSIDER TAKING SOME GENERAL PRECAUTIONS TO PROTECT SENSITIVE PLANTS. HEIGHTS BEGIN TO RISE WEDNESDAY AFTERNOON INTO THURSDAY FOR A FAST WARMUP. TEMPERATURES IN COLDER SIERRA VALLEYS WILL NOT BE AS COLD THURSDAY MORNING ALTHOUGH THEY COULD STILL GET DOWN TO NEAR OR JUST ABOVE FREEZING FOR ONE MORE NIGHT. DAYTIME HIGHS WILL REMAIN JUST SHY OF NORMAL FOR WEDNESDAY BUT REBOUND TO ABOVE NORMAL FOR THURSDAY WITH 70S SIERRA VALLEYS AND 80S WESTERN NV. HOHMANN LONG TERM...FRIDAY THROUGH TUESDAY... THE LONG TERM FORECAST REMAINS UNCHANGED. THE REGION WILL REMAIN ANCHORED BETWEEN A NORTHEAST PACIFIC TROUGH AND ROCKIES/NORTHERN PLAINS RIDGE THROUGH THE LONG TERM FORECAST, WITH A FEW MINOR DISTURBANCES PERIODICALLY MOVING OVERHEAD. THE GFS REMAINS THE STRONGEST WITH THE FRIDAY DISTURBANCE ALTHOUGH EVEN IT IS SHIFTING NORTH WITH THE BEST LOW-MID LEVEL INSTABILITY AND FORCING OVER EXTREME NORTHEAST CALIFORNIA, NORTHWESTERN NEVADA AND OREGON. MEANWHILE, THE ECMWF/GEM LOOK VERY WEAK AND FLAT WITH FRIDAY`S DISTURBANCE WITH LITTLE INDICATION OF THUNDERSTORMS. THE OTHER THING OF SOME CONCERN FRIDAY WILL BE WINDS FOR NORTHEAST CALIFORNIA AND GENERALLY NORTH OF HIGHWAY 50 INTO FAR WESTERN NEVADA (SIERRA FRONT). GRADIENTS INCREASE WITH THE MOS HIGH TEMPERATURE BETWEEN THE SIERRA (TRUCKEE) AND WEST-CENTRAL NEVADA (LOVELOCK) IMPLYING INCREASED WINDS WITH GUSTS TO AROUND 30 MPH POSSIBLE FOR THE SIERRA FRONT. SATURDAY THROUGH TUESDAY, EASTERN CALIFORNIA AND WESTERN NEVADA WILL REMAIN IN FLAT SOUTHWEST-WEST FLOW ALOFT. THIS WILL BRING THE TYPICAL DAILY ZEPHYR BREEZES FOR THE EASTERN SIERRA AND OUT INTO WESTERN NEVADA. DEPENDING ON THE SMALL-SCALE, LOW CONFIDENCE DETAILS OF ANY WEAK UPPER DISTURBANCES MOVING OVERHEAD THE ZEPHYR MAY BE PERIODICALLY ENHANCED WITH AN INCREASED FIRE CONCERN. SNYDER AVIATION... AN UPPER DISTURBANCE, CURRENTLY LOCATED NEAR KAAT, IS MOVING AROUND THE LARGE UPPER TROUGH CENTERED OVER THE NORTHERN ROCKIES. THE DISTURBANCE IS EXPECTED TO KICK OFF A FEW LIGHT SHOWERS NORTH AND EAST OF KRNO, WITH A FEW THUNDERSTORMS POSSIBLE EAST AND NORTH OF A GERLACH TO PYRAMID LAKE TO KNFL LINE THROUGH SUNSET. BRIEF HIGHER TERRAIN OBSCURATION, SMALL HAIL (LESS THAN HALF-INCH) AND WIND GUSTS TO AROUND 30 KTS COULD ACCOMPANY ANY THUNDERSTORMS. LATE TONIGHT, THE MARTIS VALLEY NEAR KTRK COULD SEE PATCHY FOG. OTHERWISE, VFR CONDITIONS WITH MAINLY LIGHT WINDS (LESS THAN 8 KTS) WILL RETURN OVERNIGHT AND FOR WEDNESDAY AS HIGH PRESSURE BUILDS INTO CALIFORNIA. SNYDER && .REV WATCHES/WARNINGS/ADVISORIES... NV...NONE. CA...NONE. && $$ FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT... HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
325 AM MDT WED JUN 18 2014 .SHORT TERM...(TODAY THROUGH THURSDAY) ISSUED AT 324 AM MDT WED JUN 18 2014 DEEP UPPER LEVEL LOW OVER NORTHEAST IDAHO WILL LIFT NORTHEAST ACROSS MONTANA TODAY. THIS WILL HELP SWING SHRTWV ENERGY THROUGH THE FORECAST AREA LATER THIS MORNING AND THIS AFTERNOON. LIMITED MOISTURE FIELD WILL STILL BE ENOUGH TO SPARK SCATTERED SHOWERS AND THUNDERSTORMS THIS AFTERNOON...MAINLY ACROSS WESTERN COLORADO AS CONDITIONS DESTABILIZE WITH COOLING ALOFT. IN THE MEANTIME...SNOW SHOWERS ACROSS THE EASTERN UINTA MOUNTAINS AND HIGHER PEAKS IN EXTREME NORTHWEST COLORADO WILL CONTINUE THROUGH THIS MORNING...BEFORE TAPERING OFF AROUND 18Z PER LATEST HRRR GUIDANCE. WILL KEEP CURRENT WINTER WEATHER ADVISORY HIGHLIGHTS IN PLACE...WITH NO EXPANSION ANTICIPATED AS DEEPER POOL OF COLD AIR SHIFTS NORTHEAST INTO WYOMING...LEAVING THE NORTHERN MOUNTAINS IN WESTERN COLORADO WITH SNOW LEVELS OVER 12K. ELEVATED FIRE CONCERNS REMAIN IN PLAY ACROSS THE SOUTHWEST VALLEYS FROM CORTEZ EAST TO PAGOSA SPRINGS...AS THE COLD FRONT STALLS NEAR THE SAN JUANS. SO WILL KEEP RED FLAG WARNINGS IN PLACE. GUSTY WINDS SHOULD DIMINISH BY SUNSET...AND A FEW DAYTIME SHOWERS MAY LINGER INTO THE EVENING. A FINAL PV LOBE SWINGS ACROSS THE NORTH TOWARD MIDNIGHT BUT WITH INCREASING STABILITY AND SHRINKING MOISTURE...ONLY SOME CLOUDS ARE EXPECTED OVERNIGHT. WITH ENOUGH CLEARING...RADIATIONAL COOLING COULD ALLOW TEMPS TO DIP TO AROUND FREEZING IN THE CRAIG/MEEKER AREAS TONIGHT...WHERE A FREEZE WATCH REMAINS IN EFFECT. WEAKLY CYCLONIC FLOW CONTINUES ON THU WITH THE UPPER LOW OVER THE SASKATCHEWAN/MONTANA BORDER. AIR REMAINS DRY FOR LITTLE OTHER THAN SOME HIGH CLOUDS ACROSS THE NORTH. TEMPERATURES BEGIN TO MODERATE THU. .LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY) ISSUED AT 324 AM MDT WED JUN 18 2014 DRY AIR REMAINS THE MAJOR PLAYER FOR ERN UT/WRN CO THU NIGHT AND FRI. GFS/ECMWF SHOW SOME 500-300 MB PAC MOISTURE REACHING OUR AREA IN THE FORM OF HIGH CLOUDS FRI AFTERNOON IN WESTERLY FLOW. TEMPS CONTINUE TO REBOUND FROM THE MIDWEEK COOLDOWN. FAIRLY QUIET PERIOD CONTINUES THROUGH TUESDAY WITH TEMPERATURES CLIMBING TO THE PLUS SIDE OF NORMAL AS WE MOVE THROUGH THE WEEKEND. CONDITIONS LOOK DRY UNDER A RIDGE OF HIGH PRESSURE...BUT CANNOT RULE OUT AN ISOLATED STORM OVER THE HIGH COUNTRY MONDAY AND TUESDAY AS A SMIDGEN OF MOISTURE WORKS IN UNDER THE RIDGE. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING) ISSUED AT 324 AM MDT WED JUN 18 2014 BREEZY TO WINDY CONDITIONS WILL REMAIN IN PLACE ACROSS EASTERN UTAH AND WESTERN COLORADO AS A COLD FRONT CONTINUES TO MARCH EAST AND SOUTH. THE FRONT IS EXPECTED TO STALL NEAR THE SAN JUAN MOUNTAINS THIS MORNING BEFORE MAKING A FINAL PUSH ACROSS THE REGION AFTER 20Z THIS AFTERNOON. UPPER LEVEL ENERGY BRINGS SCATTERED SHOWERS AND THUNDERSTORMS TO NORTHEAST UTAH AND WESTERN COLORADO. SHOWERS END AFTER 03Z WITH CLEARING SKIES AND LIGHT WINDS EXPECTED FOR THE REMAINDER OF THE NIGHT. VFR CONDS EXPECTED TO HOLD AT ALL TERMINAL SITES THROUGH THE PERIOD. && .FIRE WEATHER... ISSUED AT 324 AM MDT WED JUN 18 2014 A RED FLAG WARNING REMAINS IN EFFECT FOR FIRE WEATHER ZONE 207 BELOW 9500 FEET BETWEEN NOON AND 700 PM MDT TODAY FOR CONTINUED GUSTY WEST TO SOUTHWEST WINDS AND LOW HUMIDITY. THE COLD FRONT WILL CLEAR THE AREA THIS EVENING...AND WINDS ARE EXPECTED TO DECREASE BEHIND THIS FRONTAL PASSAGE. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...RED FLAG WARNING FROM NOON TODAY TO 7 PM MDT THIS EVENING FOR COZ207. FREEZE WATCH FROM LATE TONIGHT THROUGH THURSDAY MORNING FOR COZ002. UT...WINTER WEATHER ADVISORY UNTIL NOON MDT TODAY FOR UTZ023. && $$ SHORT TERM...JDC/JAD LONG TERM...JAD/JDC AVIATION...JDC FIRE WEATHER...JDC
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
255 AM MDT WED JUN 18 2014 .SHORT TERM...(TODAY THROUGH TONIGHT ) ISSUED AT 255 AM MDT WED JUN 18 2014 AN UPPER LEVEL STORM SYSTEM WILL MOVE SLOWLY ACROSS THE NRN ROCKIES AS A DISTURBANCE MOVES EASTWARD ACROSS NRN CO THIS AFTN INTO THE EARLY EVENING HOURS. MEANWHILE AT THE SFC A COOL FNT WAS ALREADY MOVING ACROSS NERN CO EARLY THIS MORNING. THIS FNT WILL EVENTUALLY STALL OUT OVER THE PALMER DIVIDE AND THEN BEGIN TO LIFT NORTH AS A WRM FNT THIS AFTN AS SFC LOW PRES DEVELOPS NEAR DENVER. OVERALL SHOULD SEE SCT HIGH BASED SHOWERS AND STORMS DEVELOP OVER THE MTNS BY MIDDAY AND THEN SPREAD QUICKLY EASTWARD ACROSS THE PLAINS FM LATE AFTN THRU THE EARLY EVENING HOURS WITH THE BEST COVERAGE FM DENVER TO AKRON NORTHWARD. SOME DEEPER LOW LVL MOISTURE MAY MOVE INTO THE FAR NERN CORNER BY EARLY EVENING WHICH MAY LEAD TO A CHC OF A FEW SVR STORMS OVER THE FAR NERN PLAINS. CLOSER TO THE FRONT RANGE THE AIRMASS WILL BE DRIER HOWEVER WITH INCREASING MID LVL FLOW THE STORMS WILL PRODUCE GUSTY OUTFLOW WINDS. AS FOR HIGHS TODAY WILL KEEP READINGS IN THE LOWER TO MID 80S ACROSS NERN CO HOWEVER SOUTH OF THE WRM FNT READINGS COULD GET CLOSE TO 90 AS LOW LVL WINDS BECOME SWLY. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 255 AM MDT WED JUN 18 2014 MODELS SHOW AN UPPER TROUGH AXIS PUSHING EASTWARD ACROSS THE CWA THURSDAY. THURSDAY NIGHT THROUGH FRIDAY SHOWS ZONAL FLOW ALOFT FOR THE FORECAST AREA. DOWNWARD SYNOPTIC SCALE ENERGY IS PROGGED OVER THE CWA THURSDAY AND THURSDAY EVENING...THEN BENIGN ENERGY IS PROGGED INTO THE WEEKEND. LOW LEVEL WIND AND PRESSURE FIELDS HAVE EAST TO SOUTHEASTERLY BOUNDARY LAYER FLOW FOR THE CWA THURSDAY AND THURSDAY EVENING. ON FRIDAY AND FRIDAY EVENING...EAST- NORTHEASTERLY WINDS ARE INDICATED. CONCERNING MOISTURE...THERE IS LITTLE THURSDAY..BUT A BIT OVER THE EASTERN HALF BY AFTERNOON INTO THE EVENING. THE REST OF THE THURSDAY NIGHT AND FRIDAY ARE FAIRLY DRY TOO. THERE IS SOME UPPER LEVEL MOISTURE FRIDAY NIGHT. BOUNDARY LAYER DEW POINTS OVER THE PLAINS ARE IN THE 40S TO MID 50S F OVER THE PLAINS THROUGH THE PERIODS. THERE IS MINOR CAPE OVER THE FAR EAST LATE DAY THURSDAY...WITH HIGHER VALUES OVER MORE OF THE PLAINS FOR LATE DAY FRIDAY. VALUES OVER THE EASTERN BORDER ARE ABOUT 2000 J/KG AT 00Z FRIDAY AFTERNOON. THE QPF FIELDS HAVE A TAD OF MEASURABLE PRECIPITATION OVER THE PLAINS...MAINLY DURING THE LATE IN THE DAY PERIODS. WILL LEAVE POPS OUT FOR NOW THROUGH FRIDAY NIGHT. FOR TEMPERATURES...THURSDAY`S HIGHS ARE CLOSE TO TODAY`S. FRIDAY`S WARM UP ABOUT 2 C. FOR THE LATER DAYS...SATURDAY THROUGH TUESDAY...MODELS KEEP WEAK WEST TO SOUTHWESTERLY FLOW ALOFT FOR THE CWA WITH WEAK UPPER RIDGING AROUND. THERE IS SOME MOISTURE AROUND...ESPECIALLY SUNDAY THROUGH TUESDAY. THE AIRMASS IS COOLER MONDAY AND TUESDAY. && .AVIATION...(FOR THE TAFS THROUGH 12Z THURSDAY MORNING) ISSUED AT 255 AM MDT WED JUN 18 2014 WK FNT HAS MOVED INTO THE AREA EARLY THIS MORNING AND IS FCST TO STAY NRLY STATIONARY OR SLOWLY LIFT BACK TO THE NORTH BY EARLY AFTN. THE RAP AND HRRR DVLP A SFC LOW ALONG THIS BNDRY NR DENVER AND KEEP WINDS AT DIA BASCIALLY ESE THRU THE EARLY AFTN. BY 21Z THR RAP MOVES THE SFC LOW NORTH OF DENVER WITH WINDS BECOMING MORE WLY AND THEN NWLY BY 00Z. MEANWHILE THERE WILL BE SOME WDLY SCT HIGHER BASED STORMS BY 21Z WHICH MAY LINGER THRU 00Z BEFORE MOVING EAST OF THE AREA BY EARLY EVENING. WITH INCREASING MID LVL FLOW GUSTY OUTFLOW WINDS UP TO 50 MPH COULD OCCUR WITH THE CONVECTION. BY EARLY EVENING A COLD FNT WILL MOVE ACROSS THE AREA WITH WINDS BECOMING NNE FOR A FEW HOURS. BY 06Z WINDS SHOULD TREND TOWARD DRAINAGE AND CONTINUE THROUGH 12Z THU. && .BOU WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...RPK LONG TERM...RJK AVIATION...RPK
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1145 PM MDT TUE JUN 17 2014 .UPDATE... ISSUED AT 1117 PM MDT TUE JUN 17 2014 LOADED LATEST SURFACE OBSERVATIONS INTO FRONT END OF FORECAST GRIDS. NO OTHER CHANGES TO FORECAST AT THIS TIME. LW UPDATE ISSUED AT 855 PM MDT TUE JUN 17 2014 RED FLAG WARNING ALLOWED TO EXPIRE FOR TONIGHT. CONDITIONS HAVE SUBSIDED BELOW CRITICAL FIRE WEATHER LEVELS. ALSO...LOADED IN LATEST OBSERVATIONS. LW UPDATE ISSUED AT 651 PM MDT TUE JUN 17 2014 LOADED IN LATEST OBSERVATIONS. NO OTHER CHANGES TO FORECAST AT THIS TIME. LW && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 247 PM MDT TUE JUN 17 2014 .SHORT TERM...(TONIGHT AND TOMORROW) CURRENTLY...THE UPPER LOW WAS LOCATED OVER IDAHO THIS AFTN...PRODUCING STRONG SW FLOW ALOFT ACROSS THE 4 CORNERS AND COLORADO. THERE IS SLIGHTLY MORE MOISTURE AVAILABLE AS EVIDENCED BY A BIT MORE CU OVER THE MTS...BUT FOR THE MOST PART TODAY WAS VERY SIMILAR TO YESTERDAY WITH STRONG W-SW WINDS WITH GUSTS OF 35-45 MPH...SINGLE DIGIT RH READINGS AND MAX TEMPS IN THE UPPER 80S TO MID 90S FOR THE PLAINS...AND AROUND 80 F FOR THE HIGH VALLEYS. TONIGHT AND TOMORROW...THE UPPER SYSTEM IS FORECAST TO TRACK EAST ACROSS THE NORTHERN ROCKIES OVER THE NEXT 24 HRS...WITH A TIGHTENING OF THE PRES GRADIENT AND MOISTURE EDIFICATION EXPECTED LATE TONIGHT THROUGH WED. MODELS HAD INITIALLY HINTED AT SOME ISOLATED CONVECTION OVER THE SOUTHERN MES THIS EVE...BUT LATEST RADAR AND SATELLITE TRENDS AS WELL AS THE LATEST HRRR RUN POINTS TO A DRY NIGHT. THEREFORE...PULLED POPS TONIGHT. ONGOING FORKS HIGHLIGHTS FOR TONIGHT LOOK GOOD...AND WILL SHUT DOWN AT 9 PM. AS FOR TOMORROW...DECIDED TO UPGRADE THE WATCH TO A RED FLAG WARNING FOR EL PASO AND FREMONT COUNTIES SINCE THOSE ARE THE ONLY AREAS THAT REPORT RECEPTIVE FUELS. ANOTHER WINDY...HOT AND DRY DAY IS EXPECTED...BUT ISOLATED CONVECTION IS FORECAST TO START DEVELOPING OVER THE HIGHER TERRAIN BY LATE MORNING...AND OVER THE FAR EASTERN PLAINS TOMORROW AFN. ONE OR TWO OF THE STORMS OVER THE FAR SE CORNER WILL HAVE FAVORABLE SHEAR AND ENOUGH LLVL MOISTURE ON TAP TO BECOME STRONG. LOOK FOR MAX TEMPS ONCE AGAIN TO BE IN THE 90S FOR THE E PLAINS...AND MID TO UPPER 70S FOR THE HIGH VALLEYS. MOOR .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 247 PM MDT TUE JUN 17 2014 ...WETTER CONDITIONS POSSIBLE LATE WEEKEND INTO EARLY NEXT WEEK... ...ISOLD SVR THREAT POSSIBLE EARLY TOMORROW EVENING OVER FAR SE CO... STRONG SOUTHWEST FLOW ALOFT AT THE BEGINNING OF THIS PERIOD WILL GRADUALLY TRANSITION TO LIGHT WESTERLY FLOW AND THEN A VERY WEAK FLOW PATTERN BY EARLY NEXT WEEK. THIS PATTERN WILL SHOULD ALLOW FOR A WETTER PATTERN FOR THE REGION...ESPECIALLY LATE WEEKEND INTO EARLY NEXT WEEK. WED NITE... THERE IS A SLIGHT CHANCE THAT WE MAY SEE A STRONG STORM OVER THE FAR SE PLAINS ON THIS DAY AS THE DRYLINE WILL BE OVER THE REGION. MAIN CONCERN WILL BE STRONG GUSTY WINDS AND LIGHTNING WHICH WILL HAVE THE POTENTIAL TO CAUSE A GRASS FIRE DUE TO THE GUSTY SYNOPTIC S-SW WINDS. HOWEVER...I SHOULD NOTE...THAT THE LATEST 18Z NAM HINTS AT THE DRYLINE RETROGRADING BACK WEST OVER FAR SE CO. SFC WINDS SHIFT TO SOUTHEAST AND EHI AND STP RAPIDLY INCREASE ALONG THE CO/KS BORDER. THIS AREA WILL HAVE TO BE WATCHED CAREFULLY. LATE WED EVENING...A COOL FRONT WILL COME DOWN THE PLAINS. BEST CHANCE OF ANY POPS WITH THIS BOUNDARY WILL BE OVER THE E PLAINS...WHILE THE REST OF THE REGION SHOULD REMAIN DRY. THURSDAY... COOLER UPSLOPE FLOW WILL BE OVER THE REGION. HOWEVER...LLVL ATMOS WILL BE ON THE DRY SIDE SO NOT EXPECTING MUCH IN THE WAY OF ANY SIGNIFICANT CONVECTION. ANY CONVECTION THAT DEVELOPS WILL LIKELY BE LATE IN THE DAY OVER THE RATON MESA REGION AND MAYBE THE E SLOPES OF THE S MTNS. MAX TEMPS THU SHOULD BE ABOUT 4-8F COOLER ON THE PLAINS AS COMPARED TO WED MAXES. FRIDAY... WEAK DISTURBANCES ALOFT WILL MOVE OVER THE REGION AS THE FLOW ALOFT CONTINUES TO WEAKEN. OVERALL EXPECT IT TO REMAIN DRY...WITH ONLY ISOLD POPS OVER THE S MTNS AND POSSIBLY FAR E PLAINS. TEMPS WILL WARM BACK UP INTO THE U80S/L90S PLAINS. SATURDAY... LLVL MOISTURE WILL GRADUALLY INCREASE OVER THE PLAINS ON THIS DAY. EC IS MORE ROBUST WITH THIS MOISTURE THAN GFS...AND BREAKS OUT CONVECTION ALL AREAS...ESPECIALLY PALMER DVD REGION. MAX TEMPS SHOULD BE ABOUT A DEGREE OR TWO WARMER THAN FRI OVER THE PLAINS. SUNDAY... MOISTURE CONTINUES TO INCREASE OVER THE PLAINS AS CANADIAN HIGH PRESSURE BUILD SWD AND SEVERAL UPPER LVL DISTURBANCES MOVER OVER THE REGION IN THE WEAK ZONAL FLOW. MOISTURE MAY WORK A BIT FARTHER WEST INTO THE MTNS...ESPECIALLY C /MTNS AREA. ALL GUIDANCE HAS SOME HEALTHY QPF CONVECTIVE BULLSEYES OVER THE PLAINS...ESPECIALLY OVER THE PALMER DVD REGION. LIKEWISE...EXPECT A BETTER CHANCE OF SHOWERS AND STORMS OVER THE PLAINS ON THIS DAY WITH A BIT COOLER AFTERNOON TEMPS. WITH THE INCREASING MSTR AND WEAKER FLOW ALOFT...THE FLASH FLOOD THREAT OVER THE BURN SCARS WILL BE INCREASING. MONDAY AND TUESDAY... NOT MUCH CHANGE IN THE PATTERN AS FLOW ALOFT WILL BE FROM THE NW AND GENERALLY WEAK. SEVERAL DISTURBANCES WILL MOVE THROUGH THIS FLOW AND AFTERNOON AND EVENING ROUNDS OF CONVECTION ARE LIKELY OVER THE MTNS ADJ TO THE PLAINS...WITH THE CONVECTION MOVING INTO THE FAR E PLAINS DURING THE EVENING HOURS. TEMPS WILL BE ON THE COOL SIDE WITH THE CLOUDS AND MSTR OVER THE REGION. PERIODS OF HEAVY RAIN WILL BE POSSIBLE AND THE FLASH FLOOD CONCERNS WILL CONTINUE INTO EARLY NEXT WEEK OVER THE SCARS. OVERALL...THE INTERIOR MTNS WILL LIKELY REMAIN ON THE DRY SIDE DURING THIS PERIOD...WITH GRADUALLY INCREASING MSTR LATER IN THE PERIOD. THIS WILL ALLOW FOR THE INTERIOR MTNS TO CONTINUE TO DRY OUT WITH TIME. /HODANISH && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1117 PM MDT TUE JUN 17 2014 DRY SOUTHWEST FLOW WILL RESULT IN GENERALLY VFR THROUGH ABOUT 18Z WEDNESDAY. THEN...AN UPPER LEVEL DISTURBANCE WILL TRACK FROM WEST TO EAST ACROSS THE FORECAST AREA 18Z-06Z...TRIGGERING ISOLATED SHOWERS AND THUNDERSTORMS. MOISTURE WILL PRIMARILY BE HIGH BASED SO MAIN STORM THREATS WILL BE LIGHTNING AND GUSTY WINDS. HOWEVER...A FEW STORMS ACROSS THE FAR SOUTHEAST COLORADO PLAINS COULD BE STRONG OR SEVERE DUE TO BETTER MOISTURE. THESE STORMS COULD PRODUCE LARGE HAIL...WIND GUSTS OVER 60 MPH...LIGHTNING AND HEAVY RAIN. FORECAST MODELS GENERALLY AGREE THAT KCOS...KPUB AND KALS WILL GENERALLY BE VFR NEXT 24 HOURS. HOWEVER...THE PAST COUPLE RUNS OF THE NAM12 SUGGEST A BETTER CHANCE OF STORMS AT THESE SITES THAN THE OTHER MODELS. CONSEQUENTLY...CURRENT TAFS MAY NEED TO BE AMMENDED PENDING 12Z SOUNDING DATA AND MORNING MODEL RUNS. OTHER CONCERN TOMORROW WILL BE THE RETURN OF GUSTY SOUTHWEST WINDS 15 TO 30 MPH ACROSS THE AREA AFTER 16Z...WITH LOCALLY STRONGER GUSTS POSSIBLE...ESPECIALLY NEAR ANY CONVECTIVE ACTIVITY. LW && .FIRE WEATHER... ISSUED AT 855 PM MDT TUE JUN 17 2014 RED FLAG WARNING ALLOWED TO EXPIRE FOR TONIGHT. CONDITIONS HAVE SUBSIDED BELOW CRITICAL FIRE WEATHER LEVELS. && .PUB WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING FROM NOON TO 8 PM MDT WEDNESDAY FOR COZ222-226- 227. && $$ UPDATE...LW SHORT TERM...MOORE LONG TERM...HODANISH AVIATION...LW FIRE WEATHER...LW
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1114 PM MDT TUE JUN 17 2014 .UPDATE... ISSUED AT 712 PM MDT TUE JUN 17 2014 WITH THE FRONT HAVING MOVED INTO THE UINTA BASIN...UPDATED THE FORECAST FOR NORTHEAST UTAH. TEMPS IN EXTREME SW WYOMING HAS FALLEN INTO THE 30S WITH SNOW AT EVANSTON. REMOTE SENSORS IN DAGGETT COUNTY SHOWING TEMPS HAVE DROPPED INTO THE 30S. APPEARS TO BE A WET ROAD ON HWY 191 PER UDOT WEB CAM...BUT IF CURRENT TREND HOLDS...THEN SNOW IS ABOUT TO BEGIN AND UPDATED THE WSW TO REFLECT THIS. ELSEWHERE...THE RAP MODEL SHOWS THE BAROCLINIC ZONE WEAKENING AS THE FRONT MOVES ACROSS MOFFAT COUNTY IN NW COLORADO. THE SNOW OVER THE UINTA MOUNTAINS MAY NOT MAKE IT TO THE ELKHEADS OR PARK RANGE. CURRENT FORECAST TRENDS APPEAR ON TRACK AND NO OTHER UPDATES NEEDED. && .SHORT TERM...(TONIGHT THROUGH WEDNESDAY NIGHT) ISSUED AT 400 PM MDT TUE JUN 17 2014 STRONG SOUTHWEST WINDS OBSERVED ACROSS THE FORECAST AREA TODAY AHEAD OF COLD FRONT OVER NORTHEAST UTAH STRETCHING FROM EAST OF KRKS-KMLF AT 21Z. MAGNITUDE OF WINDS FROM 20 TO 30 MPH ACROSS MOST VALLEY LOCATIONS WITH GUSTS FROM 45 TO 50 MPH. SO FAR...NO CONVECTIVE ACTIVITY OUT AHEAD OF THE FRONT AS MOISTURE RELATIVELY LIMITED IN ADVANCE OF THE SYSTEM. NOCTURNAL COOLING WILL ALLOW WINDS TO DECOUPLE OVER THE VALLEYS LATER THIS EVENING BUT WILL CONTINUE TO BLOW PRETTY HARD UNTIL THEN SO WILL HOLD ONTO WIND ADVISORY THROUGH 9 PM. LATEST SHORT-RANGE MODELS INDICATED THE FRONT WILL PASS THROUGH KVEL AND INTO EXTREME NORTHWEST COLORADO BY 6 PM. EXPECT SHOWERS AND ISOLATED THUNDERSTORMS WILL BE CONFINED TO AREAS ALONG AND BEHIND THE FRONT SO CUT BACK POPS SOUTHEAST OF THE BOUNDARY THIS EVENING. SNOW LEVEL LOWERS RAPIDLY OVER THE EASTERN UINTAS BEHIND THE STRONG FRONT SO RAIN LOWER TO AROUND 8000 FEET STILL LOOKS REASONABLE. FRONT PROGGED TO CONTINUE SLOWLY SOUTHEAST THROUGH THE NIGHT REACHING ROUGHLY A KEGE TO KPGA LINE BY MORNING. AGAIN... PRECIPITATION CONFINED TO AREAS BEHIND THE FRONT WITH NORTHEAST UTAH AND THE NORTHWEST CORNER OF COLORADO FAVORED. LATEST NAM12 CONTINUED TO GENERATE DECENT ACCUMULATIONS OVER THE EASTERN UINTA MOUNTAINS FOR MID JUNE SO WILL CONTINUE WINTER WEATHER ADVISORY THROUGH MIDDAY WEDNESDAY. SHORTWAVE ROTATING THROUGH THE BASE OF THE TROUGH WILL DRIVE THE FRONT ACROSS THE REMAINDER OF THE FORECAST AREA WEDNESDAY AFTERNOON. PASSAGE OF THE WAVE CORRESPONDS WITH PEAK HEATING SO EXPECT GOOD SHOWER AND THUNDERSTORM COVERAGE OVER THE MOUNTAINS AND ADJACENT VALLEYS. COLDEST AIR STAYS NORTH SO SNOW LEVELS AT OR ABOVE 10K FEET AND LITTLE IMPACT ON HIGH PASSES EXPECTED. EMBEDDED THUNDERSTORMS COULD BRING DOWN STRONG WINDS ALOFT...BUT OTHERWISE LESS WINDY THAN TODAY. MUCH COOLER BEHIND THE FRONT WITH HIGHS DROPPING BY 10 TO 15 DEGREES FOR MOST AREAS. PRECIPITATION ENDS PRETTY ABRUPTLY WEDNESDAY EVENING AS SUBSIDENCE ...COOLING...AND DRYING WORK ACROSS THE AREA. CLEARING SKIES WILL LEAD TO SOME COLD OVERNIGHT LOWS. THUS FAR APPEARS ONLY PORTIONS OF NORTHWEST COLORADO UNDER THE THREAT OF LATE SEASON FREEZE WHICH COULD IMPACT SENSITIVE VEGETATION. THEREFORE...HOISTED A FREEZE WATCH FOR THE AREA FROM MIDNIGHT TO 9 AM THURSDAY MORNING. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 400 PM MDT TUE JUN 17 2014 A COOL THURSDAY MORNING WITH NEAR OR BELOW FREEZING TEMPERATURES IN SOME MOUNTAIN AREAS WILL EVOLVE INTO AN UNSEASONABLY COOL AFTERNOON... WITH HIGH TEMPERATURES IN THE VALLEYS STRUGGLING TO GET TO 80 DEGREES. HOWEVER...THROUGHOUT THE DAY WARMER AIR ALOFT WILL ADVECT INTO THE REGION AS THE UPPER LEVEL TROUGH EXITS AND RIDGING MOVES OVER EASTERN UTAH AND WESTERN COLORADO. HIGH PRESSURE WILL REMAIN OVERHEAD THROUGH EARLY NEXT WEEK ALLOWING TEMPERATURES TO REBOUND BACK TO AND ABOVE NORMAL. MOISTURE ALONG THE FRONT RANGE WILL REGRESS WEST TOWARD THE DIVIDE ON SUNDAY EVENING...BRINGING THE POSSIBILITY OF DIURNALLY DRIVEN MOUNTAIN CONVECTION ALONG THE CENTRAL MOUNTAINS SUNDAY THROUGH TUESDAY. ELSEWHERE WILL STAY DRY WITH LIGHT DIURNALLY DRIVEN WINDS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1111 PM MDT TUE JUN 17 2014 COLD FRONT WILL CONTINUE PUSHING ACROSS WESTERN COLORADO THROUGH EARLY WEDNESDAY MORNING...CROSSING THE DIVIDE BY 12Z. LOCAL SURFACE WIND OF G25-30KTS WILL CONTINUE THROGUH WEDNESDAY AFTERNOON. TURBULENCE WILL BE LESS...BUT STILL EXPECT SOME MODERATE CHOP. NE UTAH AND WRN COLORADO...SCT -SHRA/ISOLD -TSRA OVER NE UTAH WITH SNOW LEVEL LOWERING TO 8K FEET WILL SPREAD INTO NW COLORADO THIS MORNING. MOUNTAINS MAY BECOME OBSCURED AS THE FRONT CROSSES THE REGION. SCT -SHRA/ISOLD -TSRA WILL SPREAD ACROSS THE HIGHER TERRAIN OF WRN COLORADO BY 18Z WEDNESDAY. SHOWERS END WEDNESDAY EVENING WITH CLEARING SKIES. && .FIRE WEATHER... ISSUED AT 922 PM MDT TUE JUN 17 2014 THE RED FLAG WARNING FOR TODAY WAS ALLOWED TO EXPIRE AT 900 PM...THOUGH LOCALIZED POCKETS OF CRITICAL WIND/HUMIDITY MAY PERSIST FOR ANOTHER HOUR OR SO IN ZONES 203...290...292...207 AHEAD OF A COLD FRONT. HOWEVER...A RED FLAG WARNING REMAINS IN EFFECT FOR FIRE WEATHER ZONE 207 BELOW 9500 FEET ON WEDNESDAY BETWEEN NOON AND 700 PM FOR CONTINUE GUSTY WEST TO SOUTHWEST WINDS AND LOW HUMIDITY. THE COLD FRONT SHOULD EVENTUALLY CLEAR THE AREA WEDNESDAY EVENING...AND WINDS ARE EXPECTED TO DECREASE BEHIND THIS FRONTAL PASSAGE. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...RED FLAG WARNING FROM NOON TO 7 PM MDT WEDNESDAY FOR COZ207. FREEZE WATCH FROM LATE WEDNESDAY NIGHT THROUGH THURSDAY MORNING FOR COZ002. UT...WINTER WEATHER ADVISORY UNTIL NOON MDT WEDNESDAY FOR UTZ023. && $$ UPDATE...PF SHORT TERM...NL LONG TERM...JAM AVIATION...JDC FIRE WEATHER...JAD
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
410 AM EDT WED JUN 18 2014 .SYNOPSIS... 08Z WATER VAPOR AND H4 RAP ANALYSIS CONTINUE TO SHOW THE NORTHERN STREAM FLOW DIVING FAR TO THE SOUTH ACROSS THE INTER-MOUNTAIN WEST AROUND A WELL-DEFINED UPPER LOW SPINNING JUST TO THE NORTH OF THE GREAT BASIN. THIS FLOW THEN FLATTENS TO A MORE ZONAL CONFIGURATION DOWNSTREAM ACROSS THE UPPER MIDWEST/GREAT LAKES AND NORTHEAST. THE SYNOPTIC PATTERN ALOFT CLOSER TO HOME HAS NOT CHANGED MUCH IN THE PAST 24 HOURS AS THE FORECAST AREA REMAINS BETWEEN AN AREA OF UPPER RIDGING TO OUR NORTH AND NORTHWEST...AND A CLOSE LOW/TUTT FEATURE NEAR THE FLORIDA EAST COAST/BAHAMAS. THIS INITIAL IMPULSE IS FORECAST BY NWP TO RETROGRADE ACROSS THE PENINSULA TODAY FOLLOWED BY A SECOND IMPULSE MOVING INTO SOUTH FLORIDA ON THURSDAY. NEITHER OF THESE FEATURE WILL ADD MUCH IN THE WAY OF SYNOPTIC SUPPORT FOR LIFT...HOWEVER WHAT WILL BE ARRIVING IS A MUCH MORE MOIST COLUMN COMPARED TO WHAT WAS SEEN ON TUESDAY. WE DID SEE A SCATTERING OF STORMS TUESDAY...BUT THE DRY AIR EVENTUALLY WON THE OVERALL BATTLE AND KEPT COVERAGE DOWN. WE ARE UNLIKELY TO HAVE THIS PROBLEM LATER TODAY AS THE MOISTURE SURGES BACK IN FROM THE EAST AND SOUTHEAST AHEAD OF THE UPPER IMPULSE. AT THE SURFACE...SUBTROPICAL RIDGE AXIS REMAIN ALIGNED JUST TO THE NORTH OF THE I-10 CORRIDOR...SUPPLYING OUR ZONES WITH A SYNOPTIC EAST TO SOUTHEAST LOW LEVEL FLOW. REGIONAL RADARS SHOW THE FL PENINSULA ITSELF ON THE DRY SIDE EARLY THIS MORNING. ANY SHOWERS AND STORMS ARE WELL OFFSHORE INTO THE GULF ALONG THE STILL WESTWARD MOVING EAST COAST SEA-BREEZE/CONVECTIVE OUTFLOW FROM OUR STORMS THIS PAST EVENING. && .SHORT TERM (TODAY AND TONIGHT)... THE FORECAST WILL CALL FOR A QUIET MORNING GIVING WAY TO AN ACTIVE THUNDERSTORM REGIME BY THE SECOND HALF OF THE AFTERNOON/EVENING. SIMILAR TO TUESDAY...STRONGER EASTERLY FLOW JUST ABOVE THE SURFACE THIS AFTERNOON IS SHOWN BY ALL THE HIGH RESOLUTION GUIDANCE MEMBERS TO ESSENTIALLY PIN THE SEA-BREEZE AT OR NEAR THE COAST. THEREFORE STORM INITIATION FOR EACH AREA SHOULD BE MAINLY DEPENDENT ON THE ARRIVAL TIMING OF THE EAST COAST SEA-BREEZE BOUNDARY ALONG THE WEST COAST. GENERALLY SPEAKING THIS INTERACTION WILL OCCUR FIRST DOWN OVER OUR SOUTHERN ZONES...SO THE GREATEST COVERAGE OF STORMS WILL GET GOING SOUTH OF HILLSBOROUGH/POLK COUNTIES EARLY TO MID AFTERNOON...AND THEN EXPAND NORTHWARD FOR THE LATE AFTERNOON AND EARLY EVENING HOURS. THE E-SE FLOW REGIME IS A FAVORED REGIME FOR NUMEROUS STORMS ALONG THE I-75 CORRIDOR...AS LONG AS THERE ARE NOT ANY SIGNIFICANT NEGATIVE FACTORS IN THE COLUMN. DO NOT SEE MUCH TODAY IN TERMS OF NEGATIVES. MID-LEVEL THETAE VALUES WILL RETURN TO NEAR OR EVEN A BIT ABOVE CLIMO BY THE PEAK CONVECTION HOURS...SO THERE SHOULD NOT BE MUCH IN THE WAY OF ADVERSE DRY AIR ENTRAINMENT INTO THE UPDRAFT COLUMNS. THE MOISTURE PROFILES WILL BE MOST CONDUCIVE TO SUPPORT DEEP CONVECTION FROM TAMPA BAY SOUTHWARD. THE REALLY MOIST CONDITIONS WILL SIMPLY TAKE A BIT LONGER TO REACH PORTIONS OF THE NATURE COAST. THEREFORE RAIN CHANCES WILL SHOW NEAR CLIMO FOR EASTERLY FLOW OVER THE NATURE COAST...30-50%...INCREASING TO AROUND 60% THROUGH THE TAMPA BAY AREA...AND THEN CLOSER TO 70% DOWN ALONG THE I-75 CORRIDOR OF THE THE SUN COAST. FURTHER INLAND TO THE SOUTH OF THE I-4 CORRIDOR (THROUGH EASTERN POLK/HIGHLANDS COUNTIES) WILL ALSO TAPER POPS DOWN A BIT AS WE GET AWAY FROM THE GREATEST CONVERGENCE/FOCUS ASSOCIATED WITH THE COLLIDING SEA-BREEZES. OVERALL SETUP IS NOT ALL THAT FAVORABLE FOR WET MICROBURST PRODUCTION. ANY LOCALIZED WIND THREATS LATER TODAY WILL BE ASSOCIATED WITH PRECIPITATION LOADING OF CONVECTIVE COLUMNS...AND THIS TYPE OF PHENOMENA TENDS TO ONLY OCCUR WITH THE VERY STRONGEST STORMS...AS OPPOSED TO TRUE WET MICROBURSTS WHICH ARE MORE ENVIRONMENTALLY DRIVEN. STORM TOP DIVERGENCE ASSOCIATED WITH THE STRONGER CELLS WILL BE A BIG CLUE AS TO WHICH ONES MIGHT POSE A WIND THREAT UPON COLLAPSE. WHILE WE DO HAVE SOME DECENT FLOW IN THE COLUMN BELOW 10,000 FEET TODAY...ABOVE THIS LEVEL THE FLOW IS QUITE LIGHT...AND ALMOST VARIABLE IN NATURE. THIS TENDS TO SUGGEST THAT THE STORMS TODAY WILL BE SLOW MOVERS...CAPABLE OF SOME LOCALLY VERY HEAVY RAINFALL AMOUNTS. OK...ENOUGH ABOUT THE DIURNAL STORMS. LETS TALK ABOUT TEMPERATURES. THEY WILL BE SEASONABLE...WITHIN A COUPLE DEGREES OF 90 FOR HIGHS. BACK TO CONVECTION AGAIN. SLOW MOVING STORMS WEAKEN AND MIGRATE OFFSHORE DURING THE EVENING HOURS ONCE AGAIN SETTING UP A MAINLY DRY OVERNIGHT PERIOD. THE WEAK UPPER LEVEL SUPPORT OF THE PASSING TROUGH SHOULD BE ENOUGH TO KEEP SCT CONVECTION GOING ACROSS THE COASTAL WATERS THROUGH THE OVERNIGHT PERIOD. LIKELY THESE STORMS WILL STAY AWAY FROM THE BEACHES AS THE FOCUS PUSHES INTO THE GULF WITH THE SYNOPTIC EASTERLY FLOW/LAND BREEZE. HAVE A SPLENDID WEDNESDAY EVERYONE! && .MID TERM (THURSDAY AND FRIDAY)... UPPER LEVEL RIDGING SPRAWLS ACROSS THE GULF COASTAL AND SOUTHEASTERN STATES WHILE AN INVERTED TROUGH LINGERS ALOFT ROUGHLY THE SOUTHERN HALF OF FL. ATLANTIC HIGH PRESSURE RIDGING INITIALLY ALONG LATITUDE 30 WESTWARD TO THE CENTRAL GULF COAST SAGS DOWN ACROSS CENTRAL FL. OF THE LATEST GFS AND ECMWF...18/00Z...THE GFS SEEMS THE MORE AGGRESSIVE. THE GFS UPPER TROUGH IS MORE ROBUST THAN THE ECMWF. BOTH MODELS HAVE A SURFACE TROUGH/LOW OVER FL OR THE EAST GULF BUT THE GFS IS THE MORE PRONOUNCED WHILE THE ECMWF HAS A MORE TRANSITORY FEATURE. FOR THIS FORECAST HAVE FAVORED THE ECMWF. EXPECT ISOLATED TO SCATTERED STORMS WITH THE MOST COVERAGE INLAND IN THE AFTERNOONS AND EARLY EVENINGS...THEN SLIDING OUT OVER THE GULF. THE LOW LEVEL FLOW WILL BE LIGHT AS IT SHIFTS FROM EASTERLY TO SOUTHEASTERLY...EXCEPT FOR ONSHORE FLOW NEAR THE COAST IN AFTERNOON SEA BREEZES. .LONG TERM (SATURDAY THROUGH NEXT TUESDAY)... THE UPPER LEVEL TROUGHINESS WEAKENS OVER THE AREA THROUGH THE WEEK- END THEN GIVES WAY TO RIDGING BUILDING IN FROM THE ATLANTIC MON AND TUE. THE SURFACE RIDGE ACROSS CENTRAL FL DROPS DOWN TO BETWEEN THE KEYS AND CUBA LATE IN THE WEEKEND THEN SLOWLY LIFTS BACK NORTH...REACHING CENTRAL FL AGAIN BY LATE TUE. ADEQUATE MOISTURE WILL CONTINUE WITH ISOLATED TO SCATTERED (30-40 POPS) STORMS. LOW LEVEL FLOW BECOMES SOUTHWEST AND WESTERLY (AS THE SURFACE RIDGE MOVES SOUTH) FOR MUCH OF THE PERIOD WITH THE HIGHEST STORM COVERAGE IN THE EARLY TO MID AFTERNOONS AND INLAND. && .AVIATION... VFR CONDITIONS PREVAIL ACROSS THE REGION EARLY THIS MORNING AND ARE EXPECTED TO PREVAIL THROUGH THE MAJORITY OF THE TAF PERIOD. SCATTERED TO NUMEROUS THUNDERSTORMS IS EXPECTED TO DEVELOP DURING THE AFTERNOON AND EVENING HOURS. STORMS WILL LIKELY INITIATE EARLY/MID AFTERNOON DOWN TOWARD KFMY/KRSW AND THEN DEVELOP NORTHWARD THE REMAINDER OF THE AFTERNOON/EARLY EVENING. SOME OF THE STORMS ARE LIKELY TO BE STRONG...ESPECIALLY LATE IN THE DAY AND THEN THE ACTIVITY IS EXPECTED TO MIGRATE OFFSHORE AFTER 01-02Z. STORMS TODAY AS LIKELY TO BE SLOW MOVERS RESULTING IN LONGER THAN TYPICAL THUNDERSTORM ASSOCIATED RESTRICTION. && .MARINE... THE SUBTROPICAL RIDGE AXIS WILL REMAIN IN POSITION TO THE NORTH OF THE FORECAST WATERS THROUGH THE NEXT COUPLE OF DAYS. THIS POSITION WILL RESULT IN A GENERAL EAST TO SOUTHEAST FLOW ACROSS THE COASTAL WATERS. THE SEA BREEZE IS EXPECTED TO DEVELOP NEAR THE COAST EACH AFTERNOON AND TURN WINDS LOCALLY ONSHORE. WINDS BECOME MORE VARIABLE LATE IN THE WEEK AS THE POTENTIAL EXIST FOR A WEAK LOW OR TROUGH TO DEVELOP OVER THE EASTERN GULF. THE EASTERLY FLOW TODAY WILL PROMOTE THE POTENTIAL FOR RAPID THUNDERSTORM DEVELOPMENT LATE IN THE AFTERNOON AND EARLY EVENING ALONG THE COAST. MARINERS SHOULD REMAIN WEATHER AWARE...KEEPING AN EYE TOWARD THE EASTERN SKY FOR DEVELOPING STORMS. && .FIRE WEATHER... HIGH PRESSURE WILL REMAIN CENTERED TO THE NORTH OF THE FORECAST AREA THROUGH THE NEXT SEVERAL DAYS. A GENERAL EAST TO SOUTHEAST FLOW WILL KEEP ATLANTIC MOISTURE STREAMING INTO THE REGION AND PREVENT ANY CRITICAL LEVELS OF RELATIVE HUMIDITY. IN ADDITION...INCREASING MOISTURE ALOFT WILL COMBINE WITH THE EASTERLY FLOW TO RESULT IN AN ACTIVE THUNDERSTORM PATTERN THE NEXT SEVERAL AFTERNOON. THE ACTIVITY TODAY AND THURSDAY SHOULD BE MOST CONCENTRATED ALONG THE I-75 CORRIDOR DURING THE MIDDLE AFTERNOON HOUR AND INTO THE EVENING. THE SEA BREEZE IS EXPECTED TO BE PINNED CLOSE TO THE COAST THE NEXT COUPLE OF DAYS WITH LITTLE INLAND PROGRESSION. FOG POTENTIAL...A FEW POCKETS OF SHALLOW GROUND FOG ARE POSSIBLE EARLY THURSDAY MORNING...BUT NO SIGNIFICANT OCCURRENCES OF FOG ARE ANTICIPATED. && && .PRELIMINARY POINT TEMPS/POPS... TPA 90 75 89 74 / 60 40 30 20 FMY 90 73 89 72 / 70 20 40 30 GIF 91 72 88 72 / 50 20 40 20 SRQ 91 73 88 73 / 60 40 30 20 BKV 93 70 91 69 / 40 40 30 10 SPG 90 77 89 76 / 60 40 30 20 && .TBW WATCHES/WARNINGS/ADVISORIES... FL...NONE. GULF WATERS...NONE. && $$ SYNOPSIS/SHORT TERM/AVIATION/MARINE/FIRE WX...MROCZKA MID TERM/LONG TERM...RUDE
AREA FORECAST DISCUSSION...UPDATED
NWS MIAMI FL
147 AM EDT WED JUN 18 2014 .UPDATE... AN UPPER LEVEL LOW WILL CONTINUE OVER THE WESTERN ATLANTIC WATERS TODAY ALLOWING FOR TROPICAL MOISTURE TO CONTINUE TO WORK INTO SOUTH FLORIDA. SO WILL CONTINUE THE VCSH FOR THE EAST COAST TAF SITES THROUGH THE EARLY MORNING HOURS...BEFORE INTRODUCING VCTS FOR THE EAST COAST TAF SITES FOR THE DAY HOURS TODAY. THE WINDS WILL ALSO BE EASTERLY TODAY WITH SPEEDS AROUND 5 KNOTS THIS MORNING INCREASING TO 5 TO 10 KNOTS DURING THE DAY HOURS. FOR KAPF TAF SITE...THE WINDS WILL BE EASTERLY TODAY WITH SPEEDS AROUND 5 KNOTS THIS MORNING INCREASING TO 5 TO 10 KNOTS THIS AFTERNOON. THE KAPF TAF SITE WILL REMAIN DRY THROUGH THE EARLY MORNING HOURS BEFORE INTRODUCING VCSH FOR THE MORNING HOURS. VCTS WILL THEN BE ADDED FOR THE AFTERNOON HOURS AT KAPF TAF SITE. THE CEILING AND VIS WILL REMAIN IN VFR CONDITIONS TODAY FOR ALL OF THE TAF SITES ACROSS SOUTH FLORIDA...AS THE TIMING OF THE SHOWERS AND THUNDERSTORMS IS NOT KNOWN AT THIS TIME. LATER ON....A TEMPO WILL BE ADDED TO THE TAF SITES ACROSS SOUTH FLORIDA WHEN WE KNOW BETTER TIMING OF THE SHOWER AND THUNDERSTORM ACTIVITY. && .UPDATE...54/BNB .PREV DISCUSSION... /ISSUED 831 PM EDT TUE JUN 17 2014/ UPDATE... LATEST HIGH RESOLUTION MODELS ARE NOT INITIALIZING THE LARGE PRECIPITATION SHIELD ACROSS THE OFFSHORE ATLANTIC WATERS VERY WELL. LATEST RADAR TRENDS SHOW THIS SHIELD MOVING TO THE WEST- NORTHWEST VERY SLOWLY. MODERATE RAIN BANDS EMANATING OUT AHEAD ARE MOVING INTO EXTREME SOUTHERN MIAMI-DADE COUNTY. UPDATED POPS TO ACCOUNT FOR THE LATEST TRENDS. BELIEVE MOST OF THIS PRECIPITATION MAY LINGER THROUGH MUCH OF THE NIGHT BEING FED BY DEEP MOISTURE AND AN UPPER TROUGH DRAPED ACROSS THE AREA. && .PREV DISCUSSION... /ISSUED 754 PM EDT TUE JUN 17 2014/ AVIATION... LEFTOVER CONVECTION REMAINS ACROSS THE ATLANTIC WATERS EARLY THIS EVENING IN ASSOCIATION WITH AN UPPER LOW ACROSS THE AREA. THIS ACTIVITY IS SLOWLY PUSHING WEST-NORTHWEST BUT TENDS TO BE WEAKENING AS IT NEARS THE FLORIDA MAINLAND. HOWEVER...THERE IS STILL CONCERN THAT KMIA AND KTMB MAY BE AFFECTED OVER THE NEXT FEW HOURS. KEPT PRECIP MENTION OUT OF TAFS FOR NOW BUT WILL AMEND AS NECESSARY. && PREV DISCUSSION... /ISSUED 221 PM EDT TUE JUN 17 2014/ DISCUSSION... INTERESTING WEATHER PATTERN TODAY. THE UPPER LEVEL TROUGH HAS BROUGHT THE INSTABILITY EXPECTED. HOWEVER, THUNDERSTORMS THIS MORNING CAUSED AN OUTFLOW BOUNDARY THAT MOVED ACROSS SOUTH FLORIDA. AS IT DID, IT CAUSED THE DEVELOPMENT OF SHOWERS AND THUNDERSTORMS IN THE WESTERN HALF OF THE CWA. THIS FORMED A DONUT HOLE SHAPE OF PRECIPITATION THAT HAS KEPT MOST OF THE SHOWERS OUT OF THE MIAMI DADE AREA. LOOKING AT CURRENT RADAR IMAGERY, THE CONVECTION OVER THE ATLANTIC IS BEGINNING TO DISSIPATE AND THE LINE OVER THE GULF SIDE IS BEGINNING TO BE ENHANCED. HOWEVER, GIVEN THE CLOUD COVER AND CONDITIONS, EXPECT THE SHOWERS AND GENERAL THUNDERSTORMS TO BE THE RULE TODAY, WITH ONLY SLIGHT CHANCES OF STRONG THUNDERSTORMS DEVELOPING, AND THOSE SHOULD BE ON THE GULF SIDE. THIS PATTERN IS SHOWN FAIRLY WELL BY THE HRRR 15Z RUN. SEE NO REASON TO DISAGREE WITH THE MODELS SOLUTION FOR THIS AFTERNOON. HAVE HIGHER POPS ALONG THE GULF COAST AND STILL MAINTAINING LOW END CHANCE POPS FOR THE ATLANTIC COAST, EXCEPT FOR PALM BEACH, WHERE HIGH END CHANCE AS SHOWERS ARE STILL IN THAT AREA. ACTIVE WEATHER WILL CONTINUE THROUGH THE REMAINDER OF THE WEEK AS AN UPPER LEVEL LOW HANGS AROUND OVER THE FLORIDA PENINSULA. A SURFACE HIGH, TO THE NORTHEAST, WILL SLOWLY STRENGTHEN THIS WEEK AND CAUSE THE SFC WINDS TO FLUCTUATE BETWEEN SOUTHERLY AND EASTERLY. THIS WILL KEEP MUCH OF THE CONVECTION IN THE INTERIOR AND GULF COAST THIS WEEK, WITH SOME NOCTURNAL AND EARLY TO MID MORNING ACTIVITY ALONG THE ATLANTIC COAST EACH DAY. LONG TERM... THE HIGH OVER NORTHERN FLORIDA WILL START TO MOVE SOUTHWARD THIS WEEKEND...AS A TROUGH OF LOW PRESSURE DEVELOPS OVER THE EASTERN UNTIED STATES. THIS WILL ALLOW FOR THE STEERING FLOW TO BECOME MORE SOUTHERLY OVER SOUTH FLORIDA THIS WEEKEND FOCUSING THE HIGHEST POPS OVER THE LAKE OKEECHOBEE REGION. THE HIGH WILL CONTINUE TO MOVE SOUTH INTO THE FLORIDA STRAITS EARLY NEXT WEEK...AS THE TROUGH OF LOW PRESSURE CONTINUES TO BUILD INTO THE EASTERN UNITED STATES. THIS WILL ALLOW FOR THE STEERING FLOW TO BECOME MORE SOUTHWEST OVER SOUTH FLORIDA EARLY NEXT WEEK FOCUSING THE HIGHEST POPS OVER THE EASTERN AREAS OF SOUTH FLORIDA. MARINE... AN UPPER LEVEL LOW WILL KEEP CONVECTIVE ACTIVITY OVER ALL SOUTH FLORIDA WATERS THROUGH THE WEEK. A SURFACE HIGH TO THE NORTHEAST WILL KEEP AN EAST TO SOUTH SOUTHEAST FLOW ACROSS THE WATER FOR THE TIME BEING. SEA SHOULD BE 1 TO 3 FEET THROUGH THE WEEK FOR THE ATLANTIC WATERS, WITH THE GULF SEEING SEA OF 1 TO 2 FEET. CONDITIONS UNDER CONVECTIVE SHOWERS OR THUNDERSTORMS COULD BECOME ROUGH AT TIMES. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 75 84 74 89 / 30 50 20 40 FORT LAUDERDALE 76 84 75 89 / 30 50 20 30 MIAMI 76 85 75 90 / 30 50 20 40 NAPLES 73 86 73 89 / 50 50 20 40 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$ SHORT TERM...30/KOB LONG TERM....13/SI
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
404 AM CDT WED JUN 18 2014 .DISCUSSION... 307 AM CDT CONVECTIVE CHANCES REMAIN THE FOCUS THROUGH THE FORECAST PERIOD AS THE LARGE SCALE UPPER TROUGH PARKED OVER THE WESTERN U.S. SLOWLY EVOLVES THROUGH THE WEEKEND. EARLY MORNING WATER VAPOR IMAGERY SHOWS THIS LARGE UPPER LOW SPINNING OVER IDAHO WITH RIDGING JUST TO ITS EAST ACROSS THE MID MISSISSIPPI RIVER VALLEY INTO CENTRAL CANADA. NUMEROUS WAVES CONTINUE TO TRAVERSE THE LOWER AMPLITUDE PORTION OF THE RIDGE ACROSS THE PLAINS/MID AND UPPER MISSISSIPPI RIVER VALLEY SERVING TO FOCUS AREAS OF CONVECTION. ALSO OF NOTE IS A TROUGH THAT IS MOVING SOUTHWARD ACROSS ONTARIO AND QUEBEC. AT THE SURFACE...LOW PRESSURE IS IS PARKED OVER EASTERN COLORADO WITH A WARM FRONTAL BOUNDARY STRETCHING EASTWARD ACROSS SOUTHERN MINNESOTA AND CENTRAL WISCONSIN. IT THEN ARCS DOWN LAKE MICHIGAN AND EASTWARD TO ANOTHER SURFACE LOW OVER NORTHERN NEW YORK. TODAY AND TONIGHT...ANOTHER TOUGH FORECAST FOR TODAY WITH ONGOING CONVECTION AFFECTING HOW THINGS EVOLVE THROUGH THE DAY/EVENING. WARM FRONTAL BOUNDARY HAS LIFTED NORTH OF THE CWA EARLY THIS MORNING WITH MAIN CORRIDOR OF CONVECTION ALONG AND NORTH OF THE FRONT. THUNDERSTORM COMPLEX OVER NORTH CENTRAL IOWA HAS BECOME BETTER ORGANIZED AND HAS ACCELERATED EASTWARD. THE LOW LEVEL JET IS FOCUSED INTO NORTH CENTRAL IOWA BUT MOIST LOW/MID LEVEL FLOW TURNS MORE SOUTHWESTERLY TO THE EAST. 850-300 MB THICKNESS FIELDS DO SHOW A SOUTHEASTERLY COMPONENT WITH THE INSTABILITY GRADIENT ALSO ORIENTED A BIT NW-SE. PROGRESSION OF THIS COMPLEX WILL NEED TO BE WATCHED THE NEXT FEW HOURS AS A TURN TO THE SOUTHEAST IS SUGGESTED BY THE ABOVE ALONG WITH A TURNING OF FORWARD PROPAGATING CORFIDI VECTORS AFTER DAYBREAK. SHOULD THIS COMPLEX MAINTAIN ITSELF AND TURN MORE SOUTHEASTERLY THEN AT LEAST NORTHERN AREAS OF THE CWA WILL BE AFFECTED DURING THE MID/LATE MORNING HOURS. WOULD EXPECT THAT THE COMPLEX WOULD BE IN A DECAYING STATE AT THAT TIME BUT A STRONG COLD POOL SEEMS TO BE DEVELOPING AND UNSTABLE AIR WILL BE IN PLACE LOCALLY SO MAINTENANCE IS POSSIBLE. WILL GO AHEAD AND INDICATE HIGHER CHANCE POPS FOR THE NORTHERN THIRD TO HALF OF THE AREA LATE MORNING INTO MIDDAY BUT THESE WILL NEED TO BE TWEAKED BASED ON EVOLUTION OF THE COMPLEX THROUGH DAYBREAK. LOOKING TOWARDS THE AFTERNOON...WITH CONVECTION AFFECTING MUCH OF THE NEAR TERM GUIDANCE WILL CONTINUE TO APPROACH THE FORECAST FROM A LARGER SCALE PERSPECTIVE. THE UPPER TROUGH MOVING SOUTHWARD ACROSS CENTRAL ONTARIO LOOKS TO BECOME A KEY PLAYER IN OUR CONVECTIVE CHANCES LATER TODAY AND TONIGHT AS IT WILL BE DROPPING ACROSS THE LOWER GREAT LAKES WITH A STRONG SURFACE HIGH SPREADING SOUTHWARD AS WELL. THIS WILL PUSH THE STATIONARY BOUNDARY SOUTHWARD TO THE EAST WHILE THE UPPER TROUGH TO THE WEST PROGRESSES NORTHEAST ACROSS MONTANA PUSHING SOMEWHAT DISORGANIZED SURFACE LOW PRESSURE NORTHWARD. THIS WILL CAUSE THE BOUNDARY TO BECOME ORIENTED FROM NW TO SE INTO THE EVENING. THE SHIFTING OF THESE TROUGHS WILL ALLOW FOR THE UPPER RIDGE TO SHARPEN OVER THE MID-UPPER MISSISSIPPI RIVER VALLEY BUT IT IS WEAKER CLOSER TO THE LOCAL AREA SO SHORTWAVES MAY CONTINUE TO EMANATE THROUGH IT. WITH THE FRONTAL ZONE RE-ORIENTING THE LOCAL AREA LOOKS TO BE MORE SQUARELY PLACED WITHIN IT SUGGESTING THAT OUR CONVECTIVE CHANCES WILL INCREASE. MORNING CONVECTION WILL LIKELY DETERMINE HOW THINGS PLAY OUT THIS AFTERNOON AND PROBABLY LOWER EARLY AFTERNOON CHANCES ASSUMING THINGS STABILIZE FROM OUTFLOW OF THE COMPLEX TO THE NORTH OF IN THE WAKE OF CONVECTION CROSSING THE CWA...BUT THIS REMAINS TO BE SEEN. SEE BETTER LARGER SCALE POTENTIAL THIS EVENING AND OVERNIGHT AS THE FRONT SHIFTS SO WILL CARRY HIGHEST POPS DURING THAT TIME. IF CONVECTION STAYS NORTH THEN THERE SHOULD BE NO PROBLEM HAVING HIGH TEMPS REACH THE UPPER 80S AND LOWER 90S THIS AFTERNOON. MORNING/MIDDAY CONVECTION WOULD LIKELY RESULT IN LOWER TEMPS...THOUGH A LATE DAY RALLY IS POSSIBLE. LAKE BREEZE PROCESSES MAY COMBINE WITH THE SHIFTING FRONT TO BRING NORTHEAST WINDS TO LAKESHORE AREAS LATE THIS AFTERNOON BUT THIS MAY BE AFFECTED BY MORNING CONVECTION AS WELL. WILL HAVE EARLY HIGHS ALONG THE LAKE WITH A COOLING TREND DURING THE AFTERNOON. THURSDAY AND FRIDAY...THE UPPER LOW WILL MEANDER NORTH AND EAST INTO SOUTHERN ALBERTA WHILE THE UPPER TROUGH THAT IS OVER ONTARIO THIS MORNING CONTINUES SOUTHWARD INTO NEW ENGLAND. SURFACE HIGH PRESSURE WILL BE SETTLING INTO EASTERN ONTARIO AND WESTERN QUEBEC. POTENTIAL ONGOING CONVECTION WILL BE A DRIVER OF THINGS BUT SYNOPTICALLY SPEAKING THE WARM FRONT SHOULD BE ORIENTED MORE NORTHWEST TO SOUTHEAST. CONVECTIVE CHANCES WILL CONTINUE WITH THE BOUNDARY LIKELY TO BE IN THE AREA AS WELL AS A LIKELIHOOD OF WEAK UPPER IMPULSES TO MOVE THROUGH THE RIDGED FLOW OVERHEAD. WARM AND HUMID CONDITIONS WILL PERSIST SO ASSUMING CONVECTION IS NOT LIMITING TEMPS...UPPER 80S ARE EXPECTED...THOUGH A SOUTHEASTERLY WIND WILL COOL THE ILLINOIS LAKESHORE AREAS. BY FRIDAY...THE UPPER LOW WILL START TO MOVE TO THE EAST WITH A COOL FRONTAL BOUNDARY NOW STRETCHING SOUTHWARD FROM THE ASSOCIATED SURFACE LOW OVER THE FAR NORTHERN PLAINS/SOUTHERN CANADIAN PRAIRIES. THIS FRONT WILL PUSH EAST ACROSS THE AREA FRIDAY PERHAPS BRINGING A BETTER FOCUS FOR STORMS...THOUGH IT MAY CROSS EARLY IN THE DAY LIMITING THE POTENTIAL FOR NEW DEVELOPMENT. NOT EXPECTING MUCH CHANGE IN TEMPS/HUMIDITY BEHIND THE FRONT SO MID AND UPPER 80S WILL PROBABLY CONTINUE. SATURDAY AND BEYOND...THE UPPER LOW WILL DE-AMPLIFY OVER SOUTHERN MANITOBA INTO SATURDAY. THIS WILL LEAD TO A MORE ZONAL FLOW ACROSS MUCH OF THE CONUS. THIS WILL BE SUPPORTIVE OF WEAK SHORTWAVES MOVING THROUGH THE FLOW WHICH WILL LEAD TO MORE CHANCES FOR CONVECTION SATURDAY AND SUNDAY. ANOTHER UPPER TROUGH WILL MOVE SOUTHWARD INTO EASTERN CANADA LATER SUNDAY WHICH GUIDANCE CONTINUES TO PHASE WITH THE WEAKENED UPPER TROUGH ACROSS SOUTHERN CANADA. THE DEGREE OF PHASING CONTINUES TO VARY AMONG RUNS WHICH IS NOT SURPRISING GIVEN THE TIME RANGE AND WHAT NEEDS TO OCCUR PRIOR TO THAT TIME. WITH THIS TROUGH PASSING OVER OR TO THE NORTHEAST OF THE AREA MID LEVEL TEMPS WILL COOL EARLY NEXT WEEK...WITH COOLER AIR AND REDUCED HUMIDITY THANKS TO A NORTHEASTERLY LOW LEVEL FLOW. MDB && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 09Z... * PERIODIC CHANCES FOR THUNDERSTORMS THROUGH THE TAF PERIOD...BEST CHANCES SEEM TO BE WED MORNING...AND AGAIN MID/LATE WED AFTERNOON. BMD //DISCUSSION...UPDATED 06Z... A WARM FRONT LIES SOMEWHERE ACROSS CENTRAL WISCONSIN AND EXTENDS WEST ALONG THE IA/MN STATELINE. CONVECTION IS INCREASING IN COVERAGE ACROSS THE MID MISSOURI VALLEY AS LOW LEVEL JET RAMPS UP. WHILE THERE IS STRONG INSTABILITY IN PLACE LOCALLY...THERE IS STILL A CAP IN PLACE ACROSS ALL BUT FAR NORTHERN ILLINOIS WHERE A COUPLE THUNDERSTORMS HAVE DEVELOPED. OPTED TO REMOVE THUNDERSTORMS FOR THE OVERNIGHT HOURS AS IT SEEMS UNLIKELY THAT THE CONVECTION OVER IL/WI STATE LINE WILL INCREASE IN COVERAGE. THE AREA OVER IA/MN THOUGH MAY GROW UPSTREAM INTO A LINEAR COMPLEX AND WORK TOWARDS THE NORTHERN IL TERMINALS WEDNESDAY MORNING. CERTAINTY IN THIS HAPPENING IS LESS THAN 50% SO WILL NOT INCLUDE IN TAF AND WILL MONITOR TRENDS UPSTREAM OVERNIGHT. HOW CONVECTION WILL EVOLVE TOMORROW ALSO REMAINS UNCERTAIN. MODELS DO SUGGEST THAT THE CAP WILL ERODE MID AFTERNOON WITH THUNDERSTORMS POSSIBLE. WHERE EXACTLY WILL DEPEND ON HOW TONIGHT EVOLVES AND WHERE BOUNDARIES SET UP. WILL MAINTAIN A PROB30 FOR TSRA TOMORROW AFTERNOON FOR NOW. OUTSIDE OF THE INFLUENCE OF THUNDERSTORMS...VFR CONDITIONS AND SSW WINDS WILL PREVAIL UNTIL THE FRONT SAGS BACK SOUTH ACROSS THE AREA WEDNESDAY EVENING/NIGHT TURNING WINDS TO A MORE EASTERLY DIRECTION. BMD //ORD AND MDW CONFIDENCE...UPDATED 09Z... * LOW CONFIDENCE IN TSRA TIMING/PLACEMENT. * HIGH CONFIDENCE IN VFR CONDITIONS OUTSIDE OF THE INFLUENCE OF TSRA. BMD //OUTLOOK FOR ORD/MDW FOR 12Z THURSDAY-12Z TUESDAY...UPDATED 00Z... THURSDAY THROUGH MONDAY...GENERALLY VFR CONDITIONS WITH PERIODIC CHANCES FOR THUNDERSTORMS. KREIN && .MARINE... 247 AM CDT A FRONTAL BOUNDARY WILL LINGER IN THE VICINITY OF LAKE MICHIGAN THROUGH THE REMAINDER OF THE WEEK. IN GENERAL...SOUTH WINDS ARE EXPECTED SOUTH OF THE BOUNDARY WITH NORTHEAST WINDS NORTH OF THE BOUNDARY. THE FRONT IS EXPECTED TO SAG SOUTH ACROSS LAKE MICHIGAN TODAY...THEN LIFT BACK NORTH AGAIN THURSDAY INTO FRIDAY. HIGH PRESSURE WILL BUILD JUST EAST OF LAKE MICHIGAN LATE IN THE WEEK INTO THE WEEKEND AND SHOULD RESULT IN RELATIVELY MODEST WINDS ACROSS THE LAKE THIS WEEKEND INTO EARLY NEXT WEEK. BMD && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
  [top] Area Forecast Discussion National Weather Service Lincoln IL 331 AM CDT Wed Jun 18 2014 .DISCUSSION... ISSUED 330 AM CDT Wed Jun 18 2014 SHORT TERM...Today through Friday night Will issue another special weather statement to address the heat and humidity today and Thursday with highs around 90F and heat indices peaking from 95 to 100F similar to what we experienced yesterday. Strong upper level ridge (592 dm 500 mb high pressure over the southeast states) has been keeping much of central and southeast IL dry with the heat and humidity. MCS`s bringing more strong to severe thunderstorms with heavy rains north of IL over MN/WI and northern IA early this morning. These MCS`s forming on nose of low level jet interacting with frontal boundary drapped over southern great lakes and upper MS river valley and extends to 999 mb low pressure in NE CO. Strong 558 dm 500 mb low was along the ID/MT border with series of MCS east of it from SD into the southern great lakes. Upper level low near ID/MT border to lift ne into southern Sasketchewan by sunset Thu while short waves to weaken top of upper level ridge and increase chances of convection over central IL from north to south from this afternoon through next few days as frontal boundary sags back south toward central IL by Friday. Most areas will still be dry this morning with isolated convection developing in the tropical air mass this afternoon especially northern areas. RAP and HRRR models also show some qpf in far se IL from Lawrenceville se this afternoon. SPC has shifted slight risk of severe storms further south tonight to included most of central IL with just southern six counties not in slight risk. Highest risk of severe storms still appears north of Peoria where 30% risk of large hail and damaging wind gusts where best bulk shear in combination with moderate to strong instability. Highest convection chances of 50-60% over northern counties from tonight through Thu night shift further south during Friday with frontal boundary. SPC keeps slight risk nw of CWA Thu afternoon & Thu night especially over IA. LONG TERM...Saturday through Tuesday night Central IL gets into a wnw upper level flow during the weekend into early next week with disturbances tracking ese over top of ridge across the Midwest and interacting with a humid air mass to trigger daily chances of showers and thunderstorms. An upper level trof digging into the Midwest Monday afternoon and Monday night to drive a cold front se into IL Monday night and increase chances of showers and thunderstorms then with gradually cooler air by Tue. 07 && .AVIATION... ISSUED 1136 PM CDT Tue Jun 17 2014 VFR throughout, keeping some high clouds in the east this evening. Cu trend continues tomorrow, developing midday and SW winds 10-12kts, gusting to 20-25kts. Early morning convection across the nrn tier of the state progged to dip down into ILX, affecting the nrn terminals in the morning. Solutions are beginning to diverge even more, with more scattered activity. With coverage and timing all over the place, keeping the mention to VCTS tomorrow afternoon. LLWS is something to keep an eye on...from a speed shear perspective... but GFS, NAM, as well as the RAPP/RUC keeps winds under 35kts in the lowest 2kft. HJS && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
559 AM EDT WED JUN 18 2014 .SYNOPSIS... ISSUED AT 422 AM EDT WED JUN 18 2014 PERIODS OF SHOWERS AND THUNDERSTORMS WILL REMAIN POSSIBLE THROUGH THE NEXT SEVERAL DAYS AS A WEAK FRONTAL BOUNDARY SETS UP OVER THE SOUTHERN GREAT LAKES. THUNDERSTORMS ARE BEING AIDED BY VERY WARM AND HUMID AIRMASS CURRENTLY IN PLACE ACROSS THE REGION. HIGHS TODAY WILL BE IN THE UPPER 80S TO LOWER 90S WITH OVERNIGHT LOWS AROUND 70. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 422 AM EDT WED JUN 18 2014 ACTIVE WEATHER PATTERN CONTINUES FOR THE SOUTHERN GREAT LAKES AS SEVERAL CONVECTIVELY ENHANCED SHORTWAVES EJECT OUT OF WESTERN CONUS UPPER LOW AND TRAVEL ALONG QUASI-STATIONARY E-W FRONTAL BOUNDARY DRAPED THROUGH THE REGION. STRONG LLJ AHEAD OF THE MAIN TROUGH IS STILL MAINTAINING A CONTINUAL FEED OF VERY HIGH THETA-E AIR INTO THE MIDWEST AND OHIO VALLEY...SUPPORTING UNSTABLE CONDITIONS. SIMILAR TO THE PREVIOUS NIGHT...CONVECTION HAS FIRED UPSTREAM ON THE NOSE OF THE LLJ/MOISTURE CONVERGENCE AND HAS SLOWLY DRIFTED EASTWARD. THE DIFFERENCE IS THAT STORM CLUSTERS HAVE BEEN A LITTLE MORE DISCREET AND DISORGANIZED THUS FAR. UPSCALE GROWTH/ORGANIZATION LIKELY INHIBITED BY VERY STRONG CAPPING INVERSION NOTED ON 00Z KILX AND KDVN SOUNDINGS AS WELL AS A LACK OF ANY CLEAR SYNOPTIC SCALE SHORTWAVE/LINEAR FORCING. STORM CLUSTERS TO OUR NORTH AND NORTHWEST HAVE GRADUALLY FILLED IN/CONGLOMERATED DURING THE PAST FEW HOURS THOUGH...THANKS TO NOCTURNAL STRENGTHENING OF LLJ AND ASSOCIATED INCREASE IN LOW LEVEL MOISTURE AVAILABLE UPSTREAM. QUESTION IS HOW WILL THIS ACTIVITY EVOLVE THROUGH THE MORNING AND INTO THE AFTERNOON. LATEST SURFACE OBS ACTUALLY SHOW A FAIRLY PRONOUNCED TEMP AND MOISTURE GRADIENT JUST NORTH OF OUR CWA. ISENTROPIC ASCENT ALONG AND NORTH OF THIS SURFACE BOUNDARY IS DRIVING MUCH OF THE CURRENT CONVECTION WHILE ATMOSPHERE REMAINS CAPPED TO THE SOUTH. NOTHING TO FORCE THIS FRONT SOUTHWARD THROUGH THE MORNING WITH CONTINUAL SOUTHWEST FLOW/WAA AND NO ORGANIZED COLD POOLS/OUTFLOW BOUNDARIES AS OF YET. THEREFORE EXPECT OUR CWA WILL REMAIN LARGELY DRY DURING THIS PERIOD. SITUATION MAY CHANGE BY THE AFTERNOON AND EVENING. 00Z MODELS SUGGEST THAT A SUBTLE WAVE ASSOCIATED WITH CONVECTION CURRENTLY OVER FAR NW IA AND SOUTHERN MN WILL PUSH ESE BY LATER TODAY. SIMULTANEOUS SOUTHWARD PUSH OF CANADIAN ANTICYCLONE MAY FORCE THE FRONTAL BOUNDARY SOUTHWARD A BIT...WITH THE HELP OF COLD LAKES AND OUTFLOW FROM MORNING THUNDERSTORMS. MODELS INDICATE THIS WILL LIKELY BE ENOUGH TO WEAKEN THE STRONG CAP IN PLACE ACROSS OUR CWA AND ALLOW STORMS TO DEVELOP AND/OR PROPAGATE INTO OUR AREA BY THE AFTERNOON AND EVENING. LATEST HRRR AND HI-RES WRF-NMM ARE GENERALLY IN LINE WITH THIS IDEA. IF THE CAP DOES BREAK AS EXPECTED THEN SEVERE WEATHER WILL BE QUITE POSSIBLE. MODIFIED FORECAST SOUNDINGS INDICATE AROUND 3000 J/KG OF SBCAPE ACROSS THE AREA BY THE AFTERNOON. 0-6KM BULK SHEAR IS NOT AS HIGH SOUTH OF I-80 BUT SUFFICIENT FOR ORGANIZED LINE SEGMENTS/BOWS GIVEN LARGELY UNIDIRECTIONAL WIND FIELDS. LARGE HAIL AND STRONG WINDS WOULD BE THE PRIMARY THREATS WITH ANY STORMS THAT DO DEVELOP. THREAT FOR TORNADOES IS MUCH LOWER GIVEN LIMITED LOW LEVEL DIRECTIONAL SHEAR BUT CAN`T RULE IT OUT ENTIRELY. ALL OF THIS IS OF COURSE CONDITIONAL ON MORNING CONVECTIVE TRENDS AND GETTING ENOUGH SYNOPTIC SCALE ASCENT/COOLING TO ERODE THE STOUT 850-750MB INVERSION. CONFIDENCE IN THIS SCENARIO IS NOT HIGH ENOUGH TO SUPPORT LIKELY POPS JUST YET AND WILL HOLD WITH HIGH END CHANCES. THESE CHANCES WILL CONTINUE INTO THE OVERNIGHT PERIOD AS LLJ STRENGTHENS ONCE AGAIN AND POSSIBLY SUPPORTS PERSISTENT CONVECTION FOR OUR CWA IF SOUTHWARD PUSH OF FRONTAL BOUNDARY MATERIALIZES. && .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 422 AM EDT WED JUN 18 2014 LITTLE SUBSTANTIVE CHANGE TO LONG TERM PERIOD. EXPECT PRODIGIOUS CONVECTION SPAWNING ALONG/DOWNSTREAM OF INTENSE INTERMOUNTAIN MID TROPOSPHERIC VORTEX TO CONTINUE INTO THIS WEEKEND. ACTIVE PATTERN WITH CONTINUATION OF CONVECTIVE INDUCED MESOVORTICIES AFFORDING TO INITIATE/RENEW TSRA ALONG/NORTH OF SURFACE FRONTAL BOUNDARY THAT PRESENTLY EXTENDS FROM NORTHERN NE TO CENTRAL WI THEN SOUTHEASTWARD THROUGH THE SOUTHERN GREAT LAKES REGION. WHILE STRONGEST INSTABILITY AND MORE SIGNIFICANT FOCUS FOR INITIATION REMAINS UPSTREAM OF CWA ON THU...HAVE CONTD CHC POP MENTION/HIGHEST IN SOUTHWEST CWA AS NORTHERN ONTARIO ANTICYCLONE SHIFTS SEWD AND ASSERTS RIDGING SOUTHWARD THROUGH LAKE HURON INTO NWRN OH...SHUNTING CONVECTIVE MAINTENANCE FARTHER SOUTH AS IT PROGRESSES DOWNSTREAM. FRIDAY PRESENTS EVEN HIGHER POTENTIAL FOR MORE WIDESPREAD CONVECTION AS LOBE OF SIGNIFICANT 30-50M/12 HR MID LEVEL HEIGHT FALLS PEELS THROUGH WESTERN GREAT LAKES AS PRIMARY UPSTREAM VORTEX BIFURCATES DOWNSTREAM RIDGE TO BECOME REXED ACROSS SOUTHERN MANITOBA. MID 80S/NEAR 70 SURFACE CONDITIONS YIELD MODERATE INSTABILITY 2500-3500 J/KG SBCAPE AND MODEST DEEP LAYER SHEAR. DIFFERENTIATED FRIDAY WITH LIKELY POPS SANS TIMING GIVEN BETTER SIGNALS AMID RICH THETA-E REGIME FIRMLY IN PLACE. THEREAFTER INCREASING MODEL DIVERGENCE NOTED WITH DEVOLUTION OF REXED SYSTEM WITH ECMWF/GEM MAINTAINING ORPHANED TROFFING ACROSS NORTHERN GREAT LAKES INTO NORTHERN PLAINS INTO NEXT WEEK AND GFS ESPECIALLY BTWN ECMWF AND GEM VS GFS RELEASE DOWNSTREAM THROUGH THE LOWER GREAT LAKES DYS5/6. POSSIBLE LULL SATURDAY THOUGH HIGHLY CONTINGENT ON FRIDAY CONVECTION LEADING TO SUBSTANTIAL OVERTURNING AND FAR SOUTHWARD BOUNDARY SHUNT. AT THIS TIME LOW CHANCE MENTION REMAINS GIVEN HIGH CONDITIONALITY. TREND DRY MONDAY NIGHT/TUESDAY AS DEEPER NORTH/NORTHEAST FLOW PER NORTHERN GREAT && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING) ISSUED AT 558 AM EDT WED JUN 18 2014 WIDESPREAD THUNDERSTORMS HAVE DEVELOPED ALONG AND NORTH OF A WARM FRONT CURRENTLY STRETCHED FROM SOUTHERN MICHIGAN THROUGH NORTHERN IOWA WITH DRY AND CAPPED CONDITIONS SOUTH OF THAT FRONT IN OUR AREA. FRONT EXPECTED TO RETREAT SOUTHWARD LATER TODAY THOUGH AS SHORTWAVE TROUGH PASSES THROUGH THE REGION. THIS WILL LIKELY WEAKEN THE CAP AND ALLOW THUNDERSTORMS TO DEVELOP AND/OR PROPAGATE INTO NORTHERN INDIANA. SEVERAL HI-RES MODELS SUPPORT THIS SCENARIO BUT DISAGREE ON EXACT TIMING. FOR NOW THINK THE BEST CHANCE WILL BE AFTER 16Z AT KSBN AND AFTER 18Z AT KFWA. SCATTERED CONVECTION WILL LIKELY LINGER THROUGH THE OVERNIGHT PERIOD AS LLJ RAMPS UP ONCE AGAIN. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ SYNOPSIS...AGD SHORT TERM...AGD LONG TERM...MURPHY AVIATION...AGD VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.NORTHERNIN.GOV WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
422 AM EDT WED JUN 18 2014 .SYNOPSIS... ISSUED AT 422 AM EDT WED JUN 18 2014 PERIODS OF SHOWERS AND THUNDERSTORMS WILL REMAIN POSSIBLE THROUGH THE NEXT SEVERAL DAYS AS A WEAK FRONTAL BOUNDARY SETS UP OVER THE SOUTHERN GREAT LAKES. THUNDERSTORMS ARE BEING AIDED BY VERY WARM AND HUMID AIRMASS CURRENTLY IN PLACE ACROSS THE REGION. HIGHS TODAY WILL BE IN THE UPPER 80S TO LOWER 90S WITH OVERNIGHT LOWS AROUND 70. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 422 AM EDT WED JUN 18 2014 ACTIVE WEATHER PATTERN CONTINUES FOR THE SOUTHERN GREAT LAKES AS SEVERAL CONVECTIVELY ENHANCED SHORTWAVES EJECT OUT OF WESTERN CONUS UPPER LOW AND TRAVEL ALONG QUASI-STATIONARY E-W FRONTAL BOUNDARY DRAPED THROUGH THE REGION. STRONG LLJ AHEAD OF THE MAIN TROUGH IS STILL MAINTAINING A CONTINUAL FEED OF VERY HIGH THETA-E AIR INTO THE MIDWEST AND OHIO VALLEY...SUPPORTING UNSTABLE CONDITIONS. SIMILAR TO THE PREVIOUS NIGHT...CONVECTION HAS FIRED UPSTREAM ON THE NOSE OF THE LLJ/MOISTURE CONVERGENCE AND HAS SLOWLY DRIFTED EASTWARD. THE DIFFERENCE IS THAT STORM CLUSTERS HAVE BEEN A LITTLE MORE DISCREET AND DISORGANIZED THUS FAR. UPSCALE GROWTH/ORGANIZATION LIKELY INHIBITED BY VERY STRONG CAPPING INVERSION NOTED ON 00Z KILX AND KDVN SOUNDINGS AS WELL AS A LACK OF ANY CLEAR SYNOPTIC SCALE SHORTWAVE/LINEAR FORCING. STORM CLUSTERS TO OUR NORTH AND NORTHWEST HAVE GRADUALLY FILLED IN/CONGLOMERATED DURING THE PAST FEW HOURS THOUGH...THANKS TO NOCTURNAL STRENGTHENING OF LLJ AND ASSOCIATED INCREASE IN LOW LEVEL MOISTURE AVAILABLE UPSTREAM. QUESTION IS HOW WILL THIS ACTIVITY EVOLVE THROUGH THE MORNING AND INTO THE AFTERNOON. LATEST SURFACE OBS ACTUALLY SHOW A FAIRLY PRONOUNCED TEMP AND MOISTURE GRADIENT JUST NORTH OF OUR CWA. ISENTROPIC ASCENT ALONG AND NORTH OF THIS SURFACE BOUNDARY IS DRIVING MUCH OF THE CURRENT CONVECTION WHILE ATMOSPHERE REMAINS CAPPED TO THE SOUTH. NOTHING TO FORCE THIS FRONT SOUTHWARD THROUGH THE MORNING WITH CONTINUAL SOUTHWEST FLOW/WAA AND NO ORGANIZED COLD POOLS/OUTFLOW BOUNDARIES AS OF YET. THEREFORE EXPECT OUR CWA WILL REMAIN LARGELY DRY DURING THIS PERIOD. SITUATION MAY CHANGE BY THE AFTERNOON AND EVENING. 00Z MODELS SUGGEST THAT A SUBTLE WAVE ASSOCIATED WITH CONVECTION CURRENTLY OVER FAR NW IA AND SOUTHERN MN WILL PUSH ESE BY LATER TODAY. SIMULTANEOUS SOUTHWARD PUSH OF CANADIAN ANTICYCLONE MAY FORCE THE FRONTAL BOUNDARY SOUTHWARD A BIT...WITH THE HELP OF COLD LAKES AND OUTFLOW FROM MORNING THUNDERSTORMS. MODELS INDICATE THIS WILL LIKELY BE ENOUGH TO WEAKEN THE STRONG CAP IN PLACE ACROSS OUR CWA AND ALLOW STORMS TO DEVELOP AND/OR PROPAGATE INTO OUR AREA BY THE AFTERNOON AND EVENING. LATEST HRRR AND HI-RES WRF-NMM ARE GENERALLY IN LINE WITH THIS IDEA. IF THE CAP DOES BREAK AS EXPECTED THEN SEVERE WEATHER WILL BE QUITE POSSIBLE. MODIFIED FORECAST SOUNDINGS INDICATE AROUND 3000 J/KG OF SBCAPE ACROSS THE AREA BY THE AFTERNOON. 0-6KM BULK SHEAR IS NOT AS HIGH SOUTH OF I-80 BUT SUFFICIENT FOR ORGANIZED LINE SEGMENTS/BOWS GIVEN LARGELY UNIDIRECTIONAL WIND FIELDS. LARGE HAIL AND STRONG WINDS WOULD BE THE PRIMARY THREATS WITH ANY STORMS THAT DO DEVELOP. THREAT FOR TORNADOES IS MUCH LOWER GIVEN LIMITED LOW LEVEL DIRECTIONAL SHEAR BUT CAN`T RULE IT OUT ENTIRELY. ALL OF THIS IS OF COURSE CONDITIONAL ON MORNING CONVECTIVE TRENDS AND GETTING ENOUGH SYNOPTIC SCALE ASCENT/COOLING TO ERODE THE STOUT 850-750MB INVERSION. CONFIDENCE IN THIS SCENARIO IS NOT HIGH ENOUGH TO SUPPORT LIKELY POPS JUST YET AND WILL HOLD WITH HIGH END CHANCES. THESE CHANCES WILL CONTINUE INTO THE OVERNIGHT PERIOD AS LLJ STRENGTHENS ONCE AGAIN AND POSSIBLY SUPPORTS PERSISTENT CONVECTION FOR OUR CWA IF SOUTHWARD PUSH OF FRONTAL BOUNDARY MATERIALIZES. && .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 422 AM EDT WED JUN 18 2014 LITTLE SUBSTANTIVE CHANGE TO LONG TERM PERIOD. EXPECT PRODIGIOUS CONVECTION SPAWNING ALONG/DOWNSTREAM OF INTENSE INTERMOUNTAIN MID TROPOSPHERIC VORTEX TO CONTINUE INTO THIS WEEKEND. ACTIVE PATTERN WITH CONTINUATION OF CONVECTIVE INDUCED MESOVORTICIES AFFORDING TO INITIATE/RENEW TSRA ALONG/NORTH OF SURFACE FRONTAL BOUNDARY THAT PRESENTLY EXTENDS FROM NORTHERN NE TO CENTRAL WI THEN SOUTHEASTWARD THROUGH THE SOUTHERN GREAT LAKES REGION. WHILE STRONGEST INSTABILITY AND MORE SIGNIFICANT FOCUS FOR INITIATION REMAINS UPSTREAM OF CWA ON THU...HAVE CONTD CHC POP MENTION/HIGHEST IN SOUTHWEST CWA AS NORTHERN ONTARIO ANTICYCLONE SHIFTS SEWD AND ASSERTS RIDGING SOUTHWARD THROUGH LAKE HURON INTO NWRN OH...SHUNTING CONVECTIVE MAINTENANCE FARTHER SOUTH AS IT PROGRESSES DOWNSTREAM. FRIDAY PRESENTS EVEN HIGHER POTENTIAL FOR MORE WIDESPREAD CONVECTION AS LOBE OF SIGNIFICANT 30-50M/12 HR MID LEVEL HEIGHT FALLS PEELS THROUGH WESTERN GREAT LAKES AS PRIMARY UPSTREAM VORTEX BIFURCATES DOWNSTREAM RIDGE TO BECOME REXED ACROSS SOUTHERN MANITOBA. MID 80S/NEAR 70 SURFACE CONDITIONS YIELD MODERATE INSTABILITY 2500-3500 J/KG SBCAPE AND MODEST DEEP LAYER SHEAR. DIFFERENTIATED FRIDAY WITH LIKELY POPS SANS TIMING GIVEN BETTER SIGNALS AMID RICH THETA-E REGIME FIRMLY IN PLACE. THEREAFTER INCREASING MODEL DIVERGENCE NOTED WITH DEVOLUTION OF REXED SYSTEM WITH ECMWF/GEM MAINTAINING ORPHANED TROFFING ACROSS NORTHERN GREAT LAKES INTO NORTHERN PLAINS INTO NEXT WEEK AND GFS ESPECIALLY BTWN ECMWF AND GEM VS GFS RELEASE DOWNSTREAM THROUGH THE LOWER GREAT LAKES DYS5/6. POSSIBLE LULL SATURDAY THOUGH HIGHLY CONTINGENT ON FRIDAY CONVECTION LEADING TO SUBSTANTIAL OVERTURNING AND FAR SOUTHWARD BOUNDARY SHUNT. AT THIS TIME LOW CHANCE MENTION REMAINS GIVEN HIGH CONDITIONALITY. TREND DRY MONDAY NIGHT/TUESDAY AS DEEPER NORTH/NORTHEAST FLOW PER NORTHERN GREAT LAKES SURFACE RIDGING SHOULD FINALLY AFFORD DRIER/SUBSIDENT REGIME. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 138 AM EDT WED JUN 18 2014 CONVECTION CURRENTLY DEVELOPING ALONG AND NORTH OF STATIONARY FRONT OVER SOUTHERN WISCONSIN AND LAKE MICHIGAN AS LLJ INCREASES AND ADVECTS BETTER MOISTURE INTO THE REGION. STRONG CAPPING INVERSION HAS LIMITED UPSCALE GROWTH SO FAR THIS EVENING BUT EXPECT THUNDERSTORMS TO EXPAND ALONG THE FRONT BY LATER TONIGHT. THIS FRONT LOOKS TO REMAIN NORTH OF THE TERMINALS THOUGH AND HI- RES MODELS KEEP BULK OF THE CONVECTION NORTH OF THE AREA THROUGH LATE MORNING. HAVE THEREFORE KEPT THE TAFS DRY/VFR THROUGH THE THIS PERIOD. AFTERNOON MAY BE A DIFFERENT STORY AS MODELS SUGGEST WEAK SHORTWAVE WILL ENTER THE REGION AND CAPITALIZE ON HIGHLY UNSTABLE ENVIRONMENT. CHANCES FOR THUNDERSTORMS WILL INCREASE BEGINNING AROUND 18Z BUT CONFIDENCE IN TIMING AND LOCATION IS TOO LOW FOR INCLUSION IN THE TAFS AT THIS TIME. WILL FINISH COMBING THROUGH THE 00Z DATA AND ATTEMPT TO NAIL DOWN DETAILS WITH THE 12Z ISSUANCE. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ SYNOPSIS...AGD SHORT TERM...AGD LONG TERM...MURPHY AVIATION...AGD VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.NORTHERNIN.GOV WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1058 PM MDT TUE JUN 17 2014 .UPDATE... ISSUED AT 948 PM MDT TUE JUN 17 2014 NO MAJOR CHANGES MADE FOR THIS EVENING ALTHOUGH DID ADJUST DEWPOINTS UP CONSIDERABLY IN THE FAR EAST AS DRYLINE BEGINS TO REGRESS SLOWLY WESTWARD. LATEST NAM AND PREVIOUS GFS SHOW A MID-LEVEL SHORT WAVE TROUGH WILL LIFT OUT OF THE MAIN WESTERN U.S. UPPER LOW OVERNIGHT WITH AN ATTENDANT SURFACE LOW MOVING FROM COLORADO INTO NEBRASKA. THIS WILL TEND TO CHANGE SURFACE WINDS BACK TO THE SOUTHWEST BY LATER TONIGHT AND HALT THE WESTWARD PROGRESSION OF HIGHER DEWPOINTS. STILL A BIT OF UNCERTAINTY FOR TOMORROW AS TO WHERE DRYLINE WILL EVENTUALLY END UP WEDNESDAY AFTERNOON. NAM CONTINUES TO INDICATE POSSIBLE STORM DEVELOPMENT ON THE DRYLINE IN OUR EASTERN COUNTIES DURING THE AFTERNOON AND THEN ANOTHER SHOT AT STORMS MOVING EAST OUT OF COLORADO ASSOCIATED WITH THE UPPER TROUGH DURING THE EVENING. FORECAST CAPE DOESNT LOOK ALL THAT IMPRESSIVE RIGHT NOW FOR MAJOR SEVERE WITH THE EVENING STORMS. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 135 PM MDT TUE JUN 17 2014 LATEST WV IMAGERY AND RAP ANALYSIS SHOW SW FLOW CONTINUING ACROSS THE PLAINS WITH A LARGE CLOSED UPPER LOW OVER IDAHO. VERY DRY AIR CONTINUES TO ADVECT NORTHEAST WITHIN THE FLOW ALOFT INTO THE PLAINS WITH MONSOONAL SHOWERS/THUNDERSTORMS OVER THE HIGHER TERRAIN IN THE SOUTHERN ROCKIES. SURFACE LOW PRESSURE IS CURRENTLY IN PLACE OVER OUR CWA WITH THE STRONGEST PRESSURE GRADIENT WELL EAST OF OUR AREA. A DRY LINE IS ALSO EXTENDS FROM JUST EAST OF OBERLIN KANSAS AND OVER SOUTHWEST KANSAS. FOR THIS AFTERNOON AND EVENING...WHILE SHORT RANGE GUIDANCE IS SHOWING ISOLATED THUNDERSTORM ACTIVITY DEVELOP OVER THE NE PANHANDLE...A VERY DEEP/DRY AIR MASS IN PLACE OVER OUR CWA AND A TREND TOWARDS LOW TD VALUES MIXING NORTH SHOULD PRECLUDE ANY THUNDERSTORM CHANCES. IT STILL LOOKS LIKE WE COULD HAVE A PERIOD OF GUSTY WINDS THIS AFTERNOON BASED ON SHORT RANGE GUIDANCE...THIS DOESNT LOOK LIKE IT WILL BE WIDESPREAD AND SURFACE PATTERN/GRADIENT IS FAIRLY WEAK OVER OUR CWA. RH VALUES HAVE DECREASED SIGNIFICANTLY HOWEVER WITH FUELS STILL QUESTIONABLE AND WINDS MARGINAL NO RED FLAG WARNING IS PLANNED THIS AFTERNOON. WEDNESDAY...WHILE STILL ABOVE NORMAL HIGH TEMPERATURES SHOULD BE COOLER THAN THE LAST FEW DAYS AS THE AIR MASS ALOFT BEGINS TO CHANGE WITH APPROACHING UPPER TROUGH AND APPROACHING COLD FRONT. WE COULD START TO SEE ISOLATED TO WIDELY SCATTERED THUNDERSTORMS DEVELOPING ALONG A CONVERGENCE ZONE IN OUR EASTERN CWA BY LATE AFTERNOON WITH BETTER COVERAGE AFTER 00Z (7PM CDT). SEVERE THREAT WILL BE LIMITED WED AFTERNOON DUE TO QUESTIONABLE THUNDERSTORM COVERAGE AND LIMITED SHEER. HOWEVER...DEPENDING ON THE LOCATION OF TROUGH AXIS WE COULD SEE MODERATE INSTABILITY AND STEEP LAPSE RATES IN PLACE OVER THE EASTERN CWA THAT COULD SUPPORT AN ISOLATED HAIL/DAMAGING WIND THREAT THROUGH WED AFTERNOON. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 247 PM MDT TUE JUN 17 2014 WEDNESDAY EVENING AN UPPER LEVEL SHORT WAVE TROUGH WILL MOVE OVER THE TRI-STATE AREA AHEAD OF THE MAIN TROUGH WHICH WILL MOVE THROUGH DURING THE EVENING/OVERNIGHT HOURS. AS THE MAIN TROUGH MOVES THROUGH...700-300MB FRONTOGENESIS INCREASES OVER THE NORTHERN HALF OF THE AREA. LOW LEVEL MIXING RATIOS...SPECIFICALLY THOSE AT 750MB...INCREASE AHEAD OF THE MAIN TROUGH AS THE TROUGH MOVES THROUGH. AT THE SURFACE THE DRY LINE OVER NORTON AND GRAHAM COUNTIES WILL MOVE BACK WEST ONE OR TWO TIERS OF COUNTIES AS THE SURFACE LOW OVER EASTERN COLORADO DEEPENS. LOW LEVEL MOISTURE WILL ALSO INCREASE OVER THE EASTERN PART OF THE AREA EAST OF RETREATING DRY LINE. IN ADDITION A COLD FRONT WILL BEGIN TO ADVANCE SOUTHEAST ACROSS THE AREA AS THE SURFACE LOW DEEPENS. AS IT MOVES SOUTHEAST RAPID PRESSURE RISES WILL ACCOMPANY THE FRONT AND THE LOW LEVEL JET WILL STRENGTHEN TO NEAR 50 KTS JUST BEHIND THE FRONTAL BOUNDARY. WINDS WILL LIKELY GUST TO 45 MPH BEHIND THE FRONT. DURING THE OVERNIGHT HOURS THE ISALLOBARIC TREND DECLINES SO WINDS SHOULD NOT BE AS STRONG AS THE FRONT CONTINUES TO MOVE THROUGH...EXITING THE AREA AROUND SUNRISE. MEANWHILE THE MAIN UPPER LEVEL TROUGH WILL DEEPEN OVER THE AREA AROUND MIDNIGHT. AHEAD OF IT TEMPERATURE LAPSE RATES ABOVE 850 TO 750 MB OR SO STEEPEN. THE ADDED EFFECT OF INCREASED LOW LEVEL MIXING RATIOS WILL CREATE ELEVATED CAPE OF 1000-2500 J/KG...WITH THE HIGHEST CAPE OVER FAR EASTERN NORTON AND GRAHAM COUNTIES. 0-6KM BULK SHEAR IS AROUND 50KTS SO SEVERE THUNDERSTORMS WILL BE LIKELY. TRIED TO HIGHLIGHT THE MOST LIKELY TIME/LOCATION OF THE SEVERE STORMS IN THE FORECAST. THIS SETUP IS SIMILAR TO SATURDAY EVENING AS FAR AS A SEVERE WIND POTENTIAL WITH STORMS FORMING UPSTREAM OF A COLD FRONT WITH STRONG ISALLOBARIC TRENDS. WOULD NOT BE SURPRISED IF STORMS MERGE INTO A SQUALL LINE BEHIND THE FRONT AND IF HIGH WINDS DEVELOP BEHIND THE STORMS SIMILAR TO SATURDAY NIGHT. TOWARD SUNRISE THE UPPER LEVEL TROUGH MOVES NORTHEAST OF THE AREA WITH DRIER MORE STABLE AIR FOLLOWING THE COLD FRONT IN FROM THE WEST. THURSDAY WILL BE COOLER AND DRY DUE TO A CAPPED ENVIRONMENT. THURSDAY LATE AFTERNOON/EVENING A WEAKER 500MB SHORT WAVE TROUGH DEVELOPS OVER THE COLORADO BORDER. THE DRY LINE/COLD FRONT WILL RETREAT BACK INTO THE FAR SOUTHEAST PART OF THE AREA AS THE LEE TROUGH OVER SOUTHEAST COLORADO DEEPENS. THIS WILL ALLOW LOW LEVEL MIXING RATIOS TO INCREASE EAST OF THE SURFACE BOUNDARY AND ALLOW ELEVATED CAPE TO DEVELOP AHEAD OF THE 500MB TROUGH. AS A RESULT WILL HAVE SOME LOW RAINFALL CHANCES FOR STORMS AHEAD OF THE TROUGH. AS THE NIGHT PROGRESSES THE SURFACE BOUNDARY WILL MOVE NORTH FOLLOWING THE RETREATING UPPER LEVEL TROUGH. DUE TO SOUNDINGS NOT LOOKING VERY SUITABLE FOR MORE WIDESPREAD STORM COVERAGE...WILL KEEP PRECIP. CHANCES FAIRLY LOW DESPITE ELEVATED CAPE OF 1000-2000J/KG. FRIDAY THROUGH TUESDAY WILL CONTINUE TO BE ACTIVE AS THE CLOSED LOW OVER THE NORTHERN CONUS SLOWLY PLODS EAST WITH NUMEROUS SMALLER TROUGHS SOUTH OF IT MOVING OVER THE TRI-STATE AREA. THE BEST CHANCE FOR RAINFALL WILL BE SUNDAY NIGHT INTO MONDAY WHEN A DEEPER UPPER LEVEL TROUGH MOVES OVER THE AREA. GEFS MEMBERS HAVE HIGH CHANCES FOR RAINFALL FOR THAT NIGHT WHICH ADDS CONFIDENCE THAT THE AREA WILL RECEIVE RAINFALL. FAIRLY GOOD CHANCES FOR RAINFALL CONTINUE THROUGH MONDAY NIGHT AS SHORT WAVE TROUGHS CONTINUE TO MOVE OVER THE AREA. SINCE THESE SMALLER SCALE TROUGHS ARE TIED TO THE EASTWARD PROGRESS OF THE CLOSED LOW OVER THE NORTHERN CONUS...WOULD NOT BE SURPRISED IF MODELS PUSH THE HIGHER RAINFALL CHANCES AHEAD A DAY OR TWO BY THE TIME NEXT WEEK ARRIVES SINCE MODELS TEND TO MOVE CLOSED LOWS TOO FAST. TEMPERATURES THROUGH THE PERIOD WILL BE AROUND 10 DEGREES ABOVE NORMAL FRIDAY THEN COOL TO NEAR NORMAL SUNDAY THROUGH TUESDAY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1055 PM MDT TUE JUN 17 2014 VFR AT BOTH TERMINALS THROUGH THE TAF PERIOD. SURFACE LOW OVER COLORADO WILL MOVE TO NEBRASKA OVERNIGHT GRADUALLY SHIFTING WINDS TO SOUTHWEST. A WEAK COLD FRONT WILL MOVE THROUGH TERMINALS WEDNESDAY MORNING TEMPORARILY CHANGING WIND DIRECTION TO NORTHWEST UNTIL LATE AFTERNOON. THUNDERSTORMS ARE EXPECTED TO DEVELOP OVER COLORADO AND MOVE INTO VCNTY KGLD/KMCK BY EARLY EVENING. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...DLF SHORT TERM...DR LONG TERM...JTL AVIATION...DLF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
356 AM EDT WED JUN 18 2014 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 345 PM EDT TUE JUN 17 2014 WATER VAPOR IMAGERY AND RUC ANALYSIS INDICATE THAT THE SHORTWAVE RESPONSIBLE FOR LAST NIGHT/S AND THIS MORNING/S CONVECTION HAS PASSED EAST. BEHIND THE SHORTWAVE...RISING 5H RIDGE HGTS AND ASSOC INCREASED SUBSIDENCE AND Q-VECT DIVERGENCE FROM THE WEST LED TO CLEARING SKIES OVER THE WEST HALF OF THE CWA THIS MORNING AND OVER MUCH OF THE EAST HALF THIS AFTERNOON. MIXING 850 MB TEMPS OF 16-17C TO THE SFC YIELDED INLAND HIGH TEMPS IN THE LOWER TO MID 80S OVER THE INTERIOR WEST HALF OF UPPER MI THIS AFTERNOON. LAKE BREEZES HAVE KEPT TEMPS COOLER NEAR THE SHORELINES...GENERALLY IN THE 60S. MODIFIED RUC SNDGS OVER SCNTRL UPPER MI FOR 86/59 YIELD AROUND 800 J/KG. GIVEN THE INSTABILITY PERHAPS SOME CONVECTION COULD BE INITIATED ALONG DEVELOPING LAKE BREEZE BOUNDARIES OVER SCNTRL WI SO WILL CONTINUE TO CARRY SLIGHT CHC POPS INTO THE EVENING HRS. ANOTHER SHORTWAVE OVER ERN NE IS EXPECTED TO MOVE THROUGH SRN/CNTRL WI TONIGHT ALONG AND NORTH OF WARM FRONT. THIS SHORTWAVE WORKING ON AN ENVIRONMENT OF 1500-2500 J/KG WILL TRIGGER ANOTHER AROUND OF CONVECTION ACROSS WI INTO LOWER MI TONIGHT. MODELS INDICATE THAT THE NRN FRINGE OF THIS CONVECTION MAY BRUSH SCNTRL UPR MI MAINLY SRN MNM COUNTY WITH SOME SHRA/TSRA WHERE THERE REMAINS A FEW HUNDRED J/KG OF INSTABILITY. WILL CONTINUE TO CARRY SLIGHT CHC POPS TONIGHT FOR THIS POSSIBILITY BUT BEST CONVECTION SHOULD STAY WELL SOUTH CLOSER TO WARM FRONT AND BETTER INSTABILITY. INCREASINGLY CONFLUENT FLOW ALOFT AHEAD OF THE NRN PLAINS RIDGE INTO THE UPPER GREAT LAKES LATE TONIGHT INTO WEDNESDAY WILL CONTINUE TO ALLOW SFC RDGG FM HUDSON BAY HIGH TO WORK INTO THE UPPER GREAT LAKES. THIS SHOULD ENSURE MOSTLY DRY CONDITIONS ACROSS THE AREA ON WEDNESDAY. EXPECT SLIGHTLY COOLER HIGHS FROM UPPER 70S TO AROUND 80 INLAND WITH COOLER 60S TO LOWER 70S READINGS NEAR THE GREAT LAKES SHORELINES. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 329 PM EDT TUE JUN 17 2014 TWO UPPER TROUGHS WILL BE SURROUNDING THE UPPER GREAT LAKES REGION (ONE OVER THE NORTHERN ROCKIES AND THE OTHER FAR NORTHERN QUEBEC) TO START THE PERIOD...WITH ASSOCIATED SURFACE LOWS TO THE SOUTHEAST OF THE UPPER TROUGHS. OVER THE UPPER GREAT LAKES REGION...AN UPPER RIDGE AXIS WILL BE CENTERED OVER THE AREA...STRETCHING FROM THE OHIO RIVER VALLEY TO JUST WEST OF HUDSON BAY. A HUDSON BAY HIGH WILL BE ASSOCIATED WITH THIS RIDGE AND STRETCHING A SURFACE RIDGE SOUTH OVER EASTERN LAKE SUPERIOR AND LAKE HURON. THIS UPPER AND SURFACE RIDGE WILL GRADUALLY SHIFT EAST WEDNESDAY NIGHT THROUGH THURSDAY NIGHT...ALLOWING THE SHOWERS AND THUNDERSTORMS TO THE WEST OF THE AREA TO SHIFT FROM WEST TO EAST ACROSS THE CWA DURING THAT TIME. WILL KEEP THE SLIGHT CHANCE POPS THAT ARE RIGHT ALONG THE WISCONSIN BORDER WEDNESDAY NIGHT INTO THURSDAY MORNING...JUST IN CASE CONVECTION THAT FIRES CLOSER TO THE BETTER WARM AIR ADVECTION IN MINNESOTA BRUSHES THAT AREA AS IT MOVES SOUTHEAST. OTHERWISE...THE REST OF THE AREA WILL BE DRY WEDNESDAY NIGHT. WITH THE HUDSON BAY HIGH IN PLACE OVER THE EASTERN HALF OF THE CWA ON THURSDAY...EXPECT THE DRY EASTERLY FLOW TO TRY AND HOLD OFF ANY CONVECTION DEVELOPMENT OVER THE AREA FOR THURSDAY. THE BEST OPPORTUNITY WILL COME OVER THE FAR WEST TOWARDS THE LATER PART OF THE AFTERNOON...AS THE NEXT ROUND OF CONVECTION DEVELOPS IN MINNESOTA ON THURSDAY. WITH PROPAGATION VECTORS POINTING TO THE EAST-SOUTHEAST FROM CENTRAL/NORTHERN MINNESOTA...WOULD EXPECT ANY CONVECTION IN THAT AREA TO MOVE OVER WESTERN UPPER MICHIGAN THURSDAY EVENING. THOSE SHOWERS AND THUNDERSTORMS WOULD CONTINUE TO THE EAST THROUGH THE NIGHT...AIDED BY THE BROAD WARM AIR ADVECTION MOVING EASTWARD IN RESPONSE TO THE UPPER TROUGH LIFTING INTO THE NORTHERN PLAINS AND NORTHWEST MINNESOTA. THIS WILL SUPPORT SCATTERED SHOWERS AND SOME WEAK THUNDERSTORMS (MARGINAL INSTABILITY DUE TO WEAKENING MID LEVEL LAPSE RATES) OVER THE AREA ON FRIDAY (ESPECIALLY WEST/CENTRAL IN THE MORNING). WITH THE BROAD/WEAKENING WAA CONTINUING EAST LATER FRIDAY AFTERNOON INTO FRIDAY NIGHT...EXPECT A PERIOD OF NO PRECIP OVER PORTIONS OF THE AREA AS THE UPPER TROUGH TO THE WEST MERGES WITH THE EASTERN UPPER TROUGH. THIS MERGING OF THE UPPER TROUGHS WILL PULL THE LEFT OVER UPPER WAVE AND WEAK SURFACE LOW SOUTHEAST ACROSS THE UPPER GREAT LAKES REGION THIS WEEKEND. THERE CONTINUES TO BE SOME DIFFERENCES ON THE MERGING OF THE TROUGHS AND HOW QUICKLY IT SWEEPS THROUGH... BUT IT DOES APPEAR THAT THERE WILL BE A PERIOD OF STEADIER RAIN MOVING THROUGH THE AREA AT SOME POINT THIS WEEKEND. THE UPPER TROUGH WILL SLIDE SOUTHEAST ON SUNDAY NIGHT AND ALLOW AN UPPER RIDGE FROM THE NORTHERN PLAINS AND CENTRAL CANADA TO MOVE SOUTHEAST INTO THE AREA AND PRODUCE CLEARING SKIES AND SEASONABLE TEMPERATURES. ALSO NEED TO POINT OUT THAT THE DRY EASTERLY FLOW ON THURSDAY AND A MOSTLY SUNNY SKY WILL ALLOW FOR DEEP MIXING AND RH VALUES FALLING TOWARDS 20-25 PERCENT OVER THE EASTERN THIRD OF THE CWA. LIGHT RAINS IN THAT AREA DURING THE LAST 2 DAYS HAS IMPROVED FFMC VALUES...BUT DRY CONDITIONS TODAY AND WEDNESDAY SHOULD ALLOW THE FINE FUELS TO DRY BACK OUT BY THURSDAY. FORTUNATELY...WIND GUSTS SHOULD ONLY BE IN THE 10-20MPH RANGE ON THURSDAY AND LIMIT THE WILDFIRE CONCERNS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1203 AM EDT WED JUN 18 2014 VFR CONDITIONS SHOULD PREVAIL AT KIWD/KCMX/KSAW THROUGH THIS FCST PERIOD AS LOW-LEVELS REMAIN RELATIVELY DRY UNDER DOMINANT HIGH PRESSURE. SOME SHRA/TSRA MAY DEVELOP OVER SOUTHERN AND POSSIBLY INTO CENTRAL UPPER MICHIGAN LATE TONIGHT. HOWEVER...SINCE THE GREATER INSTABILITY TO SUPPORT PCPN REMAINS TO THE SOUTH OVER WI...CONFIDENCE WAS TOO LOW TO INCLUDE MENTION IN THE TAF. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 355 AM EDT WED JUN 18 2014 FOG IS STILL BEING REPORTED EARLY THIS MORNING...MAINLY OVER N LAKE MI AND FAR E LAKE SUPERIOR. EXPECT THIS FOG TO CONTINUE TO SLOWLY DIMINISH THIS MORNING INTO THE EARLY AFTERNOON HOURS. DRIER HIGH PRESSURE OVER S HUDSON BAY WILL REMAIN NEARLY STATIONARY THROUGH THE UPCOMING WEEKEND. A RIDGE EXTENDING FROM THE HIGH TOWARD LAKE SUPERIOR WILL STRENGTHEN AS IT BUILDS TOWARD THE LOWER GREAT LAKES THROUGH THURSDAY NIGHT /BRINGING WITH IT DRIER AIR/. LOOK FOR FUNNELING NE WINDS OVER THE W THIRD OF LAKE SUPERIOR...WITH GUSTS ON THE ORDER OF 20-25KTS. THE RIDGE WILL THEN WEAKEN AND DRIFT E FRIDAY AND SATURDAY AS LOW PRESSURE OVER SE SASKATCHEWAN MOVES TOWARD N MINNESOTA. THE LOW WILL DRIFT SE INTO THE UPPER GREAT LAKES SUNDAY. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... DENSE FOG ADVISORY UNTIL NOON EDT TODAY FOR LSZ248>251-265>267. LAKE MICHIGAN... NONE. && $$ SHORT TERM...VOSS LONG TERM...SRF AVIATION...JLB MARINE...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1204 AM EDT WED JUN 18 2014 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 345 PM EDT TUE JUN 17 2014 WATER VAPOR IMAGERY AND RUC ANALYSIS INDICATE THAT THE SHORTWAVE RESPONSIBLE FOR LAST NIGHT/S AND THIS MORNING/S CONVECTION HAS PASSED EAST. BEHIND THE SHORTWAVE...RISING 5H RIDGE HGTS AND ASSOC INCREASED SUBSIDENCE AND Q-VECT DIVERGENCE FROM THE WEST LED TO CLEARING SKIES OVER THE WEST HALF OF THE CWA THIS MORNING AND OVER MUCH OF THE EAST HALF THIS AFTERNOON. MIXING 850 MB TEMPS OF 16-17C TO THE SFC YIELDED INLAND HIGH TEMPS IN THE LOWER TO MID 80S OVER THE INTERIOR WEST HALF OF UPPER MI THIS AFTERNOON. LAKE BREEZES HAVE KEPT TEMPS COOLER NEAR THE SHORELINES...GENERALLY IN THE 60S. MODIFIED RUC SNDGS OVER SCNTRL UPPER MI FOR 86/59 YIELD AROUND 800 J/KG. GIVEN THE INSTABILITY PERHAPS SOME CONVECTION COULD BE INITIATED ALONG DEVELOPING LAKE BREEZE BOUNDARIES OVER SCNTRL WI SO WILL CONTINUE TO CARRY SLIGHT CHC POPS INTO THE EVENING HRS. ANOTHER SHORTWAVE OVER ERN NE IS EXPECTED TO MOVE THROUGH SRN/CNTRL WI TONIGHT ALONG AND NORTH OF WARM FRONT. THIS SHORTWAVE WORKING ON AN ENVIRONMENT OF 1500-2500 J/KG WILL TRIGGER ANOTHER AROUND OF CONVECTION ACROSS WI INTO LOWER MI TONIGHT. MODELS INDICATE THAT THE NRN FRINGE OF THIS CONVECTION MAY BRUSH SCNTRL UPR MI MAINLY SRN MNM COUNTY WITH SOME SHRA/TSRA WHERE THERE REMAINS A FEW HUNDRED J/KG OF INSTABILITY. WILL CONTINUE TO CARRY SLIGHT CHC POPS TONIGHT FOR THIS POSSIBILITY BUT BEST CONVECTION SHOULD STAY WELL SOUTH CLOSER TO WARM FRONT AND BETTER INSTABILITY. INCREASINGLY CONFLUENT FLOW ALOFT AHEAD OF THE NRN PLAINS RIDGE INTO THE UPPER GREAT LAKES LATE TONIGHT INTO WEDNESDAY WILL CONTINUE TO ALLOW SFC RDGG FM HUDSON BAY HIGH TO WORK INTO THE UPPER GREAT LAKES. THIS SHOULD ENSURE MOSTLY DRY CONDITIONS ACROSS THE AREA ON WEDNESDAY. EXPECT SLIGHTLY COOLER HIGHS FROM UPPER 70S TO AROUND 80 INLAND WITH COOLER 60S TO LOWER 70S READINGS NEAR THE GREAT LAKES SHORELINES. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 329 PM EDT TUE JUN 17 2014 TWO UPPER TROUGHS WILL BE SURROUNDING THE UPPER GREAT LAKES REGION (ONE OVER THE NORTHERN ROCKIES AND THE OTHER FAR NORTHERN QUEBEC) TO START THE PERIOD...WITH ASSOCIATED SURFACE LOWS TO THE SOUTHEAST OF THE UPPER TROUGHS. OVER THE UPPER GREAT LAKES REGION...AN UPPER RIDGE AXIS WILL BE CENTERED OVER THE AREA...STRETCHING FROM THE OHIO RIVER VALLEY TO JUST WEST OF HUDSON BAY. A HUDSON BAY HIGH WILL BE ASSOCIATED WITH THIS RIDGE AND STRETCHING A SURFACE RIDGE SOUTH OVER EASTERN LAKE SUPERIOR AND LAKE HURON. THIS UPPER AND SURFACE RIDGE WILL GRADUALLY SHIFT EAST WEDNESDAY NIGHT THROUGH THURSDAY NIGHT...ALLOWING THE SHOWERS AND THUNDERSTORMS TO THE WEST OF THE AREA TO SHIFT FROM WEST TO EAST ACROSS THE CWA DURING THAT TIME. WILL KEEP THE SLIGHT CHANCE POPS THAT ARE RIGHT ALONG THE WISCONSIN BORDER WEDNESDAY NIGHT INTO THURSDAY MORNING...JUST IN CASE CONVECTION THAT FIRES CLOSER TO THE BETTER WARM AIR ADVECTION IN MINNESOTA BRUSHES THAT AREA AS IT MOVES SOUTHEAST. OTHERWISE...THE REST OF THE AREA WILL BE DRY WEDNESDAY NIGHT. WITH THE HUDSON BAY HIGH IN PLACE OVER THE EASTERN HALF OF THE CWA ON THURSDAY...EXPECT THE DRY EASTERLY FLOW TO TRY AND HOLD OFF ANY CONVECTION DEVELOPMENT OVER THE AREA FOR THURSDAY. THE BEST OPPORTUNITY WILL COME OVER THE FAR WEST TOWARDS THE LATER PART OF THE AFTERNOON...AS THE NEXT ROUND OF CONVECTION DEVELOPS IN MINNESOTA ON THURSDAY. WITH PROPAGATION VECTORS POINTING TO THE EAST-SOUTHEAST FROM CENTRAL/NORTHERN MINNESOTA...WOULD EXPECT ANY CONVECTION IN THAT AREA TO MOVE OVER WESTERN UPPER MICHIGAN THURSDAY EVENING. THOSE SHOWERS AND THUNDERSTORMS WOULD CONTINUE TO THE EAST THROUGH THE NIGHT...AIDED BY THE BROAD WARM AIR ADVECTION MOVING EASTWARD IN RESPONSE TO THE UPPER TROUGH LIFTING INTO THE NORTHERN PLAINS AND NORTHWEST MINNESOTA. THIS WILL SUPPORT SCATTERED SHOWERS AND SOME WEAK THUNDERSTORMS (MARGINAL INSTABILITY DUE TO WEAKENING MID LEVEL LAPSE RATES) OVER THE AREA ON FRIDAY (ESPECIALLY WEST/CENTRAL IN THE MORNING). WITH THE BROAD/WEAKENING WAA CONTINUING EAST LATER FRIDAY AFTERNOON INTO FRIDAY NIGHT...EXPECT A PERIOD OF NO PRECIP OVER PORTIONS OF THE AREA AS THE UPPER TROUGH TO THE WEST MERGES WITH THE EASTERN UPPER TROUGH. THIS MERGING OF THE UPPER TROUGHS WILL PULL THE LEFT OVER UPPER WAVE AND WEAK SURFACE LOW SOUTHEAST ACROSS THE UPPER GREAT LAKES REGION THIS WEEKEND. THERE CONTINUES TO BE SOME DIFFERENCES ON THE MERGING OF THE TROUGHS AND HOW QUICKLY IT SWEEPS THROUGH... BUT IT DOES APPEAR THAT THERE WILL BE A PERIOD OF STEADIER RAIN MOVING THROUGH THE AREA AT SOME POINT THIS WEEKEND. THE UPPER TROUGH WILL SLIDE SOUTHEAST ON SUNDAY NIGHT AND ALLOW AN UPPER RIDGE FROM THE NORTHERN PLAINS AND CENTRAL CANADA TO MOVE SOUTHEAST INTO THE AREA AND PRODUCE CLEARING SKIES AND SEASONABLE TEMPERATURES. ALSO NEED TO POINT OUT THAT THE DRY EASTERLY FLOW ON THURSDAY AND A MOSTLY SUNNY SKY WILL ALLOW FOR DEEP MIXING AND RH VALUES FALLING TOWARDS 20-25 PERCENT OVER THE EASTERN THIRD OF THE CWA. LIGHT RAINS IN THAT AREA DURING THE LAST 2 DAYS HAS IMPROVED FFMC VALUES...BUT DRY CONDITIONS TODAY AND WEDNESDAY SHOULD ALLOW THE FINE FUELS TO DRY BACK OUT BY THURSDAY. FORTUNATELY...WIND GUSTS SHOULD ONLY BE IN THE 10-20MPH RANGE ON THURSDAY AND LIMIT THE WILDFIRE CONCERNS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1203 AM EDT WED JUN 18 2014 VFR CONDITIONS SHOULD PREVAIL AT KIWD/KCMX/KSAW THROUGH THIS FCST PERIOD AS LOW-LEVELS REMAIN RELATIVELY DRY UNDER DOMINANT HIGH PRESSURE. SOME SHRA/TSRA MAY DEVELOP OVER SOUTHERN AND POSSIBLY INTO CENTRAL UPPER MICHIGAN LATE TONIGHT. HOWEVER...SINCE THE GREATER INSTABILITY TO SUPPORT PCPN REMAINS TO THE SOUTH OVER WI...CONFIDENCE WAS TOO LOW TO INCLUDE MENTION IN THE TAF. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 345 PM EDT TUE JUN 17 2014 LINGERING HIGH DEWPOINTS ACROSS THE AREA WILL WARRANT MENTION OF PATCHY FOG OVER THE WEST INTO WEDNESDAY AND AREAS OF FOG OVER THE EAST HALF OF THE LAKE. SHIP REPORTS AND WEB CAMS CONFIRM THAT MUCH OF THE FOG OVER THE EAST HALF IS DENSE SO HAVE ISSUED A DENSE FOG ADVISORY THROUGH WED MORNING. A TROUGH OF LOW PRESSURE OVER LAKE SUPERIOR TODAY WILL BE SLOWLY REPLACED BY A RIDGE THIS EVENING...EXTENDING FROM HIGH PRESSURE ACROSS SOUTHERN HUDSON BAY AND NORTHERN ONTARIO. LIGHT WINDS WILL BECOME NE...AND FUNNEL OVER THE W HALF OF LAKE SUPERIOR...WITH GUSTS OF 20-25KTS LATE TONIGHT INTO THURSDAY. THE RIDGE WILL SLOWLY SHIFT EAST FRIDAY...AS LOW PRESSURE ACROSS SOUTHERN MANITOBA AND NORTH DAKOTA APPROACHES NORTHERN MINNESOTA...BRINGING THE RETURN OF THUNDERSTORMS FRIDAY INTO SUNDAY. EXPECT THE LOW TO SHIFT ACROSS THE UPPER GREAT LAKES ON SATURDAY. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... DENSE FOG ADVISORY UNTIL NOON EDT TODAY FOR LSZ248>251-265>267. LAKE MICHIGAN... NONE. && $$ SHORT TERM...VOSS LONG TERM...SRF AVIATION...JLB MARINE...VOSS
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
408 AM CDT WED JUN 18 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 311 AM CDT WED JUN 18 2014 YET ANOTHER STORMY SHORT TERM PERIOD IS ON TAP WITH THIS PERIOD LOOKING TO CONTINUE THE TREAT FOR SEVERE WEATHER AND FLASH FLOODING. AT 4 AM...THE WARM FRONT WAS SPLAYED OUT FROM NEAR YANKTON ENE TO JUST NORTH OF I-90 IN SRN MN. YET ANOTHER ENHANCEMENT OF THE LLJ HAS PROVIDED ENOUGH ISENTROPIC LIFT TO OVERCOME THE CAP THE MOVED IN YESTERDAY TO ALLOW THUNDERSTORMS TO BLOSSOM ACROSS THE MN/IA BORDER REGION. STORMS IN THE MPX CWA HAVE REMAINED MAINLY ELEVATED...THOUGH STORMS ACROSS NRN IA HAVE BEEN ABLE TO BASICALLY MAINTAIN THEIR SFC CONNECTION...HENCE THE TORNADO THAT HAPPENED IN THE SPENCER AREA AFTER 1 AM. THOUGH NOT ROOTED AT THE SFC...PWATS NEAR 1.75" COMBINED WITH FREEZING LEVELS OVER 14K FEET HAS RESULTED IN RAINFALL RATES IN EXCESS OF 2 IN/HR OVERNIGHT. EXPECT THIS ACTIVITY TO SLOWLY DRIFT EAST WHILE WEAKENING OVER THE NEXT FEW HOURS AS THE LLJ BEGINS TO VEER OVER TO THE EAST AND WEAKEN THE REST OF THE MORNING. BASED ON THE HRRR AND RAP H85 MOISTURE TRANSPORT FORECAST...EXPECT THIS ACTIVITY TO HANG AROUND THROUGH ABOUT 15Z BEFORE WE GET INTO ANOTHER PRECIP BREAK THAT LOOKS TO LAST MOST OF THE AFTERNOON. MAIN QUESTION FOR THIS AFTERNOON IS WHERE WILL THE WARM FRONT SETUP. ACTIVITY RIGHT NOW WILL AGAIN FORCE THE WARM FRONT SOUTH INTO IA...LIKELY DOWN TO NEAR THE I-80 CORRIDOR. IN ADDITION TO THAT...IN THE WAKE OF THIS MORNINGS CONVECTION...THE RAP SHOWS THE 12C ISOTHERM AT H7 WORKING BACK UP INTO CENTRAL MN...WHICH WILL PUT A LID ON THINGS THROUGH THE AFTERNOON...MUCH LIKE WE JUST SAW YESTERDAY. LOOKING AT LLJ EVOLUTION...DURING THE AFTERNOON...IT WILL BACK TOWARD THE NORTHWEST AND STRENGTHEN ACROSS THE ERN DAKOTAS...WHICH WILL SHIFT THE FOCUS FOR THUNDERSTORMS FROM THE MS VALLEY BACK INTO THE DAKOTAS BY THE AFTERNOON. AS A RESULT...DELAYED ANY RAMP UP IN POPS TO LIKELIES UNTIL AFTER 00Z...TRYING ORIENT THINGS TOWARD THE NSSL/NMM/ARW WRFS...WHICH SHOW STORMS BLOSSOMING ONCE AGAIN AFTER 3Z. THIS IS IN CONJUNCTION WITH THE ARRIVAL OF THE WARM FRONT...WHICH LOOKS TO SURGE NORTH OUT OF IA THIS EVENING IN RESPONSE TO THE SFC LOW CURRENTLY OVER NE COLORADO WORKING OVER TO NEAR ABERDEEN TONIGHT. WHAT DOES THIS MEAN FOR THE SEVERE THREAT? WELL...ONE THING THAT IS FOR SURE IS INSTABILITY WILL NOT BE ISSUE...AS WE SHOULD SEE MLCAPES IN THE WARM SECTOR AGAIN PUSH 5000 J/KG. FOR A TORNADO THREAT...WE WOULD HAVE TO BANK ON ACTIVITY FORMING ALONG THE WARM FRONT AS IT MOVES NORTH. INSTEAD...FEEL OUR MAIN SEVERE THREAT WILL EXIST MAINLY OVERNIGHT WITH ANY SORT OF SYSTEM THAT COMES OUT OF THE DAKOTAS DURING THE AFTERNOON ALONG WITH STORMS THAT DEVELOP NORTH OF THE WARM FRONT AS IT WORKS INTO MN OVERNIGHT. DEEP LAYER SHEAR LOOKS TO BE MARGINALLY WEAKER WEDNESDAY GIVEN THE PRESENCE OF AN UPPER RIDGE...BUT THE STRONG INSTABILITY AND STEEP MID-LEVEL LAPSE RATES WILL BE MORE THAN ENOUGH TO KEEP A WIND/HAIL TREAT GOING THROUGH MUCH OF THE NIGHT. THERE WILL ALSO BE A CONTINUED FLASH FLOOD THREAT WITH THIS ACTIVITY AS WELL. DECIDED ON NOT ISSUING A FLASH FLOOD WATCH AT THIS TIME AS THERE IS ENOUGH UNCERTAINTY AS TO WHERE THIS ROUND OF HEAVY RAIN WILL SET UP THAT IT WAS TO DIFFICULT TO NARROW DOWN A CORRIDOR FOR WHERE ONE WOULD BE NEEDED. WITH THE 00Z CAMS...THERE IS A FAVORED CORRIDOR FOR HEAVY PRECIP FROM SE MN BACK NW TOWARD THE MN/ND/SD BORDER. HOWEVER...THIS WILL LIKELY CHANGE ONCE IT IS BETTER KNOWN WHERE THAT WARM FRONT SETS UP THIS EVENING. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 311 AM CDT WED JUN 18 2014 CONVECTION SHOULD BE ONGOING THURSDAY MORNING WITH A MODEST LLJ AND 925-850MB MOISTURE TRANSPORT ACROSS THE ENTIRE FORECAST AREA. A NW-SE ORIENTATED WARM FRONT SHOULD EXTEND ROUGHLY FROM FARGO...TO DAVENPORT...TO CHICAGO BY 12Z THURSDAY MORNING. THIS WILL BE THE FOCUS FOR SCATTERED TO NUMEROUS THUNDERSTORMS. PWATS SHOULD STILL BE RUNNING HIGH WITH 1.50-1.90" ACROSS THE FORECAST AREA AND THE MEAN STEERING WINDS INDICATE A SLOWER STORM MOTION...THEREFORE FLASH FLOODING WILL CONTINUE TO BE A THREAT. THE OVERALL RISK FOR SEVERE APPEARS FAIRLY LOW...BUT THERE IS ENOUGH DEEP LAYER SHEAR AND MODEST STABILITY TO PROVIDE A MINOR WIND AND HAIL THREAT. THE COLD FRONT AND GRADUALLY FILLING SURFACE LOW WILL EXTEND BACK TOWARD THE WEST IN THE CENTRAL AND NORTHERN PLAINS. THE FRONTAL BOUNDARIES WILL LOSE SOME OF THEIR DEFINITION AS THEY MOVE EAST...BUT A SLIGHTLY DRIER AIR MASS ENTERS WESTERN MN BY THURSDAY AFTERNOON AND EVENING. FRIDAY COULD ACTUALLY BE A DRY DAY ACROSS MOST OF MN WITH THE BOUNDARIES HAVING SHIFTED EAST INTO CENTRAL AND EASTERN WI AND THE LOW LEVEL FLOW BECOMING MUCH WEAKER. A WARM AND MAINLY ZONAL PATTERN SETS UP FOR THE WEEKEND...BUT THERE IS STILL A WEAK SURFACE TROUGH HANGING AROUND THE FORECAST AREA...SO WE CAN SIMPLY NOT GO WITH A DRY FORECAST. THE GOOD NEWS LOCALLY /BAD NEWS FOR SOGGY IA/ IS THAT THE NOCTURNAL LLJ FOCUSES SOUTH OF THE AREA FRI/SAT/SUN. THIS SUGGESTS A LOWER THREAT FOR HEAVY RAIN AND FLASH FLOODING. TEMPERATURES LOOK TO REMAIN NEAR OR ABOVE NORMAL THROUGH EARLY NEXT WEEK. THE 18.00Z ECMWF BRINGS A PSEUDO BACK DOOR COLD FRONT ACROSS THE AREA ON TUE-WED...BUT THE PAST COUPLE RUNS OF THE GFS DOES NOT SHOW IT AT THIS TIME. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1241 AM CDT WED JUN 18 2014 SCATTERED TO NUMEROUS THUNDERSTORMS WILL AFFECT SOUTHERN MN AND PORTIONS OF WEST CENTRAL WI THROUGH THE EARLY MORNING. MOST OF THIS ACTIVITY WILL REMAIN SOUTH OF THE TAF SITES...BUT KEAU AND KRWF WILL CONTINUE TO SEE THUNDER. AT THE OTHER TAF SITES...THE THUNDER THREAT IS TOO UNCERTAIN THIS MORNING TO INCLUDE AT THIS POINT. THERE IS THE CHANCE...HOWEVER...OF MVFR STRATUS THIS MORNING. KMSP... WE THINK THERE WILL BE WIDESPREAD THUNDERSTORMS SOUTH OF THE AIRPORT FOR MOST OF THE EARLY MORNING HOURS...PERHAPS LINGERING PAST SUNRISE. AT THE AIRPORT ITSELF...THE UNCERTAINTY IN STORM COVERAGE THIS FAR NORTH KEEPS US FROM INCLUDING IN THE TAF EARLY THIS MORNING. WE WILL MONITOR CLOSE AND UPDATE BASED ON CURRENT RADAR TRENDS AS WE APPROACH THE MORNING COMMUTE. /OUTLOOK FOR KMSP/ THU...MVFR/IFR WITH SHRA/TSRA LIKELY. WINDS SE 10-15 KTS. FRI...VFR. MVFR SHRA/TSRA POSSIBLE. WINDS SW 10 KTS. SAT...VFR. MVFR SHRA/TSRA POSSIBLE. WINDS W 10 KTS. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...FLASH FLOOD WATCH UNTIL 7 AM CDT THIS MORNING FOR MNZ082>085- 091>093. WI...NONE. && $$ SHORT TERM...MPG LONG TERM...CLF AVIATION...CLF HYDROLOGY...CLF
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1102 PM CDT Tue Jun 17 2014 .UPDATE: Issued at 906 PM CDT Tue Jun 17 2014 Latest HRRR model run keeps any convection north of our forecast area through 12Z Wednesday, although the latest NAM model still has convection across northeast MO and west central IL late tonight. Will keep slight chance pops at least across the extreme northern portion of the forecast area late tonight. Unseasonably warm low temperatures are expected again tonight, about 10 degrees above normal with continued southerly winds and high surface dew points. GKS && .SHORT TERM: (Through Late Tonight) Issued at 330 PM CDT Tue Jun 17 2014 The primary concern tonight is whether we may see any showers or thunderstorms across far northern sections of the CWA. The main focus remains the quasi-stationary boundary stretching from eastern Nebraska across Iowa into the lower Great Lakes region. Any of this activity should have an eastward component of motion, however the possibility of scenario similar to late last night/early this morning is within the realm of possibilities. That is, a remnant outflow boundary could push south in to the area and lift associated with the southwesterly LLJ on its flank could result in some showers and thunderstorms. Also mid level temperatures are forecast to cool a tad overnight and steep lapse rates will be present so there is even some potential for high based activity in the same general location. I have added a low pop across northeast MO and west central IL to account for the possibility but with low confidence. Elsewhere a mild night is on tap with lows in the 70s. Glass .LONG TERM: (Wednesday through Next Tuesday) Issued at 330 PM CDT Tue Jun 17 2014 Another seasonably hot and humid day is on tap for the area on Wednesday. Tempeatures haven`t gotten as warm today as initially anticipated and see no reason to go much warmer than some variation of upper 80s-lower 90s since temperatures aloft are actually forecast to cool slightly. The models continue to generate either some spotty or light QPF on Wednesday afternoon and this might be a signal of the anticipated increasing chance of isolated diurnally driven thunderstorms I have alluded to the last several days. Mid level cooling on the order of 2-3 degrees will result in little CIN during peak afternoon heating, it is just a question of impetus. Also there is a signal that some remnant boundary may be flirting around across west central and south central IL. As a result I have some low pops going for a dual fold threat but there is a good degree of uncertainty. The threat of showers and thunderstorms gradually ramps up on Wednesday night and especially Thursday into Friday. On Wednesday night due to potential for MCS remnants progressing into the northern CWA. On Thursday we see a more focused zone of moisture/instability progress into the area ahead of the encroaching cold front and continued mid level cooling as the ridging aloft breaks down. And by Friday there are indications that this front makes some progress into the CWA as ridging aloft breaks down further and flow aloft becomes more westerly. This westerly flow also contains weak impulses contributing to large scale support. This front may be lingering either just to our north or across parts of the CWA into Saturday and Sunday with a wavy structure. Sunday into early next week, an upper low/trof in the vicinity of the central U.S./Canadian border will track sewd through the Great Lakes/Ohio Valley region sending another front into the CWA that will slowly move southward keeping an ongoing threat of showers and thunderstorms. Glass && .AVIATION: (For the 06z TAFs through 06z Wednesday Night) Issued at 1053 PM CDT Tue Jun 17 2014 Main concern for aviation over the next 24 hours continues to be on the possibility of convection affecting the terminals. Believe TAF sites will stay dry through the valid period...though cannot rule out some isolated storms tonight over northeast Missouri and west central Illinois near KUIN nor anywhere during the day tomorrow as atmosphere becomes very unstable with little to no cap. However...forcing necessary to initiate convection is lacking...so believe coverage in any storms would be too low to mention in TAFs for now...if anything develops at all. Winds have slackened quite a bit from earlier today but will pick back up and become gusty again by mid morning before pressure gradient relaxes and winds lighten up again Wednesday afternoon/evening. Specifics for KSTL: Main concern for aviation over the next 30 hours continues to be on the possibility of convection affecting the terminal. Stayed with a dry TAF through the valid period...though cannot rule out some isolated storms during the day on Wednesday as atmosphere becomes very unstable with little to no cap. However...forcing necessary to initiate convection is lacking...so believe coverage in any storms would be too low to mention in TAF for now...if anything develops at all. Winds have slackened quite a bit from earlier today but will pick back up and become gusty again by mid morning before pressure gradient relaxes and winds lighten up again Wednesday afternoon/evening. Gosselin && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
416 AM CDT WED JUN 18 2014 .SHORT TERM...(TODAY THROUGH FRIDAY) ISSUED AT 400 AM CDT WED JUN 18 2014 FORECAST CONCERNS THROUGH THE SHORT TERM WILL CONTINUE TO BE TRYING TO PIN DOWN THUNDERSTORM/SEVERE WEATHER CHANCES ALONG WITH THE HEAT ON WEDNESDAY. AN ISOLATED TORNADIC THUNDERSTORM INDEED DEVELOPED NEAR THE SOUTH DAKOTA BORDER THIS EVENING AND LASTED FOR SEVERAL HOURS OVER CEDAR COUNTY. THE 00Z OAX SOUNDING WAS IMPRESSIVE WITH CAPE OF NEARLY 6400 J/KG AND LITTLE CIN. ALSO OF NOTE WERE THE VERY STEEP LAPSE RATES AND H85 MOISTURE OF 17 DEG. C. A RARE 06Z SOUNDING WAS REQUESTED AND SHOWED AN UNSTABLE ATMOSPHERE WITH NEARLY 5000 J/KG OF CAPE AND 1.64 PWAT. EARLY THIS MORNING...THE MAIN CONVECTIVE COMPLEX IS OVER SOUTHERN MINNESOTA AND NORTHERN IOWA...CLOSER TO THE SURFACE AND H85 WARM FRONT. THE LOW LEVEL JET IS FORECAST TO REMAIN STRONG...40-50KTS OVER KANSAS AND MISSOURI THROUGH 15Z AND THERE IS AN APPROACHING H5 SPEED MAX. IT IS UNCERTAIN IF THIS LOW LEVEL JET CAN GET SOMETHING ELEVATED GOING OVER SOUTHEAST NEBRASKA AND SOUTHWEST IOWA. MOST OF THE OPERATIONAL MODELS ARE DRY THROUGH 21Z. THE EAX 4KM WRF HINTS AT SOMETHING IN THE MORNING ALONG WITH THE SREF. WILL LEAVE MOST OF THE FORECAST AREA DRY...HOWEVER WILL KEEP A SMALL POP IN FOR SOUTHWEST IOWA SHOULD SOMETHING ELEVATED MANAGE TO DEVELOP. THIS WILL NEED TO BE MONITORED THIS A.M. THIS AFTERNOON...THE HEAT BUILDS INTO THE FORECAST AREA WITH HIGHS AGAIN IN THE 90S. MEANWHILE...THE COLD FRONT IS FORECAST TO MOVE INTO CENTRAL NEBRASKA AND THE UPPER LEVEL SUPPORT MOVES INTO THE ROCKIES. THERE ARE A COUPLE OF LOCATIONS FOR CONVECTION...THE PRIMARY FOCUS APPEARS TO BE CLOSER TO THE HEIGHT FALLS...THE COLD FRONT AND THE DEEPENING SURFACE LOW. A SECOND AREA OF CONVECTION MAY DEVELOP IN IOWA AND BUILD BACK INTO THE FORECAST AREA. THE RAP SHOWS A CAP THIS MORNING WITH ELEVATED INSTABILITY AND DESTABILIZATION THIS AFTERNOON WITH THE EROSION OF THE CAP AFTER 20Z AND VERY STEEP LAPSE RATES WITH CAPE AROUND 3000 J/KG. THE NAM/GFS ARE MORE AGGRESSIVE WITH INSTABILITY WITH CAPE OF 4000-6000 J/KG. THE NAM HAS STRONGER DEEP LAYER SHEAR NEAR THE MISSOURI RIVER INTO WESTERN IOWA...WHILE THE GFS HOLDS THE STRONGER SHEAR TO THE WEST OF THE FORECAST AREA UNTIL AFTER MIDNIGHT. WITH HIGH INSTABILITY IN PLACE...SEVERE WEATHER WILL BE POSSIBLE WHERE STORMS DEVELOP. THE STORM PREDICTION CENTER HAS THE ENTIRE FORECAST AREA IN THE SLIGHT RISK AREA. WILL BEGIN TO INCREASE THUNDERSTORM CHANCES LATER THIS AFTERNOON AND CONTINUE TONIGHT AND THURSDAY AS THE UPPER LEVEL STORM SYSTEM MOVES INTO THE PLAINS AND DRIVES THE COLD FRONT THROUGH. WITH THE HIGH INSTABILITY AND FRONTAL BOUNDARIES THERE WILL BE A TORNADO THREAT. THE RAP HAS MORE OF A PRONOUNCED DRYLINE WORKING INTO CENTRAL AND NORTHEAST NEBRASKA. THE NAM HAS A DOUBLE WARMFRONT STRUCTURE WITH NORTHEAST NEBRASKA AND PARTS OF WEST IOWA ALONG WITH AREAS IN SD/MN WITH BACKED FLOW...WHILE THE GFS/EC IS FARTHER NORTH. PLACEMENT OF THESE FEATURES WILL BE KEY TO WHERE THE HIGHER TORNADO POTENTIAL IS. HAIL AND DAMAGING WINDS WILL BE POSSIBLE WITH THE CONVECTIVE COMPLEXES THAT DEVELOP TONIGHT AND THURSDAY. DEEP MOISTURE WITH PWATS OF 1.5 TO 2 INCHES RETURN AND LOCALLY HEAVY RAINFALL IS POSSIBLE...ESPECIALLY WHERE CONVERGENCE IS INCREASED IN THE VICINITY OF THE FRONTS. HIGH TEMPERATURES SHOULD TOP OUT IN THE 90S WITH HEAT INDEX VALUES AGAIN AROUND 100. THURSDAY/S HIGHS SHOULD BE IN THE 80S. THERE IS A BREAK IN THE RAIN CHANCES THURSDAY NIGHT...HOWEVER THE PUSH OF THE SHORTWAVE WEAKEN AND RETURN FLOW INCREASES WITHE THE CHANCE FOR RAIN. .LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY) ISSUED AT 400 AM CDT WED JUN 18 2014 THE EXTENDED REMAINS UNSETTLED WITH AT OR BELOW NORMAL HIGHS IN THE 80S. && .AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1126 PM CDT TUE JUN 17 2014 VFR CONDITIONS ARE INDICATED THROUGH THE TAF CYCLE. WINDS WILL REMAIN 10-15KT OVERNIGHT...THEN INCREASING AND BECOMING MORE SOUTHERLY TO SOUTHWESTERLY DIURNALLY. SHOULD SEE INCREASING MID- LEVEL CLOUDS IN THE LATE AFTERNOON THROUGH EVENING AS CONVECTION DEVELOPS IN THE AREA. FOR NOW...INCLUDED VCSH IN KOMA/KLNK AFTER 00Z. SHRA/TSRA COULD APPROACH OR PASS OVER TAF SITES IN THAT TIME FRAME...BUT WILL HOLD OFF MENTION TO GAIN MORE CONFIDENCE ON PLACEMENT AND TIMING. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ SHORT TERM...ZAPOTOCNY LONG TERM...ZAPOTOCNY AVIATION...MAYES
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1236 AM CDT WED JUN 18 2014 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 315 PM CDT TUE JUN 17 2014 MAP ANALYSIS INDICATES A CLOSED UPPER TROPOSPHERIC LOW OVER THE NORTHWESTERN CONUS...AND A RIDGE OVER THE EAST. ENHANCED UPPER TROPOSPHERIC FLOW EXTENDS FROM THE SOUTHWESTERN CONUS...NORTHEAST INTO THE CENTRAL AND NORTHERN PLAINS...AND THEN FARTHER NORTHEAST INTO THE GREAT LAKES REGION AND SOUTHEASTERN CANADA. UPPER TROPOSPHERIC FLOW OVER OUR AREA MAXES OUT AT AROUND 55KTS NEAR 37000FT AGL PER 12Z SOUNDING DATA FROM KLBF AND KOAX. WATER VAPOR IMAGERY INDICATES ENHANCED UPPER TROPOSPHERIC MOISTURE EXTENDS FROM THE SOUTHERN PLAINS INTO THE GREAT LAKES REGION...AS WELL AS OVER PORTIONS OF THE ROCKY MOUNTAIN RANGE. AT THE SURFACE A STATIONARY BOUNDARY IS NOTED EXTENDING FROM NORTH CENTRAL NEBRASKA INTO SOUTHWESTERN NEBRASKA AND THE CENTRAL HIGH PLAINS. IN ADDITION...A DRY LINE IS NOTED EXTENDING ACROSS PORTIONS OF WESTERN KANSAS. GUIDANCE SUGGESTS THE UPPER TROPOSPHERIC LOW OVER THE NORTHWESTERN CONUS WILL SLOWLY DRIFT NORTHEAST THROUGH THE NEXT 24 HOURS...LIKELY POSITIONING ITSELF OVER NORTHERN MONTANA BY 00Z THURSDAY. AN UPPER TROPOSPHERIC SHORT WAVE IS ALSO EXPECTED TO SWING TO THE SOUTH OF THE LOW AND BEGIN MOVING INTO THE CENTRAL HIGH PLAINS BY 00Z THURSDAY. AT THE SURFACE...THE STATIONARY BOUNDARY MAY BEGIN TO MEANDER SLIGHTLY SOUTHEAST OR NORTHWEST AS AN AREA OF LOW BAROMETRIC PRESSURE ORGANIZES OVER THE CENTRAL HIGH PLAINS...WHICH MAY RESULT IN PERIODIC NORTHWESTERLY LOWER TROPOSPHERIC FLOW OVER WEST/NORTHWESTERN PORTIONS OF OUR CWA DURING THE DAY WEDNESDAY...BUT FOR THE MOST PART LOWER TROPOSPHERIC FLOW IS EXPECTED TO REMAIN FROM THE SOUTH ACROSS MUCH OF OUR CWA THROUGH THE NEXT 24 HOURS. AN OVERALL LACK IN OMEGA SHOULD PROMOTE DRY CONDITIONS ACROSS OUR AREA THIS AFTERNOON AND EVENING. THE HRRR DOES INDICATE SOME VERY ISOLATED CONVECTION OVER WESTERN NEBRASKA LATE THIS AFTERNOON INTO THIS EVENING AS THE CONVECTIVE TEMPERATURE IS REACHED...AND THE 4KM WRF-NMM INDICATES ISOLATED TO SCATTERED CONVECTION OVER SOUTHEASTERN NEBRASKA AND NORTHEASTERN KANSAS FOR THE SAME REASON. SO ALTHOUGH ISOLATED CONVECTIVE ACTIVITY CERTAINLY CANNOT BE RULED ACROSS THE REGION THIS AFTERNOON AND EVENING...THE PROBABILITY OF ANY ONE LOCATION ACTUALLY OBSERVING THIS ACTIVITY IS TOO LOW FOR INSERTION INTO THE FORECAST AND AS A RESULT...WILL MAINTAIN THE DRY FORECAST FOR OUR CWA FOR THIS AFTERNOON AND EVENING. IN THE OFF CHANCE A THUNDERSTORM CAN GET GOING...IT WOULD HAVE 2000-3000J/KG 0-1KM MLCAPE AND ~35KTS DEEP LAYER BULK SHEAR TO WORK WITH...SO CERTAINLY LARGE HAIL AND STRONG THUNDERSTORM WIND GUSTS COULD RESULT...BUT AGAIN THE PROBABILITY OF SUCH ACTIVITY BEING REALIZED TO TOO LOW FOR INSERTION INTO THE FORECAST AND HWO AT THIS TIME. DURING THE OVERNIGHT HOURS TONIGHT...A 60-70KT LOW LEVEL JET AXIS JUST ABOVE THE BOUNDARY LAYER IS EXPECTED TO DEVELOP FROM CENTRAL KANSAS INTO SOUTHEASTERN NEBRASKA. ALTHOUGH THE NORTHWESTERN PERIPHERY OF THIS JET AXIS WILL LIKELY CLIP OUR CWA...IT APPEARS THE BULK OF ANY MOISTURE CONVERGENCE WILL REMAIN TO OUR EAST...AND THE PRIMARY AXIS OF THERMAL ADVECTION WILL REMAIN TO OUR SOUTHEAST. GIVEN ALL THIS...OPTED TO KEEP OUR FORECAST DRY TONIGHT THROUGH THE MORNING HOURS ON WEDNESDAY AS WELL. HEADING INTO WEDNESDAY AFTERNOON...SYNOPTIC-SCALE OMEGA SHOULD INCREASE SOMEWHAT ACROSS THE REGION AS THE UPPER TROPOSPHERIC SHORT WAVE MOVES INTO THE CENTRAL HIGH PLAINS. THIS INCREASING OMEGA...WORKING IN CONCERT WITH LOWER TROPOSPHERIC CONVERGENCE AND FORCING ALONG THE MEANDERING BAROCLINIC ZONE...AS WELL AS NEAR- ZERO CIN ACROSS MUCH OF THE REGION BY LATE AFTERNOON...SHOULD BE SUFFICIENT FOR AT LEAST SOME ISOLATED CONVECTION BY LATE AFTERNOON AND EARLY EVENING. ONE MIGHT THINK LOCATIONS IN THE VICINITY OF THE LOWER TROPOSPHERIC BAROCLINIC ZONE WILL HAVE A BETTER CHANCE AT OBSERVING CONVECTION...BUT QPF FIELDS FROM VARIOUS MODELS SUGGEST OUR SOUTHERN CWA STANDS A BETTER CHANCE AT OBSERVING CONVECTION DUE TO LOWER CIN VALUES. REALLY HARD TO SAY ONE LOCATION HAS A BETTER CHANCE OVER ANOTHER...SO WENT AHEAD AND BLANKETED THE ENTIRE CWA WITH ~20% POPS BETWEEN 21Z WEDNESDAY AND 00Z THURSDAY. SHOULD DEEP CONVECTION BE REALIZED ACROSS THE AREA WEDNESDAY AFTERNOON AND EVENING...0-1KM MLCAPE VALUES OF 2000-3000J/KG ARE EXPECTED TO ACCOMPANY DEEP LAYER BULK SHEAR VALUES OF 20-30KTS. GIVEN ALL THIS...WILL GO AHEAD AND CONTINUE TO OUTLOOK THE AREA FOR ISOLATED SEVERE WEATHER STARTING LATE WEDNESDAY AFTERNOON. LITTLE CHANGE IN THE LOWER TROPOSPHERIC AIR MASS WILL PROMOTE SIMILAR TEMPERATURE READINGS TONIGHT WHEN COMPARED TO EARLY THIS MORNING...WITH OVERNIGHT LOWS IN THE 60S TO NEAR 70 CURRENTLY FORECAST ACROSS THE CWA. SIMILAR TEMPERATURE READINGS ARE ALSO EXPECTED WEDNESDAY WHEN COMPARED TO TODAY...WITH WEDNESDAY AFTERNOON HIGHS IN THE 90S CURRENTLY EXPECTED. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 315 PM CDT TUE JUN 17 2014 MAIN FORECAST CONCERNS WILL BE CHANCES FOR THUNDERSTORMS THROUGH MUCH OF THE PERIOD AND TEMPERATURES THROUGH THE PERIOD. A COLD FRONT IS EXPECTED TO MOVE MOST OF THE WAY THROUGH THE FORECAST AREA WEDNESDAY NIGHT. THUNDERSTORMS ARE EXPECTED TO CONTINUE TO DEVELOP ALONG THE FRONT DURING THE EVENING WITH MORE THUNDERSTORMS MOVING THROUGH THE AREA DURING THE NIGHT AS THE UPPER LEVEL WAVE MOVES INTO THE AREA. THE BEST MUCAPE DURING THIS PERIOD WILL BE DURING THE EVENING HOURS...THEN DIMINISHING LATE WEDNESDAY NIGHT...SO EXPECT ANY SEVERE WEATHER TO BE MAINLY DURING THE EVENING HOURS. THE FRONT LINGERS JUST TO THE EAST THURSDAY MORNING AND PRECIPITATION COULD LINGER INTO THE MORNING HOURS IN THE EAST...BUT THEN AS ANOTHER UPPER LEVEL WAVE MOVES INTO THE AREA DURING THE AFTERNOON THUNDERSTORMS COULD DEVELOP ALONG THE FRONT AND SOME OF THEM COULD BE IN THE EASTERN PART OF THE FORECAST AREA. MOST OF THE AREA WILL BE DRY MOST OF THE DAY. THERE IS GENERALLY NORTHWEST FLOW ACROSS THE AREA DURING THE PERIOD...WITH SEVERAL UPPER LEVEL WAVES THAT MOVE THROUGH. EACH OF THE WAVES BRING THE CHANCE FOR SOME THUNDERSTORMS TO THE AREA. IT CERTAINLY WILL NOT BE RAINING ALL OF THE TIME OVER ALL OF THE AREA...BUT THERE IS A CHANCE. MOST OF THESE ARE PRETTY SMALL CHANCES SINCE THE MODELS HAVE SLIGHT DIFFERENCE IN THE TIMING OF EACH OF THE WAVES. THE BEST CHANCES FOR THUNDERSTORMS WILL BE SATURDAY NIGHT AND SUNDAY NIGHT WHEN THE STRONGEST OF THE UPPER LEVEL WAVES WILL BE MOVING THROUGH. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1227 AM CDT WED JUN 18 2014 VFR CONDITIONS REMAIN IN THE FORECAST THROUGH THIS TAF PERIOD. MODELS/GUIDANCE IN GOOD AGREEMENT KEEPING THE MAJORITY OF THE PERIOD WITH S/SWRLY WINDS...WHICH WILL AGAIN HAVE THE POTENTIAL TO BE ON THE GUSTY SIDE DURING THE DAYTIME HOURS. EXPECTING SKIES TO REMAIN MOSTLY CLEAR TONIGHT...WITH INCREASING CLOUDS THROUGH THE REST OF THE PERIOD EXPECTED TO BE IN MID/UPPER LEVELS. SOME MODELS HINT AT THE CHANCE FOR SOME THUNDERSTORM ACTIVITY TO DEVELOP LATE IN THE PERIOD...AND HAVE INSERTED A VC MENTION. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ SHORT TERM...BRYANT LONG TERM...JCB AVIATION...ADO
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1229 AM EDT WED JUN 18 2014 .SYNOPSIS... CENTRAL PA WILL REMAIN ON THE NORTHERN PERIPHERY OF A SUBTROPICAL RIDGE CENTERED OVER THE SOUTHEAST STATES THROUGH AT LEAST WEDNESDAY. SLIGHTLY COOLER AND DRIER AIR IS EXPECTED TO WORK INTO THE AREA FOR THE LATTER PART OF THE WEEK. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... SEVERE THUNDERSTORM WATCH 314 HAS EXPIRED...AND WE`RE DEALING WITH A DISSIPATING LINE OF STORMS NUDGING INTO A MID-LEVEL CAP ACROSS THE SOUTHERN HALF OF PA WILL SLOWLY SAG SOUTH/WEAKEN OVERNIGHT ALLOWING THE TSRA TO MAKE IT AS FAR SOUTH /ALBEIT IN A SLIGHTLY WEAKENED STATE/ AS THE INTERSTATE 80 CORRIDOR AFTER 06Z. A FEW ISOLATED TSRA SHOULD LINGER ACROSS THE NW 2/3RDS OF THE CWA OVERNIGHT...WHILE THE FAR SE ZONES SEE CLEAR TO PARTLY CLOUDY SKIES. IT WILL BE ANOTHER VERY MUGGY OVERNIGHT. LOWS WELL UP IN THE 60S WILL BE SOME 10-15 DEG ABOVE NORMAL. && .SHORT TERM /6 AM THIS MORNING THROUGH 6 PM THURSDAY/... LOW LEVEL NW FLOW ON WEDNESDAY WILL INITIALLY BRING SLIGHTLY DRIER AIR INTO THE REGION...BUT A RETURN SOUTHERLY FLOW IS MADE TO RAPIDLY REDEVELOP BY AFTERNOON OVER OVER WESTERN AREAS. SHORT RANGE MODEL SURFACE PRESSURE PROGS SUGGEST WE WILL BE BASICALLY IN A COL BETWEEN LOW PRESSURE EAST AND WEST OF US...AND HIGH PRESSURE NORTH AND SOUTH. MODELS ONCE AGAIN GENERATE A RESPECTABLE AMOUNT OF INSTABILITY SO MORE DIURNALLY FAVORED CONVECTION SHOULD BE IN STORE. THE IMPLIED PRESENCE OF A LOW LEVEL BOUNDARY OVER SWRN PA SUGGESTS THAT THE BEST CHANCE OF SHOWERS WILL WEST...WITH LESSER CHANCES FURTHER EAST. TEMPERATURES MAY BE A DEGREE OR TWO COOLER THAN TODAY...NOT SIGNIFICANTLY DIFFERENT. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... UPPER RIDGE CURRENTLY OVER THE EASTERN U.S. IS FORECAST TO BE SQUASHED BY AN UPPER LOW FORECAST TO DEEPEN OVER EASTERN QUEBEC MIDWEEEK AND DIG INTO THE CANADIAN MARITIMES BY THE WEEKEND. THIS UPPER LOW WILL PUSH A COLD FRONT SOUTHWARD INTO THE AREA DURING THE LATTER HALF OF THE WEEK...BRINGING AN END TO THE SULTRY TEMPS. THE FRONT IS FCST TO STALL JUST SOUTH OF PA AND SERVE AS A POSSIBLE FOCUS FOR CONVECTION. SEVERAL SHORTWAVES TRAVELING THROUGH THE UPPER FLOW WILL PRODUCE A SERIES OF SFC WAVES ALONG THE FRONT AS IT LIFTS NORTH AS A WARM FRONT AT SOME POINT OVER THE WEEKEND INTO EARLY NEXT WEEK. THIS LOOKS TO SUPPORT AN UNSETTLED PATTERN...THOUGH CERTAINTY OF PCPN ON ANY GIVEN DAY REMAINS IN THE CHANCE CATEGORY GIVEN THE TIME FRAME AND UNCERTAINTY IN THE OVERALL PATTERN. && .AVIATION /04Z WEDNESDAY THROUGH SUNDAY/... BROKEN LINE OF STRONG TO SEVERE TSRA AT 02Z TRACKING ESE FROM NWRN PENN...WILL IMPACT KBFD THROUGH 04Z BEFORE PUSHING EASTWARD AND SOUTHWARD TOWARD KELM-KDUJ. THOUGH MID-LEVEL CAP INCREASES AS ONE HEADS SOUTHWARD...THIS LINE WILL CONTINUE TO SAG SLOWLY SOUTHWARD AFTER MIDNIGHT...ALLOWING THE TSRA TO APPROACH KFIG-KUNV-KIPT AFTER 06Z. THE LINE WILL CONTINUE TO WEAKEN FURTHER AFTER THAT...WITH POTENTIAL FOR SCT SHOWERS FROM KJST-KAOO AND POSS A TSTM AROUND 08-10Z IN VICINITY OFF KMDT-KLNS IF THE MESOSCALE HRRR MODEL HOLDS TRUE /BUT DIDNT MENTION THAT IN TAFS JUST YET WITH FAIR AMOUNT OF UNCERTAINTY IN BOTH STRENGTH AND LOCATION 6+ HRS OUT/. OTHERWISE OVERNIGHT...WARM AND HUMID CONDITIONS CONTINUE. BEHIND THE LINE OF STORMS MAINLY ACROSS THE NW MTNS...SHOULD SEE A LOWER DECK OF MVFR STRATOCU DEVELOP. OTHERWISE NO WIDESPREAD REDUCTIONS ARE EXPECTED. WEDNESDAY SHOULD REMAIN FAIRLY QUIET THROUGH THE FIRST HALF...BUT WARM AND HUMID AIRMASS WILL AGAIN PROVIDE ENOUGH INSTABILITY TO KICK OFF MAINLY AFTERNOON CONVECTION THAT WILL LINGER INTO THE EVENING HOURS. MOST NUMEROUS SHOWERS/TSTMS WILL BE IN THE SW...WITH SCATTERED CONVECTION DEVELOPING ELSEWHERE...ALL PROVIDING LOCAL REDUCTIONS. OUTLOOK... THU...VFR WITH AREAS OF MVFR AND SCT SHOWERS/TSTMS. FRI...NO SIG WX. SAT-SUN...VFR WITH AREAS OF MVFR AND SCT SHOWERS/TSTMS. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE/LAMBERT NEAR TERM...DEVOIR/LAMBERT SHORT TERM...LA CORTE LONG TERM...GARTNER/MARTIN AVIATION...RXR
AREA FORECAST DISCUSSION
NWS PORTLAND OR
240 AM PDT WED JUN 18 2014 .SYNOPSIS...AN UPPER LEVEL CLOSED LOW WAS CENTERED OVER IDAHO EARLY THIS MORNING AND WILL CONTINUE MOVING EAST TODAY. A BRIEF UPPER LEVEL RIDGE WILL MOVE INTO THE PACIFIC NORTHWEST TODAY FOR DRIER AND WARMER WEATHER THAT WILL GENERALLY LAST INTO THURSDAY. THE NEXT FRONT WILL APPROACH THE SOUTH WASHINGTON AND NORTH OREGON COAST LATER THURSDAY THEN INLAND THURSDAY NIGHT AND INTO FRIDAY FOR INCREASING ONSHORE FLOW AND ANOTHER CHANCE OF LIGHT SHOWERS. THEN EXPECT A TYPICAL ONSHORE FLOW PATTERN NEXT WEEKEND INTO EARLY NEXT WEEK WITH A LARGE SCALE TROUGH OVER THE NORTHEAST PACIFIC THAT WILL PRODUCE SOUTHWEST FLOW ALOFT OVER THE PACIFIC NORTHWEST... MAINTAINING ONSHORE FLOW FOR RATHER PERSISTENT LOW CLOUDS ALONG THE COAST AND AN OVERNIGHT AND MORNING MARINE STRATUS REGIME INLAND. && .SHORT TERM...THE UPPER LOW THAT BROUGHT UNSETTLED AND COOL WEATHER TO SOUTHWEST WASHINGTON AND NORTHWEST OREGON THE LAST FEW DAYS WAS CENTERED IN IDAHO EARLY THIS MORNING AND WILL CONTINUE TO MOVE EAST AND AWAY FROM OUR FORECAST AREA TODAY. THE RESIDUAL ONSHORE FLOW HAS A COMPLICATED LOW CLOUD PATTERN OVER THE FORECAST AREA THIS MORNING...WITH STRATOCUMULUS BANKED UP AGAINST THE CASCADES AND FOOTHILLS AND INTO THE EASTERN PART OF THE VALLEYS. THERE IS ANOTHER AREA OF LOW CLOUDS ALONG THE NORTH COAST WITH A BIT LOWER CIGS. IT NOW APPEARS THE GAP BETWEEN THESE TWO BANKS OF CLOUDS WILL FILL IN QUITE A BIT THIS MORNING...EXCEPT PERHAPS ALONG THE CENTRAL COAST WHERE ONLY PATCHY LOW CLOUDS OR FOG ARE EXPECTED. THE MODELS STILL PAINT A TOUCH OF QPF THIS MORNING MAINLY ALONG THE CASCADES AND THE NORTH COAST...AND CANNOT RULE IT OUT BUT ANYTHING THAT FALLS SHOULD BE RATHER MINOR. WITH A SHORT WAVE UPPER RIDGE MOVING IN TODAY THE CLOUDS SHOULD CLEAR AS WE GET A WAYS INTO THE AFTERNOON...EXCEPT PERHAPS ON THE NORTH COAST. TEMPS WILL HAVE A CHANCE TO REACH 70 TODAY INLAND. THE MODELS ARE FORECASTING A LONG WAVE TROUGH TO SET UP OFF THE COAST OVER THE NORTHEAST PACIFIC TONIGHT AND THURSDAY THAT WILL PERSIST INTO NEXT WEEK. THIS WILL PRODUCE A SOUTHWEST FLOW ALOFT THAT IS USUALLY PRETTY GOOD AT MAINTAINING A RATHER PERSISTENT MARINE LAYER ALONG THE COAST THAT SPREADS INLAND IN THE NIGHT AND MORNING HOURS. THE FIRST LITTLE DISTURBANCE ROTATING AROUND AND OUT OF THE LONG WAVE TROUGH MAY BRUSH THE SOUTH WASHINGTON COAST TO NEAR ASTORIA WILL A LITTLE DRIZZLE LATE TONIGHT AND THURSDAY. INLAND AREAS WILL SEE SOME MORNING LOW CLOUDS THURSDAY OTHERWISE MORE SUNSHINE AND WARMER TEMPS INTO THE MID 70S. THE NEXT SYSTEM IS A WEAKENING FRONT THAT CONTINUES TO BE FORECAST TO MOVE ONSHORE THURSDAY NIGHT AND ACROSS THE FORECAST AREA EARLY FRIDAY. THIS SHOULD BRING MORE PERSISTENT CLOUDY CONDITIONS TO THE AREA...WITH A FEW LIGHTER SHOWERS AS WELL. TOLLESON .LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS... FRIDAY NIGHT THROUGH MONDAY...EXPECT LITTLE VARIATION IN THE WEATHER OVER THE EXTENDED PORTION OF THE FORECAST. THE UPCOMING WEEKEND AND FIRST HALF OF NEXT WEEK WILL DOMINATED BY A LONG WAVE UPPER LEVEL TROUGH OVER THE NORTHEAST PACIFIC. PERIODIC SHORT WAVES ROTATING AROUND THE LOW WILL BRING REINFORCING SHOTS OF MARINE AIR...BUT AT THIS POINT LITTLE OR NO PRECIPITATION IS EXPECTED. EXPECT A TYPICAL ONSHORE FLOW PATTERN OF OVERNIGHT AND MORNING MARINE STRATUS PUSHES FOLLOWED BY PARTIAL AFTERNOON CLEARING. TEMPS WILL LIKELY REMAIN NEAR SEASONAL NORMALS. PYLE && .AVIATION...TWO LAYERS OF CLOUDS AFFECTING THE AREA THIS MORNING. ONE BANKING UP AGAINST THE CASCADES AND BACK FILLING OVER PARTS OF THE INTERIOR LOWLANDS IS AROUND 4000 FT. ANOTHER LAYER IS PUSHING INLAND FROM THE COASTAL WATERS WITH CIGS AROUND 3000 FT. MAY SEE SOME OF THE MVFR CIGS AFFECT LOWER COLUMBIA TO THE KPDX ARE FOR A FEW HOURS...14Z TO 17Z WED. GENERAL TREND IS FOR CLOUDS TO DISSIPATE AFTER MIDDAY. MUCH OF THE SOUTH COAST AND SOUTH INTERIOR TO NEAR KEUG REMAIN CLR-SCT AND WILL LIKELY REMAIN SO TODAY. ONSHORE FLOW CONTINUES TONIGHT AND LOOKS LIKE THE MARINE STRATUS WILL FILL IN ON THE COAST WITH CIGS IN THE 1500-2500 FT RANGE AND WILL HAVE LIMITED INLAND INTRUSION. KPDX AND APPROACHES...VFR CONDITIONS PREVAILING TODAY AND TONIGHT. HOWEVER...THERE IS CERTAINLY A DECENT CHANCE AN MVFR DECK AROUND 2500 FT BETWEEN 13Z AND 17Z WED. && .MARINE...VERY FEW CHANGES THROUGH THE WEEKEND AS RELATIVELY BENIGN WINDS AND SEAS DOMINATE. HIGH PRES DOMINATES THE NE PACIFIC THROUGH THERE ARE WEAK FRONTS WEAKENING THE HIGH PRES OVER THE WATERS TODAY. A STRONGER FRONT PUSHES INTO THE WATERS LATER THU AFTERNOON AND EVENING. && .PQR WATCHES/WARNINGS/ADVISORIES... OR...NONE. WA...NONE. PZ...NONE. && $$ MORE WEATHER INFORMATION ONLINE AT... HTTP://WEATHER.GOV/PORTLAND INTERACT WITH US VIA SOCIAL MEDIA WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.PORTLAND.GOV WWW.TWITTER.COM/NWSPORTLAND THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY REFERRED TO AS THE FORECAST AREA.
  [top] Area Forecast Discussion National Weather Service Spokane WA 217 AM PDT WED JUN 18 2014 .SYNOPSIS... Light rain will continue over the Idaho Panhandle and extreme eastern Washington through this morning. A drying trend will begin this afternoon with only a few lingering showers over the Panhandle tonight. Warmer...drier and more summer-like conditions will envelop the region for the rest of the week with a small chance of afternoon thunderstorms mainly over the mountains through the weekend. && .DISCUSSION... Wednesday: A deep low pressure system currently spinning over southwestern Montana will begin to track east this afternoon. The steady stream of moisture and vort max`s wrapping around its backside will finally get pulled east of the ID/MT border and rain will come to an end today following almost 24-30 hours of straight rainfall. This will be a rather slow drying trend with steady rain likely to linger through much of the morning before giving way to scattered light showers during the afternoon hours. 2AM radar and satellite confirms two last vorticity maximums will pass through the Inland NW before the storm system drifts east. One is driving moderate rains across SE WA while a second is making its way into Nrn ID from NW Montana. Timing utilizing the HRRR and satellite extrapolation suggest steady rain will end in the north (NE WA/Nrn ID) around 8AM and south (Palouse, Blues, L-C Valley, Camas Prairie) roughly 11AM. Confidence is not as high for the Central Panhandle Mtns of ID, especially along the immediate MT border which looks be clipped by one last wave of moisture during the afternoon hours. As the steady precipitation ends, sunbreaks will help destabilize the atmosphere promoting a renewed threat for showers. 500mb warming suggest any convection will be shallow but given the saturated boundary layer now in place, it even shallow convection could yield another tenth of an inch. May even get a stray thunderstorm across the northeastern mountains. Weak high pressure will begin building into the region Wednesday night and continue on Thursday. There is a good possibility that fog forms in the northeastern valleys of WA and Nrn ID after these soaking rains but coverage is still somewhat uncertain due to a light push of w/sw winds behind today`s storm system and possibility for lingering cloud cover. Spring will return to the Inland NW on Thursday under the shortwave ridging. There should be a good deal of sunshine in the morning giving way to fair afternoon cumulus and temperatures will return to seasonal normals. /sb Thursday night through Sunday...Model agreement is decent and consistent in placing the forecast area in a sustained southwest flow regime under the southeast flank of a stationary Gulf of Alaska closed low. This pattern typically argues for generally dry conditions in the basin with a small chance of afternoon and evening thunderstorms over the mountains north and east of the basin. There do not appear to be any significant waves or disturbances forecast as of yet that would bring a chance of more widespread thunderstorms during this period. Confidence is high that a warming trend will occur during this period...but not too warm since the southwest flow has a significant westerly component to shunt the hot air mass to the south of the region off to the east rather than pumping it northward into the forecast area. All in all a rather benign early summer weather regime is expected from Thursday through Sunday with a small chance of mountain thunderstorms especially in the Blues and Idaho Panhandle. /Fugazzi Sunday night through Tuesday night: Region remains in southwesterly flow throughout the period allowing for increased moisture to make it into the region. Along with the moisture, warm air will also accompany the flow bringing temps well above normal throughout the early part of the week. Weak waves of energy will pass through from SW to NE, but with limited forcing from any significant features mountain showers and isolated t-storms look to remain the extent of precip chances. The most notable feature comes through Tuesday, but even this currently is tough to get excited about as it is lacking overall dynamics. Even with models showing precipitable water values near an inch, without the trigger for showers the forecast currently looks pretty dry for most. For valley locations, the most likely changes noticed from the passing waves will be increased mid and high level clouds with maybe a stray shower. The most significant feature from the SW flow will be the warm temperatures. Monday currently looks to be the warmest with valley highs in the mid 80s to lower 90s. Even with a slight cool down on Tuesday, highs still remain 5 or so degrees above normal. /Fliehman && .AVIATION... 06z TAFS: Wrap moisture moisture will continue to move into the eastern third of WA and N Idaho on the back side of a low pressure system. This will keep a continuation of light to moderate rain at KGEG/KSFF/KCOE/KPUW/KLWS...decreasing between 12-18z Wednesday as the low begins to pull away from the region. A very moist boundary layer along with light low level upslope flow into the higher terrain of the Palouse, Spokane/Coeur D`Alene area should result in lowering CIGS overnight with IFR conditions expected. However areas of heavier rainfall will result in brief improvement to VFR CIGS. Then as precip decreases Wednesday morning and drier air invades from the west...CIGS will respond with VFR conditions expected Wed afternoon. KMWH and KEAT will be much less affected with VFR conditions likely to persist through 00z Thursday. JW && .PRELIMINARY POINT TEMPS/POPS... Spokane 65 49 76 52 79 54 / 60 10 0 0 0 10 Coeur d`Alene 62 47 74 49 78 51 / 60 20 0 0 0 10 Pullman 65 45 74 47 78 49 / 100 10 0 0 0 10 Lewiston 71 52 83 55 87 57 / 100 10 0 0 10 10 Colville 69 49 78 49 80 49 / 40 20 0 0 10 0 Sandpoint 60 45 73 45 77 48 / 50 30 10 0 10 0 Kellogg 59 46 72 48 76 52 / 100 30 10 0 10 20 Moses Lake 79 53 84 56 86 55 / 10 0 0 0 0 10 Wenatchee 81 57 84 60 86 57 / 10 0 0 0 0 10 Omak 81 52 86 54 84 52 / 10 0 0 10 10 10 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1111 PM CDT TUE JUN 17 2014 UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE .SHORT TERM...TONIGHT AND WEDNESDAY ISSUED AT 238 PM CDT TUE JUN 17 2014 LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW LOW PRESSURE ASSOCIATED WITH LAST NITES CONVECTION MOVING EAST ACROSS LAKE HURON. A CONVECTIVE OUTFLOW BOUNDARY EXTENDS FROM THIS SURFACE LOW ACROSS NORTHERN ILLINOIS AND CENTRAL IOWA WHERE CUMULUS CLOUDS LOOK AGITATED. INSTABILITY HAS BEEN BUILDING THROUGH THE DAY OVER SOUTHWEST MINNESOTA AND SOUTHERN IOWA BUT CONSIDERABLE CONVECTIVE INHIBITION IS PREVENTING THE NEXT THUNDERSTORM COMPLEX FROM DEVELOPING SO FAR. FARTHER WEST...A SHORTWAVE TROUGH IS MOVING NORTHEAST OVER NEBRASKA WHERE WEAK LOW PRESSURE RESIDES. ACROSS NORTHERN WISCONSIN...CU IS BUILDING OVER NE WISCONSIN WHERE LOW LEVEL CONVERGENCE IS OCCURRING BUT PLENTY OF INHIBITION IS PRESENT THERE AS WELL. WITH THE NEXT THUNDERSTORM COMPLEX ANTICIPATED TO DEVELOP OVER THE NORTHERN MISSISSIPPI VALLEY THIS EVENING...THE THREAT OF SEVERE STORMS REMAINS THE MAIN FORECAST CONCERN. TONIGHT...A SHORTWAVE TROUGH OVER THE CENTRAL PLAINS WILL LIFT NORTHEAST TOWARDS THE NORTHERN MISSISSIPPI VALLEY THIS EVENING AND INTO THE WESTERN GREAT LAKES OVERNIGHT. THE APPROACH OF THE SHORTWAVE COMBINED WITH LIFT ON THE NOSE OF THE LLJ AND DESTABILIZATION OF THE MID-LEVELS SHOULD LEAD TO A THUNDERSTORM COMPLEX DEVELOPING OVER SOUTHERN MINNESOTA AND NORTHERN IOWA LATER THIS AFTERNOON OR EARLY THIS EVENING. THE LATEST NUMERICAL GUIDANCE SHOWS A VARIETY OF TRACKS OF THIS COMPLEX WITH THE NAM/ECMWF TRACKING IT TOWARDS NORTHERN ILLINOIS...WHILE THE MESOMODELS EXPANDING IT TOWARDS MILWAUKEE. SINCE THE LLJ AND ELEVATED INSTABILITY WILL BE DIRECTED TOWARDS SOUTHERN WISCONSIN AND NORTHERN ILLINOIS...A SOUTHEAST TRACK SEEMS MORE PROBABLE. HOWEVER...SOME THUNDERSTORMS MAY STILL MOVE INTO CENTRAL AND EAST-CENTRAL WISCONSIN LATE THIS EVENING AND OVERNIGHT WITH THE APPROACH OF THE SHORTWAVE TROUGH. ELEVATED INSTABILITY WILL BE AROUND 1K-1.5K J/KG WHILE EFFECTIVE BULK SHEARS WILL BE APPROX. 30 KTS. SO APPEARS THAT A LOW END SEVERE THREAT IS STILL POSSIBLE...IF THE MAIN COMPLEX DOES NOT CUT OFF MOISTURE INFLOW FROM THE SOUTH. HEAVY RAIN WILL BE ALSO POSSIBLE SOUTH OF ROUTE 29 WHERE PWATS WILL BE UPWARDS OF 1.5 INCHES. LOWS IN THE UPPER 50S NORTH TO MIDDLE 60S SOUTH. WEDNESDAY...THE SHORTWAVE TROUGH WILL BE EXITING EASTERN WISCONSIN DURING THE MORNING WHICH WILL KEEP THE CHANCE OF SHOWERS AND STORMS GOING THROUGH THE AM HOURS OVER CENTRAL AND NORTHEAST WISCONSIN. THINK PRECIP WILL BE EXITING BY LATE IN THE MORNING AND THEN WINDS WILL SHIFT TO THE NORTHEAST WHICH WILL BRING IN COOLER AIR OFF THE GREAT LAKES. EVEN THOUGH THE 850MB BOUNDARY WILL STALL OUT OVER SOUTHERN WISCONSIN....AM THINKING THAT THE COOLER AND MORE STABLE AIR WILL KEEP PRECIP CHANCES SMALLER THAN THE CURRENT FORECAST SHOWS. HIGHS RANGING FROM THE MID 70S EAST TO LOW 80S WEST...COOLER LAKE SIDE. .LONG TERM...WEDNESDAY NIGHT THROUGH TUESDAY ISSUED AT 238 PM CDT TUE JUN 17 2014 CONVECTIVE POTENTIAL WEDNESDAY NIGHT INTO THE WEEKEND CONTINUES TO BE THE MAIN CONCERN. EARLY IN PERIOD MODELS ALL TRENDING TOWARD PUSHING PCPN OFF TO THE WEST...WITH EAST WINDS OUT OF SURFACE HIGH OVER HUDSON BAY FILTERING IN DRIER AIR OVER THE REGION. PCPN CHANCES INCREASE AGAIN THU NIGHT/FRI AS LOW AND SURFACE TROF SHIFT EAST. NOT OVERLY IMPRESSED WITH CHANCES FOR SEVERE AT THIS TIME WITH WEAK LLVL JET AND SHEAR. PLENTY OF MOISTURE REMAINS OVER REGION WITH MAIN ISSUE AGAIN CHANCE FOR HEAVY RAIN. TEMPERATURES TO REMAIN AT OR ABOVE NORMAL. WEAKENING UPPER LOW WILL MOVE INTO THE WESTERN GREAT LAKES REGION OVER THE WEEKEND...LINGERING INTO EARLY NEXT WEEK. PCPN CHANCES TO CONTINUE. && .AVIATION...FOR 06Z TAF ISSUANCE ISSUED AT 1111 PM CDT TUE JUN 17 2014 THUNDERSTORMS ARE LIKELY ACROSS MUCH OF CENTRAL AND NORTHERN WISCONSIN OVERNIGHT WITH MVFR AND LOCAL IFR CONDITIONS. WHATEVER ACTIVITY IS LEFT EARLY WEDNESDAY SHOULD EXIT BY MIDDAY WITH MVFR OR VFR CONDITIONS WEDNESDAY AFTERNOON. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....MPC LONG TERM......TE AVIATION.......RDM
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
606 AM EDT WED JUN 18 2014 .SYNOPSIS... HIGH PRESSURE WILL BE CENTERED SOUTH AND EAST OF THE FORECAST AREA THROUGH THE WEEKEND. A WEAK TROUGH IN THE FORECAST AREA WILL BECOME MORE PRONOUNCED OVER THE WEEKEND. HIGH PRESSURE ALOFT WILL BEGIN TO WEAKEN FRIDAY. THE PATTERN SUPPORTS ABOVE NORMAL TEMPERATURES. ISOLATED MAINLY AFTERNOON AND EVENING THUNDERSTORMS WILL OCCUR TODAY AND THURSDAY. SOMEWHAT GREATER THUNDERSTORM COVERAGE WILL OCCUR OVER THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... THE SURFACE RIDGE WILL REMAIN SOUTH AND EAST OF THE FORECAST AREA. ALOFT...THE PRESSURE RIDGE WILL CONTINUE. CONVERGENCE ASSOCIATED WITH A WEAK LEE-SIDE TROUGH AND ALONG THE SEA-BREEZE FRONT...A WEAK SHORTWAVE TROUGH CAUGHT IN THE H5 RIDGE...PLUS STRONG HEATING MAY HELP SUPPORT THUNDERSTORMS. HOWEVER...EXPECT JUST ISOLATED COVERAGE BECAUSE OF SHALLOW MOISTURE AND GENERAL UPPER RIDGING. THE 07Z HRRR DISPLAYS JUST ISOLATED COVERAGE THIS AFTERNOON IN THE EXTREME NORTHWEST PART OF THE FORECAST AREA. THE GFS AND NAM MOS POPS ARE MAINLY 10 PERCENT OR LESS. THE TEMPERATURE GUIDANCE WAS CLOSE BUT MAY BE A LITTLE TOO COOL... ESPECIALLY WITH THE LOW TEMPERATURES. THE GUIDANCE HAS TRENDED WITH A COOL BIAS...BUT HAS BEEN CLOSER THE PAST COUPLE OF DAYS. HAVE GENERALLY USED THE HIGH TEMPERATURE GUIDANCE AND WENT A FEW DEGREES ABOVE THE LOW TEMPERATURE GUIDANCE. && .SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/... SURFACE HIGH PRESSURE WILL CONTINUE SOUTH AND EAST OF THE FORECAST AREA. THE UPPER RIDGING WILL CONTINUE. STRONG HEATING AND CONVERGENCE INTO A LEE-SIDE TROUGH AND ALONG THE SEA-BREEZE FRONT MAY HELP SUPPORT THUNDERSTORMS BUT EXPECT LITTLE COVERAGE BECAUSE OF SHALLOW MOISTURE AND THE UPPER RIDGING. THE NAM AND GFS MOS ARE CONSISTENT WITH VERY LOW POPS. USED THE WARMER TEMPERATURE GUIDANCE BECAUSE OF THE RECENT COOL BIAS. && .LONG TERM /FRIDAY THROUGH TUESDAY/... THE GFS AND ECMWF DISPLAY THE UPPER RIDGE WEAKENING FRIDAY AND SATURDAY. A SURFACE TROUGH IN THE FORECAST AREA APPEARS TO BECOME MORE DOMINATE. THE PATTERN SUPPORTS ABOVE NORMAL TEMPERATURES AND SCATTERED MAINLY AFTERNOON AND EVENING THUNDERSTORMS. THE GFS ENSEMBLE MEAN SUPPORTS A POP AROUND 20 PERCENT FRIDAY...AND 30 PERCENT DURING THE REST OF THE MEDIUM-RANGE PERIOD. THE GFS...ECMWF...AND EKD MOS ALSO GENERALLY SUPPORTED THESE POPS. MOST OF MOS HAS TEMPERATURES REMAINING ABOVE CLIMATOLOGY DURING THE PERIOD. && .AVIATION /10Z WEDNESDAY THROUGH SUNDAY/... LITTLE CHANGE IN THE OVERALL WEATHER PATTERN EXPECTED THROUGH THE TAF PERIOD...SO WILL CONTINUE WITH PERSISTENCE. UPPER RIDGE IN THE VICINITY...WITH SURFACE RIDGE AXIS TO OUR SOUTH AND TROUGH TO OUR NORTH. MVFR/BRIEF IFR FOG POSSIBLE AT AGS AND OGB UNTIL AROUND 13Z THIS MORNING. BETTER MOISTURE TO THE NORTH WILL PROVIDE BETTER DIURNAL CONVECTIVE COVERAGE MAINLY NORTH OF THE TERMINALS LATER THIS AFTERNOON AND EVENING...SO CHANCE OF TSRA AFFECTING TERMINALS TOO LOW TO INCLUDE IN THE TAFS AT THIS TIME. EXTENDED AVIATION OUTLOOK...LITTLE CHANGE THURSDAY. EARLY MORNING FOG POSSIBLE...MAINLY AT FOG PRONE SITES AGS/OGB...WITH ISOLATED AFTERNOON THUNDERSTORMS MAINLY NORTH OF THE TERMINALS. BETTER CHANCE OF DIURNAL THUNDERSTORMS FRIDAY THROUGH SUNDAY AS UPPER RIDGE GIVES WAY TO UPPER TROUGH...AND SURFACE TROUGH WITH BETTER MOISTURE SLIPS SOUTH INTO THE REGION. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$ Area Forecast Discussion National Weather Service Lincoln IL 1055 AM CDT Wed Jun 18 2014 .DISCUSSION... ISSUED 1045 AM CDT Wed Jun 18 2014 A line of storms has reached Knox county and will be moving into an unstable airmass with decreasing CIN and CAPE values approaching 3000 J/kg. Expect the line to move primarily east as individual storms drift southeast. Based on HRRR 3km and NCEP 4km output, it appears the southern extent of the line as it progresses east should generally remain north of a line from Rushville to Lincoln to Champaign. We kept daytime chance PoPs confined to that general area. That line it projected to remain sub-severe for the most part during the day. Severe potential looks higher tonight as a complex of storms develops to our north along the stationary front and rides over the upper level ridge into N IL this evening. That complex is projected to curve to the ESE tonight and dissipate as it reaches Lincoln to Champaign shortly after midnight. Varying solutions high resolution models lead to lower confidence on any one solution, but that appears to be closer to the consensus at this point. Temperatures today will climb into the lower 90s in most areas. The current line of storms will produce a cold pool that will spread across the northern third of counties, but some sun later this afternoon should boost even those areas back toward the low 90s. Dewpoints will reside in the low 70s all day as well, making for very humid conditions. Heat index readings will approach 100 degrees in areas that remain sunny through the day, mainly south of Lincoln. Updates this morning were mainly to the weather and PoP grids, with minor adjustments to temps. Updated info will be available shortly. Shimon && .AVIATION... ISSUED 637 AM CDT Wed Jun 18 2014 A very challenging forecast, as convection will be dictated by various residual outflow boundaries plus a surface front across northern Illinois that may drift south a bit tonight. With the various synoptic and high-resolution models showing a wide variety of solutions, confidence on thunder elements of the TAF set is lower than usual. Have generally gone with VCTS mentions with a PROB30 group this evening to try and highlight a more likely time frame of any temporary MVFR conditions, based on the output of the ARW and NMM models. Kept KSPI/KDEC dry into early evening, but isolated showers/storms may occur earlier as well. Geelhart && .PREV DISCUSSION... ISSUED 330 AM CDT Wed Jun 18 2014 SHORT TERM...Today through Friday night Will issue another special weather statement to address the heat and humidity today and Thursday with highs around 90F and heat indices peaking from 95 to 100F similar to what we experienced yesterday. Strong upper level ridge (592 dm 500 mb high pressure over the southeast states) has been keeping much of central and southeast IL dry with the heat and humidity. MCS`s bringing more strong to severe thunderstorms with heavy rains north of IL over MN/WI and northern IA early this morning. These MCS`s forming on nose of low level jet interacting with frontal boundary draped over southern Great Lakes and upper MS river valley and extends to 999 mb low pressure in NE CO. Strong 558 dm 500 mb low was along the ID/MT border with series of MCS east of it from SD into the southern Great Lakes. Upper level low near ID/MT border to lift NE into southern Saskatchewan by sunset Thu while short waves to weaken top of upper level ridge and increase chances of convection over central IL from north to south from this afternoon through next few days as frontal boundary sags back south toward central IL by Friday. Most areas will still be dry this morning with isolated convection developing in the tropical air mass this afternoon especially northern areas. RAP and HRRR models also show some qpf in far SE IL from Lawrenceville SE this afternoon. SPC has shifted slight risk of severe storms further south tonight to included most of central IL with just southern six counties not in slight risk. Highest risk of severe storms still appears north of Peoria where 30% risk of large hail and damaging wind gusts where best bulk shear in combination with moderate to strong instability. Highest convection chances of 50-60% over northern counties from tonight through Thu night shift further south during Friday with frontal boundary. SPC keeps slight risk NW of CWA Thu afternoon & Thu night especially over IA. LONG TERM...Saturday through Tuesday night Central IL gets into a WNW upper level flow during the weekend into early next week with disturbances tracking ESE over top of ridge across the Midwest and interacting with a humid air mass to trigger daily chances of showers and thunderstorms. An upper level trof digging into the Midwest Monday afternoon and Monday night to drive a cold front SE into IL Monday night and increase chances of showers and thunderstorms then with gradually cooler air by Tue. 07 && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
638 AM CDT WED JUN 18 2014 .DISCUSSION... 543 AM CDT COMPLEX OF SHOWERS AND THUNDERSTORMS CONTINUES TO MOVE EAST- SOUTHEAST ACROSS NORTH CENTRAL AND NORTHEAST IOWA. INTENSITY HAS WANED SOMEWHAT THOUGH THERE HAS BEEN SOME NEW DEVELOPMENT AT TIMES. COLD POOL STILL SEEMS TO BE MAINTAINING ITSELF WITH OUTFLOW TURNING WINDS NORTHWESTERLY THEN EASTERLY WINDS FILLING IN BEHIND. STILL SOME QUESTION ON HOW LONG THIS WILL BE MAINTAINED BUT TRAJECTORY HAS BEEN STEADY AND TAKES THE SOUTHERN PORTION OF THE COMPLEX ACROSS THE NORTHERN TIER OR TWO OF COUNTIES BASED ON ITS CURRENT FORM...OR PRIMARILY ALONG AND NORTH OF I-88/I-290. THE COMPLEX HAS SPED UP A BUT AND ARRIVAL IN THE FAR NORTHWEST CORNER OF THE AREA LOOKS TO BE DURING THE 13Z HOUR. SOME GUSTINESS LOOKS TO ACCOMPANY THE ARRIVAL IN THE NORTHWEST BUT THE PRIMARY CONCERN WILL BE HEAVY DOWNPOURS. HAVE ADDED SOME DETAIL TO POPS THROUGH THE MORNING. EXPECT THAT AN OUTFLOW BOUNDARY WILL BE LEFT BEHIND WHEN THE COMPLEX EXITS OR DECAYS WHICH COULD END UP BEING THE FOCUS FOR NEW DEVELOPMENT LATER TODAY. WILL LEAVE TEMPS AS-IS FOR THE REST OF THE DAY BUT THEY MAY BE AFFECTED DEPENDING ON THE ABILITY TO DESTABILIZE THIS AFTERNOON. MDB //PREV DISCUSSION... 307 AM CDT CONVECTIVE CHANCES REMAIN THE FOCUS THROUGH THE FORECAST PERIOD AS THE LARGE SCALE UPPER TROUGH PARKED OVER THE WESTERN U.S. SLOWLY EVOLVES THROUGH THE WEEKEND. EARLY MORNING WATER VAPOR IMAGERY SHOWS THIS LARGE UPPER LOW SPINNING OVER IDAHO WITH RIDGING JUST TO ITS EAST ACROSS THE MID MISSISSIPPI RIVER VALLEY INTO CENTRAL CANADA. NUMEROUS WAVES CONTINUE TO TRAVERSE THE LOWER AMPLITUDE PORTION OF THE RIDGE ACROSS THE PLAINS/MID AND UPPER MISSISSIPPI RIVER VALLEY SERVING TO FOCUS AREAS OF CONVECTION. ALSO OF NOTE IS A TROUGH THAT IS MOVING SOUTHWARD ACROSS ONTARIO AND QUEBEC. AT THE SURFACE...LOW PRESSURE IS IS PARKED OVER EASTERN COLORADO WITH A WARM FRONTAL BOUNDARY STRETCHING EASTWARD ACROSS SOUTHERN MINNESOTA AND CENTRAL WISCONSIN. IT THEN ARCS DOWN LAKE MICHIGAN AND EASTWARD TO ANOTHER SURFACE LOW OVER NORTHERN NEW YORK. TODAY AND TONIGHT...ANOTHER TOUGH FORECAST FOR TODAY WITH ONGOING CONVECTION AFFECTING HOW THINGS EVOLVE THROUGH THE DAY/EVENING. WARM FRONTAL BOUNDARY HAS LIFTED NORTH OF THE CWA EARLY THIS MORNING WITH MAIN CORRIDOR OF CONVECTION ALONG AND NORTH OF THE FRONT. THUNDERSTORM COMPLEX OVER NORTH CENTRAL IOWA HAS BECOME BETTER ORGANIZED AND HAS ACCELERATED EASTWARD. THE LOW LEVEL JET IS FOCUSED INTO NORTH CENTRAL IOWA BUT MOIST LOW/MID LEVEL FLOW TURNS MORE SOUTHWESTERLY TO THE EAST. 850-300 MB THICKNESS FIELDS DO SHOW A SOUTHEASTERLY COMPONENT WITH THE INSTABILITY GRADIENT ALSO ORIENTED A BIT NW-SE. PROGRESSION OF THIS COMPLEX WILL NEED TO BE WATCHED THE NEXT FEW HOURS AS A TURN TO THE SOUTHEAST IS SUGGESTED BY THE ABOVE ALONG WITH A TURNING OF FORWARD PROPAGATING CORFIDI VECTORS AFTER DAYBREAK. SHOULD THIS COMPLEX MAINTAIN ITSELF AND TURN MORE SOUTHEASTERLY THEN AT LEAST NORTHERN AREAS OF THE CWA WILL BE AFFECTED DURING THE MID/LATE MORNING HOURS. WOULD EXPECT THAT THE COMPLEX WOULD BE IN A DECAYING STATE AT THAT TIME BUT A STRONG COLD POOL SEEMS TO BE DEVELOPING AND UNSTABLE AIR WILL BE IN PLACE LOCALLY SO MAINTENANCE IS POSSIBLE. WILL GO AHEAD AND INDICATE HIGHER CHANCE POPS FOR THE NORTHERN THIRD TO HALF OF THE AREA LATE MORNING INTO MIDDAY BUT THESE WILL NEED TO BE TWEAKED BASED ON EVOLUTION OF THE COMPLEX THROUGH DAYBREAK. LOOKING TOWARDS THE AFTERNOON...WITH CONVECTION AFFECTING MUCH OF THE NEAR TERM GUIDANCE WILL CONTINUE TO APPROACH THE FORECAST FROM A LARGER SCALE PERSPECTIVE. THE UPPER TROUGH MOVING SOUTHWARD ACROSS CENTRAL ONTARIO LOOKS TO BECOME A KEY PLAYER IN OUR CONVECTIVE CHANCES LATER TODAY AND TONIGHT AS IT WILL BE DROPPING ACROSS THE LOWER GREAT LAKES WITH A STRONG SURFACE HIGH SPREADING SOUTHWARD AS WELL. THIS WILL PUSH THE STATIONARY BOUNDARY SOUTHWARD TO THE EAST WHILE THE UPPER TROUGH TO THE WEST PROGRESSES NORTHEAST ACROSS MONTANA PUSHING SOMEWHAT DISORGANIZED SURFACE LOW PRESSURE NORTHWARD. THIS WILL CAUSE THE BOUNDARY TO BECOME ORIENTED FROM NW TO SE INTO THE EVENING. THE SHIFTING OF THESE TROUGHS WILL ALLOW FOR THE UPPER RIDGE TO SHARPEN OVER THE MID-UPPER MISSISSIPPI RIVER VALLEY BUT IT IS WEAKER CLOSER TO THE LOCAL AREA SO SHORTWAVES MAY CONTINUE TO EMANATE THROUGH IT. WITH THE FRONTAL ZONE RE-ORIENTING THE LOCAL AREA LOOKS TO BE MORE SQUARELY PLACED WITHIN IT SUGGESTING THAT OUR CONVECTIVE CHANCES WILL INCREASE. MORNING CONVECTION WILL LIKELY DETERMINE HOW THINGS PLAY OUT THIS AFTERNOON AND PROBABLY LOWER EARLY AFTERNOON CHANCES ASSUMING THINGS STABILIZE FROM OUTFLOW OF THE COMPLEX TO THE NORTH OF IN THE WAKE OF CONVECTION CROSSING THE CWA...BUT THIS REMAINS TO BE SEEN. SEE BETTER LARGER SCALE POTENTIAL THIS EVENING AND OVERNIGHT AS THE FRONT SHIFTS SO WILL CARRY HIGHEST POPS DURING THAT TIME. IF CONVECTION STAYS NORTH THEN THERE SHOULD BE NO PROBLEM HAVING HIGH TEMPS REACH THE UPPER 80S AND LOWER 90S THIS AFTERNOON. MORNING/MIDDAY CONVECTION WOULD LIKELY RESULT IN LOWER TEMPS...THOUGH A LATE DAY RALLY IS POSSIBLE. LAKE BREEZE PROCESSES MAY COMBINE WITH THE SHIFTING FRONT TO BRING NORTHEAST WINDS TO LAKESHORE AREAS LATE THIS AFTERNOON BUT THIS MAY BE AFFECTED BY MORNING CONVECTION AS WELL. WILL HAVE EARLY HIGHS ALONG THE LAKE WITH A COOLING TREND DURING THE AFTERNOON. THURSDAY AND FRIDAY...THE UPPER LOW WILL MEANDER NORTH AND EAST INTO SOUTHERN ALBERTA WHILE THE UPPER TROUGH THAT IS OVER ONTARIO THIS MORNING CONTINUES SOUTHWARD INTO NEW ENGLAND. SURFACE HIGH PRESSURE WILL BE SETTLING INTO EASTERN ONTARIO AND WESTERN QUEBEC. POTENTIAL ONGOING CONVECTION WILL BE A DRIVER OF THINGS BUT SYNOPTICALLY SPEAKING THE WARM FRONT SHOULD BE ORIENTED MORE NORTHWEST TO SOUTHEAST. CONVECTIVE CHANCES WILL CONTINUE WITH THE BOUNDARY LIKELY TO BE IN THE AREA AS WELL AS A LIKELIHOOD OF WEAK UPPER IMPULSES TO MOVE THROUGH THE RIDGED FLOW OVERHEAD. WARM AND HUMID CONDITIONS WILL PERSIST SO ASSUMING CONVECTION IS NOT LIMITING TEMPS...UPPER 80S ARE EXPECTED...THOUGH A SOUTHEASTERLY WIND WILL COOL THE ILLINOIS LAKESHORE AREAS. BY FRIDAY...THE UPPER LOW WILL START TO MOVE TO THE EAST WITH A COOL FRONTAL BOUNDARY NOW STRETCHING SOUTHWARD FROM THE ASSOCIATED SURFACE LOW OVER THE FAR NORTHERN PLAINS/SOUTHERN CANADIAN PRAIRIES. THIS FRONT WILL PUSH EAST ACROSS THE AREA FRIDAY PERHAPS BRINGING A BETTER FOCUS FOR STORMS...THOUGH IT MAY CROSS EARLY IN THE DAY LIMITING THE POTENTIAL FOR NEW DEVELOPMENT. NOT EXPECTING MUCH CHANGE IN TEMPS/HUMIDITY BEHIND THE FRONT SO MID AND UPPER 80S WILL PROBABLY CONTINUE. SATURDAY AND BEYOND...THE UPPER LOW WILL DE-AMPLIFY OVER SOUTHERN MANITOBA INTO SATURDAY. THIS WILL LEAD TO A MORE ZONAL FLOW ACROSS MUCH OF THE CONUS. THIS WILL BE SUPPORTIVE OF WEAK SHORTWAVES MOVING THROUGH THE FLOW WHICH WILL LEAD TO MORE CHANCES FOR CONVECTION SATURDAY AND SUNDAY. ANOTHER UPPER TROUGH WILL MOVE SOUTHWARD INTO EASTERN CANADA LATER SUNDAY WHICH GUIDANCE CONTINUES TO PHASE WITH THE WEAKENED UPPER TROUGH ACROSS SOUTHERN CANADA. THE DEGREE OF PHASING CONTINUES TO VARY AMONG RUNS WHICH IS NOT SURPRISING GIVEN THE TIME RANGE AND WHAT NEEDS TO OCCUR PRIOR TO THAT TIME. WITH THIS TROUGH PASSING OVER OR TO THE NORTHEAST OF THE AREA MID LEVEL TEMPS WILL COOL EARLY NEXT WEEK...WITH COOLER AIR AND REDUCED HUMIDITY THANKS TO A NORTHEASTERLY LOW LEVEL FLOW. MDB && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 12Z... * PERIODIC CHANCES FOR THUNDERSTORMS DURING THE TAF PERIOD. * SSW WINDS TODAY TURNING TO THE NORTHEAST THIS AFTERNOON/EVENING. BMD //DISCUSSION...UPDATED 12Z... ANOTHER DAY OF PRIMARILY VFR CONDITIONS ON TAP WITH A GREAT DEAL OF UNCERTAINTY SURROUNDING THUNDERSTORMS CHANCES. THIS MORNING...A FRONTAL BOUNDARY IS DRAPED NEAR THE IL/WI STATE LINES WITH OVERNIGHT CONVECTION OCCURRING NORTH OF THE FRONT. FARTHER WEST...AN AREA OF MORE ROBUST THUNDERSTORMS IS PUSHING EAST ACROSS NORTHERN IOWA THOUGH HAS SHOWN SOME SIGNS OF WEAKENING AND EXPECT THIS TREND TO CONTINUE THROUGH THE MORNING. THUNDERSTORMS ARE CURRENTLY NOT EXPECTED TO MAKE IT INTO RFD BUT REMNANT SHOWERS MAY PERSIST PUSHING THROUGH STARTING IN THE 14-15Z HOUR. MODERATE TO STRONG INSTABILITY IS ONCE AGAIN PROGGED TO DEVELOP ACROSS THE REGION TODAY AND WILL BE CAPPED EARLY IN THE DAY THOUGH THE CAP STARTS TO ERODE MID AFTERNOON. THERE IS LITTLE IN THE WAY OF UPPER LEVEL SUPPORT WITH EVEN WEAK MID LEVEL HEIGHT RISES BUILDING OVER THE AREA THIS AFTERNOON THAT MIGHT HELP SUPPRESS NEW GROWTH. CHANCES FOR THUNDERSTORM DEVELOPMENT THIS AFTERNOON ARE NOT ZERO BUT LOW ENOUGH TO PRECLUDE ANY REFERENCE IN THE TAFS. THE BEST CHANCES APPEAR TO BE LATE AFTERNOON INTO THE EVENING AS THE FRONT SAGS SOUTH INTO THE AREA...THOUGH MAY COME THROUGH QUICKER IN FAR NORTHEAST ILLINOIS AS AN ENHANCED LAKE BREEZE. WITH THE CAP FAIRLY WEAK AT THIS POINT...THIS MAY SERVE THE FOCUS FOR MORE WIDESPREAD THUNDERSTORM DEVELOPMENT. WINDS SHOULD GRADUALLY VEER BACK AROUND TO THE SOUTHEAST LATE TONIGHT INTO EARLY THURSDAY AS THE WARM FRONT LIFTS BACK TO THE NORTH. BMD //ORD AND MDW CONFIDENCE...UPDATED 12Z... * LOW CONFIDENCE IN TSRA THIS MORNING OR AFTERNOON...LOW-MEDIUM CONFIDENCE THIS EVENING/TONIGHT. * MEDIUM CONFIDENCE IN WIND SHIFT TO NE AND TIMING WITHIN AN HOUR OR TWO. * HIGH CONFIDENCE IN PREVAILING VFR CONDITIONS OUTSIDE INFLUENCE OF TSRA. BMD //OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z... THURSDAY NIGHT THROUGH TUESDAY...PRIMARILY VFR WITH PERIODIC CHANCES FOR THUNDERSTORMS. BMD && .MARINE... 247 AM CDT A FRONTAL BOUNDARY WILL LINGER IN THE VICINITY OF LAKE MICHIGAN THROUGH THE REMAINDER OF THE WEEK. IN GENERAL...SOUTH WINDS ARE EXPECTED SOUTH OF THE BOUNDARY WITH NORTHEAST WINDS NORTH OF THE BOUNDARY. THE FRONT IS EXPECTED TO SAG SOUTH ACROSS LAKE MICHIGAN TODAY...THEN LIFT BACK NORTH AGAIN THURSDAY INTO FRIDAY. HIGH PRESSURE WILL BUILD JUST EAST OF LAKE MICHIGAN LATE IN THE WEEK INTO THE WEEKEND AND SHOULD RESULT IN RELATIVELY MODEST WINDS ACROSS THE LAKE THIS WEEKEND INTO EARLY NEXT WEEK. BMD && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion National Weather Service Lincoln IL 638 AM CDT Wed Jun 18 2014 .DISCUSSION... ISSUED 330 AM CDT Wed Jun 18 2014 SHORT TERM...Today through Friday night Will issue another special weather statement to address the heat and humidity today and Thursday with highs around 90F and heat indices peaking from 95 to 100F similar to what we experienced yesterday. Strong upper level ridge (592 dm 500 mb high pressure over the southeast states) has been keeping much of central and southeast IL dry with the heat and humidity. MCS`s bringing more strong to severe thunderstorms with heavy rains north of IL over MN/WI and northern IA early this morning. These MCS`s forming on nose of low level jet interacting with frontal boundary draped over southern Great Lakes and upper MS river valley and extends to 999 mb low pressure in NE CO. Strong 558 dm 500 mb low was along the ID/MT border with series of MCS east of it from SD into the southern Great Lakes. Upper level low near ID/MT border to lift NE into southern Saskatchewan by sunset Thu while short waves to weaken top of upper level ridge and increase chances of convection over central IL from north to south from this afternoon through next few days as frontal boundary sags back south toward central IL by Friday. Most areas will still be dry this morning with isolated convection developing in the tropical air mass this afternoon especially northern areas. RAP and HRRR models also show some qpf in far SE IL from Lawrenceville SE this afternoon. SPC has shifted slight risk of severe storms further south tonight to included most of central IL with just southern six counties not in slight risk. Highest risk of severe storms still appears north of Peoria where 30% risk of large hail and damaging wind gusts where best bulk shear in combination with moderate to strong instability. Highest convection chances of 50-60% over northern counties from tonight through Thu night shift further south during Friday with frontal boundary. SPC keeps slight risk NW of CWA Thu afternoon & Thu night especially over IA. LONG TERM...Saturday through Tuesday night Central IL gets into a WNW upper level flow during the weekend into early next week with disturbances tracking ESE over top of ridge across the Midwest and interacting with a humid air mass to trigger daily chances of showers and thunderstorms. An upper level trof digging into the Midwest Monday afternoon and Monday night to drive a cold front SE into IL Monday night and increase chances of showers and thunderstorms then with gradually cooler air by Tue. 07 && .AVIATION... ISSUED 637 AM CDT Wed Jun 18 2014 A very challenging forecast, as convection will be dictated by various residual outflow boundaries plus a surface front across northern Illinois that may drift south a bit tonight. With the various synoptic and high-resolution models showing a wide variety of solutions, confidence on thunder elements of the TAF set is lower than usual. Have generally gone with VCTS mentions with a PROB30 group this evening to try and highlight a more likely time frame of any temporary MVFR conditions, based on the output of the ARW and NMM models. Kept KSPI/KDEC dry into early evening, but isolated showers/storms may occur earlier as well. Geelhart && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
1011 AM EDT WED JUN 18 2014 .SYNOPSIS... ISSUED AT 422 AM EDT WED JUN 18 2014 PERIODS OF SHOWERS AND THUNDERSTORMS WILL REMAIN POSSIBLE THROUGH THE NEXT SEVERAL DAYS AS A WEAK FRONTAL BOUNDARY SETS UP OVER THE SOUTHERN GREAT LAKES. THUNDERSTORMS ARE BEING AIDED BY VERY WARM AND HUMID AIRMASS CURRENTLY IN PLACE ACROSS THE REGION. HIGHS TODAY WILL BE IN THE UPPER 80S TO LOWER 90S WITH OVERNIGHT LOWS AROUND 70. && .UPDATE... ISSUED AT 1010 AM EDT WED JUN 18 2014 INTERESTING BUT COMPLICATED NR TERM THIS MORNING AS POTENT UPSTREAM MCV PIVOTS OUT OF SE MN. ATTENDANT BKN LINE OF CONVN FM SRN WI SWWD INTO ERN SHOWING SIGNS NOW OF FWD PROPAGATION INTO RAPIDLY GROWING INSTABILITY AXIS POSITIONED W-E ACRS THE SRN LAKES INVOF DECAYING CIRRUS SHIELD...AND NO DOUBT AUGMENTED W/POTENT 50KT MID LVL SPEED MAX. HWVR COMPLICATING FCTR IS OUTFLW BNDRY EXTENDING FM FAR NE IL ESE INTO NW OH THAT MAY WITH TIME INITIATE ADDNL CONVN AHD OF THE BOWING LINE MVG OUT OF SE WI. AT EITHER RATE IT WOULD APPEAR A MORE CONSIDERABLE RISK FOR SEVERE STORMS IS SHAPING UP FOR THIS AFTN. ZONE UPDATES WILL BE FORTHCOMING. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 422 AM EDT WED JUN 18 2014 ACTIVE WEATHER PATTERN CONTINUES FOR THE SOUTHERN GREAT LAKES AS SEVERAL CONVECTIVELY ENHANCED SHORTWAVES EJECT OUT OF WESTERN CONUS UPPER LOW AND TRAVEL ALONG QUASI-STATIONARY E-W FRONTAL BOUNDARY DRAPED THROUGH THE REGION. STRONG LLJ AHEAD OF THE MAIN TROUGH IS STILL MAINTAINING A CONTINUAL FEED OF VERY HIGH THETA-E AIR INTO THE MIDWEST AND OHIO VALLEY...SUPPORTING UNSTABLE CONDITIONS. SIMILAR TO THE PREVIOUS NIGHT...CONVECTION HAS FIRED UPSTREAM ON THE NOSE OF THE LLJ/MOISTURE CONVERGENCE AND HAS SLOWLY DRIFTED EASTWARD. THE DIFFERENCE IS THAT STORM CLUSTERS HAVE BEEN A LITTLE MORE DISCREET AND DISORGANIZED THUS FAR. UPSCALE GROWTH/ORGANIZATION LIKELY INHIBITED BY VERY STRONG CAPPING INVERSION NOTED ON 00Z KILX AND KDVN SOUNDINGS AS WELL AS A LACK OF ANY CLEAR SYNOPTIC SCALE SHORTWAVE/LINEAR FORCING. STORM CLUSTERS TO OUR NORTH AND NORTHWEST HAVE GRADUALLY FILLED IN/CONGLOMERATED DURING THE PAST FEW HOURS THOUGH...THANKS TO NOCTURNAL STRENGTHENING OF LLJ AND ASSOCIATED INCREASE IN LOW LEVEL MOISTURE AVAILABLE UPSTREAM. QUESTION IS HOW WILL THIS ACTIVITY EVOLVE THROUGH THE MORNING AND INTO THE AFTERNOON. LATEST SURFACE OBS ACTUALLY SHOW A FAIRLY PRONOUNCED TEMP AND MOISTURE GRADIENT JUST NORTH OF OUR CWA. ISENTROPIC ASCENT ALONG AND NORTH OF THIS SURFACE BOUNDARY IS DRIVING MUCH OF THE CURRENT CONVECTION WHILE ATMOSPHERE REMAINS CAPPED TO THE SOUTH. NOTHING TO FORCE THIS FRONT SOUTHWARD THROUGH THE MORNING WITH CONTINUAL SOUTHWEST FLOW/WAA AND NO ORGANIZED COLD POOLS/OUTFLOW BOUNDARIES AS OF YET. THEREFORE EXPECT OUR CWA WILL REMAIN LARGELY DRY DURING THIS PERIOD. SITUATION MAY CHANGE BY THE AFTERNOON AND EVENING. 00Z MODELS SUGGEST THAT A SUBTLE WAVE ASSOCIATED WITH CONVECTION CURRENTLY OVER FAR NW IA AND SOUTHERN MN WILL PUSH ESE BY LATER TODAY. SIMULTANEOUS SOUTHWARD PUSH OF CANADIAN ANTICYCLONE MAY FORCE THE FRONTAL BOUNDARY SOUTHWARD A BIT...WITH THE HELP OF COLD LAKES AND OUTFLOW FROM MORNING THUNDERSTORMS. MODELS INDICATE THIS WILL LIKELY BE ENOUGH TO WEAKEN THE STRONG CAP IN PLACE ACROSS OUR CWA AND ALLOW STORMS TO DEVELOP AND/OR PROPAGATE INTO OUR AREA BY THE AFTERNOON AND EVENING. LATEST HRRR AND HI-RES WRF-NMM ARE GENERALLY IN LINE WITH THIS IDEA. IF THE CAP DOES BREAK AS EXPECTED THEN SEVERE WEATHER WILL BE QUITE POSSIBLE. MODIFIED FORECAST SOUNDINGS INDICATE AROUND 3000 J/KG OF SBCAPE ACROSS THE AREA BY THE AFTERNOON. 0-6KM BULK SHEAR IS NOT AS HIGH SOUTH OF I-80 BUT SUFFICIENT FOR ORGANIZED LINE SEGMENTS/BOWS GIVEN LARGELY UNIDIRECTIONAL WIND FIELDS. LARGE HAIL AND STRONG WINDS WOULD BE THE PRIMARY THREATS WITH ANY STORMS THAT DO DEVELOP. THREAT FOR TORNADOES IS MUCH LOWER GIVEN LIMITED LOW LEVEL DIRECTIONAL SHEAR BUT CAN`T RULE IT OUT ENTIRELY. ALL OF THIS IS OF COURSE CONDITIONAL ON MORNING CONVECTIVE TRENDS AND GETTING ENOUGH SYNOPTIC SCALE ASCENT/COOLING TO ERODE THE STOUT 850-750MB INVERSION. CONFIDENCE IN THIS SCENARIO IS NOT HIGH ENOUGH TO SUPPORT LIKELY POPS JUST YET AND WILL HOLD WITH HIGH END CHANCES. THESE CHANCES WILL CONTINUE INTO THE OVERNIGHT PERIOD AS LLJ STRENGTHENS ONCE AGAIN AND POSSIBLY SUPPORTS PERSISTENT CONVECTION FOR OUR CWA IF SOUTHWARD PUSH OF FRONTAL BOUNDARY MATERIALIZES. && .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 422 AM EDT WED JUN 18 2014 LITTLE SUBSTANTIVE CHANGE TO LONG TERM PERIOD. EXPECT PRODIGIOUS CONVECTION SPAWNING ALONG/DOWNSTREAM OF INTENSE INTERMOUNTAIN MID TROPOSPHERIC VORTEX TO CONTINUE INTO THIS WEEKEND. ACTIVE PATTERN WITH CONTINUATION OF CONVECTIVE INDUCED MESOVORTICIES AFFORDING TO INITIATE/RENEW TSRA ALONG/NORTH OF SURFACE FRONTAL BOUNDARY THAT PRESENTLY EXTENDS FROM NORTHERN NE TO CENTRAL WI THEN SOUTHEASTWARD THROUGH THE SOUTHERN GREAT LAKES REGION. WHILE STRONGEST INSTABILITY AND MORE SIGNIFICANT FOCUS FOR INITIATION REMAINS UPSTREAM OF CWA ON THU...HAVE CONTD CHC POP MENTION/HIGHEST IN SOUTHWEST CWA AS NORTHERN ONTARIO ANTICYCLONE SHIFTS SEWD AND ASSERTS RIDGING SOUTHWARD THROUGH LAKE HURON INTO NWRN OH...SHUNTING CONVECTIVE MAINTENANCE FARTHER SOUTH AS IT PROGRESSES DOWNSTREAM. FRIDAY PRESENTS EVEN HIGHER POTENTIAL FOR MORE WIDESPREAD CONVECTION AS LOBE OF SIGNIFICANT 30-50M/12 HR MID LEVEL HEIGHT FALLS PEELS THROUGH WESTERN GREAT LAKES AS PRIMARY UPSTREAM VORTEX BIFURCATES DOWNSTREAM RIDGE TO BECOME REXED ACROSS SOUTHERN MANITOBA. MID 80S/NEAR 70 SURFACE CONDITIONS YIELD MODERATE INSTABILITY 2500-3500 J/KG SBCAPE AND MODEST DEEP LAYER SHEAR. DIFFERENTIATED FRIDAY WITH LIKELY POPS SANS TIMING GIVEN BETTER SIGNALS AMID RICH THETA-E REGIME FIRMLY IN PLACE. THEREAFTER INCREASING MODEL DIVERGENCE NOTED WITH DEVOLUTION OF REXED SYSTEM WITH ECMWF/GEM MAINTAINING ORPHANED TROFFING ACROSS NORTHERN GREAT LAKES INTO NORTHERN PLAINS INTO NEXT WEEK AND GFS ESPECIALLY BTWN ECMWF AND GEM VS GFS RELEASE DOWNSTREAM THROUGH THE LOWER GREAT LAKES DYS5/6. POSSIBLE LULL SATURDAY THOUGH HIGHLY CONTINGENT ON FRIDAY CONVECTION LEADING TO SUBSTANTIAL OVERTURNING AND FAR SOUTHWARD BOUNDARY SHUNT. AT THIS TIME LOW CHANCE MENTION REMAINS GIVEN HIGH CONDITIONALITY. TREND DRY MONDAY NIGHT/TUESDAY AS DEEPER NORTH/NORTHEAST FLOW PER NORTHERN GREAT && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING) ISSUED AT 558 AM EDT WED JUN 18 2014 WIDESPREAD THUNDERSTORMS HAVE DEVELOPED ALONG AND NORTH OF A WARM FRONT CURRENTLY STRETCHED FROM SOUTHERN MICHIGAN THROUGH NORTHERN IOWA WITH DRY AND CAPPED CONDITIONS SOUTH OF THAT FRONT IN OUR AREA. FRONT EXPECTED TO RETREAT SOUTHWARD LATER TODAY THOUGH AS SHORTWAVE TROUGH PASSES THROUGH THE REGION. THIS WILL LIKELY WEAKEN THE CAP AND ALLOW THUNDERSTORMS TO DEVELOP AND/OR PROPAGATE INTO NORTHERN INDIANA. SEVERAL HI-RES MODELS SUPPORT THIS SCENARIO BUT DISAGREE ON EXACT TIMING. FOR NOW THINK THE BEST CHANCE WILL BE AFTER 16Z AT KSBN AND AFTER 18Z AT KFWA. SCATTERED CONVECTION WILL LIKELY LINGER THROUGH THE OVERNIGHT PERIOD AS LLJ RAMPS UP ONCE AGAIN. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ UPDATE...T SYNOPSIS...AGD SHORT TERM...AGD LONG TERM...MURPHY AVIATION...AGD VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.NORTHERNIN.GOV WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1035 AM EDT WED JUN 18 2014 .UPDATE... ISSUED AT 1035 AM EDT WED JUN 18 2014 14Z SFC ANALYSIS SHOWS HIGH PRESSURE OFF TO THE SOUTHEAST OF KENTUCKY WITH A PERSISTENT AND BROAD AREA OF LOW PRESSURE OVER THE PLAINS. FROM THIS LOW...A QUASI-STATIONARY BOUNDARY EXISTS ACROSS THE SOUTHERN TIER OF THE GREAT LAKES SERVING AS A GUIDE PATH FOR PERIODIC CLUSTERS OF SEMI-ORGANIZED STORMS. THAT SHOULD BE THE CASE TODAY...AS WELL. CLOSER TO HOME...THE HIGH PRESSURE SOUTH OF THE FRONT IS FAIRLY WEAK...ALONG WITH THE RIDGE ALOFT. THIS HAS HAD PROBLEMS KEEPING THE AREA BLEMISH FREE THROUGH PEAK HEATING THE PAST COUPLE OF DAYS AND TODAY SHOULD BE NO DIFFERENT. IN FACT...DUE TO THE CONTINUED FLOW OF WARM...MOIST...AND UNSTABLE AIR INTO THIS PART OF THE STATE DO EXPECT TO SEE A LITTLE BIT MORE COVERAGE OF ANY ACTIVITY LATE THIS AFTERNOON. THE HRRR SUPPORTS THIS...ALBEIT A BIT GUNG-HO WHEN COMPARED TO PERSISTENCE AND THE NAM12...AND AS OTHER COARSER RESOLUTION MODELS. NEVERTHELESS...THE CONDITIONS APPEAR TO WARRANT THE INTRODUCTION OF ISOLATED POPS FOR THE LATTER PART OF THE AFTERNOON. HAVE ADDED THESE TO THE GRIDS AND UPDATED THE ZONES/HWO TO CONVEY THE CONCERN. ALSO FINE TUNED TEMPERATURES...DEWPOINTS...AND SKY COVER THROUGH THE NEXT SEVERAL HOURS PER THE LATEST OBS... TRENDS...AND GUIDANCE. THESE HAVE BEEN SENT TO THE NDFD AND WEB SERVERS. && .SHORT TERM...(TODAY THROUGH THURSDAY) ISSUED AT 229 AM EDT WED JUN 18 2014 ANOTHER HOT AND HUMID DAY IS IN STORE FOR EASTERN KENTUCKY. THE HIGH PRESSURE REMAINS FIRMLY IN CONTROL. THE QUASI-STATIONARY FRONT DRAPED ACROSS THE GREAT LAKES WILL BEGIN TO MOVE A LITTLE TO THE SOUTH. THIS WILL MOVE THE CONVECTION TO THE SOUTH AS WELL. THE BIG QUESTION IS THE TIMING OF THIS FRONT AND WHEN THE PRECIPITATION WILL FINALLY BE ABLE TO MOVE INTO EASTERN KENTUCKY. THE MODELS HAVE CONSISTENTLY BEEN TOO QUICK TO BREAK DOWN THE RIDGING AND ALLOW THE SYSTEM TO MOVE SOUTH. THIS BEING SAID...THE LEADING EDGE MAY BE MOVING INTO THE NORTHERN PORTION OF THE AREA TONIGHT WITH SOME ISOLATED TO SCATTERED THUNDERSTORMS AND THEN ACROSS ALL OF EASTERN KENTUCKY ON THURSDAY. STILL HAVE SOME CONCERN THAT ANY THUNDERSTORMS THAT DEVELOP COULD BE STRONG DUE TO THE INSTABILITY AND THE POTENTIAL ENERGY CREATED BY A COMBINATION OF THE INSTABILITY AND MOISTURE. THE LIFTED INDEX THIS EVENING IS FORECAST TO BE AROUND -6 WITH 3000 TO 4000 JOULES OF CONVECTIVE AVAILABLE POTENTIAL ENERGY (CAPE). TONIGHT...THERE WILL BE A WEAK SHORT WAVE MOVING ACROSS THE AREA. THIS MAY PROVIDE THE NECESSARY TRIGGER TO GET THE CONVECTION GOING. ON THURSDAY...THE MODELS ARE SHOWING A LOT MORE MOISTURE ALOFT MOVING INTO THE AREA WITH PRECIPITABLE WATER VALUES AROUND 1.6 INCHES. THIS COULD ALLOW FOR SOME SOAKERS...ESPECIALLY FOR ANY CELLS THAT TRAIN. THE O-6 KM WINDS ARE ONLY FORECAST TO BE AROUND 11 MPH. WITH THE SLOW MOVING CELLS...THE STORMS WILL BE ABLE TO DUMP MORE WATER AND THIS COULD CAUSE SOME OF THE DITCHES AND LOW WATER CROSSING TO BE RUNNING FULL. EXPECT ANOTHER UNCOMFORTABLE DAY WITH NEAR RECORD TEMPERATURES. THE REPEATED HOT DAYS AND FAIRLY WARM EVENINGS...COULD START TO STRESS THE ELDERLY AND THE INFIRM AS WELL AS LIVESTOCK AND PETS. SOME EXTRA CARE SHOULD BE TAKEN TO PROVIDE ADEQUATE HYDRATION AND COOLING. .LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY) ISSUED AT 302 AM EDT WED JUN 18 2014 MORE OF THE SAME IN THE EXTENDED THIS GO ROUND. THE MODELS ARE STILL HAVING A VERY DIFFICULT TIME CONVERGING ON A COMMON SOLUTION AS FAR AS THE OVERALL LARGE SCALE WEATHER PATTERN AND THE TIMING OF WEATHER SYSTEM PASSAGE ACROSS THE CONUS FROM THURSDAY NIGHT ONWARD. WITH THAT BEING SAID...WENT WITH A SLIGHTLY MODIFIED VERSION OF THE STANDARD LONG TERM GRID POPULATION PROCEDURE...WITH THE DATA BEING BLENDED WITH WHAT I FELT WAS THE MORE REASONABLE GFS MODEL GUIDANCE. THERE WILL BE A CHANCE OF SHOWERS EACH DAY IN THE EXTENDED...WITH THE HIGHER RAIN CHANCES GENERALLY OCCURRING DURING THE AFTERNOON AND EVENING HOURS DURING PEAK HEATING. THIRTY TO FIFTY PERCENT PRECIPITATION PROBABILITIES WERE USED ACROSS THE BOARD TO REFLECT THIS. A COUPLE OF FRONTAL BOUNDARIES...AND FRONTAL WAVES MOVING ALONG THEM...WILL BE THE TRIGGERING MECHANISMS FOR SHOWERS AND STORMS. THE EXTENDED PERIOD WILL STILL BE QUITE WARM...WITH ABOVE NORMAL TEMPERATURES...BUT NOT NEARLY AS WARM AS IT HAS BEEN THE PAST COUPLE OF DAYS ACROSS EASTERN KENTUCKY. LOOK FOR HIGHS MOSTLY IN THE MID 80S...WITH SLIGHTLY COOLER VALUES TOWARD THE END OF THE PERIOD AS SHOWERS AND STORMS BECOME MORE WIDESPREAD AS A FRONTAL BOUNDARY MEANDERS ABOUT THE REGION. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING) ISSUED AT 749 AM EDT WED JUN 18 2014 THE PATCHY VALLEY FOG WILL BURN OFF BY 13Z AND THEN FORM AGAIN NEAR DAWN TOMORROW. THE MIST MAY MAKE IT UP TO THE TAF STATIONS AROUND 11Z. SOME ISOLATED CONVECTION IS POSSIBLE TONIGHT...HOWEVER THE EXTENT AND TIMING IS TOO UNSURE TO PUT ANYTHING INTO THE TAF AT THIS TIME. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GREIF SHORT TERM...JJ LONG TERM...AR AVIATION...JJ
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
1044 AM EDT WED JUN 18 2014 .SYNOPSIS... A RIDGE OF HIGH PRESSURE WILL REMAIN ACROSS THE WESTERN ATLANTIC AND SOUTHEAST STATES THROUGH TONIGHT. A WEAK COLD FRONT WILL MOVE INTO THE REGION FROM THE NORTHWEST ON THURSDAY AND WILL STALL OVER THE SOUTHERN MID-ATLANTIC FRIDAY INTO THE WEEKEND. ANOTHER WEAK COLD FRONT APPROACHES EARLY NEXT WEEK...CONTINUING AN ACTIVE PATTERN. && .NEAR TERM /THROUGH THURSDAY/... PATTERN THIS MORNING REMAINS A TROUGH OVER NEW ENGLAND...CLOSED LOW OVER THE NRN ROCKIES..AND AN HIGH CENTERED OVER FL WITH A PLUME OF GULF MOISTURE INTO THE UPPER MIDWEST. ONGOING MCS NEAR MILWAUKEE WILL NEED TO BE MONITORED. RECENT HRRR RUNS HAVE SENT THIS ACTIVITY INTO THE NRN MID-ATLANTIC...WHICH MAKES SENSE GIVEN THE POSITION OF THE SFC HIGH OVER GA WITH MAINLY ZONAL FLOW OVER THE ERN CONUS. ONGOING ACTIVITY OVER WRN PA IS DRIFTING SOUTH...AND MAY BE A BOUNDARY CONTRIBUTOR THIS AFTERNOON/EVENING. CURRENT MCS THREAT TIMEFRAME IS OVERNIGHT AND/OR THURSDAY MORNING. EXPECT ISOLATED/WIDELY SCATTERED AIRMASS STORMS THIS AFTERNOON INTO THE EVENING. WLY/SWLY DOWNSLOPING FLOW WILL KEEP DEWPOINTS IN THE MID 60S AND ALLOW TEMPERATURES TO BE EVEN HIGHER THAN YESTERDAY. SEE CLIMATE SECTION BELOW. PREVIOUS... CONFIDENCE INCREASES TONIGHT AS A FRONTAL BOUNDARY THAT HAS BEEN DRAPED ACROSS THE GREAT LAKES EARLIER THIS WEEK MOVES SOUTH. MULTIPLE DISTURBANCES WILL ALSO CROSS THE REGION AND A MCS OR TWO WILL LIKELY MOVE ACROSS THE REGION LATE TONIGHT AND INTO THURSDAY. HIGH AMTS OF INSTABILITY WILL STILL BE IN PLACE AND SHEAR PROFILES WILL INCREASE. DMG WINDS AND LARGE HAIL WILL BE POSSIBLE IN LINE SEGMENTS AND BOW ECHOES. ACTIVITY WILL BE ONGOING THURSDAY MORNING AS THE FRONTAL BOUNDARY MOVES INTO SRN VA. SHOWERS AND THUNDERSTORMS ARE POSSIBLE THURSDAY AND ACTIVITY WILL BE CAPABLE OF GUSTY WINDS AND HEAVY RAIN. THE SEVERITY LEVEL IS IN QUESTION THURSDAY MORNING AND AFTERNOON SINCE ACTIVITY WEDNESDAY NIGHT MAY REDUCE INSTABILITY AMTS. HEAVY RAIN MAY CAUSE SOME LOCALIZED FLOODING ISSUES ESPECIALLY IN AREAS THAT HAVE SEEN HEAVY RAIN FROM THUNDERSTORMS IN THE PAST WEEK. && .SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY/... FRONTAL BOUNDARY WILL BE ORIENTED ACROSS THE CWA ROUGHLY FROM WEST TO EAST THURSDAY NIGHT...THEN RE-ORIENTS ITSELF FROM NORTHWEST TO SOUTHEAST DURING THE DAYTIME FRIDAY. CONVECTION IS LIKELY TO BE ONGOING THURSDAY EVENING GIVEN FRONT AND ALSO A SHORTWAVE TRAVELING IN NORTHWEST MID-LEVEL FLOW. SHOULD SEE A DOWNTREND IN CONVECTION OVERNIGHT THURSDAY....BUT WILL CONTINUE LOW POPS ACROSS THE SOUTHWEST CWA AS ANOTHER SHORTWAVE COULD KEEP SOME ACTIVITY GOING INTO THE NIGHT. HIGHEST POPS ON FRIDAY LOOK TO BE ALONG/SOUTHWEST OF THE FRONT WHICH WOULD ALSO COINCIDE WITH THE TRAJECTORY OF UPSTREAM SHORTWAVES. MORE CLOUDS WILL ALSO LIKELY TEMPER TEMPERATURES ON FRIDAY...MOST NOTABLY NORTHEAST OF THE FRONT INTO NORTH CENTRAL MARYLAND. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... FRONT WILL REMAIN STALLED OVER THE MID-ATLANTIC OVER THE WEEKEND WITH MINOR OSCILLATING MOVEMENTS. SHORTWAVES MOVING THROUGH IN NORTHWEST FLOW WILL ALSO CONTINUE TO BRING A CHANCE OF SHOWERS AND THUNDERSTORMS. ONE SHORTWAVE OF INTEREST MAY BE STRONG ENOUGH TO GENERATE A SURFACE LOW REFLECTION. IT/S UNCERTAIN WHETHER THIS WOULD BE FRIDAY NIGHT OR SATURDAY THEREFORE HAVE KEPT POPS IN THE CHANCE CATEGORY BOTH PERIODS FOR NOW BUT AN ENHANCED CHANCE OF CONVECTION MAY OCCUR DURING THIS TIME. IF THE SHORTWAVE IS STRONG ENOUGH THIS COULD PUSH THE FRONT FURTHER SOUTH OF THE CWA. BUT EVEN IF THIS HAPPENS...EXPECT A CONTINUATION OF CHANCE POPS GIVEN PERSISTENT NORTHWEST FLOW ALOFT. IN ADDITION...THAT BOUNDARY WILL EVENTUALLY LIFT BACK NORTH AS A WARM FRONT MAKING IT TOUGH TO RULE OUT CONVECTION ANY DAY IN THE LONG TERM. && .AVIATION /15Z WEDNESDAY THROUGH SUNDAY/... VFR CONDITIONS EXPECTED TODAY. WESTERLY WINDS WITH A FEW GUSTS TO 18 KTS POSSIBLE AT IAD-BWI-MTN-DCA-MRB. ISOLATED SHOWERS AND THUNDERSTORMS ARE POSSIBLE TODAY ACROSS THE TERMINALS. ACTIVITY WILL INCREASE IN COVERAGE TONIGHT AND INTO THURSDAY AS A FRONTAL BOUNDARY MOVES ACROSS THE REGION TONIGHT. MVFR/IFR CONDITIONS WILL BE POSSIBLE IN THUNDERSTORMS. OUTLOOK...COLD FRONT STALLS OVER THE AREA THROUGH THE WEEKEND...PROMOTING A CHANCE OF SHOWERS AND THUNDERSTORMS DURING THIS TIME. && .MARINE... SCA FOR WLY GUSTS UP TO 20 KT FOR NRN BAY AS WELL FORECAST TUESDAY EVENING SHIFT. ISOLATED SHOWERS AND THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON AND EVENING. MORE WIDESPREAD COVERAGE IS EXPECTED LATE TONIGHT AND INTO THURSDAY. SOME STORMS WILL PRODUCE GUSTY WINDS LIKELY RESULTING IN SMW ISSUANCE. STALLED BOUNDARY REMAINS THROUGH THE WEEKEND. NO SCA EXPECTED DURING THAT TIME. STRONG GUSTY WINDS WILL BE POSSIBLE IN SCATTERED THUNDERSTORMS THROUGH THE WEEKEND. && .CLIMATE... A RECORD HIGH TEMPERATURE WAS REPORTED AT REAGAN NATIONAL AIRPORT YESTERDAY. THE HIGH WAS 97 DEGREES AND THIS SURPASSES THE OLD RECORD OF 95 DEGREES SET IN 1991...1957...AND 1945. MORE RECORD HIGHS ARE EXPECTED TODAY AT DCA...AND POSSIBLE AT BWI AND IAD. THE LIST BELOW ARE THE RECORD HIGHS FOR THE THREE MAJOR AIRPORTS...KBWI...KDCA...AND KIAD. KBWI: RECORD HIGH: 97 IN 1957. KDCA: RECORD HIGH: 97 IN 1944. KIAD: RECORD HIGH: 94 IN 2007. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...NONE. VA...NONE. WV...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ530- 531-538-539. && $$ SYNOPSIS...BAJ/BPP/HAS NEAR TERM...BAJ/HAS SHORT TERM...BPP LONG TERM...BPP AVIATION...BAJ/BPP/HAS MARINE...BAJ/BPP/HAS CLIMATE...BAJ
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
725 AM CDT WED JUN 18 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 311 AM CDT WED JUN 18 2014 YET ANOTHER STORMY SHORT TERM PERIOD IS ON TAP WITH THIS PERIOD LOOKING TO CONTINUE THE TREAT FOR SEVERE WEATHER AND FLASH FLOODING. AT 4 AM...THE WARM FRONT WAS SPLAYED OUT FROM NEAR YANKTON ENE TO JUST NORTH OF I-90 IN SRN MN. YET ANOTHER ENHANCEMENT OF THE LLJ HAS PROVIDED ENOUGH ISENTROPIC LIFT TO OVERCOME THE CAP THE MOVED IN YESTERDAY TO ALLOW THUNDERSTORMS TO BLOSSOM ACROSS THE MN/IA BORDER REGION. STORMS IN THE MPX CWA HAVE REMAINED MAINLY ELEVATED...THOUGH STORMS ACROSS NRN IA HAVE BEEN ABLE TO BASICALLY MAINTAIN THEIR SFC CONNECTION...HENCE THE TORNADO THAT HAPPENED IN THE SPENCER AREA AFTER 1 AM. THOUGH NOT ROOTED AT THE SFC...PWATS NEAR 1.75" COMBINED WITH FREEZING LEVELS OVER 14K FEET HAS RESULTED IN RAINFALL RATES IN EXCESS OF 2 IN/HR OVERNIGHT. EXPECT THIS ACTIVITY TO SLOWLY DRIFT EAST WHILE WEAKENING OVER THE NEXT FEW HOURS AS THE LLJ BEGINS TO VEER OVER TO THE EAST AND WEAKEN THE REST OF THE MORNING. BASED ON THE HRRR AND RAP H85 MOISTURE TRANSPORT FORECAST...EXPECT THIS ACTIVITY TO HANG AROUND THROUGH ABOUT 15Z BEFORE WE GET INTO ANOTHER PRECIP BREAK THAT LOOKS TO LAST MOST OF THE AFTERNOON. MAIN QUESTION FOR THIS AFTERNOON IS WHERE WILL THE WARM FRONT SETUP. ACTIVITY RIGHT NOW WILL AGAIN FORCE THE WARM FRONT SOUTH INTO IA...LIKELY DOWN TO NEAR THE I-80 CORRIDOR. IN ADDITION TO THAT...IN THE WAKE OF THIS MORNINGS CONVECTION...THE RAP SHOWS THE 12C ISOTHERM AT H7 WORKING BACK UP INTO CENTRAL MN...WHICH WILL PUT A LID ON THINGS THROUGH THE AFTERNOON...MUCH LIKE WE JUST SAW YESTERDAY. LOOKING AT LLJ EVOLUTION...DURING THE AFTERNOON...IT WILL BACK TOWARD THE NORTHWEST AND STRENGTHEN ACROSS THE ERN DAKOTAS...WHICH WILL SHIFT THE FOCUS FOR THUNDERSTORMS FROM THE MS VALLEY BACK INTO THE DAKOTAS BY THE AFTERNOON. AS A RESULT...DELAYED ANY RAMP UP IN POPS TO LIKELIES UNTIL AFTER 00Z...TRYING ORIENT THINGS TOWARD THE NSSL/NMM/ARW WRFS...WHICH SHOW STORMS BLOSSOMING ONCE AGAIN AFTER 3Z. THIS IS IN CONJUNCTION WITH THE ARRIVAL OF THE WARM FRONT...WHICH LOOKS TO SURGE NORTH OUT OF IA THIS EVENING IN RESPONSE TO THE SFC LOW CURRENTLY OVER NE COLORADO WORKING OVER TO NEAR ABERDEEN TONIGHT. WHAT DOES THIS MEAN FOR THE SEVERE THREAT? WELL...ONE THING THAT IS FOR SURE IS INSTABILITY WILL NOT BE ISSUE...AS WE SHOULD SEE MLCAPES IN THE WARM SECTOR AGAIN PUSH 5000 J/KG. FOR A TORNADO THREAT...WE WOULD HAVE TO BANK ON ACTIVITY FORMING ALONG THE WARM FRONT AS IT MOVES NORTH. INSTEAD...FEEL OUR MAIN SEVERE THREAT WILL EXIST MAINLY OVERNIGHT WITH ANY SORT OF SYSTEM THAT COMES OUT OF THE DAKOTAS DURING THE AFTERNOON ALONG WITH STORMS THAT DEVELOP NORTH OF THE WARM FRONT AS IT WORKS INTO MN OVERNIGHT. DEEP LAYER SHEAR LOOKS TO BE MARGINALLY WEAKER WEDNESDAY GIVEN THE PRESENCE OF AN UPPER RIDGE...BUT THE STRONG INSTABILITY AND STEEP MID-LEVEL LAPSE RATES WILL BE MORE THAN ENOUGH TO KEEP A WIND/HAIL TREAT GOING THROUGH MUCH OF THE NIGHT. THERE WILL ALSO BE A CONTINUED FLASH FLOOD THREAT WITH THIS ACTIVITY AS WELL. DECIDED ON NOT ISSUING A FLASH FLOOD WATCH AT THIS TIME AS THERE IS ENOUGH UNCERTAINTY AS TO WHERE THIS ROUND OF HEAVY RAIN WILL SET UP THAT IT WAS TO DIFFICULT TO NARROW DOWN A CORRIDOR FOR WHERE ONE WOULD BE NEEDED. WITH THE 00Z CAMS...THERE IS A FAVORED CORRIDOR FOR HEAVY PRECIP FROM SE MN BACK NW TOWARD THE MN/ND/SD BORDER. HOWEVER...THIS WILL LIKELY CHANGE ONCE IT IS BETTER KNOWN WHERE THAT WARM FRONT SETS UP THIS EVENING. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 311 AM CDT WED JUN 18 2014 CONVECTION SHOULD BE ONGOING THURSDAY MORNING WITH A MODEST LLJ AND 925-850MB MOISTURE TRANSPORT ACROSS THE ENTIRE FORECAST AREA. A NW-SE ORIENTATED WARM FRONT SHOULD EXTEND ROUGHLY FROM FARGO...TO DAVENPORT...TO CHICAGO BY 12Z THURSDAY MORNING. THIS WILL BE THE FOCUS FOR SCATTERED TO NUMEROUS THUNDERSTORMS. PWATS SHOULD STILL BE RUNNING HIGH WITH 1.50-1.90" ACROSS THE FORECAST AREA AND THE MEAN STEERING WINDS INDICATE A SLOWER STORM MOTION...THEREFORE FLASH FLOODING WILL CONTINUE TO BE A THREAT. THE OVERALL RISK FOR SEVERE APPEARS FAIRLY LOW...BUT THERE IS ENOUGH DEEP LAYER SHEAR AND MODEST STABILITY TO PROVIDE A MINOR WIND AND HAIL THREAT. THE COLD FRONT AND GRADUALLY FILLING SURFACE LOW WILL EXTEND BACK TOWARD THE WEST IN THE CENTRAL AND NORTHERN PLAINS. THE FRONTAL BOUNDARIES WILL LOSE SOME OF THEIR DEFINITION AS THEY MOVE EAST...BUT A SLIGHTLY DRIER AIR MASS ENTERS WESTERN MN BY THURSDAY AFTERNOON AND EVENING. FRIDAY COULD ACTUALLY BE A DRY DAY ACROSS MOST OF MN WITH THE BOUNDARIES HAVING SHIFTED EAST INTO CENTRAL AND EASTERN WI AND THE LOW LEVEL FLOW BECOMING MUCH WEAKER. A WARM AND MAINLY ZONAL PATTERN SETS UP FOR THE WEEKEND...BUT THERE IS STILL A WEAK SURFACE TROUGH HANGING AROUND THE FORECAST AREA...SO WE CAN SIMPLY NOT GO WITH A DRY FORECAST. THE GOOD NEWS LOCALLY /BAD NEWS FOR SOGGY IA/ IS THAT THE NOCTURNAL LLJ FOCUSES SOUTH OF THE AREA FRI/SAT/SUN. THIS SUGGESTS A LOWER THREAT FOR HEAVY RAIN AND FLASH FLOODING. TEMPERATURES LOOK TO REMAIN NEAR OR ABOVE NORMAL THROUGH EARLY NEXT WEEK. THE 18.00Z ECMWF BRINGS A PSEUDO BACK DOOR COLD FRONT ACROSS THE AREA ON TUE-WED...BUT THE PAST COUPLE RUNS OF THE GFS DOES NOT SHOW IT AT THIS TIME. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING) ISSUED AT 647 AM CDT WED JUN 18 2014 WITH WIDESPREAD VFR CONDITIONS AND RAIN CLEARING THE WEST CENTRAL WI TAF SITES...LOOK FOR A FAIRLY QUIET AVIATION WEATHER DAY IN MN AND WESTERN WI. THE NEXT CHALLENGE IS DETERMINING PRECISELY WHERE...WHEN AND HOW INTENSE THE NEXT ROUND OF THUNDERSTORMS WILL BE THIS EVENING AND TONIGHT. IT LOOKS LIKE STORM INITIATION WILL OCCUR ALONG A LINE FROM WEST CENTRAL MN TO SOUTHEAST MN AND THEN SLOWLY MOVE NORTHEAST WITH TIME. THERE WILL ALSO BE STORMS DEVELOPING IN SD THAT WILL TRY AND HEAD EAST WITH TIME. KMSP... VFR EXPECTED THROUGH ROUGHLY 00Z. WE EXPECT ANOTHER LINE OF SCATTERED TO NUMEROUS SHOWERS AND STORMS THIS EVENING...MOST OF THE ACTIVITY SHOULD FORM SOUTH OF THE AIRPORT...BUT THE MOVEMENT COULD TAKE THESE STORMS NEAR THE AIRPORT FOR THE TAIL END OF THE EVENING COMMUTE. /OUTLOOK FOR KMSP/ FRI...VFR. MVFR SHRA/TSRA POSSIBLE. WINDS SW 10 KTS. SAT...VFR. MVFR SHRA/TSRA POSSIBLE. WINDS W 10 KTS. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ SHORT TERM...MPG LONG TERM...CLF AVIATION...CLF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
1004 AM CDT WED JUN 18 2014 .UPDATE... MINOR ADJUSTMENTS TO POPS FOR THIS AFTERNOON/EVENING. && .SHORT TERM... GENERALLY BENIGN EARLY SUMMER WEATHER PATTERN CONTINUES ACROSS THE REGION TODAY. AS EXPECTED...BETTER INFLUX OF LOW LEVEL MOISTURE HAS CONTINUED TO SHIFT MORE TO THE WEST OVER TX/LA AS DEEP ANTICYCLONE BUILDS IN FROM THE EAST. THIS HAS MEANT THAT VERY LITTLE MORNING STRATUS/FOG TODAY. 12Z SOUNDINGS SHOW PRECIPITABLE WATER VALUES AOB 1.5 INCHES WHICH GENERALLY ONLY SUPPORTS SPARSE DIURNAL CONVECTION AT THIS TIME OF YEAR WITHOUT SOME SORT OF SYNOPTIC FORCING. MODELS CONTINUE TO SHOW THAT A WEAK WAVE MOVING SW AROUND MID/UPPER LEVEL HIGH SHOULD PROVIDE ENOUGH ENERGY TO ALLOW FOR DEVELOPMENT OF SOME ISOLATED SHRA/TSRA OVER EASTERN SECTIONS OF AREA THIS AFTERNOON/EVENING. LATEST HRRR AND LOCAL WRF SHOW THIS DEVELOPMENT POTENTIALLY GETTING A BIT FARTHER WEST INTO THE I-55 CORRIDOR THAN PREVIOUSLY INDICATED...SO HAVE ADJUSTED POPS TO ALLOW FOR ISOLATED TSRA A BIT FARTHER WEST. OTHERWISE FORECAST LOOKS ON TRACK AND NO OTHER CHANGES MADE. /AEG/ && .AVIATION...VFR CONDITIONS WILL PREVAIL TODAY THROUGH TONIGHT. ISOLATED SHOWER/TSTM ACTIVITY WILL BE PRESENT ESPECIALLY IN THE EAST BUT TOO SPARSE TO INCLUDE IN THE TAFS AT THIS TIME. ANOTHER ROUND OF MVFR TO IFR CONDITIONS WILL BE POSSIBLE BEFORE SUNRISE THURSDAY MORNING. /28/ && .PRELIMINARY POINT TEMPS/POPS... JACKSON 92 71 93 71 / 11 9 20 10 MERIDIAN 93 68 93 69 / 20 10 26 15 VICKSBURG 91 70 92 70 / 7 6 15 10 HATTIESBURG 93 71 93 71 / 21 10 25 14 NATCHEZ 91 71 90 69 / 8 8 17 10 GREENVILLE 92 71 93 71 / 7 4 11 5 GREENWOOD 92 70 93 71 / 8 6 14 10 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...NONE. LA...NONE. AR...NONE. && $$ AEG/28
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
630 AM CDT WED JUN 18 2014 .SHORT TERM...(TODAY THROUGH FRIDAY) ISSUED AT 400 AM CDT WED JUN 18 2014 FORECAST CONCERNS THROUGH THE SHORT TERM WILL CONTINUE TO BE TRYING TO PIN DOWN THUNDERSTORM/SEVERE WEATHER CHANCES ALONG WITH THE HEAT ON WEDNESDAY. AN ISOLATED TORNADIC THUNDERSTORM INDEED DEVELOPED NEAR THE SOUTH DAKOTA BORDER THIS EVENING AND LASTED FOR SEVERAL HOURS OVER CEDAR COUNTY. THE 00Z OAX SOUNDING WAS IMPRESSIVE WITH CAPE OF NEARLY 6400 J/KG AND LITTLE CIN. ALSO OF NOTE WERE THE VERY STEEP LAPSE RATES AND H85 MOISTURE OF 17 DEG. C. A RARE 06Z SOUNDING WAS REQUESTED AND SHOWED AN UNSTABLE ATMOSPHERE WITH NEARLY 5000 J/KG OF CAPE AND 1.64 PWAT. EARLY THIS MORNING...THE MAIN CONVECTIVE COMPLEX IS OVER SOUTHERN MINNESOTA AND NORTHERN IOWA...CLOSER TO THE SURFACE AND H85 WARM FRONT. THE LOW LEVEL JET IS FORECAST TO REMAIN STRONG...40-50KTS OVER KANSAS AND MISSOURI THROUGH 15Z AND THERE IS AN APPROACHING H5 SPEED MAX. IT IS UNCERTAIN IF THIS LOW LEVEL JET CAN GET SOMETHING ELEVATED GOING OVER SOUTHEAST NEBRASKA AND SOUTHWEST IOWA. MOST OF THE OPERATIONAL MODELS ARE DRY THROUGH 21Z. THE EAX 4KM WRF HINTS AT SOMETHING IN THE MORNING ALONG WITH THE SREF. WILL LEAVE MOST OF THE FORECAST AREA DRY...HOWEVER WILL KEEP A SMALL POP IN FOR SOUTHWEST IOWA SHOULD SOMETHING ELEVATED MANAGE TO DEVELOP. THIS WILL NEED TO BE MONITORED THIS A.M. THIS AFTERNOON...THE HEAT BUILDS INTO THE FORECAST AREA WITH HIGHS AGAIN IN THE 90S. MEANWHILE...THE COLD FRONT IS FORECAST TO MOVE INTO CENTRAL NEBRASKA AND THE UPPER LEVEL SUPPORT MOVES INTO THE ROCKIES. THERE ARE A COUPLE OF LOCATIONS FOR CONVECTION...THE PRIMARY FOCUS APPEARS TO BE CLOSER TO THE HEIGHT FALLS...THE COLD FRONT AND THE DEEPENING SURFACE LOW. A SECOND AREA OF CONVECTION MAY DEVELOP IN IOWA AND BUILD BACK INTO THE FORECAST AREA. THE RAP SHOWS A CAP THIS MORNING WITH ELEVATED INSTABILITY AND DESTABILIZATION THIS AFTERNOON WITH THE EROSION OF THE CAP AFTER 20Z AND VERY STEEP LAPSE RATES WITH CAPE AROUND 3000 J/KG. THE NAM/GFS ARE MORE AGGRESSIVE WITH INSTABILITY WITH CAPE OF 4000-6000 J/KG. THE NAM HAS STRONGER DEEP LAYER SHEAR NEAR THE MISSOURI RIVER INTO WESTERN IOWA...WHILE THE GFS HOLDS THE STRONGER SHEAR TO THE WEST OF THE FORECAST AREA UNTIL AFTER MIDNIGHT. WITH HIGH INSTABILITY IN PLACE...SEVERE WEATHER WILL BE POSSIBLE WHERE STORMS DEVELOP. THE STORM PREDICTION CENTER HAS THE ENTIRE FORECAST AREA IN THE SLIGHT RISK AREA. WILL BEGIN TO INCREASE THUNDERSTORM CHANCES LATER THIS AFTERNOON AND CONTINUE TONIGHT AND THURSDAY AS THE UPPER LEVEL STORM SYSTEM MOVES INTO THE PLAINS AND DRIVES THE COLD FRONT THROUGH. WITH THE HIGH INSTABILITY AND FRONTAL BOUNDARIES THERE WILL BE A TORNADO THREAT. THE RAP HAS MORE OF A PRONOUNCED DRYLINE WORKING INTO CENTRAL AND NORTHEAST NEBRASKA. THE NAM HAS A DOUBLE WARMFRONT STRUCTURE WITH NORTHEAST NEBRASKA AND PARTS OF WEST IOWA ALONG WITH AREAS IN SD/MN WITH BACKED FLOW...WHILE THE GFS/EC IS FARTHER NORTH. PLACEMENT OF THESE FEATURES WILL BE KEY TO WHERE THE HIGHER TORNADO POTENTIAL IS. HAIL AND DAMAGING WINDS WILL BE POSSIBLE WITH THE CONVECTIVE COMPLEXES THAT DEVELOP TONIGHT AND THURSDAY. DEEP MOISTURE WITH PWATS OF 1.5 TO 2 INCHES RETURN AND LOCALLY HEAVY RAINFALL IS POSSIBLE...ESPECIALLY WHERE CONVERGENCE IS INCREASED IN THE VICINITY OF THE FRONTS. HIGH TEMPERATURES SHOULD TOP OUT IN THE 90S WITH HEAT INDEX VALUES AGAIN AROUND 100. THURSDAY/S HIGHS SHOULD BE IN THE 80S. THERE IS A BREAK IN THE RAIN CHANCES THURSDAY NIGHT...HOWEVER THE PUSH OF THE SHORTWAVE WEAKEN AND RETURN FLOW INCREASES WITH THE CHANCE FOR RAIN. .LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY) ISSUED AT 400 AM CDT WED JUN 18 2014 THE EXTENDED REMAINS UNSETTLED WITH AT OR BELOW NORMAL HIGHS IN THE 80S. && .AVIATION...(12Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 624 AM CDT WED JUN 18 2014 VFR CONDITIONS ARE FORECAST MUCH OF THE TAF PERIOD...WITH SCATTERED THUNDERSTORMS AND ATTENDANT MVFR/IFR CIGS/VSBYS POSSIBLE AFTER ABOUT 03Z. SOUTH WINDS WILL INCREASE INTO THE 15 TO 25KT RANGE BY MID MORNING AND CONTINUE THROUGH 00Z. A FRONTAL BOUNDARY MOVING INTO CENTRAL NEBRASKA LATE IN THE DAY WILL SPARK THUNDERSTORMS...WHICH WILL LIKELY MOVE INTO THE KOFK AREA BETWEEN 03Z AND 06Z...THEN TO KLNK AND KOMA AFTER 06Z. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ SHORT TERM...ZAPOTOCNY LONG TERM...ZAPOTOCNY AVIATION...DERGAN
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1025 AM EDT WED JUN 18 2014 .SYNOPSIS...A STRONG HIGH PRESSURE SYSTEM ALOFT WILL MAINTAIN HOT CONDITIONS ACROSS THE CAROLINAS AND SOUTHERN VIRGINIA THROUGH THURSDAY. IT WILL NOT BE AS HOT FRIDAY AND THE WEEKEND AS THE HIGH PRESSURE SYSTEM IS FORECAST TO WEAKEN. THIS WILL ALSO INCREASE THE CHANCE FOR SCATTERED AFTERNOON AND EVENING THUNDERSTORMS. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1025 AM WEDNESDAY... THE LATEST SURFACE ANALYSIS SHOWED SLIGHTLY WEAKER SURFACE RIDGING OVER CENTRAL NORTH CAROLINA...AND THE WATER VAPOR IMAGERY AS WELL AS THE 12Z UPPER-AIR ANALYSIS INDICATED A WEAK SHEAR AXIS OVER THE AREA...BETWEEN LOWER PRESSURE OFF OF THE SOUTHEAST COAST AND A WEAK MID-LEVEL RIDGE AXIS NEAR THE MOUNTAINS. OTHERWISE...CONDITIONS ARE SIMILAR TO MONDAY...WITH WEAK EFFECTIVE SHEAR...MIXED-LAYER CAPE THAT SHOULD RISE AT LEAST INTO THE 1000 TO 2000J/KG RANGE...AND DOWNDRAFT CAPE ON THE ORDER OF 1000J/KG. LIMITING FACTORS FOR DEEP CONVECTION WILL BE THE CONTINUED LACK OF GOOD LOW-LEVEL FORCING AND A SLIGHT INCREASE IN TEMPERATURES AROUND 500MB AS SHOWN BY THE RAP SOUNDINGS FOR THE AFTERNOON. MOST UNSTABLE ON THE RAP SOUNDINGS AND ITS INSTABILITY ANALYSES IS TOWARD KFAY...WHERE LIFTED INDICES ARE FORECAST TO -5C OR SO...AND ALSO WHERE THE RAP FORECASTS THE BETTER 850MB THETA-E. THE LATEST SPC MESOANALYSIS SHOWS THE HIGHER K INDICES THERE AS WELL AS OF MID MORNING. THE LATEST HRRR WRF WOULD...SIMILAR TO YESTERDAY...SHOW THE BETTER CHANCES OF DEEP CONVECTION RELATIVE TO THE REST OF CENTRAL NORTH CAROLINA MOSTLY SOUTH OF U.S. 64 AND CLOSER TO THE YADKIN RIVER...WITH LESSER CHANCES TO THE NORTHEAST WHERE STABILITY APPEARS GREATER AND MOISTURE SOMEWHAT LESS. STILL...AS WAS THE CASE MONDAY AFTERNOON...EVEN WHERE THE AIR MASS IS A LITTLE DRIER AN ISOLATED THUNDERSTORM CAN OCCUR...POSSIBLY WITH ENOUGH LIFT COURTESY OF THE PIEDMONT TROUGH AND MID-LEVEL SUPPORT FROM THE SHEAR AXIS. SLOW- MOVING CELLS COULD PRODUCE VERY LOCALLY HEAVY RAIN...AND IN THIS TYPE OF AIR MASS A BRIEF STRONG-TO-SEVERE WIND GUST FROM THE STRONGEST CELL IS POSSIBLE AS HAS BEEN THE CASE LATELY EACH AFTERNOON FROM A CELL OR TWO. 1000-850MB THICKNESSES SUPPORT HIGHS AT OR POSSIBLY SLIGHTLY ABOVE THE WARMER GUIDANCE...FOR HIGHS IN THE MID TO UPPER 90S...CLOSE TO THE RECORD AT KRDU. HEAT INDICES SHOULD BE HIGHEST TOWARD KGSB...KMEB...KFAY AND KCTZ WHERE THERE SHOULD BE A PERIOD WHERE THOSE VALUES CREEP JUST ABOVE 100. ANY LINGERING CONVECTION THIS EVENING WILL DIMINISH WITHIN AN HOUR OR TWO AFTER SUNSET. IN THEIR WAKE...EXPECT MOSTLY CLEAR-PARTLY CLOUDY SKIES. MIN TEMPS NEAR 70- LOWER 70S. && .SHORT TERM /THURSDAY AND THURSDAY NIGHT/... AS OF 315 AM WEDNESDAY... SUBTLE DIFFERENCES BEGIN TO APPEAR THIS PERIOD...NAMELY A GRADUAL WEAKENING OF THE MID-UPPER LEVEL RIDGE. OVERALL...THURSDAY WILL BE SIMILAR TO THE PAST FEW DAYS WITH HOT TEMPERATURES AND A SLIGHT CHANCE OF AN AFTERNOON THUNDERSTORM. LOW LEVEL THICKNESSES STILL SUGGEST MAX TEMPS IN THE MID AND POSSIBLY UPPER 90S. THE LOWERING UPPER LEVEL HEIGHTS WILL ALLOW A CONVECTIVE COMPLEX OVER THE OH VALLEY AND NORTHERN MID ATLANTIC TO DRIFT SOUTHWARD WITH TIME. OUTFLOWS FROM STORMS ASSOCIATED WITH THIS SYSTEM MAY TRIGGER SCATTERED THUNDERSTORMS THURSDAY NIGHT ACROSS ROUGHLY THE NE QUARTER OF CENTRAL NC. THIS IDEA BEING SHARED BY MOST OF THE MODEL GUIDANCE SO WILL INCREASE POPS TO 30-40 PERCENT ACROSS SECTIONS OF THE NE PIEDMONT AND NORTHERN COASTAL PLAIN...TRENDING TO LESS THAN 20 PERCENT ACROSS THE SOUTH. MIN TEMPS MAINLY IN THE LOWER 70S EXPECT NEAR 70 WHERE SKIES REMAIN MOSTLY CLEAR-PARTLY CLOUDY THROUGH THE OVERNIGHT. && .LONG TERM /FRIDAY THROUGH TUESDAY/... AS OF 3 AM WEDNESDAY... MEDIUM RANGE MODELS CONTINUE TO SUGGEST A TRANSITION FROM MID LEVEL RIDGING EXTENDING INTO THE AREA TO A BROAD MID LEVEL TROUGH LATE WEEK INTO THE WEEKEND... WITH NORTHWESTERLY TO WEST-NORTHWESTERLY MID LEVEL FLOW ALLOWING FOR HARD TO TRACK (AT THIS FAR OUT) S/W DISTURBANCES... HELPING TO ENHANCE CONVECTION. AT THE SURFACE... A WEAKENING SURFACE FRONT IS EXPECTED TO APPROACH THE REGION DURING THIS TIME FROM THE NORTH. DO NOT EXPECT THIS FRONT TO BE ABLE TO PUSH THROUGH THE AREA WITH ANY TRUE AIRMASS CHANGE GIVEN THE TIME OF YEAR. INSTEAD... THINK WE WILL SEE A SURFACE TROUGH SHARPEN SOME WITH THE ARRIVAL OF THE CYCLONIC FLOW AND POSSIBLY SLOWLY PUSH EASTWARD AND OR SOUTHWARD THROUGH THE AREA. TRYING TO PICK OUT WHEN THE BEST CHANCE FOR POPS WILL BE IS STILL DIFFICULT AT THIS TIME GIVEN THE TIMING OF HARD TO TRACK DISTURBANCE. HOWEVER... WILL CONTINUE TO TREND THE FORECAST LATE WEEK INTO THE WEEKEND TO 30-40 PERCENT CHANCE OF SHOWERS AND STORMS. THE BEST DEEP LAYER SHEAR WILL REMAIN TO THE NORTH... BUT COULD BE ENHANCED BY A PASSING DISTURBANCE. THUS... CANNOT RULE OUT SOME SEVERE STORMS EACH DAY...WITH THE MAIN THREAT OF DAMAGING WINDS ALONG WITH HEAVY RAIN. HIGH TEMPS WILL GO THROUGH A TRANSITION PERIOD AS WELL... LOW 90S NORTH TO UPPER 90S SOUTH ON FRIDAY... WITH MORE LOWER TO MID 90S DURING THE WEEKEND... WITH POSSIBLY SOME UPPER 80S NORTH. LOWS ARE EXPECTED TO GENERALLY BE AROUND 70/LOWER 70S. MEDIUM RANGE GUIDANCE BEGINS TO DIVERGE A BIT IN HOW THEY HANDEL THE NORTHEAST U.S. TROUGH. HOWEVER... AT THIS TIME THINK WE SHOULD AT LEAST SEE DIURNAL CHANCE FOR SHOWERS AND STORMS EITHER WAY. THUS... WILL CONTINUE CHANCE POPS FOR EACH AFTERNOON AND EVENING... WITH HIGH TEMPS GENERALLY IN THE LOWER 90S WITH MAYBE SOME MID 90S SOUTH. LOWS WILL REMAIN AROUND 70/LOWER 70S. && .AVIATION /14Z WEDNESDAY THROUGH SUNDAY/... AS OF 1025 AM WEDNESDAY... AN AREA OF HIGH PRESSURE ALOFT WILL MAINTAIN VFR CONDITIONS ACROSS CENTRAL NC THROUGH THURSDAY. SURFACE WINDS WILL BE LIGHT...LESS THAN 10KTS...FROM THE WEST-SOUTHWEST. DURING THE HEAT OF THE DAY...A FEW THUNDERSTORMS WILL OCCUR. HOWEVER...DUE TO EXPECTED LIMITED COVERAGE...CHANCES OF A STORM AFFECTING ANY PARTICULAR TERMINAL ARE TOO LOW TO MENTION IN THE FORECAST AT THIS TIME. CURRENTLY... RELATIVE TO THE REST OF CENTRAL NORTH CAROLINA...THE BETTER CHANCE OF ANY STORM WOULD BE TOWARD THE TRIAD AND KFAY...LEAST TOWARD KRWI. FOR FRIDAY AND INTO THE WEEKEND...THE AREA OF HIGH PRESSURE IS FORECAST TO WEAKEN. THIS WILL ALLOW DISTURBANCES IN THE FLOW ALOFT TO BRING A BETTER CHANCE FOR SCATTERED SHOWERS AND THUNDERSTORMS...ESPECIALLY IN THE AFTERNOON AND EVENING. IN ADDITION...AN INCREASING SOUTHERLY LOW LEVEL FLOW WILL INCREASE THE PROBABILITY OF LATE NIGHT AND EARLY MORNING FOG AND STRATUS...AND ASSOCIATED MVFR-IFR CONDITIONS...EACH MORNING STARTING FRIDAY. && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...WSS NEAR TERM...DJF/WSS SHORT TERM...WSS LONG TERM...BSD AVIATION...DJF/WSS
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1149 AM MDT WED JUN 18 2014 .UPDATE... ISSUED AT 1141 AM MDT WED JUN 18 2014 THE FRONTAL PASSAGE WHICH STALLED OVERNIGHT OVER NORTHWESTERN COLORADO FINALLY HAS GAINED FORWARD MOMENTUM AND IS TREKKING EAST. BANDS OF SHOWERS ARE POPPING UP ALONG THIS BOUNDARY AND WILL MOVE THROUGH SOUTHEASTERN UTAH AND WESTERN COLORADO THROUGH THE AFTERNOON. EXPECTING BEST CHANCE OF SHOWERS AND THUNDERSTORMS TO STILL BE OVER THE DIVIDE MOUNTAINS WHERE INSTABILITY AND MOISTURE IS BEST. THE WINTER WEATHER ADVISORY FOR THE EASTERN UINTA MOUNTAIN WAS CANCELLED AS SNOW HAS MOVED EAST OUT OF THE AREA. && .SHORT TERM...(TODAY THROUGH THURSDAY) ISSUED AT 324 AM MDT WED JUN 18 2014 DEEP UPPER LEVEL LOW OVER NORTHEAST IDAHO WILL LIFT NORTHEAST ACROSS MONTANA TODAY. THIS WILL HELP SWING SHRTWV ENERGY THROUGH THE FORECAST AREA LATER THIS MORNING AND THIS AFTERNOON. LIMITED MOISTURE FIELD WILL STILL BE ENOUGH TO SPARK SCATTERED SHOWERS AND THUNDERSTORMS THIS AFTERNOON...MAINLY ACROSS WESTERN COLORADO AS CONDITIONS DESTABILIZE WITH COOLING ALOFT. IN THE MEANTIME...SNOW SHOWERS ACROSS THE EASTERN UINTA MOUNTAINS AND HIGHER PEAKS IN EXTREME NORTHWEST COLORADO WILL CONTINUE THROUGH THIS MORNING...BEFORE TAPERING OFF AROUND 18Z PER LATEST HRRR GUIDANCE. WILL KEEP CURRENT WINTER WEATHER ADVISORY HIGHLIGHTS IN PLACE...WITH NO EXPANSION ANTICIPATED AS DEEPER POOL OF COLD AIR SHIFTS NORTHEAST INTO WYOMING...LEAVING THE NORTHERN MOUNTAINS IN WESTERN COLORADO WITH SNOW LEVELS OVER 12K. ELEVATED FIRE CONCERNS REMAIN IN PLAY ACROSS THE SOUTHWEST VALLEYS FROM CORTEZ EAST TO PAGOSA SPRINGS...AS THE COLD FRONT STALLS NEAR THE SAN JUANS. SO WILL KEEP RED FLAG WARNINGS IN PLACE. GUSTY WINDS SHOULD DIMINISH BY SUNSET...AND A FEW DAYTIME SHOWERS MAY LINGER INTO THE EVENING. A FINAL PV LOBE SWINGS ACROSS THE NORTH TOWARD MIDNIGHT BUT WITH INCREASING STABILITY AND SHRINKING MOISTURE...ONLY SOME CLOUDS ARE EXPECTED OVERNIGHT. WITH ENOUGH CLEARING...RADIATIONAL COOLING COULD ALLOW TEMPS TO DIP TO AROUND FREEZING IN THE CRAIG/MEEKER AREAS TONIGHT...WHERE A FREEZE WATCH REMAINS IN EFFECT. WEAKLY CYCLONIC FLOW CONTINUES ON THU WITH THE UPPER LOW OVER THE SASKATCHEWAN/MONTANA BORDER. AIR REMAINS DRY FOR LITTLE OTHER THAN SOME HIGH CLOUDS ACROSS THE NORTH. TEMPERATURES BEGIN TO MODERATE THU. .LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY) ISSUED AT 324 AM MDT WED JUN 18 2014 DRY AIR REMAINS THE MAJOR PLAYER FOR ERN UT/WRN CO THU NIGHT AND FRI. GFS/ECMWF SHOW SOME 500-300 MB PAC MOISTURE REACHING OUR AREA IN THE FORM OF HIGH CLOUDS FRI AFTERNOON IN WESTERLY FLOW. TEMPS CONTINUE TO REBOUND FROM THE MIDWEEK COOLDOWN. FAIRLY QUIET PERIOD CONTINUES THROUGH TUESDAY WITH TEMPERATURES CLIMBING TO THE PLUS SIDE OF NORMAL AS WE MOVE THROUGH THE WEEKEND. CONDITIONS LOOK DRY UNDER A RIDGE OF HIGH PRESSURE...BUT CANNOT RULE OUT AN ISOLATED STORM OVER THE HIGH COUNTRY MONDAY AND TUESDAY AS A SMIDGEN OF MOISTURE WORKS IN UNDER THE RIDGE. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 1141 AM MDT WED JUN 18 2014 GUSTY CONDITIONS WILL OCCUR WITH THE PASSING OF A SECONDARY COLD FRONT WHICH IS NOW MOVING EASTWARD ACROSS WESTERN COLORADO AND VERY SOUTHEASTERN UTAH. WINDS AT VALLEY SITES ARE NOT EXPECTED TO GUST HIGHER THAN 20-25 MPH...BUT WILL LIKELY BE HIGHER AT MOUNTAIN TAF SITES NEAR VIRGA AND THUNDERSTORMS. EXPECT A MAJOR DOWNTURN IN SHOWER ACTIVITY IN EASTERN UTAH AFTER 21Z THIS AFTERNOON AND AFTER 00Z IN WESTERN COLORADO THIS EVENING. && .FIRE WEATHER... ISSUED AT 324 AM MDT WED JUN 18 2014 A RED FLAG WARNING REMAINS IN EFFECT FOR FIRE WEATHER ZONE 207 BELOW 9500 FEET BETWEEN NOON AND 700 PM MDT TODAY FOR CONTINUED GUSTY WEST TO SOUTHWEST WINDS AND LOW HUMIDITY. THE COLD FRONT WILL CLEAR THE AREA THIS EVENING...AND WINDS ARE EXPECTED TO DECREASE BEHIND THIS FRONTAL PASSAGE. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...RED FLAG WARNING UNTIL 7 PM MDT THIS EVENING FOR COZ207. FREEZE WATCH FROM LATE TONIGHT THROUGH THURSDAY MORNING FOR COZ002. UT...NONE. && $$ UPDATE...JAM SHORT TERM...JDC/JAD LONG TERM...JAD/JDC AVIATION...JAM FIRE WEATHER...JDC
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
230 PM EDT WED JUN 18 2014 .SHORT TERM...TONIGHT THRU FRIDAY NIGHT... AXIS OF ATLC HIGH PRESSURE RIDGE SITS OFF THE GEORGIA COAST THIS AFTN WITH VERY WEAK ONSHORE/EASTERLY FLOW IN PLACE. WITH THE RIDGE AXIS IN PLACE THERE WILL BE LIMITED CONVECTION OVER SE GA WITH A MUCH DRIER AIRMASS IN PLACE. ACROSS NE FLORIDA THE SEABREEZE HAS KICKED IN. THE BEST MOISTURE (1.4" PW) AND SCATTERED CONVECTION IS FORECAST TO BE SOUTH OF A LINE FROM GREEN COVE SPRINGS TO SUWANNEE SPINGS WITH 12Z JAX SOUNDING AT A MEAGER 1.25" PW. THE ACTIVITY WILL LIKELY INCREASE IN AREAL COVERAGE AS IT PUSHES WESTWARD THROUGH THE AFTERNOON INTO THE VERY EARLY EVENING AND SHIFT TOWARD THE I-75 CORRIDOR IN THE LATE IN THE DAY WHERE HIGHER TSTM CHANCES SHIFT ALONG THE SEA BREEZE. DIURNAL INFLUENCES SHOULD KICK IN THIS EVENING WITH TSTMS/DAYTIME HEATING WANING AND SKIES CLEARING. WITH NEAR SFC MOISTURE IN PLACE IN CONCERT WITH DRY MID LEVELS...PATCHY FOG MAY BE POSSIBLE...BUT CONFIDENCE IS LOW WITH 10Z RAP DEPICTION SHOWING VERY LITTLE IN THE WAY OF FOG...BUT MORE CONFINED TOWARDS SW FLORIDA. ON THURSDAY...MOISTURE ASSOCIATED WITH AN UPPER LEVEL TROUGH/LOW PRESSURE AREA/ASSOCIATED VORT LOBE OVER THE SOUTHERN HALF OF FLORIDA PUSHES NORTHWARD. SUBSEQUENTLY RAIN CHANCES ACROSS SOUTHERN AREAS OF NORTHEAST FLORIDA WITH PWS RISING BETWEEN 1.60 TO ABOUT 1.80 INCHES BY LATE THURSDAY ACROSS THE SOUTHERN TIER OF THE CWA. HENCE...HAVE STRATIFIED POPS GRADIENT WITH 50% CHANCES ACROSS NORTH CENTRAL FLORIDA AND 20-30 POPS ACROSS THE ST. MARY`S RIVER TO TEEN CHANCES ACROSS THE ALTAMAHA. RIDGE OF HIGH PRESSURE REMAINS OVER THE AREA FRIDAY AND FRIDAY NIGHT...WITH SEA BREEZES LEADING TO WIDELY SCATTERED AFTERNOON/EVENING SHOWERS/T-STORMS...WITH SLIGHTLY GREATER COVERAGE EXPECTED SOUTH OVER N-CTRL FL WHERE GREATER MOISTURE WILL BE. ANOTHER HOT DAY FRI WITH LOW-MID 90S INTERIOR PORTION...AROUND 90 COASTAL COUNTIES EXCEPT UPPER 80S IMMEDIATE COAST. .LONG TERM...SATURDAY THRU TUESDAY... CHANCE OF AFTERNOON/EVENING SHOWERS/T-STORMS SAT/SUN WITH SEA BREEZES AND WEAK SURFACE TROF OVER SRN GA. HOT WEEKEND TEMPS WITH HI TEMPS LOW-MID 90S INLAND...AROUND 90 COAST...WITH LOW TEMPS IN LOW-MID 70S. WEAK ZONAL FLOW PATTERN OVER THE AREA EARLY NEXT WEEK WITH SCATTERED AFTERNOON/EVENING SHOWERS/T-STORMS EACH DAY PARTICULARLY ALONG SEA BREEZES AND OUTFLOW BOUNDARIES CREATED BY INITIAL STORMS THAT DEVELOP. LITTLE CHANGE IN TEMPERATURES WITH HIGHS AROUND 90 COAST...LOW-MID 90S INLAND AND LOWS IN THE LOW-MID 70S. && .AVIATION... TERMINALS EAST OF I-95 WILL HAVE VFR CONDITIONS THRU 18Z...WITH KGNV HAVING A POSSIBLE VCNTY TSTM BETWEEN 20-01Z THIS AFTN/EVE. PATCHY FOG IS EXPECTED AT KVQQ DURING THE PREDAWN HOURS AND VERY EARLY DAYLIGHT HOURS FOG INTERMITTENTLY REDUCING VSBYS TO MVFR. TOMORROW BEST CONVECTION WILL BE CONFINED TO THE SOUTHERN TIER OF JAX CWA WITH KGNV POSSIBLY HAVING TEMPO BKN CIG BASES OF 015-020 AGL THU AFTN BETWEEN 20-24Z. THURSDAY...TEMPORARY MVFR RESTRICTIONS WL BE POSSIBLE AT KGVN WITH SCT TSRA PERHAPS BRIEFLY FURNISHING IFR CONDS AND GUSTY WINDS FROM 20Z TO 01Z. && .MARINE...BENIGN CONDITIONS WILL PERSIST THROUGH FRIDAY WITH WEAK HIGH PRESSURE OVER THE AREA...RESULTING IN WIND SPEEDS GENERALLY 10 KTS OR LESS AND SEAS 2-3FT. THE HIGH WILL MOVE FARTHER OFFSHORE FRIDAY NIGHT THROUGH THE WEEKEND WHILE LOW PRESSURE DEVELOPS OVER THE MID ATLANTIC REGION...LEADING TO SOMEWHAT STRONGER SOUTHERLY FLOW OVER THE WATERS...BUT REMAINING BELOW ADVISORY CRITERIA. RIP CURRENTS: LOW RISK IS EXPECTED THROUGH FRIDAY. && .PRELIMINARY POINT TEMPS/POPS... AMG 92 69 93 70 / 10 10 10 10 SSI 85 74 86 75 / 10 10 10 10 JAX 89 70 89 70 / 10 10 20 10 SGJ 84 72 85 74 / 20 20 30 10 GNV 89 69 90 69 / 40 20 50 30 OCF 89 69 90 70 / 40 20 50 40 && .JAX WATCHES/WARNINGS/ADVISORIES... FL...NONE. GA...NONE. AM...NONE. && $$ WOLF/CORDERO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
131 PM CDT WED JUN 18 2014 .DISCUSSION... 944 AM CDT A LINE OF SHOWERS AND STORMS IS MOVING TROUGH NORTH CENTRAL ILLINOIS THIS MORNING. ON IR SATELLITE...IN GENERAL THE SYSTEM IS WARMING ALOFT BUT ISOLATED STORMS ARE SHOWING PERIODIC STRENGTHENING. LAPSE RATES ALOFT WILL CONTINUE TO SUPPORT THUNDERSTORMS BUT IN GENERAL THINKING THE ATMOSPHERE IS TOO STABLE FOR SEVERE STORMS. MAY SEE AN ADDITIONAL STORM OR TWO PULSE UP AND PRODUCE SPECIAL WEATHER STATEMENT WORTHY GUSTS...BUT IN GENERAL EXPECTING THE LINE TO GRADUALLY DECLINE AS IT MOVES THROUGH NORTHERN IL AND NW INDIANA. WITH THE EXTENSIVE CLOUD COVER OVERHEAD...HAVE VERY LOW CONFIDENCE IN THE FORECAST FOR THIS AFTERNOON. NO GUIDANCE MEMBER HAS PICKED UP THIS MORNING/S LINE OF STORMS. IF THE CLOUDS STICK AROUND...IT WILL BE VERY DIFFICULT TO DESTABILIZE AND COULD SEE A COOLER AND DRIER DAY THAN EXPECTED. BUT IF CLOUDS THIN OUT BEHIND THE STORMS...HOT CONDITIONS AND SCATTERED STORM DEVELOPMENT IS MORE LIKELY. THE CLOUDS ARE THINNING OVER IOWA THIS MORNING SO FOR NOW DECIDED TO KEEP A CHANCE OF THUNDER GOING IN THE FORECAST. GIVEN THE STATIONARY BOUNDARY TO OUR NORTH...KEPT THE GREATEST CHANCE ALONG THE IL/WI STATE LINE. JEE && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 18Z... * WIND DIRECTION AND SPEED TRENDS THROUGH THIS EVENING...WITH NORTHEAST WINDS AROUND 10 KT LIKELY RETURNING LATE AFTN/EARLY EVE. * ADDITIONAL SHRA/TSRA POTENTIAL THIS EVENING/TONIGHT AND ON THURSDAY. * CHANCE FOR LOWER CIGS TONIGHT. * EAST-NORTHEAST WINDS ON THURSDAY. RC //DISCUSSION...UPDATED 18Z... LARGE TSRA COMPLEX HAS PUSHED SOUTH OF THE TERMINALS...LEAVING A VERY CHAOTIC WIND FIELD IN ITS WAKE. THIS COMPLEX HAS ALSO STABILIZED THE AIR MASS OVER THE AREA AND THROWN INTO DOUBT CONVECTIVE TRENDS THE REMAINDER OF THE DAY INTO TONIGHT. IF THE ATMOSPHERE CAN CLEAR AND RECOVER ENOUGH...ANOTHER SHORTWAVE MAY TOUCH OFF TSRA EARLY THIS EVENING. HAVE MAINTAINED TEMPO GROUP IN TAFS FOR NOW...BUT ITS CONCEIVABLE THAT CHANCES FOR ADDITIONAL TSRA HAVE BEEN GREATLY REDUCED BY THE STORMS THAT HAVE ALREADY MOVED THROUGH. WINDS ARE GENERALLY SOUTHEAST OUT TOWARD RFD...BUT HAVE VERY LOW CONFIDENCE IN WIND TRENDS INTO THE LATE AFTERNOON FOR THE EASTERN TERMINALS. THERE IS A GOOD DEAL OF VARIABILITY IN OBSERVED WINDS IN NE IL...NW IN AND SRN WI...BUT OVERALL SPEEDS HAVE COME DOWN AND SHOULD BE FAIRLY LIGHT. A SHIFT TO STRONGER NORTHEAST WINDS AROUND 10 KT IS STILL EXPECTED LATE THIS AFTERNOON INTO THE EARLY EVENING FOR THE EASTERN TAF SITES. SOME GUIDANCE INDICATES POTENTIAL FOR LOWER CIGS TONIGHT...BUT HAVE NOT INCLUDED ANY MVFR OR IFR IN THE TAF. ON THURSDAY...WINDS ARE EXPECTED TO BE EAST AND NORTHEAST CLOSER TO LAKE MICHIGAN AND SOUTHEAST IN NORTH CENTRAL IL. COULD SEE SPEEDS AROUND OR OVER 10 KT AT TIMES AT ORD/MDW/GYY. THE AIR MASS OVER THE AREA WILL REMAIN UNSTABLE ESPECIALLY ALOFT...SO AN UPPER LEVEL DISTURBANCE MAY BE ABLE TO TOUCH OFF ANOTHER ROUND OF SHRA/TSRA. HAVE INCLUDED A PROB30 GROUP IN THE TAF...WITH FAIRLY LOW CONFIDENCE IN TIMING AND COVERAGE. BETTER TSRA CHANCES COULD END UP MAINLY AWAY FROM LAKE MI...INCLUDING RFD AREA...DUE TO MARINE INFLUENCE EXPECTED CLOSER TO THE LAKE. RC //ORD AND MDW CONFIDENCE...UPDATED 18Z... * LOW IN WIND DIRECTION TRENDS THROUGH MID AFTERNOON...MEDIUM IN SHIFT TO NORTHEAST WINDS AROUND 10 KT LATE THIS AFTERNOON. * LOW IN TSRA TRENDS THE REMAINDER OF THE PERIOD. * HIGH IN EAST-NORTHEAST WINDS ON THURSDAY...MEDIUM IN SPEEDS. RC //OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z... THURSDAY NIGHT THROUGH TUESDAY...PRIMARILY VFR WITH PERIODIC CHANCES FOR THUNDERSTORMS. BMD && .MARINE... 247 AM CDT A FRONTAL BOUNDARY WILL LINGER IN THE VICINITY OF LAKE MICHIGAN THROUGH THE REMAINDER OF THE WEEK. IN GENERAL...SOUTH WINDS ARE EXPECTED SOUTH OF THE BOUNDARY WITH NORTHEAST WINDS NORTH OF THE BOUNDARY. THE FRONT IS EXPECTED TO SAG SOUTH ACROSS LAKE MICHIGAN TODAY...THEN LIFT BACK NORTH AGAIN THURSDAY INTO FRIDAY. HIGH PRESSURE WILL BUILD JUST EAST OF LAKE MICHIGAN LATE IN THE WEEK INTO THE WEEKEND AND SHOULD RESULT IN RELATIVELY MODEST WINDS ACROSS THE LAKE THIS WEEKEND INTO EARLY NEXT WEEK. BMD && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion National Weather Service Lincoln IL 108 PM CDT Wed Jun 18 2014 .DISCUSSION... ISSUED 1045 AM CDT Wed Jun 18 2014 A line of storms has reached Knox county and will be moving into an unstable airmass with decreasing CIN and CAPE values approaching 3000 J/kg. Expect the line to move primarily east as individual storms drift southeast. Based on HRRR 3km and NCEP 4km output, it appears the southern extent of the line as it progresses east should generally remain north of a line from Rushville to Lincoln to Champaign. We kept daytime chance PoPs confined to that general area. That line it projected to remain sub-severe for the most part during the day. Severe potential looks higher tonight as a complex of storms develops to our north along the stationary front and rides over the upper level ridge into N IL this evening. That complex is projected to curve to the ESE tonight and dissipate as it reaches Lincoln to Champaign shortly after midnight. Varying solutions high resolution models lead to lower confidence on any one solution, but that appears to be closer to the consensus at this point. Temperatures today will climb into the lower 90s in most areas. The current line of storms will produce a cold pool that will spread across the northern third of counties, but some sun later this afternoon should boost even those areas back toward the low 90s. Dewpoints will reside in the low 70s all day as well, making for very humid conditions. Heat index readings will approach 100 degrees in areas that remain sunny through the day, mainly south of Lincoln. Updates this morning were mainly to the weather and PoP grids, with minor adjustments to temps. Updated info will be available shortly. Shimon && .AVIATION... ISSUED 100 PM CDT Wed Jun 18 2014 Line of storms will affect PIA between 18z and 19z, mainly with heavy rains of 0.75" in less than an hour. BMI should also be affected between 19z and 20z with similar conditions. Visibility in the heavy rain could drop to less than a mile for a short time. A 1sm +TSRA was included in a tempo for the heavy rain potential. Ceiling heights should generally stay MVFR even during thunderstorms. CMI, SPI and DEC will have a better chance of remaining dry through the afternoon. Another complex of storms is projected to develop in N IL later this afternoon and evening and move south across our terminal sites overnight. Timing and coverage of that complex is not handled well in any of the short term models, so VCTS was included for now until closer to this evening. Rain chances will exist all night at the terminals as a frontal boundary slowly sags south into C IL. Thursday morning should see a decrease in coverage, especially after sunrise. Winds will remain southwest at 12g20kt until evening then shift south and diminish below 10kt. SSW winds will increase again to around 10kt after sunrise Thursday. Shimon && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1125 AM CDT WED JUN 18 2014 .DISCUSSION... 944 AM CDT A LINE OF SHOWERS AND STORMS IS MOVING TROUGH NORTH CENTRAL ILLINOIS THIS MORNING. ON IR SATELLITE...IN GENERAL THE SYSTEM IS WARMING ALOFT BUT ISOLATED STORMS ARE SHOWING PERIODIC STRENGTHENING. LAPSE RATES ALOFT WILL CONTINUE TO SUPPORT THUNDERSTORMS BUT IN GENERAL THINKING THE ATMOSPHERE IS TOO STABLE FOR SEVERE STORMS. MAY SEE AN ADDITIONAL STORM OR TWO PULSE UP AND PRODUCE SPECIAL WEATHER STATEMENT WORTHY GUSTS...BUT IN GENERAL EXPECTING THE LINE TO GRADUALLY DECLINE AS IT MOVES THROUGH NORTHERN IL AND NW INDIANA. WITH THE EXTENSIVE CLOUD COVER OVERHEAD...HAVE VERY LOW CONFIDENCE IN THE FORECAST FOR THIS AFTERNOON. NO GUIDANCE MEMBER HAS PICKED UP THIS MORNING/S LINE OF STORMS. IF THE CLOUDS STICK AROUND...IT WILL BE VERY DIFFICULT TO DESTABILIZE AND COULD SEE A COOLER AND DRIER DAY THAN EXPECTED. BUT IF CLOUDS THIN OUT BEHIND THE STORMS...HOT CONDITIONS AND SCATTERED STORM DEVELOPMENT IS MORE LIKELY. THE CLOUDS ARE THINNING OVER IOWA THIS MORNING SO FOR NOW DECIDED TO KEEP A CHANCE OF THUNDER GOING IN THE FORECAST. GIVEN THE STATIONARY BOUNDARY TO OUR NORTH...KEPT THE GREATEST CHANCE ALONG THE IL/WI STATE LINE. JEE && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 16Z... * LINE OF TSRA MOVING THROUGH TERMINALS. * ADDITIONAL TSRA POTENTIAL LATER THIS AFTERNOON INTO THIS EVENING. * WIND TRENDS THROUGH THE REMAINDER OF THE DAY. RC //DISCUSSION...UPDATED 16Z... TSRA COMPLEX CURRENTLY MOVING THROUGH THE TERMINALS WITH DROP TO IFR/LOWER MVFR VSBY AND STRONG NORTH-NORTHWEST GUSTS APPROACHING 30 KT ON LEADING EDGE. LOW CONFIDENCE IN WIND TRENDS BEHIND THE COMPLEX...WITH SITES ACROSS NORTH CENTRAL ILLINOIS HAVING SHIFTED TO EAST-NORTHEAST. WINDS MAY EVENTUALLY TURN VARIABLE AFTER A FEW HOURS DUE TO DISRUPTION OF WIND FIELD. THE CURRENT CONVECTION ALSO THROWS DOUBT INTO HOW CONVECTION WILL EVOLVE THE REMAINDER OF THE DAY...WITH IT LIKELY TAKING LONGER FOR THE ATMOSPHERE TO DESTABILIZE AGAIN. HAVE MAINTAINED TEMPO TSRA GROUP FROM 00Z TO 04Z FOR NOW. RC FROM 12Z... ANOTHER DAY OF PRIMARILY VFR CONDITIONS ON TAP WITH A GREAT DEAL OF UNCERTAINTY SURROUNDING THUNDERSTORMS CHANCES. THIS MORNING...A FRONTAL BOUNDARY IS DRAPED NEAR THE IL/WI STATE LINES WITH OVERNIGHT CONVECTION OCCURRING NORTH OF THE FRONT. FARTHER WEST...AN AREA OF MORE ROBUST THUNDERSTORMS IS PUSHING EAST ACROSS NORTHERN IOWA THOUGH HAS SHOWN SOME SIGNS OF WEAKENING AND EXPECT THIS TREND TO CONTINUE THROUGH THE MORNING. THUNDERSTORMS ARE CURRENTLY NOT EXPECTED TO MAKE IT INTO RFD BUT REMNANT SHOWERS MAY PERSIST PUSHING THROUGH STARTING IN THE 14-15Z HOUR. MODERATE TO STRONG INSTABILITY IS ONCE AGAIN PROGGED TO DEVELOP ACROSS THE REGION TODAY AND WILL BE CAPPED EARLY IN THE DAY THOUGH THE CAP STARTS TO ERODE MID AFTERNOON. THERE IS LITTLE IN THE WAY OF UPPER LEVEL SUPPORT WITH EVEN WEAK MID LEVEL HEIGHT RISES BUILDING OVER THE AREA THIS AFTERNOON THAT MIGHT HELP SUPPRESS NEW GROWTH. CHANCES FOR THUNDERSTORM DEVELOPMENT THIS AFTERNOON ARE NOT ZERO BUT LOW ENOUGH TO PRECLUDE ANY REFERENCE IN THE TAFS. THE BEST CHANCES APPEAR TO BE LATE AFTERNOON INTO THE EVENING AS THE FRONT SAGS SOUTH INTO THE AREA...THOUGH MAY COME THROUGH QUICKER IN FAR NORTHEAST ILLINOIS AS AN ENHANCED LAKE BREEZE. WITH THE CAP FAIRLY WEAK AT THIS POINT...THIS MAY SERVE THE FOCUS FOR MORE WIDESPREAD THUNDERSTORM DEVELOPMENT. WINDS SHOULD GRADUALLY VEER BACK AROUND TO THE SOUTHEAST LATE TONIGHT INTO EARLY THURSDAY AS THE WARM FRONT LIFTS BACK TO THE NORTH. BMD //ORD AND MDW CONFIDENCE...UPDATED 16Z... * HIGH IN CURRENT LINE OF TSRA CLEARING ORD SHORTLY AND MDW BY 17-1730Z. * LOW CONFIDENCE IN WIND TRENDS THE REMAINDER OF THE DAY. * LOW CONFIDENCE IN TSRA TRENDS THIS AFTERNOON INTO THIS EVENING. RC //OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z... THURSDAY NIGHT THROUGH TUESDAY...PRIMARILY VFR WITH PERIODIC CHANCES FOR THUNDERSTORMS. BMD && .MARINE... 247 AM CDT A FRONTAL BOUNDARY WILL LINGER IN THE VICINITY OF LAKE MICHIGAN THROUGH THE REMAINDER OF THE WEEK. IN GENERAL...SOUTH WINDS ARE EXPECTED SOUTH OF THE BOUNDARY WITH NORTHEAST WINDS NORTH OF THE BOUNDARY. THE FRONT IS EXPECTED TO SAG SOUTH ACROSS LAKE MICHIGAN TODAY...THEN LIFT BACK NORTH AGAIN THURSDAY INTO FRIDAY. HIGH PRESSURE WILL BUILD JUST EAST OF LAKE MICHIGAN LATE IN THE WEEK INTO THE WEEKEND AND SHOULD RESULT IN RELATIVELY MODEST WINDS ACROSS THE LAKE THIS WEEKEND INTO EARLY NEXT WEEK. BMD && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion National Weather Service Lincoln IL 1055 AM CDT Wed Jun 18 2014 .DISCUSSION... ISSUED 1045 AM CDT Wed Jun 18 2014 A line of storms has reached Knox county and will be moving into an unstable airmass with decreasing CIN and CAPE values approaching 3000 J/kg. Expect the line to move primarily east as individual storms drift southeast. Based on HRRR 3km and NCEP 4km output, it appears the southern extent of the line as it progresses east should generally remain north of a line from Rushville to Lincoln to Champaign. We kept daytime chance PoPs confined to that general area. That line it projected to remain sub-severe for the most part during the day. Severe potential looks higher tonight as a complex of storms develops to our north along the stationary front and rides over the upper level ridge into N IL this evening. That complex is projected to curve to the ESE tonight and dissipate as it reaches Lincoln to Champaign shortly after midnight. Varying solutions high resolution models lead to lower confidence on any one solution, but that appears to be closer to the consensus at this point. Temperatures today will climb into the lower 90s in most areas. The current line of storms will produce a cold pool that will spread across the northern third of counties, but some sun later this afternoon should boost even those areas back toward the low 90s. Dewpoints will reside in the low 70s all day as well, making for very humid conditions. Heat index readings will approach 100 degrees in areas that remain sunny through the day, mainly south of Lincoln. Updates this morning were mainly to the weather and PoP grids, with minor adjustments to temps. Updated info will be available shortly. Shimon && .AVIATION... ISSUED 637 AM CDT Wed Jun 18 2014 A very challenging forecast, as convection will be dictated by various residual outflow boundaries plus a surface front across northern Illinois that may drift south a bit tonight. With the various synoptic and high-resolution models showing a wide variety of solutions, confidence on thunder elements of the TAF set is lower than usual. Have generally gone with VCTS mentions with a PROB30 group this evening to try and highlight a more likely time frame of any temporary MVFR conditions, based on the output of the ARW and NMM models. Kept KSPI/KDEC dry into early evening, but isolated showers/storms may occur earlier as well. Geelhart && .PREV DISCUSSION... ISSUED 330 AM CDT Wed Jun 18 2014 SHORT TERM...Today through Friday night Will issue another special weather statement to address the heat and humidity today and Thursday with highs around 90F and heat indices peaking from 95 to 100F similar to what we experienced yesterday. Strong upper level ridge (592 dm 500 mb high pressure over the southeast states) has been keeping much of central and southeast IL dry with the heat and humidity. MCS`s bringing more strong to severe thunderstorms with heavy rains north of IL over MN/WI and northern IA early this morning. These MCS`s forming on nose of low level jet interacting with frontal boundary draped over southern Great Lakes and upper MS river valley and extends to 999 mb low pressure in NE CO. Strong 558 dm 500 mb low was along the ID/MT border with series of MCS east of it from SD into the southern Great Lakes. Upper level low near ID/MT border to lift NE into southern Saskatchewan by sunset Thu while short waves to weaken top of upper level ridge and increase chances of convection over central IL from north to south from this afternoon through next few days as frontal boundary sags back south toward central IL by Friday. Most areas will still be dry this morning with isolated convection developing in the tropical air mass this afternoon especially northern areas. RAP and HRRR models also show some qpf in far SE IL from Lawrenceville SE this afternoon. SPC has shifted slight risk of severe storms further south tonight to included most of central IL with just southern six counties not in slight risk. Highest risk of severe storms still appears north of Peoria where 30% risk of large hail and damaging wind gusts where best bulk shear in combination with moderate to strong instability. Highest convection chances of 50-60% over northern counties from tonight through Thu night shift further south during Friday with frontal boundary. SPC keeps slight risk NW of CWA Thu afternoon & Thu night especially over IA. LONG TERM...Saturday through Tuesday night Central IL gets into a WNW upper level flow during the weekend into early next week with disturbances tracking ESE over top of ridge across the Midwest and interacting with a humid air mass to trigger daily chances of showers and thunderstorms. An upper level trof digging into the Midwest Monday afternoon and Monday night to drive a cold front SE into IL Monday night and increase chances of showers and thunderstorms then with gradually cooler air by Tue. 07 && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
141 PM EDT WED JUN 18 2014 .SYNOPSIS... ISSUED AT 422 AM EDT WED JUN 18 2014 PERIODS OF SHOWERS AND THUNDERSTORMS WILL REMAIN POSSIBLE THROUGH THE NEXT SEVERAL DAYS AS A WEAK FRONTAL BOUNDARY SETS UP OVER THE SOUTHERN GREAT LAKES. THUNDERSTORMS ARE BEING AIDED BY VERY WARM AND HUMID AIRMASS CURRENTLY IN PLACE ACROSS THE REGION. HIGHS TODAY WILL BE IN THE UPPER 80S TO LOWER 90S WITH OVERNIGHT LOWS AROUND 70. && .UPDATE... ISSUED AT 1010 AM EDT WED JUN 18 2014 INTERESTING BUT COMPLICATED NR TERM THIS MORNING AS POTENT UPSTREAM MCV PIVOTS OUT OF SE MN. ATTENDANT BKN LINE OF CONVN FM SRN WI SWWD INTO ERN SHOWING SIGNS NOW OF FWD PROPAGATION INTO RAPIDLY GROWING INSTABILITY AXIS POSITIONED W-E ACRS THE SRN LAKES INVOF DECAYING CIRRUS SHIELD...AND NO DOUBT AUGMENTED W/POTENT 50KT MID LVL SPEED MAX. HWVR COMPLICATING FCTR IS OUTFLW BNDRY EXTENDING FM FAR NE IL ESE INTO NW OH THAT MAY WITH TIME INITIATE ADDNL CONVN AHD OF THE BOWING LINE MVG OUT OF SE WI. AT EITHER RATE IT WOULD APPEAR A MORE CONSIDERABLE RISK FOR SEVERE STORMS IS SHAPING UP FOR THIS AFTN. ZONE UPDATES WILL BE FORTHCOMING. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 422 AM EDT WED JUN 18 2014 ACTIVE WEATHER PATTERN CONTINUES FOR THE SOUTHERN GREAT LAKES AS SEVERAL CONVECTIVELY ENHANCED SHORTWAVES EJECT OUT OF WESTERN CONUS UPPER LOW AND TRAVEL ALONG QUASI-STATIONARY E-W FRONTAL BOUNDARY DRAPED THROUGH THE REGION. STRONG LLJ AHEAD OF THE MAIN TROUGH IS STILL MAINTAINING A CONTINUAL FEED OF VERY HIGH THETA-E AIR INTO THE MIDWEST AND OHIO VALLEY...SUPPORTING UNSTABLE CONDITIONS. SIMILAR TO THE PREVIOUS NIGHT...CONVECTION HAS FIRED UPSTREAM ON THE NOSE OF THE LLJ/MOISTURE CONVERGENCE AND HAS SLOWLY DRIFTED EASTWARD. THE DIFFERENCE IS THAT STORM CLUSTERS HAVE BEEN A LITTLE MORE DISCREET AND DISORGANIZED THUS FAR. UPSCALE GROWTH/ORGANIZATION LIKELY INHIBITED BY VERY STRONG CAPPING INVERSION NOTED ON 00Z KILX AND KDVN SOUNDINGS AS WELL AS A LACK OF ANY CLEAR SYNOPTIC SCALE SHORTWAVE/LINEAR FORCING. STORM CLUSTERS TO OUR NORTH AND NORTHWEST HAVE GRADUALLY FILLED IN/CONGLOMERATED DURING THE PAST FEW HOURS THOUGH...THANKS TO NOCTURNAL STRENGTHENING OF LLJ AND ASSOCIATED INCREASE IN LOW LEVEL MOISTURE AVAILABLE UPSTREAM. QUESTION IS HOW WILL THIS ACTIVITY EVOLVE THROUGH THE MORNING AND INTO THE AFTERNOON. LATEST SURFACE OBS ACTUALLY SHOW A FAIRLY PRONOUNCED TEMP AND MOISTURE GRADIENT JUST NORTH OF OUR CWA. ISENTROPIC ASCENT ALONG AND NORTH OF THIS SURFACE BOUNDARY IS DRIVING MUCH OF THE CURRENT CONVECTION WHILE ATMOSPHERE REMAINS CAPPED TO THE SOUTH. NOTHING TO FORCE THIS FRONT SOUTHWARD THROUGH THE MORNING WITH CONTINUAL SOUTHWEST FLOW/WAA AND NO ORGANIZED COLD POOLS/OUTFLOW BOUNDARIES AS OF YET. THEREFORE EXPECT OUR CWA WILL REMAIN LARGELY DRY DURING THIS PERIOD. SITUATION MAY CHANGE BY THE AFTERNOON AND EVENING. 00Z MODELS SUGGEST THAT A SUBTLE WAVE ASSOCIATED WITH CONVECTION CURRENTLY OVER FAR NW IA AND SOUTHERN MN WILL PUSH ESE BY LATER TODAY. SIMULTANEOUS SOUTHWARD PUSH OF CANADIAN ANTICYCLONE MAY FORCE THE FRONTAL BOUNDARY SOUTHWARD A BIT...WITH THE HELP OF COLD LAKES AND OUTFLOW FROM MORNING THUNDERSTORMS. MODELS INDICATE THIS WILL LIKELY BE ENOUGH TO WEAKEN THE STRONG CAP IN PLACE ACROSS OUR CWA AND ALLOW STORMS TO DEVELOP AND/OR PROPAGATE INTO OUR AREA BY THE AFTERNOON AND EVENING. LATEST HRRR AND HI-RES WRF-NMM ARE GENERALLY IN LINE WITH THIS IDEA. IF THE CAP DOES BREAK AS EXPECTED THEN SEVERE WEATHER WILL BE QUITE POSSIBLE. MODIFIED FORECAST SOUNDINGS INDICATE AROUND 3000 J/KG OF SBCAPE ACROSS THE AREA BY THE AFTERNOON. 0-6KM BULK SHEAR IS NOT AS HIGH SOUTH OF I-80 BUT SUFFICIENT FOR ORGANIZED LINE SEGMENTS/BOWS GIVEN LARGELY UNIDIRECTIONAL WIND FIELDS. LARGE HAIL AND STRONG WINDS WOULD BE THE PRIMARY THREATS WITH ANY STORMS THAT DO DEVELOP. THREAT FOR TORNADOES IS MUCH LOWER GIVEN LIMITED LOW LEVEL DIRECTIONAL SHEAR BUT CAN`T RULE IT OUT ENTIRELY. ALL OF THIS IS OF COURSE CONDITIONAL ON MORNING CONVECTIVE TRENDS AND GETTING ENOUGH SYNOPTIC SCALE ASCENT/COOLING TO ERODE THE STOUT 850-750MB INVERSION. CONFIDENCE IN THIS SCENARIO IS NOT HIGH ENOUGH TO SUPPORT LIKELY POPS JUST YET AND WILL HOLD WITH HIGH END CHANCES. THESE CHANCES WILL CONTINUE INTO THE OVERNIGHT PERIOD AS LLJ STRENGTHENS ONCE AGAIN AND POSSIBLY SUPPORTS PERSISTENT CONVECTION FOR OUR CWA IF SOUTHWARD PUSH OF FRONTAL BOUNDARY MATERIALIZES. && .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 422 AM EDT WED JUN 18 2014 LITTLE SUBSTANTIVE CHANGE TO LONG TERM PERIOD. EXPECT PRODIGIOUS CONVECTION SPAWNING ALONG/DOWNSTREAM OF INTENSE INTERMOUNTAIN MID TROPOSPHERIC VORTEX TO CONTINUE INTO THIS WEEKEND. ACTIVE PATTERN WITH CONTINUATION OF CONVECTIVE INDUCED MESOVORTICIES AFFORDING TO INITIATE/RENEW TSRA ALONG/NORTH OF SURFACE FRONTAL BOUNDARY THAT PRESENTLY EXTENDS FROM NORTHERN NE TO CENTRAL WI THEN SOUTHEASTWARD THROUGH THE SOUTHERN GREAT LAKES REGION. WHILE STRONGEST INSTABILITY AND MORE SIGNIFICANT FOCUS FOR INITIATION REMAINS UPSTREAM OF CWA ON THU...HAVE CONTD CHC POP MENTION/HIGHEST IN SOUTHWEST CWA AS NORTHERN ONTARIO ANTICYCLONE SHIFTS SEWD AND ASSERTS RIDGING SOUTHWARD THROUGH LAKE HURON INTO NWRN OH...SHUNTING CONVECTIVE MAINTENANCE FARTHER SOUTH AS IT PROGRESSES DOWNSTREAM. FRIDAY PRESENTS EVEN HIGHER POTENTIAL FOR MORE WIDESPREAD CONVECTION AS LOBE OF SIGNIFICANT 30-50M/12 HR MID LEVEL HEIGHT FALLS PEELS THROUGH WESTERN GREAT LAKES AS PRIMARY UPSTREAM VORTEX BIFURCATES DOWNSTREAM RIDGE TO BECOME REXED ACROSS SOUTHERN MANITOBA. MID 80S/NEAR 70 SURFACE CONDITIONS YIELD MODERATE INSTABILITY 2500-3500 J/KG SBCAPE AND MODEST DEEP LAYER SHEAR. DIFFERENTIATED FRIDAY WITH LIKELY POPS SANS TIMING GIVEN BETTER SIGNALS AMID RICH THETA-E REGIME FIRMLY IN PLACE. THEREAFTER INCREASING MODEL DIVERGENCE NOTED WITH DEVOLUTION OF REXED SYSTEM WITH ECMWF/GEM MAINTAINING ORPHANED TROFFING ACROSS NORTHERN GREAT LAKES INTO NORTHERN PLAINS INTO NEXT WEEK AND GFS ESPECIALLY BTWN ECMWF AND GEM VS GFS RELEASE DOWNSTREAM THROUGH THE LOWER GREAT LAKES DYS5/6. POSSIBLE LULL SATURDAY THOUGH HIGHLY CONTINGENT ON FRIDAY CONVECTION LEADING TO SUBSTANTIAL OVERTURNING AND FAR SOUTHWARD BOUNDARY SHUNT. AT THIS TIME LOW CHANCE MENTION REMAINS GIVEN HIGH CONDITIONALITY. TREND DRY MONDAY NIGHT/TUESDAY AS DEEPER NORTH/NORTHEAST FLOW PER NORTHERN GREAT && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 140 PM EDT WED JUN 18 2014 SHALLOW/BRIEF MVFR CIGS ASSOCD/W TAIL END OF DECAYING CONV REMNANTS ACRS NW IN WILL MIX OUT QUICKLY INTO THIS AFTN. LTL SIGN YET OF WHERE/WHEN RENEWED CONV DVLPMNT WILL OCCUR AND AS SUCH WILL SIT TIGHT W/IMPLIED DRY TAF FCST THROUGH THE OVERNIGHT. MOST LIKELY SCENARIO IS FOR NEW CONVN TO INITIATE FM ERN IA EWD THROUGH NRN IL THIS EVENING AS LLJ KICKS UP AND THEN GROW UPSCALE INTO A FWD PROPAGATING MCS AS IT SPREADS EWD THROUGH THE SRN LAKES OVERNIGHT. OTRWS GUSTY SWRLY GRADIENT WINDS WILL SUBSIDE BY SUNSET. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ UPDATE...T SYNOPSIS...AGD SHORT TERM...AGD LONG TERM...MURPHY AVIATION...T VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.NORTHERNIN.GOV WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
355 PM CDT Wed Jun 18 2014 ...Updated for long term discussion... .SHORT TERM...(This evening through Thursday) ISSUED AT 251 PM CDT WED JUN 18 2014 A minor upper level trough is currently moving through western Kansas, with the stronger dynamics centered off to the north of our CWA. There is a cold front in the vicinity from Hays to north of Syracuse in Hamilton County as of 20z. A dry-line has formed and was from approximately Liberal to Garden City to Hill City at 20z. There was a lower level wave which moved up from the Texas Panhandle earlier this afternoon, which shoved the dry-line northeastward into the cold front, causing the cold front to bow northward in the Ness City/Hays area. This dry-line intrusion into the cold front also slowed the progress of the front to the southeast. A fairly good amount of mid to high level clouds covered most of the CWA at 20z, and a single storm formed near Scott City between 19Z and 20Z. The short term models of the RUC, HRRR and ARW all backed off on a solid line of storms forming along the dry-line this afternoon, but rather a patchy line of storms. There will still probably be a few isolated severe storms with quarter size hail, but do not think the severe storms will be widespread or very big hail (quarters). Will monitor SPC for a Watch. Overnight, the precipitation band from this afternoon should move east, with another surface low moving up from Oklahoma into the P28 area. The aforementioned front will progress southeast through our CWA and be near a Pratt to Coldwater line by 12Z in the morning. Therefore, with greater moisture available in the southeast zones, will increase Pops there toward 12Z, and then spread the Pops back to the northwest during the day Thursday. SPC`s Day2 outlook has about our southeast 1/3rd of the CWA in a slight risk. We will be cooler in the afternoon, with the cold front south of us. Have to agree with SPC`s assessment though, with the NAM model showing 3700 J/Kg of MuCape in our eastern zones, and 24 to 27Kts of bulk shear in that same zone Tuesday at 21Z. There will likely be some more severe storms, again with Quarters to a little larger hail. The TOR threat looks minimal, but some 60kt winds could easily mix down. As for Max/Min temperatures, I did not change anything. Lows tonight will be elevated in the 60F (NW) to 72F (SE) range. On Thursday, it will be cooler with maximum temperatures ranging from the mid 80s north of I-70 and upper 80s down south along the Oklahoma border. .LONG TERM...(Thursday night through Wednesday) ISSUED AT 346 PM CDT WED JUN 18 2014 The mid to upper level flow will become zonal by later this week and into the weekend. This will allow for lee troughing and a dryline situated across far western Kansas. Afternoon and early nighttime thunderstorms cannot be ruled out. But in the absence of upslope flow this far south, and with the lack of low level baroclinicity and a well defined upper level jet, organized thunderstorm activity will probably stay farther north through Saturday. High temperatures will be in the lower 90s through Saturday with lows mainly in the 60s. Thunderstorm chances are higher by late Sunday as a weak shortwave trough embedded in zonal flow traverses western Kansas. Organized thunderstorm activity is possible into Monday with this feature, along with cooler temperatures by Monday. Thunderstorm chances may diminish by late Monday and Tuesday as weak surface high pressure builds into western Kansas. However, by late Tuesday and into mid to late next week, there will be more opportunities for thunderstorms as westerly to northwesterly mid to high level flow persists, along with weak capping and plentiful low level moisture. High temperatures will be held down by cloud cover and convective debris. && .AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon) ISSUED AT 1159 AM CDT WED JUN 18 2014 basically, conditions will be VFR through this evening and into the overnight hours. A line of strong storms is expected to develop around 21-22z from west of KHYS south to near KDDC to just east of KLBL and points southward. Cigs will be elevated, at approximately bkn050cb, and vsbys should remain good. If a thunderstorm develops right over a TAF site, such as KDDC, vsby could go down for a short period. The main hazard with these storms this afternoon and evening will be hail to the size of quarters. There is also a chance for storms overnight, mainly in the KHYS and KDDC TAF sites. && .PRELIMINARY POINT TEMPS/POPS... DDC 67 87 63 91 / 20 30 30 20 GCK 65 86 62 92 / 20 10 10 20 EHA 63 87 63 91 / 20 10 10 20 LBL 67 89 64 92 / 20 20 20 20 HYS 68 86 62 91 / 20 20 30 20 P28 72 89 67 91 / 30 50 60 20 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Burke LONG TERM...Finch AVIATION...Burke
AREA FORECAST DISCUSSION
NWS WICHITA KS
319 PM CDT WED JUN 18 2014 .SYNOPSIS... ISSUED AT 317 PM CDT WED JUN 18 2014 UPPER LEVEL DATA ANALYSIS ENDING AT 19Z SHOWS A CLOSED LOW AT 500 MB OVER SOUTHWEST MONTANA. SOUTHWESTERLY FLOW CONTINUES ACROSS THE REGION AS A RESULT OF THIS LOW. THIS LOW CONTINUES TO MOVE SLOWLY NORTHEASTWARD. SATELLITE DATA LOOP ENDING AT 1915Z SHOWS AN AREA OF ACCAS THAT HAS EXTENDED FROM THE TEXAS PANHANDLE INTO CENTRAL KANSAS. THIS HAS BEEN PRESENT FOR SEVERAL HOURS AND OUTLINES THE AREA OF FAVORED CONVECTIVE INITIATION THIS AFTERNOON. AT THE SURFACE...LOW PRESSURE WAS CENTERED OVER SOUTHCENTAL SOUTH DAKOTA. A COLD FRONT EXTENDS FROM THIS LOW DOWN TO NEAR KODX-KTQK-KLIC. A DRYLINE EXTENDS FROM JUST WEST OF KGCK...SOUTH TO JUST WEST OF KLBL INTO THE OKLAHOMA AND TEXAS PANHANDLE. CONVECTIVE DEVELOPMENT HAS INITIATED ACROSS WEST TEXAS ALONG THE AFOREMENTIONED FAVORED AREA. THIS IS PRETTY CLOSE TO WHERE THE 17Z HRRR RUN HAS SHOWN IT. MAIN FORECAST CHALLENGE REMAINS CONVECTION. COOK && .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 317 PM CDT WED JUN 18 2014 THE TREND OF THE HRRR RUNS FOR CONVECTION THIS EVENING CONTINUES TO SHOW MORE RAINFALL FOR A GOOD PORTION OF THE FORECAST AREA. THIS IS A DIVERGENCE TO THE OTHER NWP...BUT GIVEN ITS ACCURACY AND PERFORMANCE...WILL MAKE ADJUSTMENTS TO THE FORECAST FOR TONIGHT. AS FAR AS SEVERE GOES...SHEAR/BUOYANCY COMBINATIONS SUGGEST POTENTIAL FOR ORGANIZED CONVECTION ACROSS WESTERN KANSAS. AS ONE MOVES EAST...DEEP LAYER SHEAR FALLS BELOW 20 KNOTS BEFORE YOU REACH INTERSTATE 135. THIS SHOULD PRECLUDE SEVERE CONVECTION EAST OF INTERSTATE 135. THE AFOREMENTIONED COLD FRONT WILL MOVE SOUTH INTO THE FORECAST AREA THURSDAY. THIS WILL BE THE FOCUS FOR CONVECTION THURSDAY AFTERNOON. SHEAR/BUOYANCY COMBINATIONS AGAIN LOOK FAVORABLE...THOUGH ON THE LOWER END OF THAT FAVORABILITY FOR ORGANIZED CONVECTION FOR SEVERE WEATHER. THIS FAVORABILITY WILL REMAIN IN THE VICINITY OF THE FRONT. IF STORMS STRAY FROM OR ORGANIZE AND MOVE AWAY FROM THE FRONT AND OUTRUN THE FAVORABLE DEEP LAYER SHEAR...THEY SHOULD WEAKEN. COOK .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 317 PM CDT WED JUN 18 2014 INTO THE WEEKEND...THE QUASISTATIONARY FRONT REMAINS AROUND THE REGION. NWP IS IN SOME DISARRAY WITH THE POSITION OF THE BOUNDARY...AFFECTED BY OUTFLOWS AND COLD POOLS. CONFIDENCE IN CONVECTION LOCATION IS QUITE LOW. THAT SAID...CONFIDENCE IS HIGH THAT THE FRONT REMAINS IN CLOSE ENOUGH PROXIMITY TO THE FORECAST AREA INTO THE MIDDLE OF NEXT WEEK...WITH FAVORABLE CONDITIONS FOR LATE AFTERNOON AND NOCTURNAL CONVECTION. SEVERE CONDITIONS WILL BE FAVORABLE NEAR THE STALLED FRONT...WHICH SHEAR/BUOYANCY COMBINATIONS ARE MOST FAVORABLE. COOK && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 1217 PM CDT WED JUN 18 2014 VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD. VISIBLE SATELLITE DETECTING SOME MID-LEVEL MOISTURE ADVECTING INTO SOUTH CENTRAL KANSAS...WITH BASES IN THE 120-150K RANGE. DIURNAL MIXING ALSO PRODUCING SOME CUMULUS WITH BASES 2-3K. OVERALL...MOISTURE IS LIMITED. SURFACE FRONTAL BOUNDARY REMAINS DRAPED ACROSS NORTHWEST KANSAS. CONVERGENCE ALONG THE FRONTAL BOUNDARY ONLY MODEST...WHICH COMBINED WITH LIMITED MOISTURE PUTS INTO QUESTION CONVECTIVE INITIATION LOCATION AND TIMING. WEAK DISTURBANCE MOVING NORTHEAST OUT OF NEW MEXICO COULD HELP INCREASE CONVERGENCE AND LIFT ALONG THE THE FRONT AND COOL MID-LEVEL TEMPERATURES JUST ENOUGH TO ALLOW ISOLATED STORMS TO FIRE. WILL FOLLOW PREVIOUS FORECAST TREND OF ONLY INCLUDING VCTS AT KRSL...BUT DECIDED TO BACK-OFF INITIATION TIME UNTIL AFTER 00 UTC. PASSAGE OF UPPER WAVE WILL DECREASE CHANCES OF STORMS AFTER 06 UTC. SOME SIGNAL THAT SCATTERED LOW VFR OR HIGH-END MVFR CIGS COULD ADVECT INTO SOUTH CENTRAL AND SOUTHEAST KANSAS BETWEEN 11-12 UTC...BUT NOT CONFIDENT ENOUGH TO INTRODUCE CEILINGS BASED ON DIFFERENCE IN OPERATIONAL MODELS AND CORROBORATION WITH SREF/NARRE-TL. SF && .PRELIMINARY POINT TEMPS/POPS... WICHITA-KICT 73 90 70 90 / 20 50 70 30 HUTCHINSON 73 90 69 91 / 30 50 70 20 NEWTON 72 88 69 90 / 20 50 70 20 ELDORADO 72 86 68 88 / 20 60 70 30 WINFIELD-KWLD 73 88 70 90 / 20 50 60 30 RUSSELL 70 89 66 92 / 50 40 40 20 GREAT BEND 70 89 67 92 / 50 40 50 20 SALINA 73 90 68 92 / 40 50 60 20 MCPHERSON 72 89 68 91 / 30 50 70 20 COFFEYVILLE 74 85 70 88 / 20 50 50 30 CHANUTE 73 85 69 88 / 30 50 50 30 IOLA 73 85 69 88 / 30 50 50 30 PARSONS-KPPF 73 85 70 88 / 30 50 50 30 && .ICT WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
255 PM CDT Wed Jun 18 2014 ...Updated for the short term discussion... .SHORT TERM...(This evening through Thursday) ISSUED AT 251 PM CDT WED JUN 18 2014 A minor upper level trough is currently moving through western Kansas, with the stronger dynamics centered off to the north of our CWA. There is a cold front in the vicinity from Hays to north of Syracuse in Hamilton County as of 20z. A dry-line has formed and was from approximately Liberal to Garden City to Hill City at 20z. There was a lower level wave which moved up from the Texas Panhandle earlier this afternoon, which shoved the dry-line northeastward into the cold front, causing the cold front to bow northward in the Ness City/Hays area. This dry-line intrusion into the cold front also slowed the progress of the front to the southeast. A fairly good amount of mid to high level clouds covered most of the CWA at 20z, and a single storm formed near Scott City between 19Z and 20Z. The short term models of the RUC, HRRR and ARW all backed off on a solid line of storms forming along the dry-line this afternoon, but rather a patchy line of storms. There will still probably be a few isolated severe storms with quarter size hail, but do not think the severe storms will be widespread or very big hail (quarters). Will monitor SPC for a Watch. Overnight, the precipitation band from this afternoon should move east, with another surface low moving up from Oklahoma into the P28 area. The aforementioned front will progress southeast through our CWA and be near a Pratt to Coldwater line by 12Z in the morning. Therefore, with greater moisture available in the southeast zones, will increase Pops there toward 12Z, and then spread the Pops back to the northwest during the day Thursday. SPC`s Day2 outlook has about our southeast 1/3rd of the CWA in a slight risk. We will be cooler in the afternoon, with the cold front south of us. Have to agree with SPC`s assessment though, with the NAM model showing 3700 J/Kg of MuCape in our eastern zones, and 24 to 27Kts of bulk shear in that same zone Tuesday at 21Z. There will likely be some more severe storms, again with Quarters to a little larger hail. The TOR threat looks minimal, but some 60kt winds could easily mix down. As for Max/Min temperatures, I did not change anything. Lows tonight will be elevated in the 60F (NW) to 72F (SE) range. On Thursday, it will be cooler with maximum temperatures ranging from the mid 80s north of I-70 and upper 80s down south along the Oklahoma border. .LONG TERM...(Thursday through Tuesday) ISSUED AT 228 AM CDT WED JUN 18 2014 Medium range models indicate a negatively tilted upper level trough of low pressure lifting northeast across the Northern Plains Thursday setting up precip chances from the Upper Midwest southwest into eastern and portions of central Kansas along an attendant frontal boundary. By Thursday afternoon, the GFS/ECMWF show a narrow +70kt upper level jet lifting northeast across central and western Kansas while deep low/mid level moisture pools across south central Kansas ahead of the near stationary frontal boundary. As lapse rates steepen and capping weakens through late Thursday afternoon, thunderstorms are very likely to develop in the vicinity of the frontal boundary, affecting central and possibly eastern portions of southwest Kansas. The focus for thunderstorms will shift northward overnight as the frontal boundary, and an associated surface low in southwest Kansas, begins to lift back to the north as a warm front. The potential for severe storms exists with favorable vertical shear profiles, CAPE values in excess of 3000 J/KG, and very steep lapse rates along and south of the frontal boundary. Large hail and damaging winds will be the primary threat with an isolated tornado not out of the question. The flow aloft is then expected to become weaker while becoming more westerly across the Western High Plains through the weekend. Even with ample low/mid level moisture present, this will limit the chances for more significant rainfall through the weekend. Slightly cooler temperatures are expected Thursday as a cold front pushes through western Kansas before stalling out in the vicinity of south central Kansas near the Oklahoma border. Cooler air will filter southward into west central and portions of southwest Kansas limiting highs only up into the 80s(F) Thursday afternoon. Near 90F is still a possibility in south central Kansas depending where the frontal boundary eventually stalls out. Highs back up into the 90s(F) are then likely Friday through the weekend as a low level southerly flow redevelops across western Kansas and persists through at least Sunday. && .AVIATION...(For the 18Z TAFS through 18Z Thursday afternoon) ISSUED AT 1159 AM CDT WED JUN 18 2014 basically, conditions will be VFR through this evening and into the overnight hours. A line of strong storms is expected to develop around 21-22z from west of KHYS south to near KDDC to just east of KLBL and points southward. Cigs will be elevated, at approximately bkn050cb, and vsbys should remain good. If a thunderstorm develops right over a TAF site, such as KDDC, vsby could go down for a short period. The main hazard with these storms this afternoon and evening will be hail to the size of quarters. There is also a chance for storms overnight, mainly in the KHYS and KDDC TAF sites. && .PRELIMINARY POINT TEMPS/POPS... DDC 67 87 63 91 / 20 30 30 20 GCK 65 86 62 92 / 20 10 10 20 EHA 63 87 63 91 / 20 10 10 20 LBL 67 89 64 92 / 20 20 20 20 HYS 68 86 62 91 / 30 20 30 20 P28 72 89 67 91 / 30 50 60 20 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Burke LONG TERM...JJohnson AVIATION...Burke
AREA FORECAST DISCUSSION
NWS JACKSON KY
255 PM EDT WED JUN 18 2014 .UPDATE... ISSUED AT 145 PM EDT WED JUN 18 2014 A FEW STRONGER STORMS DEVELOPED QUICKLY OVER THE FAR EASTERN PART OF KENTUCKY EARLIER IN THE AFTERNOON. THESE ARE NOW WANING WITH MORE ISOLATED SHOWERS AND STRAY STORMS...BUILT ON THE ORIGINAL STORMS/S OUTFLOW BOUNDARIES...FOUND ACROSS THE REST OF THE CWA AND INTO CENTRAL KENTUCKY. HAVE UPDATED THE GRIDS TO REFLECT THIS... HITTING THE FAR EAST WITH THE HIGHEST POPS AND SKY COVER. OTHERWISE...MADE SOME TWEAKS TO TEMPS TO REFLECT THE LATEST OBS AND TRENDS...CAPTURING THE...OH SO TEMPORARY...COOLING EFFECT OF THE CONVECTION IN THE EAST. THESE HAVE BEEN SENT TO THE NDFD AND WEB SERVERS. UPDATE ISSUED AT 1035 AM EDT WED JUN 18 2014 14Z SFC ANALYSIS SHOWS HIGH PRESSURE OFF TO THE SOUTHEAST OF KENTUCKY WITH A PERSISTENT AND BROAD AREA OF LOW PRESSURE OVER THE PLAINS. FROM THIS LOW...A QUASI-STATIONARY BOUNDARY EXISTS ACROSS THE SOUTHERN TIER OF THE GREAT LAKES SERVING AS A GUIDE PATH FOR PERIODIC CLUSTERS OF SEMI-ORGANIZED STORMS. THAT SHOULD BE THE CASE TODAY...AS WELL. CLOSER TO HOME...THE HIGH PRESSURE SOUTH OF THE FRONT IS FAIRLY WEAK...ALONG WITH THE RIDGE ALOFT. THIS HAS HAD PROBLEMS KEEPING THE AREA BLEMISH FREE THROUGH PEAK HEATING THE PAST COUPLE OF DAYS AND TODAY SHOULD BE NO DIFFERENT. IN FACT...DUE TO THE CONTINUED FLOW OF WARM...MOIST...AND UNSTABLE AIR INTO THIS PART OF THE STATE DO EXPECT TO SEE A LITTLE BIT MORE COVERAGE OF ANY ACTIVITY LATE THIS AFTERNOON. THE HRRR SUPPORTS THIS...ALBEIT A BIT GUNG-HO WHEN COMPARED TO PERSISTENCE AND THE NAM12...AND AS OTHER COARSER RESOLUTION MODELS. NEVERTHELESS...THE CONDITIONS APPEAR TO WARRANT THE INTRODUCTION OF ISOLATED POPS FOR THE LATTER PART OF THE AFTERNOON. HAVE ADDED THESE TO THE GRIDS AND UPDATED THE ZONES/HWO TO CONVEY THE CONCERN. ALSO FINE TUNED TEMPERATURES...DEWPOINTS...AND SKY COVER THROUGH THE NEXT SEVERAL HOURS PER THE LATEST OBS... TRENDS...AND GUIDANCE. THESE HAVE BEEN SENT TO THE NDFD AND WEB SERVERS. && .SHORT TERM...(TODAY THROUGH THURSDAY) ISSUED AT 229 AM EDT WED JUN 18 2014 ANOTHER HOT AND HUMID DAY IS IN STORE FOR EASTERN KENTUCKY. THE HIGH PRESSURE REMAINS FIRMLY IN CONTROL. THE QUASI-STATIONARY FRONT DRAPED ACROSS THE GREAT LAKES WILL BEGIN TO MOVE A LITTLE TO THE SOUTH. THIS WILL MOVE THE CONVECTION TO THE SOUTH AS WELL. THE BIG QUESTION IS THE TIMING OF THIS FRONT AND WHEN THE PRECIPITATION WILL FINALLY BE ABLE TO MOVE INTO EASTERN KENTUCKY. THE MODELS HAVE CONSISTENTLY BEEN TOO QUICK TO BREAK DOWN THE RIDGING AND ALLOW THE SYSTEM TO MOVE SOUTH. THIS BEING SAID...THE LEADING EDGE MAY BE MOVING INTO THE NORTHERN PORTION OF THE AREA TONIGHT WITH SOME ISOLATED TO SCATTERED THUNDERSTORMS AND THEN ACROSS ALL OF EASTERN KENTUCKY ON THURSDAY. STILL HAVE SOME CONCERN THAT ANY THUNDERSTORMS THAT DEVELOP COULD BE STRONG DUE TO THE INSTABILITY AND THE POTENTIAL ENERGY CREATED BY A COMBINATION OF THE INSTABILITY AND MOISTURE. THE LIFTED INDEX THIS EVENING IS FORECAST TO BE AROUND -6 WITH 3000 TO 4000 JOULES OF CONVECTIVE AVAILABLE POTENTIAL ENERGY (CAPE). TONIGHT...THERE WILL BE A WEAK SHORT WAVE MOVING ACROSS THE AREA. THIS MAY PROVIDE THE NECESSARY TRIGGER TO GET THE CONVECTION GOING. ON THURSDAY...THE MODELS ARE SHOWING A LOT MORE MOISTURE ALOFT MOVING INTO THE AREA WITH PRECIPITABLE WATER VALUES AROUND 1.6 INCHES. THIS COULD ALLOW FOR SOME SOAKERS...ESPECIALLY FOR ANY CELLS THAT TRAIN. THE O-6 KM WINDS ARE ONLY FORECAST TO BE AROUND 11 MPH. WITH THE SLOW MOVING CELLS...THE STORMS WILL BE ABLE TO DUMP MORE WATER AND THIS COULD CAUSE SOME OF THE DITCHES AND LOW WATER CROSSING TO BE RUNNING FULL. EXPECT ANOTHER UNCOMFORTABLE DAY WITH NEAR RECORD TEMPERATURES. THE REPEATED HOT DAYS AND FAIRLY WARM EVENINGS...COULD START TO STRESS THE ELDERLY AND THE INFIRM AS WELL AS LIVESTOCK AND PETS. SOME EXTRA CARE SHOULD BE TAKEN TO PROVIDE ADEQUATE HYDRATION AND COOLING. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 255 PM EDT WED JUN 18 2014 THE UPPER LEVEL RIDGING WHICH HAS BROUGHT US THE RECENT HOT WEATHER WILL BE SHIFTING OFF TO THE SOUTHWEST DURING THE LONG TERM PERIOD OF THE FORECAST. DESPITE THIS EXPECT TEMPERATURES TO REMAIN ABOVE NORMAL. HOWEVER THE CHANCES FOR PRECIPITATION WILL BE GREATER THAN THEY HAVE BEEN RECENTLY AS WEAK DISTURBANCES MOVE ACROSS THE REGION FROM THE NORTHWEST. A WEAK COLD FRONT WILL PASS THROUGH THE AREA EARLY SATURDAY WITH THE BEST CHANCE OF RAIN FRIDAY INTO EARLY SATURDAY. BOTH THE GFS AND NAM FORECAST PRECIPITABLE WATER 1.80 TO OVER 1.95 INCHES AT 00Z ON SATURDAY...OR AROUND OR POSSIBLY GREATER THAN THE 99TH PERCENTILE. THIS...COMBINED WITH STORM MOTION FORECAST TO BE 5 TO 15 KNOTS COULD LEAD TO LOCALLY HEAVY RAIN FRIDAY INTO FRIDAY NIGHT...AND ISOLATED FLOODING. HAVE MENTIONED THIS POSSIBILITY IN THE LATEST HAZARDOUS WEATHER OUTLOOK. THE FRONT SHOULD GET FAR ENOUGH SOUTH THAT RAIN CHANCES WILL DECREASE OVER THE WEEKEND BUT STILL NEED TO BE MENTIONED IN THE FORECAST. WHILE THERE IS DECENT MODEL AGREEMENT TO START THE LONG TERM PERIOD THERE ARE CONSIDERABLE DIFFERENCES NEXT WEEK...BUT NOT ANY THAT CHANGE THE OVERALL FORECAST OF DAILY SHOWER AND THUNDERSTORM CHANCES. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 210 PM EDT WED JUN 18 2014 STILL SOME UNCERTAINTY WITH THE EVOLUTION OF STORMS THROUGH THE REST OF THE AFTERNOON AND INTO THE EVENING...THOUGH THEY SHOULD BE FAR FLUNG ENOUGH TO LIMIT MENTION TO JUST VCTS IN THE TAFS. LATER TONIGHT...A BETTER THREAT OF CONVECTION LIKELY DEVELOPS OVER THE NORTHERN PARTS OF THE CWA...POTENTIALLY IMPACTING THE SOUTH WITH TIME INTO THURSDAY MORNING. HAVE GONE WITH A VCTS RENEWAL TOWARDS 12Z AT ALL SITES CONTINUING THROUGH THE MORNING THURSDAY. FOR THE JKL AND SJS LOCATIONS DID GO WITH A TEMPO STRADDLING 12Z FOR BETTER CHANCES OF THUNDERSTORMS AND AVN WX IMPACTS...PREDOMINANTLY IN THE MVFR RANGE. OUTSIDE OF ANY THUNDERSTORMS WINDS WILL BE LIGHT AND VARIABLE AT NIGHT AND FROM THE SOUTHWEST AT 5 TO 10 KTS DURING THE DAY. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GREIF SHORT TERM...JJ LONG TERM...SBH AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
210 PM EDT WED JUN 18 2014 .UPDATE... ISSUED AT 145 PM EDT WED JUN 18 2014 A FEW STRONGER STORMS DEVELOPED QUICKLY OVER THE FAR EASTERN PART OF KENTUCKY EARLIER IN THE AFTERNOON. THESE ARE NOW WANING WITH MORE ISOLATED SHOWERS AND STRAY STORMS...BUILT ON THE ORIGINAL STORMS/S OUTFLOW BOUNDARIES...FOUND ACROSS THE REST OF THE CWA AND INTO CENTRAL KENTUCKY. HAVE UPDATED THE GRIDS TO REFLECT THIS... HITTING THE FAR EAST WITH THE HIGHEST POPS AND SKY COVER. OTHERWISE...MADE SOME TWEAKS TO TEMPS TO REFLECT THE LATEST OBS AND TRENDS...CAPTURING THE...OH SO TEMPORARY...COOLING EFFECT OF THE CONVECTION IN THE EAST. THESE HAVE BEEN SENT TO THE NDFD AND WEB SERVERS. UPDATE ISSUED AT 1035 AM EDT WED JUN 18 2014 14Z SFC ANALYSIS SHOWS HIGH PRESSURE OFF TO THE SOUTHEAST OF KENTUCKY WITH A PERSISTENT AND BROAD AREA OF LOW PRESSURE OVER THE PLAINS. FROM THIS LOW...A QUASI-STATIONARY BOUNDARY EXISTS ACROSS THE SOUTHERN TIER OF THE GREAT LAKES SERVING AS A GUIDE PATH FOR PERIODIC CLUSTERS OF SEMI-ORGANIZED STORMS. THAT SHOULD BE THE CASE TODAY...AS WELL. CLOSER TO HOME...THE HIGH PRESSURE SOUTH OF THE FRONT IS FAIRLY WEAK...ALONG WITH THE RIDGE ALOFT. THIS HAS HAD PROBLEMS KEEPING THE AREA BLEMISH FREE THROUGH PEAK HEATING THE PAST COUPLE OF DAYS AND TODAY SHOULD BE NO DIFFERENT. IN FACT...DUE TO THE CONTINUED FLOW OF WARM...MOIST...AND UNSTABLE AIR INTO THIS PART OF THE STATE DO EXPECT TO SEE A LITTLE BIT MORE COVERAGE OF ANY ACTIVITY LATE THIS AFTERNOON. THE HRRR SUPPORTS THIS...ALBEIT A BIT GUNG-HO WHEN COMPARED TO PERSISTENCE AND THE NAM12...AND AS OTHER COARSER RESOLUTION MODELS. NEVERTHELESS...THE CONDITIONS APPEAR TO WARRANT THE INTRODUCTION OF ISOLATED POPS FOR THE LATTER PART OF THE AFTERNOON. HAVE ADDED THESE TO THE GRIDS AND UPDATED THE ZONES/HWO TO CONVEY THE CONCERN. ALSO FINE TUNED TEMPERATURES...DEWPOINTS...AND SKY COVER THROUGH THE NEXT SEVERAL HOURS PER THE LATEST OBS... TRENDS...AND GUIDANCE. THESE HAVE BEEN SENT TO THE NDFD AND WEB SERVERS. && .SHORT TERM...(TODAY THROUGH THURSDAY) ISSUED AT 229 AM EDT WED JUN 18 2014 ANOTHER HOT AND HUMID DAY IS IN STORE FOR EASTERN KENTUCKY. THE HIGH PRESSURE REMAINS FIRMLY IN CONTROL. THE QUASI-STATIONARY FRONT DRAPED ACROSS THE GREAT LAKES WILL BEGIN TO MOVE A LITTLE TO THE SOUTH. THIS WILL MOVE THE CONVECTION TO THE SOUTH AS WELL. THE BIG QUESTION IS THE TIMING OF THIS FRONT AND WHEN THE PRECIPITATION WILL FINALLY BE ABLE TO MOVE INTO EASTERN KENTUCKY. THE MODELS HAVE CONSISTENTLY BEEN TOO QUICK TO BREAK DOWN THE RIDGING AND ALLOW THE SYSTEM TO MOVE SOUTH. THIS BEING SAID...THE LEADING EDGE MAY BE MOVING INTO THE NORTHERN PORTION OF THE AREA TONIGHT WITH SOME ISOLATED TO SCATTERED THUNDERSTORMS AND THEN ACROSS ALL OF EASTERN KENTUCKY ON THURSDAY. STILL HAVE SOME CONCERN THAT ANY THUNDERSTORMS THAT DEVELOP COULD BE STRONG DUE TO THE INSTABILITY AND THE POTENTIAL ENERGY CREATED BY A COMBINATION OF THE INSTABILITY AND MOISTURE. THE LIFTED INDEX THIS EVENING IS FORECAST TO BE AROUND -6 WITH 3000 TO 4000 JOULES OF CONVECTIVE AVAILABLE POTENTIAL ENERGY (CAPE). TONIGHT...THERE WILL BE A WEAK SHORT WAVE MOVING ACROSS THE AREA. THIS MAY PROVIDE THE NECESSARY TRIGGER TO GET THE CONVECTION GOING. ON THURSDAY...THE MODELS ARE SHOWING A LOT MORE MOISTURE ALOFT MOVING INTO THE AREA WITH PRECIPITABLE WATER VALUES AROUND 1.6 INCHES. THIS COULD ALLOW FOR SOME SOAKERS...ESPECIALLY FOR ANY CELLS THAT TRAIN. THE O-6 KM WINDS ARE ONLY FORECAST TO BE AROUND 11 MPH. WITH THE SLOW MOVING CELLS...THE STORMS WILL BE ABLE TO DUMP MORE WATER AND THIS COULD CAUSE SOME OF THE DITCHES AND LOW WATER CROSSING TO BE RUNNING FULL. EXPECT ANOTHER UNCOMFORTABLE DAY WITH NEAR RECORD TEMPERATURES. THE REPEATED HOT DAYS AND FAIRLY WARM EVENINGS...COULD START TO STRESS THE ELDERLY AND THE INFIRM AS WELL AS LIVESTOCK AND PETS. SOME EXTRA CARE SHOULD BE TAKEN TO PROVIDE ADEQUATE HYDRATION AND COOLING. .LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY) ISSUED AT 302 AM EDT WED JUN 18 2014 MORE OF THE SAME IN THE EXTENDED THIS GO ROUND. THE MODELS ARE STILL HAVING A VERY DIFFICULT TIME CONVERGING ON A COMMON SOLUTION AS FAR AS THE OVERALL LARGE SCALE WEATHER PATTERN AND THE TIMING OF WEATHER SYSTEM PASSAGE ACROSS THE CONUS FROM THURSDAY NIGHT ONWARD. WITH THAT BEING SAID...WENT WITH A SLIGHTLY MODIFIED VERSION OF THE STANDARD LONG TERM GRID POPULATION PROCEDURE...WITH THE DATA BEING BLENDED WITH WHAT I FELT WAS THE MORE REASONABLE GFS MODEL GUIDANCE. THERE WILL BE A CHANCE OF SHOWERS EACH DAY IN THE EXTENDED...WITH THE HIGHER RAIN CHANCES GENERALLY OCCURRING DURING THE AFTERNOON AND EVENING HOURS DURING PEAK HEATING. THIRTY TO FIFTY PERCENT PRECIPITATION PROBABILITIES WERE USED ACROSS THE BOARD TO REFLECT THIS. A COUPLE OF FRONTAL BOUNDARIES...AND FRONTAL WAVES MOVING ALONG THEM...WILL BE THE TRIGGERING MECHANISMS FOR SHOWERS AND STORMS. THE EXTENDED PERIOD WILL STILL BE QUITE WARM...WITH ABOVE NORMAL TEMPERATURES...BUT NOT NEARLY AS WARM AS IT HAS BEEN THE PAST COUPLE OF DAYS ACROSS EASTERN KENTUCKY. LOOK FOR HIGHS MOSTLY IN THE MID 80S...WITH SLIGHTLY COOLER VALUES TOWARD THE END OF THE PERIOD AS SHOWERS AND STORMS BECOME MORE WIDESPREAD AS A FRONTAL BOUNDARY MEANDERS ABOUT THE REGION. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 210 PM EDT WED JUN 18 2014 STILL SOME UNCERTAINTY WITH THE EVOLUTION OF STORMS THROUGH THE REST OF THE AFTERNOON AND INTO THE EVENING...THOUGH THEY SHOULD BE FAR FLUNG ENOUGH TO LIMIT MENTION TO JUST VCTS IN THE TAFS. LATER TONIGHT...A BETTER THREAT OF CONVECTION LIKELY DEVELOPS OVER THE NORTHERN PARTS OF THE CWA...POTENTIALLY IMPACTING THE SOUTH WITH TIME INTO THURSDAY MORNING. HAVE GONE WITH A VCTS RENEWAL TOWARDS 12Z AT ALL SITES CONTINUING THROUGH THE MORNING THURSDAY. FOR THE JKL AND SJS LOCATIONS DID GO WITH A TEMPO STRADDLING 12Z FOR BETTER CHANCES OF THUNDERSTORMS AND AVN WX IMPACTS...PREDOMINANTLY IN THE MVFR RANGE. OUTSIDE OF ANY THUNDERSTORMS WINDS WILL BE LIGHT AND VARIABLE AT NIGHT AND FROM THE SOUTHWEST AT 5 TO 10 KTS DURING THE DAY. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GREIF SHORT TERM...JJ LONG TERM...AR AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS GRAY ME
517 PM EDT WED JUN 18 2014 .SYNOPSIS... A WEAK SECONDARY COLD FRONT WILL MOVE THROUGH TONIGHT. HIGH PRESSURE WILL BUILD IN FROM THE NORTHWEST THURSDAY INTO THE UPCOMING WEEKEND. A COLD FRONT WILL BRING AN INCREASING CHANCE OF SHOWERS AND THUNDERSTORMS TUESDAY INTO WEDNESDAY. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... UPDATE... HAVE UPDATED THE GRIDS TO ACCOUNT FOR LINE OF SHOWERS MOVING THROUGH THE WESTERN MOUNTAINS OF MAINE EARLY THIS EVENING...AS WELL AS NORTHERN NH. THERE COULD BE AN ISOLATED THUNDERSTORM IN THIS AREAS OF CONVECTION AS WELL. AS THE SHOWERS HEAD SOUTHEAST...DOWNSLOPING WILL CAUSE THE MOISTURE TO DISSIPATE WITH TIME. THIS HAS BEEN HANDLED WELL BY LATEST HRRR PRODUCTS. ONLY A FEW TWEAKS TO THE REMAINDER OF THE GRIDDED PACKAGE EARLY THIS EVENING. PREV DISC... A WEAK SECONDARY COLD FRONT WILL MOVE THRU THE REGION THIS EVENING WITH HARDLY A NOTICE..OTHER THAN SOME CLDS AND MAYBE A SHWR IN THE MTNS. OTHER DOWNSLOPING AREAS WILL BECOME MOSTLY CLEAR TONIGHT AND THE GUSTY WINDS WILL QUICKLY SUBSIDE AROUND SS. USED THE SUPERBLEND GUID FOR TONIGHT. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/... THE NWLY FLOW ALOFT WILL CONTINUE ALLOWING A VERY DRY AND PLEASANT NWLY FLOW TO CONTINUE THURS AND THURS NIGHT. WINDS WILL NOT BE AS GUSTY DURING THE DAY BUT STILL A STEADY NWLY BREEZE AS CANADIAN SFC HIGH PRES SLOWLY BUILDS SEWD INTO THE REGION. ON THURS NIGHT HIGH PRES WILL SETTLE OVER THE AREA WITH CONTINUED PLEASANT CONDS. USED THE SUPERBLEND FOR TEMPS FCST. && .LONG TERM /FRIDAY THROUGH WEDNESDAY/... 500 MB BLOCKING TO OUR E WILL KEEP CLOSED LOW MEANDERING AROUND THE MARITIMES FRIDAY THRU THE WEEKEND. THIS WILL KEEP THE CWA MAINLY IN NW FLOW...WHICH SHOULD PROVIDE MAINLY SUNNY SKIES...AND TEMPERATURES RUNNING NEAR NORMAL ON HIGHS...BUT SLIGHTLY COOLER AT NIGHT. SO...ALL IN ALL...A PLEASANT WEEKEND. FRIDAY COULD SEE A BREEZY NW FLOW...WITH GUSTS OF 20-25 MPH...BUT WINDS SHOULD DIMINISH FOR SAT/SUN. THE FLOW ALOFT BECOMES A BIT MORE ZONAL BY MONDAY...WITH PERHAPS A HINT OF RIDGING...WHICH SHOULD WARM THINGS UP A BIT ON MONDAY. MODELS THEN SHOWING A 500 WAVE CROSSES JUST TO OUR N...WHICH COULD BRING A FRONT THROUGH THE REGION TUE OR WED...DEPENDING ON WHICH MODEL YOU LOOK AT...WHICH WILL BE OUR NEXT CHC OF SHRA/TSRA. && .AVIATION /21Z WEDNESDAY THROUGH MONDAY/... SHORT TERM /THROUGH THURSDAY/...VFR CONDS. LONG TERM...SOME NW WIND GUSTS OF 20-25 KT POSSIBLE ON FRI...OTHERWISE VFR FRI THRU MON. && .MARINE... SHORT TERM...SCA WINDS CONTINUE ATTM SO WILL CONTINUE THE SCA UNTIL 00Z. AFTER SS WINDS WILL QUICKLY BECOME LIGHT FROM THE NW. THE NW WINDS ON THU WILL ONCE INCREASE SOME BUT SHOULD STAY WELL BELOW SCA CRIT. WINDS WILL BECOME LIGHT ONCE AGAIN THU NIGHT. LONG TERM...THE WATERS WILL REMAIN BLO SCA LVLS FRIDAY THRU MONDAY...ALTHOUGH SOME NW GUSTS TO 20 KT WILL BE POSSIBLE ON FRI. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...NONE. NH...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR ANZ150- 152-154. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...NONE. NH...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR ANZ150- 152-154. && $$
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
329 PM EDT WED JUN 18 2014 .SYNOPSIS... HIGH PRESSURE WILL REMAIN ACROSS THE SOUTHEASTERN STATES THROUGH TONIGHT. A WEAK COLD FRONT WILL MOVE INTO THE REGION FROM THE NORTHWEST ON THURSDAY AND WILL STALL JUST SOUTH OF THE AREA FRIDAY INTO THE WEEKEND. ANOTHER WEAK COLD FRONT APPROACHES THE REGION NEXT WEEK. && .NEAR TERM /THROUGH THURSDAY/... AS OF 18Z...BOUNDARY OVER THE DC AREA IS FROM OVERNIGHT/MORNING ACTIVITY OVER PA. DEWPOINTS ARE AROUND 70F ALONG THIS BOUNDARY WITH UPR 60S BOTH NORTH (BALTIMORE) AND SOUTH (CHARLOTTESVILLE). WITH TEMPERATURES GENERALLY LOW TO MID 90S...THE HIGHEST HEAT INDICES ARE AROUND 100 DEGREES IN DC...WITH MID TO UPR 90S ELSEWHERE. ISOLATED SHOWER/THUNDERSTORM ACTIVITY WILL CONTINUE ALONG THIS FRONT AS INDICATED FROM THE LATEST FORECAST UPDATE. LACK OF SHEAR WILL MAKE FOR PULSE ACTIVITY. WILL NEED TO CONTINUE WATCHING THE MCS OVER IL/MI WHICH HAS A WEAKER RADAR MOSAIC APPEARANCE...BUT IS STILL PRODUCING COPIOUS LIGHTNING. THERE IS A SEGMENT OVER SRN WV THAT WILL CONTINUE TRACKING EAST TO OUR SWRN ZONES AND OTHER ACTIVITY COULD FORM OVER THE TERRAIN. 15Z HRRR IS SIMILAR TO OTHER RECENT RUNS WITH ORGANIZED ACTIVITY FROM THE MIDWEST DELAYED FOR THE LWX CWA UNTIL LATE TONIGHT/THURSDAY MORNING. TEMPS A FEW LESS DEGREES THURSDAY WITH 18C 850MB TEMPS COMPARED TO 20C TODAY. FURTHERMORE...SHOULD PRECIP BE GOING ON DURING THE DAY...OR CLOUD COVER THICK ENOUGH...MAX TEMPERATURES COULD BE SEVERAL DEGREES LESS (PERHAPS UPR 80S). && .SHORT TERM /THURSDAY NIGHT/... COLD FRONT/BOUNDARY STALLS SOUTH OF THE AREA THURSDAY NIGHT THROUGH FRIDAY WITH A QUIET PERIOD IN AN OTHERWISE ACTIVE SPELL. BRIEF COOL DOWN THAT CONTINUES INTO THE WEEKEND (AS LONG AS THE BOUNDARY STAYS SOUTH). WILL NEED TO LOOK OUT FOR SHORTWAVES RIDING THE BOUNDARY...SUCH AS THE 12Z ECMWF SOLUTION WITH A FRIDAY NIGHT/SATURDAY MORNING WAVE CROSSING THE AREA. && .LONG TERM /FRIDAY THROUGH WEDNESDAY/... COMBINED MOIST WARM AIRMASS ALONG WITH A QUASI-STATIONARY BOUNDARY AND WEAK PVA CONTINUES TO SUPPORT A CHANCE OF SHOWERS AND AFTERNOON THUNDERSTORMS THROUGH THE PERIOD. SURFACE LOW PRESSURE CENTER TRACKING EAST ALONG THE BOUNDARY WILL SUPPORT THE ENHANCED DEVELOPMENT OF SHOWERS AND THUNDERSTORMS WEDNESDAY. && .AVIATION /20Z WEDNESDAY THROUGH MONDAY/... VFR INTO THIS EVENING OUTSIDE OF ISOLATED TSRA MAINLY ALONG A EAST-WEST BOUNDARY ACROSS THE DCA AREA AND FROM THE TERRAIN WEST OF DC METROS. CU FIELD BASED AROUND 5 KFT. ORGANIZED THUNDERSTORM COMPLEX COULD APPROACH THE TERMINALS LATE TONIGHT OR THURSDAY MORNING. FRONTAL BOUNDARY SOUTH OF THE TERMINALS THURSDAY NIGHT AND FRIDAY BEFORE DRIFTING NORTH THIS WEEKEND. && .MARINE... WLY/NWLY FLOW AROUND 10 KT WITH ISOLATED SHOWERS AND THUNDERSTORMS FROM DC TO CENTRAL MD. ORGANIZED THUNDERSTORM SYSTEM POSSIBLE REACHES THE BAY LATE TONIGHT OR THURSDAY MORNING. FRONTAL BOUNDARY SOUTH OF THE WATERS THURSDAY NIGHT INTO THE WEEKEND. NO SCA IN THE OUTLOOK PERIOD. && .CLIMATE... A RECORD HIGH TEMPERATURE WAS REPORTED AT REAGAN NATIONAL AIRPORT YESTERDAY. THE HIGH WAS 97 DEGREES AND THIS SURPASSES THE OLD RECORD OF 95 DEGREES SET IN 1991...1957...AND 1945. MORE RECORD HIGHS ARE POSSIBLE TODAY AT BWI AND DCA. THE LIST BELOW IS THE RECORD HIGHS FOR THE THREE MAJOR AIRPORTS. KBWI: RECORD HIGH: 97 IN 1957. KDCA: RECORD HIGH: 97 IN 1944. KIAD: RECORD HIGH: 94 IN 2007. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...NONE. VA...NONE. WV...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ530- 531-538-539. && $$ SYNOPSIS...BAJ NEAR TERM...BAJ SHORT TERM...BAJ LONG TERM...CEM AVIATION...BAJ MARINE...BAJ CLIMATE...BAJ
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
332 PM EDT WED JUN 18 2014 LATEST UPDATE... SYNOPSIS/SHORT TERM/LONG TERM/MARINE .SYNOPSIS... ISSUED AT 330 PM EDT WED JUN 18 2014 OCCASIONAL THUNDERSTORMS WILL CONTINUE OVERNIGHT BUT THERE SHOULD BE A BREAK ON THURSDAY INTO THURSDAY NIGHT BEFORE THE STORMS RETURN ON FRIDAY AND OVER THE WEEKEND. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT) ISSUED AT 330 PM EDT WED JUN 18 2014 LINE OF STORMS DEPARTING THE EASTERN FORECAST AREA LATE THIS AFTERNOON WITH A LULL EXPECTED INTO EARLY THIS EVENING. AIRMASS SHOULD GET A CHANCE TO DESTABILIZE BEFORE SUNSET...WHICH ALLOWS NEW STORMS TO FIRE UP AS AN MCV TRACKS ACROSS THE SOUTHERN FORECAST AREA. THIS HAS BEEN INDICATED BY THE HRRR AS WELL AS THE 12Z GFS AND ECMWF. POPS AND QPF SHADED HIGHER ACROSS THE SOUTH. STORMS DIMINISH THURSDAY UNDER SHORT WAVE RIDGING AND PICK UP AGAIN FRIDAY. .LONG TERM...(SATURDAY THROUGH WEDNESDAY) ISSUED AT 330 PM EDT WED JUN 18 2014 QUASI ZONAL FLOW WILL RESULT IN WEAK UPPER IMPULSES MOVING ACROSS THE UPPER MIDWEST DURING THE PERIOD. ONE OF THOSE WAVES WILL PUSH A WEAK COLD FRONT EAST THROUGH THE GREAT LAKES SUNDAY. THIS FRONTAL BOUNDARY WILL LINGER ACROSS THE CWA FOR SEVERAL DAYS AS LOW PRESSURE IN THE CENTRAL PLAINS SLOWLY MOVES ENE. WE/LL HAVE CHC POPS BEGINNING SUNDAY AND CARRY THAT THROUGH MUCH OF THE REST OF THE PERIOD. GFS AND ECMWF ARE IN REASONABLE AGREEMENT MOVING THE LOW TO ILLINOIS BY WEDNESDAY. THE ECMWF HAS HIGHER QPF VS THE GFS BUT BOTH SHOW SHOWERS. WE/LL LIKELY HAVE TO INCREASE POPS FOR THE MIDDLE OF NEXT WEEK IF THE TREND CONTINUES. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 155 PM EDT WED JUN 18 2014 TSRA WILL IMPACT KLAN/KJXN/KBTL/KAZO FOR A COUPLE OF HOURS THIS AFTERNOON. THEN A FEW HOUR BREAK BEFORE MORE STORMS DEVELOP AND AFFECT ALL TAF SITES LATE THIS AFTERNOON AND EARLY EVENING. OVERNIGHT...WINDS WILL BE LIGHT AND CIGS/VSBYS WILL FALL DUE TO ABUNDANT LOW LEVEL MOISTURE. MVFR/IFR EXPECTED AFTER 05Z. && .MARINE... ISSUED AT 317 PM EDT WED JUN 18 2014 SHOWERS AND THUNDERSTORMS...ALONG WITH AREAS OF FOG...WILL PERSIST OVERNIGHT. WINDS AND WAVES WILL BE LOCALLY HIGHER IN AND NEAR THUNDERSTORMS...BUT OTHERWISE REMAIN BLO SMALL CRAFT ADVISORY THE NEXT COUPLE DAYS. && .HYDROLOGY... ISSUED AT 100 PM EDT WED JUN 18 2014 RIVERS ARE RUNNING WELL WITHIN THEIR BANKS AND NEAR NORMAL LEVELS FOR THIS TIME OF YEAR. HOWEVER... THE GRAND AND MUSKEGON RIVERS ARE BEGINNING TO SLOWLY RISE DUE TO THE RAIN FROM TUESDAY AND TODAY. ONLY THE ROGUE RIVER AT ROCKFORD LOOKS LIKE IT MAY RISE TO NEAR BANKFULL... AND THAT WOULD BE TOMORROW. ADDITIONAL RAIN THIS AFTERNOON SHOULD ADD LITTLE ADDITIONAL RISE TO THE RIVERS. THURSDAY MIGHT BE A DRY DAY... BUT ADDITIONAL RAINFALL THURSDAY NIGHT AND FRIDAY COULD BRING MORE POINTS UP TO NEAR BANKFULL. RIVER FLOODING IS NOT EXPECTED. MINOR AREAL FLOODING IS A POSSIBILITY DUE TO THE HEAVY RAIN IN THE THUNDERSTORMS. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR MIZ043>045- 050>052-056>059-064>067-071>074. LM...NONE. && $$ SYNOPSIS...OSTUNO SHORT TERM...OSTUNO LONG TERM...93 AVIATION...93 HYDROLOGY...63 MARINE...OSTUNO
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1222 PM CDT WED JUN 18 2014 .UPDATE... FOR 18Z AVIATION DISCUSSION BELOW && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 311 AM CDT WED JUN 18 2014 YET ANOTHER STORMY SHORT TERM PERIOD IS ON TAP WITH THIS PERIOD LOOKING TO CONTINUE THE TREAT FOR SEVERE WEATHER AND FLASH FLOODING. AT 4 AM...THE WARM FRONT WAS SPLAYED OUT FROM NEAR YANKTON ENE TO JUST NORTH OF I-90 IN SRN MN. YET ANOTHER ENHANCEMENT OF THE LLJ HAS PROVIDED ENOUGH ISENTROPIC LIFT TO OVERCOME THE CAP THE MOVED IN YESTERDAY TO ALLOW THUNDERSTORMS TO BLOSSOM ACROSS THE MN/IA BORDER REGION. STORMS IN THE MPX CWA HAVE REMAINED MAINLY ELEVATED...THOUGH STORMS ACROSS NRN IA HAVE BEEN ABLE TO BASICALLY MAINTAIN THEIR SFC CONNECTION...HENCE THE TORNADO THAT HAPPENED IN THE SPENCER AREA AFTER 1 AM. THOUGH NOT ROOTED AT THE SFC...PWATS NEAR 1.75" COMBINED WITH FREEZING LEVELS OVER 14K FEET HAS RESULTED IN RAINFALL RATES IN EXCESS OF 2 IN/HR OVERNIGHT. EXPECT THIS ACTIVITY TO SLOWLY DRIFT EAST WHILE WEAKENING OVER THE NEXT FEW HOURS AS THE LLJ BEGINS TO VEER OVER TO THE EAST AND WEAKEN THE REST OF THE MORNING. BASED ON THE HRRR AND RAP H85 MOISTURE TRANSPORT FORECAST...EXPECT THIS ACTIVITY TO HANG AROUND THROUGH ABOUT 15Z BEFORE WE GET INTO ANOTHER PRECIP BREAK THAT LOOKS TO LAST MOST OF THE AFTERNOON. MAIN QUESTION FOR THIS AFTERNOON IS WHERE WILL THE WARM FRONT SETUP. ACTIVITY RIGHT NOW WILL AGAIN FORCE THE WARM FRONT SOUTH INTO IA...LIKELY DOWN TO NEAR THE I-80 CORRIDOR. IN ADDITION TO THAT...IN THE WAKE OF THIS MORNINGS CONVECTION...THE RAP SHOWS THE 12C ISOTHERM AT H7 WORKING BACK UP INTO CENTRAL MN...WHICH WILL PUT A LID ON THINGS THROUGH THE AFTERNOON...MUCH LIKE WE JUST SAW YESTERDAY. LOOKING AT LLJ EVOLUTION...DURING THE AFTERNOON...IT WILL BACK TOWARD THE NORTHWEST AND STRENGTHEN ACROSS THE ERN DAKOTAS...WHICH WILL SHIFT THE FOCUS FOR THUNDERSTORMS FROM THE MS VALLEY BACK INTO THE DAKOTAS BY THE AFTERNOON. AS A RESULT...DELAYED ANY RAMP UP IN POPS TO LIKELIES UNTIL AFTER 00Z...TRYING ORIENT THINGS TOWARD THE NSSL/NMM/ARW WRFS...WHICH SHOW STORMS BLOSSOMING ONCE AGAIN AFTER 3Z. THIS IS IN CONJUNCTION WITH THE ARRIVAL OF THE WARM FRONT...WHICH LOOKS TO SURGE NORTH OUT OF IA THIS EVENING IN RESPONSE TO THE SFC LOW CURRENTLY OVER NE COLORADO WORKING OVER TO NEAR ABERDEEN TONIGHT. WHAT DOES THIS MEAN FOR THE SEVERE THREAT? WELL...ONE THING THAT IS FOR SURE IS INSTABILITY WILL NOT BE ISSUE...AS WE SHOULD SEE MLCAPES IN THE WARM SECTOR AGAIN PUSH 5000 J/KG. FOR A TORNADO THREAT...WE WOULD HAVE TO BANK ON ACTIVITY FORMING ALONG THE WARM FRONT AS IT MOVES NORTH. INSTEAD...FEEL OUR MAIN SEVERE THREAT WILL EXIST MAINLY OVERNIGHT WITH ANY SORT OF SYSTEM THAT COMES OUT OF THE DAKOTAS DURING THE AFTERNOON ALONG WITH STORMS THAT DEVELOP NORTH OF THE WARM FRONT AS IT WORKS INTO MN OVERNIGHT. DEEP LAYER SHEAR LOOKS TO BE MARGINALLY WEAKER WEDNESDAY GIVEN THE PRESENCE OF AN UPPER RIDGE...BUT THE STRONG INSTABILITY AND STEEP MID-LEVEL LAPSE RATES WILL BE MORE THAN ENOUGH TO KEEP A WIND/HAIL TREAT GOING THROUGH MUCH OF THE NIGHT. THERE WILL ALSO BE A CONTINUED FLASH FLOOD THREAT WITH THIS ACTIVITY AS WELL. DECIDED ON NOT ISSUING A FLASH FLOOD WATCH AT THIS TIME AS THERE IS ENOUGH UNCERTAINTY AS TO WHERE THIS ROUND OF HEAVY RAIN WILL SET UP THAT IT WAS TO DIFFICULT TO NARROW DOWN A CORRIDOR FOR WHERE ONE WOULD BE NEEDED. WITH THE 00Z CAMS...THERE IS A FAVORED CORRIDOR FOR HEAVY PRECIP FROM SE MN BACK NW TOWARD THE MN/ND/SD BORDER. HOWEVER...THIS WILL LIKELY CHANGE ONCE IT IS BETTER KNOWN WHERE THAT WARM FRONT SETS UP THIS EVENING. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 311 AM CDT WED JUN 18 2014 CONVECTION SHOULD BE ONGOING THURSDAY MORNING WITH A MODEST LLJ AND 925-850MB MOISTURE TRANSPORT ACROSS THE ENTIRE FORECAST AREA. A NW-SE ORIENTATED WARM FRONT SHOULD EXTEND ROUGHLY FROM FARGO...TO DAVENPORT...TO CHICAGO BY 12Z THURSDAY MORNING. THIS WILL BE THE FOCUS FOR SCATTERED TO NUMEROUS THUNDERSTORMS. PWATS SHOULD STILL BE RUNNING HIGH WITH 1.50-1.90" ACROSS THE FORECAST AREA AND THE MEAN STEERING WINDS INDICATE A SLOWER STORM MOTION...THEREFORE FLASH FLOODING WILL CONTINUE TO BE A THREAT. THE OVERALL RISK FOR SEVERE APPEARS FAIRLY LOW...BUT THERE IS ENOUGH DEEP LAYER SHEAR AND MODEST STABILITY TO PROVIDE A MINOR WIND AND HAIL THREAT. THE COLD FRONT AND GRADUALLY FILLING SURFACE LOW WILL EXTEND BACK TOWARD THE WEST IN THE CENTRAL AND NORTHERN PLAINS. THE FRONTAL BOUNDARIES WILL LOSE SOME OF THEIR DEFINITION AS THEY MOVE EAST...BUT A SLIGHTLY DRIER AIR MASS ENTERS WESTERN MN BY THURSDAY AFTERNOON AND EVENING. FRIDAY COULD ACTUALLY BE A DRY DAY ACROSS MOST OF MN WITH THE BOUNDARIES HAVING SHIFTED EAST INTO CENTRAL AND EASTERN WI AND THE LOW LEVEL FLOW BECOMING MUCH WEAKER. A WARM AND MAINLY ZONAL PATTERN SETS UP FOR THE WEEKEND...BUT THERE IS STILL A WEAK SURFACE TROUGH HANGING AROUND THE FORECAST AREA...SO WE CAN SIMPLY NOT GO WITH A DRY FORECAST. THE GOOD NEWS LOCALLY /BAD NEWS FOR SOGGY IA/ IS THAT THE NOCTURNAL LLJ FOCUSES SOUTH OF THE AREA FRI/SAT/SUN. THIS SUGGESTS A LOWER THREAT FOR HEAVY RAIN AND FLASH FLOODING. TEMPERATURES LOOK TO REMAIN NEAR OR ABOVE NORMAL THROUGH EARLY NEXT WEEK. THE 18.00Z ECMWF BRINGS A PSEUDO BACK DOOR COLD FRONT ACROSS THE AREA ON TUE-WED...BUT THE PAST COUPLE RUNS OF THE GFS DOES NOT SHOW IT AT THIS TIME. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 1222 PM CDT WED JUN 18 2014 EXPECTING WARM TEMPERATURES AT THE MID LEVELS OF THE ATMOSPHERE TO CAP OFF THUNDERSTORM DEVELOPMENT THIS AFTERNOON...SO WILL LIKELY BE UNTIL AFTER DARK UNTIL MOST SITES SEE ANY SHRA/TS ACTIVITY. EXPECT STORMS TO DEVELOP AGAIN TO THE WEST/SOUTH AND LIFT INTO THE AREA THIS EVE/OVERNIGHT. HAVE INCLUDED TEMPOS FOR SAID EXPECTATION...ALONG WITH CIG/VSBY REDUCTIONS TO MVFR. WILL QUITE POSSIBLY SEE SHRA LINGER ON THURSDAY AND PROLONGED MVFR CONDITIONS WITH THE WARM FRONT BISECTING THE AREA...WITH MORE WIDESPREAD THUNDERSTORMS EXPECTED LATE THURSDAY AFTERNOON/EVE AS THE COLD FRONT FINALLY BEGINS TO MAKE ITS WAY EASTWARD ACROSS THE AREA. KMSP... BKN MVFR LEVEL DECK SHOULD CONTINUE SCOURING OUT THIS AFTERNOON WITH VFR CONDITIONS THEN EXPECTED UNTIL AFTER DARK WHEN SHRA/TS CHANCES INCREASE. EXPECT THE HIGHEST LIKELIHOOD OF ORGANIZED ACTIVITY TO OCCUR BETWEEN 04Z AND 09Z...WITH HIT OR MISS SHOWERS AFTER THAT. DO EXPECT A BKN MVFR LEVEL DECK TO STICK AROUND THURSDAY...WITH MORE ORGANIZED TS ACTIVITY ARRIVING AFTER 20Z AS THE COLD FRONT APPROACHES. /OUTLOOK FOR KMSP/ FRI...VFR. MVFR SHRA/TSRA POSSIBLE. WINDS SW 10 KTS. SAT...VFR. MVFR SHRA/TSRA POSSIBLE. WINDS W 10 KTS. SUN...VFR. MVFR SHRA/TSRA POSSIBLE. WINDS WNW 10 KTS. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ SHORT TERM...MPG LONG TERM...CLF AVIATION...LS
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
111 PM CDT WED JUN 18 2014 .SHORT TERM...(TODAY THROUGH FRIDAY) ISSUED AT 400 AM CDT WED JUN 18 2014 FORECAST CONCERNS THROUGH THE SHORT TERM WILL CONTINUE TO BE TRYING TO PIN DOWN THUNDERSTORM/SEVERE WEATHER CHANCES ALONG WITH THE HEAT ON WEDNESDAY. AN ISOLATED TORNADIC THUNDERSTORM INDEED DEVELOPED NEAR THE SOUTH DAKOTA BORDER THIS EVENING AND LASTED FOR SEVERAL HOURS OVER CEDAR COUNTY. THE 00Z OAX SOUNDING WAS IMPRESSIVE WITH CAPE OF NEARLY 6400 J/KG AND LITTLE CIN. ALSO OF NOTE WERE THE VERY STEEP LAPSE RATES AND H85 MOISTURE OF 17 DEG. C. A RARE 06Z SOUNDING WAS REQUESTED AND SHOWED AN UNSTABLE ATMOSPHERE WITH NEARLY 5000 J/KG OF CAPE AND 1.64 PWAT. EARLY THIS MORNING...THE MAIN CONVECTIVE COMPLEX IS OVER SOUTHERN MINNESOTA AND NORTHERN IOWA...CLOSER TO THE SURFACE AND H85 WARM FRONT. THE LOW LEVEL JET IS FORECAST TO REMAIN STRONG...40-50KTS OVER KANSAS AND MISSOURI THROUGH 15Z AND THERE IS AN APPROACHING H5 SPEED MAX. IT IS UNCERTAIN IF THIS LOW LEVEL JET CAN GET SOMETHING ELEVATED GOING OVER SOUTHEAST NEBRASKA AND SOUTHWEST IOWA. MOST OF THE OPERATIONAL MODELS ARE DRY THROUGH 21Z. THE EAX 4KM WRF HINTS AT SOMETHING IN THE MORNING ALONG WITH THE SREF. WILL LEAVE MOST OF THE FORECAST AREA DRY...HOWEVER WILL KEEP A SMALL POP IN FOR SOUTHWEST IOWA SHOULD SOMETHING ELEVATED MANAGE TO DEVELOP. THIS WILL NEED TO BE MONITORED THIS A.M. THIS AFTERNOON...THE HEAT BUILDS INTO THE FORECAST AREA WITH HIGHS AGAIN IN THE 90S. MEANWHILE...THE COLD FRONT IS FORECAST TO MOVE INTO CENTRAL NEBRASKA AND THE UPPER LEVEL SUPPORT MOVES INTO THE ROCKIES. THERE ARE A COUPLE OF LOCATIONS FOR CONVECTION...THE PRIMARY FOCUS APPEARS TO BE CLOSER TO THE HEIGHT FALLS...THE COLD FRONT AND THE DEEPENING SURFACE LOW. A SECOND AREA OF CONVECTION MAY DEVELOP IN IOWA AND BUILD BACK INTO THE FORECAST AREA. THE RAP SHOWS A CAP THIS MORNING WITH ELEVATED INSTABILITY AND DESTABILIZATION THIS AFTERNOON WITH THE EROSION OF THE CAP AFTER 20Z AND VERY STEEP LAPSE RATES WITH CAPE AROUND 3000 J/KG. THE NAM/GFS ARE MORE AGGRESSIVE WITH INSTABILITY WITH CAPE OF 4000-6000 J/KG. THE NAM HAS STRONGER DEEP LAYER SHEAR NEAR THE MISSOURI RIVER INTO WESTERN IOWA...WHILE THE GFS HOLDS THE STRONGER SHEAR TO THE WEST OF THE FORECAST AREA UNTIL AFTER MIDNIGHT. WITH HIGH INSTABILITY IN PLACE...SEVERE WEATHER WILL BE POSSIBLE WHERE STORMS DEVELOP. THE STORM PREDICTION CENTER HAS THE ENTIRE FORECAST AREA IN THE SLIGHT RISK AREA. WILL BEGIN TO INCREASE THUNDERSTORM CHANCES LATER THIS AFTERNOON AND CONTINUE TONIGHT AND THURSDAY AS THE UPPER LEVEL STORM SYSTEM MOVES INTO THE PLAINS AND DRIVES THE COLD FRONT THROUGH. WITH THE HIGH INSTABILITY AND FRONTAL BOUNDARIES THERE WILL BE A TORNADO THREAT. THE RAP HAS MORE OF A PRONOUNCED DRYLINE WORKING INTO CENTRAL AND NORTHEAST NEBRASKA. THE NAM HAS A DOUBLE WARMFRONT STRUCTURE WITH NORTHEAST NEBRASKA AND PARTS OF WEST IOWA ALONG WITH AREAS IN SD/MN WITH BACKED FLOW...WHILE THE GFS/EC IS FARTHER NORTH. PLACEMENT OF THESE FEATURES WILL BE KEY TO WHERE THE HIGHER TORNADO POTENTIAL IS. HAIL AND DAMAGING WINDS WILL BE POSSIBLE WITH THE CONVECTIVE COMPLEXES THAT DEVELOP TONIGHT AND THURSDAY. DEEP MOISTURE WITH PWATS OF 1.5 TO 2 INCHES RETURN AND LOCALLY HEAVY RAINFALL IS POSSIBLE...ESPECIALLY WHERE CONVERGENCE IS INCREASED IN THE VICINITY OF THE FRONTS. HIGH TEMPERATURES SHOULD TOP OUT IN THE 90S WITH HEAT INDEX VALUES AGAIN AROUND 100. THURSDAY/S HIGHS SHOULD BE IN THE 80S. THERE IS A BREAK IN THE RAIN CHANCES THURSDAY NIGHT...HOWEVER THE PUSH OF THE SHORTWAVE WEAKEN AND RETURN FLOW INCREASES WITH THE CHANCE FOR RAIN. .LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY) ISSUED AT 400 AM CDT WED JUN 18 2014 THE EXTENDED REMAINS UNSETTLED WITH AT OR BELOW NORMAL HIGHS IN THE 80S. && .AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 101 PM CDT WED JUN 18 2014 AT 18Z...TAF SITES WERE BETWEEN WARM FRONT ACROSS NORTHEAST NEBRASKA INTO NORTHWEST IOWA AND COLD FRONT OVER CENTRAL NEBRASKA. EXPECT MAINLY VFR CONDITIONS OUTSIDE OF THUNDERSTORMS THROUGH THE PERIOD. AN INCREASING CHANCE OF STORMS AFTER 06Z AS SURFACE LOW PRESSURE LOCATED OVER NORTH CENTRAL NEBRASKA AT 18Z TRACKS NORTHEAST INTO SOUTHEAST SOUTH DAKOTA AND COLD FRONT PUSHES INTO EASTERN NEBRASKA. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ SHORT TERM...ZAPOTOCNY LONG TERM...ZAPOTOCNY AVIATION...FOBERT
AREA FORECAST DISCUSSION
NWS BUFFALO NY
558 PM EDT WED JUN 18 2014 .SYNOPSIS... A FEW SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE ACROSS FAR SOUTHWESTERN NEW YORK LATER THIS EVENING AS A STORM SYSTEM OVER THE GREAT LAKES DIVES TO OUR SOUTH. OTHERWISE IT WILL BE A DRY NIGHT FOLLOWED BY INCREASING SUNSHINE AND COOLER TEMPERATURES ON THURSDAY AS HIGH PRESSURE BUILDS ACROSS THE REGION FROM CANADA. FAIR WEATHER AND SEASONABLE TEMPERATURES WILL THEN PERSIST THROUGH THE END OF THE WEEK AND INTO THE COMING WEEKEND AS HIGH PRESSURE DRIFTS OVERHEAD. && .NEAR TERM /THROUGH THURSDAY/... THE DOMINANT FEATURE ON REGIONAL RADAR IMAGERY LATE THIS AFTERNOON IS A RATHER OMINOUS LOOKING MCS CURRENTLY TRACKING ACROSS LOWER MICHIGAN. MESOANALYSIS SHOWS THAT MOST OF WESTERN NEW YORK IS UNDER A STABLE AIRMASS WITH A SURFACE FRONTAL BOUNDARY TO OUR SOUTH OVER PA. HOWEVER...EXTRAPOLATED RADAR TRENDS WHICH ARE SUPPORTED BY THE HRRR HAVE THE REMNANTS OF THIS MCS CLIPPING THE SOUTHERN TIER NEAR THE NY/PA BORDER WHERE THERE IS MODEST CAPES OF 500 TO 1000 J/KG. IT STILL APPEARS THE HEAVIEST RAIN WILL STAY TO THE SOUTH OF OUR CWA...BUT THERE PROBABLY WILL BE AT LEAST MEASURABLE PRECIPITATION SOUTH OF A DKK-ELZ LINE. THE NORTHERN PORTION OF THIS COMPLEX WILL WEAKEN AS IT MOVES EAST...BUT MAY BRING A SHOWER OR SPRINKLE FROM THE NIAGARA FRONTIER TO GENESEE VALLEY LATE THIS EVENING. OTHERWISE...SOME SHOWERS HAVE ALSO POPPED UP ALONG THE ST LAWRENCE ALONG THE CONVERGENCE OF A LARGE SCALE NW FLOW AND A SW LAKE BREEZE. THESE INSTABILITY SHOWERS WILL TAPER OFF THIS EVENING. LATER TONIGHT THE FRONTAL BOUNDARY WILL SAG SOUTH AND SET UP A NORTH- NORTHWESTERLY FLOW ADVECTING COOLER AND MUCH DRIER AIR WILL BEGIN TO TAKE HOLD ACROSS THE REGION AS SURFACE HIGH PRESSURE BUILDS SOUTH OUT OF CANADA. TEMPERATURES WILL COOL INTO THE MID TO UPPER 50S OVERNIGHT...COOLEST ACROSS THE NORTH COUNTRY...WITH COOLING INHIBITED SOMEWHAT BY THE ABUNDANT CLOUD COVER ASSOCIATED THE TROUGH. LOOK FOR WIDESPREAD SUNSHINE AND FAIR WEATHER ON THURSDAY AS A MUCH COOLER AND DRIER AIRMASS WILL DISPLACE THE LINGERING MOISTURE IN PLACE OVER THE REGION. THIS SHOULD YIELD A FINE DAY ACROSS THE FORECAST AREA WITH HIGHS TOPPING OUT IN THE MID 70S...WITH 60S ALONG THE LAKE ONTARIO SHERLINE. && .SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY NIGHT/... SURFACE HIGH PRESSURE CENTERED OVER JAMES BAY WILL CONTINUE TO BUILD SOUTH THURSDAY NIGHT WITH A DRY NORTHERLY FLOW PUSHING THE AXIS OF SURFACE MOISTURE SOUTH OF THE NEW YORK BORDER. CLEAR SKIES AND LIGHT SURFACE WINDS COMBINED WITH THE DROPPING DEWPOINTS WILL PROVIDE GOOD RADIATIONAL COOLING OVERNIGHT WITH TEMPS FALLING INTO UPPER TO MID 40S EXCEPT RIGHT ALONG THE LAKE SHORES AND IN URBAN AREAS WHICH WILL BOTTOM OUT IN THE LOW 50S. ALSO EXPECT AT LEAST SOME PATCHY RIVER VALLEY FOG ACROSS THE SOUTHERN TIER. COOLER AND DRIER CONDITIONS WILL LINGER THROUGH FRIDAY WITH HIGH PRESSURE REMAINING RIDGED ACROSS NEW YORK. EXPECTING LOTS OF SUNSHINE TO START THEN SOME CLOUDS WILL INCREASE FROM THE WEST AHEAD OF A MID-LEVEL SHORTWAVE DROPPING SOUTH ACROSS THE CENTRAL GREAT LAKES. SURFACE TEMPS WILL RISE INTO A RANGE OF UPPER 70S ACROSS THE SOUTHERN TIER TO AROUND 70 EAST OF LAKE ONTARIO WHERE 850MB TEMPS WILL FALL TO AROUND 8C. FRIDAY NIGHT THROUGH SATURDAY THE MID-LEVEL SHORTWAVE TROUGH MENTIONED ABOVE WILL CROSS LAKE ERIE BRINGING A CHANCE OF SHOWERS ACROSS THE WESTERN SOUTHERN TIER CLEARING TO THE SOUTH BY SATURDAY NIGHT. THE INSTABILITY AXIS WILL REMAIN WELL TO THE SOUTH SO NOT EXPECTING ANY THUNDER. OUTSIDE OF THE SOUTHERN TIER COUNTIES...EXPECT DRY CONDITIONS. TEMPS WILL REACH INTO THE MID 70S SATURDAY AND FALL INTO THE 50S BOTH FRIDAY AND SATURDAY NIGHTS. METEOROLOGICAL SUMMER BEGINS AT 621AM SATURDAY. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... SURFACE HIGH PRESSURE AND WEAK RIDGING ALOFT WILL BRING A GREAT DAY ON SUNDAY WITH A MIX OF SUN AND CLOUDS AND TEMPS CLIMBING INTO THE 70S. SUNDAY NIGHT AND MONDAY THE SURFACE HIGH LOOKS TO SHIFT EAST OFF THE NEW ENGLAND COAST WHICH WILL BRING A RETURN OF WARM AND MOIST SOUTHERLY FLOW. A GENERAL MODEL SOLUTION SHOWS LOW PRESSURE SHIFTING EAST ACROSS SOUTHERN CANADA WITH A COLD FRONT SLOWLY DROPPING SOUTH ACROSS THE GREAT LAKES THROUGH EARLY TO MID NEXT WEEK. INSTABILITY BEGINS INCREASING MONDAY WITH A CHANCE FOR SOME DIURNALLY TRIGGERED AFTERNOON STORMS THEN TUESDAY AND WEDNESDAY THE APPROACHING FRONT WILL PROVIDE FORCING FOR PERIODS OF SHOWERS AND THUNDERSTORMS. WENT WITH BROADBRUSH CHANCE POPS MON-WED TO COVER FOR THE CONVECTION BUT TIMING AND LOCATION WILL NEED TO BE FINE TUNED OVER THE NEXT FEW DAYS. TEMPS WILL RUN WITHIN A FEW DEGREES OF AVERAGE FOR LATE JUNE. && .AVIATION /22Z WEDNESDAY THROUGH MONDAY/... EXPECT MAINLY VFR CONDITIONS THIS EVENING. THE ONLY AREA OF CONCERN IS JHW...WHERE SHOWERS AND POSSIBLY A THUNDERSTORMS WILL PROBABLY MOVE THROUGH LATE THIS EVENING. MID-LEVEL CLOUD COVER WILL LINGER THROUGHOUT MUCH OF THE NIGHT AS AN UPPER LEVEL TROUGH CROSSES THE REGION. ANY REMNANT CONVECTION FROM THE MCS CURRENTLY OVER THE CENTRAL GREAT LAKES SHOULD SLIDE SOUTH OF THE NY/PA BORDER WITH THE ONLY OTHER AFFECTS BEING SOME MVFR CIGS OVER THE HIGHER TERRAIN OF THE SOUTHERN TIER AFTER 06Z. OTHERWISE...EXPECT CONDITIONS TO IMPROVE TO VFR FROM NORTH TO SOUTH ACROSS THE AREA FROM LATE TONIGHT THROUGH THURSDAY AS HIGH PRESSURE AND MUCH DRIER AIR BUILD INTO THE REGION. OUTLOOK... THURSDAY NIGHT THROUGH FRIDAY SATURDAY...VFR WITH A CHANCE OF SHOWERS IN THE SOUTHERN TIER. SUNDAY...VFR. MONDAY...MAINLY VFR WITH A CHANCE OF SHOWERS. && .MARINE... THERE WILL BE A CHANCE OF SHOWERS AND THUNDERSTORMS TOWARDS THE PA BORDER THIS EVENING AS THE AREA MAY GET CLIPPED BY A THUNDERSTORM COMPLEX DROPPING SOUTHEAST OUT OF THE CENTRAL GREAT LAKES. OTHERWISE...LARGELY TRANQUIL CONDITIONS SHOULD PERSIST ON THE LAKES FROM LATE TONIGHT THROUGH THE WEEKEND AS HIGH PRESSURE DRIFTS ACROSS THE REGION FROM CANADA. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...NONE. MARINE...NONE. && $$ SYNOPSIS...WOOD NEAR TERM...APFFEL/WOOD SHORT TERM...SMITH LONG TERM...SMITH AVIATION...WOOD/APFFEL MARINE...WOOD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
145 PM EDT WED JUN 18 2014 .SYNOPSIS...A STRONG HIGH PRESSURE SYSTEM ALOFT WILL MAINTAIN HOT CONDITIONS ACROSS THE CAROLINAS AND SOUTHERN VIRGINIA THROUGH THURSDAY. A SURFACE FRONT WILL SLIDE SOUTH INTO THE AREA THURSDAY NIGHT AND WILL STALL ACROSS THE REGION THROUGH THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1025 AM WEDNESDAY... THE LATEST SURFACE ANALYSIS SHOWED SLIGHTLY WEAKER SURFACE RIDGING OVER CENTRAL NORTH CAROLINA...AND THE WATER VAPOR IMAGERY AS WELL AS THE 12Z UPPER-AIR ANALYSIS INDICATED A WEAK SHEAR AXIS OVER THE AREA...BETWEEN LOWER PRESSURE OFF OF THE SOUTHEAST COAST AND A WEAK MID-LEVEL RIDGE AXIS NEAR THE MOUNTAINS. OTHERWISE...CONDITIONS ARE SIMILAR TO MONDAY...WITH WEAK EFFECTIVE SHEAR...MIXED-LAYER CAPE THAT SHOULD RISE AT LEAST INTO THE 1000 TO 2000J/KG RANGE...AND DOWNDRAFT CAPE ON THE ORDER OF 1000J/KG. LIMITING FACTORS FOR DEEP CONVECTION WILL BE THE CONTINUED LACK OF GOOD LOW-LEVEL FORCING AND A SLIGHT INCREASE IN TEMPERATURES AROUND 500MB AS SHOWN BY THE RAP SOUNDINGS FOR THE AFTERNOON. MOST UNSTABLE ON THE RAP SOUNDINGS AND ITS INSTABILITY ANALYSES IS TOWARD KFAY...WHERE LIFTED INDICES ARE FORECAST TO -5C OR SO...AND ALSO WHERE THE RAP FORECASTS THE BETTER 850MB THETA-E. THE LATEST SPC MESOANALYSIS SHOWS THE HIGHER K INDICES THERE AS WELL AS OF MID MORNING. THE LATEST HRRR WRF WOULD...SIMILAR TO YESTERDAY...SHOW THE BETTER CHANCES OF DEEP CONVECTION RELATIVE TO THE REST OF CENTRAL NORTH CAROLINA MOSTLY SOUTH OF U.S. 64 AND CLOSER TO THE YADKIN RIVER...WITH LESSER CHANCES TO THE NORTHEAST WHERE STABILITY APPEARS GREATER AND MOISTURE SOMEWHAT LESS. STILL...AS WAS THE CASE MONDAY AFTERNOON...EVEN WHERE THE AIR MASS IS A LITTLE DRIER AN ISOLATED THUNDERSTORM CAN OCCUR...POSSIBLY WITH ENOUGH LIFT COURTESY OF THE PIEDMONT TROUGH AND MID-LEVEL SUPPORT FROM THE SHEAR AXIS. SLOW- MOVING CELLS COULD PRODUCE VERY LOCALLY HEAVY RAIN...AND IN THIS TYPE OF AIR MASS A BRIEF STRONG-TO-SEVERE WIND GUST FROM THE STRONGEST CELL IS POSSIBLE AS HAS BEEN THE CASE LATELY EACH AFTERNOON FROM A CELL OR TWO. 1000-850MB THICKNESSES SUPPORT HIGHS AT OR POSSIBLY SLIGHTLY ABOVE THE WARMER GUIDANCE...FOR HIGHS IN THE MID TO UPPER 90S...CLOSE TO THE RECORD AT KRDU. HEAT INDICES SHOULD BE HIGHEST TOWARD KGSB...KMEB...KFAY AND KCTZ WHERE THERE SHOULD BE A PERIOD WHERE THOSE VALUES CREEP JUST ABOVE 100. ANY LINGERING CONVECTION THIS EVENING WILL DIMINISH WITHIN AN HOUR OR TWO AFTER SUNSET. IN THEIR WAKE...EXPECT MOSTLY CLEAR-PARTLY CLOUDY SKIES. MIN TEMPS NEAR 70- LOWER 70S. && .SHORT TERM /THURSDAY AND THURSDAY NIGHT/... AS OF 315 AM WEDNESDAY... SUBTLE DIFFERENCES BEGIN TO APPEAR THIS PERIOD...NAMELY A GRADUAL WEAKENING OF THE MID-UPPER LEVEL RIDGE. OVERALL...THURSDAY WILL BE SIMILAR TO THE PAST FEW DAYS WITH HOT TEMPERATURES AND A SLIGHT CHANCE OF AN AFTERNOON THUNDERSTORM. LOW LEVEL THICKNESSES STILL SUGGEST MAX TEMPS IN THE MID AND POSSIBLY UPPER 90S. THE LOWERING UPPER LEVEL HEIGHTS WILL ALLOW A CONVECTIVE COMPLEX OVER THE OH VALLEY AND NORTHERN MID ATLANTIC TO DRIFT SOUTHWARD WITH TIME. OUTFLOWS FROM STORMS ASSOCIATED WITH THIS SYSTEM MAY TRIGGER SCATTERED THUNDERSTORMS THURSDAY NIGHT ACROSS ROUGHLY THE NE QUARTER OF CENTRAL NC. THIS IDEA BEING SHARED BY MOST OF THE MODEL GUIDANCE SO WILL INCREASE POPS TO 30-40 PERCENT ACROSS SECTIONS OF THE NE PIEDMONT AND NORTHERN COASTAL PLAIN...TRENDING TO LESS THAN 20 PERCENT ACROSS THE SOUTH. MIN TEMPS MAINLY IN THE LOWER 70S EXPECT NEAR 70 WHERE SKIES REMAIN MOSTLY CLEAR-PARTLY CLOUDY THROUGH THE OVERNIGHT. && .LONG TERM /FRIDAY THROUGH TUESDAY/... AS OF 3 AM WEDNESDAY... MEDIUM RANGE MODELS CONTINUE TO SUGGEST A TRANSITION FROM MID LEVEL RIDGING EXTENDING INTO THE AREA TO A BROAD MID LEVEL TROUGH LATE WEEK INTO THE WEEKEND... WITH NORTHWESTERLY TO WEST-NORTHWESTERLY MID LEVEL FLOW ALLOWING FOR HARD TO TRACK (AT THIS FAR OUT) S/W DISTURBANCES... HELPING TO ENHANCE CONVECTION. AT THE SURFACE... A WEAKENING SURFACE FRONT IS EXPECTED TO APPROACH THE REGION DURING THIS TIME FROM THE NORTH. DO NOT EXPECT THIS FRONT TO BE ABLE TO PUSH THROUGH THE AREA WITH ANY TRUE AIRMASS CHANGE GIVEN THE TIME OF YEAR. INSTEAD... THINK WE WILL SEE A SURFACE TROUGH SHARPEN SOME WITH THE ARRIVAL OF THE CYCLONIC FLOW AND POSSIBLY SLOWLY PUSH EASTWARD AND OR SOUTHWARD THROUGH THE AREA. TRYING TO PICK OUT WHEN THE BEST CHANCE FOR POPS WILL BE IS STILL DIFFICULT AT THIS TIME GIVEN THE TIMING OF HARD TO TRACK DISTURBANCE. HOWEVER... WILL CONTINUE TO TREND THE FORECAST LATE WEEK INTO THE WEEKEND TO 30-40 PERCENT CHANCE OF SHOWERS AND STORMS. THE BEST DEEP LAYER SHEAR WILL REMAIN TO THE NORTH... BUT COULD BE ENHANCED BY A PASSING DISTURBANCE. THUS... CANNOT RULE OUT SOME SEVERE STORMS EACH DAY...WITH THE MAIN THREAT OF DAMAGING WINDS ALONG WITH HEAVY RAIN. HIGH TEMPS WILL GO THROUGH A TRANSITION PERIOD AS WELL... LOW 90S NORTH TO UPPER 90S SOUTH ON FRIDAY... WITH MORE LOWER TO MID 90S DURING THE WEEKEND... WITH POSSIBLY SOME UPPER 80S NORTH. LOWS ARE EXPECTED TO GENERALLY BE AROUND 70/LOWER 70S. MEDIUM RANGE GUIDANCE BEGINS TO DIVERGE A BIT IN HOW THEY HANDEL THE NORTHEAST U.S. TROUGH. HOWEVER... AT THIS TIME THINK WE SHOULD AT LEAST SEE DIURNAL CHANCE FOR SHOWERS AND STORMS EITHER WAY. THUS... WILL CONTINUE CHANCE POPS FOR EACH AFTERNOON AND EVENING... WITH HIGH TEMPS GENERALLY IN THE LOWER 90S WITH MAYBE SOME MID 90S SOUTH. LOWS WILL REMAIN AROUND 70/LOWER 70S. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... AS OF 130 PM WEDNESDAY... ISOLATED TO WIDELY SCATTERED STORMS THIS AFTERNOON SHOULD LARGELY BE CONFINED TO THE SOUTHERN AND WESTERN PORTIONS OF THE FORECAST AREA...IN THE VICINITY OF A WEAK UPPER LEVEL DISTURBANCE OVER THE SOUTH...AND ALONG DIFFERENTIAL HEATING IN THE HIGHER TERRAIN. OUTSIDE OF AFTERNOON CONVECTION AN AREA OF HIGH PRESSURE ALOFT WILL MAINTAIN PREDOMINATELY VFR CONDITIONS THROUGH THURSDAY. SURFACE WINDS WILL REMAIN LIGHT...LESS THAN 10KTS...FROM THE WEST-SOUTHWEST. SHOWERS AND THUNDERSTORMS ARE EXPECTED TO ACCOMPANY A BACK-DOOR COLD FRONT INTO THE AREA THURSDAY NIGHT/EARLY FRIDAY. THE FRONT IS THEN EXPECTED TO STALL OVER THE REGION...SUPPORTING BETTER CHANCES FOR SCATTERED SHOWERS AND THUNDERSTORMS...ESPECIALLY IN THE AFTERNOON AND EVENING. IN ADDITION...AN INCREASING SOUTHERLY LOW LEVEL FLOW WILL INCREASE THE PROBABILITY OF LATE NIGHT AND EARLY MORNING FOG AND STRATUS...AND ASSOCIATED MVFR-IFR CONDITIONS...EACH MORNING STARTING FRIDAY. && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...CBL NEAR TERM...DJF/WSS SHORT TERM...WSS LONG TERM...BSD AVIATION...CBL
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
434 PM EDT WED JUN 18 2014 .SYNOPSIS... DEEP HIGH PRESSURE AND AN ASSOCIATED UPPER LEVEL RIDGE WILL PERSIST THROUGHOUT THE AREA THROUGH THE END OF THE WEEK. THIS WILL KEEP A SEASONABLY WARM AIR MASS IN PLACE THROUGH THE WEEKEND. HIGH PRESSURE WILL WEAKEN AS THE RIDGE BREAKS DOWN BY FRIDAY AFTERNOON WHICH SHOULD YIELD A GREATER COVERAGE OF SHOWERS AND STORMS ACROSS THE ENTIRE AREA OVER THE WEEKEND. && .NEAR TERM /THROUGH THURSDAY/... 430 PM EDT UPDATE...SEVERE STORMS ARE BUILDING ALONG A WEAK BOUNDARY FROM THE NW NC PIEDMONT SW INTO THE ERN UPSTATE. NOT MUCH STORM MOTION WITH THESE STORMS AND SVR WINDS HAVE NOT BEEN A HUGE THREAT...HOWEVER A LOCALIZED WET DOWNBURST IS NOT OUT OF THE QUESTION AS THE STORMS NEAR AN AREA OF HIGHER DCAPE. LARGE HAIL WILL BE THE MAIN THREAT OVER THE NEXT FEW HRS. AS OF 200 PM...CONVECTION IS BLOSSOMING MORE READILY THAN YESTERDAY ACRS THE MTNS. I UPDATED THE POP TO TRY TO MATCH TRENDS. MOST OF THE HIGH TERRAIN LOOKS TO GET WORKED OVER BY THE CONVECTION BY SUNSET. HOWEVER...CONFIDENCE IS STILL LOW ON HOW MUCH WILL DEVELOP ACRS THE PIEDMONT. STORM MOTION IS VERY SLOW...AND CELLS HAVE GENERALLY WEAKENED SO FAR AS THEY TRY TO ROLL OFF THE ESCARPMENT. HOWEVER...THE VIS SAT IMAGERY SHOWS A CUMULUS FIELD GETTING MORE ROBUST...WITH A COUPLE OF ISOLD STORMS DEVELOPING EAST OF CHARLOTTE. THE 15Z-16Z HRRR RUNS ARE SHOWING A CLUSTER OF STORMS DEVELOPING SOUTH CHARLOTTE...WITH OUTFLOW FANNING OUT AND TRIGGERING NEW CELLS ACRS MUCH OF THE PIEDMONT LATE AFTN INTO EARLY EVENING. THE HRRR TENDS TO BE OVERDONE...BUT IT DOES SHOW THE POTENTIAL. SO I DID INCREASE POPS FOR PORTIONS OF THE PIEDMONT...BUT STILL GENERALLY SLGT CHC TO LOW-END CHC. AS FOR SEVERE POTENTIAL...IT LOOKS LIKE CELLS ARE TOPPING OUT JUST SHORT OF OBJECTIVE CRITERIA SO FAR. LAPS CAPE ANALYSIS SHOWS 3000-4000 J/KG ACRS MUCH OF THE PIEDMONT. SO I THINK THERE WILL BE A FEW PULSE SEVERE STORMS...WITH QUARTER-SIZE HAIL AND/OR DAMAGING WINDS. TONIGHT...CONVECTION SHUD WANE QUICKLY AROUND SUNSET. SIMILAR TO LAST COUPLE NIGHTS...CLOUDS SHUD DISSIPATE AND WINDS REMAIN CALM/LIGHT. THERE WILL BE SOME VLY FOG IN THE NC MTNS. TEMPS WILL BE ABOVE NORMAL IN THE 60S MTNS AND UPR 60S TO LWR 70S PIEDMONT. THURSDAY...A SHORTWAVE TROF WILL DIVE INTO THE GREAT LAKES...HELPING WEAKEN THE LARGE UPPER RIDGE ATOP THE CWFA. HOWEVER...GUIDANCE SHOWS ONLY SUBTLE CHANGES IN THE ENVIRONMENT FOR OUR AREA. SO EXPECT ANOTHER HOT DAY WITH SCT-NUM AFTN SHWRS/TSTMS IN THE MTNS AND ISOLD-SCT IN THE PIEDMONT. && .SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/... AS OF 300 PM WEDNESDAY...THE UPPER RIDGE OVER THE CAROLINAS AND GA WILL GRADUALLY BREAK DOWN FROM THE EAST FROM THURSDAY NIGHT THROUGH SATURDAY...AS A LOW AMPLITUDE UPPER TROUGH SETS UP OFF THE EAST COAST. THIS WILL ALLOW A COLD FRONT TO MOVE SOUTH INTO NORTH CAROLINAS ON THURSDAY NIGHT AND FRIDAY. THE GFS STALLS THE FRONT NEAR THE SC BORDER ON FRIDAY NIGHT...WHILE THE NAM IS SLIGHT FARTHER NORTH. IN ANY EVENT AN INCREASE IN CONVECTIVE ACTIVITY IS EXPECTED WITH THE ARRIVAL OF THIS BOUNDARY. MODEL SOUNDING SHOW A BIT MORE SHEAR BY THIS TIME...ALTHOUGH INSTABILITY IS MODEST. ALTHOUGH STEERING FLOW IS BETTER THAN IN PREVIOUS DAYS...MOVING CELLS ALONG...SOME CONCERN EXISTS FOR REPEAT CELLS TRAINING EAST ALONG THE BOUNDARY RESULTING IN HEAVY RAINFALL. TEMPERATURES ARE EXPECTED TO REMAIN ABOVE NORMAL...BUT NOT AS MUCH SO ALONG INTERSTATE 40 WHERE CLOUD COVER WILL BE BEST ALONG THE BOUNDARY. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... AS OF 115 PM EDT WEDNESDAY...THE MEDIUM RANGE FCST PICKS UP AT 00Z ON SUNDAY WITH PERSISTENT UPPER RIDGING TO OUR WEST AND BROAD UPPER TROFFING TO OUR NE. THE PATTERN IS EXPECTED TO FLATTEN OUT EARLY IN THE PERIOD BEFORE ANOTHER...DEEPER UPPER TROF DIGS DOWN OVER THE GREAT LAKES WITH THE TROF AXIS TO OUR NORTH BY THE END OF THE MEDIUM RANGE. THE LONG RANGE MODELS DIFFER A FAIR AMOUNT WRT THE EVOLUTION OF THE UPPER TROF WITH THE ECMWF DEVELOPING A MORE AMPLIFIED AND COHERENT SYSTEM COMPARED TO THE GFS. THE GFS TRIES TO DEVELOP THE TROF 1 TO 2 DAYS EARLIER AND KEEPS IT FARTHER NORTH AS IT PROGRESSES EASTWARD. DIURNAL POPS WERE INCREASED A BIT ON BOTH MON AND TUES NEXT WEEK TO REFLECT GENERALLY MORE MOIST GUIDANCE. OTHER THAN THAT...NO MAJOR CHANGES WERE MADE TO THE SENSIBLE FCST. && .AVIATION /21Z WEDNESDAY THROUGH MONDAY/... AT KCLT...THE ATMOSPHERE APPEARS A BIT MORE UNSTABLE THAN THE EARLIER GUIDANCE LED ON...BASED ON CURRENT TRENDS. NUMEROUS SHRA/TSRA HAVE DEVELOPED ACRS THE SOUTHERN APPALACHIANS...AND THE VIS SAT IMAGERY SHOWS CUMULUS CONGESTUS INCREASING ACRS THE CAROLINA PIEDMONT. THE LATEST HRRR ALLOWS SEVERAL CELLS TO DEVELOP WHERE THIS CONGESTUS IS...SO I THINK THERE WILL BE A FEW STORMS AROUND KCLT THIS AFTN. ENUF TO WARRANT A TEMPO FOR TS. WINDS WILL BE LIGHT AND FAVOR A SW DIRECTION...EXCEPT NEAR TS...WHERE OUTFLOWS WILL BE VARIABLE. CONVECTION SHUD WANE QUICKLY THIS EVENING...WITH LIGHT WINDS AND CLEARING SKIES OVERNIGHT. NOT EXPECTING MUCH FOG POTENTIAL THURSDAY MORNING. ANOTHER ROUND OF DIURNAL SHRA/TSRA EXPECTING SIMILAR TO LAST FEW DAYS...BUT BEYOND THE 18Z TAF PERIOD FOR KCLT. ELSEWHERE...AS MENTIONED ABOVE...CONVECTION WILL BE MAIN CONCERN THIS AFTN. HAVE VCTS AND TEMPO GROUPS FOR TS AT ALL SITES...GIVEN THE SCATTERED NATURE OF STORMS. CHCS ARE STILL ONLY 20-30% FOR DIRECT IMPACT AT MOST SITES...WITH BEST CHC AT KAVL. CONVECTION WANES QUICKLY AFTER SUNSET. GUIDANCE SHOWING SOME FOG POTENTIAL AT KAVL...BUT OTHERWISE...NOT ENUF CONFIDENCE TO MENTION IN THE TAFS. WINDS WILL BE LIGHT...EXCEPT NEAR TSTMS. OUTLOOK...ISOLATED TO SCATTERED AFTERNOON AND EVENING THUNDERSTORMS ARE EXPECTED THROUGH THE WEEK...WITH THE GREATEST COVERAGE ACROSS THE MTNS. RESTRICTIONS MAY OCCUR DURING TSRA AND ALSO IN THE MTN VALLEYS EACH MORNING WHERE LOW CLOUDS AND FOG MAY FORM OVER AREAS OF RECENT RAINFALL. CONFIDENCE TABLE... 20-02Z 02-08Z 08-14Z 14-20Z KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100% KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAVL HIGH 100% HIGH 100% HIGH 100% HIGH 100% KHKY HIGH 100% HIGH 100% HIGH 91% HIGH 100% KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAND HIGH 100% HIGH 100% HIGH 95% HIGH 100% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...STAARMANN NEAR TERM...ARK/SBK SHORT TERM...JAT LONG TERM...JPT AVIATION...ARK
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
226 PM EDT WED JUN 18 2014 .SYNOPSIS... DEEP HIGH PRESSURE AND AN ASSOCIATED UPPER LEVEL RIDGE WILL PERSIST THROUGHOUT THE AREA THROUGH THE END OF THE WEEK. THIS WILL KEEP A SEASONABLY WARM AIR MASS IN PLACE THROUGH THE WEEKEND. HIGH PRESSURE WILL WEAKEN AS THE RIDGE BREAKS DOWN BY FRIDAY AFTERNOON WHICH SHOULD YIELD A GREATER COVERAGE OF SHOWERS AND STORMS ACROSS THE ENTIRE AREA OVER THE WEEKEND. && .NEAR TERM /THROUGH THURSDAY/... AS OF 200 PM...CONVECTION IS BLOSSOMING MORE READILY THAN YESTERDAY ACRS THE MTNS. I UPDATED THE POP TO TRY TO MATCH TRENDS. MOST OF THE HIGH TERRAIN LOOKS TO GET WORKED OVER BY THE CONVECTION BY SUNSET. HOWEVER...CONFIDENCE IS STILL LOW ON HOW MUCH WILL DEVELOP ACRS THE PIEDMONT. STORM MOTION IS VERY SLOW...AND CELLS HAVE GENERALLY WEAKENED SO FAR AS THEY TRY TO ROLL OFF THE ESCARPMENT. HOWEVER...THE VIS SAT IMAGERY SHOWS A CUMULUS FIELD GETTING MORE ROBUST...WITH A COUPLE OF ISOLD STORMS DEVELOPING EAST OF CHARLOTTE. THE 15Z-16Z HRRR RUNS ARE SHOWING A CLUSTER OF STORMS DEVELOPING SOUTH CHARLOTTE...WITH OUTFLOW FANNING OUT AND TRIGGERING NEW CELLS ACRS MUCH OF THE PIEDMONT LATE AFTN INTO EARLY EVENING. THE HRRR TENDS TO BE OVERDONE...BUT IT DOES SHOW THE POTENTIAL. SO I DID INCREASE POPS FOR PORTIONS OF THE PIEDMONT...BUT STILL GENERALLY SLGT CHC TO LOW-END CHC. AS FOR SEVERE POTENTIAL...IT LOOKS LIKE CELLS ARE TOPPING OUT JUST SHORT OF OBJECTIVE CRITERIA SO FAR. LAPS CAPE ANALYSIS SHOWS 3000-4000 J/KG ACRS MUCH OF THE PIEDMONT. SO I THINK THERE WILL BE A FEW PULSE SEVERE STORMS...WITH QUARTER-SIZE HAIL AND/OR DAMAGING WINDS. TONIGHT...CONVECTION SHUD WANE QUICKLY AROUND SUNSET. SIMILAR TO LAST COUPLE NIGHTS...CLOUDS SHUD DISSIPATE AND WINDS REMAIN CALM/LIGHT. THERE WILL BE SOME VLY FOG IN THE NC MTNS. TEMPS WILL BE ABOVE NORMAL IN THE 60S MTNS AND UPR 60S TO LWR 70S PIEDMONT. THURSDAY...A SHORTWAVE TROF WILL DIVE INTO THE GREAT LAKES...HELPING WEAKEN THE LARGE UPPER RIDGE ATOP THE CWFA. HOWEVER...GUIDANCE SHOWS ONLY SUBTLE CHANGES IN THE ENVIRONMENT FOR OUR AREA. SO EXPECT ANOTHER HOT DAY WITH SCT-NUM AFTN SHWRS/TSTMS IN THE MTNS AND ISOLD-SCT IN THE PIEDMONT. && .SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/... AS OF 300 PM WEDNESDAY...THE UPPER RIDGE OVER THE CAROLINAS AND GA WILL GRADUALLY BREAK DOWN FROM THE EAST FROM THURSDAY NIGHT THROUGH SATURDAY...AS A LOW AMPLITUDE UPPER TROUGH SETS UP OFF THE EAST COAST. THIS WILL ALLOW A COLD FRONT TO MOVE SOUTH INTO NORTH CAROLINAS ON THURSDAY NIGHT AND FRIDAY. THE GFS STALLS THE FRONT NEAR THE SC BORDER ON FRIDAY NIGHT...WHILE THE NAM IS SLIGHT FARTHER NORTH. IN ANY EVENT AN INCREASE IN CONVECTIVE ACTIVITY IS EXPECTED WITH THE ARRIVAL OF THIS BOUNDARY. MODEL SOUNDING SHOW A BIT MORE SHEAR BY THIS TIME...ALTHOUGH INSTABILITY IS MODEST. ALTHOUGH STEERING FLOW IS BETTER THAN IN PREVIOUS DAYS...MOVING CELLS ALONG...SOME CONCERN EXISTS FOR REPEAT CELLS TRAINING EAST ALONG THE BOUNDARY RESULTING IN HEAVY RAINFALL. TEMPERATURES ARE EXPECTED TO REMAIN ABOVE NORMAL...BUT NOT AS MUCH SO ALONG INTERSTATE 40 WHERE CLOUD COVER WILL BE BEST ALONG THE BOUNDARY. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... AS OF 115 PM EDT WEDNESDAY...THE MEDIUM RANGE FCST PICKS UP AT 00Z ON SUNDAY WITH PERSISTENT UPPER RIDGING TO OUR WEST AND BROAD UPPER TROFFING TO OUR NE. THE PATTERN IS EXPECTED TO FLATTEN OUT EARLY IN THE PERIOD BEFORE ANOTHER...DEEPER UPPER TROF DIGS DOWN OVER THE GREAT LAKES WITH THE TROF AXIS TO OUR NORTH BY THE END OF THE MEDIUM RANGE. THE LONG RANGE MODELS DIFFER A FAIR AMOUNT WRT THE EVOLUTION OF THE UPPER TROF WITH THE ECMWF DEVELOPING A MORE AMPLIFIED AND COHERENT SYSTEM COMPARED TO THE GFS. THE GFS TRIES TO DEVELOP THE TROF 1 TO 2 DAYS EARLIER AND KEEPS IT FARTHER NORTH AS IT PROGRESSES EASTWARD. DIURNAL POPS WERE INCREASED A BIT ON BOTH MON AND TUES NEXT WEEK TO REFLECT GENERALLY MORE MOIST GUIDANCE. OTHER THAN THAT...NO MAJOR CHANGES WERE MADE TO THE SENSIBLE FCST. && .AVIATION /19Z WEDNESDAY THROUGH MONDAY/... AT KCLT...THE ATMOSPHERE APPEARS A BIT MORE UNSTABLE THAN THE EARLIER GUIDANCE LED ON...BASED ON CURRENT TRENDS. NUMEROUS SHRA/TSRA HAVE DEVELOPED ACRS THE SOUTHERN APPALACHIANS...AND THE VIS SAT IMAGERY SHOWS CUMULUS CONGESTUS INCREASING ACRS THE CAROLINA PIEDMONT. THE LATEST HRRR ALLOWS SEVERAL CELLS TO DEVELOP WHERE THIS CONGESTUS IS...SO I THINK THERE WILL BE A FEW STORMS AROUND KCLT THIS AFTN. ENUF TO WARRANT A TEMPO FOR TS. WINDS WILL BE LIGHT AND FAVOR A SW DIRECTION...EXCEPT NEAR TS...WHERE OUTFLOWS WILL BE VARIABLE. CONVECTION SHUD WANE QUICKLY THIS EVENING...WITH LIGHT WINDS AND CLEARING SKIES OVERNIGHT. NOT EXPECTING MUCH FOG POTENTIAL THURSDAY MORNING. ANOTHER ROUND OF DIURNAL SHRA/TSRA EXPECTING SIMILAR TO LAST FEW DAYS...BUT BEYOND THE 18Z TAF PERIOD FOR KCLT. ELSEWHERE...AS MENTIONED ABOVE...CONVECTION WILL BE MAIN CONCERN THIS AFTN. HAVE VCTS AND TEMPO GROUPS FOR TS AT ALL SITES...GIVEN THE SCATTERED NATURE OF STORMS. CHCS ARE STILL ONLY 20-30% FOR DIRECT IMPACT AT MOST SITES...WITH BEST CHC AT KAVL. CONVECTION WANES QUICKLY AFTER SUNSET. GUIDANCE SHOWING SOME FOG POTENTIAL AT KAVL...BUT OTHERWISE...NOT ENUF CONFIDENCE TO MENTION IN THE TAFS. WINDS WILL BE LIGHT...EXCEPT NEAR TSTMS. OUTLOOK...ISOLATED TO SCATTERED AFTERNOON AND EVENING THUNDERSTORMS ARE EXPECTED THROUGH THE WEEK...WITH THE GREATEST COVERAGE ACROSS THE MTNS. RESTRICTIONS MAY OCCUR DURING TSRA AND ALSO IN THE MTN VALLEYS EACH MORNING WHERE LOW CLOUDS AND FOG MAY FORM OVER AREAS OF RECENT RAINFALL. CONFIDENCE TABLE... 18-24Z 00-06Z 06-12Z 12-18Z KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100% KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAVL HIGH 100% HIGH 100% HIGH 100% HIGH 100% KHKY HIGH 100% HIGH 100% HIGH 91% HIGH 100% KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAND HIGH 100% HIGH 100% HIGH 97% HIGH 100% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...STAARMANN NEAR TERM...ARK SHORT TERM...JAT LONG TERM...JPT AVIATION...ARK
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
308 PM CDT WED JUN 18 2014 .DISCUSSION... GOOD SHOWER/THUNDERSTORM COVERAGE ACROSS PARTS OF SOUTHEAST SO FAR TODAY (MAINLY FROM THE HOUSTON AREA AND OFF TO THE NORTH AND NORTHEAST) HAS BEEN A LOT MORE THAN ANTICIPATED. RAIN GAUGE DATA HAS INDICATED RAINFALL TOTALS IN SOME SPOTS HAVE BEEN BETWEEN 1 AND 2 INCHES...MAINLY ASSOCIATED WITH THE STRONGER ACTIVITY AND WHERE NORTH-SOUTH TRAINING HAS SET UP. THE DISTURBANCE TO OUR SOUTHWEST THAT HAS HELPED GENERATE TODAY`S STORMS WILL BE FIGHTING WITH SOME DRIER AIR (CURRENTLY LOCATED ACROSS THE CENTRAL GULF OF MEXICO) THAT WILL BE SLOWLY EDGING WESTWARD TOWARD THE TEXAS COAST OVER THE NEXT COUPLE OF DAYS. MOST MODELS HAVE THE DRIER AIR WINNING OUT FOR THE REMAINDER OF THE WEEK...BUT THE SAME MODELS DID NOT GET TODAY RIGHT FOR OUR AREA. DECIDED TO KEEP LOW RAIN CHANCES IN THE FORECAST FOR THE REMAINDER OF THE WEEK WITH THE GENERAL IDEA OF POSSIBLE SHOWER DEVELOPMENT DURING THE LATE NIGHT THROUGH EARLY MORNING HOURS NEAR THE COAST...THEN POSSIBLE SHOWER/THUNDERSTORM DEVELOPMENT FURTHER INLAND AS THE DAY PROGRESSES. OVER THE WEEKEND...MID/UPPER LEVEL RIDGING THAT BUILDS ACROSS SOUTHEAST TEXAS MIGHT NOT END UP BEING STRONG ENOUGH TO TOTALLY SHUT DOWN OUR RAINS...AND WE MIGHT END UP NEEDING TO ADD LOW POPS FOR MAINLY DAYTIME DEVELOPMENT. WILL HAVE RAIN COME BACK INTO THE FORECAST FOR THE START OF NEXT WEEK AS RIDGING BREAKS DOWN. 42 && .MARINE... A SMALL CRAFT EXERCISE CAUTION WILL AGAIN BE IN EFFECT THIS EVENING UNTIL 4 AM TOMORROW MORNING. HIGH PRESSURE BEGINS TO MOVE CLOSER TO THE AREA TOMORROW THOUGH WHICH WILL ALLOW THE PRESSURE GRADIENT TO RELAX ALONG WITH THE SURFACE WINDS. LIGHT TO OCCASIONALLY MODERATE WINDS WITH 2 TO 4 FOOT SEAS WILL CONTINUE THROUGH THE WEEKEND. 23 && .PREV DISCUSSION... /ISSUED 1142 AM CDT WED JUN 18 2014/ DISCUSSION... SEE AVIATION FOR 18Z TAF ISSUANCE. AVIATION... SHOWERS AND THUNDERSTORMS HAVE CONTINUED TO INCREASE IN COVERAGE THIS AFTERNOON THANKS TO AMPLE MOISTURE AND LIFT FROM A SHORTWAVE WEST OF THE AREA. FORECAST SOUNDINGS ALSO SUPPORT RAIN THIS AFTERNOON AS PWATS ARE FORECASTED TO BE AROUND 1.70". THE HRRR... TEXAS TECH WRF... AND RAP ALSO INDICATE THE CHANCE OF SHOWERS AND THUNDERSTORMS THIS AFTERNOON. ANOTHER NIGHT OF MVFR CIGS LOOKS POSSIBLE TOMORROW MORNING THANKS TO LINGERING MOISTURE. FOR THURSDAY THE CHANCE OF RAIN LOOKS TO DIMINISH AS MUCH DRIER 850/500 AIR WORKS INTO THE AREA. THERE MIGHT BE A CHANCE OF SOME SHOWERS IN THE MORNING BEFORE THE DRIER AIR ARRIVES BUT CHANCES LOOK LOW. PWATS ARE FORECASTED TO DROP NEAR 1.20" BY TOMORROW EVENING ACROSS THE AREA (AVERAGE VALUES IS ~1.60" FOR THIS TIME OF YEAR). 23 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 74 92 74 93 74 / 30 20 10 20 10 HOUSTON (IAH) 76 91 75 92 75 / 30 20 10 20 10 GALVESTON (GLS) 80 88 80 89 80 / 20 20 20 20 10 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...SMALL CRAFT SHOULD EXERCISE CAUTION THROUGH LATE TONIGHT FOR THE FOLLOWING ZONES: GALVESTON BAY...MATAGORDA BAY...WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM... WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM. && $$ DISCUSSION...42 AVIATION/MARINE...23
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1142 AM CDT WED JUN 18 2014 .DISCUSSION... SEE AVIATION FOR 18Z TAF ISSUANCE. && .AVIATION... SHOWERS AND THUNDERSTORMS HAVE CONTINUED TO INCREASE IN COVERAGE THIS AFTERNOON THANKS TO AMPLE MOISTURE AND LIFT FROM A SHORTWAVE WEST OF THE AREA. FORECAST SOUNDINGS ALSO SUPPORT RAIN THIS AFTERNOON AS PWATS ARE FORECASTED TO BE AROUND 1.70". THE HRRR... TEXAS TECH WRF... AND RAP ALSO INDICATE THE CHANCE OF SHOWERS AND THUNDERSTORMS THIS AFTERNOON. ANOTHER NIGHT OF MVFR CIGS LOOKS POSSIBLE TOMORROW MORNING THANKS TO LINGERING MOISTURE. FOR THURSDAY THE CHANCE OF RAIN LOOKS TO DIMINISH AS MUCH DRIER 850/500 AIR WORKS INTO THE AREA. THERE MIGHT BE A CHANCE OF SOME SHOWERS IN THE MORNING BEFORE THE DRIER AIR ARRIVES BUT CHANCES LOOK LOW. PWATS ARE FORECASTED TO DROP NEAR 1.20" BY TOMORROW EVENING ACROSS THE AREA (AVERAGE VALUES IS ~1.60" FOR THIS TIME OF YEAR). 23 && .PREV DISCUSSION... /ISSUED 1019 AM CDT WED JUN 18 2014/ DISCUSSION... FOR THE MORNING UPDATE...WENT AHEAD AND RAISED TODAY`S RAIN CHANCES A LITTLE BIT TO ACCOUNT FOR CURRENT ACTIVITY SHOWING UP ON RADAR AND HIGH PRECIPITABLE WATER VALUES IN THE AREA. WITH DAYTIME HEATING ANTICIPATE MORE SHOWER/THUNDERSTORM DEVELOPMENT THAT WILL WORK ITS WAY NORTHWARD ACROSS OUR AREA. FORECAST UPDATE IS ALREADY OUT. 42 PREV DISCUSSION... /ISSUED 658 AM CDT WED JUN 18 2014/ DISCUSSION... 12Z TAF DISCUSSION IN AVIATION SECTION. AVIATION... MAINLY VFR CIGS ACROSS SE TX TERMINALS WITH THE EXCEPTION BEGIN CLL. IFR/MVFR CIGS AT CLL SHOULD BE SHORT LIVED. CEILINGS SHOULD LIFT NEXT HOUR OR TWO WITH HEATING. RADAR SHOWS A FEW ISO SHOWERS BUT DO NOT EXPECT ACTIVITY TO DEVELOP OR BECOME MORE WIDESPREAD. CARRY VFR CIGS IN THE AFTERNOON AND THEN REPEAT CONDITIONS FOR TONIGHT. WINDS MAY NOT BE AS STRONG GOING INTO THURSDAY. 39 PREV DISCUSSION... /ISSUED 411 AM CDT WED JUN 18 2014/ DISCUSSION... A MID AND UPPER LEVEL WEAK HIGH PRESSURE RIDGE WAS LOCATED OVER THE UPPER TEXAS COASTAL AREAS EARLY THIS MORNING. ONSHORE FLOW WAS PERSISTENT OVER THE LOWER LEVELS AND SURFACE. A WEAK VORTICITY MAXIMUM WAS MOVING ACROSS SOUTH TEXAS. THE MODELS PICKED UP ON THIS SYSTEM AND MOVE IT INTO THE WESTERN COUNTIES OF THE FORECAST AREA LATER THIS AFTERNOON. THE HIGH RESOLUTION MODELS ARE FAIRLY CONSISTENT IN KEEPING ONLY ISOLATED COVERAGE OVER SE TX TODAY. THE COVERAGE ACTUALLY LOOKS TO BE SIMILAR TO YESTERDAY...WITH ISOLATED CHANCES OVER THE SOUTH THIS MORNING AND WITH THE COVERAGE MAINLY OVER THE NORTHERN COUNTIES THIS AFTERNOON. THE MODEL FORECAST SOUNDINGS BEAR THIS REASONING OUT WITH BEST PW/S AT OR ABOVE 1.8 INCHES AT KCLL DURING THE LATE AFTERNOON. THE MID LEVEL RIDGE THEN BUILDS OVER THE AREA TOMORROW THROUGH THE END OF THE WEEK. THE AIRMASS DRIES OUT AS WELL AS CAN BE SEEN IN THE PW FIELDS AND IN THE 700 MB DEWPOINT FORECASTS ON THE GFS AND ECMWF MODELS. THIS WILL LEAD TO LOW RAIN CHANCES BEGINNING ON THURSDAY...AND A SLIGHT INCREASE IN DAILY TEMPERATURES BY SATURDAY. EARLY NEXT WEEK THE GFS AND ECMWF DEVELOP A WEAKNESS IN THE RIDGE OVER THE AREA. THE AREA OF MOISTURE OVER THE EASTERN AND CENTRAL GULF TRIES TO WORK ITS WAY TO THE WEST...BUT THE 00Z MODEL RUNS KEEP IT MAINLY OFF THE TEXAS COAST. FOR NOW...SLIGHTLY COOLER TEMPERATURES ARE POSSIBLE EARLY NEXT WEEK WHILE RAIN CHANCES WILL PROBABLY HOLD OFF UNTIL THE MID WEEK PERIOD. MARINE... SMALL CRAFT EXERCISE CAUTION SHOULD PERSIST INTO THE MORNING HOURS FOR THE OFFSHORE WATERS AND BAYS OF THE UPPER TX COAST. PRESSURE GRADIENT DOES LOOK TO RELAX SOME THE NEXT COUPLE OF DAYS SO THE NOCTURNAL INCREASE IN WINDS MAY NOT BE AS MUCH TONIGHT INTO THURSDAY. POSSIBLE TO HAVE ONE MORE NIGHT OF SCEC CONDITIONS BUT LIKELY SEE WINDS REMAIN CLOSER TO 10-15KTS WITH SLIGHTLY LOWER SEAS. WINDS AND SEAS SHOULD DECREASE FURTHER FOR THE WEEKEND AS PRESSURE GRADIENT LESSENS FURTHER. OVERALL TYPICAL SUMMER TIME PATTERN WILL CONTINUE. 39 AVIATION... SO FAR LOOKING AT VFR CIGS THIS MORNING WITH PERHAPS SOME ISOLATED AREAS OF MVFR. RADAR STARTING TO SHOW SOME SHOWERS DEVELOPING BUT LESS THAN YESTERDAY. TAFS SHOULD BE ON TRACK AND LOOK FOR SIMILAR CONDITIONS THE NEXT 24 HRS. 39 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 74 92 73 93 73 / 10 10 10 10 10 HOUSTON (IAH) 76 91 75 92 74 / 10 10 10 10 10 GALVESTON (GLS) 80 88 79 89 80 / 10 10 10 10 10 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...SMALL CRAFT SHOULD EXERCISE CAUTION FROM 5 PM CDT THIS AFTERNOON THROUGH LATE TONIGHT FOR THE FOLLOWING ZONES: GALVESTON BAY...MATAGORDA BAY...WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM...WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM. && $$ DISCUSSION...23 AVIATION/MARINE...23
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
148 PM EDT WED JUN 18 2014 .SYNOPSIS... HIGH PRESSURE COVERED MUCH OF THE SOUTHEAST UNITED STATES TODAY. A COLD EXTENDED FROM NEW YORK INTO WISCONSIN. THIS FRONT WILL MOVE SOUTH THROUGH THE OHIO VALLEY AND MID ATLANTIC REGION ON THURSDAY...THEN STALL OVER THE AREA THROUGH THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1200 PM EDT WEDNESDAY... INCREASED THE POPS SLIGHTLY ACROSS THE SOUTHWEST AS ISOLATED THUNDERSTORMS ARE BEGINNING TO POP UP ACROSS RUSSELL COUNTY AND FURTHER BACK ACROSS PIKE COUNTY. HRRR 12Z RUN CONTINUES TO FAVOR SOME DEVELOPMENT ACROSS THE SOUTHWEST AND EAST OF THE BLUE RIDGE ACROSS SOUTHSIDE AND THE PIEDMONT LATER THIS AFTERNOON AND EVENING. WITH SURFACE TEMPS IN THE LOW 90S THIS AFTERNOON AND MU CAPES AROUND 2000 J/KG THE POSSIBILITY WILL EXIST FOR SOME ISOLATED SEVERE STORMS ONCE AGAIN TODAY. LARGE HAIL WOULD BE THE PRIMARY THREAT. STORM MOTION OF 10 KTS IS ONLY SLIGHTLY FASTER THAN YESTERDAY...SO SLOW MOVING STORMS WILL HAVE TO BE WATCHED FOR POSSIBLE FLOODING ESPECIALLY IF ANY STORM CROSSES AN AREA THAT RECEIVED DECENT RAINFALL YESTERDAY. AS OF 840 AM EDT WEDNESDAY... REMOVED FOG FROM THE GRIDS AS DAYTIME HEATING HAS QUICKLY ERODED THE PATCHY FOG THAT WAS STILL HANGING AROUND. ALSO TWEAKED THE NEAR TERM TEMPS AND DEWPTS. ALL OTHER PREVIOUS FORECAST DETAILS REMAIN ON TRACK. AS OF 400 AM EDT WEDNESDAY... TEMPERATURES WERE UNSEASONABLY WARM FROM THE SURFACE THROUGH MID LEVELS OF THE ATMOSPHERE. 00Z/850MB TEMPERATURES WERE +20C AT BLACKSBURG TUESDAY EVENING AND ARE EXPECTED TO BE AT LEAST THAT WARM AGAIN TODAY. 700MB TEMPERATURES WILL REMAIN IN THE +8 TO +10 RANGE. WITH THAT POCKET OF MID LEVEL WARM AIR ACROSS THE OHIO VALLEY INTO NORTHERN VIRGINIA...THE BETTER PROBABILITY OF THUNDERSTORMS WILL AGAIN BE IN THE SOUTHERN PART OF THE FORECAST AREA THIS AFTERNOON AND EVENING. OVERALL SYNOPTIC PATTERN HAS FORECAST AREA UNDER A 591DM RIDGE WITH NO TRIGGERS FOR SHOWERS AND THUNDERSTORMS. THIS MEANS WEAK LEE SURFACE TROF AND OROGRAPHICS WILL AGAIN BE THE DOMINANT FORCING FOR SHOWERS AND THUNDERSTORMS AGAIN THIS AFTERNOON AND EVENING. EXPECTING BEST COVERAGE OF STORMS TO BE SIMILAR TO TUESDAY. BUFKIT SHOWED THE CAP BREAKING AND SOUNDINGS REACHING CONVECTIVE TEMPERATURE AROUND 18Z/2PM THIS AFTERNOON. CAPES WILL REACH ABOUT 2000 TO 2500 J/KG. USED WARMER MET GUIDANCE AS BASIS FOR MAXIMUM TEMPERATURES TODAY AND MINIMUM TEMPERATURES TONIGHT. THIS IS THE BEST CHANCE WE HAVE SEEN SO FAR THIS SEASON FOR A LEMONADE DAY IN BLUEFIELD WV. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 330 AM EDT WEDNESDAY... AN UPPER LEVEL TROUGH MOVES EAST INTO NEW ENGLAND THURSDAY AND PUSHES INTO THE ATLANTIC OCEAN BY FRIDAY NIGHT. THE UPPER ANTICYCLONE RETROGRADES WESTWARD AND THIS WILL ALLOW A WAVY BACKDOOR COLD FRONT TO MAKE A RUN AT OUR AREA. OVERALL...EXPECT GOOD COVERAGE OF SHOWERS AND THUNDERSTORMS DURING THIS TIME FRAME. THE ADDED CONCERNS ARE WHETHER ANY REMNANT MCV TRACK EAST SOUTHEAST TOWARD OUR FORECAST AREA. MOISTURE WILL BE INCREASING WITH PW VALUES RISING FROM 1.16 INCHES ON 00Z/17TH RNK RAOB TO AROUND 1.75 INCHES. WITH SOME HEATING...WE COULD GENERATE SOME BETTER INSTABILITY. THE RESULT SHOULD BE SLOW-MOVING WET STORM CLUSTERS CAPABLE OF PRODUCING HAIL AND VERY HEAVY RAINFALL. TEMPERATURES WILL REMAIN ABOVE NORMAL FOR THIS PERIOD WITH HIGHS FROM THE LOWER 80S IN THE MOUNTAINS TO THE MID 90S IN THE PIEDMONT. LOW TEMPERATURES WILL GENERAL BE IN THE 60S. && .LONG TERM /SATURDAY THROUGH TUESDAY/... AS OF 245 PM EDT TUESDAY... FOR SAT THROUGH SUN NIGHT: WE STAY IN A GENTLY CYCLONIC BUT LIGHT NORTHWESTERLY MID LEVEL FLOW... ON THE SOUTHWEST SIDE OF THE LARGE VORTEX WOBBLING OVER THE CANADIAN MARITIMES. THE COMPACT MID LEVEL LOW EXPECTED TO TRACK ROUGHLY EASTWARD NEAR THE CENTRAL US/CANADA BORDER LATE IN THE WORK WEEK WILL WEAKEN AND GRADUALLY SHEAR AS IT CROSSES THE UPPER MIDWEST OVER THE WEEKEND (WITH VARYING SPEEDS AMONG THE MODELS SOLUTIONS). PROPELLED BY ENERGY ROTATING AROUND THE SOUTH SIDE OF THE EASTERN CANADA VORTEX... THE SURFACE BACKDOOR FRONTAL ZONE IS EXPECTED TO DIP A BIT FURTHER SOUTHWEST TOWARD THE CWA OVER THE WEEKEND... HOLDING TO OUR NE BUT CLOSE ENOUGH TO PROVIDE A PATH FOR MID LEVEL PERTURBATIONS TO TRAVERSE THE REGION... SPAWNING GOOD COVERAGE OF SHOWERS AND STORMS... WITH GREATEST COVERAGE FOCUSED DURING (BUT NOT LIMITED TO) THE TYPICAL DIURNAL TIME WINDOWS. THE GFS AND ECMWF INDICATE THAT THE HIGHEST SHOWERS/STORM CHANCES WILL BE SAT MIDDAY THROUGH AFTERNOON. THICKNESSES REMAIN 5-15 M ABOVE NORMAL... SO WILL HOLD ONTO HIGHS IN THE 80S TO LOWER 90S... WITH CONFIDENCE REDUCED BY POTENTIAL EARLY- DAY CONVECTION LIMITING HEATING ESPECIALLY ON SAT. FOR MON/TUE: MORE OF THE SAME... WITH A SLOW WNW FLOW PATTERN WITH WEAK IMPULSES TRACKING ROUGHLY EASTWARD ACROSS THE CWA (BETWEEN THE MARITIME VORTEX RETREATING NORTHWARD AND THE BUILDING RIDGE OVER AND JUST OFF THE SOUTHEAST COAST)... SOUTH OF AN INCREASINGLY DIFFUSE FRONTAL ZONE JUST NORTH OF THE OH VALLEY. EXPECT A CONTINUED THREAT OF SCATTERED SLOW-MOVING SHOWERS AND STORMS... AGAIN PRIMARILY (BUT NOT ONLY) OCCURRING DURING THE AFTERNOON INTO EARLY EVENING. THE GFS REMAINS THE STRONGEST WITH THE UPPER-MIDWEST WAVE AS IT CROSSES MI... PLACING THE CWA IN A BIT STRONGER MID LEVEL FLOW WITH GREATER MOISTURE POOLING SOUTH OF THE FRONTAL ZONE AND THUS MUCH GREATER COVERAGE OF SHOWERS/STORMS. LEANED POPS TOWARDS GFS FOR TUESDAY WITH MENTION OF LIKELY. THIS PATTERN FAVORS TEMPERATURES CONTINUING SLIGHTLY ABOVE NORMAL. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... AS OF 140 PM EDT WEDNESDAY... ISOLATED CONVECTION EXPECTED AGAIN THIS AFTERNOON...WITH MOST FAVORED LOCATIONS BEING SRN WV/SW VA INTO SOUTHSIDE VA. FOR TAFS...HAVE VCTS IN AT BLF/BCB/ROA AND DAN. THINK CONVECTION WANES EARLY EVENING. MAINLY LOOKING AT VFR SCT TO BKN CU/TCU WITH SOME CBS. TONIGHT...SYSTEM UPSTREAM OVER NRN IL/INDIANA MAY SPILL MORE CLOUDS TOWARD THE MTNS BY DAWN WHICH COULD PRECLUDE ANY FOG FORMATION...THEREFORE LEFT FOG OUT OF LWB. THINK BCB WILL SEE A PERIOD OF MVFR VSBYS AROUND 09-12Z...BEFORE CLOUDS MOVE IN. THURSDAY MORNING...THINK SHRA/TSRA WILL BE CLOSING IN ON SE WV SO ADDED VCTS BACK IN AT LWB/BLF AROUND 15Z. EXTENDED AVIATION DISCUSSION... A BACKDOOR FRONT DIPS SOUTH TOWARD THE AREA FROM THE MASON-DIXON LINE THURSDAY AFTERNOON WHICH WILL INCREASE THE RANGE OF STORMS INTO MORE SCATTERED AND MULTICELLULAR AS OPPOSED TO PULSE. THE FRONT IS EXPECTED TO PRODUCE BETTER COVERAGE THROUGH THU NIGHT AND POTENTIALLY INTO FRIDAY. A WEAK FLOW PATTERN HOLDING OVER THE WEEKEND WILL KEEP THE STORM CHANCES EACH AFTERNOON THROUGH EARLY EVENING SAT/SUN. AREAS OF IFR FOG REMAIN POSSIBLE EACH LATE NIGHT/EARLY MORNING... PARTICULARLY IN AREAS THAT SEE RAIN THE PREVIOUS AFTERNOON. THE MOST OPTIMAL FLIGHT CONDITIONS EACH DAY SHOULD BE IN THE MID TO LATE MORNING AFTER FOG/LOW CLOUDS LIFT AND BURN OFF...AND BEFORE AFTERNOON CONVECTION REDEVELOPS. && .CLIMATE... AS OF 420 AM EDT TUESDAY... LOCATIONS RECORD HIGHS TODAY (6/18) ROANOKE 97/1925 LYNCHBURG 96/1944 DANVILLE 96/2007 BLACKSBURG 88/2007 BLUEFIELD 90/2007 LEWISBURG 88/2007 && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...AMS NEAR TERM...AMS/CF SHORT TERM...KK LONG TERM...KK AVIATION...AMS/PM/WP CLIMATE...AMS/JH
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1219 PM EDT WED JUN 18 2014 .SYNOPSIS... HIGH PRESSURE COVERED MUCH OF THE SOUTHEAST UNITED STATES TODAY. A COLD EXTENDED FROM NEW YORK INTO WISCONSIN. THIS FRONT WILL MOVE SOUTH THROUGH THE OHIO VALLEY AND MID ATLANTIC REGION ON THURSDAY...THEN STALL OVER THE AREA THROUGH THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1200 PM EDT WEDNESDAY... INCREASED THE POPS SLIGHTLY ACROSS THE SOUTHWEST AS ISOLATED THUNDERSTORMS ARE BEGINNING TO POP UP ACROSS RUSSELL COUNTY AND FURTHER BACK ACROSS PIKE COUNTY. HRRR 12Z RUN CONTINUES TO FAVOR SOME DEVELOPMENT ACROSS THE SOUTHWEST AND EAST OF THE BLUE RIDGE ACROSS SOUTHSIDE AND THE PIEDMONT LATER THIS AFTERNOON AND EVENING. WITH SURFACE TEMPS IN THE LOW 90S THIS AFTERNOON AND MU CAPES AROUND 2000 J/KG THE POSSIBILITY WILL EXIST FOR SOME ISOLATED SEVERE STORMS ONCE AGAIN TODAY. LARGE HAIL WOULD BE THE PRIMARY THREAT. STORM MOTION OF 10 KTS IS ONLY SLIGHTLY FASTER THAN YESTERDAY...SO SLOW MOVING STORMS WILL HAVE TO BE WATCHED FOR POSSIBLE FLOODING ESPECIALLY IF ANY STORM CROSSES AN AREA THAT RECEIVED DECENT RAINFALL YESTERDAY. AS OF 840 AM EDT WEDNESDAY... REMOVED FOG FROM THE GRIDS AS DAYTIME HEATING HAS QUICKLY ERODED THE PATCHY FOG THAT WAS STILL HANGING AROUND. ALSO TWEAKED THE NEAR TERM TEMPS AND DEWPTS. ALL OTHER PREVIOUS FORECAST DETAILS REMAIN ON TRACK. AS OF 400 AM EDT WEDNESDAY... TEMPERATURES WERE UNSEASONABLY WARM FROM THE SURFACE THROUGH MID LEVELS OF THE ATMOSPHERE. 00Z/850MB TEMPERATURES WERE +20C AT BLACKSBURG TUESDAY EVENING AND ARE EXPECTED TO BE AT LEAST THAT WARM AGAIN TODAY. 700MB TEMPERATURES WILL REMAIN IN THE +8 TO +10 RANGE. WITH THAT POCKET OF MID LEVEL WARM AIR ACROSS THE OHIO VALLEY INTO NORTHERN VIRGINIA...THE BETTER PROBABILITY OF THUNDERSTORMS WILL AGAIN BE IN THE SOUTHERN PART OF THE FORECAST AREA THIS AFTERNOON AND EVENING. OVERALL SYNOPTIC PATTERN HAS FORECAST AREA UNDER A 591DM RIDGE WITH NO TRIGGERS FOR SHOWERS AND THUNDERSTORMS. THIS MEANS WEAK LEE SURFACE TROF AND OROGRAPHICS WILL AGAIN BE THE DOMINANT FORCING FOR SHOWERS AND THUNDERSTORMS AGAIN THIS AFTERNOON AND EVENING. EXPECTING BEST COVERAGE OF STORMS TO BE SIMILAR TO TUESDAY. BUFKIT SHOWED THE CAP BREAKING AND SOUNDINGS REACHING CONVECTIVE TEMPERATURE AROUND 18Z/2PM THIS AFTERNOON. CAPES WILL REACH ABOUT 2000 TO 2500 J/KG. USED WARMER MET GUIDANCE AS BASIS FOR MAXIMUM TEMPERATURES TODAY AND MINIMUM TEMPERATURES TONIGHT. THIS IS THE BEST CHANCE WE HAVE SEEN SO FAR THIS SEASON FOR A LEMONADE DAY IN BLUEFIELD WV. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 330 AM EDT WEDNESDAY... AN UPPER LEVEL TROUGH MOVES EAST INTO NEW ENGLAND THURSDAY AND PUSHES INTO THE ATLANTIC OCEAN BY FRIDAY NIGHT. THE UPPER ANTICYCLONE RETROGRADES WESTWARD AND THIS WILL ALLOW A WAVY BACKDOOR COLD FRONT TO MAKE A RUN AT OUR AREA. OVERALL...EXPECT GOOD COVERAGE OF SHOWERS AND THUNDERSTORMS DURING THIS TIME FRAME. THE ADDED CONCERNS ARE WHETHER ANY REMNANT MCV TRACK EAST SOUTHEAST TOWARD OUR FORECAST AREA. MOISTURE WILL BE INCREASING WITH PW VALUES RISING FROM 1.16 INCHES ON 00Z/17TH RNK RAOB TO AROUND 1.75 INCHES. WITH SOME HEATING...WE COULD GENERATE SOME BETTER INSTABILITY. THE RESULT SHOULD BE SLOW-MOVING WET STORM CLUSTERS CAPABLE OF PRODUCING HAIL AND VERY HEAVY RAINFALL. TEMPERATURES WILL REMAIN ABOVE NORMAL FOR THIS PERIOD WITH HIGHS FROM THE LOWER 80S IN THE MOUNTAINS TO THE MID 90S IN THE PIEDMONT. LOW TEMPERATURES WILL GENERAL BE IN THE 60S. && .LONG TERM /SATURDAY THROUGH TUESDAY/... AS OF 245 PM EDT TUESDAY... FOR SAT THROUGH SUN NIGHT: WE STAY IN A GENTLY CYCLONIC BUT LIGHT NORTHWESTERLY MID LEVEL FLOW... ON THE SOUTHWEST SIDE OF THE LARGE VORTEX WOBBLING OVER THE CANADIAN MARITIMES. THE COMPACT MID LEVEL LOW EXPECTED TO TRACK ROUGHLY EASTWARD NEAR THE CENTRAL US/CANADA BORDER LATE IN THE WORK WEEK WILL WEAKEN AND GRADUALLY SHEAR AS IT CROSSES THE UPPER MIDWEST OVER THE WEEKEND (WITH VARYING SPEEDS AMONG THE MODELS SOLUTIONS). PROPELLED BY ENERGY ROTATING AROUND THE SOUTH SIDE OF THE EASTERN CANADA VORTEX... THE SURFACE BACKDOOR FRONTAL ZONE IS EXPECTED TO DIP A BIT FURTHER SOUTHWEST TOWARD THE CWA OVER THE WEEKEND... HOLDING TO OUR NE BUT CLOSE ENOUGH TO PROVIDE A PATH FOR MID LEVEL PERTURBATIONS TO TRAVERSE THE REGION... SPAWNING GOOD COVERAGE OF SHOWERS AND STORMS... WITH GREATEST COVERAGE FOCUSED DURING (BUT NOT LIMITED TO) THE TYPICAL DIURNAL TIME WINDOWS. THE GFS AND ECMWF INDICATE THAT THE HIGHEST SHOWERS/STORM CHANCES WILL BE SAT MIDDAY THROUGH AFTERNOON. THICKNESSES REMAIN 5-15 M ABOVE NORMAL... SO WILL HOLD ONTO HIGHS IN THE 80S TO LOWER 90S... WITH CONFIDENCE REDUCED BY POTENTIAL EARLY- DAY CONVECTION LIMITING HEATING ESPECIALLY ON SAT. FOR MON/TUE: MORE OF THE SAME... WITH A SLOW WNW FLOW PATTERN WITH WEAK IMPULSES TRACKING ROUGHLY EASTWARD ACROSS THE CWA (BETWEEN THE MARITIME VORTEX RETREATING NORTHWARD AND THE BUILDING RIDGE OVER AND JUST OFF THE SOUTHEAST COAST)... SOUTH OF AN INCREASINGLY DIFFUSE FRONTAL ZONE JUST NORTH OF THE OH VALLEY. EXPECT A CONTINUED THREAT OF SCATTERED SLOW-MOVING SHOWERS AND STORMS... AGAIN PRIMARILY (BUT NOT ONLY) OCCURRING DURING THE AFTERNOON INTO EARLY EVENING. THE GFS REMAINS THE STRONGEST WITH THE UPPER-MIDWEST WAVE AS IT CROSSES MI... PLACING THE CWA IN A BIT STRONGER MID LEVEL FLOW WITH GREATER MOISTURE POOLING SOUTH OF THE FRONTAL ZONE AND THUS MUCH GREATER COVERAGE OF SHOWERS/STORMS. LEANED POPS TOWARDS GFS FOR TUESDAY WITH MENTION OF LIKELY. THIS PATTERN FAVORS TEMPERATURES CONTINUING SLIGHTLY ABOVE NORMAL. && .AVIATION /16Z WEDNESDAY THROUGH SUNDAY/... AS OF 730 AM EDT WEDNESDAY... SATELLITE PICTURES SHOWED PATCHY FOG ALONG THE GREENBRIER RIVER THIS MORNING. THE VFR FOG AT KLWB WILL ERODE SHORTLY AFTER THE BEGINNING OF THE 12Z TAF PERIOD. EXPECT STORMS WILL DEVELOP ALONG BLUE RIDGE AND IN ADJACENT FOOTHILLS SOUTH OF ROANOKE THIS AFTERNOON. HARD TO PLACE EXACT TRACK OF THE ISOLATED STORMS SO WILL STICK WITH VCTS MENTIONS DURING THE MID TO LATE AFTERNOON. LOCALIZED IFR CONDITIONS WILL BE IN/NEAR STORMS AFTER 19Z/3PM WEDNESDAY. LOW CONFIDENCE FOR FOG DEVELOPMENT AGAIN TONIGHT. HAVE LEFT FOG OUT OF THE TAFS FOR NOW UNTIL WE KNOW WHICH AIRPORTS GET RAIN THIS AFTERNOON. EXTENDED AVIATION DISCUSSION... A TYPICAL SUMMER PATTERN IS ANTICIPATED THROUGH THE UPCOMING WEEKEND... WITH THE GREATEST AVIATION THREATS BEING THE SCATTERED DAYTIME CONVECTION AND THE ATTENDANT STRONG VARIABLE/GUSTY WINDS AND POSSIBLE HAIL. A BACKDOOR FRONT DIPS SOUTH TOWARD THE AREA FROM THE MASON-DIXON LINE. THE FRONT IS EXPECTED TO PRODUCE BETTER COVERAGE OF STORMS THURSDAY AFTERNOON LASTING THROUGH THU NIGHT AND POTENTIALLY INTO FRIDAY. A WEAK FLOW PATTERN HOLDING OVER THE WEEKEND WILL KEEP THE STORM CHANCES EACH AFTERNOON THROUGH EARLY EVENING SAT/SUN. AREAS OF IFR FOG REMAIN POSSIBLE EACH LATE NIGHT/EARLY MORNING... PARTICULARLY IN AREAS THAT SEE RAIN THE PREVIOUS AFTERNOON. THE MOST OPTIMAL FLIGHT CONDITIONS EACH DAY SHOULD BE IN THE MID TO LATE MORNING AFTER FOG/LOW CLOUDS LIFT AND BURN OFF...AND BEFORE AFTERNOON CONVECTION REDEVELOPS. && .CLIMATE... AS OF 420 AM EDT TUESDAY... LOCATIONS RECORD HIGHS TODAY (6/18) ROANOKE 97/1925 LYNCHBURG 96/1944 DANVILLE 96/2007 BLACKSBURG 88/2007 BLUEFIELD 90/2007 LEWISBURG 88/2007 && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...AMS NEAR TERM...AMS/CF SHORT TERM...KK LONG TERM...KK AVIATION...AMS/PM CLIMATE...AMS/JH
YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML

Area Forecast Discussion National Weather Service Spokane WA 438 AM PDT WED JUN 18 2014 .SYNOPSIS... Light rain will continue over the Idaho Panhandle and extreme eastern Washington through this morning. A drying trend will begin this afternoon with only a few lingering showers over the Panhandle tonight. Warmer...drier and more summer-like conditions will envelop the region for the rest of the week with a small chance of afternoon thunderstorms mainly over the mountains through the weekend. && .DISCUSSION... Wednesday: A deep low pressure system currently spinning over southwestern Montana will begin to track east this afternoon. The steady stream of moisture and vort max`s wrapping around its backside will finally get pulled east of the ID/MT border and rain will come to an end today following almost 24-30 hours of straight rainfall. This will be a rather slow drying trend with steady rain likely to linger through much of the morning before giving way to scattered light showers during the afternoon hours. 2AM radar and satellite confirms two last vorticity maximums will pass through the Inland NW before the storm system drifts east. One is driving moderate rains across SE WA while a second is making its way into Nrn ID from NW Montana. Timing utilizing the HRRR and satellite extrapolation suggest steady rain will end in the north (NE WA/Nrn ID) around 8AM and south (Palouse, Blues, L-C Valley, Camas Prairie) roughly 11AM. Confidence is not as high for the Central Panhandle Mtns of ID, especially along the immediate MT border which looks be clipped by one last wave of moisture during the afternoon hours. As the steady precipitation ends, sunbreaks will help destabilize the atmosphere promoting a renewed threat for showers. 500mb warming suggest any convection will be shallow but given the saturated boundary layer now in place, it even shallow convection could yield another tenth of an inch. May even get a stray thunderstorm across the northeastern mountains. Weak high pressure will begin building into the region Wednesday night and continue on Thursday. There is a good possibility that fog forms in the northeastern valleys of WA and Nrn ID after these soaking rains but coverage is still somewhat uncertain due to a light push of w/sw winds behind today`s storm system and possibility for lingering cloud cover. Spring will return to the Inland NW on Thursday under the shortwave ridging. There should be a good deal of sunshine in the morning giving way to fair afternoon cumulus and temperatures will return to seasonal normals. /sb Thursday night through Sunday...Model agreement is decent and consistent in placing the forecast area in a sustained southwest flow regime under the southeast flank of a stationary Gulf of Alaska closed low. This pattern typically argues for generally dry conditions in the basin with a small chance of afternoon and evening thunderstorms over the mountains north and east of the basin. There do not appear to be any significant waves or disturbances forecast as of yet that would bring a chance of more widespread thunderstorms during this period. Confidence is high that a warming trend will occur during this period...but not too warm since the southwest flow has a significant westerly component to shunt the hot air mass to the south of the region off to the east rather than pumping it northward into the forecast area. All in all a rather benign early summer weather regime is expected from Thursday through Sunday with a small chance of mountain thunderstorms especially in the Blues and Idaho Panhandle. /Fugazzi Sunday night through Tuesday night: Region remains in southwesterly flow throughout the period allowing for increased moisture to make it into the region. Along with the moisture, warm air will also accompany the flow bringing temps well above normal throughout the early part of the week. Weak waves of energy will pass through from SW to NE, but with limited forcing from any significant features mountain showers and isolated t-storms look to remain the extent of precip chances. The most notable feature comes through Tuesday, but even this currently is tough to get excited about as it is lacking overall dynamics. Even with models showing precipitable water values near an inch, without the trigger for showers the forecast currently looks pretty dry for most. For valley locations, the most likely changes noticed from the passing waves will be increased mid and high level clouds with maybe a stray shower. The most significant feature from the SW flow will be the warm temperatures. Monday currently looks to be the warmest with valley highs in the mid 80s to lower 90s. Even with a slight cool down on Tuesday, highs still remain 5 or so degrees above normal. /Fliehman && .AVIATION... 12z TAFS: Steady rain will remain over Ern WA and Nrn ID through 16z then gradual taper off from north to south. Light southwesterly flow will enhance mixing and allow IFR/MVFR cigs to raise and gradually scatter aft 20z. Surface heating will provide enough shallow instability to renew the threat for light showers with the highest PoPs over the higher terrain north of KGEG- KCOE. VFR conditions will return to all terminals by Wednesday afternoon/evening and persist through 12z. Fog expected to develop across the northeastern valleys and could come vcnty KSFF but confidence too low to include in TAF. /sb && .PRELIMINARY POINT TEMPS/POPS... Spokane 65 49 76 52 79 54 / 60 10 0 0 0 10 Coeur d`Alene 62 47 74 49 78 51 / 60 20 0 0 0 10 Pullman 65 45 74 47 78 49 / 100 10 0 0 0 10 Lewiston 71 52 83 55 87 57 / 100 10 0 0 10 10 Colville 69 49 78 49 80 49 / 40 20 0 0 10 0 Sandpoint 60 45 73 45 77 48 / 50 30 10 0 10 0 Kellogg 59 46 72 48 76 52 / 100 30 10 0 10 20 Moses Lake 79 53 84 56 86 55 / 10 0 0 0 0 10 Wenatchee 81 57 84 60 86 57 / 10 0 0 0 0 10 Omak 81 52 86 54 84 52 / 10 0 0 10 10 10 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
326 PM CDT WED JUN 18 2014 .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 325 PM CDT WED JUN 18 2014 MAIN FORECAST CONCERNS IS HEAVY RAIN POTENTIAL TONIGHT INTO THURSDAY MORNING. LATEST WATER VAPOR SATELLITE IMAGERY SHOWING UPPER LEVEL LOW OVER THE NORTHERN ROCKY MOUNTAINS AND WEAK SHORTWAVE TROUGHS EMBEDDED IN THE SOUTHWESTERLY FLOW ALOFT OVER THE CENTRAL UNITED STATES. LATEST 19Z SURFACE ANALYSIS INDICATES WARM FRONT/RESIDUAL OUTFLOW BOUNDARY EXTENDING FROM SOUTHEAST SOUTH DAKOTA INTO SOUTHERN IOWA. TONIGHT INTO THURSDAY...THE LATEST 18.12Z GFS/NAM INDICATE MOISTURE TRANSPORT AND CONVERGENCE TO INCREASE AFTER 00Z THURSDAY WEST OF THE FORECAST AREA AND SHIFT THE NOSE OF THE MOISTURE TRANSPORT AND CONVERGENCE INTO FORECAST AREA BY 06Z THURSDAY. WITH SUBTLE WEAK SHORTWAVE TROUGHS EJECTING OUT OF THE HIGH PLAINS INTO THE UPPER MIDWEST...EXPECT ANOTHER MCS TO FORM AND MOVE CLOSE TO THE FORECAST AREA AFTER 03-06Z THURSDAY TIMEFRAME. HOWEVER...THE EXACT LOCATION OF WHERE THE MCS WILL FORM IS STILL UNCERTAIN AND WILL HAVE AN IMPACT WHERE HEAVY RAIN WILL FALL OVER FORECAST AREA. THE 18.12Z GFS/NAM AND 15Z RAP CONTINUE TO SHOW PRECIPITABLE WATER VALUES OF 1.5-2 INCHES ACROSS FORECAST AREA AND WARM CLOUD DEPTH EXTENDING UP TO 4KM PER BUFKIT SOUNDINGS ACROSS FORECAST AREA. ANY SHOWERS/THUNDERSTORM DEVELOPMENT OVER FORECAST AREA WILL BE EFFICIENT RAIN PRODUCERS AND PRODUCE LOCAL HEAVY RAIN. THE 18.12Z GFS/NAM SUGGEST WEAK SURFACE COLD FRONT TO MOVE ACROSS THE FORECAST AREA LATE THURSDAY AFTERNOON. THE MODELS INDICATE ENOUGH MOISTURE CONVERGENCE ALONG THE FRONT TO PRODUCE ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS AND TRACK ACROSS FORECAST AREA THURSDAY AFTERNOON AND EVENING. NEXT CONCERN TONIGHT INTO THURSDAY IS SEVERE POTENTIAL...THE 18.12Z GFS/NAM INDICATE MAINLY ELEVATED INSTABILITY PER BUFKIT SOUNDINGS AND 0-3KM SHEAR IN THE 25 TO 30 KNOTS RANGE ACROSS FORECAST AREA. THE MODELS SUGGEST ALL SHEAR IN THE 0-3KM LAYER...AS THE 0-6KM SHEAR SHOWS ABOUT 30 TO 35 KNOTS. AT THIS TIME...LOOKING AT DAMAGING WINDS...LARGE HAIL AND FLASH FLOODING FROM HEAVY RAINFALL THE MAIN THREATS MAINLY SOUTH OF INTERSTATE 94. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 325 PM CDT WED JUN 18 2014 WEST TO EAST ZONAL FLOW DEVELOPS ACROSS THE NORTHERN TIER STATES FRIDAY AND SATURDAY. THE 18.12Z GFS/NAM SHOW WEAK IMPULSES EMBEDDED IN THE FLOW WITH ENOUGH MOISTURE CONVERGENCE AND LIFT IN ASSOCIATION WITH EACH IMPULSE...SHOULD ALLOW THE POSSIBILITY OF SHOWERS AND THUNDERSTORMS ACROSS FORECAST AREA. SATURDAY NIGHT THROUGH WEDNESDAY...MAIN FORECAST CONCERNS ARE PRECIPITATION CHANCES THROUGH THE PERIOD. THE 18.12Z GFS/ECMWF/GEM ARE IN GOOD AGREEMENT IN DIGGING UPPER LEVEL TROUGH OVER THE GREAT LAKES REGION EARLY NEXT WEEK. SIGNIFICANT DIFFERENCES ARE INDICATED BETWEEN THE MODELS WITH TIMING OF SHORTWAVE TROUGHS EMBEDDED IN THE WEST TO EAST ZONAL FLOW SATURDAY NIGHT INTO SUNDAY AND THE STRENGTH OF THE UPPER LEVEL TROUGH DIGGING OVER THE GREAT LAKES REGION EARLY NEXT WEEK. THIS WILL HAVE IMPACTS ON TIMING OF MOISTURE RETURN/PRECIPITATION CHANCES INTO THE FORECAST AREA SUNDAY INTO MONDAY. NEXT CONCERN ARE TEMPERATURES FOR MIDDLE OF NEXT WEEK. WITH THE 18.12Z GFS/ECMWF DIFFERING SLIGHTLY ON STRENGTH OF UPPER LEVEL TROUGH OVER THE GREAT LAKES REGION...THE 18.12Z GFS/ECMWF DIFFER ON HOW COOL AIRMASS WILL BE OVER THE FORECAST AREA...WITH THE 18.12Z ECMWF ADVECTING IN SLIGHTLY COOLER TEMPERATURES THAN THE 18.12Z GFS. THE 18.12Z ECMWF SHOWING 850MB TEMPERATURES PLUS 10 TO PLUS 12 DEGREES CELSIUS OVER FORECAST AREA...COMPARED TO PLUS 12 TO PLUS 14 DEGREES CELSIUS 850MB TEMPERATURES BY THE 18.12Z GFS. TEMPERATURES OVER FORECAST AREA BY MIDDLE OF NEXT WEEK LOOK TO BE UNSEASONABLY COOL. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 1240 PM CDT WED JUN 18 2014 GENERALLY VFR CONDITIONS TO PREVAIL OUTSIDE OF CONVECTIVE SYSTEMS...WHICH REMAIN SOMEWHAT TROUBLE TO NAIL DOWN. IN WAKE OF OVERNIGHT SYSTEM...EXPECT QUIET PERIOD THROUGH MUCH OF TODAY BUT WITH WARM FRONT BOUNDARY STILL IN AREA AND LOW LEVEL JET SETTING UP AGAIN TONIGHT...COULD SEE REPEAT PERFORMANCE WITH MAINLY LATE NIGHT STORMS AGAIN. BETTER FORCING AND MOISTURE TRANSPORT SEEMS FURTHER WEST AND SOUTH TONIGHT SO UNSURE OF INTENSITY BUT LEANED ON LATE NIGHT CONVECTION AND TRIED TO NARROW DOWN A SMALL TIME WINDOW FOR BRUNT OF STORMS/LOWEST AVIATION CATEGORIES. CONVECTION SHOULD CLEAR OUT THURSDAY MORNING SO RETURN TO VFR. && .HYDROLOGY... ISSUED AT 325 PM CDT WED JUN 18 2014 THE FORECAST AREA REMAINS IN A VERY MOIST AND UNSTABLE AIRMASS THROUGH THURSDAY EVENING WITH PRECIPITABLE WATER VALUES IN THE 1.5 TO 2 INCH RANGE AND WARM CLOUD DEPTHS UP TO 4 KM. THE COMBINATION OF ANOTHER ROUND OF CONVECTION TO IMPACT THE FORECAST AREA TONIGHT AND RECENT HEAVY RAINFALL THE LAST COUPLE OF DAYS...WILL CONTINUE WITH THE FLASH FLOOD WATCH FOR SOUTHEAST MINNESOTA...NORTHEAST IOWA...SOUTHWEST AND CENTRAL WISCONSIN THROUGH THURSDAY MORNING. ALSO...DUE TO THE RECENT HEAVY RAINFALL...THE CEDAR...TREMPEALEAU AND BLACK RIVERS HAVE RISEN OR ARE FORECASTED TO RISE ABOVE FLOOD STAGE AND FLOOD WARNINGS ARE IN EFFECT PORTIONS OF THESE RIVERS. SEE THE LATEST FLOOD STATEMENTS FOR EXACT FORECAST DETAILS. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR WIZ032>034- 041>044-053>055-061. MN...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR MNZ079-086>088- 094>096. IA...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR IAZ008>011-018- 019-029-030. && $$ SHORT TERM...DTJ LONG TERM...DTJ AVIATION...TJS HYDROLOGY...DTJ
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE

.SHORT TERM...TONIGHT AND THURSDAY ISSUED AT 234 PM CDT WED JUN 18 2014 THE LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW THE REMNANTS OF AN MCV MOVING EAST ACROSS NORTHEAST WISCONSIN EARLY THIS AFTERNOON. MOST OF THE RAIN HAS EXITED THE REGION EXCEPT FOR A FEW SPOTTY SHOWERS OVER EAST-CENTRAL WISCONSIN. CONVECTIVE OUTFLOW BOUNDARY HAS SHIFTED SOUTH INTO CENTRAL ILLINOIS AND CENTRAL IOWA...BUT A BAND OF CLOUDS FROM SOUTHERN WISCONSIN TO CENTRAL MINNESOTA MARKS WHERE THE 850MB FRONT IS LOCATED. AREAS IN PROXIMITY OF THESE BOUNDARIES ARE MOSTLY DRY DUE TO STRONG CAPPING OVERHEAD. FORECAST CONCERNS REVOLVE AROUND THE POSSIBILITY OF RENEWED STORM DEVELOPMENT TONIGHT AND TOMORROW. TONIGHT...MCV OVER EASTERN WISCONSIN WILL BE EXITING TO THE EAST EARLY IN THE EVENING. REMNANT 850MB BOUNDARY WILL HANG BACK HOWEVER...FROM EAST-CENTRAL OR SOUTHEAST WISCONSIN TO CENTRAL MINNESOTA BUT WILL PIVOT A BIT AS THE WESTERN END BENDS NORTHWARD. WILL HAVE WEAK LIFT ALONG THE FRONT THROUGH THE EVENING IN THE FORM OF ISENTROPIC ASCENT AND MID-LEVEL FGEN. MODELS ARE QUITE DRY THIS EVENING OVER CENTRAL WISCONSIN WHICH IS THE PART OF THE FORECAST AREA THAT WILL BE CLOSEST TO THE BOUNDARY. BUT THE CLOSE PROXIMITY OF THE FRONT TO CENTRAL WISCONSIN WILL KEEP A LOW CHANCE OF SHOWERS AND STORMS IN THE FORECAST FOR THE EVENING. AS HEIGHT FALLS ACROSS THE NORTHERN PLAINS CAUSE THE WESTERN PART OF THE FRONT TO LIFT NORTHWARD...CHANCES OF SHOWERS AND STORMS WILL SPREAD NORTHEAST A BIT OVERNIGHT. BUT UNLIKE THE LAST COUPLE NIGHTS...WILL NOT HAVE ANY UPPER LEVEL SUPPORT AND CANNOT FIND HARDLY ANY INSTABILITY. SO AM NOT THINKING A REPEAT OF LAST NIGHTS WIDESPREAD HEAVY RAIN WILL OCCUR...BUT MORE IN THE WAY OF ISOLD TO SCT SHOWERS AND STORMS. NORTHEAST WISCONSIN MAY REMAIN DRY THROUGH THE NIGHT WHERE NORTHEAST WINDS WILL BE FUNNELING STABLE AIR INTO THIS PART OF THE STATE. LOWS RANGING FROM THE MIDDLE 50S NORTHEAST TO THE MIDDLE 60S SOUTHWEST. THURSDAY...A LARGE CLOSED UPPER LOW WILL SHIFT EAST ACROSS THE NORTHWEST GREAT PLAINS...WHICH WILL HELP PUSH THE 850MB FRONT INTO NORTHEAST WISCONSIN. WILL CONTINUE TO HAVE WEAK FORCING ALONG THE FRONT ALONG WITH PWATS UPWARDS OF 1.75 INCHES. WITH SUFFICIENT DAYTIME HEATING...A 79/65 PARCEL WILL YIELD NEARLY 1000 J/KG OF ML CAPE NEAR WISCONSIN RAPIDS. 0-6KM BULK SHEARS ARE ONLY AROUND 25 KTS...AND WITH QUESTION MARKS ABOUT THE AMOUNT OF HEATING AND DEGREE OF FORCING...THINK A SEVERE THREAT IS RATHER MARGINAL. SPC KEEPS THE SLIGHT RISK OF SEVERE WEATHER OVER FAR SW WISCONSIN TOMORROW...AND THIS LOOKS GOOD. BEING NEAR THE MID-LEVEL RIDGE AXIS...ANY STORMS WILL BE SLOW MOVING AND COULD DROP QUICK HALF INCH TO INCH OF RAINFALL. BUT AM ANTICIPATING COVERAGE TO BE ONLY SCT IN NATURE DUE TO THE WEAK FORCING. WILL HAVE THE HIGHEST CHANCES OF PRECIP OVER CENTRAL WISCONSIN DURING THE AFTERNOON. HIGH TEMPS RANGING FROM THE MIDDLE 70S TO LOW 80S. .LONG TERM...THURSDAY NIGHT THROUGH WEDNESDAY ISSUED AT 234 PM CDT WED JUN 18 2014 OVERALL UPPER-LEVEL FLOW OVER THE WESTERN GREAT LAKES WILL BECOME BRIEFLY MORE ZONAL LATE IN THE WORK WEEK AS UPPER-LOW NEAR LAKE WINNEPEG HEADS EAST ACROSS SOUTHERN CANADA AND UNDERCUTS RIDGE. UNFORTUNATELY...WEAK IMPULSES EMBEDDED WITHIN THE ZONAL FLOW WILL CONTINUE TO PROVIDE OPPORTUNITIES FOR BOUTS OF PRECIPITATION INTO THE WEEKEND. UNLIKELY MODEL GUIDANCE WILL HAVE A VERY GOOD HANDLE ON THESE WEAK IMPULSES THUS FORECAST CONFIDENCE HEADING INTO THE WEEKEND IS LOW. EVENTUALLY PATTERN AMPLIFIES AGAIN OVER THE NORTHERN CONUS AS UPPER-LEVEL RIDGE AXIS TRIES TO BECOME RE- ESTABLISHED FURTHER WEST OVER CENTRAL CANADA WITH DOWNSTREAM TROUGH DIGGING SOUTHWARD OVER THE WESTERN GREAT LAKES DURING THE FIRST HALF OF NEXT WEEK. LATEST GUIDANCE ALSO SUGGESTS SOME POTENTIAL FOR WEAK DISTURBANCES TO UNDERCUT CANADIAN RIDGE AS THEY MOVE ACROSS THE NORTHERN PLAINS TOWARD THE WESTERN GREAT LAKES. BOTTOM LINE IS THAT UNSETTLED WEATTHER PATTERN WILL LIKELY PERSIST INTO THE MIDDLE OF NEXT WEEK WITH ABOVE NORMAL PRECIPTATION. THURSDAY NIGHT INTO FRIDAY APPEARS TO BE THE MOST ACTIVE PERIOD IN THE EXTENDED PORTION OF THE FORECAST AS FAIRLY ROBUST SHORTWAVE TROUGH WEST OF LAKE WINNEPEG EJECTS DISTURBANCES EASTWARD TOWARD THE AREA. THESE IMPULSES WILL PROVIDE MORE ORGANIZED LARGE- SCALE ASCENT THAT WILL ACT IN CONCERT WITH A FRONTAL BOUNDARY THAT WILL REMAIN JUST SOUTHWEST OF THE FORECAST AREA. RATHER POTENT DISTURBANCE IS FORECAST TO SWING NORTHEAST TOWARD THE UPPER MISSISSIPPI VALLEY THURSDAY EVENING. STILL MUCH UNCERTAINTY AS TO HOW CONVECTION WILL EVOLVE THURSDAY NIGHT ALONG THE MISSISSIPPI RIVER VALLEY. CONSENSUS OF MODEL GUIDANCE SEEMS TO SUGGEST TWO AREAS OF FOCUS FOR CONVECTION EARLY THURSDAY EVENING...ONE ALONG THE WARM FRONT AND GREATER INSTABILITY OVER NORTHEAST IOWA AND SOUTHWEST WISCONSIN...AND THE OTHER CLOSER TO THE STRONGER UPPER- LEVEL DYNAMICS OVER CENTRAL MINNESOTA. ALL MODELS SUGGEST CONVECTIVE ACTIVITY WILL LIKELY CONSOLIDATE OVER THE FORECAST AREA OVERNIGHT THURSDAY THEN PUSH EAST ACROSS THE AREA FRIDAY MORNING. STILL COPIOUS MOISTURE IN PLACE OVER THE FORECAST AREA...THUS ANOTHER BOUT OF FAIRLY SUBSTANTIAL RAINFALL SEEMS TO BE A GOOD BET. HOWEVER...DEEP LAYER SHEAR DOES NOT APPEAR TO BE VERY SUPPORTIVE OF WIDESPREAD SEVERE CONVECTION OVER THE FORECAST AREA THURSDAY NIGHT WITH SHEAR MORE FAVORABLE UPSTREAM OVER IOWA AND SOUTHERN MINNESOTA AND PERHAPS INTO SOUTHWEST WISCONSIN. ALTHOUGH THERE COULD BE A BREAK IN THE PRECIPITATION FRIDAY AFTERNOON...BULK OF MODEL GUIDANCE SUGGESTS ANOTHER IMPULSE TO EJECT EASTWARD ACROSS THE WESTERN GREAT LAKES SOMETIME FRIDAY NIGHT INTO SATURDAY. HOWEVER WAY TOO MUCH DISCREPANCY IN THE GUIDANCE TO TRY AND NAIL DOWN LOCATION AND TIMING...SO WILL BE FORCED TO MAINTAIN BROAD BRUSH CHANCE POPS OVER THE ENTIRE AREA FRIDAY NIGHT RIGHT ON THROUGH THE WEEKEND. && .AVIATION...FOR 18Z TAF ISSUANCE ISSUED AT 1210 PM CDT WED JUN 18 2014 SHOWERS AND THUNDERSTORMS ARE DEPARTING CENTRAL AND EASTERN WISCONSIN EARLY THIS AFTERNOON. AS THE RAIN DEPARTS SHOULD SEE CIGS GRADUALLY IMPROVE THROUGH THE REST OF THE AFTERNOON. THEN WILL SEE A WARM FRONT RETURN NORTHEAST LATE TONIGHT INTO THURSDAY MORNING WHICH HAS POTENTIAL TO BRING MVFR/IFR CIGS A CHANCE OF SHOWERS AND STORMS. THE CHANCE OF STORMS SHOULD MAINLY BE CONFINED TO CENTRAL AND NORTH-CENTRAL WISCONSIN THROUGH THE END OF THE TAF PERIOD. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....MPC LONG TERM......ESB AVIATION.......MPC