Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 06/14/12


AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1258 AM CDT TUE JUN 12 2012 .DISCUSSION... 903 PM CDT UPDATE FOR REST OF TONIGHT...LAST HOPES FOR EVEN A STRAY SHOWER OR THUNDERSHOWER FOR THE EASTERN PORTION OF THE LOCAL FORECAST AREA IS QUICKLY DRYING UP...PUN INTENDED...AS THE PRE-FRONTAL TROUGH HAS SHIFTED THE AXIS OF HIGHEST DEW POINTS AND GREATEST POTENTIAL INSTABILITY E TO SW LOWER MI AND N CENTRAL IN. THE TRUE COLD FRONT IS WELL DELINEATED FROM EXTREME SE WI SOUTHWESTWARD TO W CENTRAL IL BY BOTH A WIND SHIFT FROM SW TO W AND NW...AS WELL AS A DEW POINTS FALLING OFF TO THE UPPER AND MID 50S. CURRENT REMAINING SLIGHT CHANCE POP NUMBERS FOR THE SE PORTION OF THE FA WILL BE DROPPING OUT WITHIN AN HOUR OR TWO. WITH CHANCES OF RAIN MINIMAL AT BEST THROUGH EARLY NEXT WEEK AT LEAST...AND NEAR ZERO CHANCES THROUGH THE REST OF THIS WEEK INCREASINGLY SERIOUS SOIL MOISTURE DEFICITS WILL LIKELY BE CAUSING EVEN GREATER STRESS ON TREES AND CROPS. TRS //PREV DISCUSSION... 320 PM CDT THE FORECAST CONCERNS ARE VERY MINIMAL THROUGH THE REST OF THE WEEK WITH A CONTINUED DRY PATTERN. WILL BE MONITORING FOR A FEW STORMS LATE THIS AFTERNOON INTO EARLY EVENING...OTHERWISE THAT MAY WILL LIKELY BE ALL THAT IS ON THE SCOPE FOR QUITE A WHILE. ISOLATED SHOWERS WITH A FEW STORMS REDEVELOPING OVER COOK COUNTY AND SOUTH ALONG THE IL/IN STATE LINE...WHICH IS ALONG AND JUST AHEAD OF A WEAK CONVERGENT AXIS AND APPARENT SHORT WAVE SEEN ON SATELLITE. MID 80S TEMPERATURES AND UPPER 60S DEW POINTS ALONG AND AHEAD OF THIS CORRIDOR HAS BUILT SURFACE BASED CAPE TO AROUND OR SLIGHTLY OVER 2000 J/KG. THIS CONVECTION SHOULD LAST LONGER THAN THE PREVIOUS ACTIVITY NEAR NOON BEING CLOSER TO THE SHORT WAVE CENTER AND HAVING MORE INSTABILITY TO WORK WITH. UPPER LEVEL WIND SHEAR LOOKS TO BE AROUND A MEAGER 20 KT PER PROFILER ANALYSIS. THE BEHAVIOR OF THE STORM CORES IS LIKELY TO BE SOMEWHAT PULSY WITH INSTABILITY IN THE DRIVERS SEAT...AND WITH LIMITED ATTENDANT SHEAR IT LEAVES ONLY A VERY SMALL CHANCE FOR ANY TYPE OF SEVERE ACTIVITY. THE SYSTEM UPPER TROUGH CENTER IS LOCATED ALONG THE MN/WESTERN QUEBEC BORDER WITH PRIMARY HEIGHT FALLS...THE UPPER JET AXIS...AND ASSOCIATED DEEPER ASCENT MOVING EAST FROM THERE. THIS FORCING HAS AIDED SOME SHOWER DEVELOPMENT ALONG THE SURFACE COLD FRONT IN WESTERN WI. THE COOL FRONT EXTENDS SOUTH FROM THERE WHERE IT WILL MOVE INTO NW IL BY 4 PM AND EAST THROUGH THE FORECAST AREA THIS EVE. THE WIND SHIFT IS GRADUAL FROM WEST SOUTHWEST TO WEST NORTHWEST ALONG THE BOUNDARY...AND IT IS ACTUALLY AHEAD OF THE STRONGEST MOISTURE CONVERGENCE. SO OVERALL CONVERGENCE IS LIMITED AND FEEL THAT WILL BE THE CASE WITH ANY CONVECTION THAT WERE TO TRIGGER ALONG IT...WHICH IS NOW APPEARING DOUBTFUL IN OUR AREA. THE HRRR AND OTHER EXPLICIT CONVECTIVE MODELS AGREE IN THIS LIMITED COVERAGE. THE COOL FRONT WILL MOVE THROUGH THE AREA THIS EVENING AND IT LOOKS LIKE THE BOUNDARY LAYER WILL STAY MIXED AS IT DOES SUCH...WITH SOME GUSTS UP TO 20 MPH AS THE PRESSURE RISE AXIS MOVES THROUGH. SUNNY AND DRY WEATHER WILL THEN ONCE AGAIN BE THE STORY AS CANADIAN HIGH PRESSURE MOVES OVERHEAD TUESDAY NIGHT INTO WEDNESDAY. THE REALLY ONLY WEATHER OF INTEREST FROM DAY TO DAY WILL BE HOW LOW DEW POINTS WILL DROP DURING THE AFTERNOON MIXING...AND TO WHAT DEGREE OF COOLING WILL THERE BE FROM THE LAKE. NORTHWEST WINDS WILL BEGIN TO DECREASE TUESDAY AFTERNOON...POTENTIALLY ALLOWING FOR A SLIGHT LAKE BREEZE INTO IL...BUT LIKELY INTO IN. THIS MAY NOT DEVELOP UNTIL LATE AFTERNOON THOUGH...SO WIDESPREAD HIGHS IN THE MID TO UPPER 70S ARE EXPECTED. UPSTREAM DEW POINTS TODAY HAVE BEEN IN THE LOWER TO MID 40S ACROSS EASTERN SD. THIS AND POSSIBLY EVEN LOWER SHOULD BE REALIZED DURING TUESDAY AFTERNOON WITH PROJECTED MIXING TO 850 MB. THE AFTERNOON HUMIDITY WILL REMAIN LOW...UNDER 25 PERCENT...ON WEDNESDAY AFTERNOON WITH THE SYNOPTIC FLOW TURNING NORTHEAST AND THEN EAST. INFLUENCE FROM THE LAKE WILL LIKELY CONTINUE TO MOVE INTO CHICAGO DURING THE AFTERNOON ALL THE WAY THROUGH SATURDAY. THE UPPER LEVEL HEIGHTS AND LOW-LEVEL THERMAL RIDGE BUILD MORE INTO THE AREA THURSDAY NIGHT INTO SATURDAY. THE EC HAS SHOWN IN THE UPPER LEVEL SW FLOW THAT SHORT WAVE ENERGY IS POSSIBLE WITHIN THIS AND MAY DAMPEN THE RIDGE SLIGHTLY SATURDAY NIGHT INTO SUNDAY...AND HAVE A SMALL CHANCE FOR POPS DURING PART OF THAT TIME. OTHERWISE...HAVE COLLABORATED GOING DRIER THAN POPS AND DEW POINTS FROM GUIDANCE BLENDS IN THE EXTENDED PER PERSISTENCE AND AN OVERALL STAGNANT PATTERN. MTF && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 06Z... * NO REAL CONCERNS THIS FORECAST PERIOD WITH VFR CONDITIONS EXPECTED. * NORTHWEST WINDS WILL INCREASE THROUGH LATE MORNING WITH GUSTS INCREASING UP TO AROUND 18KT...BEFORE WINDS START TO SHIFT MORE NORTH NORTHWEST AND EVENTUALLY SHIFT COMPLETELY OVER TO THE NORTHEAST BY LATE AFTERNOON AND EARLY EVENING. RODRIGUEZ //DISCUSSION...UPDATED 06Z... AS SURFACE TROUGH AND COLD FRONT CONTINUE TO SHIFT EAST OF THE TERMINALS EARLY THIS MORNING...HIGH PRESSURE WILL BUILD EAST ACROSS THE AREA. WITH HIGH PRESSURE BUILDING IN...ANY REMAINING CLOUD COVER WILL ALSO EXIT WITH LIMITED CLOUD COVER EXPECTED FOR THE REMAINDER OF THE TAF PERIOD. WINDS HAVE SHIFTED TO THE WEST NORTHWEST EARLY THIS MORNING WITH SOME BRIEF GUSTS REPORTED. ANY GUSTS SHOULD DIMINISH OVER THE NEXT HOUR BEFORE INCREASING ONCE AGAIN BY MID MORNING. CAN EXPECT NORTHWEST GUSTS TO AROUND 18KT WITH WINDS SHIFTING ALL THE WAY TO THE NORTHEAST BY LATE THIS AFTERNOON AND EARLY EVENING. HAVE SHIFTED THE WINDS A TAD QUICKER THAN GUIDANCE WAS SHOWING...AS COULD SEE THIS QUICKER FLOP OVER TO THE NORTHEAST WITH THE LAKE INFLUENCE. RODRIGUEZ //ORD AND MDW CONFIDENCE...UPDATED 06Z... * HIGH CONFIDENCE WITH VFR CONDITIONS. * HIGH CONFIDENCE WITH WIND SPEED AND DIRECTION THROUGH EARLY AFTERNOON...WITH MEDIUM CONFIDENCE AS TO TIMING OF WIND SHIFT LATER IN THE AFTERNOON AND EARLY EVENING. RODRIGUEZ //OUTLOOK FOR ORD/MDW FOR 12Z WEDNESDAY-12Z MONDAY...UPDATED 00Z... WEDNESDAY THROUGH SUNDAY...VFR. SLIGHT CHC SHRA/TSRA WEST OF TERMINALS SUNDAY. RATZER && .MARINE... 231 PM CDT A LARGE LOW HAS MOVED INTO HUDSON BAY...WHILE HIGH PRESSURE SITS OFF THE NEW ENGLAND COAST. THE UPPER LEVEL PRESSURE GRADIENT HAS RELAXED...RESULTING IN SOUTH TO SOUTHWEST WINDS 15-25 KT ACROSS THE LAKE THIS AFTERNOON. STRONGEST WINDS AROUND 25 KT WILL CONTINUE TO BE OVER THE NORTHERN HALF OF THE LAKE WHICH IS CLOSER TO THE LOW AND ITS TIGHT PRESSURE GRADIENT. THE LOWS COLD FRONT WILL SWEEP ACROSS THE LAKE TONIGHT. WINDS WILL TURN OUT OF THE WEST AT 15 TO 25 KT ACROSS THE LAKE BEHIND THE FRONT. HIGH PRESSURE MOVES IN BEHIND THE FRONT TUESDAY NIGHT...WITH WINDS DIMINISHING AND BECOMING NORTHERLY FOR A ON TUESDAY. THE LIGHT WINDS WILL CONTINUE TO VEER TO EASTERLY AS THE HIGH MOVES OVER THE LAKE WEDNESDAY. WINDS TURN SOUTHEASTERLY AS THE HIGH MAKES ITS WAY OVER NORTHERN QUEBEC ON THURSDAY. ALTHOUGH THE CENTER OF THE HIGH MOVES OFF TO THE NORTHEAST...A LARGE RIDGE WILL REMAIN OVER THE EASTERN THIRD OF THE US THROUGH THE REMAINING PART OF THE FORECAST PERIOD. THIS PATTERN WILL RESULT IN LIGHT WINDS VARYING BETWEEN EAST AND SOUTH. JEE && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1115 PM CDT MON JUN 11 2012 .DISCUSSION... ISSUED 849 PM CDT MON JUN 11 2012 LATEST SURFACE ANALYSIS INDICATING THE COLD FRONT WAS LOCATED JUST WEST OF PEORIA AND JACKSONVILLE WITH DEW POINTS SOME 15 TO 20 DEGREES LOWER TO THE WEST OF THE FRONT EARLY THIS EVENING. EXTENSIVE CLOUD COVER FROM THE CONVECTION WHICH OCCURRED OVER PARTS OF THE CENTRAL AND SOUTHERN FORECAST AREA TODAY...AND LACK OF ANY SIGNIFICANT LOW LEVEL CONVERGENCE ALONG THE FRONT HAS LED TO VERY LITTLE REDEVELOPMENT OF STORMS THIS EVENING. THE BULK OF THE NEWLY DEVELOPED CONVECTION HAS OCCURRED FURTHER TO THE NORTH AND EAST AND WAS MOVING AWAY FROM OUR AREA. THE 00Z ILX SOUNDING INDICATING A FAIRLY WORKED OVER ATMOSPHERE ACROSS CENTRAL ILLINOIS FROM THE CONVECTION OF EARLIER TODAY WITH A SIGNIFICANT AMOUNT OF CONVECTIVE INHIBITION NOTED. THE SLIGHT CHANCE/ISOLATED POPS HAVE BEEN REMOVED FROM THE GRIDS AND OTHER THAN SOME MINOR TWEAKS TO THE EARLY EVENING HOURLY TEMPS...THE REST OF THE FORECAST HAS A GOOD HANDLE ON THE OVERNIGHT TRENDS. THE UPATED ZONE FORECAST WILL BE OUT BY 915 PM. && .AVIATION... ISSUED 1105 PM CDT MON JUN 11 2012 VFR CONDITIONS TO CONTINUE THROUGH TUESDAY NIGHT. THE COLD FRONT CONTINUES TO MAKE SLOW PROGRESS ACRS THE STATE THIS EVENING. IT WAS CURRENTLY ALONG THE I-55 CORRIDOR AND SHOULD TRACK EAST OF OUR TAF SITES BY 07Z. WINDS SHOULD SWITCH INTO THE NORTHWEST AFTR FROPA WITH SPEEDS AVERAGING FROM 5 TO 10 KTS. FORECAST SOUNDINGS FOR TUESDAY CONTINUE TO SUGGEST MAINLY CLEAR SKIES DURING THE DAY WITH PERHAPS A FEW CU AT TIMES WITH BASES AROUND 4500-5000 FEET. NORTHWEST WINDS OF 12 TO 17 KTS CAN BE EXPECTED DURING THE DAY...WITH WINDS QUICKLY DIMINISHING TOWARDS EVENING. SMITH && .PREV DISCUSSION... ISSUED 258 PM CDT MON JUN 11 2012 SHORT TERM...TONIGHT THROUGH THURSDAY MAIN QUESTION IN THE IMMEDIATE SHORT-TERM IS WHETHER OR NOT ANY CONVECTION WILL RE-DEVELOP ALONG AN ADVANCING COLD FRONT THIS EVENING. 2 PM SURFACE ANALYSIS SHOWS FRONT ACROSS EASTERN IOWA...HOWEVER AIRMASS AHEAD OF IT IS STILL QUITE STABLE DUE TO MORNING CONVECTION THAT DECAYED ACROSS WEST-CENTRAL ILLINOIS. LATEST MESO-ANALYSIS FROM SPC IS INDICATING SOME DESTABILIZATION ALONG THE BOUNDARY...WITH SURFACE-BASED CAPES BACK UP TO AROUND 1500 TO 2000J/KG. 19Z VISIBLE SATELLITE IMAGERY IS SHOWING A NARROW RIBBON OF CU DEVELOPING IN THE INSTABILITY AXIS...HOWEVER NO SHOWERS/STORMS HAVE FIRED YET. 12Z MODELS ARE LARGELY USELESS...AS NONE OF THEM ADEQUATELY PREDICTED THE STORMS THAT ROLLED ACROSS SOUTH-CENTRAL AND SOUTHEAST ILLINOIS THIS AFTERNOON ALONG THE LEADING EDGE OF AN OLD OUTFLOW BOUNDARY. EVEN SOME OF THE HIGHER-RES MODELS SUCH AS THE 4KM WRF FAILED TO CAPTURE THIS CONVECTION...SO THEIR SOLUTIONS FOR LATE THIS AFTERNOON AND EVENING ARE SUSPECT. THE 17Z HRRR SEEMS TO HAVE THE BEST HANDLE ON REALITY...SHOWING THE CURRENT CONVECTION ACROSS THE FAR E/SE KILX CWA EXITING THE AREA OVER THE NEXT 2 TO 3 HOURS...FOLLOWED BY LARGELY DRY CONDITIONS THIS EVENING. THE HRRR DOES TRY TO DEVELOP SOME ISOLATED CONVECTION ALONG THE COLD FRONT AS IT PUSHES INTO THE ILLINOIS RIVER VALLEY AROUND 00Z...BUT THIS RAPIDLY DISSIPATES AS DAYTIME INSTABILITY IS LOST AFTER SUNSET. SINCE THE FRONT IS STILL OFF TO THE WEST...THINK THIS SOLUTION SEEMS REASONABLE...SO WILL MENTION ISOLATED THUNDER ACROSS THE BOARD DURING THE EARLY EVENING. AFTER THAT...SKIES WILL CLEAR FROM WEST TO EAST ACROSS THE AREA AS THE FRONT PUSHES INTO INDIANA AFTER MIDNIGHT. HIGH PRESSURE WILL BUILD INTO THE GREAT LAKES FOR THE MIDDLE OF THE WEEK...PROVIDING COOLER AND LESS HUMID CONDITIONS FOR TUESDAY THROUGH THURSDAY. COOLEST MORNING WILL BE WEDNESDAY MORNING...WHEN TEMPS FALL INTO THE LOWER 50S. AFTERNOON HIGHS ON WEDNESDAY WILL BE NEAR OR SLIGHTLY BELOW NORMAL IN THE UPPER 70S/LOWER 80S. LONG TERM...FRIDAY THROUGH MONDAY WARMER AND MORE HUMID WEATHER WILL RETURN FOR THE EXTENDED...AS UPPER TROUGH DIGS ACROSS THE WESTERN CONUS AND RIDGING DEVELOPS ACROSS THE EAST. MODELS CONTINUE TO DISAGREE ON THE EXACT DEGREE OF AMPLIFICATION WITHIN THE FLOW...WITH THE 12Z 11 JUN GFS FEATURING A STRONG RIDGE AND RESULTING DRY CONDITIONS RIGHT THROUGH EARLY NEXT WEEK. MEANWHILE...THE LATEST ECMWF CONTINUES TO BE WEAKER WITH THE UPPER RIDGE AND BRINGS A FRONTAL BOUNDARY INTO THE AREA SUNDAY INTO MONDAY. GIVEN CURRENT MODEL DISCREPANCIES AND THE FACT THAT PARTS OF CENTRAL ILLINOIS ARE IN A MODERATE DROUGHT...WILL MAINTAIN HOT AND DRY CONDITIONS THROUGH MONDAY. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
606 PM CDT WED JUN 13 2012 ...UPDATE TO AVIATION... .SYNOPSIS... ISSUED AT 342 PM CDT WED JUN 13 2012 A BROAD WEAK, ZONAL MID LEVEL FLOW PATTERN WA IN PLACE ACROSS WESTERN KANSAS. INCREASING BOUNDARY LAYER MOISTURE WAS OCCURRING AS SOUTHERLY WINDS TRANSPORTED HIGHER CONTENT MOISTURE AIR FROM WESTERN OKLAHOMA AND THE PANHANDLES. FARTHER WEST, A DRYLINE WAS EVIDENT IN THE MESONET POINT DATA ACROSS SOUTHEAST COLORADO, AS WELL AS IN A FINE LINE DEVELOPING ON KPUX RADAR FROM LAMAR, CO SOUTHWEST. && .SHORT TERM...(THIS EVENING THROUGH TOMORROW) ISSUED AT 342 PM CDT WED JUN 13 2012 THE SHORT TERM MODELS HANDLE THE EVOLUTION OF CONVECTION THIS EVENING VERY DIFFERENTLY AND THERE IS RELATIVELY LOW CONFIDENCE IN THIS NEAR TERM FORECAST. THE 12UTC NAM MODEL WOULD INDICATE AND STORMS THAT DEVELOP REMAIN ANCHORED TO THE MUCH HIGHER CAPE/INSTABILITY AXIS OF THE HIGH PLAINS OF COLORADO INTO THE WEST TEXAS PANHANDLE THIS EVENING. AT HIS TIME, THIS NAM SOLUTION SEEMS TO BE MORE LIKELY THAN OTHERS BASED ON THE WEAK FORCING ENVIRONMENT WE ARE DEALING WITH. HOWEVER, WE CANNOT COMPLETELY IGNORE THE RECENT ARW-WRF/NMM RUNS AND HRRR THAT HAVE ELUDED TO CONVECTION OVER EASTERN COLORADO LATER THIS AFTERNOON DEVELOPING A COLD POOL AND SPREADING RAPIDLY INTO THE WESTERN SEVERAL TIERS OF COUNTIES IN THE EVENING HOURS. IF THAT DOES OCCUR, THE MOST PLAUSIBLE OUTCOME WOULD SEEM TO BE MARGINALLY ISOLATED SEVERE THUNDERSTORM WIND GUSTS AND PERHAPS ISOLATED HAIL PUSHING SEVERE LIMITS OF AN INCH AT MOST. HOWEVER, THE WEAKER CONVECTION COULD SPREAD FOR SEVERAL HOURS EASTWARD INTO CENTRAL KANSAS DURING THE LATE EVENING. CONVECTIVE CHANCES ARE JUST AS GOOD OR BETTER ALONG A STRENGTHENING COLD FRONTAL BOUNDARY WHICH SHOULD UNDERGO FRONTOGENESIS FROM WEST CENTRAL KANSAS INTO NORTH CENTRAL KANSAS DURING THE VERY LATE AFTERNOON INTO THURSDAY EVENING. THIS WILL BE BE WEAK FORCING, BUT PERHAPS MORE MODERATE CAPE VALUES BY LATE IN THE DAY. ISOLATED SEVERE CONVECTION COULD BE FOUND THROUGH THE INTERSTATE 70 CORRIDOR, WESTWARD TO SCOTT CITY LATE IN THE AFTERNOON THURSDAY, BUT WIDESPREAD SEVERE IS NOT ANTICIPATED. THE NAM MODEL IS INDICATING THE WARMEST TEMPERATURES AROUND 100 DEGREES, WHILST MOST OTHER NUMERICAL OUTPUT IS INDICATING LOW 90S. TEMPERATURES SHOULD WARM TO SOMEWHERE IN THE MIDDLE THURSDAY AFTERNOON ACROSS SOUTHWEST AND CENTRAL KANSAS. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 302 PM CDT WED JUN 13 2012 THE EXTENDED PERIOD BEGINNING FRIDAY WILL SEE ONE UPPER SHORT WAVE EXITING THE WESTERN PLAINS OF KANSAS, BRINGING ABOUT A 40 TO 50 PERCENT CHANCE OF THUNDERSTORMS NEAR THE I-70 CORRIDOR AND NORTHWARD, EARLY THURSDAY NIGHT. AFTER MIDNIGHT THURSDAY, THE PRECIP CHANCES WILL CHANGE TO 30 TO 40 PERCENT, AND ONLY IN TREGO, ELLIS AND RUSH COUNTIES. THE NAM MODEL IS HINTING AT QPF FROM 0.60 TO 0.80-INCH IN OUR NORTHWEST FROM HAYS TO SCOTT CITY, BUT HAVE A HARD TIME BUYING THAT MUCH PERCEPTIBLE WATER WILL FALL OUT, BASED ON RECENT TRENDS. TRIMMED THURSDAY NIGHT QPF TO AROUND 0.25 TO 0.30-INCH. AS THAT SHORT WAVE EXITS, ANOTHER SMALL SCALE WAVE IS EJECTED FROM THE LARGE UPPER LOW OFF THE COAST OF BAJA CALIFORNIA. THIS SECOND WAVE IS LESS ORGANIZED THAN THE FIRST, AND WILL BRING THUNDERSTORM CHANCES TO THAT AREA NORTH OF A LINE FROM JOHNSON CITY TO LA CROSSE. THE UPPER BAJA LOW CUTS OFF SATURDAY NIGHT PER THE ECMWF AND GFS MODELS, AND AN UPPER HIGH BEGINS TO BUILD OVER TEXAS. FOR NOW, PLAN TO KEEP SUNDAY AND SUNDAY NIGHT FREE OF PRECIPITATION CHANCES, BUT OUR EXTREME EAST WILL HAVE A SLIGHT CHANCE MONDAY AFTERNOON AS UPPER DIVERGENCE WILL BE OVERHEAD, AND A DOWN SLOPE FLOW WILL BE EVOLVING. A COLD FRONT WILL SINK INTO SOUTHWEST KANSAS MONDAY NIGHT, AND THERE COULD BE A FEW SCATTERED STORMS IN OUR SOUTHEAST ZONES WHERE THE GREATEST MOISTURE WILL BE, SUCH AS SOUTHEAST OF LINE FORM LARNED TO DODGE CITY TO ASHLAND MONDAY NIGHT. THE CR-EXTENDED BLEND PROCEDURE PLACED 30 POPS IN MY EXTREME THREE EASTERN COUNTIES OF STAFFORD, PRATT AND BARBER WEDNESDAY, OR DAY 7. KNOCKED THOSE POPS DOWN TO 20 PERCENT, AS THE TIMING AND PLACEMENT OF THE NEXT WAVE COULD BE JUST ABOUT ANYWHERE AROUND THAT TIME. TEMPERATURES WILL BE RELATIVELY HOT DURING THE EXTENDED. OVERNIGHT MINIMUM TEMPERATURES WILL GENERALLY BE IN THE MID 60S TO LOWER 70S (SE, PRATT AND BARBER COUNTIES), WITH PERHAPS MONDAY NIGHT/TUESDAY MORNING THE COOLEST MORNING WITH MIN TEMPS FROM THE LOWER 60S IN SCOTT CITY TO 70 DEGREES IN MEDICINE LODGE. MAXIMUM TEMPERATURES WILL START OUT FRIDAY IN THE LOWER 90S NORTH OF I-70 AND RANGE TO THE MID 90S ALONG THE OKLAHOMA BORDER. BY SUNDAY, MAXIMUM TEMPERATURES WILL BE IN THE LOWER TO MID 90S ACROSS ALL OF SOUTHWEST KANSAS, THEN WARM TO PERHAPS THE WARMEST DAY MONDAY. HIGHS MONDAY SHOULD TOP OUT IN THE MID TO UPPER 90S, WITH THE ELKHART AREA BEING NEAR THE CENTURY MARK. THE WEAK COLD FRONT WILL SLIP THROUGH MONDAY NIGHT (BEST GUESS), AND KNOCK HIGHS DOWN A NOTCH INTO THE LOWER TO MID 90S BOTH TUESDAY AND WEDNESDAY. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING) ISSUED AT 600 PM CDT WED JUN 13 2012 VFR CONDITIONS WILL PREVAIL THROUGH LATE TONIGHT. HOWEVER, INCREASINGLY HIGH RELATIVE HUMIDITY LEVELS COMBINED WITH SOMEWHAT LIGHTER WINDS LATE TONIGHT WILL ALLOW FOR THE POSSIBLE DEVELOPMENT OF LOW LEVEL STRATUS FROM WESTERN OKLAHOMA AND THE TEXAS PANHANDLE NORTHWARD INTO PORTIONS OF SOUTHWEST KANSAS. MVFR CIGS CANNOT BE RULED OUT IN THE VICINITY OF KGCK AND KDDC GENERALLY AFTER 07Z. ALTHOUGH LESS LIKELY, IFR CIGS MAY BE POSSIBLE BRIEFLY TOWARD DAYBREAK. AS FOR WINDS, A LEE SIDE TROUGH OF LOW PRESSURE WILL PERSIST ACROSS EXTREME EASTERN COLORADO TONIGHT HELPING KEEP WINDS SOUTHERLY 10 TO 20KT OVERNIGHT INTO EARLY THURSDAY MORNING. && .PRELIMINARY POINT TEMPS/POPS... DDC 67 96 70 93 / 20 20 20 20 GCK 68 97 70 93 / 20 20 30 20 EHA 67 96 69 91 / 20 20 20 20 LBL 68 96 71 93 / 20 10 20 20 HYS 68 97 68 90 / 20 30 50 20 P28 68 95 76 94 / 20 20 20 20 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...RUSSELL SHORT TERM...RUSSELL LONG TERM...BURKE AVIATION...JJOHNSON
AREA FORECAST DISCUSSION
NWS CARIBOU ME
703 PM EDT TUE JUN 12 2012 .SYNOPSIS... A COLD FRONT WILL APPROACH FROM THE WEST TONIGHT AND SLOWLY CROSS THE REGION ON WEDNESDAY THEN MOVE EAST WEDNESDAY NIGHT. HIGH PRESSURE FROM NORTHERN CANADA WILL SLOWLY BUILD TOWARD THE REGION THROUGH THE REMAINDER OF THE WEEK INTO THE WEEKEND. && .NEAR TERM /THROUGH WEDNESDAY/... 700 PM UPDATE: USING THE RUC MODEL AND RADAR TREND, HAVE DELAYED THE ONSET OF SHOWERS ACROSS MOST OF THE REGION FROM LATE TONIGHT UNTIL WEDNESDAY MORNING. ALSO INCREASED CLOUDS A BIT FASTER TONIGHT THAN PREVIOUS FORECAST BASED ON RH PROGS. PREVIOUS DISCUSSION: A COLD FRONT CURRENTLY STRETCHING FROM WESTERN QUEBEC SOUTHWARD THROUGH THE GREAT LAKES WILL CONTINUE TO TREK EASTWARD TONIGHT AND WILL PASS ACROSS THE STATE TOMORROW. THIS FEATURE IS PRODUCING A SWATH OF LIGHT TO MODERATE SHOWERS ACROSS EASTERN NEW YORK AND WESTERN NEW ENGLAND THIS AFTERNOON, AND THIS TOO WILL SHIFT EASTWARD. PRECIPITATION SHOULD REACH WESTERN SECTIONS LATE THIS EVENING, BY AROUND MIDNIGHT, BUT IT WILL BE EARLY TOMORROW MORNING BEFORE IT MAKES IT INTO EASTERN MAINE. NOT SEEING MUCH EVIDENCE OF SURFACE BASED OR ELEVATED INSTABILITY OVERNIGHT, SO THERE SHOULDN`T BE ANY THUNDER. HOWEVER HAVE INCLUDED THE CHANCE OF THUNDERSTORMS TOMORROW AFTERNOON WITH THE ACTUAL FRONTAL PASSAGE. HEAVY RAIN IS ALSO A POSSIBILITY AS PWATS WILL BE RUNNING HIGH, 1 TO 1.5+ INCHES, BUT GIVEN THAT THIS SYSTEM WILL BE WEAKENING AS IT MOVES THROUGH HAVE OPTED TO NOT INCLUDE HEAVY RAIN IN THE FORECAST FOR NOW. RAINFALL TOTALS WILL BE HIGHEST IN CENTRAL AND WESTERN MAINE, WHERE 0.50 TO 0.75 INCHES ARE EXPECTED THROUGH EARLY TOMORROW EVENING. AMOUNTS DROP OFF AS YOU MOVE SOUTH AND EAST, WITH A TENTH TO A THIRD OF AN INCH ACROSS EASTERN AND DOWNEAST MAINE. OVERNIGHT LOWS WILL BE MILD GIVEN THE INFLUX OF MOISTURE, WITH MOST LOCATIONS DROPPING INTO THE MID AND UPPER 50S. TOMORROW WILL BE MUCH COOLER THAN THE PREVIOUS COUPLE OF DAYS; HIGHS ARE EXPECTED TO BE IN THE MID AND UPPER 60S. && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/... MODELS APPEAR TO REASONABLY CONSISTENT WITH THE DEPARTURE TIME OF SHWRS E OF THE FA WED NGT WITH MAX THU 00-06Z QPF MSLY LESS THAN 0.10 INCHES FOR LOCATIONS EXPERIENCING RNFL...WITH ALL LOCATIONS DRYING BY THU MORN. WITH WINDS BECOMING N AT 5 TO 10 MPH BEHIND A COLD FRONT LATE WED NGT AND ERLY THU MORN...CURRENT THINKING IS THAT THERE WILL NOT BE MUCH TM FOR PATCHY FOG TO FORM IN THE WAKE OF RNFL...SO FOR NOW WE DID NOT INCLUDE ANY FOG IN THE GRIDS FOR THIS PD...BUT BRIEF FOG CANNOT BE COMPLETELY RULED FOR A FEW LOCATIONS. OTHERWISE...MODELS HAVE BACKED OFF OF KEEPING CLDNSS AND ASSOCIATED SHWRS WITH THE UPPER LOW SE OF NOVA SCOTIA ACROSS SRN PTNS OF THE FA THU INTO THU NGT...SO WE LOWERED POPS BLO SLGT CHC AND ALLOWED FOR AT LEAST PARTIAL CLRG. WITH HI PRES BOTH AT THE SFC ALD ALF SLOWLY SUBSIDING SWRD FROM NRN/CNTRL CAN...FAIR SKIES AND LGT WINDS WILL CONT INTO FRI. LOW AND HI TEMPS WED NGT THRU THU NGT SHOULD BE NEAR NORMAL FOR THIS TM OF SEASON...WITH A SLIGHT WARMING TREND BEGINNING ON FRI. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... A STRONG RIDGE OF HIGH PRESSURE IS EXPECTED TO REMAIN ACROSS THE NORTHEAST THIS WEEKEND THROUGH MUCH OF NEXT WEEK BRING EXCEPTIONALLY WARM WEATHER TO THE REGION. AFTER A CLEAR NIGHT FRIDAY NIGHT...SATURDAY IS EXPECTED TO BE SUNNY WITH HIGH PRESSURE BOTH AT THE SURFACE AND ALOFT CRESTING OVER THE AREA. THE HIGH WILL REMAIN IN PLACE ON SUNDAY BRINGING ANOTHER MOSTLY SUNNY AND VERY WARM DAY. CLOUDS MAY INCREASE LATE IN THE DAY AS A WEAK SHORTWAVE SLIDES ACROSS THE NORTH AND SOME SCATTERED LATE DAY SHOWERS OR THUNDERSHOWERS ARE POSSIBLE ACROSS THE NORTH. SURFACE HIGH PRESSURE WILL THEN SLIDE SOUTH OF THE AREA EARLY NEXT WEEK. SOUTHWESTERLY WINDS JUST NORTH OF THE HIGH WILL THEN CHANNEL VERY WARM AIR INTO THE NORTHEAST FROM THE MIDWEST. THE WEAK DISTURBANCE OVER THE FAR NORTH MAY BRING SOME SHOWERS OR THUNDERSHOWERS ACROSS THE NORTH MONDAY INTO TUESDAY. OTHERWISE...THE DAYS WILL BE PARTLY CLOUDY...WARM AND HUMID. THE WARMEST AIR MAY THEN REACH THE STATE DURING MID WEEK WHEN TEMPS ON WEDNESDAY AND AGAIN ON THURSDAY COULD SOAR WELL INTO THE 80S AND POSSIBLY REACH 90 OR HIGHER IN SOME AREAS UNDER MOSTLY SUNNY SKIES. && .AVIATION /00Z WEDNESDAY THROUGH SUNDAY/... NEAR TERM: VFR CEILINGS WILL LOWER TO MVFR CEILING AFTER MIDNIGHT, AND REMAIN MVFR IN RAIN SHOWERS WEDNESDAY. CEILINGS WILL REMAIN MVFR THROUGH THE REMAINDER OF THE DAY AND MAY OCCASIONALLY DIP BELOW 1000 FT IN HEAVIER SHOWERS. SCATTERED THUNDERSTORMS ARE POSSIBLE WEDNESDAY AFTERNOON. SHORT TERM: ALL SITES WILL INITIALLY BEGIN MVFR WITH LOW CLGS AND OCNL VSBYS BETWEEN 3 TO 6 SM IN SHWRS WED EVE AND THEN IMPROVE TO VFR BY THU MORN BEHIND A COLD FRONT. ALL SITES SHOULD THEN CONT VFR THRU SUN. && .MARINE... NEAR TERM: A COLD FRONT WILL APPROACH THE WATERS LATE TONIGHT AND MOVE ACROSS THE AREA LATE TOMORROW. WHILE WINDS AND WAVES WILL INCREASE IN RESPONSE, THEY ARE EXPECTED TO REMAIN BELOW SMALL CRAFT LEVELS. THEREFORE, NO HEADLINES ARE NEEDED. SHORT TO LONG TERM: BOTH WINDS AND SEAS WILL REMAIN BLO SCA CRITERIA THRU SUN...WITH WINDS INCREASING TO 10 TO 15 KT FROM THE N BEHIND A COLD FRONT THU INTO THU NGT...THEN GRADUALLY DIMINISHING FRI INTO THE WEEKEND. USED A BLEND OF NAM12...GFS40 AND GMOS FOR WINDS AND KEPT CLOSE TO WW3 WV GUIDANCE FOR WV HTS... LOWERED FOR BAYS IMMEDIATELY ADJACENT TO THE COAST. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...NONE. && $$ NEAR TERM...FOSTER/HASTINGS SHORT TERM...VJN LONG TERM...BLOOMER AVIATION...FOSTER/HASTINGS MARINE...FOSTER/HASTINGS/VJN
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
950 PM EDT WED JUN 13 2012 .SYNOPSIS... HIGH PRESSURE WILL BRING DRY AND COOL AIR OVER THE UPPER OHIO VALLEY OVERNIGHT THROUGH THE END OF THE WEEK. THE STRETCH OF NICE WEATHER WILL CONTINUE THROUGH THE WEEKEND. && .NEAR TERM /THROUGH THURSDAY/... A LATE EVENING UPDATE HAS BEEN ISSUED TO MAKE MINOR ADJUSTMENTS TO THE SKY COVER AND TO ADJUST TEMPS DOWN OVERNIGHT ACROSS THE EASTERN RIDGES. THE LATEST RAP MID-LEVEL ANALYSIS INDICATES A 500MB RIDGE AXIS CENTERED ACROSS THE UPPER OHIO VALLEY WITH A DEEP LAYER OF DRY AIR IN PLACE. AT THE SURFACE, HIGH PRESSURE IS CENTERED ACROSS MICHIGAN. ASIDE FROM SOME THIN CIRRUS MOVING INTO EASTERN OHIO, SKIES ARE CLEAR WITH LIGHT AND NORTHERLY WINDS ACROSS THE AREA. THE MID-LEVEL RIDGE AXIS WILL SLOWLY NUDGE EASTWARD OVERNIGHT WITH THE HIGH SHIFTING INTO EASTERN CANADA ON THURSDAY. THE DRY PROFILE ALOFT WILL REMAIN IN PLACE ASIDE FROM THE THIN CIRRUS CROSSING THE AREA OVERNIGHT. CIRRUS WILL PASS ON THURSDAY, WITH ANOTHER CLEAR DAY EXPECTED ACROSS THE AREA. DESPITE THIN CIRRUS CROSSING THE AREA OVERNIGHT, RADIATIONAL COOLING IS EXPECTED. OVERNIGHT LOWS ARE CLOSER TO THE WARMER MET GUIDANCE, RANGING FROM THE UPPER 40S TO LOWER 50S ACROSS THE LOWLANDS. DRIER AIR ACROSS THE EASTERN RIDGES WILL ALLOW FOR TEMPS ACROSS THE HIGHER ELEVATIONS OF GARRETT, PRESTON, AND TUCKER COUNTIES TO RADIATE INTO THE LOWER TO MID 40S. WITH 850 TEMPS WARMING TO 11-13C TOMORROW AND ABUNDANT SUNSHINE, HIGHS WILL WARM TO NEAR NORMAL SEASONAL VALUES. && .SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY/... STRONG SURFACE HIGH TONIGHT WILL STAY OVER THE GREAT LAKES AND BRING LIGHT NORTH WINDS TO THE REGION. RADIATIONAL COOLING WILL BRING TEMPERATURES DOWN TO THE 50S AND 40S. SURFACE HIGH AND STRENGTHENING EASTERN RIDGE WILL ALLOW FOR COMFORTABLE CONDITIONS AND PLENTY OF SUNSHINE THROUGH THE REST OF THE PERIOD. NEAR NORMAL TEMPS THURSDAY THROUGH SATURDAY WITH JUST A COUPLE OF DEGREES ABOVE THE NORMAL HIGH. && .LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/... SATURDAY NIGHT THROUGH WEDNESDAY...MODEL AGREEMENT IS RATHER STRONG WITH REGARD TO THE DEVELOPMENT AND AMPLIFICATION OF AN UPPER RIDGE OVER THE EASTERN THIRD OF THE U.S. THROUGH THE EXTENDED FORECAST PERIOD. RUN-TO-RUN MODEL VARIATION HAS BEEN VIRTUALLY NIL...AND OTHER THAN A POSSIBLE IMPULSE RUNNING OVER THE RIDGE AXIS...THE CHANCES FOR PRECIPITATION THROUGHOUT THE EXTENDED FORECAST ARE FAIRLY LOW. WITH SURFACE HIGH PRESSURE IN CONTROL AND AN UPPER RIDGE AXIS TRANSITING THE AREA...COMPRESSIONAL WARMING AND INCREASING MIXING BEYOND NEXT WEEKEND WILL ALLOW TEMPERATURES TO SURGE WELL ABOVE NORMAL. AS MODEL CONSENSUS 850 MB TEMPERATURES RUN FROM ROUGHLY 16C UP TOWARD 20C...THE POSSIBILITY OF ECLIPSING 90F IN SOME LOCATIONS INCREASES DAY-BY-DAY THROUGH THE MIDDLE OF NEXT WEEK. AT THIS TIME...THE RIDGE BREAKDOWN FOR OUR AREA STILL SEEMS TO BE FAR ENOUGH OUT INTO THE FUTURE TO BE BEYOND THE FORECAST PERIOD...HOWEVER THE ECMWF BECOMES SOMEWHAT FLATTER BY THE MIDDLE OF NEXT WEEK SUCH THAT A FEW SHOWERS OR THUNDERSTORMS IN AFTERNOON INSTABILITY CANNOT BE RULED OUT...PARTICULARLY NORTH OF PITTSBURGH. HOWEVER...ALL THINGS CONSIDERED...A DRY SUMMER-LIKE PATTERN LOOKS TO CONTINUE FOR THE EASTERN THIRD OF THE COUNTRY. FRIES && .AVIATION /02Z THURSDAY THROUGH MONDAY/... HIGH PRESSURE WILL BRING GENERALLY CLEAR SKIES AND VFR WEATHER FOR TONIGHT AND THURSDAY. GOOD RADIATIONAL COOLING WILL PRODUCE OVERNIGHT INVERSIONS AND RESULT IN LIGHT AND VARIABLE WINDS. WITH DAYTIME HEATING WINDS SHOULD TURN LIGHT EASTERLY THURSDAY. .OUTLOOK...WEDNESDAY NIGHT THROUGH SUNDAY... HIGH PRESSURE WILL ALLOW FOR VFR CONDITIONS TO PREVAIL ACROSS THE TERMINALS THROUGH SUNDAY. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...NONE. WV...NONE. && $$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
736 PM EDT WED JUN 13 2012 .SYNOPSIS... HIGH PRESSURE WILL BRING DRY AND COOL AIR OVER THE UPPER OHIO VALLEY OVERNIGHT THROUGH THE END OF THE WEEK. THE STRETCH OF NICE WEATHER WILL CONTINUE THROUGH THE WEEKEND. && .NEAR TERM /THROUGH THURSDAY/... AN EARLY EVENING ENHANCED SHORT TERM FORECAST UPDATE HAS BEEN ISSUED WITH LITTLE CHANGE OTHER THAN TO INCREASE SKY GRIDS SLIGHTLY OVERNIGHT AS CIRRUS PASSES OVER THE AREA. THE LATEST RAP MID-LEVEL ANALYSIS INDICATES A 500MB RIDGE AXIS CENTERED ACROSS THE UPPER OHIO VALLEY WITH A DEEP LAYER OF DRY AIR IN PLACE. AT THE SURFACE, HIGH PRESSURE IS CENTERED ACROSS MICHIGAN. IN THIS PATTERN, SKIES ARE CLEAR WITH LIGHT AND NORTHERLY WINDS ACROSS THE AREA. THE MID-LEVEL RIDGE AXIS WILL SLOWLY NUDGE EASTWARD OVERNIGHT WITH THE HIGH SHIFTING INTO EASTERN CANADA ON THURSDAY. THE DRY PROFILE ALOFT WILL REMAIN IN PLACE ASIDE FROM SOME THIN CIRRUS CROSSING THE AREA OVERNIGHT. CIRRUS WILL PASS ON THURSDAY, WITH ANOTHER CLEAR DAY EXPECTED ACROSS THE AREA. DESPITE THIN CIRRUS CROSSING THE AREA, A STRONG RADIATIONAL COOLING NIGHT IS EXPECTED. OVERNIGHT LOWS ARE CLOSER TO THE WARMER MET GUIDANCE, RANGING FROM THE UPPER 40S TO LOWER 50S. WITH 850 TEMPS WARMING TO 11-13C TOMORROW AND ABUNDANT SUNSHINE, HIGHS WILL WARM TO NEAR NORMAL SEASONAL VALUES. && .SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY/... STRONG SURFACE HIGH TONIGHT WILL STAY OVER THE GREAT LAKES AND BRING LIGHT NORTH WINDS TO THE REGION. RADIATIONAL COOLING WILL BRING TEMPERATURES DOWN TO THE 50S AND 40S. SURFACE HIGH AND STRENGTHENING EASTERN RIDGE WILL ALLOW FOR COMFORTABLE CONDITIONS AND PLENTY OF SUNSHINE THROUGH THE REST OF THE PERIOD. NEAR NORMAL TEMPS THURSDAY THROUGH SATURDAY WITH JUST A COUPLE OF DEGREES ABOVE THE NORMAL HIGH. && .LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/... SATURDAY NIGHT THROUGH WEDNESDAY...MODEL AGREEMENT IS RATHER STRONG WITH REGARD TO THE DEVELOPMENT AND AMPLIFICATION OF AN UPPER RIDGE OVER THE EASTERN THIRD OF THE U.S. THROUGH THE EXTENDED FORECAST PERIOD. RUN-TO-RUN MODEL VARIATION HAS BEEN VIRTUALLY NIL...AND OTHER THAN A POSSIBLE IMPULSE RUNNING OVER THE RIDGE AXIS...THE CHANCES FOR PRECIPITATION THROUGHOUT THE EXTENDED FORECAST ARE FAIRLY LOW. WITH SURFACE HIGH PRESSURE IN CONTROL AND AN UPPER RIDGE AXIS TRANSITING THE AREA...COMPRESSIONAL WARMING AND INCREASING MIXING BEYOND NEXT WEEKEND WILL ALLOW TEMPERATURES TO SURGE WELL ABOVE NORMAL. AS MODEL CONSENSUS 850 MB TEMPERATURES RUN FROM ROUGHLY 16C UP TOWARD 20C...THE POSSIBILITY OF ECLIPSING 90F IN SOME LOCATIONS INCREASES DAY-BY-DAY THROUGH THE MIDDLE OF NEXT WEEK. AT THIS TIME...THE RIDGE BREAKDOWN FOR OUR AREA STILL SEEMS TO BE FAR ENOUGH OUT INTO THE FUTURE TO BE BEYOND THE FORECAST PERIOD...HOWEVER THE ECMWF BECOMES SOMEWHAT FLATTER BY THE MIDDLE OF NEXT WEEK SUCH THAT A FEW SHOWERS OR THUNDERSTORMS IN AFTERNOON INSTABILITY CANNOT BE RULED OUT...PARTICULARLY NORTH OF PITTSBURGH. HOWEVER...ALL THINGS CONSIDERED...A DRY SUMMERLIKE PATTERN LOOKS TO CONTINUE FOR THE EASTERN THIRD OF THE COUNTRY. FRIES && .AVIATION /00Z THURSDAY THROUGH MONDAY/... HIGH PRESSURE WILL BRING GENERALLY CLEAR SKIES AND VFR WEATHER FOR TONIGHT AND THURSDAY. GOOD RADIATIONAL COOLING WILL PRODUCE OVERNIGHT INVERSIONS AND RESULT IN LIGHT AND VARIABLE WINDS. WITH DAYTIME HEATING WINDS SHOULD TURN LIGHT EASTERLY THURSDAY. .OUTLOOK...WEDNESDAY NIGHT THROUGH SUNDAY... HIGH PRESSURE WILL ALLOW FOR VFR CONDITIONS TO PREVAIL ACROSS THE TERMINALS THROUGH SUNDAY. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...NONE. WV...NONE. && $$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
325 PM EDT TUE JUN 12 2012 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 325 PM EDT TUE JUN 12 2012 12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW PROGRESSIVE UPR TROF EXTENDING FM HUDSON BAY INTO THE GRT LKS MOVING E IN ADVANCE OF UPR RDG OVER WRN CANADA. SHRTWV EMBEDDED WITHIN THIS TROF BROUGHT LOTS OF CLDS AND SOME -SHRA TO MAINLY THE NRN TIER INTO EARLY AFTN... BUT TREND THIS AFTN HAS BEEN FOR MORE SUNSHINE AS DNVA/ LARGER SCALE QVECTOR DVGC/MORE ACYC FLOW AND DRIER AIR SHOWN ON THE 12Z INL RAOB IS FOLLOWING IN THE WAKE OF THAT DISTURBANCE IN ADVANCE OF SFC HI PRES CENTERED OVER SE SDAKOTA. SKIES ARE MOCLR FM THE HI CENTER STRETCHING TOWARD LK WINNIPEG...WHERE THE 12Z RAOB AT THE PAS IN MANITOBA SHOWS A PWAT OF 0.28 INCH. SFC DEWPTS THIS AFTN HAVE MIXED OUT INTO THE LO-MID 30S IN THIS UPSTREAM AIRMASS. MORE CLDS ARE PRESENT A BIT FARTHER W IN THE NRN PLAINS IN THE RETURN SW FLOW ARND THE SFC HI AND IN ADVANCE OF SHRTWV TRACKING E ACRS WYOMING/MONTANA. 12Z BIS RAOB SHOWS MORE MSTR/PWAT OF 0.70 INCH NEAR THE WAD CLD BAND. MAIN FCST CONCERNS IN THE SHORT TERM REVOLVE ARND CLRG TRENDS THIS AFTN AND THEN TEMPS/POTENTIAL FOR FROST TNGT. TNGT...SFC HI PRES IS FCST TO MOVE E AND TO OVER NRN LWR MI BY 12Z WED. EXPECT ANY LINGERING CLDS TO DSPT LATE THIS AFTN/EARLY THIS EVNG WITH THE ARRIVAL OF MORE ACYC FLOW AND WARMER/DRIER AIR AT H925. STRONGER WSW FLOW ARND SFC HI IS FCST TO DVLP OVER THE NW HALF OF THE CWA AFT 06Z...WITH PWAT RISING AS THIS FLOW TAPS MORE MSTR SHOWN ON THE 12Z BIS RAOB. MOST SUSTAINED CONDITIONS FOR RADIATIONAL COOLING LOOK TO BE OVER THE SCNTRL AND E...WHERE THE GRADIENT FLOW WL REMAIN WEAKER/PWAT LOWER AND UNDER 0.5 INCH THRU 12Z WED. OPTED TO EXTEND GOING FROST ADVY NEAR THE WI BORDER TO INCLUDE MOST OF THE CWA FROM BARAGA TO THE E...WITH MIN TEMPS CLOSER TO THE LOWER END OF GUIDANCE IN THESE AREAS PER OBSVD MIXING OF DEWPTS UPSTREAM. WED...AS SFC HI PRES DRIFTS SLOWLY E ACRS LK HURON...STRONGER SW FLOW WL DVLP OVER THE ENTIRE CWA. WITH APRCH OF DISTURBANCE NOW MOVING THRU THE NRN PLAINS AND SOME MSTR RETURN...EXPECT AT LEAST SOME CLDS TO INVADE MAINLY THE WRN ZNS IN THE AFTN. ALTHOUGH THE GFS GENERATES SOME PCPN OVER THE FAR W LATE IN THE DAY...PREFER TO FOLLOW THE DRY 12Z NAM/CNDN/LOCAL WRF-ARW DUE TO VERY DRY NATURE OF LLVL AIRMASS. MIXING TO H8 ON NAM FCST SDNGS YIELDS HI TEMPS REBOUNDING TO 70 TO 75 AWAY FM LK MODERATION. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 325 PM EDT TUE JUN 12 2012 THE WEAK HIGH PRESSURE RIDGE IN PLACE FOR WEDNESDAY WILL SLIDE EASTWARD AS A TROUGH OVER THE CANADIAN PRAIRIE DIGS DOWN INTO THE NORTHERN PLAINS. MODELS AGREE THAT A SHORTWAVE WILL BE APPROACHING WESTERN UPPER MICHIGAN BY 00Z THURSDAY...THOUGH THERE SEEMS TO BE DIFFERENCES WITH HOW STRONG IT WILL BE. THE GEM/ECMWF SEEM TO AGREE ON A WEAKER SOLUTION...WHILE THE GFS DEVELOPS A SMALL TROUGH. THE GFS ALSO AMPLIFIES THE EXITING RIDGE MUCH MORE THAN THE OTHER MODELS. WILL STICK WITH A BLEND MORE SIMILAR TO THE GEM/ECMWF FOR NOW GIVEN THEIR AGREEMENT...THOUGH CONFIDENCE IS NOT VERY HIGH. THIS KEEPS MOST OF THE PRECIPITATION THAT WILL OCCUR WITH THIS SHORTWAVE OVER WESTERN LAKE SUPERIOR AND THE WEST HALF OF THE CWA. WILL KEEP LOW CHANCE POPS OVER THESE AREAS TO ACCOUNT FOR UNCERTAINTY DURING THE DAY ON THURSDAY. MODEL SOUNDINGS SUGGEST MIXING TO AROUND 850MB...WHICH PUTS HIGHS IN THE 70S AND PERHAPS LOW 80S. DESPITE INCOMING CLOUD COVER WITH THE SHORTWAVE...EXPECT THE WARMEST TEMPERATURES TO BE OUT WEST WITH THE HIGHEST 850MB TEMPS OF AROUND 13C. WITH SKIES MOSTLY SUNNY OUT EAST...EXPECT MIXING TO BRING RELATIVE HUMIDITY DOWN INTO THE 30 PERCENT RANGE. WITH THE STRONGER PRESSURE GRADIENT ASSOCIATED WITH THE LOW PRESSURE SYSTEM...EXPECT GUSTY SOUTHERLY TO SOUTHEASTERLY WINDS ACROSS MUCH OF THE AREA...MAINLY NORTH CENTRAL AND OVER LAKE SUPERIOR. HIGHEST GUSTS ARE EXPECTED TO BE AROUND 25 KNOTS. FRIDAY THE TROUGH WILL SWING JUST NORTH OF LAKE SUPERIOR...REACHING HUDSON BAY BY 00Z SATURDAY. MODELS SEEM TO BE IN FAIRLY GOOD AGREEMENT ON THE AMOUNT OF QPF ASSOCIATED WITH THE PASSING FRONT ACROSS WEST AND CENTRAL UPPER MICHIGAN...WITH AROUND 0.25-0.50 INCH IMPACTING THE AREA. THE NAM BRINGS THE FRONT ALL THE WAY THROUGH THE CWA...BRINGING 0.25 INCH TO THE EASTERN AREAS. THE ECMWF/GEM/GFS TAKE THE BEST UPPER LEVEL FORCING NORTHWARD /PER 850-500MB QVECTOR CONVERGENCE/ AND THEREFORE KEEP MUCH OF THE EASTERN CWA DRY. THERE ARE ALSO DIFFERENCES IN TIMING OF PRECIPITATION...SO HAVE LOWERED CONFIDENCE IN PUTTING SPECIFICS INTO THE FORECAST. KEPT THE BEST CHANCES OVER LAKE SUPERIOR AND ACROSS THE WEST AND CENTRAL. MU/ML CAPE VALUES THURSDAY NIGHT INTO FRIDAY AFTERNOON RANGE FROM AROUND 200-1000 J/KG...SO KEPT THUNDER CHANCES IN. WITH PRESSURE GRADIENT REMAINING TIGHT...WINDS WILL CONTINUE TO GUST INTO THE 20-25 KNOT RANGE THROUGH FRIDAY EVENING. FOR THE EXTENDED /THE WEEKEND INTO TUESDAY/... FOR THE MOST PART...IT SEEMS THROUGH THE WEEKEND A RIDGE WILL CENTER ITSELF OVER LOWER MICHIGAN...AND SHORTWAVES WILL RIDE AROUND THE IT BRINGING CHANCES OF PRECIPITATION. FOR THE FIRST PART OF THE WORK WEEK...A STRONGER LOW PRESSURE TROUGH WILL SWING INTO THE NORTHERN PLAINS AND BRING ADDITIONAL PRECIPITATION/THUNDERSTORMS TO MUCH OF THE CWA. HOWEVER...MODELS DIFFER ON TIMING AND PLACEMENT OF FEATURES. THE GFS/GEM BRING A STRONGER RIDGE UP FROM THE PLAINS...KEEPING MUCH OF THE PRECIPITATION ASSOCIATED WITH A SECOND TROUGH/SHORTWAVE CONFINED TO THE WESTERN CWA OR NOT IN THE UPPER PENINSULA AT ALL. THE GFS EVENTUALLY DEVELOPS THE TROUGH INTO A CLOSED LOW...AND THEN MOVES THE PRECIPITATION THROUGH ON MONDAY. THE ECMWF KEEPS THE RIDGE FURTHER SOUTH AND EAST...AND BRINGS A MUCH MORE POTENT SHORTWAVE INTO UPPER MICHIGAN SATURDAY MORNING INTO MONDAY. WITH SUCH A VARIANCE IN SOLUTIONS...DO NOT FEEL CONFIDENT BUMPING UP ANY POPS. WILL KEEP THE MENTION OF THUNDER AS MODELS SEEM TO BRING IN A DECENT AMOUNT OF INSTABILITY THROUGH THE WEEKEND. AS FOR HIGH TEMPERATURES...850MB TEMPS LOOK TO BE IN THE 16-18C RANGE...SO WILL KEEP FORECASTED HIGHS IN THE UPPER 70S TO THE MID 80S. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 124 PM EDT TUE JUN 12 2012 ALTHOUGH SOME LOWER CLDS/MVFR CIGS MAY LINGER EARLY AT SAW...THE ARRIVAL OF HI PRES/DRIER AIR WL BRING VFR CONDITIONS THE REST OF THIS FCST PERIOD. GUSTY NW WINDS THIS AFTN WL ALSO DIMINISH BY TNGT WITH THE WEAKER PRES GRADIENT/LOSS OF DAYTIME HEATING. EXPECT A STRONGER SW FLOW TO DVLP ON WED ONCE THE HI CENTER SHIFTS TO THE E OVER NRN LOWER MI. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 325 PM EDT TUE JUN 12 2012 EXPECT NW WINDS UP TO 25-30 KTS INTO THIS EVENING OVER THE E TO DIMINISH OVERNIGHT WITH THE ARRIVAL OF A HI PRES RIDGE. THESE LIGHT WINDS WILL PERSIST INTO WED NIGHT AS THE HI REMAINS DOMINANT. THEN A STRONGER S WIND UP TO 25 KTS WILL IMPACT MAINLY THE NCENTRAL AND E PART OF THE LAKE ON THU/FRI UNDER A TIGHTER PRES GRADIENT BETWEEN THE HI DEPARTING TO THE E AND A LO PRES TROF APPROACHING FROM THE W. THEN LIGHTER WINDS WILL PREVAIL AGAIN THIS COMING WEEKEND WITH A WEAKER PRES GRADIENT FORECAST TO DOMINATE THE UPPER LAKES. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... FROST ADVISORY FROM 1 AM EDT /MIDNIGHT CDT/ TO 7 AM EDT /6 AM CDT/ WEDNESDAY FOR MIZ002-004>007-009>014-084-085. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...KC LONG TERM...MCB AVIATION...KC MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
125 PM EDT TUE JUN 12 2012 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 602 AM EDT TUE JUN 12 2012 WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A FAIRLY DEEP TROF EXTENDING FROM HUDSON BAY TO THE UPPER GREAT LAKES. ONE VORT MAX IS MOVING ACROSS LAKE SUPERIOR/UPPER MI ATTM AND ANOTHER WEAKER VORT MAX IS DROPPING SE INTO NRN MN. AT THE SFC...COLD FRONT HAS CLEARED THE FCST AREA...AND STRONG CAA IS UNDERWAY. 850MB TEMPS WHICH WERE RUNNING 10-16C AT 00Z SHOULD BE DOWN TO 0 TO 2C AT 18Z TODAY. WITH 850MB THERMAL TROF ARRIVING BY MID DAY...EXPECT PLENTY OF CLOUD COVER THRU THE MORNING HRS. SECONDARY SHORTWAVE BRUSHING THE AREA MIGHT BRING A FEW -SHRA/SPRINKLES ACROSS THE N AS WELL. THERE HAVE BEEN OCNL REPORTS OF LIGHT PCPN IN NRN MN DURING THE NIGHT. CLOUDS SHOULD SLOWLY BEGIN TO BREAK UP FROM W TO E DURING THE AFTN. MODELS ARE FAIRLY AGGRESSIVE WITH THE DRYING/CLEARING TREND. MIGHT BE A BIT TOO QUICK GIVEN PROXIMITY OF THERMAL TROF DURING THE LATTER PORTION OF THE DAY. UNDER CLOUDS/CAA...TEMPS SHOULD RISE VERY LITTLE THIS MORNING. IN FACT...TEMPS OVER THE E MAY FALL A FEW DEGREES DURING THE MORNING...ESPECIALLY CLOSE TO LAKE SUPERIOR. DURING THE AFTN... TEMPS MAY NOT GET OUT OF THE UPPER 40S E OF MUNISING GIVEN CHILLY AIR MASS AND STRONG GRADIENT FLOW ACROSS THE LAKE. ELSEWHERE...TEMPS WILL BEGIN TO RISE DURING THE AFTN AS CLOUDS SLOWLY BEGIN TO BREAK UP FROM W TO E. WITH EXPECTATION OF SOME SUN...UPPER 50S/LWR 60S SHOULD GENERALLY BE THE RULE. MAY REACH THE MID 60S OVER THE SCNTRL. COLD AIR ARRIVING TODAY WILL SET THE STAGE FOR A CHILLY/POSSIBLY FROSTY NIGHT TONIGHT. WITH SFC HIGH PRES MOVING INTO THE VCNTY... WINDS WILL DROP TO CALM/NEAR CALM. DRY AIR MASS (PRECIPITABLE WATER 35 TO 50PCT OF NORMAL THRU AT LEAST THE FIRST HALF OF THE NIGHT) WILL ALLOW FOR STRONG RADIATIONAL COOLING UNDER CLEAR SKIES. RIGHT NOW...IT APPEARS GREATEST COVERAGE OF FROST WILL BE OVER THE INTERIOR W HALF TOWARD THE WI BORDER. HAVE THUS OPTED FOR A FROST ADVY FOR GOGEBIC/IRON/DICKINSON LATE TONIGHT. MAY NEED TO EXPAND ADVY EASTWARD IN LATER FCSTS SINCE LOWEST PRECIPITABLE WATER LINGERS LONGEST OVER THE E. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 602 AM EDT TUE JUN 12 2012 WED MORNING WILL START WITH A SFC HIGH OVER THE CWA AND ZONAL FLOW ALOFT. AS THE SFC HIGH CENTER MOVES TO LAKE HURON BY 00Z THU...SLY FLOW WILL BE INCREASING THROUGH THE DAY SUNDAY. 850MB TEMPS WILL INCREASE FROM A CWA AVG OF 4C 12Z WED TO 9C 00Z THU. WE SHOULD BE ABLE TO MIX TO AROUND 800MB WED AFTERNOON...RESULTING IN HIGH TEMPS IN THE MID 60S TO MID 70S AND MIN RH VALUES OF 20 TO 30 PERCENT INTERIOR W...AND 25 TO 35 PERCENT INTERIOR E. THANKFULLY...WINDS SHOULD BE LESS THAN 15MPH WITH GUSTS OF 20MPH OR LESS. A SHORTWAVE TROUGH WILL MOVE E OVER LAKE WINNIPEG BY 00Z FRI...WITH A SFC LOW BENEATH IT AND A SFC TROUGH STRETCHING INTO WRN MN. WHILE THE SFC HIGH WILL HAVE MOVED WELL INTO QUEBEC...A SFC RIDGE WILL REMAIN OVER THE LOWER GREAT LAKES...INCREASING THE PRESSURE GRADIENT /AND THUS THE SLY FLOW/ OVER THE CWA. BY 00Z THU...850MB TEMPS WILL INCREASE TO AROUND 15C...MAKING FOR HIGH TEMPS IN THE 70S TO LOW 80S OVER MOST OF UPPER MI. WITH THE INCREASED SLY FLOW...MID LEVEL MOISTURE WILL BE GREATER THAN ON WED...BUT MODELS SHOW A VERY DRY LAYER AROUND 875MB...SO RH VALUES MAY FALL TO AROUND 30 PERCENT INLAND ON THU. SOME MODELS DO TRY TO BRING IN SOME PRECIP OVER FAR WRN UPPER MI AND WRN LAKE SUPERIOR...BUT MAJORITY OF GUIDANCE KEEPS THE PRECIP JUST W OF THE CWA. WILL GO WITH THE DRIER IDEA GIVEN VERY DRY LOW LEVELS AND DRY TREND AS OF LATE. GENERALLY...SFC WINDS SHOULD BE AROUND 15MPH WITH GUSTS OF 20-25MPH THU AFTERNOON/EVENING. THE WINNIPEG SHORTWAVE MOVES TO HUDSON BAY BY 18Z FRI...BUT THE SFC TROUGH SHOULD STAY NW OF THE CWA THROUGH FRI. MODELS ARE IN FAIRLY GOOD GENERAL AGREEMENT SHOWING SOME PRECIP ACROSS THE CWA FRI AS STRONG SLY FLOW CONTINUES. WE SHOULD SEE BETTER MOISTURE...SO SOME PRECIP IS POSSIBLE...BUT WE WILL BE LACKING A GOOD FORCING MECHANISM SO WILL NOT GO HIGHER THAN LOW CHANCE POPS. 850MB TEMPS INCREASE A DEGREE OR TWO FROM THU...RESULTING IN HIGH TEMPS FROM THE MID 70S TO MID 80S...WARMEST INTERIOR W. MODEL AGREEMENT INCREASES CONSIDERABLY FOR SAT THROUGH MON WITH THE PASSAGE OF A SERIES OF SHORTWAVES...DECREASING FORECAST CONFIDENCE SIGNIFICANTLY. MODELS ARE IN GENERAL AGREEMENT IN SHOWING A DEEP UPPER TROUGH MOVING INTO THE NRN PLAINS STATES MON...BUT HOW DEEP AND HOW FAR E THE TROUGH IS REMAINS IN QUESTION...AND THESE ASPECTS OF THIS SYSTEM WILL PLAY A CRUCIAL ROLE FOR THE FORECAST FOR MON. USED A CONSENSUS OF MODELS FOR THIS TIME FRAME. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 124 PM EDT TUE JUN 12 2012 ALTHOUGH SOME LOWER CLDS/MVFR CIGS MAY LINGER EARLY AT SAW...THE ARRIVAL OF HI PRES/DRIER AIR WL BRING VFR CONDITIONS THE REST OF THIS FCST PERIOD. GUSTY NW WINDS THIS AFTN WL ALSO DIMINISH BY TNGT WITH THE WEAKER PRES GRADIENT/LOSS OF DAYTIME HEATING. EXPECT A STRONGER SW FLOW TO DVLP ON WED ONCE THE HI CENTER SHIFTS TO THE E OVER NRN LOWER MI. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 602 AM EDT TUE JUN 12 2012 STRONG PUSH OF COLDER AIR INTO THE UPPER LAKES WILL RESULT IN W TO NW WINDS OF 20-30KT TODAY. THERE MAY BE A FEW GALE FORCE GUSTS ON SOME OF THE HIGHEST OBSERVING PLATFORMS OVER THE E HALF OF THE LAKE THRU THE MORNING HRS. HIGH PRES OVER THE NRN PLAINS WILL THEN ARRIVE OVER THE WESTERN GREAT LAKES TONIGHT...RESULTING IN WINDS DIMINISHING TO UNDER 20KT FROM W TO E LATE THIS AFTN THRU TONIGHT. THE HIGH WILL SHIFT TO QUEBEC WED NIGHT...AND THEN FOR THE REMAINDER OF THE WEEK...THE BASIC PATTERN WILL FEATURE A HIGH PRES RIDGE OVER THE ERN CONUS WITH A LOW PRES TROF FROM THE WRN HIGH PLAINS TO HUDSON BAY. A WAVE OF LOW PRES LIFTING TOWARD HUDSON BAY THU/FRI MAY RESULT IN A PERIOD OF SOUTHERLY 15-25KT WINDS THU/THU NIGHT OVER CNTRL LAKE SUPERIOR. OTHERWISE...WINDS WILL BE UNDER 20KT WED THRU SAT. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... FROST ADVISORY FROM MIDNIGHT TONIGHT TO 6 AM CDT WEDNESDAY FOR MIZ009>011. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...TITUS AVIATION...KC MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
744 AM EDT TUE JUN 12 2012 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 602 AM EDT TUE JUN 12 2012 WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A FAIRLY DEEP TROF EXTENDING FROM HUDSON BAY TO THE UPPER GREAT LAKES. ONE VORT MAX IS MOVING ACROSS LAKE SUPERIOR/UPPER MI ATTM AND ANOTHER WEAKER VORT MAX IS DROPPING SE INTO NRN MN. AT THE SFC...COLD FRONT HAS CLEARED THE FCST AREA...AND STRONG CAA IS UNDERWAY. 850MB TEMPS WHICH WERE RUNNING 10-16C AT 00Z SHOULD BE DOWN TO 0 TO 2C AT 18Z TODAY. WITH 850MB THERMAL TROF ARRIVING BY MID DAY...EXPECT PLENTY OF CLOUD COVER THRU THE MORNING HRS. SECONDARY SHORTWAVE BRUSHING THE AREA MIGHT BRING A FEW -SHRA/SPRINKLES ACROSS THE N AS WELL. THERE HAVE BEEN OCNL REPORTS OF LIGHT PCPN IN NRN MN DURING THE NIGHT. CLOUDS SHOULD SLOWLY BEGIN TO BREAK UP FROM W TO E DURING THE AFTN. MODELS ARE FAIRLY AGGRESSIVE WITH THE DRYING/CLEARING TREND. MIGHT BE A BIT TOO QUICK GIVEN PROXIMITY OF THERMAL TROF DURING THE LATTER PORTION OF THE DAY. UNDER CLOUDS/CAA...TEMPS SHOULD RISE VERY LITTLE THIS MORNING. IN FACT...TEMPS OVER THE E MAY FALL A FEW DEGREES DURING THE MORNING...ESPECIALLY CLOSE TO LAKE SUPERIOR. DURING THE AFTN... TEMPS MAY NOT GET OUT OF THE UPPER 40S E OF MUNISING GIVEN CHILLY AIR MASS AND STRONG GRADIENT FLOW ACROSS THE LAKE. ELSEWHERE...TEMPS WILL BEGIN TO RISE DURING THE AFTN AS CLOUDS SLOWLY BEGIN TO BREAK UP FROM W TO E. WITH EXPECTATION OF SOME SUN...UPPER 50S/LWR 60S SHOULD GENERALLY BE THE RULE. MAY REACH THE MID 60S OVER THE SCNTRL. COLD AIR ARRIVING TODAY WILL SET THE STAGE FOR A CHILLY/POSSIBLY FROSTY NIGHT TONIGHT. WITH SFC HIGH PRES MOVING INTO THE VCNTY... WINDS WILL DROP TO CALM/NEAR CALM. DRY AIR MASS (PRECIPITABLE WATER 35 TO 50PCT OF NORMAL THRU AT LEAST THE FIRST HALF OF THE NIGHT) WILL ALLOW FOR STRONG RADIATIONAL COOLING UNDER CLEAR SKIES. RIGHT NOW...IT APPEARS GREATEST COVERAGE OF FROST WILL BE OVER THE INTERIOR W HALF TOWARD THE WI BORDER. HAVE THUS OPTED FOR A FROST ADVY FOR GOGEBIC/IRON/DICKINSON LATE TONIGHT. MAY NEED TO EXPAND ADVY EASTWARD IN LATER FCSTS SINCE LOWEST PRECIPITABLE WATER LINGERS LONGEST OVER THE E. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 602 AM EDT TUE JUN 12 2012 WED MORNING WILL START WITH A SFC HIGH OVER THE CWA AND ZONAL FLOW ALOFT. AS THE SFC HIGH CENTER MOVES TO LAKE HURON BY 00Z THU...SLY FLOW WILL BE INCREASING THROUGH THE DAY SUNDAY. 850MB TEMPS WILL INCREASE FROM A CWA AVG OF 4C 12Z WED TO 9C 00Z THU. WE SHOULD BE ABLE TO MIX TO AROUND 800MB WED AFTERNOON...RESULTING IN HIGH TEMPS IN THE MID 60S TO MID 70S AND MIN RH VALUES OF 20 TO 30 PERCENT INTERIOR W...AND 25 TO 35 PERCENT INTERIOR E. THANKFULLY...WINDS SHOULD BE LESS THAN 15MPH WITH GUSTS OF 20MPH OR LESS. A SHORTWAVE TROUGH WILL MOVE E OVER LAKE WINNIPEG BY 00Z FRI...WITH A SFC LOW BENEATH IT AND A SFC TROUGH STRETCHING INTO WRN MN. WHILE THE SFC HIGH WILL HAVE MOVED WELL INTO QUEBEC...A SFC RIDGE WILL REMAIN OVER THE LOWER GREAT LAKES...INCREASING THE PRESSURE GRADIENT /AND THUS THE SLY FLOW/ OVER THE CWA. BY 00Z THU...850MB TEMPS WILL INCREASE TO AROUND 15C...MAKING FOR HIGH TEMPS IN THE 70S TO LOW 80S OVER MOST OF UPPER MI. WITH THE INCREASED SLY FLOW...MID LEVEL MOISTURE WILL BE GREATER THAN ON WED...BUT MODELS SHOW A VERY DRY LAYER AROUND 875MB...SO RH VALUES MAY FALL TO AROUND 30 PERCENT INLAND ON THU. SOME MODELS DO TRY TO BRING IN SOME PRECIP OVER FAR WRN UPPER MI AND WRN LAKE SUPERIOR...BUT MAJORITY OF GUIDANCE KEEPS THE PRECIP JUST W OF THE CWA. WILL GO WITH THE DRIER IDEA GIVEN VERY DRY LOW LEVELS AND DRY TREND AS OF LATE. GENERALLY...SFC WINDS SHOULD BE AROUND 15MPH WITH GUSTS OF 20-25MPH THU AFTERNOON/EVENING. THE WINNIPEG SHORTWAVE MOVES TO HUDSON BAY BY 18Z FRI...BUT THE SFC TROUGH SHOULD STAY NW OF THE CWA THROUGH FRI. MODELS ARE IN FAIRLY GOOD GENERAL AGREEMENT SHOWING SOME PRECIP ACROSS THE CWA FRI AS STRONG SLY FLOW CONTINUES. WE SHOULD SEE BETTER MOISTURE...SO SOME PRECIP IS POSSIBLE...BUT WE WILL BE LACKING A GOOD FORCING MECHANISM SO WILL NOT GO HIGHER THAN LOW CHANCE POPS. 850MB TEMPS INCREASE A DEGREE OR TWO FROM THU...RESULTING IN HIGH TEMPS FROM THE MID 70S TO MID 80S...WARMEST INTERIOR W. MODEL AGREEMENT INCREASES CONSIDERABLY FOR SAT THROUGH MON WITH THE PASSAGE OF A SERIES OF SHORTWAVES...DECREASING FORECAST CONFIDENCE SIGNIFICANTLY. MODELS ARE IN GENERAL AGREEMENT IN SHOWING A DEEP UPPER TROUGH MOVING INTO THE NRN PLAINS STATES MON...BUT HOW DEEP AND HOW FAR E THE TROUGH IS REMAINS IN QUESTION...AND THESE ASPECTS OF THIS SYSTEM WILL PLAY A CRUCIAL ROLE FOR THE FORECAST FOR MON. USED A CONSENSUS OF MODELS FOR THIS TIME FRAME. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING) ISSUED AT 742 AM EDT TUE JUN 12 2012 THERMAL TROF APPROACHING THE AREA WILL BE CONDUCIVE FOR MAINTAINING BKN/OVC STRATOCU THRU THE MORNING HRS WITH CIGS PREDOMINATELY MVFR AT KIWD/KCMX/KSAW. PER UPSTREAM OBS...CIGS WILL PROBABLY BOUNCE TO VFR AT TIMES...ESPECIALLY HEADING INTO THE LATE MORNING/EARLY AFTN. DISTURBANCE PASSING THRU THE AREA MAY ALSO PRODUCE SOME -RA/SPRINKLES AT TIMES FOR THE NEXT 2-3HRS...PARTICULARLY AT KCMX. ARRIVAL OF DRIER AIR WILL WORK TO SCATTER OUT CLOUDS THIS AFTN/EARLY EVENING...BEGINNING FIRST AT KIWD AND LAST AT KSAW. INFLUX OF SHARPLY COLDER AIR WILL ALSO KEEP NW WINDS GUSTY TODAY...ESPECIALLY AT KCMX. WITH HIGH PRES NEARING AND LOSS OF DAYTIME HEATING/MIXING...WINDS WILL BECOME LIGHT THIS EVENING UNDER CLEAR SKIES. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 602 AM EDT TUE JUN 12 2012 STRONG PUSH OF COLDER AIR INTO THE UPPER LAKES WILL RESULT IN W TO NW WINDS OF 20-30KT TODAY. THERE MAY BE A FEW GALE FORCE GUSTS ON SOME OF THE HIGHEST OBSERVING PLATFORMS OVER THE E HALF OF THE LAKE THRU THE MORNING HRS. HIGH PRES OVER THE NRN PLAINS WILL THEN ARRIVE OVER THE WESTERN GREAT LAKES TONIGHT...RESULTING IN WINDS DIMINISHING TO UNDER 20KT FROM W TO E LATE THIS AFTN THRU TONIGHT. THE HIGH WILL SHIFT TO QUEBEC WED NIGHT...AND THEN FOR THE REMAINDER OF THE WEEK...THE BASIC PATTERN WILL FEATURE A HIGH PRES RIDGE OVER THE ERN CONUS WITH A LOW PRES TROF FROM THE WRN HIGH PLAINS TO HUDSON BAY. A WAVE OF LOW PRES LIFTING TOWARD HUDSON BAY THU/FRI MAY RESULT IN A PERIOD OF SOUTHERLY 15-25KT WINDS THU/THU NIGHT OVER CNTRL LAKE SUPERIOR. OTHERWISE...WINDS WILL BE UNDER 20KT WED THRU SAT. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... FROST ADVISORY FROM MIDNIGHT TONIGHT TO 6 AM CDT WEDNESDAY FOR MIZ009>011. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...TITUS AVIATION...ROLFSON MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
603 AM EDT TUE JUN 12 2012 .SHORT TERM...(TODAY) ISSUED AT 602 AM EDT TUE JUN 12 2012 WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A FAIRLY DEEP TROF EXTENDING FROM HUDSON BAY TO THE UPPER GREAT LAKES. ONE VORT MAX IS MOVING ACROSS LAKE SUPERIOR/UPPER MI ATTM AND ANOTHER WEAKER VORT MAX IS DROPPING SE INTO NRN MN. AT THE SFC...COLD FRONT HAS CLEARED THE FCST AREA...AND STRONG CAA IS UNDERWAY. 850MB TEMPS WHICH WERE RUNNING 10-16C AT 00Z SHOULD BE DOWN TO 0 TO 2C AT 18Z TODAY. WITH 850MB THERMAL TROF ARRIVING BY MID DAY...EXPECT PLENTY OF CLOUD COVER THRU THE MORNING HRS. SECONDARY SHORTWAVE BRUSHING THE AREA MIGHT BRING A FEW -SHRA/SPRINKLES ACROSS THE N AS WELL. THERE HAVE BEEN OCNL REPORTS OF LIGHT PCPN IN NRN MN DURING THE NIGHT. CLOUDS SHOULD SLOWLY BEGIN TO BREAK UP FROM W TO E DURING THE AFTN. MODELS ARE FAIRLY AGGRESSIVE WITH THE DRYING/CLEARING TREND. MIGHT BE A BIT TOO QUICK GIVEN PROXIMITY OF THERMAL TROF DURING THE LATTER PORTION OF THE DAY. UNDER CLOUDS/CAA...TEMPS SHOULD RISE VERY LITTLE THIS MORNING. IN FACT...TEMPS OVER THE E MAY FALL A FEW DEGREES DURING THE MORNING...ESPECIALLY CLOSE TO LAKE SUPERIOR. DURING THE AFTN... TEMPS MAY NOT GET OUT OF THE UPPER 40S E OF MUNISING GIVEN CHILLY AIR MASS AND STRONG GRADIENT FLOW ACROSS THE LAKE. ELSEWHERE...TEMPS WILL BEGIN TO RISE DURING THE AFTN AS CLOUDS SLOWLY BEGIN TO BREAK UP FROM W TO E. WITH EXPECTATION OF SOME SUN...UPPER 50S/LWR 60S SHOULD GENERALLY BE THE RULE. MAY REACH THE MID 60S OVER THE SCNTRL. COLD AIR ARRIVING TODAY WILL SET THE STAGE FOR A CHILLY/POSSIBLY FROSTY NIGHT TONIGHT. WITH SFC HIGH PRES MOVING INTO THE VCNTY... WINDS WILL DROP TO CALM/NEAR CALM. DRY AIR MASS (PRECIPITABLE WATER 35 TO 50PCT OF NORMAL THRU AT LEAST THE FIRST HALF OF THE NIGHT) WILL ALLOW FOR STRONG RADIATIONAL COOLING UNDER CLEAR SKIES. RIGHT NOW...IT APPEARS GREATEST COVERAGE OF FROST WILL BE OVER THE INTERIOR W HALF TOWARD THE WI BORDER. HAVE THUS OPTED FOR A FROST ADVY FOR GOGEBIC/IRON/DICKINSON LATE TONIGHT. MAY NEED TO EXPAND ADVY EASTWARD IN LATER FCSTS SINCE LOWEST PRECIPITABLE WATER LINGERS LONGEST OVER THE E. .LONG TERM...(TONIGHT THROUGH MONDAY) ISSUED AT 602 AM EDT TUE JUN 12 2012 WED MORNING WILL START WITH A SFC HIGH OVER THE CWA AND ZONAL FLOW ALOFT. AS THE SFC HIGH CENTER MOVES TO LAKE HURON BY 00Z THU...SLY FLOW WILL BE INCREASING THROUGH THE DAY SUNDAY. 850MB TEMPS WILL INCREASE FROM A CWA AVG OF 4C 12Z WED TO 9C 00Z THU. WE SHOULD BE ABLE TO MIX TO AROUND 800MB WED AFTERNOON...RESULTING IN HIGH TEMPS IN THE MID 60S TO MID 70S AND MIN RH VALUES OF 20 TO 30 PERCENT INTERIOR W...AND 25 TO 35 PERCENT INTERIOR E. THANKFULLY...WINDS SHOULD BE LESS THAN 15MPH WITH GUSTS OF 20MPH OR LESS. A SHORTWAVE TROUGH WILL MOVE E OVER LAKE WINNIPEG BY 00Z FRI...WITH A SFC LOW BENEATH IT AND A SFC TROUGH STRETCHING INTO WRN MN. WHILE THE SFC HIGH WILL HAVE MOVED WELL INTO QUEBEC...A SFC RIDGE WILL REMAIN OVER THE LOWER GREAT LAKES...INCREASING THE PRESSURE GRADIENT /AND THUS THE SLY FLOW/ OVER THE CWA. BY 00Z THU...850MB TEMPS WILL INCREASE TO AROUND 15C...MAKING FOR HIGH TEMPS IN THE 70S TO LOW 80S OVER MOST OF UPPER MI. WITH THE INCREASED SLY FLOW...MID LEVEL MOISTURE WILL BE GREATER THAN ON WED...BUT MODELS SHOW A VERY DRY LAYER AROUND 875MB...SO RH VALUES MAY FALL TO AROUND 30 PERCENT INLAND ON THU. SOME MODELS DO TRY TO BRING IN SOME PRECIP OVER FAR WRN UPPER MI AND WRN LAKE SUPERIOR...BUT MAJORITY OF GUIDANCE KEEPS THE PRECIP JUST W OF THE CWA. WILL GO WITH THE DRIER IDEA GIVEN VERY DRY LOW LEVELS AND DRY TREND AS OF LATE. GENERALLY...SFC WINDS SHOULD BE AROUND 15MPH WITH GUSTS OF 20-25MPH THU AFTERNOON/EVENING. THE WINNIPEG SHORTWAVE MOVES TO HUDSON BAY BY 18Z FRI...BUT THE SFC TROUGH SHOULD STAY NW OF THE CWA THROUGH FRI. MODELS ARE IN FAIRLY GOOD GENERAL AGREEMENT SHOWING SOME PRECIP ACROSS THE CWA FRI AS STRONG SLY FLOW CONTINUES. WE SHOULD SEE BETTER MOISTURE...SO SOME PRECIP IS POSSIBLE...BUT WE WILL BE LACKING A GOOD FORCING MECHANISM SO WILL NOT GO HIGHER THAN LOW CHANCE POPS. 850MB TEMPS INCREASE A DEGREE OR TWO FROM THU...RESULTING IN HIGH TEMPS FROM THE MID 70S TO MID 80S...WARMEST INTERIOR W. MODEL AGREEMENT INCREASES CONSIDERABLY FOR SAT THROUGH MON WITH THE PASSAGE OF A SERIES OF SHORTWAVES...DECREASING FORECAST CONFIDENCE SIGNIFICANTLY. MODELS ARE IN GENERAL AGREEMENT IN SHOWING A DEEP UPPER TROUGH MOVING INTO THE NRN PLAINS STATES MON...BUT HOW DEEP AND HOW FAR E THE TROUGH IS REMAINS IN QUESTION...AND THESE ASPECTS OF THIS SYSTEM WILL PLAY A CRUCIAL ROLE FOR THE FORECAST FOR MON. USED A CONSENSUS OF MODELS FOR THIS TIME FRAME. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 135 AM EDT TUE JUN 12 2012 GUSTY W TO NW WINDS WILL CONTINUE INTO TODAY AT KIWD/KSAW AND ESPECIALLY AT KCMX. UPSTREAM OBS SUGGEST MVFR CIGS SHOULD DEVELOP OVERNIGHT AT KIWD AND KCMX AND THEN IN THE MORNING AT KSAW AS COLDER AIR SETTLES INTO THE REGION. ANY MVFR CIGS SHOULD LIFT DURING THE AFTERNOON AS DRIER AIR MOVES IN. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 602 AM EDT TUE JUN 12 2012 STRONG PUSH OF COLDER AIR INTO THE UPPER LAKES WILL RESULT IN W TO NW WINDS OF 20-30KT TODAY. THERE MAY BE A FEW GALE FORCE GUSTS ON SOME OF THE HIGHEST OBSERVING PLATFORMS OVER THE E HALF OF THE LAKE THRU THE MORNING HRS. HIGH PRES OVER THE NRN PLAINS WILL THEN ARRIVE OVER THE WESTERN GREAT LAKES TONIGHT...RESULTING IN WINDS DIMINISHING TO UNDER 20KT FROM W TO E LATE THIS AFTN THRU TONIGHT. THE HIGH WILL SHIFT TO QUEBEC WED NIGHT...AND THEN FOR THE REMAINDER OF THE WEEK...THE BASIC PATTERN WILL FEATURE A HIGH PRES RIDGE OVER THE ERN CONUS WITH A LOW PRES TROF FROM THE WRN HIGH PLAINS TO HUDSON BAY. A WAVE OF LOW PRES LIFTING TOWARD HUDSON BAY THU/FRI MAY RESULT IN A PERIOD OF SOUTHERLY 15-25KT WINDS THU/THU NIGHT OVER CNTRL LAKE SUPERIOR. OTHERWISE...WINDS WILL BE UNDER 20KT WED THRU SAT. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... FROST ADVISORY FROM MIDNIGHT TONIGHT TO 6 AM CDT WEDNESDAY FOR MIZ009>011. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...TITUS AVIATION...JLB MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
137 AM EDT TUE JUN 12 2012 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 419 PM EDT MON JUN 11 2012 WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A FAIRLY DEEP TROF AND ASSOC STRONG SHORTWAVE MOVING FM ND INTO NW MN. THE EASTWARD MOVEMENT OF THIS SHORTWAVE IS HELPING TO SLOWLY PUSH A SFC COLD FRONT ACROSS WRN UPPER MI THIS AFTERNOON. LATEST 19Z SFC PLOT/ANALYSIS SHOWS THE FRONT IS ALONG A CRYSTAL FALLS-MICHIGAMME LINE. ALTHOUGH 12Z MODEL SNDGS INDICATE IN EXCESS OF 1000 J/KG MLCAPE WITH T/TD OF 82/63...VIS SATELLITE LOOP SHOWS LITTLE DVLPMT TO CU FIELD UPSTREAM OVER CENTRAL UPPER MI OR IMMEDIATELY UPSTREAM OVER NRN WI. SUSPECT THAT DRY ALOFT MOVING IN AHEAD OF THE SHORTWAVE AS NOTED ON VERY DRY 12Z KMPX SNDGS MAY BE INHIBITING CU DVLPMT OVER THE FCST AREA. TONIGHT...GIVEN LACK OF CU DVLPMT ON VIS SATELLITE MAY END UP EVENTUALLY HAVING TO BACK OFF ON POPS TO SLIGHT CHC OVER CENTRAL AND ERN COUNTIES FOR THIS EVENING AHEAD OF APPROACHING FRONT. IF SOME CONVECTION IS ABLE TO FIRE ALONG THE FRONT...THERE IS A CHANCE FOR AN ISOLATED STRONG TO SVR STORM GIVEN THE INSTABILITY AND DEEP LAYER SHEAR GREATER THAN 40 KTS OVER THE AREA. RELUCTANT TO PULL POPS OUT COMPLETELY SINCE FRONT IS STILL APPROACHING BUT CHC OF PCPN IS LOOKING MORE AND MORE DOUBTFUL THIS EVENING OVER CENTRAL AND ERN CWA. MODEL SNDGS INDICATE WEST WINDS ARE EXPECTED TO PICK UP BEHIND THE FRONT THIS EVENING ESPECIALLY OVER THE KEWEENAW PENINSULA WHERE PASSAGE OF SECONDARY COLD FRONT AND INCREASING MIXING/INSTABILITY WITH COLDER AIR COMING IN MAY PRODUCE GUSTS TO 40 MPH. LOOK FOR LOWS TO REACH INTO THE MID 40S WEST TO MID 50S SOUTH CENTRAL AND EAST. TUESDAY...THE 500MB TROUGH AXIS WILL MOVE ACROSS THE AREA MIDDAY ALONG WITH THE 8H THERMAL TROF AS 850 MB TEMPS LOWER TO AROUND 0C. WITH GOOD CAA IN THE WNW FLOW OVER THE AREA. WITH LIMITED MIXING ALONG THE LAKE SUPERIOR SHORE EXPECT HIGHS IN THE LOWER TO MID 50S WHILE DEEPER SOUTH CENTRAL WILL YIELD HIGHS IN THE LOWER TO MID 60S. INCREASINGLY ANTICYCLONIC SFC-850 MB FLOW AND RDGG BUILDING IN FROM THE WEST SHOULD SCOUR OUT LOW CLOUDS FROM WEST TO EAST IN THE AFTERNOON. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 419 PM EDT MON JUN 11 2012 THE SFC HIGH SHOULD BE DIRECTLY OVERHEAD FROM 00-06Z WEDNESDAY...BEFORE SHIFTING OFF TO QUEBEC WEDNESDAY AFTERNOON INTO THURSDAY. SIMILAR TO A FEW DAYS AGO...WE WILL MONITOR THE DEVELOPMENT OF AN ELONGATED SFC LOW STRETCHING FROM S CENTRAL CANADA THROUGH THE CO ROCKIES. FROST WILL REMAIN POSSIBLE TUESDAY NIGHT/WEDNESDAY MORNING...WITH TEMPS BOTTOMING OUT 31-36F INLAND FROM THE GREAT LAKES AS WINDS GO NEARLY CALM AND CLOUDS DISSIPATE. WEDNESDAY WILL LIKELY BE A BIT DRIER THAN ORIGINALLY THROUGH...WITH MIXED DEW POINTS IN THE MID 20S BY 18Z. THIS SCENARIO WOULD RESULT IN MIN RH VALUES NEAR 20 PERCENT OVER THE WEST HALF OF UPPER MI...AND 25-30 PERCENT EAST. EXPECT THE RETURN OF LIGHT/SOUTHERLY FLOW AS THE HIGH SHIFTS ACROSS LAKE HURON AND STRETCHES THROUGH QUEBEC...STILL BELOW 15MPH. DID PUSH THE FCST CLOSER TO THESE LOWEST VALUES. THE ELONGATED SFC LOW STRETCHING FROM SOUTHERN SASKATCHEWAN/MANITOBA THROUGH THE DAKOTAS AND E CO/NM THURSDAY MORNING WILL CONTINUE TO REMAIN NEARLY STEADY. ALTHOUGH THURSDAY SHOULD BE WARMER...WITH INCREASED SOUTHERLY WINDS /20-35KTS BETWEEN THE SFC AND 850MB/...MOISTURE SHOULD BE ON THE INCREASE AS WELL. MIN RH VALUES COULD STILL NEAR 30 PERCENT OVER PORTIONS OF INTERIOR W UPPER MI BY LATE MORNING/EARLY AFTERNOON. THE FCST FOR SUNDAY MONDAY REMAINS VERY UNCERTAIN...SO DID NOT GO TOO FAR IN DEPTH WITH ADJUSTMENTS FOR THAT PERIOD. THE WESTERN SFC LOW WILL BE LOCATED SOMEWHERE BETWEEN NWS ONTARIO AND MN BY 12Z MONDAY...WITH THE TRAILING COLD FRONT STILL REMAINING TO OUR W BY THE END OF THE DAY. THE RESULT SHOULD BE ANOTHER ROUND OF WARM/HOT WEATHER SATURDAY THROUGH MONDAY...AS S WINDS REMAIN STEADY AND 850MB TEMPS RISE AGAIN TO 16 TO 20C. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 135 AM EDT TUE JUN 12 2012 GUSTY W TO NW WINDS WILL CONTINUE INTO TODAY AT KIWD/KSAW AND ESPECIALLY AT KCMX. UPSTREAM OBS SUGGEST MVFR CIGS SHOULD DEVELOP OVERNIGHT AT KIWD AND KCMX AND THEN IN THE MORNING AT KSAW AS COLDER AIR SETTLES INTO THE REGION. ANY MVFR CIGS SHOULD LIFT DURING THE AFTERNOON AS DRIER AIR MOVES IN. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 419 PM EDT MON JUN 11 2012 LOW PRESSURE ACROSS HUDSON BAY WILL KEEP A TROUGH ACROSS LS THIS EVENING...AHEAD OF HIGH NEARING FROM THE WEST. EXPECT THE HIGH OVER MINNESOTA TUESDAY MORNING TO PUSH ACROSS THE UPPER GREAT LAKES TUESDAY AFTERNOON THROUGH WEDNESDAY...BEFORE EXITING ACROSS QUEBEC WEDNESDAY NIGHT. W-NW GUSTS OF 30 TO POSSIBLY 30KTS WILL SLIDE IN OVERNIGHT AND LINGER THROUGH THE DAY TUESDAY. A RIDGE WILL REMAIN ACROSS LS THROUGH SATURDAY...AS AN ELONGATED AREA OF LOW PRESSURE ORGANIZES ACROSS THE CENTRAL AND NORTHERN PLAINS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...VOSS LONG TERM...KF AVIATION...JLB MARINE...KF
AREA FORECAST DISCUSSION...CORRECTED
NWS WILMINGTON NC
1040 PM EDT WED JUN 13 2012 .SYNOPSIS... A COLD FRONT WILL APPROACH FROM THE NORTH AND MOVE ACROSS THE AREA THIS EVENING. SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE INTO THE EVENING. HIGH PRESSURE WILL BUILD IN LATE TONIGHT AND THURSDAY...BRINGING A RELATIVELY COOL AND DRY PATTERN WHICH WILL PERSIST INTO NEXT WEEK. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... AS OF 1040 PM WEDNESDAY...ISOLATED WEAK CONVECTION TO CONTINUE THROUGH MIDNIGHT ACROSS THE GRAND STRAND OF SC. LATEST RUC HRLY MODEL OUTPUT INDICATES YET ADDITIONAL WEAK SHEARED MID LEVEL VORT INTERACTING WITH A WEAK SFC BOUNDARY EVIDENT WITH THE LATEST HRRR SFC WIND FIELD. THE SFC BOUNDARY SHOULD PUSH SOUTH OF THE ILM CWA BY 2 AM THE LATEST...AND AS A RESULT HAVE KEPT A LOW CHANCE FOR POPS ACROSS THE GRAND STRAND TIL THIS BOUNDARIES DEPARTURE. DRIER AIR IE. LOWER DEWPOINTS...WILL BE A TAD SLOWER IN PROGRESSING ACROSS THE ILM CWA DURING THE OVERNIGHT. AS A RESULT HAVE TWEAKED OVERNIGHT MINS AND HRLY DEWPOINTS UPWARDS...ESPECIALLY ALONG THE IMMEDIATE COAST... TO ACCOMMODATE. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 3 PM WEDNESDAY...A COLD FRONT WILL BE OFF THE COAST AS THE FORECAST PERIOD BEGINS AND A LOW PRESSURE AREA WILL DEVELOP ALONG THE FRONT. THIS WILL INCREASE THE NORTHERLY WINDS OVER THE REGION AND COOLER AND DRIER AIR WILL SHIFT INTO THE AREA. HIGHS WILL BE IN THE LOWER 80S AND LOWS IN THE LOWER 60S. WITH THE DRIER AIR THE CHANCES OF PRECIPITATION ARE NIL. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... AS OF 3 PM WEDNESDAY...SURFACE HIGH PRESSURE NOSING IN FROM THE NORTHEAST WHILE OFFSHORE MID LEVEL TROUGH DEVELOPS OFF THE COAST FOR MUCH OF THE PERIOD. THIS LEADS TO A DEEP NORTHEASTERLY FLOW ACROSS THE COASTAL CAROLINAS FOR MOST OF THE PERIOD. TEMPERATURES WILL AVERAGE ROUGHLY A CATEGORY BELOW CLIMO BY DAY AND PERHAPS A FEW DEGREES MORE BY NIGHT...THERE COULD EVEN BE A FEW UPPER 50S WELL INLAND. THE SURFACE RIDGE BEGINS TO PROGRESS TO THE EAST BY TUESDAY TURNING THE FLOW FROM NE TO MORE EAST OR SOUTHEAST. THIS SHOULD LEAD TO SOME MOISTURE ADVECTION AND PERHAPS ISOLATED EARLY MORNING SHOWERS ALONG THE COAST. TEMPERATURES WILL ALSO TREND UPWARD SLIGHTLY. && .AVIATION /00Z WEDNESDAY THROUGH MONDAY/... AS OF 00Z...TERMINALS ARE CURRENTLY VFR. SANDWICHED BETWEEN DRIER MID-LEVEL AIR ADVECTING IN FROM THE NORTH FROM LBT TO THE WEST OF FLO...AND THE SEA BREEZE JUST INLAND OF THE COASTAL TERMINALS... SHOWERS AND THUNDERSTORMS ARE OCCURRING. THIS AREA OF ACTIVITY IS GRADUALLY DISSIPATING FROM NORTH TO SOUTH AS DRIER AIR FILTERS INTO NORTHERN PORTIONS OF THE AREA. EXCEPT FOR A SLIGHT CHANCE OF VCTS NEAR CRE/MYR 00-01Z...EXPECT NO THUNDERSTORM ACTIVITY AT THE TERMINALS THIS EVENING. CONVECTION SHOULD CONTINUE TO MOVE SOUTH AND GRADUALLY DIE OFF OVER THE NEXT SEVERAL HOURS WITH LOSS OF DAYTIME HEATING. AS HIGH PRESSURE BUILDS IN WITH DRYING LOW AND MID LEVELS VFR IS EXPECTED TO CONTINUE THROUGH THE OVERNIGHT HOURS. EAST TO SOUTHEAST WINDS AT THE COASTAL TERMINALS THIS EVENING WILL GRADUALLY BECOME NORTH- NORTHEAST BY MIDNIGHT. AFTER SUNRISE NORTH TO NORTHEAST WINDS CAN BE EXPECTED WITH OCCASIONAL GUSTS TO 20-25 KNOTS AT THE COASTAL TERMINALS. WRAP AROUND MOISTURE IN THE LOW LEVELS FROM A LOW PRESSURE AREA OFFSHORE MAY ADVECT IN FROM THE NORTHEAST AND MAY CONSTITUTE A LOW VFR CEILING DURING THE LATE MORNING AND AFTERNOON ESPECIALLY AT THE COASTAL TERMINALS. THE CHANCE OF ANY SHOWERS APPEAR TOO LOW TO MENTION IN TAFS ATTM. EXTENDED OUTLOOK...MAINLY VFR THROUGH THE FORECAST PERIOD WITH NORTHEASTERLY WINDS. A CHANCE OF SHOWERS SUNDAY AND MONDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 1040 PM WEDNESDAY...NE WINDS WILL BECOME DOMINATE DURING THE OVERNIGHT...INITIALLY 5 TO 10 KT...THEN FURTHER INCREASE TO 10 TO 15 KT DURING THE THU PRE-DAWN HRS. THIS A RESULT OF THE FRONT MOVING FURTHER SOUTH AND EAST FROM THE ILM COASTAL WATERS AS DECENT RIDGING FROM THE HIGH CENTERED OVER SE CANADA BECOMES MORE DOMINANT. SPEEDS COULD REACH AROUND 15 KT BY DAYBREAK FOR THE WATERS FROM CAPE FEAR NORTHWARD AS THE SFC PG TIGHTENS. OVERNIGHT SIGNIFICANT SEAS WILL RUN 2 TO 3 FT...EXCEPT UP TO 4 FT OFF CAPE FEAR. WIND DRIVEN WAVES WILL CONTINUE THE MORE DOMINANT PLAYER WITH REGARD TO SIG SEAS... WITH DOMINANT PERIODS AROUND 6 SECONDS. THE LAST OF THE CONVECTION COULD AFFECT THE NEAR SHORE WATERS SOUTH OF LITTLE RIVER INLET EARLY INTO THE PRE-DAWN HRS OF THU. .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 3 PM WEDNESDAY...A COLD FRONT WILL BE OFF THE COAST AS THE FORECAST PERIOD BEGINS AND A LOW PRESSURE AREA WILL DEVELOP ALONG THE FRONT. THIS WILL INCREASE THE NORTHERLY WINDS OVER THE REGION AND COOLER AND DRIER AIR WILL SHIFT INTO THE AREA. HIGHS WILL BE IN THE LOWER 80S AND LOWS IN THE LOWER 60S. WITH THE DRIER AIR THE CHANCES OF PRECIPITATION ARE NIL. LONG TERM /SATURDAY THROUGH SUNDAY/... AS OF 3 PM WEDNESDAY...RATHER UN-CLIMATOLOGICAL NE FLOW TO BE IN PLACE THROUGH THE PERIOD. HIGH PRESSURE NOSED INTO THE CAROLINAS FROM THE NORTHEAST FOR MUCH OF THE TIME. IN THIS COAST- PARALLEL FLOW THERE MAY BE A CONSIDERABLE GRADIENT IN WAVE HEIGHT FROM THE COAST TO THE 20NM FORECAST ZONE BORDER...AND FUTURE FORECASTS WILL HAVE TO DETERMINE WHETHER SOME 6 FT SEAS WILL BE CLOSE ENOUGH TO WARRANT A SMALL CRAFT ADVISORY ON SATURDAY. A SLIGHT EASE IN THE GRADIENT TRANSLATING TO AN APPROXIMATE 5KT DROP IN SUSTAINED WIND SPEED FOR SUNDAY SHOULD PRECLUDE ANY ADVISORIES BUT SCEC HEADLINES ARE TOUGH TO RULE OUT EARLY ON. AN EASTWARD JOG OF THE HIGH ON MONDAY WILL WEAKEN THE WINDS EVEN FURTHER RESULTING IN A MORE PRONOUNCED ABATING OF THE SEAS. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ SYNOPSIS...HAWKINS NEAR TERM...DCH SHORT TERM...HAWKINS LONG TERM...MBB AVIATION...MRR
AREA FORECAST DISCUSSION...CORRECTED
NWS WILMINGTON NC
750 PM EDT WED JUN 13 2012 .SYNOPSIS... A COLD FRONT WILL APPROACH FROM THE NORTH AND MOVE ACROSS THE AREA THIS EVENING. SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE INTO THE EVENING. HIGH PRESSURE WILL BUILD IN LATE TONIGHT AND THURSDAY...BRINGING A RELATIVELY COOL AND DRY PATTERN WHICH WILL PERSIST INTO NEXT WEEK. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... AS OF 715 PM WEDNESDAY...LATEST RUC HRLY MODEL OUTPUT INDICATES A WEAK MID LEVEL IMPULSE DRIVING SOUTH AIDING THE CONTINUED FIRING OF CONVECTION ACROSS THE ILM SC COUNTIES. IN ADDITION...THE SEA BREEZE AIDED BY OUTFLOW FROM ILM NC EARLIER CONVECTION...HAS PUSHED NEARLY 1 FULL COUNTY INLAND FROM THE ILM SC COAST. LOOK FOR THESE CLUSTERS OF CONVECTION TO CONTINUE TO PUSH SOUTH BY SOUTHWEST VIA LATEST STORM MOTIONS FROM HRLY PROGGED SOUNDINGS. WILL CONTINUE POPS FOR UP TO SEVERAL HRS AFTER SUNSET WITH CONVECTION EITHER DISSIPATING OR SLIDING SOUTH OF THE ILM CWA BY LATE THIS EVENING. THIS UPDATE WILL ALSO ADD A BIT MORE CLOUDINESS FOR SKY CONDITIONS FOR THE EVENING AND OVERNIGHT. CURRENT MIN TEMP GUIDANCE LOOKS AOK AND SEE NO TWEAKING NEEDED AT THIS TIME. PREVIOUS DISCUSSION............................................. AS OF 3 PM WEDNESDAY...A SURFACE TROUGH PUSHED OFFSHORE THIS MORNING AT ABOUT THE SAME TIME AS THE 500 MB TROUGH DID ALOFT. THIS ALLOWED A LIGHT BUT DEEP-LAYER NORTHERLY FLOW TO OVERSPREAD THE AREA. THE ACTUAL SURFACE COLD FRONT HAS LAGGED BOTH OF THESE FEATURES AND IS JUST NOW PRESSING INTO SOUTHEASTERN NORTH CAROLINA...ACCOMPANIED BY ENHANCED CUMULUS AND SCATTERED SHOWERS. WE EXPECT SHOWERS AND EVEN SOME THUNDERSTORMS TO INCREASE IN COVERAGE OVER THE NEXT COUPLE OF HOURS AS THE BOUNDARY PUSHES SOUTH INTO NORTHEASTERN SOUTH CAROLINA. BY 6 PM THE BEST CHANCES FOR RAIN SHOULD EXIST ALONG AND SOUTH OF A LINE FROM LAKE CITY TO BRITTONS NECK TO MYRTLE BEACH. THE NEW AIRMASS ADVECTING SOUTHWARD IS QUITE DISSIMILAR TO THE TROPICAL AIRMASS OF THE PAST SEVERAL DAYS: PRECIPITABLE WATER VALUES AROUND 1.6 INCHES CURRENTLY SHOULD FALL TO 1.0 INCH AFTER MIDNIGHT...AND TO 0.7 INCHES BY DAYBREAK THURSDAY. LOW PRESSURE WILL DEEPEN ALONG THE FRONT WELL OFFSHORE TONIGHT... WITH NORTH TO NORTHEASTERLY WINDS BRINGING A MILD AIRMASS SOUTH INTO THE CAROLINAS. 850 MB TEMPS DON`T BUDGE MUCH...BUT WEAK COOL ADVECTION IN THE SFC-900 MB LAYER WILL ALLOW LOWS TO FALL INTO THE LOWER TO MIDDLE 60S FOR MOST AREAS. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 3 PM WEDNESDAY...A COLD FRONT WILL BE OFF THE COAST AS THE FORECAST PERIOD BEGINS AND A LOW PRESSURE AREA WILL DEVELOP ALONG THE FRONT. THIS WILL INCREASE THE NORTHERLY WINDS OVER THE REGION AND COOLER AND DRIER AIR WILL SHIFT INTO THE AREA. HIGHS WILL BE IN THE LOWER 80S AND LOWS IN THE LOWER 60S. WITH THE DRIER AIR THE CHANCES OF PRECIPITATION ARE NIL. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... AS OF 3 PM WEDNESDAY...SURFACE HIGH PRESSURE NOSING IN FROM THE NORTHEAST WHILE OFFSHORE MID LEVEL TROUGH DEVELOPS OFF THE COAST FOR MUCH OF THE PERIOD. THIS LEADS TO A DEEP NORTHEASTERLY FLOW ACROSS THE COASTAL CAROLINAS FOR MOST OF THE PERIOD. TEMPERATURES WILL AVERAGE ROUGHLY A CATEGORY BELOW CLIMO BY DAY AND PERHAPS A FEW DEGREES MORE BY NIGHT...THERE COULD EVEN BE A FEW UPPER 50S WELL INLAND. THE SURFACE RIDGE BEGINS TO PROGRESS TO THE EAST BY TUESDAY TURNING THE FLOW FROM NE TO MORE EAST OR SOUTHEAST. THIS SHOULD LEAD TO SOME MOISTURE ADVECTION AND PERHAPS ISOLATED EARLY MORNING SHOWERS ALONG THE COAST. TEMPERATURES WILL ALSO TREND UPWARD SLIGHTLY. && .AVIATION /00Z WEDNESDAY THROUGH MONDAY/... AS OF 00Z...TERMINALS ARE CURRENTLY VFR. SANDWICHED BETWEEN DRIER MID-LEVEL AIR ADVECTING IN FROM THE NORTH FROM LBT TO THE WEST OF FLO...AND THE SEA BREEZE JUST INLAND OF THE COASTAL TERMINALS... SHOWERS AND THUNDERSTORMS ARE OCCURRING. THIS AREA OF ACTIVITY IS GRADUALLY DISSIPATING FROM NORTH TO SOUTH AS DRIER AIR FILTERS INTO NORTHERN PORTIONS OF THE AREA. EXCEPT FOR A SLIGHT CHANCE OF VCTS NEAR CRE/MYR 00-01Z...EXPECT NO THUNDERSTORM ACTIVITY AT THE TERMINALS THIS EVENING. CONVECTION SHOULD CONTINUE TO MOVE SOUTH AND GRADUALLY DIE OFF OVER THE NEXT SEVERAL HOURS WITH LOSS OF DAYTIME HEATING. AS HIGH PRESSURE BUILDS IN WITH DRYING LOW AND MID LEVELS VFR IS EXPECTED TO CONTINUE THROUGH THE OVERNIGHT HOURS. EAST TO SOUTHEAST WINDS AT THE COASTAL TERMINALS THIS EVENING WILL GRADUALLY BECOME NORTH- NORTHEAST BY MIDNIGHT. AFTER SUNRISE NORTH TO NORTHEAST WINDS CAN BE EXPECTED WITH OCCASIONAL GUSTS TO 20-25 KNOTS AT THE COASTAL TERMINALS. WRAP AROUND MOISTURE IN THE LOW LEVELS FROM A LOW PRESSURE AREA OFFSHORE MAY ADVECT IN FROM THE NORTHEAST AND MAY CONSTITUTE A LOW VFR CEILING DURING THE LATE MORNING AND AFTERNOON ESPECIALLY AT THE COASTAL TERMINALS. THE CHANCE OF ANY SHOWERS APPEAR TOO LOW TO MENTION IN TAFS ATTM. EXTENDED OUTLOOK...MAINLY VFR THROUGH THE FORECAST PERIOD WITH NORTHEASTERLY WINDS. A CHANCE OF SHOWERS SUNDAY AND MONDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 715 PM WEDNESDAY...NNE-ENE WINDS WILL BECOME DOMINATE THIS EVENING AT 5 TO 10 KT...THEN FURTHER INCREASE TO 10 TO 15 KT OVERNIGHT. THIS A RESULT OF THE FRONT MOVING FURTHER SOUTH AND EAST FROM THE ILM COASTAL WATERS AS DECENT RIDGING FROM THE HIGH CENTERED OVER SE CANADA BECOMES MORE DOMINANT. SPEEDS COULD REACH AROUND 15 KT BY DAYBREAK FOR THE WATERS FROM CAPE FEAR NORTHWARD. OVERNIGHT SIGNIFICANT SEAS WILL RUN 2 TO 3 FT...EXCEPT UP TO 4 FT OFF CAPE FEAR. WIND DRIVEN WAVES WILL CONTINUE THE MORE DOMINANT PLAYER FOR SIG SEAS WITH DOMINANT PERIODS AROUND 6 SECONDS. THE BEST POTENTIAL FOR CONVECTION WILL BE THIS EVENING FOR THE NEAR SHORE WATERS SOUTH OF LITTLE RIVER INLET. .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 3 PM WEDNESDAY...A COLD FRONT WILL BE OFF THE COAST AS THE FORECAST PERIOD BEGINS AND A LOW PRESSURE AREA WILL DEVELOP ALONG THE FRONT. THIS WILL INCREASE THE NORTHERLY WINDS OVER THE REGION AND COOLER AND DRIER AIR WILL SHIFT INTO THE AREA. HIGHS WILL BE IN THE LOWER 80S AND LOWS IN THE LOWER 60S. WITH THE DRIER AIR THE CHANCES OF PRECIPITATION ARE NIL. LONG TERM /SATURDAY THROUGH SUNDAY/... AS OF 3 PM WEDNESDAY...RATHER UN-CLIMATOLOGICAL NE FLOW TO BE IN PLACE THROUGH THE PERIOD. HIGH PRESSURE NOSED INTO THE CAROLINAS FROM THE NORTHEAST FOR MUCH OF THE TIME. IN THIS COAST- PARALLEL FLOW THERE MAY BE A CONSIDERABLE GRADIENT IN WAVE HEIGHT FROM THE COAST TO THE 20NM FORECAST ZONE BORDER...AND FUTURE FORECASTS WILL HAVE TO DETERMINE WHETHER SOME 6 FT SEAS WILL BE CLOSE ENOUGH TO WARRANT A SMALL CRAFT ADVISORY ON SATURDAY. A SLIGHT EASE IN THE GRADIENT TRANSLATING TO AN APPROXIMATE 5KT DROP IN SUSTAINED WIND SPEED FOR SUNDAY SHOULD PRECLUDE ANY ADVISORIES BUT SCEC HEADLINES ARE TOUGH TO RULE OUT EARLY ON. AN EASTWARD JOG OF THE HIGH ON MONDAY WILL WEAKEN THE WINDS EVEN FURTHER RESULTING IN A MORE PRONOUNCED ABATING OF THE SEAS. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ SYNOPSIS...HAWKINS NEAR TERM...DCH/TRA SHORT TERM...HAWKINS LONG TERM...MBB AVIATION...MRR
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
745 PM EDT WED JUN 13 2012 .SYNOPSIS... A COLD FRONT WILL APPROACH FROM THE NORTH AND MOVE ACROSS THE AREA THIS EVENING. SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE INTO THE EVENING. HIGH PRESSURE WILL BUILD IN LATE TONIGHT AND THURSDAY...BRINGING A RELATIVELY COOL AND DRY PATTERN WHICH WILL PERSIST INTO NEXT WEEK. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... AS OF 715 PM WEDNESDAY...LATEST RUC HRLY MODEL OUTPUT INDICATES A WEAK MID LEVEL IMPULSE DRIVING SOUTH AIDING THE CONTINUED FIRING OF CONVECTION ACROSS THE ILM SC COUNTIES. IN ADDITION...THE SEA BREEZE AIDED BY OUTFLOW FROM ILM NC EARLIER CONVECTION...HAS PUSHED NEARLY 1 FULL COUNTY INLAND FROM THE ILM SC COAST. LOOK FOR THESE CLUSTERS OF CONVECTION TO CONTINUE TO PUSH SOUTH BY SOUTHWEST VIA LATEST STORM MOTIONS FROM HRLY PROGGED SOUNDINGS. WILL CONTINUE POPS FOR UP TO SEVERAL HRS AFTER SUNSET WITH CONVECTION EITHER DISSIPATING OR SLIDING SOUTH OF THE ILM CWA BY LATE THIS EVENING. THIS UPDATE WILL ALSO ADD A BIT MORE CLOUDINESS FOR SKY CONDITIONS FOR THE EVENING AND OVERNIGHT. CURRENT MIN TEMP GUIDANCE LOOKS AOK AND SEE NO TWEAKING NEEDED AT THIS TIME. PREVIOUS DISCUSSION............................................. AS OF 3 PM WEDNESDAY...A SURFACE TROUGH PUSHED OFFSHORE THIS MORNING AT ABOUT THE SAME TIME AS THE 500 MB TROUGH DID ALOFT. THIS ALLOWED A LIGHT BUT DEEP-LAYER NORTHERLY FLOW TO OVERSPREAD THE AREA. THE ACTUAL SURFACE COLD FRONT HAS LAGGED BOTH OF THESE FEATURES AND IS JUST NOW PRESSING INTO SOUTHEASTERN NORTH CAROLINA...ACCOMPANIED BY ENHANCED CUMULUS AND SCATTERED SHOWERS. WE EXPECT SHOWERS AND EVEN SOME THUNDERSTORMS TO INCREASE IN COVERAGE OVER THE NEXT COUPLE OF HOURS AS THE BOUNDARY PUSHES SOUTH INTO NORTHEASTERN SOUTH CAROLINA. BY 6 PM THE BEST CHANCES FOR RAIN SHOULD EXIST ALONG AND SOUTH OF A LINE FROM LAKE CITY TO BRITTONS NECK TO MYRTLE BEACH. THE NEW AIRMASS ADVECTING SOUTHWARD IS QUITE DISSIMILAR TO THE TROPICAL AIRMASS OF THE PAST SEVERAL DAYS: PRECIPITABLE WATER VALUES AROUND 1.6 INCHES CURRENTLY SHOULD FALL TO 1.0 INCH AFTER MIDNIGHT...AND TO 0.7 INCHES BY DAYBREAK THURSDAY. LOW PRESSURE WILL DEEPEN ALONG THE FRONT WELL OFFSHORE TONIGHT... WITH NORTH TO NORTHEASTERLY WINDS BRINGING A MILD AIRMASS SOUTH INTO THE CAROLINAS. 850 MB TEMPS DON`T BUDGE MUCH...BUT WEAK COOL ADVECTION IN THE SFC-900 MB LAYER WILL ALLOW LOWS TO FALL INTO THE LOWER TO MIDDLE 60S FOR MOST AREAS. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 3 PM WEDNESDAY...A COLD FRONT WILL BE OFF THE COAST AS THE FORECAST PERIOD BEGINS AND A LOW PRESSURE AREA WILL DEVELOP ALONG THE FRONT. THIS WILL INCREASE THE NORTHERLY WINDS OVER THE REGION AND COOLER AND DRIER AIR WILL SHIFT INTO THE AREA. HIGHS WILL BE IN THE LOWER 80S AND LOWS IN THE LOWER 60S. WITH THE DRIER AIR THE CHANCES OF PRECIPITATION ARE NIL. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... AS OF 3 PM WEDNESDAY...SURFACE HIGH PRESSURE NOSING IN FROM THE NORTHEAST WHILE OFFSHORE MID LEVEL TROUGH DEVELOPS OFF THE COAST FOR MUCH OF THE PERIOD. THIS LEADS TO A DEEP NORTHEASTERLY FLOW ACROSS THE COASTAL CAROLINAS FOR MOST OF THE PERIOD. TEMPERATURES WILL AVERAGE ROUGHLY A CATEGORY BELOW CLIMO BY DAY AND PERHAPS A FEW DEGREES MORE BY NIGHT...THERE COULD EVEN BE A FEW UPPER 50S WELL INLAND. THE SURFACE RIDGE BEGINS TO PROGRESS TO THE EAST BY TUESDAY TURNING THE FLOW FROM NE TO MORE EAST OR SOUTHEAST. THIS SHOULD LEAD TO SOME MOISTURE ADVECTION AND PERHAPS ISOLATED EARLY MORNING SHOWERS ALONG THE COAST. TEMPERATURES WILL ALSO TREND UPWARD SLIGHTLY. && .AVIATION /00Z WEDNESDAY THROUGH MONDAY/... AS OF 00Z...TERMINALS ARE CURRENTLY VFR. SANDWICHED BETWEEN DRIER MID-LEVEL AIR ADVECTING IN FROM THE NORTH FROM LBT TO THE WEST OF FLO...AND THE SEA BREEZE JUST INLAND OF THE COASTAL TERMINALS... SHOWERS AND THUNDERSTORMS ARE OCCURRING. THIS AREA OF ACTIVITY IS GRADUALLY DISSIPATING FROM NORTH TO SOUTH AS DRIER AIR FILTERS INTO NORTHERN PORTIONS OF THE AREA. EXCEPT FOR A SLIGHT CHANCE OF VCTS FROM ACTIVITY TO THE WEST OF MYR 00-01Z...EXPECT NO THUNDERSTORM ACTIVITY AT THE TERMINALS THIS EVENING. CONVECTION SHOULD MOVE SOUTH AND GRADUALLY DIE OFF OVER THE NEXT SEVERAL HOURS WITH LOSS OF DAY-TIME HEATING. AS HIGH PRESSURE BUILDS IN WITH DRYING LOW AND MID-LEVELS...VFR IS EXPECTED TO CONTINUE THROUGH THE OVERNIGHT HOURS. EAST TO SOUTHEAST WINDS AT THE COASTAL TERMINALS THIS EVENING WILL GRADUALLY BECOME NORTH-NORTHEAST BY MIDNIGHT. AFTER SUNRISE NORTH TO NORTHEAST WINDS CAN BE EXPECTED WITH OCCASIONAL GUSTS TO-25 20 KNOTS AT THE COASTAL TERMINALS. ENOUGH WRAP AROUND MOISTURE IN THE LOW-MID LEVELS FROM A LOW PRESSURE AREA OFFSHORE MAY ADVECT IN FROM THE NORTHEAST TO CONSTITUTE A LOW VFR CEILING AT TIMES DURING THE LATE MORNING AND AFTERNOON...ESPECIALLY AT THE COASTAL TERMINALS. THE CHANCE OF ANY SHOWERS APPEAR TOO LOW TO MENTION IN TAFS ATTM. EXTENDED OUTLOOK...MAINLY VFR THROUGH THE FORECAST PERIOD WITH NORTHEASTERLY WINDS. A CHANCE OF SHOWERS SUNDAY AND MONDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 715 PM WEDNESDAY...NNE-ENE WINDS WILL BECOME DOMINATE THIS EVENING AT 5 TO 10 KT...THEN FURTHER INCREASE TO 10 TO 15 KT OVERNIGHT. THIS A RESULT OF THE FRONT MOVING FURTHER SOUTH AND EAST FROM THE ILM COASTAL WATERS AS DECENT RIDGING FROM THE HIGH CENTERED OVER SE CANADA BECOMES MORE DOMINANT. SPEEDS COULD REACH AROUND 15 KT BY DAYBREAK FOR THE WATERS FROM CAPE FEAR NORTHWARD. OVERNIGHT SIGNIFICANT SEAS WILL RUN 2 TO 3 FT...EXCEPT UP TO 4 FT OFF CAPE FEAR. WIND DRIVEN WAVES WILL CONTINUE THE MORE DOMINANT PLAYER FOR SIG SEAS WITH DOMINANT PERIODS AROUND 6 SECONDS. THE BEST POTENTIAL FOR CONVECTION WILL BE THIS EVENING FOR THE NEAR SHORE WATERS SOUTH OF LITTLE RIVER INLET. .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 3 PM WEDNESDAY...A COLD FRONT WILL BE OFF THE COAST AS THE FORECAST PERIOD BEGINS AND A LOW PRESSURE AREA WILL DEVELOP ALONG THE FRONT. THIS WILL INCREASE THE NORTHERLY WINDS OVER THE REGION AND COOLER AND DRIER AIR WILL SHIFT INTO THE AREA. HIGHS WILL BE IN THE LOWER 80S AND LOWS IN THE LOWER 60S. WITH THE DRIER AIR THE CHANCES OF PRECIPITATION ARE NIL. LONG TERM /SATURDAY THROUGH SUNDAY/... AS OF 3 PM WEDNESDAY...RATHER UNCLIMATOLOGICAL NE FLOW TO BE IN PLACE THROUGH THE PERIOD. HIGH PRESSURE NOSED INTO THE CAROLINAS FROM THE NORTHEAST FOR MUCH OF THE TIME. IN THIS COAST- PARALLEL FLOW THERE MAY BE A CONSIDERABLE GRADIENT IN WAVE HEIGHT FROM THE COAST TO THE 20NM FORECAST ZONE BORDER...AND FUTURE FORECASTS WILL HAVE TO DETERMINE WHETHER SOME 6 FT SEAS WILL BE CLOSE ENOUGH TO WARRANT A SMALL CRAFT ADVISORY ON SATURDAY. A SLIGHT EASE IN THE GRADIENT TRANSLATING TO AN APPROXIMATE 5KT DROP IN SUSTAINED WIND SPEED FOR SUNDAY SHOULD PRECLUDE ANY ADVISORIES BUT SCEC HEADLINES ARE TOUGH TO RULE OUT EARLY ON. AN EASTWARD JOG OF THE HIGH ON MONDAY WILL WEAKEN THE WINDS EVEN FURTHER RESULTING IN A MORE PRONOUNCED ABATING OF THE SEAS. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ SYNOPSIS...HAWKINS NEAR TERM...DCH/TRA SHORT TERM...HAWKINS LONG TERM...MBB AVIATION...MRR
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
715 PM EDT WED JUN 13 2012 .SYNOPSIS... A COLD FRONT WILL APPROACH FROM THE NORTH AND MOVE ACROSS THE AREA THIS EVENING. SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE INTO THE EVENING. HIGH PRESSURE WILL BUILD IN LATE TONIGHT AND THURSDAY...BRINGING A RELATIVELY COOL AND DRY PATTERN WHICH WILL PERSIST INTO NEXT WEEK. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... AS OF 715 PM WEDNESDAY...LATEST RUC HRLY MODEL OUTPUT INDICATES A WEAK MID LEVEL IMPULSE DRIVING SOUTH AIDING THE CONTINUED FIRING OF CONVECTION ACROSS THE ILM SC COUNTIES. IN ADDITION...THE SEA BREEZE AIDED BY OUTFLOW FROM ILM NC EARLIER CONVECTION...HAS PUSHED NEARLY 1 FULL COUNTY INLAND FROM THE ILM SC COAST. LOOK FOR THESE CLUSTERS OF CONVECTION TO CONTINUE TO PUSH SOUTH BY SOUTHWEST VIA LATEST STORM MOTIONS FROM HRLY PROGGED SOUNDINGS. WILL CONTINUE POPS FOR UP TO SEVERAL HRS AFTER SUNSET WITH CONVECTION EITHER DISSIPATING OR SLIDING SOUTH OF THE ILM CWA BY LATE THIS EVENING. THIS UPDATE WILL ALSO ADD A BIT MORE CLOUDINESS FOR SKY CONDITIONS FOR THE EVENING AND OVERNIGHT. CURRENT MIN TEMP GUIDANCE LOOKS AOK AND SEE NO TWEAKING NEEDED AT THIS TIME. PREVIOUS DISCUSSION............................................. AS OF 3 PM WEDNESDAY...A SURFACE TROUGH PUSHED OFFSHORE THIS MORNING AT ABOUT THE SAME TIME AS THE 500 MB TROUGH DID ALOFT. THIS ALLOWED A LIGHT BUT DEEP-LAYER NORTHERLY FLOW TO OVERSPREAD THE AREA. THE ACTUAL SURFACE COLD FRONT HAS LAGGED BOTH OF THESE FEATURES AND IS JUST NOW PRESSING INTO SOUTHEASTERN NORTH CAROLINA...ACCOMPANIED BY ENHANCED CUMULUS AND SCATTERED SHOWERS. WE EXPECT SHOWERS AND EVEN SOME THUNDERSTORMS TO INCREASE IN COVERAGE OVER THE NEXT COUPLE OF HOURS AS THE BOUNDARY PUSHES SOUTH INTO NORTHEASTERN SOUTH CAROLINA. BY 6 PM THE BEST CHANCES FOR RAIN SHOULD EXIST ALONG AND SOUTH OF A LINE FROM LAKE CITY TO BRITTONS NECK TO MYRTLE BEACH. THE NEW AIRMASS ADVECTING SOUTHWARD IS QUITE DISSIMILAR TO THE TROPICAL AIRMASS OF THE PAST SEVERAL DAYS: PRECIPITABLE WATER VALUES AROUND 1.6 INCHES CURRENTLY SHOULD FALL TO 1.0 INCH AFTER MIDNIGHT...AND TO 0.7 INCHES BY DAYBREAK THURSDAY. LOW PRESSURE WILL DEEPEN ALONG THE FRONT WELL OFFSHORE TONIGHT... WITH NORTH TO NORTHEASTERLY WINDS BRINGING A MILD AIRMASS SOUTH INTO THE CAROLINAS. 850 MB TEMPS DON`T BUDGE MUCH...BUT WEAK COOL ADVECTION IN THE SFC-900 MB LAYER WILL ALLOW LOWS TO FALL INTO THE LOWER TO MIDDLE 60S FOR MOST AREAS. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 3 PM WEDNESDAY...A COLD FRONT WILL BE OFF THE COAST AS THE FORECAST PERIOD BEGINS AND A LOW PRESSURE AREA WILL DEVELOP ALONG THE FRONT. THIS WILL INCREASE THE NORTHERLY WINDS OVER THE REGION AND COOLER AND DRIER AIR WILL SHIFT INTO THE AREA. HIGHS WILL BE IN THE LOWER 80S AND LOWS IN THE LOWER 60S. WITH THE DRIER AIR THE CHANCES OF PRECIPITATION ARE NIL. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... AS OF 3 PM WEDNESDAY...SURFACE HIGH PRESSURE NOSING IN FROM THE NORTHEAST WHILE OFFSHORE MID LEVEL TROUGH DEVELOPS OFF THE COAST FOR MUCH OF THE PERIOD. THIS LEADS TO A DEEP NORTHEASTERLY FLOW ACROSS THE COASTAL CAROLINAS FOR MOST OF THE PERIOD. TEMPERATURES WILL AVERAGE ROUGHLY A CATEGORY BELOW CLIMO BY DAY AND PERHAPS A FEW DEGREES MORE BY NIGHT...THERE COULD EVEN BE A FEW UPPER 50S WELL INLAND. THE SURFACE RIDGE BEGINS TO PROGRESS TO THE EAST BY TUESDAY TURNING THE FLOW FROM NE TO MORE EAST OR SOUTHEAST. THIS SHOULD LEAD TO SOME MOISTURE ADVECTION AND PERHAPS ISOLATED EARLY MORNING SHOWERS ALONG THE COAST. TEMPERATURES WILL ALSO TREND UPWARD SLIGHTLY. && .AVIATION /00Z WEDNESDAY THROUGH MONDAY/... AS OF 00Z...TERMINALS ARE CURRENTLY VFR. SANDWICHED BETWEEN DRIER MID-LEVEL AIR ADVECTING IN FROM THE NORTH FROM LBT TO THE WEST OF FLO...AND THE SEA BREEZE JUST INLAND OF THE COASTAL TERMINALS... SHOWERS AND THUNDERSTORMS ARE OCCURRING. THIS AREA OF ACTIVITY IS GRADUALLY DISSIPATING FROM NORTH TO SOUTH AS DRIER AIR FILTERS INTO NORTHERN PORTIONS OF THE AREA. EXCEPT FOR A SLIGHT CHANCE OF VCTS FROM ACTIVITY TO THE WEST OF MYR 00-01Z...EXPECT NO THUNDERSTORM ACTIVITY AT THE TERMINALS THIS EVENING. CONVECTION SHOULD MOVE SOUTH AND GRADUALLY DIE OFF OVER THE NEXT SEVERAL HOURS WITH LOSS OF DAY-TIME HEATING. AS HIGH PRESSURE BUILDS IN WITH DRYING LOW AND MID-LEVELS...VFR IS EXPECTED TO CONTINUE THROUGH THE OVERNIGHT HOURS. EAST TO SOUTHEAST WINDS AT THE COASTAL TERMINALS THIS EVENING WILL GRADUALLY BECOME NORTH-NORTHEAST BY MIDNIGHT. AFTER SUNRISE NORTH TO NORTHEAST WINDS CAN BE EXPECTED WITH OCCASIONAL GUSTS TO-25 20 KNOTS AT THE COASTAL TERMINALS. ENOUGH WRAP AROUND MOISTURE IN THE LOW-MID LEVELS FROM A LOW PRESSURE AREA OFFSHORE MAY ADVECT IN FROM THE NORTHEAST TO CONSTITUTE A LOW VFR CEILING AT TIMES DURING THE LATE MORNING AND AFTERNOON...ESPECIALLY AT THE COASTAL TERMINALS. THE CHANCE OF ANY SHOWERS APPEAR TOO LOW TO MENTION IN TAFS ATTM. EXTENDED OUTLOOK...MAINLY VFR THROUGH THE FORECAST PERIOD WITH NORTHEASTERLY WINDS. A CHANCE OF SHOWERS SUNDAY AND MONDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 745 PM WEDNESDAY...NNE-ENE WINDS WILL BECOME DOMINATE THIS EVENING AT 5 TO 10 KT...THEN FURTHER INCREASE TO 10 TO 15 KT OVERNIGHT. THIS A RESULT OF THE FRONT MOVING FURTHER SOUTH AND EAST FROM THE ILM COASTAL WATERS AS DECENT RIDGING FROM THE HIGH CENTERED OVER SE CANADA BECOMES MORE DOMINANT. SPEEDS COULD REACH AROUND 15 KT BY DAYBREAK FOR THE WATERS FROM CAPE FEAR NORTHWARD. OVERNIGHT SIGNIFICANT SEAS WILL RUN 2 TO 3 FT...EXCEPT UP TO 4 FT OFF CAPE FEAR. WIND DRIVEN WAVES WILL CONTINUE THE MORE DOMINANT PLAYER FOR SIG SEAS WITH DOMINANT PERIODS AROUND 6 SECONDS. THE BEST POTENTIAL FOR CONVECTION WILL BE THIS EVENING FOR THE NEAR SHORE WATERS SOUTH OF LITTLE RIVER INLET. .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 3 PM WEDNESDAY...A COLD FRONT WILL BE OFF THE COAST AS THE FORECAST PERIOD BEGINS AND A LOW PRESSURE AREA WILL DEVELOP ALONG THE FRONT. THIS WILL INCREASE THE NORTHERLY WINDS OVER THE REGION AND COOLER AND DRIER AIR WILL SHIFT INTO THE AREA. HIGHS WILL BE IN THE LOWER 80S AND LOWS IN THE LOWER 60S. WITH THE DRIER AIR THE CHANCES OF PRECIPITATION ARE NIL. LONG TERM /SATURDAY THROUGH SUNDAY/... AS OF 3 PM WEDNESDAY...RATHER UNCLIMATOLOGICAL NE FLOW TO BE IN PLACE THROUGH THE PERIOD. HIGH PRESSURE NOSED INTO THE CAROLINAS FROM THE NORTHEAST FOR MUCH OF THE TIME. IN THIS COAST- PARALLEL FLOW THERE MAY BE A CONSIDERABLE GRADIENT IN WAVE HEIGHT FROM THE COAST TO THE 20NM FORECAST ZONE BORDER...AND FUTURE FORECASTS WILL HAVE TO DETERMINE WHETHER SOME 6 FT SEAS WILL BE CLOSE ENOUGH TO WARRANT A SMALL CRAFT ADVISORY ON SATURDAY. A SLIGHT EASE IN THE GRADIENT TRANSLATING TO AN APPROXIMATE 5KT DROP IN SUSTAINED WIND SPEED FOR SUNDAY SHOULD PRECLUDE ANY ADVISORIES BUT SCEC HEADLINES ARE TOUGH TO RULE OUT EARLY ON. AN EASTWARD JOG OF THE HIGH ON MONDAY WILL WEAKEN THE WINDS EVEN FURTHER RESULTING IN A MORE PRONOUNCED ABATING OF THE SEAS. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ SYNOPSIS...HAWKINS NEAR TERM...DCH/TRA SHORT TERM...HAWKINS LONG TERM...MBB AVIATION...MRR
AREA FORECAST DISCUSSION
NWS RALEIGH NC
256 PM EDT TUE JUN 12 2012 .SYNOPSIS... A COLD FRONT WILL PUSH SLOWLY SOUTHEAST THROUGH THE REGION LATE TONIGHT AND WEDNESDAY...BRINGING COOLER AND MUCH DRIER CONDITIONS. && .NEAR TERM /THROUGH TONIGHT/... AS OF 230 PM TUESDAY... OVERVIEW: A WEAK MID-LEVEL TROUGH CENTERED OVER THE WESTERN CAROLINAS (NEAR I-77 PER 700 MB 15Z SPC MESOANALYSIS) WILL TRACK SLOWLY EASTWARD INTO THE CENTRAL CAROLINAS THIS AFTERNOON/EVENING...PROGRESSING TO THE CAROLINA COAST BY 12Z WED MORNING. IN THE LOWER LEVELS...A SFC-H85 REFLECTION ATTENDANT THE MID-LEVEL WAVE WILL ALSO PROGRESS EASTWARD INTO THE CENTRAL CAROLINAS. FURTHER UPSTREAM...A COLD FRONT EXTENDING SSW FROM THE GREAT LAKES INTO THE WESTERN OH/TN VALLEY AT 15Z THIS MORNING WILL PROGRESS INTO THE SOUTHERN APPALACHIANS BY 00Z THIS EVENING. THE FRONT WILL SLOW DOWN AND BECOME INCREASINGLY WEST-EAST ORIENTED TONIGHT...THEN PROGRESS SOUTH THROUGH THE AREA ON WED AS HIGH PRESSURE STRENGTHENS OVER THE GREAT LAKES AND NORTHERN MID-ATLANTIC. PRECIPITATION CHANCES: DESPITE A VERY MOIST BOUNDARY LAYER WITH SFC DEWPOINTS IN THE LOWER 70S...WEAK MID-LEVEL LAPSE RATES AND EXTENSIVE CLOUD COVER OVER THE AREA SHOULD TEMPER DIURNAL DESTABILIZATION THIS AFTERNOON ALONG/EAST OF HWY 1...WHERE 500-1000 J/KG OF MLCAPE IS PROGGED AT BEST. IN THE WESTERN PIEDMONT...LESS CLOUD COVER AND BETTER INSOLATION WILL LEAD TO STRONGER DIURNAL DESTABILIZATION...WITH MLCAPE VALUES PROGGED AT 1000-1500 J/KG. BASED ON SPC MESOANALYSIS AND THE LATEST OBSERVATIONAL DATA...THE LOW/MID-LEVEL TROUGH IN VICINITY OF I-77 OVER THE WESTERN CAROLINAS AT 15Z WILL BE THE PRIMARY FOCUSING MECHANISM FOR CONVECTION TODAY AS IT PROGRESSES EASTWARD INTO CENTRAL NC IN THE PRESENCE OF A TROPICAL (PWAT NEAR 2.00") AIRMASS. 15Z VWP DATA FROM SURROUNDING SITES ALREADY SHOW WESTERLY LOW-LEVEL FLOW AT GSP/RNK/CAE...SUGGESTING THE BEST LOW-LEVEL CONVERGENCE AND FOCUS FOR CONVECTION TODAY SHOULD REMAIN ALONG AND EAST OF HIGHWAY 1...AND WILL MAINTAIN CATEGORICAL (80%) PRECIPITATION CHANCES IN THAT AREA. FURTHER WEST THE FORECAST IS MORE UNCERTAIN. ALTHOUGH THE BEST CONVERGENCE WITH THE LOW/MID-LEVEL TROUGH IS ALREADY IN VICINITY OF HWY 1...15Z WV IMAGERY SHOWED A SHEAR AXIS PROGRESSING EASTWARD THROUGH EASTERN KY/CENTRAL TN...AND THE LATEST RAP MODEL DATA PROGS THIS FEATURE TO PROGRESS INTO THE MOUNTAINS AND FOOTHILLS LATER THIS AFTERNOON AND EVENING (IN VICINITY OF PEAK HEATING). ALTERNATELY...DIFFERENTIAL HEATING IN THE PRESENCE OF A VERY MOIST AIRMASS MAY LEAD TO THE DEVELOPMENT OF ISOLD/SCT CONVECTION IN THE MOUNTAINS EARLY THIS AFTERNOON...WHICH COULD PROGRESS EAST/SE INTO THE WESTERN PIEDMONT BY MID TO LATE AFTERNOON VIA 15 KT W/NW MID-LEVEL FLOW. THE 00-12Z HIGH-RES CONVECTION ALLOWING MODELS OFFER VARYING SOLUTIONS WITH REGARD TO CONVECTION THIS AFTERNOON... RANGING FROM LITTLE MORE THAN ISOLD CONVECTION IN THE WESTERN PIEDMONT TO THE DEVELOPMENT OF A SW-NE ORIENTED LINE OF CONVECTION FROM CLT-INT AT 20Z THAT PROGRESSES THROUGH ALL OF CENTRAL NC BY SUNSET. ADDITIONALLY...LARGE MCS`S UPSTREAM OF THE AREA LAST NIGHT MAY HAVE ALTERED THE MID-LEVELS IN A MANNER NOT CAPTURED WELL BY THE 00-06Z MODEL RUNS...ADDING FURTHER UNCERTAINTY TO THE PRECIP FORECAST. WITH THE ABOVE IN MIND...FEEL THAT IT WOULD BE UNWISE TO REDUCE PRECIP CHANCES MUCH BELOW WHAT HAS BEEN PREVIOUSLY ADVERTISED IN THE WESTERN PIEDMONT. AFTER SUNSET...EXPECT CONVECTION TO WEAKEN AND SHIFT SOUTHEAST IN CONCERT WITH THE MID-LEVEL TROUGH...WITH PRECIP CHANCES DECREASING AND ENDING FROM NW-SE BY OR SHORTLY AFTER MIDNIGHT AS A DRIER MID-LEVEL AIRMASS PROGRESSES INTO THE AREA. SEVERE/FLOODING THREAT: DO NOT ANTICIPATE A THREAT FOR AREA-WIDE FLOODING GIVEN A LACK OF WIDESPREAD HEAVY RAIN YESTERDAY (ISOLD AREAS GOT 1-2") AND 1-3 HR FLASH FLOOD GUIDANCE IN THE 2-4" RANGE IN MOST LOCATIONS (EXCLUDING URBAN AREAS). HOWEVER...GIVEN THE TROPICAL AIRMASS IN PLACE... RAINFALL RATES WITH CONVECTION THIS AFTERNOON WILL BE ON THE HIGH-END...AND A LOCALIZED THREAT FOR FLOODING WILL CERTAINLY BE PRESENT...PRIMARILY IN URBAN AREAS. ALTHOUGH MODERATE INSTABILITY WILL BE POSSIBLE IN THE WESTERN PIEDMONT THIS AFT/EVE...DEEP LAYER SHEAR IS PROGGED TO BE NO HIGHER THAN 15-20 KT...AND ORGANIZED CONVECTION IS NOT EXPECTED. RELATIVELY BETTER INSOLATION IN THE WESTERN PIEDMONT MAY YIELD 500-750 J/KG OF DCAPE THIS AFTERNOON...IN THE PRESENCE OF 1.50"+ PWAT VALUES. THIS COMBINATION OF PRECIP LOADING AND BOUNDARY LAYER EVAP COOLING COULD RESULT IN ISOLD SEVERE DOWNBURSTS IN THE WESTERN PIEDMONT BETWEEN 300-800 PM. TEMPERATURES: EXTENSIVE CLOUD COVER AND SHOWER ACTIVITY WILL KEEP HIGHS TODAY SIMILAR TO YESTERDAY...IN THE LOWER 80S...OR 81-85F. LOWS TONIGHT WILL PRIMARILY DEPEND ON THE PROGRESS OF THE COLD (DRY) FRONT APPROACHING THE AREA FROM THE NORTHWEST. THE BULK OF MODEL GUIDANCE AGREES THAT THE FRONT SHOULD MAKE PROGRESS INTO THE N/NW PIEDMONT BY SUNRISE WED...AND WILL INDICATE LOWS RANGING FROM THE MID/UPPER 60S N/NW TO ~70F SOUTHEAST. -VINCENT && .SHORT TERM /WEDNESDAY THROUGH FRIDAY/... AS OF 245 PM TUESDAY... WEDNESDAY: THE MID-LEVEL TROUGH TRACKING EASTWARD INTO CENTRAL NC TODAY IS PROGGED TO PROGRESS TO THE CAROLINA COAST BY 12Z WED...WITH A MUCH DRIER MID-LEVEL AIRMASS OVERSPREADING THE AREA. IN THE LOWER LEVELS...THE SW-NE ORIENTED COLD FRONT LOCATED OVER THE CENTRAL OH/TN VALLEY THIS AFTERNOON WILL BECOME MORE WEST-EAST ORIENTED AS IT MOVES INTO THE MID-ATLANTIC TONIGHT. THE FRONT WILL PROGRESS SOUTHWARD THROUGH CENTRAL NC DURING THE DAY WED AS HIGH PRESSURE STRENGTHENS OVER THE GREAT LAKES. THE LATEST MODEL GUIDANCE SHOWS THE LEADING EDGE OF THE FRONT (AND WIND SHIFT TO THE N/NE) OCCURRING AROUND OR SHORTLY AFTER SUNRISE WED MORNING...HOWEVER...MODEL GUIDANCE IS IN RELATIVELY GOOD AGREEMENT THAT THE BOUNDARY LAYER WILL REMAIN RELATIVELY MOIST THROUGH PEAK HEATING WED...WITH THE BULK OF THE DRIER AIR NOT ADVECTING INTO CENTRAL NC FROM THE NORTH/NE UNTIL THE LATE AFTERNOON/EVENING. FCST SOUNDINGS SHOW SFC DEWPOINTS IN THE MID 60S ALMOST EVERYWHERE...WITH UPPER 60S TO NEAR 70F IN SOUTH/SW PORTIONS OF THE AREA. GIVEN THE RESIDUAL MOIST BOUNDARY LAYER AND GOOD INSOLATION ASSOC/W DRIER MID-LEVELS...MLCAPE VALUES COULD REACH AS HIGH AS 1000-1500 J/KG DURING PEAK HEATING... PRIMARILY IN THE SANDHILLS/SW PIEDMONT. THOUGH THE BEST LOW-LEVEL CONVERGENCE SHOULD BE ALONG OR JUST OFFSHORE THE CAROLINA COAST WED AFTERNOON...MODEL GUIDANCE INDICATES SHORTWAVE ENERGY PROGRESSING INTO WESTERN PORTIONS OF THE STATE BY MID/LATE AFTERNOON. IT IS POSSIBLE THAT ISOLD CONVECTION COULD DEVELOP OVER PORTIONS OF THE AREA BETWEEN 21-00Z IF SHORTWAVE ENERGY ARRIVES DURING PEAK HEATING AND/OR PRIOR TO THE ADVECTION OF THE DRIER /MORE STABLE/ LOW-LEVEL AIRMASS FROM THE NORTH. AT THIS TIME THE SHORTWAVE ENERGY APPEARS TO ARRIVE A BIT TOO LATE...AND CONSIDERABLE DRY AIR ALOFT WOULD LIKELY ACT TO HINDER EVEN ISOLD DEVELOPMENT. WILL KEEP PRECIP CHANCES CONFINED TO A SLIGHT CHANCE SOUTH OF HWY 64 IN THE SANDHILLS/SW PIEDMONT DURING THE AFTERNOON. WITH MOSTLY SUNNY SKIES AND COLD ADVECTION OCCURRING CLOSER TOWARD SUNSET EXPECT HIGHS IN THE MID/UPPER 80S. -VINCENT WEDNESDAY NIGHT THROUGH FRIDAY: MUCH DRIER AND COOLER CONDITIONS ARRIVE WEDNESDAY NIGHT AND THURSDAY...LASTING THROUGH THE WEEKEND. THE MODELS ARE IN GOOD GENERAL AGREEMENT IN THE DEVELOPMENT OF A WESTERN ATLANTIC UPPER TROUGH WITH OUR REGION ON THE SUBSIDENCE SIDE OF THE TROUGH WEDNESDAY NIGHT THROUGH THE END OF THE WEEK. THE MUCH DRIER AIR WILL BE FELT WEDNESDAY NIGHT AND THURSDAY AS DEW POINTS FALL INTO THE 50S WITH THE NNE LOW LEVEL FLOW. THE SKIES ARE EXPECTED TO BE MOSTLY CLEAR WEDNESDAY NIGHT. SOME MIXING WILL CONTINUE WEDNESDAY NIGHT AS THE HIGH PRESSURE BUILDS SOUTHWARD DOWN THE EASTERN SEABOARD INTO NC/SC. LOWS MAY BE HELD UP AS WELL BY THE NE FLOW AT 5-10 MPH. WE WILL LEAN TOWARD THE WARMER NAM GUIDANCE...60-65 FOR LOWS. THURSDAY...MODELS ALSO SUGGEST A PERIOD OF CLOUDINESS WILL BE LIKELY AS THE NE FLOW ADVECTS ATLANTIC MOISTURE ACROSS EASTERN VA INTO CENTRAL NC DURING THE AFTERNOON AND EVENING. THE FORECAST SOUNDINGS INDICATE PARTLY SUNNY TO MOSTLY CLOUDY SKIES THROUGH THE AFTERNOON WITH HIGHS 75-82 (NE TO S). AS THE SURFACE HIGH PRESSURE STRENGTHENS AND MOVES TOWARD THE MID-ATLANTIC STATES THURSDAY INTO THURSDAY NIGHT...THE SKIES ARE EXPECTED TO BECOME MOSTLY CLEAR/MOSTLY SUNNY. LOWS WILL DIP INTO THE 55-62 RANGE THURSDAY MORNING...WITH HIGHS EXPECTED TO HOLD IN THE UPPER 70S TO LOWER 80S. THESE READINGS WILL BE 5-8 DEGREES BELOW THE MID JUNE NORMALS. -BADGETT && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... AS OF 220 PM TUESDAY... AN EXTENDED DRY AND COOL PATTERN FOR MID JUNE. THE SURFACE RIDGE ALONG THE EAST COAST IS FORECAST TO STRENGTHEN FRIDAY INTO THE WEEKEND WITH A CONTINUED SUPPLY OF COOL AND DRY AIR ADVECTION INTO NC. FRI-SUN SHOULD FEATURE MOSTLY CLEAR NIGHTS AND MOSTLY SUNNY DAYS WITH LOW HUMIDITY. LOWS WILL BE IN THE 50S TO AROUND 60 (5-10 DEGREES BELOW NORMAL). HIGHS WILL BE IN THE 77-82 RANGE... OR 5-8 DEGREES BELOW NORMAL). BY MONDAY AND TUESDAY... THERE IS A CHANCE OF SOME RETROGRESSION OF THE UPPER PATTERN WITH THE MID/UPPER LOW OVER THE WESTERN ATLANTIC POSSIBLY DRIFTING SLOWLY WESTWARD TOWARD THE EASTERN SEABOARD. STRONG RIDING IS EXPECTED TO OUR NW OVER THE OHIO VALLEY AND MIDWEST. THIS WILL LEAD TO A CONTINUED NORTHERLY FLOW ALOFT WITH DRY CONDITIONS. TEMPERATURES AND HUMIDITIES WILL MODERATE BACK CLOSER TO MID JUNE NORMALS... YET NOT QUITE ALL THE WAY BACK. LOWS 62-67 WITH HIGHS IN THE MID TO UPPER 80S. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... AS OF 150 PM TUESDAY... 24-HR TAF PERIOD: DIURNAL HEATING/MIXING HAS ALLOWED CEILINGS TO IMPROVE TO MVFR AT ALL TAF SITES...WITH THE 17Z INT TERMINAL REPORTING VFR CEILINGS. EXPECT CEILINGS TO GENERALLY RANGE FROM 2000-3500 FT THIS AFTERNOON GIVEN THE VERY MOIST AIRMASS IN PLACE...WITH MVFR/IFR CONDITIONS POSSIBLE BETWEEN 18-00Z AT ANY TAF SITE IN ASSOCIATION WITH SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS. GIVEN RELATIVELY HIGH CHANCES FOR PRECIPITATION...WILL INCLUDE A TEMPO GROUP FOR SHOWERS AND LOW-END MVFR CONDITIONS AT ALL TAF SITES DURING PEAK HEATING. WIND GUSTS UP TO 25-35 KT WILL BE POSSIBLE IN ASSOCIATION WITH ANY THUNDERSTORMS THIS AFTERNOON. THOUGH THE PROBABILITY IS LOW...ISOLATED CONVECTIVE WIND GUSTS AS HIGH AS 35-50 KT CANNOT BE RULED OUT AT THE INT/GSO TAF SITES BETWEEN 19-23Z. AFTER SUNSET... IFR CONDITIONS ASSOCIATED WITH FOG OR LOW CEILINGS WILL BE POSSIBLE AT ALL TAF SITES GIVEN A VERY MOIST BOUNDARY LAYER...LIGHT/VARIABLE OR CALM WINDS AND SOME EROSION OF CLOUD COVER AS THE MID-LEVELS BEGIN TO DRY OUT FROM THE WEST. A COLD (DRY) FRONT WILL APPROACH THE AREA FROM THE NORTHWEST AFTER MIDNIGHT AND PROGRESS INTO THE N/NW PIEDMONT BY SUNRISE. IT IS POSSIBLE THAT ENOUGH DRY AIR MAY ADVECT INTO THE INT/GSO TERMINALS TO IMPROVE CONDITIONS PRIOR TO SUNRISE... THOUGH UNCERTAINTY REMAINS HIGH. FURTHER SOUTH AND EAST AT THE RDU/RWI/FAY TERMINALS...MVFR OR IFR CONDITIONS ARE LIKELY TO PREVAIL THROUGH 12Z WED MORNING. ASIDE FROM LINGERING MVFR CEILINGS AT THE FAY/RWI TERMINALS WED MORNING...EXPECT VFR CONDITIONS BY THE END OF THE TAF PERIOD AS A DRIER AIRMASS PROGRESSES INTO THE AREA IN THE WAKE OF THE FRONT. LIGHT WEST/NW WINDS WILL BECOME NORTHEAST AT 10-15 KT IN THE WAKE OF THE FRONT...PRIMARILY AFTER 12Z WED. 18Z WEDNESDAY THROUGH SUNDAY: VFR CONDITIONS ARE GENERALLY EXPECTED BEHIND THE FRONT WEDNESDAY AFTERNOON/NIGHT AS A DRIER AIRMASS SETTLES INTO CENTRAL NC. HOWEVER...NORTHEAST FLOW OFF THE ATLANTIC MAY LEAD TO MVFR CEILINGS ACROSS THE AREA (PRIMARILY RDU/RWI/FAY TERMINALS) ON THURSDAY... THOUGH UNCERTAINTY REMAINS HIGH. NORTHEAST LOW-LEVEL FLOW WILL PERSIST INTO THE WEEKEND IN ASSOCIATION WITH UNSEASONABLY STRONG HIGH PRESSURE EXTENDING SOUTHWEST FROM NEW ENGLAND INTO THE MID-ATLANTIC/CAROLINAS. ALTHOUGH CHANCES FOR PRECIPITATION APPEAR LOW AT THIS TIME...EXPECT A POTENTIAL FOR MVFR CEILINGS FRIDAY THROUGH THE WEEKEND GIVEN NE/NNE LOW-LEVEL FLOW. -VINCENT && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...BADGETT NEAR TERM...VINCENT SHORT TERM...VINCENT/BADGETT LONG TERM...BADGETT AVIATION...VINCENT
AREA FORECAST DISCUSSION
NWS RALEIGH NC
220 PM EDT TUE JUN 12 2012 .SYNOPSIS... A COLD FRONT WILL PUSH SLOWLY SOUTHEAST THROUGH THE REGION LATE TONIGHT AND WEDNESDAY... BRINGING COOLER AND MUCH DRIER CONDITIONS. && .NEAR TERM /THROUGH WEDNESDAY/... AS OF 1230 PM TUESDAY... OVERVIEW: A WEAK MID-LEVEL TROUGH CENTERED OVER THE WESTERN CAROLINAS (NEAR I-77 PER 700 MB 15Z SPC MESOANALYSIS) WILL TRACK SLOWLY EASTWARD INTO THE CENTRAL CAROLINAS THIS AFTERNOON/EVENING...PROGRESSING TO THE CAROLINA COAST BY 12Z WED MORNING. IN THE LOWER LEVELS...A SFC-H85 REFLECTION ATTENDANT THE MID-LEVEL WAVE WILL ALSO PROGRESS EASTWARD INTO THE CENTRAL CAROLINAS. FURTHER UPSTREAM...A COLD FRONT EXTENDING SSW FROM THE GREAT LAKES INTO THE WESTERN OH/TN VALLEY AT 15Z THIS MORNING WILL PROGRESS INTO THE SOUTHERN APPALACHIANS BY 00Z THIS EVENING. THE FRONT WILL SLOW DOWN AND BECOME INCREASINGLY WEST-EAST ORIENTED TONIGHT...THEN PROGRESS SOUTH THROUGH THE AREA ON WED AS HIGH PRESSURE STRENGTHENS OVER THE GREAT LAKES AND NORTHERN MID-ATLANTIC. PRECIPITATION CHANCES: DESPITE A VERY MOIST BOUNDARY LAYER WITH SFC DEWPOINTS IN THE LOWER 70S...WEAK MID-LEVEL LAPSE RATES AND EXTENSIVE CLOUD COVER OVER THE AREA SHOULD TEMPER DIURNAL DESTABILIZATION THIS AFTERNOON ALONG/EAST OF HWY 1...WHERE 500-1000 J/KG OF MLCAPE IS PROGGED AT BEST. IN THE WESTERN PIEDMONT...LESS CLOUD COVER AND BETTER INSOLATION WILL LEAD TO STRONGER DIURNAL DESTABILIZATION...WITH MLCAPE VALUES PROGGED AT 1000-1500 J/KG. BASED ON SPC MESOANALYSIS AND THE LATEST OBSERVATIONAL DATA...THE LOW/MID-LEVEL TROUGH IN VICINITY OF I-77 OVER THE WESTERN CAROLINAS AT 15Z WILL BE THE PRIMARY FOCUSING MECHANISM FOR CONVECTION TODAY AS IT PROGRESSES EASTWARD INTO CENTRAL NC IN THE PRESENCE OF A TROPICAL (PWAT NEAR 2.00") AIRMASS. 15Z VWP DATA FROM SURROUNDING SITES ALREADY SHOW WESTERLY LOW-LEVEL FLOW AT GSP/RNK/CAE...SUGGESTING THE BEST LOW-LEVEL CONVERGENCE AND FOCUS FOR CONVECTION TODAY SHOULD REMAIN ALONG AND EAST OF HIGHWAY 1...AND WILL MAINTAIN CATEGORICAL (80%) PRECIPITATION CHANCES IN THAT AREA. FURTHER WEST THE FORECAST IS MORE UNCERTAIN. ALTHOUGH THE BEST CONVERGENCE WITH THE LOW/MID-LEVEL TROUGH IS ALREADY IN VICINITY OF HWY 1...15Z WV IMAGERY SHOWED A SHEAR AXIS PROGRESSING EASTWARD THROUGH EASTERN KY/CENTRAL TN...AND THE LATEST RAP MODEL DATA PROGS THIS FEATURE TO PROGRESS INTO THE MOUNTAINS AND FOOTHILLS LATER THIS AFTERNOON AND EVENING (IN VICINITY OF PEAK HEATING). ALTERNATELY...DIFFERENTIAL HEATING IN THE PRESENCE OF A VERY MOIST AIRMASS MAY LEAD TO THE DEVELOPMENT OF ISOLD/SCT CONVECTION IN THE MOUNTAINS EARLY THIS AFTERNOON...WHICH COULD PROGRESS EAST/SE INTO THE WESTERN PIEDMONT BY MID TO LATE AFTERNOON VIA 15 KT W/NW MID-LEVEL FLOW. THE 00Z AND 06Z HIGH-RES CONVECTION ALLOWING MODELS OFFER VARYING SOLUTIONS WITH REGARD TO CONVECTION THIS AFTERNOON... RANGING FROM LITTLE MORE THAN ISOLD CONVECTION IN THE WESTERN PIEDMONT TO THE DEVELOPMENT OF A SW-NE ORIENTED LINE OF CONVECTION FROM CLT-INT AT 20Z THAT PROGRESSES THROUGH ALL OF CENTRAL NC BY SUNSET. ADDITIONALLY...LARGE MCS`S UPSTREAM OF THE AREA LAST NIGHT MAY HAVE ALTERED THE MID-LEVELS IN A MANNER NOT CAPTURED WELL BY THE 00-06Z MODEL RUNS...ADDING FURTHER UNCERTAINTY TO THE PRECIP FORECAST. WITH THE ABOVE IN MIND...FEEL THAT IT WOULD BE UNWISE TO REDUCE PRECIP CHANCES MUCH BELOW WHAT HAS BEEN PREVIOUSLY ADVERTISED IN THE WESTERN PIEDMONT. AFTER SUNSET...EXPECT CONVECTION TO WEAKEN AND SHIFT SOUTHEAST IN CONCERT WITH THE MID-LEVEL TROUGH...WITH PRECIP CHANCES DECREASING AND ENDING FROM NW-SE BY OR SHORTLY AFTER MIDNIGHT AS A DRIER MID-LEVEL AIRMASS PROGRESSES INTO THE AREA. SEVERE/FLOODING THREAT: DO NOT ANTICIPATE A THREAT FOR AREA-WIDE FLOODING GIVEN A LACK OF WIDESPREAD HEAVY RAIN YESTERDAY (ISOLD AREAS GOT 1-2") AND 1-3 HR FLASH FLOOD GUIDANCE IN THE 2-4" RANGE IN MOST LOCATIONS (EXCLUDING URBAN AREAS). HOWEVER...GIVEN THE TROPICAL AIRMASS IN PLACE... RAINFALL RATES WITH CONVECTION THIS AFTERNOON WILL BE ON THE HIGH-END...AND A LOCALIZED THREAT FOR FLOODING WILL CERTAINLY BE PRESENT...PRIMARILY IN URBAN AREAS. ALTHOUGH MODERATE INSTABILITY WILL BE POSSIBLE IN THE WESTERN PIEDMONT THIS AFT/EVE...DEEP LAYER SHEAR IS PROGGED TO BE NO HIGHER THAN 15-20 KT...AND ORGANIZED CONVECTION IS NOT EXPECTED. RELATIVELY BETTER INSOLATION IN THE WESTERN PIEDMONT MAY YIELD 500-750 J/KG OF DCAPE THIS AFTERNOON...IN THE PRESENCE OF 1.50"+ PWAT VALUES. THIS COMBINATION OF PRECIP LOADING AND BOUNDARY LAYER EVAP COOLING COULD RESULT IN ISOLD SEVERE DOWNBURSTS IN THE WESTERN PIEDMONT BETWEEN 300-800 PM. TEMPERATURES: EXTENSIVE CLOUD COVER AND SHOWER ACTIVITY WILL KEEP HIGHS TODAY SIMILAR TO YESTERDAY...IN THE LOWER 80S...OR 81-85F. LOWS TONIGHT WILL PRIMARILY DEPEND ON THE PROGRESS OF THE COLD (DRY) FRONT APPROACHING THE AREA FROM THE NORTHWEST. THE BULK OF MODEL GUIDANCE AGREES THAT THE FRONT SHOULD MAKE PROGRESS INTO THE N/NW PIEDMONT BY SUNRISE WED...AND WILL INDICATE LOWS RANGING FROM THE MID/UPPER 60S N/NW TO ~70F SOUTHEAST. -VINCENT FOR WEDNESDAY: THE SURFACE TROUGH IS EXPECTED TO HAVE SHIFTED TO THE COASTAL CAROLINAS BY WEDNESDAY MORNING WITH MAINLY NORTHERLY FLOW AT 850 MB. THE MAIN COOL FRONT SHOULD EASE SLOWLY TO THE SSE INTO THE NORTHERN CWA DURING THE AFTERNOON AS A PORTION OF THE WEAKENING NORTHERN STREAM MID LEVEL SHORTWAVE DROPS SE TOWARD NC. PW VALUES ARE EXPECTED TO DROP BACK DOWN TO NEAR NORMAL VALUES AS DRIER AIR ADVECTS IN FROM THE NNW... MOST MARKEDLY IN THE MID-UPPER LEVELS... ALTHOUGH ELEVATED PW NEAR 1.5 INCHES WILL LIKELY REMAIN OVER THE SOUTHEAST CWA. AS A 60-70 KT SWRLY UPPER JET SHIFTS OVER THE DELMARVA AND NJ... WEAK UPPER DIVERGENCE WEDNESDAY AFTERNOON OVER SE NC WORKING ON THE LINGERING MOISTURE AND STEEPENING WET BULB LAPSE RATE MAY LEAD TO SCATTERED SHOWERS AND STORMS HERE... SO WILL LEAVE IN CHANCE POPS IN THE AFTERNOON WITH DRY CONDITIONS ELSEWHERE WHERE LOW LEVEL FLOW WILL BECOME NORTH-NORTHEASTERLY. AN ANTICIPATED LOW LEVEL DRY ADIABATIC LAPSE RATE SUGGESTS WARM HIGHS OF 84-88... WITH SCATTERED TO BROKEN CONVECTIVE CLOUDS AREAWIDE... MOST NUMEROUS ACROSS THE EAST AND SOUTH. -GIH && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/... AS OF 200 PM TUESDAY... MUCH DRIER AND COOLER CONDITIONS ARRIVE WEDNESDAY NIGHT AND THURSDAY... LASTING THROUGH THE WEEKEND. THE MODELS ARE IN GOOD GENERAL AGREEMENT IN THE DEVELOPMENT OF A WESTERN ATLANTIC UPPER TROUGH WITH OUR REGION ON THE SUBSIDENCE SIDE OF THE TROUGH WEDNESDAY NIGHT THROUGH THE END OF THE WEEK. THE MUCH DRIER AIR WILL BE FELT WEDNESDAY NIGHT AND THURSDAY AS DEW POINTS FALL INTO THE 50S WITH THE NNE LOW LEVEL FLOW. THE SKIES ARE EXPECTED TO BE MOSTLY CLEAR WEDNESDAY NIGHT. SOME MIXING WILL CONTINUE WEDNESDAY NIGHT AS THE HIGH PRESSURE BUILDS SOUTHWARD DOWN THE EASTERN SEABOARD INTO NC/SC. LOWS MAY BE HELD UP AS WELL BY THE NE FLOW AT 5-10 MPH. WE WILL LEAN TOWARD THE WARMER NAM GUIDANCE... 60-65 FOR LOWS. THURSDAY... MODELS ALSO SUGGEST A PERIOD OF CLOUDINESS WILL BE LIKELY AS THE NE FLOW ADVECTS ATLANTIC MOISTURE ACROSS EASTERN VA INTO CENTRAL NC DURING THE AFTERNOON AND EVENING. THE FORECAST SOUNDINGS INDICATE PARTLY SUNNY TO MOSTLY CLOUDY SKIES THROUGH THE AFTERNOON WITH HIGHS 75-82 (NE TO S). AS THE SURFACE HIGH PRESSURE STRENGTHENS AND MOVES TOWARD THE MID-ATLANTIC STATES THURSDAY INTO THURSDAY NIGHT... THE SKIES ARE EXPECTED TO BECOME MOSTLY CLEAR/MOSTLY SUNNY. LOWS WILL DIP INTO THE 55-62 RANGE THURSDAY MORNING... WITH HIGHS EXPECTED TO HOLD IN THE UPPER 70S TO LOWER 80S. THESE READINGS WILL BE 5-8 DEGREES BELOW THE MID JUNE NORMALS. && .LONG TERM /FRIDAY THROUGH TUESDAY/... AS OF 220 PM TUESDAY... AN EXTENDED DRY AND COOL PATTERN FOR MID JUNE. THE SURFACE RIDGE ALONG THE EAST COAST IS FORECAST TO STRENGTHEN FRIDAY INTO THE WEEKEND WITH A CONTINUED SUPPLY OF COOL AND DRY AIR ADVECTION INTO NC. FRI-SUN SHOULD FEATURE MOSTLY CLEAR NIGHTS AND MOSTLY SUNNY DAYS WITH LOW HUMIDITY. LOWS WILL BE IN THE 50S TO AROUND 60 (5-10 DEGREES BELOW NORMAL). HIGHS WILL BE IN THE 77-82 RANGE... OR 5-8 DEGREES BELOW NORMAL). BY MONDAY AND TUESDAY... THERE IS A CHANCE OF SOME RETROGRESSION OF THE UPPER PATTERN WITH THE MID/UPPER LOW OVER THE WESTERN ATLANTIC POSSIBLY DRIFTING SLOWLY WESTWARD TOWARD THE EASTERN SEABOARD. STRONG RIDING IS EXPECTED TO OUR NW OVER THE OHIO VALLEY AND MIDWEST. THIS WILL LEAD TO A CONTINUED NORTHERLY FLOW ALOFT WITH DRY CONDITIONS. TEMPERATURES AND HUMIDITIES WILL MODERATE BACK CLOSER TO MID JUNE NORMALS... YET NOT QUITE ALL THE WAY BACK. LOWS 62-67 WITH HIGHS IN THE MID TO UPPER 80S. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... AS OF 150 PM TUESDAY... 24-HR TAF PERIOD: DIURNAL HEATING/MIXING HAS ALLOWED CEILINGS TO IMPROVE TO MVFR AT ALL TAF SITES...WITH THE 17Z INT TERMINAL REPORTING VFR CEILINGS. EXPECT CEILINGS TO GENERALLY RANGE FROM 2000-3500 FT THIS AFTERNOON GIVEN THE VERY MOIST AIRMASS IN PLACE...WITH MVFR/IFR CONDITIONS POSSIBLE BETWEEN 18-00Z AT ANY TAF SITE IN ASSOCIATION WITH SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS. GIVEN RELATIVELY HIGH CHANCES FOR PRECIPITATION...WILL INCLUDE A TEMPO GROUP FOR SHOWERS AND LOW-END MVFR CONDITIONS AT ALL TAF SITES DURING PEAK HEATING. WIND GUSTS UP TO 25-35 KT WILL BE POSSIBLE IN ASSOCIATION WITH ANY THUNDERSTORMS THIS AFTERNOON. THOUGH THE PROBABILITY IS LOW...ISOLATED CONVECTIVE WIND GUSTS AS HIGH AS 35-50 KT CANNOT BE RULED OUT AT THE INT/GSO TAF SITES BETWEEN 19-23Z. AFTER SUNSET... IFR CONDITIONS ASSOCIATED WITH FOG OR LOW CEILINGS WILL BE POSSIBLE AT ALL TAF SITES GIVEN A VERY MOIST BOUNDARY LAYER...LIGHT/VARIABLE OR CALM WINDS AND SOME EROSION OF CLOUD COVER AS THE MID-LEVELS BEGIN TO DRY OUT FROM THE WEST. A COLD (DRY) FRONT WILL APPROACH THE AREA FROM THE NORTHWEST AFTER MIDNIGHT AND PROGRESS INTO THE N/NW PIEDMONT BY SUNRISE. IT IS POSSIBLE THAT ENOUGH DRY AIR MAY ADVECT INTO THE INT/GSO TERMINALS TO IMPROVE CONDITIONS PRIOR TO SUNRISE... THOUGH UNCERTAINTY REMAINS HIGH. FURTHER SOUTH AND EAST AT THE RDU/RWI/FAY TERMINALS...MVFR OR IFR CONDITIONS ARE LIKELY TO PREVAIL THROUGH 12Z WED MORNING. ASIDE FROM LINGERING MVFR CEILINGS AT THE FAY/RWI TERMINALS WED MORNING...EXPECT VFR CONDITIONS BY THE END OF THE TAF PERIOD AS A DRIER AIRMASS PROGRESSES INTO THE AREA IN THE WAKE OF THE FRONT. LIGHT WEST/NW WINDS WILL BECOME NORTHEAST AT 10-15 KT IN THE WAKE OF THE FRONT...PRIMARILY AFTER 12Z WED. 18Z WEDNESDAY THROUGH SUNDAY: VFR CONDITIONS ARE GENERALLY EXPECTED BEHIND THE FRONT WEDNESDAY AFTERNOON/NIGHT AS A DRIER AIRMASS SETTLES INTO CENTRAL NC. HOWEVER...NORTHEAST FLOW OFF THE ATLANTIC MAY LEAD TO MVFR CEILINGS ACROSS THE AREA (PRIMARILY RDU/RWI/FAY TERMINALS) ON THURSDAY... THOUGH UNCERTAINTY REMAINS HIGH. NORTHEAST LOW-LEVEL FLOW WILL PERSIST INTO THE WEEKEND IN ASSOCIATION WITH UNSEASONABLY STRONG HIGH PRESSURE EXTENDING SOUTHWEST FROM NEW ENGLAND INTO THE MID-ATLANTIC/CAROLINAS. ALTHOUGH CHANCES FOR PRECIPITATION APPEAR LOW AT THIS TIME...EXPECT A POTENTIAL FOR MVFR CEILINGS FRIDAY THROUGH THE WEEKEND GIVEN NE/NNE LOW-LEVEL FLOW. -VINCENT && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...BADGETT NEAR TERM...VINCENT/HARTFIELD SHORT TERM...BADGETT LONG TERM...BADGETT AVIATION...VINCENT
AREA FORECAST DISCUSSION
NWS RALEIGH NC
156 PM EDT TUE JUN 12 2012 .SYNOPSIS... A COLD FRONT WILL APPROACH FROM THE NORTHWEST TONIGHT...THEN PUSH SOUTH THROUGH THE AREA ON WEDNESDAY AS AN UPPER LEVEL DISTURBANCE PROGRESSES OFFSHORE. DRIER CONDITIONS ARE EXPECTED WEDNESDAY AFTERNOON THROUGH THE REMAINDER OF THE WORK WEEK. && .NEAR TERM /THROUGH WEDNESDAY/... AS OF 1230 PM TUESDAY... OVERVIEW: A WEAK MID-LEVEL TROUGH CENTERED OVER THE WESTERN CAROLINAS (NEAR I-77 PER 700 MB 15Z SPC MESOANALYSIS) WILL TRACK SLOWLY EASTWARD INTO THE CENTRAL CAROLINAS THIS AFTERNOON/EVENING...PROGRESSING TO THE CAROLINA COAST BY 12Z WED MORNING. IN THE LOWER LEVELS...A SFC-H85 REFLECTION ATTENDANT THE MID-LEVEL WAVE WILL ALSO PROGRESS EASTWARD INTO THE CENTRAL CAROLINAS. FURTHER UPSTREAM...A COLD FRONT EXTENDING SSW FROM THE GREAT LAKES INTO THE WESTERN OH/TN VALLEY AT 15Z THIS MORNING WILL PROGRESS INTO THE SOUTHERN APPALACHIANS BY 00Z THIS EVENING. THE FRONT WILL SLOW DOWN AND BECOME INCREASINGLY WEST-EAST ORIENTED TONIGHT...THEN PROGRESS SOUTH THROUGH THE AREA ON WED AS HIGH PRESSURE STRENGTHENS OVER THE GREAT LAKES AND NORTHERN MID-ATLANTIC. PRECIPITATION CHANCES: DESPITE A VERY MOIST BOUNDARY LAYER WITH SFC DEWPOINTS IN THE LOWER 70S...WEAK MID-LEVEL LAPSE RATES AND EXTENSIVE CLOUD COVER OVER THE AREA SHOULD TEMPER DIURNAL DESTABILIZATION THIS AFTERNOON ALONG/EAST OF HWY 1...WHERE 500-1000 J/KG OF MLCAPE IS PROGGED AT BEST. IN THE WESTERN PIEDMONT...LESS CLOUD COVER AND BETTER INSOLATION WILL LEAD TO STRONGER DIURNAL DESTABILIZATION...WITH MLCAPE VALUES PROGGED AT 1000-1500 J/KG. BASED ON SPC MESOANALYSIS AND THE LATEST OBSERVATIONAL DATA...THE LOW/MID-LEVEL TROUGH IN VICINITY OF I-77 OVER THE WESTERN CAROLINAS AT 15Z WILL BE THE PRIMARY FOCUSING MECHANISM FOR CONVECTION TODAY AS IT PROGRESSES EASTWARD INTO CENTRAL NC IN THE PRESENCE OF A TROPICAL (PWAT NEAR 2.00") AIRMASS. 15Z VWP DATA FROM SURROUNDING SITES ALREADY SHOW WESTERLY LOW-LEVEL FLOW AT GSP/RNK/CAE...SUGGESTING THE BEST LOW-LEVEL CONVERGENCE AND FOCUS FOR CONVECTION TODAY SHOULD REMAIN ALONG AND EAST OF HIGHWAY 1...AND WILL MAINTAIN CATEGORICAL (80%) PRECIPITATION CHANCES IN THAT AREA. FURTHER WEST THE FORECAST IS MORE UNCERTAIN. ALTHOUGH THE BEST CONVERGENCE WITH THE LOW/MID-LEVEL TROUGH IS ALREADY IN VICINITY OF HWY 1...15Z WV IMAGERY SHOWED A SHEAR AXIS PROGRESSING EASTWARD THROUGH EASTERN KY/CENTRAL TN...AND THE LATEST RAP MODEL DATA PROGS THIS FEATURE TO PROGRESS INTO THE MOUNTAINS AND FOOTHILLS LATER THIS AFTERNOON AND EVENING (IN VICINITY OF PEAK HEATING). ALTERNATELY...DIFFERENTIAL HEATING IN THE PRESENCE OF A VERY MOIST AIRMASS MAY LEAD TO THE DEVELOPMENT OF ISOLD/SCT CONVECTION IN THE MOUNTAINS EARLY THIS AFTERNOON...WHICH COULD PROGRESS EAST/SE INTO THE WESTERN PIEDMONT BY MID TO LATE AFTERNOON VIA 15 KT W/NW MID-LEVEL FLOW. THE 00Z AND 06Z HIGH-RES CONVECTION ALLOWING MODELS OFFER VARYING SOLUTIONS WITH REGARD TO CONVECTION THIS AFTERNOON... RANGING FROM LITTLE MORE THAN ISOLD CONVECTION IN THE WESTERN PIEDMONT TO THE DEVELOPMENT OF A SW-NE ORIENTED LINE OF CONVECTION FROM CLT-INT AT 20Z THAT PROGRESSES THROUGH ALL OF CENTRAL NC BY SUNSET. ADDITIONALLY...LARGE MCS`S UPSTREAM OF THE AREA LAST NIGHT MAY HAVE ALTERED THE MID-LEVELS IN A MANNER NOT CAPTURED WELL BY THE 00-06Z MODEL RUNS...ADDING FURTHER UNCERTAINTY TO THE PRECIP FORECAST. WITH THE ABOVE IN MIND...FEEL THAT IT WOULD BE UNWISE TO REDUCE PRECIP CHANCES MUCH BELOW WHAT HAS BEEN PREVIOUSLY ADVERTISED IN THE WESTERN PIEDMONT. AFTER SUNSET...EXPECT CONVECTION TO WEAKEN AND SHIFT SOUTHEAST IN CONCERT WITH THE MID-LEVEL TROUGH...WITH PRECIP CHANCES DECREASING AND ENDING FROM NW-SE BY OR SHORTLY AFTER MIDNIGHT AS A DRIER MID-LEVEL AIRMASS PROGRESSES INTO THE AREA. SEVERE/FLOODING THREAT: DO NOT ANTICIPATE A THREAT FOR AREA-WIDE FLOODING GIVEN A LACK OF WIDESPREAD HEAVY RAIN YESTERDAY (ISOLD AREAS GOT 1-2") AND 1-3 HR FLASH FLOOD GUIDANCE IN THE 2-4" RANGE IN MOST LOCATIONS (EXCLUDING URBAN AREAS). HOWEVER...GIVEN THE TROPICAL AIRMASS IN PLACE... RAINFALL RATES WITH CONVECTION THIS AFTERNOON WILL BE ON THE HIGH-END...AND A LOCALIZED THREAT FOR FLOODING WILL CERTAINLY BE PRESENT...PRIMARILY IN URBAN AREAS. ALTHOUGH MODERATE INSTABILITY WILL BE POSSIBLE IN THE WESTERN PIEDMONT THIS AFT/EVE...DEEP LAYER SHEAR IS PROGGED TO BE NO HIGHER THAN 15-20 KT...AND ORGANIZED CONVECTION IS NOT EXPECTED. RELATIVELY BETTER INSOLATION IN THE WESTERN PIEDMONT MAY YIELD 500-750 J/KG OF DCAPE THIS AFTERNOON...IN THE PRESENCE OF 1.50"+ PWAT VALUES. THIS COMBINATION OF PRECIP LOADING AND BOUNDARY LAYER EVAP COOLING COULD RESULT IN ISOLD SEVERE DOWNBURSTS IN THE WESTERN PIEDMONT BETWEEN 300-800 PM. TEMPERATURES: EXTENSIVE CLOUD COVER AND SHOWER ACTIVITY WILL KEEP HIGHS TODAY SIMILAR TO YESTERDAY...IN THE LOWER 80S...OR 81-85F. LOWS TONIGHT WILL PRIMARILY DEPEND ON THE PROGRESS OF THE COLD (DRY) FRONT APPROACHING THE AREA FROM THE NORTHWEST. THE BULK OF MODEL GUIDANCE AGREES THAT THE FRONT SHOULD MAKE PROGRESS INTO THE N/NW PIEDMONT BY SUNRISE WED...AND WILL INDICATE LOWS RANGING FROM THE MID/UPPER 60S N/NW TO ~70F SOUTHEAST. -VINCENT FOR WEDNESDAY: THE SURFACE TROUGH IS EXPECTED TO HAVE SHIFTED TO THE COASTAL CAROLINAS BY WEDNESDAY MORNING WITH MAINLY NORTHERLY FLOW AT 850 MB. THE MAIN COOL FRONT SHOULD EASE SLOWLY TO THE SSE INTO THE NORTHERN CWA DURING THE AFTERNOON AS A PORTION OF THE WEAKENING NORTHERN STREAM MID LEVEL SHORTWAVE DROPS SE TOWARD NC. PW VALUES ARE EXPECTED TO DROP BACK DOWN TO NEAR NORMAL VALUES AS DRIER AIR ADVECTS IN FROM THE NNW... MOST MARKEDLY IN THE MID-UPPER LEVELS... ALTHOUGH ELEVATED PW NEAR 1.5 INCHES WILL LIKELY REMAIN OVER THE SOUTHEAST CWA. AS A 60-70 KT SWRLY UPPER JET SHIFTS OVER THE DELMARVA AND NJ... WEAK UPPER DIVERGENCE WEDNESDAY AFTERNOON OVER SE NC WORKING ON THE LINGERING MOISTURE AND STEEPENING WET BULB LAPSE RATE MAY LEAD TO SCATTERED SHOWERS AND STORMS HERE... SO WILL LEAVE IN CHANCE POPS IN THE AFTERNOON WITH DRY CONDITIONS ELSEWHERE WHERE LOW LEVEL FLOW WILL BECOME NORTH-NORTHEASTERLY. AN ANTICIPATED LOW LEVEL DRY ADIABATIC LAPSE RATE SUGGESTS WARM HIGHS OF 84-88... WITH SCATTERED TO BROKEN CONVECTIVE CLOUDS AREAWIDE... MOST NUMEROUS ACROSS THE EAST AND SOUTH. -GIH && .SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/... AS OF 255 AM TUESDAY... A COLD FRONT...ATTENDANT TO A WEAK...SOUTHWARD DRIFTING SURFACE LOW JUST OFFSHORE...WILL PUSH SOUTH THROUGH CENTRAL NC BY THURSDAY MORNING. HIGH PRESSURE WILL SET UP OVER EASTERN CANADA AND EXTEND SOUTH ALONG THE EAST COAST WHILE AN UPPER LEVEL RIDGE BUILDS FROM THE DEEP SOUTH TO THE MIDWEST. FORECAST SOUNDINGS SHOW ENOUGH OF A NORTHEASTERLY LOW LEVEL FETCH FOR SOME STRATUS THURSDAY MORNING...ESPECIALLY OVER THE COASTAL PLAIN. DESPITE AN INITIAL SURGE OF DRIER DEWPOINTS...WHICH ARE CURRENTLY IN THE UPEPR 40S OVER THE NORTHERN PLAINS...GUIDANCE SHOWS A STRONG RECOVERY DURING THE DAY WITH DEWPOINTS IN THE LOWER 60S. HOWEVER...MUCH DRIER MID LEVEL AIR AND STRENGTHENING SUBSIDENCE SHOULD PRECLUDE ANY SHOWERS OR STORMS. LOW LEVEL THICKNESSES ARE FORECAST TO FALL BELOW 1400M...TO AS LOW AS 1385M BASED ON THE GFS...LEADING TO HIGHS IN THE LOW TO MID 80S. PATCHY STRATUS COULD BE POSSIBLE AGAIN THURSDAY NIGHT...THROUGH THE STRENGTHENING SURFACE RIDGE AXIS MAY HELP TO KEEP STRATUS SUPPRESSED CLOSER TO THE COAST. LOWS IN THE LOWER 60S. && .LONG TERM /FRIDAY THROUGH MONDAY/... AS OF 255 AM TUESDAY... A PERSISTENT UPPER LOW OVER THE NORTH ATLANTIC WILL LEAD TO FURTHER AMPLIFICATION OF AN UPPER RIDGE FROM THE LOW MS VALLEY TO THE GREAT LAKES...WITH CENTRAL NC SANDWICHED BETWEEN THE TWO WAVE FEATURES. THE SURFACE RIDGE AXIS ALONG THE EAST COAST IS FORECAST TO STRENGTHEN FRIDAY AND SATURDAY WITH DRIER AIR SETTLING SOUTH INTO THE CAROLINAS. THE COOLING TREND EXPECTED TO BEGIN THURSDAY WILL CONTINUE AS LOW LEVEL THICKNESSES ARE PROGGED TO FALL SLIGHTLY EACH DAY....LEADING TO FORECAST HIGHS IN THE LOWER 80S BOTH DAYS. MODELS THEN DIVERGE SLIGHTLY AS THE ECMWF SHOWS THE UPEPR RIDGE WEAKENING MORE RAPIDLY...WITH MCS ACTIVITY TRAVERSING THE OH VALLEY LATE SUNDAY INTO MONDAY. THE GFS HAS A STRONGER UPPER RIDGE WEST OF THE MOUNTAINS...BUT ALLOWS SOME ENERGY ON THE WESTERN PERIPHERY OF THE NORTH ATLANTIC LOW TO DRIFT SOUTHWESTWARD ALONG THE COAST. WITH NO CLEAR SIGNAL AS TO WHICH FEATURE WILL BECOME DOMINANT...AT LEAST THROUGH MONDAY...WE WILL KEEP THE FORECAST DRY WITH A SLIGHT RECOVERY OF TEMPS SUNDAY AND MONDAY. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... AS OF 150 PM TUESDAY... 24-HR TAF PERIOD: DIURNAL HEATING/MIXING HAS ALLOWED CEILINGS TO IMPROVE TO MVFR AT ALL TAF SITES...WITH THE 17Z INT TERMINAL REPORTING VFR CEILINGS. EXPECT CEILINGS TO GENERALLY RANGE FROM 2000-3500 FT THIS AFTERNOON GIVEN THE VERY MOIST AIRMASS IN PLACE...WITH MVFR/IFR CONDITIONS POSSIBLE BETWEEN 18-00Z AT ANY TAF SITE IN ASSOCIATION WITH SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS. GIVEN RELATIVELY HIGH CHANCES FOR PRECIPITATION...WILL INCLUDE A TEMPO GROUP FOR SHOWERS AND LOW-END MVFR CONDITIONS AT ALL TAF SITES DURING PEAK HEATING. WIND GUSTS UP TO 25-35 KT WILL BE POSSIBLE IN ASSOCIATION WITH ANY THUNDERSTORMS THIS AFTERNOON. THOUGH THE PROBABILITY IS LOW...ISOLATED CONVECTIVE WIND GUSTS AS HIGH AS 35-50 KT CANNOT BE RULED OUT AT THE INT/GSO TAF SITES BETWEEN 19-23Z. AFTER SUNSET... IFR CONDITIONS ASSOCIATED WITH FOG OR LOW CEILINGS WILL BE POSSIBLE AT ALL TAF SITES GIVEN A VERY MOIST BOUNDARY LAYER...LIGHT/VARIABLE OR CALM WINDS AND SOME EROSION OF CLOUD COVER AS THE MID-LEVELS BEGIN TO DRY OUT FROM THE WEST. A COLD (DRY) FRONT WILL APPROACH THE AREA FROM THE NORTHWEST AFTER MIDNIGHT AND PROGRESS INTO THE N/NW PIEDMONT BY SUNRISE. IT IS POSSIBLE THAT ENOUGH DRY AIR MAY ADVECT INTO THE INT/GSO TERMINALS TO IMPROVE CONDITIONS PRIOR TO SUNRISE... THOUGH UNCERTAINTY REMAINS HIGH. FURTHER SOUTH AND EAST AT THE RDU/RWI/FAY TERMINALS...MVFR OR IFR CONDITIONS ARE LIKELY TO PREVAIL THROUGH 12Z WED MORNING. ASIDE FROM LINGERING MVFR CEILINGS AT THE FAY/RWI TERMINALS WED MORNING...EXPECT VFR CONDITIONS BY THE END OF THE TAF PERIOD AS A DRIER AIRMASS PROGRESSES INTO THE AREA IN THE WAKE OF THE FRONT. LIGHT WEST/NW WINDS WILL BECOME NORTHEAST AT 10-15 KT IN THE WAKE OF THE FRONT...PRIMARILY AFTER 12Z WED. 18Z WEDNESDAY THROUGH SUNDAY: VFR CONDITIONS ARE GENERALLY EXPECTED BEHIND THE FRONT WEDNESDAY AFTERNOON/NIGHT AS A DRIER AIRMASS SETTLES INTO CENTRAL NC. HOWEVER...NORTHEAST FLOW OFF THE ATLANTIC MAY LEAD TO MVFR CEILINGS ACROSS THE AREA (PRIMARILY RDU/RWI/FAY TERMINALS) ON THURSDAY... THOUGH UNCERTAINTY REMAINS HIGH. NORTHEAST LOW-LEVEL FLOW WILL PERSIST INTO THE WEEKEND IN ASSOCIATION WITH UNSEASONABLY STRONG HIGH PRESSURE EXTENDING SOUTHWEST FROM NEW ENGLAND INTO THE MID-ATLANTIC/CAROLINAS. ALTHOUGH CHANCES FOR PRECIPITATION APPEAR LOW AT THIS TIME...EXPECT A POTENTIAL FOR MVFR CEILINGS FRIDAY THROUGH THE WEEKEND GIVEN NE/NNE LOW-LEVEL FLOW. -VINCENT && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...VINCENT NEAR TERM...VINCENT/GIH SHORT TERM...SMITH LONG TERM...SMITH AVIATION...VINCENT
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1236 PM EDT TUE JUN 12 2012 .SYNOPSIS... A SLOW MOVING STORM SYSTEM LOCATED JUST TO OUR WEST THIS MORNING WILL BRING NUMEROUS SHOWERS AND A FEW THUNDERSTORMS TO OUR AREA TODAY. THIS STORM SYSTEM WILL MOVE THROUGH THE REGION LATE TONIGHT... BRINGING DRIER WEATHER FOR WEDNESDAY INTO FRIDAY. && .NEAR TERM /THROUGH WEDNESDAY/... AS OF 1230 PM TUESDAY... OVERVIEW: A WEAK MID-LEVEL TROUGH CENTERED OVER THE WESTERN CAROLINAS (NEAR I-77 PER 700 MB 15Z SPC MESOANALYSIS) WILL TRACK SLOWLY EASTWARD INTO THE CENTRAL CAROLINAS THIS AFTERNOON/EVENING...PROGRESSING TO THE CAROLINA COAST BY 12Z WED MORNING. IN THE LOWER LEVELS...A SFC-H85 REFLECTION ATTENDANT THE MID-LEVEL WAVE WILL ALSO PROGRESS EASTWARD INTO THE CENTRAL CAROLINAS. FURTHER UPSTREAM...A COLD FRONT EXTENDING SSW FROM THE GREAT LAKES INTO THE WESTERN OH/TN VALLEY AT 15Z THIS MORNING WILL PROGRESS INTO THE SOUTHERN APPALACHIANS BY 00Z THIS EVENING. THE FRONT WILL SLOW DOWN AND BECOME INCREASINGLY WEST-EAST ORIENTED TONIGHT...THEN PROGRESS SOUTH THROUGH THE AREA ON WED AS HIGH PRESSURE STRENGTHENS OVER THE GREAT LAKES AND NORTHERN MID-ATLANTIC. PRECIPITATION CHANCES: DESPITE A VERY MOIST BOUNDARY LAYER WITH SFC DEWPOINTS IN THE LOWER 70S...WEAK MID-LEVEL LAPSE RATES AND EXTENSIVE CLOUD COVER OVER THE AREA SHOULD TEMPER DIURNAL DESTABILIZATION THIS AFTERNOON ALONG/EAST OF HWY 1...WHERE 500-1000 J/KG OF MLCAPE IS PROGGED AT BEST. IN THE WESTERN PIEDMONT...LESS CLOUD COVER AND BETTER INSOLATION WILL LEAD TO STRONGER DIURNAL DESTABILIZATION...WITH MLCAPE VALUES PROGGED AT 1000-1500 J/KG. BASED ON SPC MESOANALYSIS AND THE LATEST OBSERVATIONAL DATA...THE LOW/MID-LEVEL TROUGH IN VICINITY OF I-77 OVER THE WESTERN CAROLINAS AT 15Z WILL BE THE PRIMARY FOCUSING MECHANISM FOR CONVECTION TODAY AS IT PROGRESSES EASTWARD INTO CENTRAL NC IN THE PRESENCE OF A TROPICAL (PWAT NEAR 2.00") AIRMASS. 15Z VWP DATA FROM SURROUNDING SITES ALREADY SHOW WESTERLY LOW-LEVEL FLOW AT GSP/RNK/CAE...SUGGESTING THE BEST LOW-LEVEL CONVERGENCE AND FOCUS FOR CONVECTION TODAY SHOULD REMAIN ALONG AND EAST OF HIGHWAY 1...AND WILL MAINTAIN CATEGORICAL (80%) PRECIPITATION CHANCES IN THAT AREA. FURTHER WEST THE FORECAST IS MORE UNCERTAIN. ALTHOUGH THE BEST CONVERGENCE WITH THE LOW/MID-LEVEL TROUGH IS ALREADY IN VICINITY OF HWY 1...15Z WV IMAGERY SHOWED A SHEAR AXIS PROGRESSING EASTWARD THROUGH EASTERN KY/CENTRAL TN...AND THE LATEST RAP MODEL DATA PROGS THIS FEATURE TO PROGRESS INTO THE MOUNTAINS AND FOOTHILLS LATER THIS AFTERNOON AND EVENING (IN VICINITY OF PEAK HEATING). ALTERNATELY...DIFFERENTIAL HEATING IN THE PRESENCE OF A VERY MOIST AIRMASS MAY LEAD TO THE DEVELOPMENT OF ISOLD/SCT CONVECTION IN THE MOUNTAINS EARLY THIS AFTERNOON...WHICH COULD PROGRESS EAST/SE INTO THE WESTERN PIEDMONT BY MID TO LATE AFTERNOON VIA 15 KT W/NW MID-LEVEL FLOW. THE 00Z AND 06Z HIGH-RES CONVECTION ALLOWING MODELS OFFER VARYING SOLUTIONS WITH REGARD TO CONVECTION THIS AFTERNOON... RANGING FROM LITTLE MORE THAN ISOLD CONVECTION IN THE WESTERN PIEDMONT TO THE DEVELOPMENT OF A SW-NE ORIENTED LINE OF CONVECTION FROM CLT-INT AT 20Z THAT PROGRESSES THROUGH ALL OF CENTRAL NC BY SUNSET. ADDITIONALLY...LARGE MCS`S UPSTREAM OF THE AREA LAST NIGHT MAY HAVE ALTERED THE MID-LEVELS IN A MANNER NOT CAPTURED WELL BY THE 00-06Z MODEL RUNS...ADDING FURTHER UNCERTAINTY TO THE PRECIP FORECAST. WITH THE ABOVE IN MIND...FEEL THAT IT WOULD BE UNWISE TO REDUCE PRECIP CHANCES MUCH BELOW WHAT HAS BEEN PREVIOUSLY ADVERTISED IN THE WESTERN PIEDMONT. AFTER SUNSET...EXPECT CONVECTION TO WEAKEN AND SHIFT SOUTHEAST IN CONCERT WITH THE MID-LEVEL TROUGH...WITH PRECIP CHANCES DECREASING AND ENDING FROM NW-SE BY OR SHORTLY AFTER MIDNIGHT AS A DRIER MID-LEVEL AIRMASS PROGRESSES INTO THE AREA. SEVERE/FLOODING THREAT: DO NOT ANTICIPATE A THREAT FOR AREA-WIDE FLOODING GIVEN A LACK OF WIDESPREAD HEAVY RAIN YESTERDAY (ISOLD AREAS GOT 1-2") AND 1-3 HR FLASH FLOOD GUIDANCE IN THE 2-4" RANGE IN MOST LOCATIONS (EXCLUDING URBAN AREAS). HOWEVER...GIVEN THE TROPICAL AIRMASS IN PLACE... RAINFALL RATES WITH CONVECTION THIS AFTERNOON WILL BE ON THE HIGH-END...AND A LOCALIZED THREAT FOR FLOODING WILL CERTAINLY BE PRESENT...PRIMARILY IN URBAN AREAS. ALTHOUGH MODERATE INSTABILITY WILL BE POSSIBLE IN THE WESTERN PIEDMONT THIS AFT/EVE...DEEP LAYER SHEAR IS PROGGED TO BE NO HIGHER THAN 15-20 KT...AND ORGANIZED CONVECTION IS NOT EXPECTED. RELATIVELY BETTER INSOLATION IN THE WESTERN PIEDMONT MAY YIELD 500-750 J/KG OF DCAPE THIS AFTERNOON...IN THE PRESENCE OF 1.50"+ PWAT VALUES. THIS COMBINATION OF PRECIP LOADING AND BOUNDARY LAYER EVAP COOLING COULD RESULT IN ISOLD SEVERE DOWNBURSTS IN THE WESTERN PIEDMONT BETWEEN 300-800 PM. TEMPERATURES: EXTENSIVE CLOUD COVER AND SHOWER ACTIVITY WILL KEEP HIGHS TODAY SIMILAR TO YESTERDAY...IN THE LOWER 80S...OR 81-85F. LOWS TONIGHT WILL PRIMARILY DEPEND ON THE PROGRESS OF THE COLD (DRY) FRONT APPROACHING THE AREA FROM THE NORTHWEST. THE BULK OF MODEL GUIDANCE AGREES THAT THE FRONT SHOULD MAKE PROGRESS INTO THE N/NW PIEDMONT BY SUNRISE WED...AND WILL INDICATE LOWS RANGING FROM THE MID/UPPER 60S N/NW TO ~70F SOUTHEAST. -VINCENT FOR WEDNESDAY: THE SURFACE TROUGH IS EXPECTED TO HAVE SHIFTED TO THE COASTAL CAROLINAS BY WEDNESDAY MORNING WITH MAINLY NORTHERLY FLOW AT 850 MB. THE MAIN COOL FRONT SHOULD EASE SLOWLY TO THE SSE INTO THE NORTHERN CWA DURING THE AFTERNOON AS A PORTION OF THE WEAKENING NORTHERN STREAM MID LEVEL SHORTWAVE DROPS SE TOWARD NC. PW VALUES ARE EXPECTED TO DROP BACK DOWN TO NEAR NORMAL VALUES AS DRIER AIR ADVECTS IN FROM THE NNW... MOST MARKEDLY IN THE MID-UPPER LEVELS... ALTHOUGH ELEVATED PW NEAR 1.5 INCHES WILL LIKELY REMAIN OVER THE SOUTHEAST CWA. AS A 60-70 KT SWRLY UPPER JET SHIFTS OVER THE DELMARVA AND NJ... WEAK UPPER DIVERGENCE WEDNESDAY AFTERNOON OVER SE NC WORKING ON THE LINGERING MOISTURE AND STEEPENING WET BULB LAPSE RATE MAY LEAD TO SCATTERED SHOWERS AND STORMS HERE... SO WILL LEAVE IN CHANCE POPS IN THE AFTERNOON WITH DRY CONDITIONS ELSEWHERE WHERE LOW LEVEL FLOW WILL BECOME NORTH-NORTHEASTERLY. AN ANTICIPATED LOW LEVEL DRY ADIABATIC LAPSE RATE SUGGESTS WARM HIGHS OF 84-88... WITH SCATTERED TO BROKEN CONVECTIVE CLOUDS AREAWIDE... MOST NUMEROUS ACROSS THE EAST AND SOUTH. -GIH && .SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/... AS OF 255 AM TUESDAY... A COLD FRONT...ATTENDANT TO A WEAK...SOUTHWARD DRIFTING SURFACE LOW JUST OFFSHORE...WILL PUSH SOUTH THROUGH CENTRAL NC BY THURSDAY MORNING. HIGH PRESSURE WILL SET UP OVER EASTERN CANADA AND EXTEND SOUTH ALONG THE EAST COAST WHILE AN UPPER LEVEL RIDGE BUILDS FROM THE DEEP SOUTH TO THE MIDWEST. FORECAST SOUNDINGS SHOW ENOUGH OF A NORTHEASTERLY LOW LEVEL FETCH FOR SOME STRATUS THURSDAY MORNING...ESPECIALLY OVER THE COASTAL PLAIN. DESPITE AN INITIAL SURGE OF DRIER DEWPOINTS...WHICH ARE CURRENTLY IN THE UPEPR 40S OVER THE NORTHERN PLAINS...GUIDANCE SHOWS A STRONG RECOVERY DURING THE DAY WITH DEWPOINTS IN THE LOWER 60S. HOWEVER...MUCH DRIER MID LEVEL AIR AND STRENGTHENING SUBSIDENCE SHOULD PRECLUDE ANY SHOWERS OR STORMS. LOW LEVEL THICKNESSES ARE FORECAST TO FALL BELOW 1400M...TO AS LOW AS 1385M BASED ON THE GFS...LEADING TO HIGHS IN THE LOW TO MID 80S. PATCHY STRATUS COULD BE POSSIBLE AGAIN THURSDAY NIGHT...THROUGH THE STRENGTHENING SURFACE RIDGE AXIS MAY HELP TO KEEP STRATUS SUPPRESSED CLOSER TO THE COAST. LOWS IN THE LOWER 60S. && .LONG TERM /FRIDAY THROUGH MONDAY/... AS OF 255 AM TUESDAY... A PERSISTENT UPPER LOW OVER THE NORTH ATLANTIC WILL LEAD TO FURTHER AMPLIFICATION OF AN UPPER RIDGE FROM THE LOW MS VALLEY TO THE GREAT LAKES...WITH CENTRAL NC SANDWICHED BETWEEN THE TWO WAVE FEATURES. THE SURFACE RIDGE AXIS ALONG THE EAST COAST IS FORECAST TO STRENGTHEN FRIDAY AND SATURDAY WITH DRIER AIR SETTLING SOUTH INTO THE CAROLINAS. THE COOLING TREND EXPECTED TO BEGIN THURSDAY WILL CONTINUE AS LOW LEVEL THICKNESSES ARE PROGGED TO FALL SLIGHTLY EACH DAY....LEADING TO FORECAST HIGHS IN THE LOWER 80S BOTH DAYS. MODELS THEN DIVERGE SLIGHTLY AS THE ECMWF SHOWS THE UPEPR RIDGE WEAKENING MORE RAPIDLY...WITH MCS ACTIVITY TRAVERSING THE OH VALLEY LATE SUNDAY INTO MONDAY. THE GFS HAS A STRONGER UPPER RIDGE WEST OF THE MOUNTAINS...BUT ALLOWS SOME ENERGY ON THE WESTERN PERIPHERY OF THE NORTH ATLANTIC LOW TO DRIFT SOUTHWESTWARD ALONG THE COAST. WITH NO CLEAR SIGNAL AS TO WHICH FEATURE WILL BECOME DOMINANT...AT LEAST THROUGH MONDAY...WE WILL KEEP THE FORECAST DRY WITH A SLIGHT RECOVERY OF TEMPS SUNDAY AND MONDAY. && .AVIATION /12Z TUESDAY THROUGH SATURDAY/... AS OF 738 AM TUESDAY... IFR/LIFR CONDITIONS ARE LIKELY TO PERSIS IN THE TRIAD THROUGH 14Z WHEN A SLOW LIFT TO MVFR IS EXPECTED THROUGH 16Z FOLLOWED BY VFR CONDITIONS AT 18Z. MVFR CIGS AT RDU/RWI/FAY... SIMILARLY... WILL ALSO SLOWLY LIFT TO VFR BY 17-18Z. A MID LEVEL LOW PRESSURE SYSTEM AND SURFACE FRONT LOCATED THROUGH THE MID SOUTH AND GULF STATES THIS MORNING WILL DRIFT SLOWLY EASTWARD THROUGH OUR AREA TODAY AND TONIGHT. A DEEP MOIST FLOW FROM THE SOUTH AND SW IS RESPONSIBLE FOR THE CURRENT ADVERSE AVIATION CONDITIONS... AND THIS FLOW PATTERN WILL PERSIST THROUGH TODAY WITH SLOWLY RISING CIGS THROUGH THE MORNING. HOWEVER... AS CIGS LIFT... WIDESPREAD SHOWERS AND A FEW THUNDERSTORMS ARE EXPECTED TO DEVELOP AREAWIDE... AND A PERIOD OF LOCAL MVFR CIGS -- AND POSSIBLY BRIEFLY IFR -- ARE POSSIBLE IN AND NEAR ANY SHOWERS/STORMS. THE GREATEST COVERAGE OF SHOWERS/STORMS WILL BE 17Z-23Z... WITH RAIN EXITING WEST TO EAST LATE AFTERNOON INTO EARLY EVENING. WITH SKIES STARTING TO CLEAR OUT WEST TO EAST AS A FRONT MOVES THROUGH CENTRAL NC STARTING LATE THIS EVENING... THE DAMP GROUND AND LIGHT WINDS MAY FOSTER MVFR TO IFR GROUND FOG DEVELOPMENT AFTER MIDNIGHT. LOOKING BEYOND 06Z TONIGHT... MVFR TO IFR GROUND FOG IS LIKELY TO DISPERSE PRIOR TO 12Z AT INT/GSO BUT MAY LINGER UNTIL SHORTLY AFTER 12Z AT RDU/RWI/FAY. CIGS ARE EXPECTED TO BE VFR WEDNESDAY AREAWIDE... ALTHOUGH AN ISOLATED LATE DAY STORM IS POSSIBLE MAINLY AT FAY AND LOCAL BRIEF MVFR CONDITIONS MAY OCCUR. OTHERWISE VFR CONDITIONS ARE EXPECTED AT ALL FORECAST SITES THROUGH SATURDAY AS HIGH PRESSURE BUILDS IN FROM THE NORTH. -GIH && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...HARTFIELD NEAR TERM...VINCENT/HARTFIELD SHORT TERM...SMITH LONG TERM...SMITH AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
910 PM CDT WED JUN 13 2012 .DISCUSSION... UPPER LEVEL TROUGH WAS OVER FAR SOUTHERN SASK AND WAS DRIFTING SLOWLY EAST. TROUGH AXIS IS FORECAST TO ROTATE TO A NEGATIVE TILT TONIGHT AND THU AND INCREASE IN FORWARD SPEED ACROSS SOUTHERN CANADA. WATER VAPOR LOOP INDICATED AN UPPER LEVEL JET WAS ON THE SOUTHERN PERIPHERY OF UPPER LOW AND WAS PUNCHING INTO WESTERN ND. THUNDERSTORMS HAVE FORMED ON THE NOSE OF THE JET. MODELS FORECAST LOW LEVEL JET TO INCREASE OVER SD OVERNIGHT AND SHOULD MAINTAIN STORMS THAT FORM OVER EASTERN SD. TRAJECTORY WOULD MOVE STORMS INTO SOUTHEAST ND...WEST CENTRAL AND PARTS OF NORTHWEST MN OVERNIGHT. HAVE INCREASE POPS ARE OVER ND ZONES LATER THIS EVENING AND OVER MUCH OF THE FORECAST AREA OVERNIGHT. SLIGHT RISK AREA FROM SPC HAS SHIFTED NORTH AND EAST. COLD POOL OVER NORTHWEST MN WAS SHIFTING NORTH. HAVE LOWERED TEMPS FOR TONIGHT A COUPLE DEGREES. .PREVIOUS DISCUSSION.../ISSUED 310 PM CDT WED JUN 13 2012/ CONVECTION CHANCES THROUGHOUT THE PERIOD...INCLUDING THE POSSIBILITY OF SEVERE LATE TONIGHT...WILL BE THE PRIMARY FORECAST HEADACHE FOR THE SHORT TERM. WV LOOP SHOWS THE SHORTWAVE TROUGH THAT BROUGHT SHOWERS TO CENTRAL MN DURING THE DAY TODAY HEADING OFF TO THE EAST...WITH THE NEXT SHORTWAVE OVER MT. VIS SAT LOOP HAS SOME FAIRLY VIGOROUS TOWERING CU OVER THE WESTERN CWA...WHICH FITS WITH MODEL SOUNDINGS SHOWING AROUND 800 J/KG AND NOT MUCH CAP. HOWEVER...DEVELOPMENT OF ECHOES ON RADAR HAS NOT REALLY BEEN HAPPENING...AND SPC MESOANALYSIS HAS THE BEST CAPE FURTHER NORTH AND WEST. HRRR HAS SOME BLIPS IN OUR SOUTHWESTERN COUNTIES DURING THE LATE AFTERNOON AND EVENING...BUT QUICKLY DISAPPEARING AND MOST OF THE ACTIVITY COMING IN LATER TONIGHT AS THE MAIN SHORTWAVE COMES EAST. WILL KEEP AN EYE ON SATELLITE/RADAR TRENDS...BUT MAY HAVE TO INCLUDE SOME LOW POPS FOR OUR SOUTHWESTERN COUNTIES IN CASE SOMETHING CAN GET GOING THIS EVENING. ALL MODELS ARE IN FAIRLY GOOD AGREEMENT ON DEVELOPING STORMS OUT IN THE WESTERN DAKOTAS WHERE THE BEST INSTABILITY CURRENTLY IS...AND BRINGING SOMETHING EASTWARD INTO THE CWA BY MORNING. THERE IS A FAIR AMOUNT OF ELEVATED CAPE OVER THE SOUTHWESTERN COUNTIES BY 12Z...AND DEEP LAYER BULK SHEAR INCREASES INTO THE 60 TO 70 KT RANGE. THINK THAT THE PRECIP COULD COME EASTWARD AS A POSSIBLY SEVERE MCS AFTER MIDNIGHT TONIGHT. INCREASED POPS TO 70 PERCENT OVER OUR SOUTHEASTERN COUNTIES...AND PUT IN A SEVERE MENTION. WITH PWATS GETTING UP TO AROUND 1.5 INCHES...HEAVY RAIN COULD BE A POSSIBILITY. THE UPPER TROUGH WILL MOVE OFF INTO SOUTHERN MANITOBA TOMORROW...PUSHING THE SFC TROUGH AXIS EASTWARD THROUGH THE CWA. THUNDERSTORM ACTIVITY SHOULD PUSH EASTWARD AND BE MOSTLY IN MN BY TOMORROW AFTERNOON. WILL CONTINUE TO HAVE TO WATCH FOR SEVERE TOMORROW AFTERNOON AS MODELS CONTINUE TO SHOW A GOOD AMOUNT OF CAPE ABOVE 1500 J/KG AND BULK SHEAR OVER 50 KTS. JUST INCLUDED LIKELY POPS MENTION THOUGH AND LEFT SEVERE MENTION OUT FOR NOW. THURSDAY NIGHT AND FRIDAY SHOULD BE FAIRLY QUIET AS WE SEE SOUTHWESTERLY FLOW ALOFT BETWEEN SYSTEMS. SFC PATTERN WILL BE FAIRLY WEAK...WITH ANOTHER TROUGH NOT COMING IN UNTIL THE NEXT SYSTEM STARTS APPROACHING FRIDAY NIGHT. MODELS SHOW SOME DIFFERENCES IN TIMING ON THE NEXT SHORTWAVE...WITH THE NAM MOST PROGRESSIVE ON BRINGING THE TROUGH OUT INTO THE PLAINS. LEANED TOWARDS THE SLOWER GFS AND ECMWF. CONTINUED TO KEEP POPS IN THE 50-70 PERCENT RANGE FOR LATE FRIDAY NIGHT INTO SATURDAY. TEMPERATURES WILL CONTINUE TO BE FAIRLY WARM...PARTICULARLY FRIDAY AS BOTH THE NAM AND GFS HAVE 850MB TEMPS APPROACHING 20 C IN THE SOUTHERN RED RIVER VALLEY. CONTINUED TO KEEP HIGHS IN THE UPPER 70S TO LOW 80S...WITH SOME SLIGHTLY COOLER TEMPS SATURDAY AFTERNOON. LOWS WILL BE MAINLY IN THE UPPER 50S AND 60S. .LONG TERM... /SAT NIGHT THROUGH WED/ UPPER WAVE/LOW OVER SOUTH CNTRL CANADA WILL RESULT IN A SERIES OF WAVES MOVING ACROSS THE NORTHERN TIER... RESULTING IN A CHANCE OF TSTMS OR SHOWERS THROUGHOUT THE MAJORITY OF THE PERIOD. BEST CHANCE TO NOT SEE ACTIVITY WILL BE SAT NIGHT...AS UPPER WAVE EXITS EASTERN ZONES AND SUBSIDENCE SETS IN. SUN MORNING SHOULD BE DRY AS WELL...BEFORE THE POTENTIAL FOR CONVECTION INCREASES AGAIN BY SUN AFTN. TEMPS WILL GENERALLY BE IN THE 70S AS THE PERIOD WILL BE RATHER CLOUDY. && .AVIATION... HIGH CLOUDS WILL SPREAD ACROSS THE AREA TONIGHT WITH BLOW OFF FROM THUNDERSTORMS TO THE WEST. VFR CONDITIONS WERE ACROSS THE AREA WITH CIGS ABOVE 12 THOUSAND FT. A LOWER CLOUD DECK WAS OVER MUCH OF NORTHWEST MN WAS BETWEEN 35 AND 45 HUNDRED FT AND WAS MOVING NORTHEAST. EXPECT THUNDERSTORMS TO DEVELOP ACROSS SD AND MOVING INTO SOUTHERN ZONES OVERNIGHT. EXPECT VFR CONDITIONS TONIGHT EXCEPT NEAR THUNDERSTORMS. WINDS WILL SHIFT TO THE WEST/SOUTHWEST THU AS COLD FRONT MOVES THROUGH. WINDY AGAIN THU...EXPECT WIND GUSTS TO 30-35 MPH FROM THE WEST && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ HOPPES
AREA FORECAST DISCUSSION
NWS NORMAN OK
1000 PM CDT WED JUN 13 2012 .DISCUSSION... TRIM POPS ACROSS ALL BUT WESTERN NORTH TEXAS AND SOUTHWEST OKLAHOMA. STORMS COMING OFF HIGHER TERRAIN HAVING TROUBLE AND WILL LIKELY DISSIPATE BEFORE MAKING IT INTO BODY OF OKLAHOMA. ACTIVITY OVER FAR SOUTHEAST OKLAHOMA IS EXPECTED TO SLOWLY WEAKEN AND SHIFT SOUTH. MAIN AREA OF STORMS OVERNIGHT AND EARLY FRIDAY MAY BE ASSOCIATED WITH WEAK DISTURBANCE SHIFTING EAST ACROSS SOUTHWEST TEXAS. SCATTERED STORM DEVELOPMENT TRYING TO GET GOING SOUTH AND EAST OF LUBBOCK...AND LATEST RUN OF HRRR DOES KEEP DEVELOPING STORMS FARTHER NORTH AND EAST INTO WESTERN NORTH TEXAS OVERNIGHT. THEREFORE WILL LEAVE CHC POPS GOING THERE. WITH STEEP LAPSE RATES...CANNOT RULE OUT SOME SEVERE HAIL LATE TONIGHT ACROSS WESTERN NORTH TEXAS AND SOUTHWEST OKLAHOMA IF STORMS CAN GET GOING. && .PRELIMINARY POINT TEMPS/POPS... OKLAHOMA CITY OK 67 89 70 92 / 20 20 20 20 HOBART OK 67 90 69 92 / 30 20 20 10 WICHITA FALLS TX 72 92 73 96 / 40 20 20 10 GAGE OK 68 88 70 90 / 20 30 40 20 PONCA CITY OK 69 88 70 92 / 10 20 10 30 DURANT OK 70 89 71 93 / 40 30 30 10 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...NONE. TX...NONE. && $$ 11/09
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1052 AM EDT TUE JUN 12 2012 .SYNOPSIS... A COLD FRONT WILL SWEEP WEST TO EAST ACROSS THE REGION TODAY. A MUCH DRIER AIR MASS WILL BEGIN TO BUILD ACROSS THE SOUTHERN APPALACHIAN REGION TONIGHT. SURFACE HIGH PRESSURE IS EXPECTED TO REMAIN OVER THE WESTERN CAROLINAS AND NORTHEAST GEORGIA INTO EARLY NEXT WEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1045 AM...SHRA ASSOCIATED WITH WEAK SHORT WAVE AND WEAK SFC BOUNDARY WILL MOVE EAST OF THE I-77 CORRIDOR BEFORE NOON. ALTHOUGH WLY FLOW AND DRIER AIR MASS IS TO THE WEST AND COULD MOVE INTO AT LEAST THE WRN CWFA THIS AFTERNOON...LOW LEVEL MOISTURE WILL REMAIN HIGH ACROSS THE AREA. 12Z KGSO RAOB IS INDICATIVE OF THE MOIST AIR MASS WHILE THE KFFC RAOB SHOWS THE DRIER WLY FLOW AIR MASS. THE DRIER AIR MASS SUPPORTS HIGHER INSTABILITY WITH BETTER SFC HEATING AND COOLER MID LEVEL TEMPS. WITH SOME CLEARING OVER THE WEST... EXPECT MORE INSTABILITY THERE AND AN EARLIER CONVECTIVE INITIATION. STORMS SHOULD DEVELOP/MOVE INTO THE ERN CWFA WHERE INSTABILITY DEVELOPS LATER. WITH THE DRIER AIR MASS...DRIER MID LEVELS COULD LEAD TO AN INCREASED CHC OF DOWNBURSTS WHERE STRONGER STORMS FORM. VERY LITTLE SHEAR IS SHOWN ON THE OBSERVED RAOBS OR 12Z UPPER AIR CHARTS...SO NO SIGNIFICANT ORGANIZATION IS EXPECTED. HAVE UPDATED HIGHS WITH THE LATEST BIAS CORRECTED GUIDANCE WHICH SHOWS THE TEMP DISCONTINUITY BETWEEN THE DRIER WEST AND MOISTER EAST QUITE WELL. AS OF 510 AM TUESDAY...ISOLATED SHRA ARE AFFECTING MOST OF THE FA ATTM. AREAS OF DRIZZLE HAVE ALSO STARTED TO DEVELOP PER LOWERING VSBYS ON SOME REGION ASOS AND AWOS STATIONS. DRIZZLE HAS BEEN ADDED TO THE ZONES FOR ALL FOOTHILL AND PIEDMONT LOCATIONS THROUGH 12 UTC AS LOW CLOUDS AND WEAK LLVL ISENTROPIC UPGLIDE WILL CONTINUE THROUGH THIS TIME. POPS HAVE ALSO BEEN RAISED A LITTLE ALONG THE TN LINE. A WEAK MCV WILL APPROACH FROM THE WEST. IT HAS TRIGGERED SHOWERS OVER ERN TN AND THEY SHOULD BEGIN TO AFFECT THE WRN NC MTNS WITHIN THE NEXT 1 TO 2 HOURS. PREVIOUS DISCUSSION... THE LATEST RUN OF THE RAP HAD A CONVECTIVELY INDUCED H5 SHORT WAVE OVER ERN TN. IT DROPS THIS FEATURE SOUTHEASTWARD DURING THE COURSE OF THE MORNING...AND BY EARLY AFTN IT/S LOCATED OVER SOUTH CENTRAL GA. THE GFS MAINTAINS A STRONGER SHORT WAVE OVER THE WRN CAROLINAS... WHILE THE NAM IS NOT A STRONG WITH THE WAVE. OVERALL...THE GFS MAY BE OVERDONE WITH THIS FEATURE. THE GFS BUFKIT SOUNDINGS LOOK MODESTLY IMPRESSIVE THIS AFTN WITH CAPE VALUES RANGING FROM 1200-1500 J/KG AND LITTLE IF ANY INHIBITION. THE NAM STILL HAS PLENTY OF INSTABILITY...BUT IT MAINTAINS MORE CAPPING IN THE LOW LEVELS. I STILL PLAN TO CARRY LOW END LIKELY POPS ACROSS MOST OF THE FA...AND IN PARTICULAR THE I-77 CORRIDOR...BUT THE RECENT SOUTHWARD SHIFT OF THE SHORT WAVE DOES NOT BODE AS WELL FOR EXTENSIVE CONVECTIVE COVERAGE. WITH MORE DRYING ALOFT...THERE IS A CHANCE FOR A FEW DAMAGING DOWNBURSTS TODAY. IN FACT...THE NAM SFC DELTA THETA-E VALUES ARE IN THE MID 20S WHICH WOULD CERTAINLY SUPPORT DAMAGING WINDS WITH THE STRONGER STORMS THIS AFTERNOON. A COLD FRONT WILL CROSS THE REGION OVERNIGHT. I HAVE CONVECTION ENDING FAIRLY QUICKLY THIS EVENING AS THE SOUNDINGS SHOW CONSIDERABLE LOW LEVEL INHIBITION EVEN WITH THE BNDRY PUSHING ACROSS THE REGION. && .SHORT TERM /WEDNESDAY THROUGH FRIDAY/... AS OF 220 AM TUESDAY...BY DAYBREAK WEDNESDAY....THE COLD FRONT WILL SLIDE EAST OFF THE CAROLINA COAST AS HIGH PRESSURE BUILDS ACROSS THE GREAT LAKES AREA. A BLEND OF THE GFS AND ECMWF INDICATES THAT THE CWA WILL REMAIN ON THE SOUTHERN EDGE OF SFC HIGH PRESSURE WEDNESDAY AND THURSDAY. IN THE MID LEVELS...THE EARLY PHASE OF AN OMEGA BLOCK WILL DEVELOP ACROSS THE CONUS...WITH RIDGING BUILDING NORTH ACROSS THE MISSISSIPPI AND OHIO RIVER VALLEYS. BOTH SOLUTIONS INDICATE THAT A SHALLOW POOL OF MOISTURE AND WEAK INSTABILITY WILL REMAIN ACROSS THE NC MTNS WEDNESDAY AND THURSDAY. I WILL CONTINUE TO INDICATE DIURNAL SCHC POPS ACROSS THE MTNS...ISO ACROSS THE FOOTHILLS AND PIEDMONT. HIGH TEMPERATURES MAY RANGE FROM L80S ACROSS THE MTN VALLEYS TO THE U80S TO AROUND 90 DEGREES EAST OF I-85 ON WEDNESDAY. HIGH TEMPERATURES ON THURSDAY MAY REMAIN AROUND 1 TO 2 DEGREES COOLER THAN WEDNESDAY. LOWS WEDNESDAY NIGHT ARE FORECAST TO RANGE FROM U50S ACROSS THE MTNS TO MID 60S EAST. && .LONG TERM /FRIDAY NIGHT THROUGH MONDAY/... AS OF 230 AM TUESDAY...FRIDAY THROUGH MONDAY...THE MID LEVEL PATTERN WILL REMAIN SOLIDLY BLOCK THROUGH MOST OF THE PERIOD...BEGINNING TO WEAKEN EARLY NEXT WEEK. THE MAIN MID LEVEL FEATURES WILL REMAIN THE RIDGE CENTER ACROSS THE MID WEST WITH LOW PRESSURE OVER THE WESTERN ATLANTIC. AT THE SFC...HIGH PRESSURE WILL REMAIN CENTERED OVER NEW ENGLAND WITH RIDGING EXTENDING SW ACROSS THE CWA. GFS FORECAST SOUNDINGS INDICATES THAT WEAK INSTABILITY AND WEAK LLVL CIN WILL EXIST ACROSS THE MTNS EACH AFTERNOON AND EVENING. I WILL MAINTAIN DIURNAL SCHC ACROSS THE MTNS FOR SHRA AND TSRA. TEMPERATURES EACH DAY SHOULD CHANGE VERY LITTLE FROM DAY TO DAY...RANGING FROM U70S ACROSS THE MTN VALLEYS TO MID 80S EAST. LOW TEMPERATURES ARE FORECAST TO RANGE FROM U50S ACROSS THE MTN VALLEYS TO L60S EAST. && .AVIATION /15Z TUESDAY THROUGH SATURDAY/... AT KCLT...MOIST SOUTHWEST FLOW SHOULD KEEP CIGS IN THE 200 TO 400 FOOT RANGE UP UNTIL AROUND 14 UTC. THEREAFTER THE CIGS SHOULD LIFT FAIRLY QUICKLY. AREAS OF DRIZZLE AND FOG AND A FEW HEAVIER SHRA WILL ALSO LAST THROUGH 14 UTC. BY EARLY AFTN SCT TO NUMEROUS SHRA/TSTMS WILL DEVELOP AROUND THE AIRFIELD AS AN UPPER LOW CROSSES THE REGION. THE STORMS SHOULD END AROUND 00 UTC. A COLD FRONT WILL CROSS THE AIRFIELD ABOUT THAT TIME...TURNING WINDS LIGHT OUT OF THE NORTHWEST. THE WINDS WILL BECOME A LITTLE STRONGER AND TURN OUT OF THE NE TOWARD MORNING. KAVL AND KHKY...DOWNSLOPE FLOW HAS MADE IT HARDER FOR LOW CIGS TO FORM AT KAVL AND KHKY. AFTER 12 UTC CONDITIONS ARE GENERALLY EXPECTED TO BE VFR...THOUGH PATCHES OF IFR STRATUS WILL STILL BE IN THE VICINITY UNTIL AROUND 13 UTC. AN UPPER LOW WILL CROSS THE REGION LATE THIS MORNING AND INTO THE AFTN. THIS WILL TRIGGER SCT TO NUMEROUS SHRA AND TSTMS IN THE VCNTY OF BOTH AIRFIELDS. THE WINDS SHOULD TURN OUT OF THE NW AT KHKY BY LATE AFTN AND THE WINDS WILL BE NW THROUGH THE DAY AT KAVL. DRIER AIR TONIGHT SHOULD LIMIT ANY RESTRICTIONS TO A BRIEF PERIOD OF MVFR FOG. ELSEWHERE...200 TO 400 FOOT CIGS SHOULD LIFT INTO THE THE MVFR RANGE BY 14 UTC AS THE WINDS TURN MORE DOWNSLOPE AT KGMU AND KGSP. AREAS OF DRIZZLE AND FOG WILL END BY THAT TIME AS WELL. CONDITIONS WILL BE BETTER AT KAND. SCT TSTMS WILL DEVELOP IN THE VCNTY OF THE AIRFIELDS THIS AFTN AS AN UPPER LOW CROSSES THE REGION. THE CONVECTION SHOULD END BY 00 UTC. A COLD FRONT WILL CROSS THE REGION OVERNIGHT. THE WINDS WILL GRADUALLY TURN OUT OF THE WEST AND THEN NORTHWEST OVERNIGHT. THE WINDS WILL INCREASE A LITTLE OUT OF THE NE BY SUNRISE WED. OUTLOOK...GENERALLY DRY CONDITIONS ARE NOW EXPECTED BEHIND A COLD FRONT WEDNESDAY THROUGH SATURDAY. HOWEVER...ISOLATED AFTERNOON TSTMS WILL DEVELOP OVER THE MTNS EACH DAY...WHICH COULD HAVE SOME AFFECT ON OPERATIONS AT KAVL. AN EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLE SHOWING THE PERCENTAGE OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED ISSUANCE CATEGORY IS AVAILABLE AT FOLLOWING LINK (USE LOWER CASE)... WWW.WEATHER.GOV/GSP/AVIATION/TABLES.HTM && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...NED NEAR TERM...MCAVOY/RWH SHORT TERM...NED LONG TERM...NED AVIATION...MCAVOY
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
733 AM EDT TUE JUN 12 2012 .SYNOPSIS... A COLD FRONT WILL SWEEP WEST TO EAST ACROSS THE REGION TODAY. A MUCH DRIER AIR MASS WILL BEGIN TO BUILD ACROSS THE SOUTHERN APPALACHIAN REGION TONIGHT. SURFACE HIGH PRESSURE IS EXPECTED TO REMAIN OVER THE WESTERN CAROLINAS AND NORTHEAST GEORGIA INTO EARLY NEXT WEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 510 AM TUESDAY...ISOLATED SHRA ARE AFFECTING MOST OF THE FA ATTM. AREAS OF DRIZZLE HAVE ALSO STARTED TO DEVELOP PER LOWERING VSBYS ON SOME REGION ASOS AND AWOS STATIONS. DRIZZLE HAS BEEN ADDED TO THE ZONES FOR ALL FOOTHILL AND PIEDMONT LOCATIONS THROUGH 12 UTC AS LOW CLOUDS AND WEAK LLVL ISENTROPIC UPGLIDE WILL CONTINUE THROUGH THIS TIME. POPS HAVE ALSO BEEN RAISED A LITTLE ALONG THE TN LINE. A WEAK MCV WILL APPROACH FROM THE WEST. IT HAS TRIGGERED SHOWERS OVER ERN TN AND THEY SHOULD BEGIN TO AFFECT THE WRN NC MTNS WITHIN THE NEXT 1 TO 2 HOURS. PREVIOUS DISCUSSION... THE LATEST RUN OF THE RAP HAD A CONVECTIVELY INDUCED H5 SHORT WAVE OVER ERN TN. IT DROPS THIS FEATURE SOUTHEASTWARD DURING THE COURSE OF THE MORNING...AND BY EARLY AFTN IT/S LOCATED OVER SOUTH CENTRAL GA. THE GFS MAINTAINS A STRONGER SHORT WAVE OVER THE WRN CAROLINAS... WHILE THE NAM IS NOT A STRONG WITH THE WAVE. OVERALL...THE GFS MAY BE OVERDONE WITH THIS FEATURE. THE GFS BUFKIT SOUNDINGS LOOK MODESTLY IMPRESSIVE THIS AFTN WITH CAPE VALUES RANGING FROM 1200-1500 J/KG AND LITTLE IF ANY INHIBITION. THE NAM STILL HAS PLENTY OF INSTABILITY...BUT IT MAINTAINS MORE CAPPING IN THE LOW LEVELS. I STILL PLAN TO CARRY LOW END LIKELY POPS ACROSS MOST OF THE FA...AND IN PARTICULAR THE I-77 CORRIDOR...BUT THE RECENT SOUTHWARD SHIFT OF THE SHORT WAVE DOES NOT BODE AS WELL FOR EXTENSIVE CONVECTIVE COVERAGE. WITH MORE DRYING ALOFT...THERE IS A CHANCE FOR A FEW DAMAGING DOWNBURSTS TODAY. IN FACT...THE NAM SFC DELTA THETA-E VALUES ARE IN THE MID 20S WHICH WOULD CERTAINLY SUPPORT DAMAGING WINDS WITH THE STRONGER STORMS THIS AFTERNOON. A COLD FRONT WILL CROSS THE REGION OVERNIGHT. I HAVE CONVECTION ENDING FAIRLY QUICKLY THIS EVENING AS THE SOUNDINGS SHOW CONSIDERABLE LOW LEVEL INHIBITION EVEN WITH THE BNDRY PUSHING ACROSS THE REGION. && .SHORT TERM /WEDNESDAY THROUGH FRIDAY/... AS OF 220 AM TUESDAY...BY DAYBREAK WEDNESDAY....THE COLD FRONT WILL SLIDE EAST OFF THE CAROLINA COAST AS HIGH PRESSURE BUILDS ACROSS THE GREAT LAKES AREA. A BLEND OF THE GFS AND ECMWF INDICATES THAT THE CWA WILL REMAIN ON THE SOUTHERN EDGE OF SFC HIGH PRESSURE WEDNESDAY AND THURSDAY. IN THE MID LEVELS...THE EARLY PHASE OF AN OMEGA BLOCK WILL DEVELOP ACROSS THE CONUS...WITH RIDGING BUILDING NORTH ACROSS THE MISSISSIPPI AND OHIO RIVER VALLEYS. BOTH SOLUTIONS INDICATE THAT A SHALLOW POOL OF MOISTURE AND WEAK INSTABILITY WILL REMAIN ACROSS THE NC MTNS WEDNESDAY AND THURSDAY. I WILL CONTINUE TO INDICATE DIURNAL SCHC POPS ACROSS THE MTNS...ISO ACROSS THE FOOTHILLS AND PIEDMONT. HIGH TEMPERATURES MAY RANGE FROM L80S ACROSS THE MTN VALLEYS TO THE U80S TO AROUND 90 DEGREES EAST OF I-85 ON WEDNESDAY. HIGH TEMPERATURES ON THURSDAY MAY REMAIN AROUND 1 TO 2 DEGREES COOLER THAN WEDNESDAY. LOWS WEDNESDAY NIGHT ARE FORECAST TO RANGE FROM U50S ACROSS THE MTNS TO MID 60S EAST. && .LONG TERM /FRIDAY NIGHT THROUGH MONDAY/... AS OF 230 AM TUESDAY...FRIDAY THROUGH MONDAY...THE MID LEVEL PATTERN WILL REMAIN SOLIDLY BLOCK THROUGH MOST OF THE PERIOD...BEGINNING TO WEAKEN EARLY NEXT WEEK. THE MAIN MID LEVEL FEATURES WILL REMAIN THE RIDGE CENTER ACROSS THE MID WEST WITH LOW PRESSURE OVER THE WESTERN ATLANTIC. AT THE SFC...HIGH PRESSURE WILL REMAIN CENTERED OVER NEW ENGLAND WITH RIDGING EXTENDING SW ACROSS THE CWA. GFS FORECAST SOUNDINGS INDICATES THAT WEAK INSTABILITY AND WEAK LLVL CIN WILL EXIST ACROSS THE MTNS EACH AFTERNOON AND EVENING. I WILL MAINTAIN DIURNAL SCHC ACROSS THE MTNS FOR SHRA AND TSRA. TEMPERATURES EACH DAY SHOULD CHANGE VERY LITTLE FROM DAY TO DAY...RANGING FROM U70S ACROSS THE MTN VALLEYS TO MID 80S EAST. LOW TEMPERATURES ARE FORECAST TO RANGE FROM U50S ACROSS THE MTN VALLEYS TO L60S EAST. && .AVIATION /12Z TUESDAY THROUGH SATURDAY/... AT KCLT...MOIST SOUTHWEST FLOW SHOULD KEEP CIGS IN THE 200 TO 400 FOOT RANGE UP UNTIL AROUND 14 UTC. THEREAFTER THE CIGS SHOULD LIFT FAIRLY QUICKLY. AREAS OF DRIZZLE AND FOG AND A FEW HEAVIER SHRA WILL ALSO LAST THROUGH 14 UTC. BY EARLY AFTN SCT TO NUMEROUS SHRA/TSTMS WILL DEVELOP AROUND THE AIRFIELD AS AN UPPER LOW CROSSES THE REGION. THE STORMS SHOULD END AROUND 00 UTC. A COLD FRONT WILL CROSS THE AIRFIELD ABOUT THAT TIME...TURNING WINDS LIGHT OUT OF THE NORTHWEST. THE WINDS WILL BECOME A LITTLE STRONGER AND TURN OUT OF THE NE TOWARD MORNING. KAVL AND KHKY...DOWNSLOPE FLOW HAS MADE IT HARDER FOR LOW CIGS TO FORM AT KAVL AND KHKY. AFTER 12 UTC CONDITIONS ARE GENERALLY EXPECTED TO BE VFR...THOUGH PATCHES OF IFR STRATUS WILL STILL BE IN THE VICINITY UNTIL AROUND 13 UTC. AN UPPER LOW WILL CROSS THE REGION LATE THIS MORNING AND INTO THE AFTN. THIS WILL TRIGGER SCT TO NUMEROUS SHRA AND TSTMS IN THE VCNTY OF BOTH AIRFIELDS. THE WINDS SHOULD TURN OUT OF THE NW AT KHKY BY LATE AFTN AND THE WINDS WILL BE NW THROUGH THE DAY AT KAVL. DRIER AIR TONIGHT SHOULD LIMIT ANY RESTRICTIONS TO A BRIEF PERIOD OF MVFR FOG. ELSEWHERE...200 TO 400 FOOT CIGS SHOULD LIFT INTO THE THE MVFR RANGE BY 14 UTC AS THE WINDS TURN MORE DOWNSLOPE AT KGMU AND KGSP. AREAS OF DRIZZLE AND FOG WILL END BY THAT TIME AS WELL. CONDITIONS WILL BE BETTER AT KAND. SCT TSTMS WILL DEVELOP IN THE VCNTY OF THE AIRFIELDS THIS AFTN AS AN UPPER LOW CROSSES THE REGION. THE CONVECTION SHOULD END BY 00 UTC. A COLD FRONT WILL CROSS THE REGION OVERNIGHT. THE WINDS WILL GRADUALLY TURN OUT OF THE WEST AND THEN NORTHWEST OVERNIGHT. THE WINDS WILL INCREASE A LITTLE OUT OF THE NE BY SUNRISE WED. OUTLOOK...GENERALLY DRY CONDITIONS ARE NOW EXPECTED BEHIND A COLD FRONT WEDNESDAY THROUGH SATURDAY. HOWEVER...ISOLATED AFTERNOON TSTMS WILL DEVELOP OVER THE MTNS EACH DAY...WHICH COULD HAVE SOME AFFECT ON OPERATIONS AT KAVL. AN EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLE SHOWING THE PERCENTAGE OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED ISSUANCE CATEGORY IS AVAILABLE AT FOLLOWING LINK (USE LOWER CASE)... WWW.WEATHER.GOV/GSP/AVIATION/TABLES.HTM && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...NED NEAR TERM...MCAVOY SHORT TERM...NED LONG TERM...NED AVIATION...MCAVOY
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
510 AM EDT TUE JUN 12 2012 .SYNOPSIS... A COLD FRONT WILL SWEEP WEST TO EAST ACROSS THE REGION TODAY. A MUCH DRIER AIR MASS WILL BEGIN TO BUILD ACROSS THE SOUTHERN APPALACHIAN REGION TONIGHT. SURFACE HIGH PRESSURE IS EXPECTED TO REMAIN OVER THE WESTERN CAROLINAS AND NORTHEAST GEORGIA INTO EARLY NEXT WEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 510 AM TUESDAY...ISOLATED SHRA ARE AFFECTING MOST OF THE FA ATTM. AREAS OF DRIZZLE HAVE ALSO STARTED TO DEVELOP PER LOWERING VSBYS ON SOME REGION ASOS AND AWOS STATIONS. DRIZZLE HAS BEEN ADDED TO THE ZONES FOR ALL FOOTHILL AND PIEDMONT LOCATIONS THROUGH 12 UTC AS LOW CLOUDS AND WEAK LLVL ISENTROPIC UPGLIDE WILL CONTINUE THROUGH THIS TIME. POPS HAVE ALSO BEEN RAISED A LITTLE ALONG THE TN LINE. A WEAK MCV WILL APPROACH FROM THE WEST. IT HAS TRIGGERED SHOWERS OVER ERN TN AND THEY SHOULD BEGIN TO AFFECT THE WRN NC MTNS WITHIN THE NEXT 1 TO 2 HOURS. PREVIOUS DISCUSSION... THE LATEST RUN OF THE RAP HAD A CONVECTIVELY INDUCED H5 SHORT WAVE OVER ERN TN. IT DROPS THIS FEATURE SOUTHEASTWARD DURING THE COURSE OF THE MORNING...AND BY EARLY AFTN IT/S LOCATED OVER SOUTH CENTRAL GA. THE GFS MAINTAINS A STRONGER SHORT WAVE OVER THE WRN CAROLINAS... WHILE THE NAM IS NOT A STRONG WITH THE WAVE. OVERALL...THE GFS MAY BE OVERDONE WITH THIS FEATURE. THE GFS BUFKIT SOUNDINGS LOOK MODESTLY IMPRESSIVE THIS AFTN WITH CAPE VALUES RANGING FROM 1200-1500 J/KG AND LITTLE IF ANY INHIBITION. THE NAM STILL HAS PLENTY OF INSTABILITY...BUT IT MAINTAINS MORE CAPPING IN THE LOW LEVELS. I STILL PLAN TO CARRY LOW END LIKELY POPS ACROSS MOST OF THE FA...AND IN PARTICULAR THE I-77 CORRIDOR...BUT THE RECENT SOUTHWARD SHIFT OF THE SHORT WAVE DOES NOT BODE AS WELL FOR EXTENSIVE CONVECTIVE COVERAGE. WITH MORE DRYING ALOFT...THERE IS A CHANCE FOR A FEW DAMAGING DOWNBURSTS TODAY. IN FACT...THE NAM SFC DELTA THETA-E VALUES ARE IN THE MID 20S WHICH WOULD CERTAINLY SUPPORT DAMAGING WINDS WITH THE STRONGER STORMS THIS AFTERNOON. A COLD FRONT WILL CROSS THE REGION OVERNIGHT. I HAVE CONVECTION ENDING FAIRLY QUICKLY THIS EVENING AS THE SOUNDINGS SHOW CONSIDERABLE LOW LEVEL INHIBITION EVEN WITH THE BNDRY PUSHING ACROSS THE REGION. && .SHORT TERM /WEDNESDAY THROUGH FRIDAY/... AS OF 220 AM TUESDAY...BY DAYBREAK WEDNESDAY....THE COLD FRONT WILL SLIDE EAST OFF THE CAROLINA COAST AS HIGH PRESSURE BUILDS ACROSS THE GREAT LAKES AREA. A BLEND OF THE GFS AND ECMWF INDICATES THAT THE CWA WILL REMAIN ON THE SOUTHERN EDGE OF SFC HIGH PRESSURE WEDNESDAY AND THURSDAY. IN THE MID LEVELS...THE EARLY PHASE OF AN OMEGA BLOCK WILL DEVELOP ACROSS THE CONUS...WITH RIDGING BUILDING NORTH ACROSS THE MISSISSIPPI AND OHIO RIVER VALLEYS. BOTH SOLUTIONS INDICATE THAT A SHALLOW POOL OF MOISTURE AND WEAK INSTABILITY WILL REMAIN ACROSS THE NC MTNS WEDNESDAY AND THURSDAY. I WILL CONTINUE TO INDICATE DIURNAL SCHC POPS ACROSS THE MTNS...ISO ACROSS THE FOOTHILLS AND PIEDMONT. HIGH TEMPERATURES MAY RANGE FROM L80S ACROSS THE MTN VALLEYS TO THE U80S TO AROUND 90 DEGREES EAST OF I-85 ON WEDNESDAY. HIGH TEMPERATURES ON THURSDAY MAY REMAIN AROUND 1 TO 2 DEGREES COOLER THAN WEDNESDAY. LOWS WEDNESDAY NIGHT ARE FORECAST TO RANGE FROM U50S ACROSS THE MTNS TO MID 60S EAST. && .LONG TERM /FRIDAY NIGHT THROUGH MONDAY/... AS OF 230 AM TUESDAY...FRIDAY THROUGH MONDAY...THE MID LEVEL PATTERN WILL REMAIN SOLIDLY BLOCK THROUGH MOST OF THE PERIOD...BEGINNING TO WEAKEN EARLY NEXT WEEK. THE MAIN MID LEVEL FEATURES WILL REMAIN THE RIDGE CENTER ACROSS THE MID WEST WITH LOW PRESSURE OVER THE WESTERN ATLANTIC. AT THE SFC...HIGH PRESSURE WILL REMAIN CENTERED OVER NEW ENGLAND WITH RIDGING EXTENDING SW ACROSS THE CWA. GFS FORECAST SOUNDINGS INDICATES THAT WEAK INSTABILITY AND WEAK LLVL CIN WILL EXIST ACROSS THE MTNS EACH AFTERNOON AND EVENING. I WILL MAINTAIN DIURNAL SCHC ACROSS THE MTNS FOR SHRA AND TSRA. TEMPERATURES EACH DAY SHOULD CHANGE VERY LITTLE FROM DAY TO DAY...RANGING FROM U70S ACROSS THE MTN VALLEYS TO MID 80S EAST. LOW TEMPERATURES ARE FORECAST TO RANGE FROM U50S ACROSS THE MTN VALLEYS TO L60S EAST. && .AVIATION /09Z TUESDAY THROUGH SATURDAY/... AT KCLT...A VERY MOIST AIRMASS AND INCREASING SOUTHWEST WINDS IN THE BNDRY LAYER HAVE RESULTED IN WIDESPREAD IFR TO LIFR CIGS ACROSS THE REGION. CIGS SHOULD HOLD BETWEEN 400 AND 600 FEET THROUGH MID MORNING BEFORE MIXING INTO A VFR CU FIELD IN THE AFTN. SCT SHRA ARE DEVELOPING WEST OF THE AIRFIELD. WITH LIMITED INSTABILITY I DIDN/T THINK THE SHRA WOULD MAKE IT TO KCLT...BUT IF THE INCREASING TREND CONTINUES...SOME SHRA WILL BE ADDED TO THE TAF. AN UPPER LOW WILL CROSS THE REGION THIS AFTN...KICKING OFF NUMEROUS SHRA/TSTMS ONCE AGAIN...LASTING INTO THE EARLY EVENING HOURS. PROB30 HAS BEEN INCLUDED TO ACCOUNT FOR THIS. ELSEWHERE...LIKE AT KCLT...SOUTHWEST WINDS AND A VERY MOIST AIRMASS HAS RESULTED IN WIDESPREAD STRATUS CIGS WHICH HAVE GENERALLY SETTLED INTO THE 400 TO 600 FOOT RANGE. THESE GENERAL CONDITIONS SHOULD CONTINUE THROUGH MID MORNING. HOWEVER...AREAS OF FOG AND POSSIBLY EVEN LOWER CIGS ARE EXPECTED TO DEVELOP AT KAVL AND KHKY WHERE THE WINDS WILL BE LIGHTER. LIGHT SHRA CONTINUE TO DEVELOP IN THE MOIST AIRMASS NEAR THE MTNS...AND LIGHT RAIN HAS BEEN CARRIED AT KGSP...KGMU AND KHKY MOST OF THE NIGHT WHERE THE LIGHT RAIN AND DRIZZLE SHOULD CONTINUE FOR SEVERAL MORE HOURS. CIGS WILL MIX INTO A VFR CU FIELD IN THE AFTN. NUMEROUS SHRA/TSTMS WILL DEVELOP AGAIN AS AN UPPER LOW CROSSES THE REGION. THE MOST LIKELY PERIOD FOR TSTMS IS IN THE EARLY TO MID AFTN HOURS. OUTLOOK...GENERALLY DRY CONDITIONS ARE NOW EXPECTED BEHIND A COLD FRONT WEDNESDAY THROUGH FRIDAY. HOWEVER...ISOLATED AFTERNOON TSTMS WILL DEVELOP OVER THE MTNS EACH DAY...WHICH COULD HAVE SOME AFFECT ON OPERATIONS AT KAVL. AN EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLE SHOWING THE PERCENTAGE OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED ISSUANCE CATEGORY IS AVAILABLE AT FOLLOWING LINK (USE LOWER CASE)... WWW.WEATHER.GOV/GSP/AVIATION/TABLES.HTM && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...NED NEAR TERM...MCAVOY SHORT TERM...NED LONG TERM...NED AVIATION...MCAVOY
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
325 AM EDT TUE JUN 12 2012 .SYNOPSIS... A COLD FRONT WILL SWEEP WEST TO EAST ACROSS THE REGION TODAY. A MUCH DRIER AIR MASS WILL BEGIN TO BUILD ACROSS THE SOUTHERN APPALACHIAN REGION TONIGHT. SURFACE HIGH PRESSURE IS EXPECTED TO REMAIN OVER THE WESTERN CAROLINAS AND NORTHEAST GEORGIA INTO EARLY NEXT WEEK. && .NEAR TERM /THROUGH TONIGHT/... THE LATEST RUN OF THE RAP HAD A CONVECTIVELY INDUCED H5 SHORT WAVE OVER ERN TN. IT DROPS THIS FEATURE SOUTHEASTWARD DURING THE COURSE OF THE MORNING...AND BY EARLY AFTN IT/S LOCATED OVER SOUTH CENTRAL GA. THE GFS MAINTAINS A STRONGER SHORT WAVE OVER THE WRN CAROLINAS... WHILE THE NAM IS NOT A STRONG WITH THE WAVE. OVERALL...THE GFS MAY BE OVERDONE WITH THIS FEATURE. THE GFS BUFKIT SOUNDINGS LOOK MODESTLY IMPRESSIVE THIS AFTN WITH CAPE VALUES RANGING FROM 1200-1500 J/KG AND LITTLE IF ANY INHIBITION. THE NAM STILL HAS PLENTY OF INSTABILITY...BUT IT MAINTAINS MORE CAPPING IN THE LOW LEVELS. I STILL PLAN TO CARRY LOW END LIKELY POPS ACROSS MOST OF THE FA...AND IN PARTICULAR THE I-77 CORRIDOR...BUT THE RECENT SOUTHWARD SHIFT OF THE SHORT WAVE DOES NOT BODE AS WELL FOR EXTENSIVE CONVECTIVE COVERAGE. WITH MORE DRYING ALOFT...THERE IS A CHANCE FOR A FEW DAMAGING DOWNBURSTS TODAY. IN FACT...THE NAM SFC DELTA THETA-E VALUES ARE IN THE MID 20S WHICH WOULD CERTAINLY SUPPORT DAMAGING WINDS WITH THE STRONGER STORMS THIS AFTERNOON. A COLD FRONT WILL CROSS THE REGION OVERNIGHT. I HAVE CONVECTION ENDING FAIRLY QUICKLY THIS EVENING AS THE SOUNDINGS SHOW CONSIDERABLE LOW LEVEL INHIBITION EVEN WITH THE BNDRY PUSHING ACROSS THE REGION. && .SHORT TERM /WEDNESDAY THROUGH FRIDAY/... AS OF 220 AM TUESDAY...BY DAYBREAK WEDNESDAY....THE COLD FRONT WILL SLIDE EAST OFF THE CAROLINA COAST AS HIGH PRESSURE BUILDS ACROSS THE GREAT LAKES AREA. A BLEND OF THE GFS AND ECMWF INDICATES THAT THE CWA WILL REMAIN ON THE SOUTHERN EDGE OF SFC HIGH PRESSURE WEDNESDAY AND THURSDAY. IN THE MID LEVELS...THE EARLY PHASE OF AN OMEGA BLOCK WILL DEVELOP ACROSS THE CONUS...WITH RIDGING BUILDING NORTH ACROSS THE MISSISSIPPI AND OHIO RIVER VALLEYS. BOTH SOLUTIONS INDICATE THAT A SHALLOW POOL OF MOISTURE AND WEAK INSTABILITY WILL REMAIN ACROSS THE NC MTNS WEDNESDAY AND THURSDAY. I WILL CONTINUE TO INDICATE DIURNAL SCHC POPS ACROSS THE MTNS...ISO ACROSS THE FOOTHILLS AND PIEDMONT. HIGH TEMPERATURES MAY RANGE FROM L80S ACROSS THE MTN VALLEYS TO THE U80S TO AROUND 90 DEGREES EAST OF I-85 ON WEDNESDAY. HIGH TEMPERATURES ON THURSDAY MAY REMAIN AROUND 1 TO 2 DEGREES COOLER THAN WEDNESDAY. LOWS WEDNESDAY NIGHT ARE FORECAST TO RANGE FROM U50S ACROSS THE MTNS TO MID 60S EAST. && .LONG TERM /FRIDAY NIGHT THROUGH MONDAY/... AS OF 230 AM TUESDAY...FRIDAY THROUGH MONDAY...THE MID LEVEL PATTERN WILL REMAIN SOLIDLY BLOCK THROUGH MOST OF THE PERIOD...BEGINNING TO WEAKEN EARLY NEXT WEEK. THE MAIN MID LEVEL FEATURES WILL REMAIN THE RIDGE CENTER ACROSS THE MID WEST WITH LOW PRESSURE OVER THE WESTERN ATLANTIC. AT THE SFC...HIGH PRESSURE WILL REMAIN CENTERED OVER NEW ENGLAND WITH RIDGING EXTENDING SW ACROSS THE CWA. GFS FORECAST SOUNDINGS INDICATES THAT WEAK INSTABILITY AND WEAK LLVL CIN WILL EXIST ACROSS THE MTNS EACH AFTERNOON AND EVENING. I WILL MAINTAIN DIURNAL SCHC ACROSS THE MTNS FOR SHRA AND TSRA. TEMPERATURES EACH DAY SHOULD CHANGE VERY LITTLE FROM DAY TO DAY...RANGING FROM U70S ACROSS THE MTN VALLEYS TO MID 80S EAST. LOW TEMPERATURES ARE FORECAST TO RANGE FROM U50S ACROSS THE MTN VALLEYS TO L60S EAST. && .AVIATION /08Z TUESDAY THROUGH SATURDAY/... AT KCLT...A VERY MOIST AIRMASS AND INCREASING SOUTHWEST WINDS IN THE BNDRY LAYER HAVE RESULTED IN WIDESPREAD IFR TO LIFR CIGS ACROSS THE REGION. CIGS SHOULD HOLD BETWEEN 400 AND 600 FEET THROUGH MID MORNING BEFORE MIXING INTO A VFR CU FIELD IN THE AFTN. SCT SHRA ARE DEVELOPING WEST OF THE AIRFIELD. WITH LIMITED INSTABILITY I DIDN/T THINK THE SHRA WOULD MAKE IT TO KCLT...BUT IF THE INCREASING TREND CONTINUES...SOME SHRA WILL BE ADDED TO THE TAF. AN UPPER LOW WILL CROSS THE REGION THIS AFTN...KICKING OFF NUMEROUS SHRA/TSTMS ONCE AGAIN...LASTING INTO THE EARLY EVENING HOURS. PROB30 HAS BEEN INCLUDED TO ACCOUNT FOR THIS. ELSEWHERE...LIKE AT KCLT...SOUTHWEST WINDS AND A VERY MOIST AIRMASS HAS RESULTED IN WIDESPREAD STRATUS CIGS WHICH HAVE GENERALLY SETTLED INTO THE 400 TO 600 FOOT RANGE. THESE GENERAL CONDITIONS SHOULD CONTINUE THROUGH MID MORNING. HOWEVER...AREAS OF FOG AND POSSIBLY EVEN LOWER CIGS ARE EXPECTED TO DEVELOP AT KAVL AND KHKY WHERE THE WINDS WILL BE LIGHTER. LIGHT SHRA CONTINUE TO DEVELOP IN THE MOIST AIRMASS NEAR THE MTNS...AND LIGHT RAIN HAS BEEN CARRIED AT KGSP...KGMU AND KHKY MOST OF THE NIGHT WHERE THE LIGHT RAIN AND DRIZZLE SHOULD CONTINUE FOR SEVERAL MORE HOURS. CIGS WILL MIX INTO A VFR CU FIELD IN THE AFTN. NUMEROUS SHRA/TSTMS WILL DEVELOP AGAIN AS AN UPPER LOW CROSSES THE REGION. THE MOST LIKELY PERIOD FOR TSTMS IS IN THE EARLY TO MID AFTN HOURS. OUTLOOK...GENERALLY DRY CONDITIONS ARE NOW EXPECTED BEHIND A COLD FRONT WEDNESDAY THROUGH FRIDAY. HOWEVER...ISOLATED AFTERNOON TSTMS WILL DEVELOP OVER THE MTNS EACH DAY...WHICH COULD HAVE SOME AFFECT ON OPERATIONS AT KAVL. AN EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLE SHOWING THE PERCENTAGE OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED ISSUANCE CATEGORY IS AVAILABLE AT FOLLOWING LINK (USE LOWER CASE)... WWW.WEATHER.GOV/GSP/AVIATION/TABLES.HTM && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...NED NEAR TERM...MCAVOY SHORT TERM...NED LONG TERM...NED AVIATION...MCAVOY
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
920 PM CDT WED JUN 13 2012 .UPDATE... RUC/NAM SEEM TO HAVE A HANDLE ON SEVERE STORMS AROUND THE REGION THIS EVENING. RUC HANDLED EARLIER STORMS TO THE SOUTH AND SOUTHEAST WELL. NAM TIMED THE ONES WEST OF THE MO ALMOST PERFECTLY. ANTICIPATING FIRST WARNING WITHIN THE NEXT HOUR FOR CORSON COUNTY. INCREASED POPS ALONG THE NORTHERN TIER FOR OVERNIGHT AND ADJUSTED HOURLY GRIDS. DEWPOINTS ARE ON THE INCREASE AS MOISTURE SURGES INTO THE REGION SO BUMPED THOSE UP AS WELL. WILL LIKELY SEE SEVERE WATCH EXTENDED EASTWARD IN THE NEXT HOUR OR TWO. && .PREVIOUS DISCUSSION... .SHORT TERM...TODAY THROUGH FRIDAY MORNING MAIN FORECAST CHALLENGE WILL BE THE POTENTIAL FOR SEVERE STORMS THIS EVENING AND INTO THE OVERNIGHT HOURS. WATER VAPOR IMAGERY SHOWS A SHORTWAVE OVER WESTERN MONTANA...MAKING ITS WAY NORTHEAST INTO NORTH DAKOTA. SURFACE OBS ARE SHOWING PRESSURE FALLS AHEAD OF THE SURFACE TROUGH WHICH IS CURRENTLY SITUATED ACROSS EASTERN MONTANA AND WYOMING. THIS TROUGH/COLD FRONT WILL MAKE ITS WAY EAST...ENTERING WESTERN SOUTH DAKOTA BY 00Z. DEWPOINTS ARE SLOW TO RESPOND THIS AFTERNOON...BUT MODELS STILL INDICATE INCREASING MOISTURE AHEAD OF THE FRONT...ENOUGH TO HELP DESTABILIZE THE ENVIRONMENT TONIGHT. NAM ML CAPE VALUES ARE STILL PROGGED TO BE IN THE 1000-1500 J/KG RANGE...ALONG WITH MID LEVEL LAPSE RATES RANGING FROM 7 TO 9 C/KM ACROSS THE REGION. THIS INSTABILITY WILL COME TOGETHER WITH A STRONG 50 KT LLJ TO FOCUS THUNDERSTORM DEVELOPMENT. THE MAIN THREATS WILL BE HAIL AND WIND...WITH AN EMPHASIS ON THE WIND...SINCE MODEL 0-6 KM BULK SHEAR VALUES WILL BE IN THE 50-60 KT RANGE AND 0-3 KM BULK SHEAR IN THE 40-50 KT RANGE. A HIGH SHEAR...HIGH CAPE ENVIRONMENT WOULD BE INDICATIVE OF A BOWING LINE OF STORMS...HOWEVER THE LIMITING FACTOR TONIGHT MAY BE THE CAPE...WHICH IS ON THE WEAKER END. BY THURSDAY AFTERNOON THE FRONT WILL BE EXITING THE CWA...WITH PERHAPS A FEW LINGERING SHOWERS IN THE EAST. WEST TO NORTHWEST WINDS WILL BE GUSTY ACROSS THE WESTERN CWA BEFORE HIGH PRESSURE MOVES IN THURSDAY NIGHT. ANOTHER SHORTWAVE WILL INFLUENCE THE REGION FRIDAY. MODEL TIMING DIFFERENCES STILL EXIST WITH THIS SYSTEM...BUT IT LOOKS AS THOUGH IT MAY BE ANOTHER NOCTURNAL SYSTEM. .LONG TERM...SATURDAY THROUGH WEDNESDAY A PROGRESSIVE MID LEVEL PATTERN LOOKS TO PERSIST THROUGH THE LONG RANGE...BUT MODEL AGREEMENT ON THE TIMING OF WAVES/VORTS IS MIDDLING AT BEST. THEREFORE TOOK MORE OF A GFS ENSEMBLE APPROACH TO POPS/WX AND TRIED TO MINIMIZE MENTION WHERE THERE IS SOME AGREEMENT ON DRY CONDITIONS BETWEEN THE GFS/ECMWF. THAT SAID MOST PERIODS STILL HAVE AT LEAST A SLIGHT CHANCE MENTION DUE TO FORECAST UNCERTAINTY. AS FOR TEMPERATURES THE MODEL BLEND LOOKED FINE FOR THE MOST PART. && .AVIATION... 00Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS VFR CONDITIONS ARE EXPECTED THROUGH TONIGHT. HOWEVER A COMPLEX OF STORMS IS EXPECTED TO TRAVEL IN THE VCNTY OF THE ND/SD BORDER LATE TNT. THESE STORMS COULD BE SEVERE AND COULD CAUSE AT LEAST A PERIOD OF IFR CONDITIONS AT BOTH KMBG/KABR TERMINALS. PATCHY MVFR CIGS COULD FOLLOW ANY PCPN/STORMS. WILL LEAVE OUT OF THE TAFS FOR NOW BUT WILL UPDATE AS NEEDED. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. && $$ UPDATE...WISE SHORT TERM...SERR LONG TERM...TDK AVIATION...WISE WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
132 PM CDT TUE JUN 12 2012 .DISCUSSION... UPDATED FOR 18Z AVIATION DISCUSSION && .PREV DISCUSSION... /ISSUED 1040 AM CDT TUE JUN 12 2012/ UPDATE... UPDATE TO ADJUST POPS FOR THE REMAINDER OF TODAY. DISCUSSION... A COLD FRONT IS CURRENTLY STRETCHED ACROSS NORTHERN PORTIONS OF THE MID SOUTH THIS MORNING. A DECAYING MESOSCALE CONVECTIVE SYSTEM (MCS) WILL CONTINUE TO WEAKEN WITH RAIN CHANCES DIMINISHING SLOWLY ACROSS THE SOUTH. WEAK SHORTWAVE DISTURBANCES EMBEDDED WITHIN NORTHWEST FLOW ALOFT COMBINED WITH THE SOUTHWARD MOVING FRONT AND AFTERNOON SURFACE HEATING MAY ALLOW FOR THE REDEVELOPMENT OF SCATTERED SHOWERS AND THUNDERSTORMS ACROSS EASTERN ARKANSAS AND NORTHERN MISSISSIPPI THIS AFTERNOON. AS INSTABILITY INCREASES CANNOT RULE OUT A STRONGER THUNDERSTORM...BUT THINK THE POTENTIAL FOR ANY SEVERE STORMS IS LOW AS SHEAR IS QUITE WEAK. UPDATED ZONES...GRIDS...AND HWO WILL BE SENT SHORTLY. JLH PREV DISCUSSION... /ISSUED 300 AM CDT TUE JUN 12 2012/ A COLD FRONT CURRENTLY STRETCHES FROM NEAR MOUNT VERNON ILLINOIS TO NEAR LITTLE ROCK ARKANSAS. CONVECTION THAT OCCURRED EARLIER THIS EVENING HAS PUSHED ALL THE WAY TO THE GULF COAST. SOME REDEVELOPMENT IS OCCURRING ACROSS SOUTHERN ARKANSAS IN RESPONSE TO A SHORTWAVE. THE MOVEMENT OF THESE STORMS ARE TO THE SOUTHEAST WHICH MOVES THEM INTO PHILLIPS COUNTY ARKANSAS AND PORTIONS OF NORTHWEST MISSISSIPPI. MODELS INDICATE FURTHER DEVELOPMENT COULD OCCUR TODAY ALONG AND AHEAD OF THE FRONT. HOWEVER THERE IS SOME QUESTION ON HOW WORKED OVER THE ATMOSPHERE IS FROM THIS EVENINGS CONVECTION. THE AREA WILL NOT BE AS UNSTABLE TODAY AS YESTERDAY AHEAD OF THE FRONT. THE 00Z NAM INDICATES SOME REDEVELOPMENT COULD OCCUR THIS MORNING ACROSS NORTH MISSISSIPPI BUT SHOULD PUSH SOUTH OF THE CWA BY EARLY AFTERNOON. THE LATEST RUC AND HRRR RUN SHOWS SOMETHING SIMILAR TO THE NAM. THE 00Z GFS DID NOT INITIALIZE WELL WITH WHAT IS CURRENTLY GOING THUS WILL NOT BE USED IN THE SHORT TERM. THUS WILL LOWER CHANCES FOR SHOWERS AND THUNDERSTORMS TO 40 PERCENT ACROSS MUCH OF NORTH MISSISSIPPI FOR MAINLY THIS MORNING WITH POSSIBLY LEAVING LIKELY POPS ACROSS PHILLIPS COUNTY AND PORTIONS OF NORTHWEST MISSISSIPPI THROUGH 7 AM. ELSEWHERE...WILL REMOVE MENTION OF PRECIPITATION. DRIER AIR WILL BEGIN TO FILTER INTO NORTHERN PORTIONS OF THE CWA BY THIS AFTERNOON. HIGHS WILL BE IN THE UPPER 80S. TONIGHT THROUGH THURSDAY NIGHT...HIGH PRESSURE WILL BUILD INTO THE AREA FROM THE OHIO VALLEY. DRIER AIR WILL FILTER INTO THE AREA BUT DO NOT EXPECT MUCH CHANGE IN AT LEAST HIGH TEMPERATURES. HIGHS WILL STILL BE IN THE MID 80S TO AROUND 90 THROUGH THE PERIOD. LOWS WILL BE COOLER WITH READINGS IN THE MID 50S TO MID 60S...POSSIBLY A TAD WARMER THURSDAY NIGHT AS WINDS TURN AROUND TO THE SOUTH. FRIDAY THROUGH EARLY NEXT WEEK...UPPER RIDGE MOVES OVER THE MIDSOUTH. 00Z GFS INDICATES DIURNAL HEATING COULD KICK OFF ISOLATED SHOWERS AND THUNDERSTORMS FRIDAY INTO THE WEEKEND. 00Z ECMWF SHOWS SOMETHING SIMILAR. FRIDAY SEEMS A LITTLE EARLY FOR MOISTURE RETURN TO BE ENOUGH TO CAUSE DIURNAL CONVECTION THUS WILL REMOVE POPS. OTHERWISE...WILL LEAVE CURRENT FORECAST AS IS. KRM && .AVIATION... 18Z TAF SET A COLD FRONT IS MOVING SLOWLY ACROSS THE MIDSOUTH TODAY. MOST OF THE RAIN HAS DISSIPATED AND SCATTERED MVFR CIGS ARE GRADUALLY IMPROVING TO VFR. VFR CONDS WILL PREVAIL TONIGHT THROUGH 18Z. WINDS WILL BECOME NNW THIS AFTERNOON AT ABT 8 KTS AND THEN DIMINISH TO AROUND 5 KTS OVERNIGHT. SJM && .PRELIMINARY POINT TEMPS/POPS... MEM 87 65 86 66 / 40 10 0 0 MKL 87 59 84 57 / 10 10 0 0 JBR 88 61 86 61 / 10 10 0 0 TUP 84 63 87 62 / 60 10 10 10 && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1040 AM CDT TUE JUN 12 2012 .UPDATE... UPDATE TO ADJUST POPS FOR THE REMAINDER OF TODAY. && .DISCUSSION... A COLD FRONT IS CURRENTLY STRETCHED ACROSS NORTHERN PORTIONS OF THE MID SOUTH THIS MORNING. A DECAYING MESOSCALE CONVECTIVE SYSTEM (MCS) WILL CONTINUE TO WEAKEN WITH RAIN CHANCES DIMINISHING SLOWLY ACROSS THE SOUTH. WEAK SHORTWAVE DISTURBANCES EMBEDDED WITHIN NORTHWEST FLOW ALOFT COMBINED WITH THE SOUTHWARD MOVING FRONT AND AFTERNOON SURFACE HEATING MAY ALLOW FOR THE REDEVELOPMENT OF SCATTERED SHOWERS AND THUNDERSTORMS ACROSS EASTERN ARKANSAS AND NORTHERN MISSISSIPPI THIS AFTERNOON. AS INSTABILITY INCREASES CANNOT RULE OUT A STRONGER THUNDERSTORM...BUT THINK THE POTENTIAL FOR ANY SEVERE STORMS IS LOW AS SHEAR IS QUITE WEAK. UPDATED ZONES...GRIDS...AND HWO WILL BE SENT SHORTLY. JLH && .PREV DISCUSSION... /ISSUED 300 AM CDT TUE JUN 12 2012/ A COLD FRONT CURRENTLY STRETCHES FROM NEAR MOUNT VERNON ILLINOIS TO NEAR LITTLE ROCK ARKANSAS. CONVECTION THAT OCCURRED EARLIER THIS EVENING HAS PUSHED ALL THE WAY TO THE GULF COAST. SOME REDEVELOPMENT IS OCCURRING ACROSS SOUTHERN ARKANSAS IN RESPONSE TO A SHORTWAVE. THE MOVEMENT OF THESE STORMS ARE TO THE SOUTHEAST WHICH MOVES THEM INTO PHILLIPS COUNTY ARKANSAS AND PORTIONS OF NORTHWEST MISSISSIPPI. MODELS INDICATE FURTHER DEVELOPMENT COULD OCCUR TODAY ALONG AND AHEAD OF THE FRONT. HOWEVER THERE IS SOME QUESTION ON HOW WORKED OVER THE ATMOSPHERE IS FROM THIS EVENINGS CONVECTION. THE AREA WILL NOT BE AS UNSTABLE TODAY AS YESTERDAY AHEAD OF THE FRONT. THE 00Z NAM INDICATES SOME REDEVELOPMENT COULD OCCUR THIS MORNING ACROSS NORTH MISSISSIPPI BUT SHOULD PUSH SOUTH OF THE CWA BY EARLY AFTERNOON. THE LATEST RUC AND HRRR RUN SHOWS SOMETHING SIMILAR TO THE NAM. THE 00Z GFS DID NOT INITIALIZE WELL WITH WHAT IS CURRENTLY GOING THUS WILL NOT BE USED IN THE SHORT TERM. THUS WILL LOWER CHANCES FOR SHOWERS AND THUNDERSTORMS TO 40 PERCENT ACROSS MUCH OF NORTH MISSISSIPPI FOR MAINLY THIS MORNING WITH POSSIBLY LEAVING LIKELY POPS ACROSS PHILLIPS COUNTY AND PORTIONS OF NORTHWEST MISSISSIPPI THROUGH 7 AM. ELSEWHERE...WILL REMOVE MENTION OF PRECIPITATION. DRIER AIR WILL BEGIN TO FILTER INTO NORTHERN PORTIONS OF THE CWA BY THIS AFTERNOON. HIGHS WILL BE IN THE UPPER 80S. TONIGHT THROUGH THURSDAY NIGHT...HIGH PRESSURE WILL BUILD INTO THE AREA FROM THE OHIO VALLEY. DRIER AIR WILL FILTER INTO THE AREA BUT DO NOT EXPECT MUCH CHANGE IN AT LEAST HIGH TEMPERATURES. HIGHS WILL STILL BE IN THE MID 80S TO AROUND 90 THROUGH THE PERIOD. LOWS WILL BE COOLER WITH READINGS IN THE MID 50S TO MID 60S...POSSIBLY A TAD WARMER THURSDAY NIGHT AS WINDS TURN AROUND TO THE SOUTH. FRIDAY THROUGH EARLY NEXT WEEK...UPPER RIDGE MOVES OVER THE MIDSOUTH. 00Z GFS INDICATES DIURNAL HEATING COULD KICK OFF ISOLATED SHOWERS AND THUNDERSTORMS FRIDAY INTO THE WEEKEND. 00Z ECMWF SHOWS SOMETHING SIMILAR. FRIDAY SEEMS A LITTLE EARLY FOR MOISTURE RETURN TO BE ENOUGH TO CAUSE DIURNAL CONVECTION THUS WILL REMOVE POPS. OTHERWISE...WILL LEAVE CURRENT FORECAST AS IS. KRM && .AVIATION... 12Z TAF SET A COLD FRONT HAS MOVED THROUGH JBR AND IS CURRENTLY APPROACHING MEM AND MKL. WINDS WILL BE NORTHERLY BEHIND AND FRONT TODAY WITH DRY CONDITIONS. FARTHER SOUTH...A FEW SHOWERS WILL LIKELY DEVELOP AROUND TUP. ONGOING CONVECTION LOOKS LIKE IT WILL STAY TO THE SOUTH AND EAST OF TUP...SO WITHOUT ANY ONGOING STORM TO BASE TIMING ON...JUST INCLUDED VCSH AFTER 16Z. ALL PRECIP WILL END TONIGHT AND HIGH PRESSURE WILL BUILD ACROSS THE MIDSOUTH RESULTING IN VFR CONDITIONS AREA WIDE. && .PRELIMINARY POINT TEMPS/POPS... MEM 87 65 86 66 / 40 10 0 0 MKL 87 59 84 57 / 10 10 0 0 JBR 88 61 86 61 / 10 10 0 0 TUP 84 63 87 62 / 60 10 10 10 && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
625 AM CDT TUE JUN 12 2012 .UPDATE...AVIATION DISCUSSION. && .PREV DISCUSSION... /ISSUED 300 AM CDT TUE JUN 12 2012/ A COLD FRONT CURRENTLY STRETCHES FROM NEAR MOUNT VERNON ILLINOIS TO NEAR LITTLE ROCK ARKANSAS. CONVECTION THAT OCCURRED EARLIER THIS EVENING HAS PUSHED ALL THE WAY TO THE GULF COAST. SOME REDEVELOPMENT IS OCCURRING ACROSS SOUTHERN ARKANSAS IN RESPONSE TO A SHORTWAVE. THE MOVEMENT OF THESE STORMS ARE TO THE SOUTHEAST WHICH MOVES THEM INTO PHILLIPS COUNTY ARKANSAS AND PORTIONS OF NORTHWEST MISSISSIPPI. MODELS INDICATE FURTHER DEVELOPMENT COULD OCCUR TODAY ALONG AND AHEAD OF THE FRONT. HOWEVER THERE IS SOME QUESTION ON HOW WORKED OVER THE ATMOSPHERE IS FROM THIS EVENINGS CONVECTION. THE AREA WILL NOT BE AS UNSTABLE TODAY AS YESTERDAY AHEAD OF THE FRONT. THE 00Z NAM INDICATES SOME REDEVELOPMENT COULD OCCUR THIS MORNING ACROSS NORTH MISSISSIPPI BUT SHOULD PUSH SOUTH OF THE CWA BY EARLY AFTERNOON. THE LATEST RUC AND HRRR RUN SHOWS SOMETHING SIMILAR TO THE NAM. THE 00Z GFS DID NOT INITIALIZE WELL WITH WHAT IS CURRENTLY GOING THUS WILL NOT BE USED IN THE SHORT TERM. THUS WILL LOWER CHANCES FOR SHOWERS AND THUNDERSTORMS TO 40 PERCENT ACROSS MUCH OF NORTH MISSISSIPPI FOR MAINLY THIS MORNING WITH POSSIBLY LEAVING LIKELY POPS ACROSS PHILLIPS COUNTY AND PORTIONS OF NORTHWEST MISSISSIPPI THROUGH 7 AM. ELSEWHERE...WILL REMOVE MENTION OF PRECIPITATION. DRIER AIR WILL BEGIN TO FILTER INTO NORTHERN PORTIONS OF THE CWA BY THIS AFTERNOON. HIGHS WILL BE IN THE UPPER 80S. TONIGHT THROUGH THURSDAY NIGHT...HIGH PRESSURE WILL BUILD INTO THE AREA FROM THE OHIO VALLEY. DRIER AIR WILL FILTER INTO THE AREA BUT DO NOT EXPECT MUCH CHANGE IN AT LEAST HIGH TEMPERATURES. HIGHS WILL STILL BE IN THE MID 80S TO AROUND 90 THROUGH THE PERIOD. LOWS WILL BE COOLER WITH READINGS IN THE MID 50S TO MID 60S...POSSIBLY A TAD WARMER THURSDAY NIGHT AS WINDS TURN AROUND TO THE SOUTH. FRIDAY THROUGH EARLY NEXT WEEK...UPPER RIDGE MOVES OVER THE MIDSOUTH. 00Z GFS INDICATES DIURNAL HEATING COULD KICK OFF ISOLATED SHOWERS AND THUNDERSTORMS FRIDAY INTO THE WEEKEND. 00Z ECMWF SHOWS SOMETHING SIMILAR. FRIDAY SEEMS A LITTLE EARLY FOR MOISTURE RETURN TO BE ENOUGH TO CAUSE DIURNAL CONVECTION THUS WILL REMOVE POPS. OTHERWISE...WILL LEAVE CURRENT FORECAST AS IS. KRM .AVIATION... 12Z TAF SET A COLD FRONT HAS MOVED THROUGH JBR AND IS CURRENTLY APPROACHING MEM AND MKL. WINDS WILL BE NORTHERLY BEHIND AND FRONT TODAY WITH DRY CONDITIONS. FARTHER SOUTH...A FEW SHOWERS WILL LIKELY DEVELOP AROUND TUP. ONGOING CONVECTION LOOKS LIKE IT WILL STAY TO THE SOUTH AND EAST OF TUP...SO WITHOUT ANY ONGOING STORM TO BASE TIMING ON...JUST INCLUDED VCSH AFTER 16Z. ALL PRECIP WILL END TONIGHT AND HIGH PRESSURE WILL BUILD ACROSS THE MIDSOUTH RESULTING IN VFR CONDITIONS AREA WIDE. && .PRELIMINARY POINT TEMPS/POPS... MEM 88 65 86 66 / 20 10 0 0 MKL 88 59 84 57 / 10 10 0 0 JBR 89 61 86 61 / 10 10 0 0 TUP 87 63 87 62 / 40 10 10 10 && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
300 AM CDT TUE JUN 12 2012 .DISCUSSION... A COLD FRONT CURRENTLY STRETCHES FROM NEAR MOUNT VERNON ILLINOIS TO NEAR LITTLE ROCK ARKANSAS. CONVECTION THAT OCCURRED EARLIER THIS EVENING HAS PUSHED ALL THE WAY TO THE GULF COAST. SOME REDEVELOPMENT IS OCCURRING ACROSS SOUTHERN ARKANSAS IN RESPONSE TO A SHORTWAVE. THE MOVEMENT OF THESE STORMS ARE TO THE SOUTHEAST WHICH MOVES THEM INTO PHILLIPS COUNTY ARKANSAS AND PORTIONS OF NORTHWEST MISSISSIPPI. MODELS INDICATE FURTHER DEVELOPMENT COULD OCCUR TODAY ALONG AND AHEAD OF THE FRONT. HOWEVER THERE IS SOME QUESTION ON HOW WORKED OVER THE ATMOSPHERE IS FROM THIS EVENINGS CONVECTION. THE AREA WILL NOT BE AS UNSTABLE TODAY AS YESTERDAY AHEAD OF THE FRONT. THE 00Z NAM INDICATES SOME REDEVELOPMENT COULD OCCUR THIS MORNING ACROSS NORTH MISSISSIPPI BUT SHOULD PUSH SOUTH OF THE CWA BY EARLY AFTERNOON. THE LATEST RUC AND HRRR RUN SHOWS SOMETHING SIMILAR TO THE NAM. THE 00Z GFS DID NOT INITIALIZE WELL WITH WHAT IS CURRENTLY GOING THUS WILL NOT BE USED IN THE SHORT TERM. THUS WILL LOWER CHANCES FOR SHOWERS AND THUNDERSTORMS TO 40 PERCENT ACROSS MUCH OF NORTH MISSISSIPPI FOR MAINLY THIS MORNING WITH POSSIBLY LEAVING LIKELY POPS ACROSS PHILLIPS COUNTY AND PORTIONS OF NORTHWEST MISSISSIPPI THROUGH 7 AM. ELSEWHERE...WILL REMOVE MENTION OF PRECIPITATION. DRIER AIR WILL BEGIN TO FILTER INTO NORTHERN PORTIONS OF THE CWA BY THIS AFTERNOON. HIGHS WILL BE IN THE UPPER 80S. TONIGHT THROUGH THURSDAY NIGHT...HIGH PRESSURE WILL BUILD INTO THE AREA FROM THE OHIO VALLEY. DRIER AIR WILL FILTER INTO THE AREA BUT DO NOT EXPECT MUCH CHANGE IN AT LEAST HIGH TEMPERATURES. HIGHS WILL STILL BE IN THE MID 80S TO AROUND 90 THROUGH THE PERIOD. LOWS WILL BE COOLER WITH READINGS IN THE MID 50S TO MID 60S...POSSIBLY A TAD WARMER THURSDAY NIGHT AS WINDS TURN AROUND TO THE SOUTH. FRIDAY THROUGH EARLY NEXT WEEK...UPPER RIDGE MOVES OVER THE MIDSOUTH. 00Z GFS INDICATES DIURNAL HEATING COULD KICK OFF ISOLATED SHOWERS AND THUNDERSTORMS FRIDAY INTO THE WEEKEND. 00Z ECMWF SHOWS SOMETHING SIMILAR. FRIDAY SEEMS A LITTLE EARLY FOR MOISTURE RETURN TO BE ENOUGH TO CAUSE DIURNAL CONVECTION THUS WILL REMOVE POPS. OTHERWISE...WILL LEAVE CURRENT FORECAST AS IS. KRM && .AVIATION... 06Z TAF SET VFR CONDITIONS WILL DOMINATE...HOWEVER...SOME LOCATIONS MAY HAVE SOME FOG IN THE MORNING. IF ANY FOG DOES DEVELOP EXPECT IT TO BE MVFR CONDITIONS. WINDS LIGHT AND WILL SWITCH TO NORTH BY MORNING IN ENTIRE REGION. AFTERNOON THUNDERSTORMS ARE TUESDAY ARE POSSIBLE...HOWEVER NOT CONFIDENT ENOUGH WITH TIMING OR LOCATION AS STORMS WILL BE AT BEST SCATTERED. && .PRELIMINARY POINT TEMPS/POPS... MEM 88 65 86 66 / 20 10 0 0 MKL 88 59 84 57 / 10 10 0 0 JBR 89 61 86 61 / 10 10 0 0 TUP 87 63 87 62 / 40 10 10 10 && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1235 AM CDT TUE JUN 12 2012 .UPDATE...AVIATION DISCUSSION. && .PREV DISCUSSION... /ISSUED 1043 PM CDT MON JUN 11 2012/ EARLIER FORECAST IS BASICALLY ON TRACK...ALTHOUGH DID UPDATE TO ADJUST POPS SLIGHTLY BASED ON THE LATEST HRRR MODEL. INCREASED THE POPS SLIGHTLY FOR TONIGHT MAINLY FROM EAST CENTRAL AR INTO NORTHWEST MS AND LOWERED THEM SLIGHTLY MOST OTHER LOCATIONS. THUNDERSTORMS ASSOCIATED WITH THE MESOSCALE CONVECTIVE SYSTEM THAT PLOWED THROUGH THE MIDSOUTH EARLIER TODAY NOW STRETCH FROM NORTHERN LA ACROSS CENTRAL MS INTO CENTRAL AL. THE ATMOSPHERE ACROSS THE MIDSOUTH IS RAIN COOLED WITH SURFACE BASED INSTABILITY NIL. HOWEVER...ELEVATED INSTABILITY OF ABOUT 1500 TO 2000 J/KG EXIST TO OUR WEST AND SOUTHWEST WITH 00Z 850 MB ANALYSIS SHOWING A SOUTHWEST LY LOW LEVEL FLOW. SCATTERED SHOWERS AND THUNDERSTORMS HAVE ALREADY BEGUN TO FORM IN CENTRAL AR. THE HRRR MODEL INDICATES THUNDERSTORMS WILL CONTINUE TO INCREASE THROUGH THIS AREA (POSSIBLY DEVELOPING INTO A MESOSCALE CONVECTIVE SYSTEM) AND SLIDE TO THE SOUTHEAST SKIRTING EAST-CENTRAL AR AND NORTHWEST MS. A FEW STRONG ELEVATED THUNDERSTORMS STILL WITH WIND GUSTS UP TO 45 MPH AND SMALL HAIL STILL LOOK POSSIBLE MAINLY FROM EAST CENTRAL AR INTO PORTIONS OF NORTH MS. OTHERWISE A COLD FRONT WILL MOVE INTO NORTHEAST AR AND THE MO BOOTHEEL BY LATE TONIGHT...A FEW SHOWERS AND THUNDERSTORMS MAY DEVELOP ALONG AND AHEAD OF THE FRONT LATER TONIGHT. TEMPERATURES HAVE COOLED INTO THE MIDDLE 60S ACROSS MUCH OF THE MIDSOUTH. READINGS MAY DROP A DEGREE OR TWO MORE BUT MAINLY WILL REMAIN STEADY. JCL PREV DISCUSSION... /ISSUED 711 PM CDT MON JUN 11 2012/ UPDATED TO LOWER POPS ACROSS THE MID SOUTH FOR THIS EVENING AND CLEAR SEVERE THUNDERSTORM WATCH #373 FOR THE ENTIRE AREA. THE SEVERE LINE OF THUNDERSTORMS THAT MOVES SOUTH ACROSS THE AREA THIS AFTERNOON AND EVENING HAS NOW EXITED OUR AREA. STRATIFORM RAIN BEHIND THE SEVERE CONVECTION WILL PERSIST FOR A FEW HOURS AT MOST AND MAINTAINED LIKELY POPS OVER NORTH MISSISSIPPI TO ACCOUNT FOR THIS. ELSEWHERE HAVE LOWERED POPS FOR THIS EVENING. LATER TONIGHT...LATEST HIGH RESOLUTION RAPID REFRESH MODEL INDICATES ADDITIONAL DEVELOPMENT OF CONVECTION OVER WESTERN ARKANSAS ALONG STALLED OUTFLOW BOUNDARY. THIS CONVECTION MAY MOVE BACK OVER SOUTHERN PORTIONS OF THE FORECAST AREA AFTER MIDNIGHT. THE CURRENT FORECAST HAD ACCOUNTED FOR THIS ACTIVITY BUT CONFIDENCE IS RATHER LOW. THE ATMOSPHERE MAY BE TOO WORKED OVER FROM THIS EVENINGS CONVECTION OR NEW CONVECTION MAY BE ELEVATED OVER THE DECAYING COLD POOL. LATER UPDATES MAY BE NEEDED AS THE EVENTUAL EVOLUTION BECOMES MORE CLEAR. UPDATED ZONES...GRIDS...AND HWO HAVE BEEN SENT. JLH PREV DISCUSSION... /ISSUED 320 PM CDT MON JUN 11 2012/ A SEVERE FORWARD PROPAGATING MESOSCALE CONVECTIVE SYSTEM (MCS) CURRENTLY ACROSS NORTHWEST TENNESSEE INTO EASTERN ARKANSAS WILL CONTINUE TO RACE SOUTHEASTWARD THROUGH THE REMAINDER OF THE AFTERNOON AND EVENING HOURS. THIS LINE HAS HAD A HISTORY OF WIND DAMAGE AND THE PRE-CONVECTIVE ENVIRONMENT REMAIN FAVORABLE FOR CONTINUED WIND DAMAGE WITH MLCAPES IN EXCESS OF 4000 J/KG. THIS MCS CONTINUES TO MOVE ALONG THE NORTHEAST PERIPHERY OF STRONGER CAPPING/EML OVER THE ARKLATEX REGION. THIS LINE OF SEVERE THUNDERSTORMS SHOULD MOVE THROUGH THE REMAINDER OF THE FORECAST AREA THROUGH THE EVENING. LATER TONIGHT...THE FORECAST BECOMES MORE UNCERTAIN AS THE ATMOSPHERE WILL INITIALLY BE WORKED OVER FROM THIS AFTERNOONS MCS. THE CONVECTIVE OUTFLOW BOUNDARY SLOWS QUITE A BIT ACROSS NORTH- CENTRAL ARKANSAS AND THIS AREA MAY BE PRIMED FOR REDEVELOPMENT LATER THIS EVENING...WITH THE ATMOSPHERE POTENTIALLY RELOADING ACROSS SOUTHWESTERN PORTIONS OF THE AREA. LATEST MODEL GUIDANCE HINTS AT THIS OCCURRENCE...BUT TIMING CONTINUES TO BE A PROBLEM AS LATEST HRRR IS FASTER WITH MOST CONVECTION PRIOR TO 06Z AND ALL OTHER MODEL GUIDANCE NOW SLOWER AND LINGERING CONVECTION THROUGH THE NIGHT OVER THESE LOCATIONS. PLAN TO CARRY LIKELY POPS OVER THE SOUTH AND WEST AFTER 06Z AND WILL MAINTAIN A SEVERE THREAT FOR DAMAGING WINDS AND LARGE HAIL. OVERNIGHT ACTIVITY SHOULD WANE LATE TONIGHT WITH SCATTERED THUNDERSTORM REDEVELOPMENT POSSIBLE ALONG A SOUTHWARD MOVING COLD FRONT ALONG THE I-40 CORRIDOR BY MID MORNING. THIS FRONT WILL CONTINUE TO DROP SOUTH THROUGH EASTERN ARKANSAS AND NORTHERN MISSISSIPPI BY AFTERNOON WITH THUNDERSTORM ACTIVITY BECOMING MORE NUMEROUS IN COVERAGE. THE ATMOSPHERE WILL AGAIN DESTABILIZE OVER THE SOUTHERN HALF OF THE AREA WITH STRONG TO POTENTIALLY SEVERE STORMS AGAIN POSSIBLE. THE COLD FRONT WILL MOVE THROUGH THE MID SOUTH BY TUESDAY NIGHT WITH SURFACE HIGH PRESSURE BUILDING OVER THE AREA. THE FRONT SHOULD STALL ACROSS CENTRAL MISSISSIPPI AS UPPER LEVEL HEIGHTS RISE. DRY AND VERY WARM WEATHER CAN BE EXPECTED WEDNESDAY THROUGH FRIDAY MORNING. THE FRONT WILL RETURN BACK TO THE NORTH AS A WARM FRONT BY FRIDAY ALLOWING FOR A DEEP TROPICAL MOISTURE TO ADVANCE BACK INTO THE MID SOUTH. ISOLATED SHOWERS AND THUNDERSTORMS WILL AGAIN BE POSSIBLE DURING PEAK HEATING ON BOTH FRIDAY AND SATURDAY. A DRIER AIRMASS WILL WORK INTO THE AREA BY SUNDAY HELPING TO LIMIT DIURNAL CONVECTION. TEMPERATURES WILL REMAIN SEASONALLY WARM WITH INCREASING HUMIDITY LEVELS THROUGH THE END OF THE EXTENDED FORECAST PERIOD. JLH .AVIATION... 06Z TAF SET VFR CONDITIONS WILL DOMINATE...HOWEVER...SOME LOCATIONS MAY HAVE SOME FOG IN THE MORNING. IF ANY FOG DOES DEVELOP EXPECT IT TO BE MVFR CONDITIONS. WINDS LIGHT AND WILL SWITCH TO NORTH BY MORNING IN ENTIRE REGION. AFTERNOON THUNDERSTORMS ARE TUESDAY ARE POSSIBLE...HOWEVER NOT CONFIDENT ENOUGH WITH TIMING OR LOCATION AS STORMS WILL BE AT BEST SCATTERED. && .PRELIMINARY POINT TEMPS/POPS... MEM 66 87 66 91 / 10 10 10 10 MKL 60 84 60 88 / 10 10 10 10 JBR 63 86 62 89 / 10 10 10 10 TUP 67 90 63 90 / 20 10 10 10 && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
932 PM CDT WED JUN 13 2012 .UPDATE... NO CHANGES TO FORECAST. && .DISCUSSION... UPPER SHORTWAVE WAS MOVING INTO WEST TEXAS THIS EVENING...HOWEVER CONVECTIVE DEVELOPMENT WAS SCARCE...WITH ONLY SCATTERED SHOWERS IN THE TRANSPECOS TRYING TO CROSS THE PECOS RIVER IN WESTERN CROCKETT COUNTY. WHILE CHANCE OF STORMS APPEARS REMOTE TONIGHT WITH INCREASING CAP...WILL CONTINUE TO KEEP A SLIGHT CHANCE OF STORMS AS UPPER SHORTWAVE MOVES ACROSS THE REGION. PREVIOUS GFS AND NAM MODELS WERE INDICATING THE BEST CHANCE OF RAIN AFTER 10 PM. 04 && .PREV DISCUSSION... /ISSUED 559 PM CDT WED JUN 13 2012/ DISCUSSION... SEE 00Z AVIATION DISCUSSION BELOW. AVIATION... VFR CONDITIONS ARE EXPECTED THE NEXT 24 HOURS. WINDS WILL BE SOUTH AT 10 TO 15 KNOTS WITH A FEW GUSTS TO 20 KNOTS. WATCHING A FEW TSTMS OVER SOUTHWEST TEXAS. THIS ACTIVITY WILL PROBABLY REMAIN WELL WEST OF THE TERMINALS. 21 PREV DISCUSSION... /ISSUED 348 PM CDT WED JUN 13 2012/ SHORT TERM... WE HAD ISOLATED WEAK CONVECTION EARLY TODAY BUT THIS HAS SINCE DISSIPATED. SKIES HAVE BECOME MOSTLY CLEAR TO PARTLY CLOUDY ACROSS THE CWA LIKELY IN RESPONSE TO SUBSIDENCE IN THE WAKE OF THE DEPARTING MCV ALONG THE RED RIVER VALLEY. A WEAK SURFACE...YET DISCERNIBLE...BOUNDARY STILL EXISTS OVER THE SOUTHWEST CWA PER THE KSJT WSR-88D BUT THIS FEATURE REMAINS BENIGN AT THIS TIME. LOOKING WEST...MID LEVEL RADAR ECHOES HAVE BEEN INCREASING ACROSS SOUTHWEST TX THIS AFTERNOON AHEAD OF AN APPROACHING SHORTWAVE. AS THIS SYNOPTIC SCALE ASCENT OVERSPREADS THE AREA AND SURFACE TEMPS WARM INTO THE MID/UPPER 90S...I ANTICIPATE CONVECTION DEVELOPING IN THE VICINITY OF THE CWA. CONFIDENCE IS FAIRLY LOW THAT WE WILL SEE WIDESPREAD THUNDERSTORMS BUT SEVERAL VERSIONS OF THE HIRES WRF AND THE HRRR ALL AGREE IN THUNDERSTORMS FORMING OVER THE CENTRAL/EASTERN COUNTIES. A LOOK AT THE SPC MESO ANALYSIS PAGE DEPICTS SBCAPE VALUES ON THE ORDER OF 2500-3500 J/KG WITH EFFECTIVE SHEAR VALUES BETWEEN 40-50 KTS. THE QUESTION WILL BE WHETHER OR NOT THE CAP WILL GIVE WAY. THUS...WE DO HAVE A CONDITIONAL THREAT FOR SEVERE WEATHER BUT I AM PLAYING THIS RATHER CONSERVATIVE FOR NOW THINKING THAT THE CAP WILL HOLD FOR THE MOST PART AND ANY CONVECTIVE INITIATION WILL LIKELY BE DELAYED UNTIL WELL AFTER PEAK HEATING. THUS...I AM ONLY CARRYING 20 POPS FOR THE PERIOD BEGINNING AT 00Z. OVERNIGHT TEMPS WILL FALL INTO THE LOWER 70S /BUT WILL LIKELY BE LOWER IF CONVECTION DOES DEVELOP/. GENERALLY DRY AND WARM CONDITIONS ARE EXPECTED FOR THURSDAY WITH SOUTH WINDS INCREASING TO 10-20 MPH ACROSS THE CWA. HIGHS ARE EXPECTED TO BE IN THE MID/UPPER 90S. JOHNSON LONG TERM... THURSDAY NIGHT INTO FRIDAY...THE UPPER LEVEL LOW THAT IS CURRENTLY OVER SOUTHERN CALIFORNIA TODAY WILL BE ENVELOPED BY ANOTHER LOW THAT WILL MOVE SOUTH ALONG THE CALIFORNIA COAST. THERE WILL BE AN UPPER LEVEL TROUGH OVER THE GULF COAST REGION AS WELL WHILE WEST CENTRAL TEXAS WILL BE IN BETWEEN UNDERNEATH RIDGING. FOR THIS REASON...WILL GO WITH TEMPERATURES SLIGHTLY WARMER THAN GUIDANCE FOR FRIDAY AND SATURDAY. HAVE NOT EXPANDED ANY OF THE INHERITED POPS FRIDAY AFTERNOON AND EVENING. IT STILL APPEARS THAT THE LOW WILL BE TOO FAR WEST TO DIRECTLY INFLUENCE US...AND THAT MOST OF THE CONVECTION WILL GET GOING IN THE HIGHER TERRAIN OF THE WEST TEXAS AREA...THEN MOVE SLOWLY TO THE NORTHEAST DURING THE EVENING HOURS...POSSIBLY MAKING THEIR WAY INTO OUR WESTERN TIER OF COUNTIES BEFORE DISSIPATING. THE UPPER LEVEL RIDGING EXPANDS THROUGH THE WEEKEND ACROSS TEXAS AND THE REST OF THE SOUTHWESTERN U.S. THIS WILL PUSH THE MID/UPPER LEVEL LOW BACK OUT TO THE PACIFIC...AND KEEP OUR TEMPERATURES WARMER THAN NORMAL WITH LITTLE CHANCE FOR PRECIPITATION. BY TUESDAY OF NEXT WEEK...A WEAK MID/UPPER LEVEL TROUGH DEVELOPS ACROSS THE EASTERN HALF OF TEXAS...AND LOOKS TO DRIFT SLOWLY WEST/SOUTHWEST ACROSS THE SOUTHERN HALF OF THE STATE. THIS COULD RESULT IN SOME LOWERED TEMPERATURES...AND THE GFS/ECMWF ALSO TRY TO SHOW SOME SHRA/TSRA DEVELOPING ACROSS OUR SOUTHEASTERN COUNTIES. WILL HOLD OFF ON INTRODUCING ANY WX AT THIS TIME...BUT IT WILL BE WORTH WATCHING. 20 && .PRELIMINARY POINT TEMPS/POPS... ABILENE 92 72 93 72 94 / 20 20 10 10 10 SAN ANGELO 97 73 98 73 98 / 20 20 10 10 10 JUNCTION 98 74 98 73 94 / 20 20 10 10 10 && .SJT WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 99/04
AREA FORECAST DISCUSSION...UPDATED
NWS AMARILLO TX
914 PM CDT WED JUN 13 2012 .UPDATE... THE 00Z KAMA /AND KDDC/ SOUNDINGS SHOWED A PRONOUNCED CAPPING INVERSION AROUND 700MB IN PLACE ACROSS THE AREA...WHICH IS ALSO INDICATED BY LAPS DATA. THIS CAPPING ALONG WITH A LACK OF ANY SIGNIFICANT FORCING HAS KEPT THE CWA CONVECTION FREE SO FAR THIS EVENING. CU THAT TRIED TO GROW ALONG A WEAK NORTH/SOUTH LOW-LEVEL CONVERGENT AXIS EAST OF AN AMARILLO TO GUYMON LINE HAS RECENTLY DISSIPATED WITH ONSET OF NOCTURNAL COOLING AND RESULTANT STRENGTHENING CIN. A FEW THUNDERSTORMS THAT DEVELOPED OVER THE MOUNTAINS OF NM CONTINUE TO SLOWLY WORK EAST ACROSS EASTERN NM...WHILE CONVECTION THAT DEVELOPED ALONG A SURFACE TROUGH OVER SOUTHEAST CO INTO WESTERN KS HAS DISSIPATED. THERE IS STILL SOME POTENTIAL FOR THUNDERSTORMS ACROSS THE PANHANDLES TONIGHT...HOWEVER BELIEVE COVERAGE WILL BE FAIRLY ISOLATED. A WEAK MID-LEVEL SHORTWAVE APPEARS TO BE MOVING EAST ACROSS CENTRAL NM PER WATER VAPOR IMAGERY...AND A 40 KT SOUTHERLY LLJ IS EXPECTED TO DEVELOP ACROSS THE EASTERN HALF OF THE FORECAST AREA TONIGHT. WEAK FORCING FROM THE SHORTWAVE AND/OR WARM AIR ADVECTION/MOISTURE ADVECTION ALONG THE LLJ AXIS MAY ALLOW CONVECTION TO WORK IN FROM NM/FAR SOUTHERN CO OR FOR NEW CONVECTION TO DEVELOP. NORTHWEST AREAS WILL BE FAVORED FOR ANY ISOLATED STORMS THROUGH MIDNIGHT AS STORMS MAY WORK IN FROM THE WEST...WITH THE FOCUS THEN SHIFTING TO THE EASTERN HALF TO TWO THIRDS OF THE CWA OVERNIGHT ALONG THE LLJ AXIS. HOWEVER...BELIEVE SHORTWAVE RIDGING AND CAPPING IN PLACE WILL KEEP ANY CONVECTION ISOLATED...WITH FORECAST SOUNDINGS SUGGESTING THAT THE MID- LEVEL CAPPING WILL LIKELY MAKE IT TOUGH EVEN FOR ELEVATED CONVECTION TO DEVELOP TONIGHT. WILL KEEP THUNDERSTORM CHANCES IN THE FORECAST GIVEN THE LLJ PRESENCE...WEAK SHORTWAVE OVER NM...AND SOME LINGERING CONVECTION SLOWLY WORKING THIS WAY...BUT KEEP THEM ON THE LOW SIDE DUE TO ANTICIPATED WEAK FORCING AND CAPPING CONCERNS. IF STORMS ARE ABLE TO OVERCOME THE CAP...THERE WILL BE AMPLE INSTABILITY TO TAP INTO ABOVE IT /MUCAPES OF 2000-3000 J/KG/ TO SUPPORT PRIMARILY A LARGE HAIL THREAT GIVEN EXPECTED ELEVATED NATURE OF STORMS...ALTHOUGH CAN/T RULE OUT SOME STRONG WINDS. VARIOUS SHORT TERM MODELS ARE STILL GIVING VERY MIXED SIGNALS FOR THUNDERSTORM POTENTIAL OVERNIGHT...RANGING FROM VIRTUALLY NO ACTIVITY INDICATED BY THE HRRR TO A SOLID LINE OF STORMS DEVELOPING IN THE OUN WRF. AM SIDING WITH THE MUCH LESSER COVERAGE/CHANCES DUE TO THE REASONS STATED ABOVE. ALSO...NOT ANTICIPATING ANY SIGNIFICANT COLD POOL PRESENCE TO AID IN MORE WIDESPREAD DEVELOPMENT TONIGHT GIVEN VERY ISOLATED NATURE OF ONGOING CONVECTION. SO TO SUMMARIZE...SOME POTENTIAL FOR ISOLATED STORMS WILL CONTINUE TONIGHT BUT EXPECT COVERAGE TO BE PRETTY MINIMAL. HOWEVER IF STORMS DO DEVELOP...THEY COULD BE STRONG OR SEVERE WITH HAIL THE MAIN CONCERN. KB && .PREV DISCUSSION... /ISSUED 633 PM CDT WED JUN 13 2012/ AVIATION... AN UPPER RIDGE OVER THE PANHANDLES THIS EVENING WILL GIVE WAY TO AN UPPER TROUGH AFTER 06Z THURSDAY. VFR CONDITIONS ARE EXPECTED TO PREVAIL...HOWEVER SOME CONVECTION COULD POSSIBLY DEVELOP AFTER 06Z THURSDAY IN RESPONSE TO THE UPPER TROUGH. THE AMARILLO TAF SITE WOULD BE THE TAF SITE WHICH COULD BE AFFECTED LATER TONIGHT BY ANY CONVECTION. WILL HOLD OFF NOW MENTIONING IN THE TAF FORECAST AS CONFIDENCE REMAINS LOW. SOUTHERLY TO SOUTHEASTERLY WINDS 10 TO 20 KNOTS WITH SOME OCCASIONAL HIGHER GUSTS WILL BE THE RULE THROUGH 00Z FRIDAY. SCHNEIDER PREV DISCUSSION... /ISSUED 337 PM CDT WED JUN 13 2012/ DISCUSSION... THUNDERSTORMS ARE STARTING TO DEVELOP OVER THE MOUNTAINS IN NEW MEXICO. MEANWHILE...SCATTERED AND BROKEN CLOUD COVER OVER THE WESTERN TEXAS PANHANDLE HAS LIMITED THE HEATING WHERE THE HIGHEST INSTABILITY IS FORECAST TO BE FOR THIS EVENING. THIS EVENING...STILL SOME QUESTION ON THE CONVECTIVE POTENTIAL. MODELS...SPECIFICALLY THE NAM AND RAP...SHOW LARGE CAPE VALUES...1500 TO 3000 J/KG...AND MODEST SHEAR VALUES OF 20 TO 30 KT. HOWEVER...SUSPECT THAT THE CAP IS STILL IN PLACE...ESPECIALLY IN LOCATIONS THAT SAW CLOUD COVER MOST OF THE DAY. EARLIER RUNS OF THE RAP WERE SHOWING CONVECTIVE DEVELOPMENT NEAR KAMA...HOWEVER...EXPECT THAT THIS WAS OVER ESTIMATING THE AMOUNT OF LIFT ALONG THE NOW RATHER POORLY DEFINED SURFACE TROUGH. SO EXPECT THE MAIN AREA OF THUNDERSTORMS WILL ONCE AGAIN BE STORMS MOVING IN FROM NM. TOMORROW...MODELS INDICATE THE DRYLINE SHOULD SHIFT FURTHER EAST...WITH THE GFS EVEN SHOWING THE DRYLINE MOVING INTO THE FAR WESTERN PANHANDLES. WITH THE DRYLINE CURRENTLY SO FAR WEST...NOT CERTAIN THAT IT WILL BE ABLE TO PUSH THIS FAR EAST. WHEREVER IT STALLS...IT SHOULD BE THE MAIN FOCUS FOR THUNDERSTORM DEVELOPMENT TOMORROW. WITH EVEN WEAKER UPPER LEVEL STEERING FLOW TOMORROW...STORMS MAY NOT PROPAGATE VERY FAR FROM THE DRYLINE. FRIDAY THROUGH MONDAY...THE MAIN FOCUS THROUGH THIS PERIOD IS THE BROAD UPPER LEVEL TROUGH CURRENTLY OVER CA...EXPECTED TO DIG SOUTH THROUGH FRIDAY. HOWEVER THEN...BOTH THE GFS AND ECMWF SHOW THE TROUGH SLOWLY RETROGRESSING THROUGH THE WEEKEND AS A HIGH BUILDS IN OVER TX...AND THEN RETROGRESSES ITSELF. WHAT MAKES THIS PATTERN UNUSUAL IS THAT AT THE SAME TIME...THE MODEL SOLUTIONS SHOW A SLOW...BUT PROGRESSIVE...UPPER LEVEL TROUGH MOVING EAST ACROSS THE NORTHERN TIER OF THE U.S. THIS IS A BIG CHANGE FROM PREVIOUS RUNS OF MODELS...WHICH SHOWED THE BROAD TROUGH STAYING NEARLY STATIONARY AS A SERIES OF SHORT WAVE TROUGHS LIFT NE OVER THE SOUTHERN PLAINS...BRINGING ABUNDANT CHANCES FOR PRECIPITATION THROUGH THE WEEKEND. WITH THE NEW SOLUTION...THERE ARE RATHER LIMITED CHANCES FOR PRECIPITATION FOR THE REGION. TUESDAY...IN ANOTHER STARK CONTRAST FROM PREVIOUS FORECASTS...THERE IS NO HINT OF THE COLD FRONT MOVING THROUGH THE REGION TUESDAY. THIS SEEMS REASONABLE AS IT IS DIFFICULT THIS TIME OF YEAR TO GET STRONG COLD FRONTS THIS FAR SOUTH WITH OUT A SIGNIFICANT UPPER LEVEL LOW OR TROUGH. JOHNSON FIRE WEATHER... ABOVE NORMAL MOISTURE WILL REMAIN IN PLACE OVER THE NEXT SEVERAL DAYS...KEEPING RELATIVE HUMIDITY VALUES WELL ABOVE 20 PERCENT FOR MUCH OF THE REGION. THE ONE EXCEPTION IS TOMORROW...WHEN A WEAK DRYLINE COULD SNEAK INTO THE FAR WESTERN TEXAS PANHANDLE...RESULTING IN MINIMUM RELATIVE HUMIDITY VALUES NEAR 20 PERCENT...WITH SOUTHERLY WINDS OF 15 TO 20 MPH. HOWEVER...RECENT RAINS SHOULD PRECLUDE ANY ELEVATED FIRE WEATHER CONDITIONS FOR TOMORROW. JOHNSON && .AMA WATCHES/WARNINGS/ADVISORIES... TX...NONE. OK...NONE. && $$ 11/08
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
750 PM CDT WED JUN 13 2012 .UPDATE... AXIS OF ENHANCED CU WAS FOUND STRETCHING FROM SILVERTON SOUTHEAST TO SPUR AND ASPERMONT ALONG THE WESTERN TERMINUS OF A SURFACE MESOHIGH LEFTOVER FROM A COMPLEX OF STORMS EARLIER TODAY. A FEW OF THESE TCU HAVE ARE OCCASIONALLY MATURING INTO GREATER DEPTHS WITH ECHOES EVIDENT ON THE REGIONAL 88D MOSAIC...BUT MANY OF THESE ARE HAVING GREAT DIFFICULTY IN SUSTAINING THEMSELVES DUE TO MARGINAL LL CONVERGENCE AND MORE IMPORTANTLY A PRONOUNCED CAP THAT WAS DIRECTLY SAMPLED BY AIRCRAFT IN/NEAR LBB IN RECENT HOURS. RECENT RUNS OF THE HRRR/TTU-WRF/OUN-WRF TEND ARE FAVORING SOME DEGREE OF STORMS MOVING INTO THE PLAINS OF ERN NM THIS EVENING BEFORE CONTINUING INTO THE SOUTH PLAINS. ALTHOUGH THIS ACTIVITY WILL ENTER A PROGRESSIVELY HOSTILE ENVIRONMENT FOR STORMS /E.G. UPPER RIDGING AND A REDUCED UPSLOPE FLOW COMPONENT/...CURRENT FEELING IS THAT AS THE LATE EVENING AND OVERNIGHT WEAR ON STORMS SHOULD DOT THE CWA. REASONING FOR THIS IS TIED TO A SUBTLE S/W TROUGH EVIDENT ON WATER VAPOR IMAGERY IN CENTRAL NEW MEXICO. DRYING/SUBSIDENCE IN THE WAKE OF THIS WAVE HAS BEEN OBSERVED SINCE LATE THIS MORNING AND SOME CONTRIBUTION OF LIFT WILL BE DEALT TO THE SOUTH PLAINS AS THIS FEATURE CRESTS THE AFOREMENTIONED RIDGE. ADD TO THIS A DEVELOPING NOCTURNAL LLJ AND THE POTENTIAL FOR ELEVATED CONVECTION REMAINS PLAUSIBLE. HAVE UPDATED THE FCST TO DELAY MENTION OF POPS UNTIL LATER THIS EVENING OVER ALL BUT THE SRN ROLLING PLAINS WHERE RECENT CONVECTION IS STILL CYCLING THROUGH VARIOUS STAGES OF DEEP GROWTH. POPS WERE ALSO EXTENDED OVERNIGHT GENERALLY OVER THE NERN 2/3RDS OF THE CWA AS PRECIP SHOULD BE SLOWER TO PROGRESS EASTWARD THAN LAST NIGHT GIVEN THE UPPER RIDGE. .AVIATION... OCCASIONAL MVFR VIS RESTRICTIONS FROM HAZE HAVE RECENTLY IMPROVED AT LBB...HOWEVER HAVE INSERTED A TEMPO 5SM THRU 01Z. PRECIP- WISE...WOULD EXPECT AT LEAST ISO TSRA TO MOVE OUT OF ERN NM LATE THIS EVENING. COVERAGE OF STORMS IS EXPECTED TO BE FAR LESS THAN LAST NIGHT SO WILL KEEP MENTION OUT OF LBB...HOWEVER THERE ARE CREDIBLE INDICATIONS FROM SOME OF THE RAPID UPDATE MODELS THAT A COMPLEX OF STORMS WILL THREATEN CDS BETWEEN 06Z AND 12Z. ADDRESSED THIS SCENARIO WITH A SHORT 3-HOUR WINDOW OF TSRA WHICH WILL BE REFINED AS THE NIGHT WEARS ON. ASIDE FROM TEMPORARY REDUCTIONS IN CIG/VIS IN STORMS...VFR CONDITIONS WILL PREVAIL THROUGH THURSDAY WITH BREEZY S-SELY WINDS. && .PREV DISCUSSION... /ISSUED 352 PM CDT WED JUN 13 2012/ SHORT TERM... BOUNDARY LAYER APPEARS TO BE FAIRLY STABLE OVER THE ROLLING PLAINS THANKS TO OUTFLOW FROM THE STORMS THAT ROLLED ACROSS THIS AREA EARLY THIS MORNING. ACROSS THE SOUTH PLAINS...LATEST VISIBLE SATELLITE SHOWS THAT CU FIELD IS TRYING TO DEVELOP AND DEEPEN. RAP BUFKIT SOUNDINGS CONTINUE TO INDICATE A WEAK CAP THAT IS BROKEN IN A COUPLE OF HOURS AT KLBB WHILE HOLDING THE CAP IN PLACE FURTHER WEST AT CLOVIS. SPC MESOSCALE ANALYSIS ALSO SHOWS THE CAP HOLDING OVER THE ROLLING PLAINS WITH AN UNCAPPED ATMOSPHERE OVER THE SOUTH PLAINS AND MLCAPE VALUES BETWEEN 3500-4000 J/KG. BULK SHEAR VALUES ARE A BIT LOWER THAN YESTERDAY OVER THE ENTIRE AREA BUT 30-40 KNOTS IS IN PLACE ACROSS THE SOUTHWESTERN QUARTER OF THE AREA. THESE FACTORS COULD POTENTIALLY RESULT IN RAPID DEVELOPMENT OF SEVERE STORMS /IF/ THEY ARE ABLE TO DEVELOP. NOT SURE WHAT TO MAKE OF THE POSSIBLE CAP OVER THE SOUTH PLAINS AND WHAT THIS MAY DO FOR OUR CHANCES OF CONVECTION AND ALSO MAKES IT DIFFICULT TO NAIL DOWN THE POP FORECAST FOR TONIGHT. WILL HOLD POPS IN THE LOW END OF CHANCE AS THE TTU/OUN WRF AND THE HRRR HAVE ALL BEEN CONSISTENT IN NOT GENERATING ANY STORMS OVER THE AREA...WITH THE EXCEPTION OF THE HRRR TRYING TO DEVELOP SOME STORMS LATE TONIGHT BETWEEN 03 AND 06Z. ALSO AM CONCERNED THAT THE INCOMING AREA OF ENHANCED CLOUD COVER ON VISIBLE SATELLITE MAY INDICATE SOME KIND OF POCKET OF COOLER AIR ALOFT AND SOME WEAK LIFT THAT MAY HELP STORMS TO FIRE. THE FLAVORS OF THE WRF HAVE SHOWN THAT ACTIVITY IN NORTHEAST NEW MEXICO MAY ORGANIZE INTO ANOTHER COMPLEX THAT COULD MOVE TOWARDS THE NORTHERN ROLLING PLAINS OVERNIGHT AND ONCE AGAIN HAVE KEPT SLIGHT CHANCE POPS ACROSS THIS AREA THROUGH TOMORROW MORNING. FOR THURSDAY...RIDGE AXIS TRIES TO PUSH OVERHEAD WHICH SHOULD HELP SUPPRESS CONVECTION A BIT BUT OPTED TO HOLD SLIGHT CHANCE POPS ACROSS THE WESTERN HALF DEPENDING ON HOW CONVECTION DEVELOPS TONIGHT. MODELS STILL SHOW CONVECTION DEVELOPING ACROSS THE HIGHER TERRAIN OF NM TOMORROW AFTERNOON SO CANNOT RULE OUT AN ISOLATED STORM OR TWO PUSHING TOWARDS THE STATE LINE. TEMPERATURES MAY ALSO BE A FEW DEGREES WARMER WITH THE RIDGE AXIS OVERHEAD BUT LOW-LEVEL MOISTURE MAY HELP TO LIMIT THE WARMUP SOMEWHAT. JORDAN LONG TERM... LATEST WATER VAPOR IMAGERY DISPLAYED A PACIFIC UL DISTURBANCE MOVING ACROSS CALIFORNIA...AND IS PROGGED TO DIG ESE TOWARDS THE DESERT SW TOMORROW NIGHT. THIS WILL PROMOTE SOUTHWESTERLY FLOW ALOFT...AND THUS PERMIT THE DRYLINE TO NEAR THE TEXAS/NEW MEXICO BORDER. FORECAST MODELS HINT AT ADEQUATE CONVERGENCE ALONG THE DRYLINE...SO MUCH SO THAT IT WILL OVERCOME THE LESS THAN 100 J/KG OF CIN. FURTHERMORE...A WEAK EMBEDDED IMPULSE MAY BE ENOUGH TO SPARK CONVECTION ALONG AND EAST OF THE DRYLINE...AS SOUTHEASTERLY SFC WINDS EAST OF THE DRYLINE INDUCE DEWPOINTS IN THE 50S AND 60S. CURRENT THINKING IS THAT THE SAID EMBEDDED IMPULSE WILL EJECT NE ACROSS THE PANHANDLES...HOWEVER WILL MAINTAIN SLIGHT CHANCE POPS ACROSS PORTIONS OF THE CENTRAL AND WESTERN ZONES...WHERE PROGGED SFC-BASED CAPE OF 1.0-1.5 KJ/KG EXISTS. IF STORMS DO INDEED DEVELOP...STRONG TO SEVERE STORMS WILL BE POSSIBLE WITH HAIL AND BRIEF GUSTY WINDS THE PRIMARY THREATS. FRIDAY THROUGH SUNDAY...THE PACIFIC UL DISTURBANCE WILL RETROGRADE WEST ACROSS THE EASTERN PACIFIC...WHILE CONCURRENTLY A PROGRESSIVE PATTERN ACROSS THE NORTHERN U.S. TIER ENSUES...WHICH WILL LEAD TO THE DRYLINE LINGERING ACROSS OR JUST WEST OF THE CWA. DESPITE SLIGHT HEIGHT INCREASES FROM AN UA RIDGE...MOIST LOW LEVELS WILL EXIST AS UPSLOPE SFC WINDS PERSIST /PWATS IN EXCESS OF 1.00 INCH/...AND MODEL SOUNDINGS EXHIBITING STEEPENED LAPSE RATES EACH AFTERNOON/EVENING /SFC-BASED CAPE OF 2.0-2.5 KJ/KG/ SUGGEST THE POTENTIAL FOR STRONG TO SEVERE STORMS MORESO ACROSS THE WESTERN ZONES NEAREST TO THE DRYLINE /HAIL AND GUSTY WINDS THE PRIMARY THREATS/. THE GFS MAINTAINS BEST POPS ACROSS EASTERN NEW MEXICO COINCIDING WITH THE DISPLACEMENT OF THE DRYLINE THROUGHOUT THE SAID PERIOD...WHILE THE NAM AND ECMWF SOLUTIONS ARE A BIT MORE ROBUST /DRYLINE A BIT CLOSER TO THE FA/. AS SUCH...STORMS APPEAR TO BE DEPENDENT ON THE EXACT LOCATION OF THE DRYLINE AND WILL THEREFORE OPT TO KEEP POPS BELOW 30 PERCENT ATTM. MONDAY THROUGH WEDNESDAY THE LONG TERM MODELS DIFFER A BIT IN REGARD TO THE SYNOPTIC PATTERN. THE GFS RETROGRADES THE UA RIDGE TO THE SOUTHWESTERN CONUS BY MONDAY AS AN EASTERN CONUS UA RIDGE PROMOTES AN UA LOW TO MOVE ACROSS SOUTHERN TEXAS AND PERHAPS ALLOW INCREASING CHANCES FOR PRECIP OFF THE CAPROCK TUESDAY-WEDNESDAY. THE ECMWF ON THE OTHER HAND ALSO DEVELOPS AN UA RIDGE ACROSS THE EASTERN CONUS...WHILE A TROPICAL SYSTEM TRANSLATES NORTH ACROSS OLD MEXICO THUS STREAMING LOW TO MID LEVEL MOISTURE ACROSS THE FA...AND A CHANCE FOR STORMS. FURTHERMORE...THE ECMWF HINTS AT THE BROAD UA TROUGH ACROSS THE NORTHERN U.S. TIER TO SURGE A RELATIVELY WEAK DRY COLD FRONT TO ACROSS FAR THE NWRN ZONES TUESDAY BEFORE QUICKLY RETREATING NORTH. WILL NEED TO ANALYZE FUTURE MODEL RUNS FOR CONSENSUS...AND WILL THEREFORE OPT TO MAINTAIN SILENT POPS BEYOND SUNDAY NIGHT ATTM. && .PRELIMINARY POINT TEMPS/POPS... FRIONA 61 93 64 92 62 / 30 20 20 30 30 TULIA 66 91 65 91 65 / 30 20 20 20 20 PLAINVIEW 69 92 67 91 67 / 30 20 20 20 20 LEVELLAND 69 95 67 93 66 / 30 20 20 20 20 LUBBOCK 69 94 69 93 68 / 30 20 20 20 20 DENVER CITY 69 95 68 94 66 / 30 20 20 30 30 BROWNFIELD 70 95 68 93 66 / 30 20 20 20 20 CHILDRESS 68 94 72 93 71 / 30 10 10 10 10 SPUR 70 94 70 93 69 / 20 10 20 20 20 ASPERMONT 73 95 74 95 71 / 20 10 10 10 10 && .LUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 93
AREA FORECAST DISCUSSION...UPDATED
NWS AMARILLO TX
1255 PM CDT TUE JUN 12 2012 .AVIATION... FOR THE 18Z TAFS...THE PRIMARY CONCERN WILL BE THE TIMING OF TSRA ACROSS THE REGION. THOUGH THERE IS A CHANCE FOR STORMS THROUGH THE ENTIRE TAF PERIOD...THE MAIN IMPACT TO THE TERMINALS IS EXPECTED TO BE A 2 TO 4 HOUR PERIOD AS A CONVECTIVE COMPLEX THAT SHOULD DEVELOP IN EASTERN NM/CO MOVES E OR ESE INTO THE PANHANDLES. THIS COMPLEX COULD MOVE INTO THE WESTERN PANHANDLES...INCLUDING KDHT...AS EARLY AS 22 OR 23Z. IT WILL LIKELY NOT AFFECT THE CENTRAL PANHANDLES...INCLUDING KAMA AND KGUY...UNTIL AFTER 00Z. MVFR...OR EVEN IFR VISIBILITIES WITH HEAVY RAIN...VARIABLE AND GUSTY WINDS...AND POSSIBLY SOME HAIL WILL BE POSSIBLE WITH THE STRONGEST STORMS IN THIS COMPLEX. THOUGH ADDITIONAL STORMS BOTH BEFORE AND AFTER THIS PERIOD CAN NOT BE RULED OUT...TOO MUCH UNCERTAINTY TO INCLUDE IN THE TAFS AT THIS TIME. ANOTHER CONCERN WILL BE THE POSSIBILITY OF BR OR LOW CEILINGS DEVELOPING AFTER 06Z...ONCE THE STORMS HAVE PASSED. THE HIGHEST THREAT FOR THIS WILL BE IN KAMA AND KGUY ESPECIALLY IF WINDS REMAIN SOUTHEASTERLY...AND THEY GET ADDITIONAL RAIN. HOWEVER...WINDS MAY ALSO REMAIN TO BREEZY TO SEE MUCH BR DEVELOPMENT. FOR NOW HAVE LEFT OUT OF THE TAFS DUE TO HIGH UNCERTAINTY. JOHNSON && .PREV DISCUSSION... /ISSUED 1216 PM CDT TUE JUN 12 2012/ UPDATE... HAVE UPDATED THE FORECAST TO ADJUST THE POPS A LITTLE FOR THIS AFTERNOON AND THIS EVENING. THE THINKING IS NOW THAT THE BEST CHANCE OF THUNDERSTORMS WILL BE IN THE NORTHWEST BEFORE 00Z AHEAD OF A SHORT WAVE TROUGH EJECTING EAST FROM NORTH CENTRAL NEW MEXICO. THEN THIS ACTIVITY SHOULD SPREAD SOUTHEAST FROM THERE OVERNIGHT INTO THE BETTER MOISTURE AND INSTABILITY AXIS. ALSO ADDED A SEVERE MENTION TO THE STORMS GIVEN THE AMOUNT OF SHEAR AND INSTABILITY. PREV DISCUSSION... /ISSUED 654 AM CDT TUE JUN 12 2012/ AVIATION... FOR THE 12Z TAFS...ONGOING SHOWERS AND TSTMS AT KAMA WILL CONTINUE UNTIL AROUND MID MORNING. MAJORITY OF PRECIPITATION SHOULD BYPASS KDHT AND KGUY THIS MORNING. A LULL IN THE SHOWERS AND TSTMS IS EXPECTED BY EARLY THIS AFTERNOON. NEXT ROUND OF STORMS TO DEVELOP SOMETIME LATE THIS AFTERNOON OR EVENING...DEPENDING ON HOW LONG IT TAKES THE ATMOSPHERE TO RECOVER FROM MORNING TSTMS. FOR THIS REASON... HAVE DECIDED NOT TO INSERT TSTMS AT ANY TAF SITE AFTER THIS MORNING DUE TO LOW CONFIDENCE IN HOW MESOSCALE SITUATION WILL EVOLVE LATER TODAY AND TONIGHT. FUTURE SHIFTS MAY NEED TO CONSIDER ADDING TSTMS TO ONE OR MORE OF THE TAFS IF CONDITIONS BECOME MORE CLEAR CUT. ANDRADE PREV DISCUSSION... /ISSUED 444 AM CDT TUE JUN 12 2012/ DISCUSSION... AN ACTIVE AND WET WX PATTERN IS TAKING SHAPE ACROSS THE AREA AS FIRST ROUND OF SHOWERS AND THUNDERSTORMS ARE CURRENTLY MOVING ACROSS PORTIONS OF THE FA. THESE STORMS WERE BECOMING MORE UPSCALE AS THEY ENCOUNTER A MORE BUOYANT AIR MASS PER LAPS AND RAP DATA INDICATING MUCAPES AROUND 200-600 J/KG. DIVERGENCE PROVIDED BY THE RRQ OF A JET STREAK AND LFQ OF A JET STREAK NOSING INTO THE PANHANDLES ARE ALSO HELPING TO INTENSIFY THESE STORMS. THESE STORMS WILL CONTINUE THROUGH THE NEXT FEW HOURS WHERE 0-6 KM BULK SHEAR AROUND 30-40 KTS AND STEEP MID-LEVEL LAPSE RATES CAN RESULT IN SOME OF THESE STORMS TO BECOME SEVERE. LATER TODAY...EXPECT A BIT OF A LULL IN THUNDERSTORM ACTIVITY ONCE THIS EARLY MORNING CONVECTION EXITS THE AREA. HOWEVER SUFFICIENT LOW- LEVEL MOISTURE WILL BE MAINTAINED ACROSS THE AREA ON BREEZY SOUTHEAST SURFACE WINDS. SEVERAL UPPER-LEVEL DISTURBANCES WILL ALSO TRAVERSE THE SOUTHERN PLAINS TODAY PROVIDING WEAK UPPER LIFT WHILE ANY OUTFLOW BOUNDARIES CAN PROVIDE A FOCUS FOR STORM DEVELOPMENT. FORECAST SOUNDINGS INDICATE THE AIR MASS WILL BE VERY UNSTABLE WITH MLCAPES AROUND 2000-3000 J/KG. SHEAR WILL REMAIN MORE THAN ADEQUATE TO ALLOW SOME STORMS TO BECOME SEVERE AND EXPECT THE MAIN SEVERE THREATS TO BE LARGE HAIL AND STRONG WINDS. CONVECTION WILL BECOME MORE WIDESPREAD TONIGHT AS A LOW-LEVEL JET SETTING UP ACROSS THE SOUTHERN PLAINS WILL HELP TO MAINTAIN AND WARM...MOIST...AND UNSTABLE AIR MASS ACROSS THE AREA. HIGHS TODAY SHOULD BE A LITTLE COOLER...IN THE 80S. ON WEDNESDAY THE SURFACE FLOW WILL TREND MORE TO THE SOUTH AS A COLD FRONT THAT IS CURRENTLY SOUTH OF THE AREA LIFTS NORTH. WEAK MID- LEVEL RIDGING WILL BUILD ACROSS THE SOUTHERN PLAINS HOWEVER SEVERAL UPPER DISTURBANCES WILL QUICKLY BREAK DOWN THE RIDGE. MOIST AND UNSTABLE CONDITIONS WILL REMAIN ACROSS THE AREA SO WILL CONTINUE CHANCE POPS IN THE FORECAST. HAVE ALSO CONTINUED MENTION OF THUNDER IN THE FORECAST THROUGH THE WEEKEND AS THE DRYLINE SHOULD REMAIN WEST OF THE AREA WHILE SOUTHWEST UPPER FLOW TAPS INTO THE TROPICAL MOISTURE OUT OF THE PACIFIC. STILL FAVOR BETTER CHANCES FOR STORMS TO BE IN THE WEST AND CENTRAL SECTIONS OF THE FA GIVEN THE FORECAST POSITION OF THE DRYLINE. THE STRENGTHENING OF A LEE TROUGH AND POSSIBLE EASTWARD MOVEMENT OF THE DRYLINE EARLY NEXT WEEK SHOULD END THUNDER CHANCES WITH THE NEXT POSSIBLE COLD FRONTAL INTRUSION COMING AROUND MID-WEEK. CLK FIRE WEATHER... ABUNDANT ATMOSPHERIC MOISTURE AND CHANCES FOR PRECIPITATION THROUGH MUCH OF THE 7 DAY FORECAST PERIOD WILL PRECLUDE ELEVATED OR CRITICAL FIRE WEATHER CONDITIONS ACROSS THE TX/OK PANHANDLES. CLK && .AMA WATCHES/WARNINGS/ADVISORIES... TX...NONE. OK...NONE. && $$ 16/15
AREA FORECAST DISCUSSION...UPDATED
NWS AMARILLO TX
1216 PM CDT TUE JUN 12 2012 .UPDATE... HAVE UPDATED THE FORECAST TO ADJUST THE POPS A LITTLE FOR THIS AFTERNOON AND THIS EVENING. THE THINKING IS NOW THAT THE BEST CHANCE OF THUNDERSTORMS WILL BE IN THE NORTHWEST BEFORE 00Z AHEAD OF A SHORT WAVE TROUGH EJECTING EAST FROM NORTH CENTRAL NEW MEXICO. THEN THIS ACTIVITY SHOULD SPREAD SOUTHEAST FROM THERE OVERNIGHT INTO THE BETTER MOISTURE AND INSTABILITY AXIS. ALSO ADDED A SEVERE MENTION TO THE STORMS GIVEN THE AMOUNT OF SHEAR AND INSTABILITY. && .PREV DISCUSSION... /ISSUED 654 AM CDT TUE JUN 12 2012/ AVIATION... FOR THE 12Z TAFS...ONGOING SHOWERS AND TSTMS AT KAMA WILL CONTINUE UNTIL AROUND MID MORNING. MAJORITY OF PRECIPITATION SHOULD BYPASS KDHT AND KGUY THIS MORNING. A LULL IN THE SHOWERS AND TSTMS IS EXPECTED BY EARLY THIS AFTERNOON. NEXT ROUND OF STORMS TO DEVELOP SOMETIME LATE THIS AFTERNOON OR EVENING...DEPENDING ON HOW LONG IT TAKES THE ATMOSPHERE TO RECOVER FROM MORNING TSTMS. FOR THIS REASON... HAVE DECIDED NOT TO INSERT TSTMS AT ANY TAF SITE AFTER THIS MORNING DUE TO LOW CONFIDENCE IN HOW MESOSCALE SITUATION WILL EVOLVE LATER TODAY AND TONIGHT. FUTURE SHIFTS MAY NEED TO CONSIDER ADDING TSTMS TO ONE OR MORE OF THE TAFS IF CONDITIONS BECOME MORE CLEAR CUT. ANDRADE PREV DISCUSSION... /ISSUED 444 AM CDT TUE JUN 12 2012/ DISCUSSION... AN ACTIVE AND WET WX PATTERN IS TAKING SHAPE ACROSS THE AREA AS FIRST ROUND OF SHOWERS AND THUNDERSTORMS ARE CURRENTLY MOVING ACROSS PORTIONS OF THE FA. THESE STORMS WERE BECOMING MORE UPSCALE AS THEY ENCOUNTER A MORE BUOYANT AIR MASS PER LAPS AND RAP DATA INDICATING MUCAPES AROUND 200-600 J/KG. DIVERGENCE PROVIDED BY THE RRQ OF A JET STREAK AND LFQ OF A JET STREAK NOSING INTO THE PANHANDLES ARE ALSO HELPING TO INTENSIFY THESE STORMS. THESE STORMS WILL CONTINUE THROUGH THE NEXT FEW HOURS WHERE 0-6 KM BULK SHEAR AROUND 30-40 KTS AND STEEP MID-LEVEL LAPSE RATES CAN RESULT IN SOME OF THESE STORMS TO BECOME SEVERE. LATER TODAY...EXPECT A BIT OF A LULL IN THUNDERSTORM ACTIVITY ONCE THIS EARLY MORNING CONVECTION EXITS THE AREA. HOWEVER SUFFICIENT LOW- LEVEL MOISTURE WILL BE MAINTAINED ACROSS THE AREA ON BREEZY SOUTHEAST SURFACE WINDS. SEVERAL UPPER-LEVEL DISTURBANCES WILL ALSO TRAVERSE THE SOUTHERN PLAINS TODAY PROVIDING WEAK UPPER LIFT WHILE ANY OUTFLOW BOUNDARIES CAN PROVIDE A FOCUS FOR STORM DEVELOPMENT. FORECAST SOUNDINGS INDICATE THE AIR MASS WILL BE VERY UNSTABLE WITH MLCAPES AROUND 2000-3000 J/KG. SHEAR WILL REMAIN MORE THAN ADEQUATE TO ALLOW SOME STORMS TO BECOME SEVERE AND EXPECT THE MAIN SEVERE THREATS TO BE LARGE HAIL AND STRONG WINDS. CONVECTION WILL BECOME MORE WIDESPREAD TONIGHT AS A LOW-LEVEL JET SETTING UP ACROSS THE SOUTHERN PLAINS WILL HELP TO MAINTAIN AND WARM...MOIST...AND UNSTABLE AIR MASS ACROSS THE AREA. HIGHS TODAY SHOULD BE A LITTLE COOLER...IN THE 80S. ON WEDNESDAY THE SURFACE FLOW WILL TREND MORE TO THE SOUTH AS A COLD FRONT THAT IS CURRENTLY SOUTH OF THE AREA LIFTS NORTH. WEAK MID- LEVEL RIDGING WILL BUILD ACROSS THE SOUTHERN PLAINS HOWEVER SEVERAL UPPER DISTURBANCES WILL QUICKLY BREAK DOWN THE RIDGE. MOIST AND UNSTABLE CONDITIONS WILL REMAIN ACROSS THE AREA SO WILL CONTINUE CHANCE POPS IN THE FORECAST. HAVE ALSO CONTINUED MENTION OF THUNDER IN THE FORECAST THROUGH THE WEEKEND AS THE DRYLINE SHOULD REMAIN WEST OF THE AREA WHILE SOUTHWEST UPPER FLOW TAPS INTO THE TROPICAL MOISTURE OUT OF THE PACIFIC. STILL FAVOR BETTER CHANCES FOR STORMS TO BE IN THE WEST AND CENTRAL SECTIONS OF THE FA GIVEN THE FORECAST POSITION OF THE DRYLINE. THE STRENGTHENING OF A LEE TROUGH AND POSSIBLE EASTWARD MOVEMENT OF THE DRYLINE EARLY NEXT WEEK SHOULD END THUNDER CHANCES WITH THE NEXT POSSIBLE COLD FRONTAL INTRUSION COMING AROUND MID-WEEK. CLK FIRE WEATHER... ABUNDANT ATMOSPHERIC MOISTURE AND CHANCES FOR PRECIPITATION THROUGH MUCH OF THE 7 DAY FORECAST PERIOD WILL PRECLUDE ELEVATED OR CRITICAL FIRE WEATHER CONDITIONS ACROSS THE TX/OK PANHANDLES. CLK && .AMA WATCHES/WARNINGS/ADVISORIES... TX...NONE. OK...NONE. && $$ 16/15
AREA FORECAST DISCUSSION...UPDATED
NWS AMARILLO TX
654 AM CDT TUE JUN 12 2012 .AVIATION... FOR THE 12Z TAFS...ONGOING SHOWERS AND TSTMS AT KAMA WILL CONTINUE UNTIL AROUND MID MORNING. MAJORITY OF PRECIPITATION SHOULD BYPASS KDHT AND KGUY THIS MORNING. A LULL IN THE SHOWERS AND TSTMS IS EXPECTED BY EARLY THIS AFTERNOON. NEXT ROUND OF STORMS TO DEVELOP SOMETIME LATE THIS AFTERNOON OR EVENING...DEPENDING ON HOW LONG IT TAKES THE ATMOSPHERE TO RECOVER FROM MORNING TSTMS. FOR THIS REASON... HAVE DECIDED NOT TO INSERT TSTMS AT ANY TAF SITE AFTER THIS MORNING DUE TO LOW CONFIDENCE IN HOW MESOSCALE SITUATION WILL EVOLVE LATER TODAY AND TONIGHT. FUTURE SHIFTS MAY NEED TO CONSIDER ADDING TSTMS TO ONE OR MORE OF THE TAFS IF CONDITIONS BECOME MORE CLEAR CUT. ANDRADE && .PREV DISCUSSION... /ISSUED 444 AM CDT TUE JUN 12 2012/ DISCUSSION... AN ACTIVE AND WET WX PATTERN IS TAKING SHAPE ACROSS THE AREA AS FIRST ROUND OF SHOWERS AND THUNDERSTORMS ARE CURRENTLY MOVING ACROSS PORTIONS OF THE FA. THESE STORMS WERE BECOMING MORE UPSCALE AS THEY ENCOUNTER A MORE BUOYANT AIR MASS PER LAPS AND RAP DATA INDICATING MUCAPES AROUND 200-600 J/KG. DIVERGENCE PROVIDED BY THE RRQ OF A JET STREAK AND LFQ OF A JET STREAK NOSING INTO THE PANHANDLES ARE ALSO HELPING TO INTENSIFY THESE STORMS. THESE STORMS WILL CONTINUE THROUGH THE NEXT FEW HOURS WHERE 0-6 KM BULK SHEAR AROUND 30-40 KTS AND STEEP MID-LEVEL LAPSE RATES CAN RESULT IN SOME OF THESE STORMS TO BECOME SEVERE. LATER TODAY...EXPECT A BIT OF A LULL IN THUNDERSTORM ACTIVITY ONCE THIS EARLY MORNING CONVECTION EXITS THE AREA. HOWEVER SUFFICIENT LOW- LEVEL MOISTURE WILL BE MAINTAINED ACROSS THE AREA ON BREEZY SOUTHEAST SURFACE WINDS. SEVERAL UPPER-LEVEL DISTURBANCES WILL ALSO TRAVERSE THE SOUTHERN PLAINS TODAY PROVIDING WEAK UPPER LIFT WHILE ANY OUTFLOW BOUNDARIES CAN PROVIDE A FOCUS FOR STORM DEVELOPMENT. FORECAST SOUNDINGS INDICATE THE AIR MASS WILL BE VERY UNSTABLE WITH MLCAPES AROUND 2000-3000 J/KG. SHEAR WILL REMAIN MORE THAN ADEQUATE TO ALLOW SOME STORMS TO BECOME SEVERE AND EXPECT THE MAIN SEVERE THREATS TO BE LARGE HAIL AND STRONG WINDS. CONVECTION WILL BECOME MORE WIDESPREAD TONIGHT AS A LOW-LEVEL JET SETTING UP ACROSS THE SOUTHERN PLAINS WILL HELP TO MAINTAIN AND WARM...MOIST...AND UNSTABLE AIR MASS ACROSS THE AREA. HIGHS TODAY SHOULD BE A LITTLE COOLER...IN THE 80S. ON WEDNESDAY THE SURFACE FLOW WILL TREND MORE TO THE SOUTH AS A COLD FRONT THAT IS CURRENTLY SOUTH OF THE AREA LIFTS NORTH. WEAK MID- LEVEL RIDGING WILL BUILD ACROSS THE SOUTHERN PLAINS HOWEVER SEVERAL UPPER DISTURBANCES WILL QUICKLY BREAK DOWN THE RIDGE. MOIST AND UNSTABLE CONDITIONS WILL REMAIN ACROSS THE AREA SO WILL CONTINUE CHANCE POPS IN THE FORECAST. HAVE ALSO CONTINUED MENTION OF THUNDER IN THE FORECAST THROUGH THE WEEKEND AS THE DRYLINE SHOULD REMAIN WEST OF THE AREA WHILE SOUTHWEST UPPER FLOW TAPS INTO THE TROPICAL MOISTURE OUT OF THE PACIFIC. STILL FAVOR BETTER CHANCES FOR STORMS TO BE IN THE WEST AND CENTRAL SECTIONS OF THE FA GIVEN THE FORECAST POSITION OF THE DRYLINE. THE STRENGTHENING OF A LEE TROUGH AND POSSIBLE EASTWARD MOVEMENT OF THE DRYLINE EARLY NEXT WEEK SHOULD END THUNDER CHANCES WITH THE NEXT POSSIBLE COLD FRONTAL INTRUSION COMING AROUND MID-WEEK. CLK FIRE WEATHER... ABUNDANT ATMOSPHERIC MOISTURE AND CHANCES FOR PRECIPITATION THROUGH MUCH OF THE 7 DAY FORECAST PERIOD WILL PRECLUDE ELEVATED OR CRITICAL FIRE WEATHER CONDITIONS ACROSS THE TX/OK PANHANDLES. CLK && .AMA WATCHES/WARNINGS/ADVISORIES... TX...NONE. OK...NONE. && $$
AREA FORECAST DISCUSSION
NWS AMARILLO TX
444 AM CDT TUE JUN 12 2012 .DISCUSSION... AN ACTIVE AND WET WX PATTERN IS TAKING SHAPE ACROSS THE AREA AS FIRST ROUND OF SHOWERS AND THUNDERSTORMS ARE CURRENTLY MOVING ACROSS PORTIONS OF THE FA. THESE STORMS WERE BECOMING MORE UPSCALE AS THEY ENCOUNTER A MORE BUOYANT AIR MASS PER LAPS AND RAP DATA INDICATING MUCAPES AROUND 200-600 J/KG. DIVERGENCE PROVIDED BY THE RRQ OF A JET STREAK AND LFQ OF A JET STREAK NOSING INTO THE PANHANDLES ARE ALSO HELPING TO INTENSIFY THESE STORMS. THESE STORMS WILL CONTINUE THROUGH THE NEXT FEW HOURS WHERE 0-6 KM BULK SHEAR AROUND 30-40 KTS AND STEEP MID-LEVEL LAPSE RATES CAN RESULT IN SOME OF THESE STORMS TO BECOME SEVERE. LATER TODAY...EXPECT A BIT OF A LULL IN THUNDERSTORM ACTIVITY ONCE THIS EARLY MORNING CONVECTION EXITS THE AREA. HOWEVER SUFFICIENT LOW- LEVEL MOISTURE WILL BE MAINTAINED ACROSS THE AREA ON BREEZY SOUTHEAST SURFACE WINDS. SEVERAL UPPER-LEVEL DISTURBANCES WILL ALSO TRAVERSE THE SOUTHERN PLAINS TODAY PROVIDING WEAK UPPER LIFT WHILE ANY OUTFLOW BOUNDARIES CAN PROVIDE A FOCUS FOR STORM DEVELOPMENT. FORECAST SOUNDINGS INDICATE THE AIR MASS WILL BE VERY UNSTABLE WITH MLCAPES AROUND 2000-3000 J/KG. SHEAR WILL REMAIN MORE THAN ADEQUATE TO ALLOW SOME STORMS TO BECOME SEVERE AND EXPECT THE MAIN SEVERE THREATS TO BE LARGE HAIL AND STRONG WINDS. CONVECTION WILL BECOME MORE WIDESPREAD TONIGHT AS A LOW-LEVEL JET SETTING UP ACROSS THE SOUTHERN PLAINS WILL HELP TO MAINTAIN AND WARM...MOIST...AND UNSTABLE AIR MASS ACROSS THE AREA. HIGHS TODAY SHOULD BE A LITTLE COOLER...IN THE 80S. ON WEDNESDAY THE SURFACE FLOW WILL TREND MORE TO THE SOUTH AS A COLD FRONT THAT IS CURRENTLY SOUTH OF THE AREA LIFTS NORTH. WEAK MID- LEVEL RIDGING WILL BUILD ACROSS THE SOUTHERN PLAINS HOWEVER SEVERAL UPPER DISTURBANCES WILL QUICKLY BREAK DOWN THE RIDGE. MOIST AND UNSTABLE CONDITIONS WILL REMAIN ACROSS THE AREA SO WILL CONTINUE CHANCE POPS IN THE FORECAST. HAVE ALSO CONTINUED MENTION OF THUNDER IN THE FORECAST THROUGH THE WEEKEND AS THE DRYLINE SHOULD REMAIN WEST OF THE AREA WHILE SOUTHWEST UPPER FLOW TAPS INTO THE TROPICAL MOISTURE OUT OF THE PACIFIC. STILL FAVOR BETTER CHANCES FOR STORMS TO BE IN THE WEST AND CENTRAL SECTIONS OF THE FA GIVEN THE FORECAST POSITION OF THE DRYLINE. THE STRENGTHENING OF A LEE TROUGH AND POSSIBLE EASTWARD MOVEMENT OF THE DRYLINE EARLY NEXT WEEK SHOULD END THUNDER CHANCES WITH THE NEXT POSSIBLE COLD FRONTAL INTRUSION COMING AROUND MID-WEEK. CLK && .FIRE WEATHER... ABUNDANT ATMOSPHERIC MOISTURE AND CHANCES FOR PRECIPITATION THROUGH MUCH OF THE 7 DAY FORECAST PERIOD WILL PRECLUDE ELEVATED OR CRITICAL FIRE WEATHER CONDITIONS ACROSS THE TX/OK PANHANDLES. CLK && .PRELIMINARY POINT TEMPS/POPS... AMARILLO TX 83 63 87 66 92 / 40 50 30 20 20 BEAVER OK 86 63 93 67 96 / 20 40 30 20 20 BOISE CITY OK 85 62 88 63 94 / 30 40 30 20 20 BORGER TX 86 68 90 68 93 / 30 50 30 20 20 BOYS RANCH TX 85 64 91 65 96 / 40 50 30 20 20 CANYON TX 85 64 88 63 93 / 40 50 30 20 20 CLARENDON TX 84 67 88 67 92 / 40 60 30 20 20 DALHART TX 83 62 89 62 92 / 40 50 30 20 20 GUYMON OK 85 65 91 65 92 / 30 50 30 20 20 HEREFORD TX 83 66 87 61 92 / 40 50 30 20 20 LIPSCOMB TX 85 66 90 69 92 / 20 40 30 20 20 PAMPA TX 83 65 89 65 90 / 30 50 30 20 20 SHAMROCK TX 84 67 87 68 90 / 30 50 30 20 20 WELLINGTON TX 87 69 88 68 92 / 30 50 30 20 20 && .AMA WATCHES/WARNINGS/ADVISORIES... TX...NONE. OK...NONE. && $$ 99/99
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1202 AM CDT TUE JUN 12 2012 .AVIATION... SOME COMPLEXITIES TO THIS MORNINGS FORECAST CENTERED AROUND POTENTIAL FOR CONVECTIVELY INDUCED OUTCOMES. MODEL GUIDANCE HAS BEEN HINTING FOR DAYS AT DEVELOPING A MCS ACROSS THE NORTHERN PART OF OUR FORECAST AREA...MOST LIKELY AFFECTING CHILDRESS. HOWEVER..WHILE SOME DISCRETE ACTIVITY HAS FORMED IN NE NEW MEXICO IT HAS FAILED TO GROW SUBSTANTIALLY UPSCALE. THEREFORE...GIVEN OBSERVATIONS WILL NOT CALL FOR TSRA AT KCDS OVERNIGHT THOUGH THERE IS A LOW PROBABILITY THAT IT WILL OCCUR. GUIDANCE IS LIKELY ALSO INFLUENCED BY PERCEIVED CONVECTIVE THREAT IN DEVELOPING LOW LEVEL MOISTURE AND SOME FOG. BUT...GIVEN 15 DEGREE TDD VALUES AND MID LEVEL CLOUDS...WILL ALSO NOT BITE ON THAT BONE EITHER IN THE OFFICIAL FORECAST. CONFIDENCE IS HIGHER FOR WEDNESDAY AFTERNOON FOR MORE WIDESPREAD CONVECTION WHICH MAY AFFECT BOTH TERMINALS. && .PREV DISCUSSION... /ISSUED 1012 PM CDT MON JUN 11 2012/ UPDATE... CONVECTION SO FAR THIS EVENING HAS REMAINED REMOVED FROM THE CWA. STORMS ASSOCIATED WITH THE FRONTAL BOUNDARY TO OUR SOUTH HAVE SKIRTED AROUND THE SOUTHEAST EDGE OF THE FA THROUGH THE EVENING HOURS UP TO THIS POINT. OUTFLOW FROM EARLIER ACTIVITY WAS IN CLOSE PROXIMITY TO THE SOUTHERN ROLLING PLAINS AND COULD YET BE THE FOCUS FOR STORM DEVELOPMENT THROUGH THE LATE EVENING HOURS. ELSEWHERE...CONVECTION BETWEEN NOW AND MIDNIGHT DOES NOT SEEM AS LIKELY AND HAVE DROPPED POPS GENERALLY TO AOB 20 PERCENT. AFTER MIDNIGHT...INCREASINGLY MOIST/UNSTABLE EASTERLY LOW-LEVEL FLOW...COUPLED WITH FAVORABLE UPPER JET DYNAMICS...AND A WEAK UPPER DISTURBANCE COULD YET BE ENOUGH TO FORCE SOME LATE NIGHT ELEVATED STORMS...IF WARM MID-LEVELS /CIN/ CAN BE OVERCOME. NOT CERTAIN OF THIS SCENARIO...BUT THE 00Z NAM DOES CONTINUE TO ADVERTISE A COMPLEX OF STORMS DEVELOPING ACROSS THE TEXAS PANHANDLE AND ROLLING ACROSS THE NORTHEAST ZONES THROUGH EARLY TUESDAY MORNING. THE 23Z HRRR DOES ALSO INDICATE THAT THE RATHER ISOLATED CONVECTION IN NE NM WILL GROW UPSCALE LATE TONIGHT AND MOVE ACROSS THE NORTHERN ZONES LATE TONIGHT. GIVEN THIS...HAVE MAINTAINED CHANCE POPS OVER ROUGHLY THE NORTHEAST HALF OF THE FA AFTER 06Z. GIVEN MODERATE INSTABILITY AND SUFFICIENT SHEAR...A FEW ELEVATED STRONG TO SEVERE STORMS COULD BE POSSIBLE. UPDATED FORECAST PRODUCTS HAVE BEEN SENT. PREV DISCUSSION... /ISSUED 653 PM CDT MON JUN 11 2012/ AVIATION... VFR CONDITIONS LOOK TO PREVAIL NEXT 24 HOURS WITH PERHAPS A CAVEAT OR TWO. THUNDERSTORM CHANCES LOOK QUITE MEAGER THIS EVENING AND HAVE DROPPED MENTION OF TSRA. MODELS HAVE BEEN HINTING AT AN MCS MOVING OUT OF NEW MEXICO FOR A COUPLE DAYS DURING THE OVERNIGHT HOURS. IF THIS ACTUALLY PLAYS OUT...KCDS LOOKS TO HAVE MOST LIKELY SHOT AT GETTING STORMS BUT CONFIDENCE REMAINS TOO LOW TO INCLUDE ATTM. AS MOIST AIR ADVECTION CONTINUES NEAR KCDS...WE COULD SEE SOME LOW CLOUDS OR PERHAPS EVEN SOME LIGHT FOG DEVELOP THERE TOWARD MORNING. INTO THE AFTERNOON HOURS ON TUESDAY...STORM CHANCES WILL ONCE AGAIN INCREASE. PREV DISCUSSION... /ISSUED 332 PM CDT MON JUN 11 2012/ SHORT TERM... POTENTIALLY WET PATTERN DEVELOPING OVER THE NEXT 36 HOURS. SFC ANALYSIS THIS AFTERNOON SHOWS A COLD FRONT THAT HAS JUST ABOUT STALLED NEAR A HOBBS TO SWEETWATER TO WICHITA FALLS LINE. SOME MOISTURE POOLING IS EVIDENT EITHER SIDE OF THE BOUNDARY. NORTH OF THE FRONT UPSLOPE FLOW DEVELOPING ACROSS ERN NM AS WINDS SLOWLY VEER TOWARD THE EAST. LOOKING AT TWO POTENTIAL AREAS OF THUNDERSTORM DEVELOPMENT LATE THIS AFTERNOON OR EARLY THIS EVENING SHOULD CAPPING INVERSION BE BREACHED...ONE BEING THE VCNTY OF THE COLD FRONT THAT COULD SEE SOME STORMS MOVE INTO THE SERN ZONES AND THE SECOND BEING THE HIGH TERRAIN JUST WEST OF THE FCST AREA WHERE MODESTLY MOIST UPSLOPE FLOW MAY BE ENOUGH TO INITIATE ISO TO SCT THUNDER THERE WITH A POTENTIAL TO MOVE INTO THE WRN ZONES DURING THE EVENING. MOVING INTO THE OVERNIGHT HOURS AND EARLY TUESDAY BEGINS TO BREED MIXED SIGNALS AS THE 12Z NAM AND THE 12Z TTU-WRF BOTH DEVELOP THUNDERSTORMS ACROSS THE SRN PANHANDLE. GFS NOT SHOWING SIMILAR QPF BUT IS SHOWING SIMILAR SUPPORT ONCE BEGIN TO LOOK AT MID LEVELS. MODELS ARE PRETTY CONSISTING SHOWING MID LEVEL MOISTENING AS LARGE MOISTURE PLUME EVIDENT ON WATER VAPOR IMAGERY SPREADS ACROSS THE REGION. PROGGED SOUNDINGS SHOWING ABOUT 1500 J/KG OF CAPE LATE TONIGHT WHEN LIFTING FROM ABOUT 750 MB BUT ALSO SHOWING ABOUT 100 J/KG OF CIN. HOWEVER...LIFT FROM MODEST MID LEVEL MOIST ISENTROPIC MECHANISM AND PAIR OF JET STREAKS /ONE ACROSS CNTL PLAINS AND THE OTHER ACROSS THE SRN ROCKIES/ MAY BE ENOUGH TO OVERCOME THE NEGATIVE ENERGY WITH SCATTERED TSRA LOOKING POSSIBLE. WILL GO AHEAD AND FOCUS ON THAT AREA WITH HIGHER CHANCE POPS AFTER 06Z WHILE PRE-06Z PERIOD WILL FOCUS ON THE AFOREMENTIONED WRN AND SERN AREAS. WHETHER THE SRN PANHANDLE CONVECTION CAN DEVELOP LATE TONIGHT AND THEN BE SUSTAINED INTO THE 12Z-18Z PERIOD AS THE NAM SUGGEST WILL BE KEY IN CONVECTIVE FCST FOR TUESDAY AFTN. OBVIOUSLY WIDESPREAD CONVECTION DURING THE MORNING HOURS WOULD INITIALLY WEAKEN CHANCES FOR PRECIP DURING PEAK CONVECTIVE HOURS TUESDAY AFTN ACROSS THE ROLLING PLAINS. HOWEVER...FOCUS FOR INITIATION LOOKS LIKE IT MAY BE FARTHER WEST IN A ZONE OF GENERALLY NW-SE ORIENTED MOISTURE ADVECTION AS THE COLD FRONT LIFTS NWD TUESDAY AFTN. FCST HIGH TEMPERATURES WILL BE COOLER...GENERALLY IN THE 80S...BUT RICH LOW LEVEL MOISTURE SHOULD STILL MAKE FOR MLCAPE IN EXCESS OF 1500 J/KG IN MUCH OF THE FCST AREA AND POSSIBLY APPROACHING 2500-PLUS IN A BAND NEAR THE RETREATING FRONT. WILL CONTINUE WITH CHC POPS FOR NOW RUNNING THE HIGHEST CHANCE ACROSS ROUGHLY THE WRN HALF OF THE AREA WITH UNDERSTANDING THAT A RELATIVE MINIMUM ACROSS THE EAST MAY NOT WORK OUT IF AFOREMENTIONED OVERNIGHT CONVECTION DOES NOT MATERIALIZE. WILL THEN CONTINUE WITH HIGH CHANCE POPS TUESDAY AS CONVECTION SPREADS EWD DURING THE EVENING AND THEN POTENTIAL FOR AN MCS INTO THE NRN ZONES LATE IN THE NIGHT ROLLING IN FROM THE NW. LONG TERM... BY WEDNESDAY THE FRONTAL SYSTEM IS EXPECTED TO LIFT NORTHWARD AND AREA RAIN CHANCES SHOULD BEGIN TO DECREASE. UPPER LEVEL MOISTURE STREAMING OUT OF THE PACIFIC ACROSS MEXICO INTO THE AREA IS ONE POSITIVE FACTOR. THE DRYLINE SHOULD REMAIN TO OUR WEST OVER NEW MEXICO FOR MOST OF THE REMAINDER OF THE WEEK THROUGH NEXT WEEKEND. THE SLIGHT CHANCE OF THUNDERSTORMS WHICH REMAINS IN THE FORECAST THROUGH NEXT WEEKEND IS MOSTLY TIED TO DRYLINE ACTIVITY BEING PUSHED EASTWARD WITH WESTERLY WINDS ALOFT IN THE LATE AFTERNOON AND EVENING HOURS. BEST RAIN CHANCES WILL BE OVER OUR WESTERN COUNTIES. && .PRELIMINARY POINT TEMPS/POPS... FRIONA 60 81 63 87 64 / 20 40 40 30 30 TULIA 62 80 64 87 64 / 40 40 50 30 20 PLAINVIEW 63 80 65 88 65 / 30 40 40 30 20 LEVELLAND 64 86 65 91 67 / 20 40 50 30 20 LUBBOCK 65 84 66 90 68 / 30 40 50 30 20 DENVER CITY 65 91 65 92 68 / 20 40 40 30 30 BROWNFIELD 66 90 68 91 68 / 20 40 50 30 20 CHILDRESS 66 85 67 88 68 / 40 50 50 20 20 SPUR 68 85 68 90 68 / 30 40 50 20 20 ASPERMONT 70 89 70 92 71 / 30 40 50 20 20 && .LUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 99/99/26
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
631 PM CDT WED JUN 13 2012 .SHORT TERM...TONIGHT THROUGH FRIDAY NIGHT 356 PM CDT WED JUN 13 2012 AT 3 PM...A CONVECTIVELY INDUCED VORTICITY MAXIMUM WAS MOVING THROUGH NORTH-CENTRAL IOWA AND SOUTH-CENTRAL MINNESOTA. THE LAPS INDICATES MODERATE TO STRONG 800-600 MB FRONTOGENESIS ACROSS SOUTHEAST MINNESOTA AND NORTHEAST IOWA. THE LATEST RAP CONTINUES TO SHOW THAT THIS FRONTOGENESIS WILL CONTINUE TO WEAKEN LATE THIS AFTERNOON. AS THIS OCCURS...EXPECT THE BAND OF SHOWERS JUST TO OUR WEST WILL CONTINUE TO WEAKEN AND DISSIPATE. THIS IS IN GOOD AGREEMENT WITH THE HRRR...EAST ARW...AND EAST NMM. FOR TONIGHT...THE 13.12Z MODELS ARE IN GOOD AGREEMENT THAT STRONG 925 TO 700 MB MOISTURE TRANSPORT WILL DEVELOP ACROSS NORTHERN AND WESTERN MINNESOTA. THIS IS IN RESPONSE TO A WARM FRONT MOVING THROUGH THIS REGION. ALL OF THE MESO MODELS AND BROADER SCALE MODELS ARE IN FAIRLY GOOD AGREEMENT THAT A MAJORITY OF THE PRECIPITATION OVERNIGHT WILL BE WEST OF A CHARLES CITY IOWA TO DIAMOND LAKE WISCONSIN LINE. ON THURSDAY AFTERNOON AND EVENING...THE MODELS ARE SHOWING THAT THERE WILL INCREASING SHEAR ACROSS EASTERN MINNESOTA...AND NORTHERN WESTERN WISCONSIN AS A STRONG WAVE SHORT WAVE MOVES ACROSS NORTHERN MINNESOTA. BULK SHEARS CLIMB ABOVE 40 KNOTS ACROSS THE AFOREMENTIONED AREAS WHICH WILL MAKE IT FAVORABLE FOR THE DEVELOPMENT OF SUPERCELL THUNDERSTORMS. THE SIGNIFICANT TORNADO PARAMETER SUGGESTS THAT THERE WILL BE THE POTENTIAL OF TORNADOES. THE NAM/WRF WOULD SUGGEST EAST-CENTRAL MINNESOTA AND NORTHWEST WISCONSIN. MEANWHILE THE GFS INDICATES THAT THIS MAY BE A BIT FURTHER SOUTH AND IT WOULD INCLUDE SOUTHEAST MINNESOTA AND WEST- CENTRAL WISCONSIN. WHILE THE SHEAR IS GOOD...THERE IS SOME CONCERN THAT THAT DEW POINTS IN THE MODELS MAY BE A BIT TOO HIGH...AND IF THIS IS TRUE THAN THE CAPES MAY BE TOO HIGH TOO. THE TORNADO THREAT WOULD LIKELY IN THE MID TO LATE AFTERNOON...AND THEN EVOLVE INTO A WIND THREAT AS THE COLD POOLS COALESCE. BEYOND THIS TIME PERIOD...THERE IS A LOT OF UNCERTAINTY ON WHERE THE FRONT WILL BE LOCATED ACROSS THE REGION. DUE TO THIS...THERE IS LOW CONFIDENCE ON BOTH THE TEMPERATURE AND PRECIPITATION FORECAST. .LONG TERM...SATURDAY THROUGH WEDNESDAY 356 PM CDT WED JUN 13 2012 ON SATURDAY AND SATURDAY NIGHT...THE MODELS SUGGEST THAT A COLD FRONT AND UPPER LEVEL TROUGH WILL BE MOVING THROUGH THE REGION. THE BULK SHEAR WILL ONCE AGAIN CLIMB ABOVE 40 KNOTS. THIS WOULD BE CONDUCIVE FOR THE DEVELOPMENT OF SUPERCELL THUNDERSTORMS. HOWEVER THERE IS QUITE A BIT OF UNCERTAINTY ON WHEN THE COLD FRONT WILL MOVE THROUGH THE REGION AND HOW MUCH INSTABILITY WILL BE AHEAD OF IT. ON SUNDAY AND SUNDAY NIGHT...BOTH THE GEM AND ECMWF INDICATE THAT THE AREA MAY BE DRY AS HIGH PRESSURE BUILDS ACROSS THE REGION. MEANWHILE THE GFS IS SHOWING YET ANOTHER FRONT MOVING INTO THE REGION. DUE TO THIS THE ALL BLEND POPS WERE REDUCED SOME. LOOKING TOWARD THE MIDDLE OF NEXT WEEK...THERE LOOKS TO BE A PATTERN CHANGE BACK TO NORTHWEST FLOW AS A TROUGH BUILDS ACROSS THE REGION. THE GFS IS NOT AS AGGRESSIVE AS THE ECMWF. HOWEVER LOOKING WITH A MADDEN JULIAN OSCILLATION MOVING FROM PHASE 6 TO 7...THE ECMWF WOULD BE THE MOST PROBABLE OUTCOME. && .AVIATION...TONIGHT AND THURSDAY 631 PM CDT WED JUN 13 2012 WEAK SHORTWAVE HAS RESULTED IN SOME LIGHT SHOWERS OVER MINNESOTA...BUT THESE WERE QUICKLY DISSIPATING AS THE MOVED EAST DUE TO THE DRY LOW LEVEL AIR IN PLACE. VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD. MAIN ATTENTION THEN TURNS TO THURSDAY AFTERNOON AND THE CONVECTIVE POTENTIAL. MOISTURE TRANSPORT DOES INCREASE SOMEWHAT...ESPECIALLY INTO SOUTHEAST MINNESOTA LATE IN THE DAY. DID MENTION VCTS AT KRST AFTER 20Z FOR THIS POTENTIAL...BUT KEPT KLSE DRY. && .ARX WATCHES/WARNINGS/ADVISORIES... 356 PM CDT WED JUN 13 2012 WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...BOYNE LONG TERM...BOYNE AVIATION...RABERDING
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1034 AM CDT TUE JUN 12 2012 .UPDATE...SCATTERED TO BROKEN CUMULUS IS EXPECTED THROUGH THE AFTERNOON. MAY BE A BIT CLOUDIER NORTH OF MADISON THAN PREVIOUSLY EXPECTED...BUT OTHERWISE THE FORECAST IS ON TRACK. A GREAT AFTEROON AHEAD WITH HIGHS IN THE UPPER 60S TO LOW 70S. && .AVIATION/18Z TAFS/...STRATOCUMULUS FIELD IS CURRENTLY PUSHING IN FROM THE NORTHWEST UNDER COOLER AIR ALOFT. CIGS MAY BREIFLY DROP TO MVFR THROUGH LATE MORNING...BUT OVERALL EXPECTING INCREASING MIXING TO RAISE CEILINGS TO VFR. OTHERWISE...FAIR WEATHER EXPECTED THROUGH WEDNESDAY. && .PREV DISCUSSION... /ISSUED 341 AM CDT TUE JUN 12 2012/ SHORT TERM... TODAY AND TONIGHT...FORECAST CONFIDENCE MEDIUM TO HIGH. MAIN ISSUES TODAY ARE AMOUNT OF CLOUD COVER AND TEMPERATURES. CURRENT IR AND FOG PRODUCT SATELLITE IMAGERY INDICATING MOST OF THE STRATOCU ASSOCIATED WITH THE COLD AIR ADVECTION WILL REMAIN CLOSE TO SHORT WAVE TROUGH ACROSS NORTHERN WISCONSIN...BUT THERE IS A POCKET OF SC FARTHER SOUTH IN CENTRAL MN AHEAD OF WEAK VORT MAX ON WATER VAPOR LOOPS THAT WILL HAVE TO BE WATCHED...AS NAM AND RAP 925-850MB RH FORECASTS INDICATE 60 PCT OR MORE CROSSING THE REGION THIS MORNING INTO THIS AFTERNOON AND BOTH HAVE ENOUGH MOISTURE...THOUGH SHALLOW...AROUND 4-5K FT ON MODEL SOUNDINGS FOR A BROKEN DECK. HOWEVER...SFC DEW POINTS ON THOSE SOUNDINGS APPEAR A BIT HIGH...SO WILL HOLD SKY COVER IN THE 40 PCT RANGE ACROSS THE NORTHERN CWA HAVE PARTLY CLOUDY 850 MB AND 925 MB TEMPERATURES VERY SIMILAR ON ALL MODELS...THOUGH 00Z ECMWF 925 MB TEMPS ABOUT 2C TO 4C WARMER. WILL TREND TOWARD THE COOLER BLENDED TEMPS FOR HIGHS IN THE UPPER 60S NORTH AND LOWER 70S SOUTH. CLEAR SKIES AND LIGHT WINDS TONIGHT AS SURFACE HIGH CROSSES STATE WILL ALLOW GOOD RADIATIONAL COOLING CONDITIONS...WITH LOWS IN THE 40S EXPECTED EXCEPT NEAR THE LAKE AND THE FAR SOUTHEAST. FORCING AHEAD OF NEXT WAVE REMAINS WEST THROUGH 12Z WEDNESDAY...WITH ONLY THE LEADING EDGE OF MID TO HIGH LEVEL WARM AIR ADVECTION CLOUDS REACHING THE WESTERN CWA BY MORNING. THE COOL OVERNIGHT LOWS WILL PRODUCE SOME PATCHY FOG IN THE WI RIVER VALLEY. WEDNESDAY THROUGH THURSDAY...FORECAST CONFIDENCE HIGH. HIGH PRESSURE WILL DRIFT ACROSS THE GREAT LAKES REGION THROUGH THURSDAY. EASTERLY FLOW WILL KEEP LAKESHORE AREAS COOLER THAN INLAND AREAS. 925MB TEMPS WILL STEADILY INCREASE...UP TO AROUND 20C IN SOUTH CENTRAL WI BY THU AFTERNOON...YIELDING MAX TEMPS AROUND 80. DEWPOINT TEMPS SEEM CHARACTERISTICALLY OVERDONE BY THE MODELS GIVEN THAT THERE IS LIMITED MOISTURE RETURN WITH THE WAA...SO WENT WITH THE BIAS-CORRECTED LOWER VALUES GENERALLY IN THE 40S. A 500MB SHORTWAVE IS EXPECTED TO MOVE ACROSS SOUTHERN/CENTRAL WI WED NIGHT WHICH SHOULD LEAD TO MID CLOUDS OVERHEAD. TOO DRY AND NOT ENOUGH DEEP LEVEL FORCING FOR ANY PRECIP. LONG TERM... FRIDAY THROUGH TUESDAY...FORECAST CONFIDENCE MEDIUM TO HIGH. THE UPPER LEVEL PATTERN IN THE EXTENDED RANGE FORECAST SHOWS A REX BLOCK RETROGRADING INTO THE CENTER OF THE COUNTRY. HIGH PRESSURE RIDGING WILL LIKELY KEEP SOUTHEAST WI ON THE DRY SIDE OF A STATIONARY FRONTAL BOUNDARY SETTING UP ACROSS CENTRAL/NORTHERN WI. SEVERAL SHORTWAVES WILL TRACK ALONG THE FRONT DURING THIS PERIOD...LEADING TO THE SMALL CHANCES FOR THUNDERSTORMS MENTIONED IN MAINLY SOUTH CENTRAL WI. THE ECMWF LOOKS A LITTLE TOO PROGRESSIVE WITH BREAKING DOWN THE RIDGE AND DROPPING THE FRONT THROUGH SOUTHERN WI ALREADY ON TUE. THE NWS HYDROMETEOROLOGICAL PREDICTION CENTER /HPC/ FAVORS THE SLOWER SOLUTION OF THE 00Z GFS AND 00Z ECMWF ENSEMBLE MEAN MODEL BLEND. THIS WOULD KEEP SOUTHERN WI GENERALLY DRY THROUGH TUESDAY. TEMPS WILL WARM BACK INTO THE MID 80S TO LOWER 90S INLAND FROM LAKE MICHIGAN WITH PERSISTENT SOUTHERLY FLOW THROUGH MONDAY AND LIKELY BEYOND. AVIATION/12Z TAFS/... LOOKING AT VFR CONDITIONS THROUGH THE FORECAST. MORNING MIXING WILL BRING MORE CONSISTENT WIND GUSTS IN THE 15 TO 20 KNOT RANGE...EASING THROUGH THE LATE AFTERNOON AND EVENING AS HIGH PRESSURE SLIDES OVER STATE. EXPECTING MAINLY SCATTERED STRATOCUMULUS TODAY...THOUGH BASED ON SATELLITE IMAGERY THERE IS A CHANCE FOR A BROKEN 4-5K FT DECK TO PASS MAINLY JUST NORTH OF THE TAF SITES THAT WILL HAVE TO BE MONITORED UP TO ISSUANCE TIME. CLEAR SKIES AND LIGHT WINDS TONIGHT MAY BRING SOME PATCHY GROUND FOG...BUT POTENTIAL TOO LOW TO MENTION. BEST CHANCE FOR VSBY REDUCING FOG WILL BE IN THE WI RIVER VALLEY TONIGHT. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...NONE. && $$ UPDATE...DDV TODAY/TONIGHT AND AVIATION/MARINE...REM WEDNESDAY THROUGH MONDAY...MRC
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
341 AM CDT TUE JUN 12 2012 .SHORT TERM... TODAY AND TONIGHT...FORECAST CONFIDENCE MEDIUM TO HIGH. MAIN ISSUES TODAY ARE AMOUNT OF CLOUD COVER AND TEMPERATURES. CURRENT IR AND FOG PRODUCT SATELLITE IMAGERY INDICATING MOST OF THE STRATOCU ASSOCIATED WITH THE COLD AIR ADVECTION WILL REMAIN CLOSE TO SHORT WAVE TROUGH ACROSS NORTHERN WISCONSIN...BUT THERE IS A POCKET OF SC FARTHER SOUTH IN CENTRAL MN AHEAD OF WEAK VORT MAX ON WATER VAPOR LOOPS THAT WILL HAVE TO BE WATCHED...AS NAM AND RAP 925-850MB RH FORECASTS INDICATE 60 PCT OR MORE CROSSING THE REGION THIS MORNING INTO THIS AFTERNOON AND BOTH HAVE ENOUGH MOISTURE...THOUGH SHALLOW...AROUND 4-5K FT ON MODEL SOUNDINGS FOR A BROKEN DECK. HOWEVER...SFC DEW POINTS ON THOSE SOUNDINGS APPEAR A BIT HIGH...SO WILL HOLD SKY COVER IN THE 40 PCT RANGE ACROSS THE NORTHERN CWA HAVE PARTLY CLOUDY 850 MB AND 925 MB TEMPERATURES VERY SIMILAR ON ALL MODELS...THOUGH 00Z ECMWF 925 MB TEMPS ABOUT 2C TO 4C WARMER. WILL TREND TOWARD THE COOLER BLENDED TEMPS FOR HIGHS IN THE UPPER 60S NORTH AND LOWER 70S SOUTH. CLEAR SKIES AND LIGHT WINDS TONIGHT AS SURFACE HIGH CROSSES STATE WILL ALLOW GOOD RADIATIONAL COOLING CONDITIONS...WITH LOWS IN THE 40S EXPECTED EXCEPT NEAR THE LAKE AND THE FAR SOUTHEAST. FORCING AHEAD OF NEXT WAVE REMAINS WEST THROUGH 12Z WEDNESDAY...WITH ONLY THE LEADING EDGE OF MID TO HIGH LEVEL WARM AIR ADVECTION CLOUDS REACHING THE WESTERN CWA BY MORNING. THE COOL OVERNIGHT LOWS WILL PRODUCE SOME PATCHY FOG IN THE WI RIVER VALLEY. WEDNESDAY THROUGH THURSDAY...FORECAST CONFIDENCE HIGH. HIGH PRESSURE WILL DRIFT ACROSS THE GREAT LAKES REGION THROUGH THURSDAY. EASTERLY FLOW WILL KEEP LAKESHORE AREAS COOLER THAN INLAND AREAS. 925MB TEMPS WILL STEADILY INCREASE...UP TO AROUND 20C IN SOUTH CENTRAL WI BY THU AFTERNOON...YIELDING MAX TEMPS AROUND 80. DEWPOINT TEMPS SEEM CHARACTERISTICALLY OVERDONE BY THE MODELS GIVEN THAT THERE IS LIMITED MOISTURE RETURN WITH THE WAA...SO WENT WITH THE BIAS-CORRECTED LOWER VALUES GENERALLY IN THE 40S. A 500MB SHORTWAVE IS EXPECTED TO MOVE ACROSS SOUTHERN/CENTRAL WI WED NIGHT WHICH SHOULD LEAD TO MID CLOUDS OVERHEAD. TOO DRY AND NOT ENOUGH DEEP LEVEL FORCING FOR ANY PRECIP. .LONG TERM... FRIDAY THROUGH TUESDAY...FORECAST CONFIDENCE MEDIUM TO HIGH. THE UPPER LEVEL PATTERN IN THE EXTENDED RANGE FORECAST SHOWS A REX BLOCK RETROGRADING INTO THE CENTER OF THE COUNTRY. HIGH PRESSURE RIDGING WILL LIKELY KEEP SOUTHEAST WI ON THE DRY SIDE OF A STATIONARY FRONTAL BOUNDARY SETTING UP ACROSS CENTRAL/NORTHERN WI. SEVERAL SHORTWAVES WILL TRACK ALONG THE FRONT DURING THIS PERIOD...LEADING TO THE SMALL CHANCES FOR THUNDERSTORMS MENTIONED IN MAINLY SOUTH CENTRAL WI. THE ECMWF LOOKS A LITTLE TOO PROGRESSIVE WITH BREAKING DOWN THE RIDGE AND DROPPING THE FRONT THROUGH SOUTHERN WI ALREADY ON TUE. THE NWS HYDROMETEOROLOGICAL PREDICTION CENTER /HPC/ FAVORS THE SLOWER SOLUTION OF THE 00Z GFS AND 00Z ECMWF ENSEMBLE MEAN MODEL BLEND. THIS WOULD KEEP SOUTHERN WI GENERALLY DRY THROUGH TUESDAY. TEMPS WILL WARM BACK INTO THE MID 80S TO LOWER 90S INLAND FROM LAKE MICHIGAN WITH PERSISTENT SOUTHERLY FLOW THROUGH MONDAY AND LIKELY BEYOND. && .AVIATION/12Z TAFS/... LOOKING AT VFR CONDITIONS THROUGH THE FORECAST. MORNING MIXING WILL BRING MORE CONSISTENT WIND GUSTS IN THE 15 TO 20 KNOT RANGE...EASING THROUGH THE LATE AFTERNOON AND EVENING AS HIGH PRESSURE SLIDES OVER STATE. EXPECTING MAINLY SCATTERED STRATOCUMULUS TODAY...THOUGH BASED ON SATELLITE IMAGERY THERE IS A CHANCE FOR A BROKEN 4-5K FT DECK TO PASS MAINLY JUST NORTH OF THE TAF SITES THAT WILL HAVE TO BE MONITORED UP TO ISSUANCE TIME. CLEAR SKIES AND LIGHT WINDS TONIGHT MAY BRING SOME PATCHY GROUND FOG...BUT POTENTIAL TOO LOW TO MENTION. BEST CHANCE FOR VSBY REDUCING FOG WILL BE IN THE WI RIVER VALLEY TONIGHT. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...NONE. && $$ TODAY/TONIGHT AND AVIATION/MARINE...REM WEDNESDAY THROUGH MONDAY...MRC
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1113 PM CDT MON JUN 11 2012 .SHORT TERM...THROUGH WEDNESDAY NIGHT 253 PM CDT MON JUN 11 2012 MAIN FORECAST CONCERN IS WITH THE TEMPERATURES THROUGH TUESDAY AND RAIN CHANCES FOR WEDNESDAY NIGHT. SURFACE ANALYSIS THIS AFTERNOON SHOWS A WIND SHIFT/DRY LINE EXTENDING FROM NORTH CENTRAL WISCONSIN THROUGH THE FORECAST AREA INTO NORTHWEST MISSOURI. LOCAL RADAR SHOWS A FEW SHOWERS DEVELOPING ALONG THIS BOUNDARY. THE HRRR HAS BEEN CONSISTENTLY SHOWING THE SHOWERS FORMING OVER THE AREA THIS AFTERNOON. THE 11.15Z RUN CONTINUES THIS TREND SHOWING THEM MOVING TO THE EAST THROUGH THE REMAINDER OF THE AFTERNOON WITH THE BOUNDARY. THE SHOWERS AND BOUNDARY ARE EXPECTED TO BE EAST OF THE FORECAST AREA BY 00Z...SO NO PLANS TO CARRY ANY EVENING RAIN CHANCES. AFTER THAT...IT IS A QUESTION OF HOW MUCH COOL AIR SETTLES IN OVER THE AREA AS HIGH PRESSURE BUILDS IN. BOTH THE 11.12Z NAM AND GFS INDICATE 925 MB TEMPERATURES SHOULD DIP DOWN TO 5-7C TONIGHT BEFORE STARTING TO REBOUND TO AROUND 10C TUESDAY NIGHT. SURFACE TEMPERATURES WILL GENERALLY FALL TO AROUND 50 TONIGHT AS A NORTHWEST BREEZE IS EXPECTED TO CREATE JUST ENOUGH MIXING TO KEEP THEM FROM GOING ANY LOWER. HIGHS TUESDAY WILL BE MUCH COOLER TOPPING OUT IN THE UPPER 60S TO LOWER 70S. THE COOLEST NIGHT WILL BE TUESDAY NIGHT DESPITE THE SLIGHTLY WARMER 925 MB TEMPERATURES. THE SURFACE HIGH WILL BE RIGHT OVER THE AREA ALLOWING THE WINDS TO DECOUPLE AND EXCELLENT RADIATIONAL COOLING TO OCCUR. EXPECTING LOWS TO BE IN THE 40S WITH THE FAVORED COOLER SPOTS DIPPING INTO THE UPPER 30S. AS THE SURFACE HIGH THEN MOVES OFF TO THE EAST...THE CONCERN BECOMES WHETHER THERE WILL BE ANY SHOWERS THAT DEVELOP IN THE RETURN FLOW. THE MODELS SUGGEST THERE WILL BE A SHORT WAVE TROUGH MOVING ACROSS THE DAKOTAS WEDNESDAY NIGHT WITH THE BEST PV ADVECTION IN THE 500-300MB LAYER STAYING NORTHWEST OF THE AREA. THE BEST LOW LEVEL MOISTURE TRANSPORT WILL BE INTO THIS WAVE...BUT THERE WILL ALSO BE A WEAKER BRANCH SPLITTING OFF TO THE NORTHEAST AHEAD OF ANOTHER SHORT WAVE TROUGH. THIS PLACES THE WESTERN SECTIONS OF THE FORECAST UNDER UNDER THE EASTERN CONVERGENT SIDE OF THE MOISTURE TRANSPORT AXIS. THIS IS EXPECTED TO COINCIDE WITH 1-2 UBAR/S OF UP GLIDE ON THE 310K ISENTROPIC SURFACE AND WHILE THE FORCING IS NOT THAT STRONG FELT THERE WAS ENOUGH TO JUSTIFY A 20 PERCENT RAIN CHANCES LATE TUESDAY NIGHT OVER THE NORTHWEST SECTIONS OF THE AREA. .LONG TERM...THURSDAY THROUGH MONDAY 253 PM CDT MON JUN 11 2012 CONSIDERABLE UNCERTAINTY IN THE EXTENDED PART OF THE FORECAST. THE UPPER LEVEL RIDGE IS EXPECTED TO BUILD FROM THE SOUTHERN PLAINS INTO SOUTHEAST CANADA. MODELS HAVE BEEN SHOWING RUN TO RUN DIFFERENCES ON HOW FAR WEST THE RIDGE WILL EXTEND AND WHETHER THIS WILL ALLOW ANY SHORT WAVE TROUGHS IN THE SOUTHWEST FLOW TO IMPACT THE AREA. THE 11.12Z ECMWF HAS COME IN WITH AN EVEN FLATTER AND FARTHER EAST RIDGE AXIS WHICH ALLOWS A SYSTEM TO MOVE ACROSS THE UPPER MIDWEST FOR THE WEEKEND. THE GFS AND 11.12Z GEM ARE MORE ROBUST WITH THE RIDGE AXIS WHICH DEFLECTS THIS SYSTEM OFF TO THE NORTHWEST. MODELS ARE KNOWN TO STRUGGLE MIGHTILY WITH SOUTHWEST FLOW SO HAVE OPTED TO LEAVE IN THE SMALL RAIN CHANCES AS CONFIDENCE TO PULL THEM OUT IS JUST NOT THERE. && .AVIATION...THROUGH 06Z WEDNESDAY 1113 PM CDT MON JUN 11 2012 CLEAR SKIES WILL PERSIST OVERNIGHT WITH A WEAK VFR FAIR WEATHER CUMULUS FIELD DEVELOPING LATE TUESDAY MORNING INTO THE AFTERNOON. WINDS WILL BE THE MAIN FOCUS THROUGH TUESDAY WITH THE PRESSURE GRADIENT GRADUALLY WEAKENING INTO THE AFTERNOON. GUSTS HAVE STAYED UP AROUND 20KTS AT LSE WHERE SOME CHANNELING OF THE WIND MAY BE OCCURRING OUT OF THE WEST-NORTHWEST. MEANWHILE...THE GUSTS HAVE SUBSIDED AT RST...BUT THERE HAVE BEEN OTHER OBSERVATIONS ACROSS SOUTH CENTRAL MINNESOTA THAT ARE STILL GUSTING...SO AM NOT SOLD THAT THEIR WINDS WILL STAY DOWN OVERNIGHT. THESE WINDS WILL WEAKEN TUESDAY AFTERNOON AS A RIDGE OF HIGH PRESSURE MOVES INTO THE REGION. THERE IS THE POSSIBILITY OF SOME RIVER VALLEY FOG WEDNESDAY MORNING DUE TO THE COLD SURFACE AIR SITTING OVER THE WARM MISSISSIPPI RIVER...BUT ANY VISIBILITY REDUCTIONS WOULD COME SOMETIME AFTER 6Z...IF AT ALL. && .ARX WATCHES/WARNINGS/ADVISORIES... 253 PM CDT MON JUN 11 2012 WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...04 LONG TERM...04 AVIATION...HALBACH
AREA FORECAST DISCUSSION
NWS MIAMI FL
357 AM EDT THU JUN 14 2012 .DISCUSSION...AFTER SOME LATE EVENING CONVECTION OVER PALM BEACH AND BROWARD COUNTIES, WHICH DIMINISHED AROUND 04Z, SKIES HAVE BECOME MOSTLY CLEAR TO PARTLY CLOUDY ACROSS THE REGION. A BIT OF PATCHY FOG COULD DEVELOP IN A FEW AREAS ACROSS THE INTERIOR AND LAKE REGION EARLY THIS MORNING, BUT POTENTIAL IS LOW. OTHERWISE, THE DAY WILL BEGIN TRANQUIL AND WARM ACROSS MUCH OF THE REGION. A MID LEVEL TROUGH AXIS AND ASSOCIATED SURFACE FRONTAL BOUNDARY WILL MOVE INTO CENTRAL FLORIDA TODAY. THE MAJORITY OF THE GUIDANCE STILL KEEPS THE DEEPEST MOISTURE NORTH OF THE LOCAL AREA, ALTHOUGH PRECIPITABLE WATERS RISE TO AROUND 1.7-1.8 INCHES ACROSS MUCH OF THE REGION. AS SEA BREEZE BOUNDARIES ADVANCE INLAND AND AT LEAST ONE SUBTLE VORT MAX APPROACHES, ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED BY AFTERNOON, WITH THE HIGHEST CHANCE (40 PERCENT) OVER THE LAKE REGION AND NORTHEAST SECTIONS OF THE CWA. THE LATEST HRRR DOES SHOW SOME CONVECTION DEVELOPING OVER THE MAINLAND AS EARLY AS 15Z, WHILE AN ORGANIZED LINE OF SHOWERS/STORMS DEVELOPS OVER CENTRAL FLORIDA AROUND 18Z AND PUSHES SOUTHEAST. A FEW STORMS COULD BECOME QUITE STRONG LATER THIS AFTERNOON AND EVENING WITH POTENTIALLY STRONG WIND GUSTS AND SMALL HAIL. AS LOW PRESSURE REMAINS EAST OF FLORIDA ON FRIDAY AND THE REMNANTS OF THE FRONTAL TROUGH APPROACH THE AREA, THE FORECAST MODELS INDICATE A SURGE IN MOISTURE, HEALTHIER LOW LEVEL CONVERGENCE, AND INCREASED INSTABILITY, ESPECIALLY AFTER 18Z. WE WILL CARRY LOW CHANCE POPS (30 PERCENT) FOR MUCH OF THE REGION FRIDAY AFTERNOON. THE REMNANTS OF THE FRONT WILL SLOWLY PASS THROUGH FRIDAY NIGHT INTO SATURDAY EVENING, WITH GRADUALLY IMPROVING CONDITIONS FROM NORTHEAST TO SOUTHWEST. 20-30 POPS ARE STILL WARRANTED THROUGH THE WEEKEND, ALTHOUGH DRIER AIR WILL LIMIT INSTABILITY AS THE LOW LEVEL FLOW BECOMES NORTHEASTERLY. THE PRESSURE GRADIENT WILL ALSO TIGHTEN DURING THIS PERIOD, RESULTING IN BREEZY CONDITIONS AS A BROAD TROUGH LINGERS OFF THE EASTERN SEABOARD AND HIGH PRESSURE MOVES INTO THE SOUTHEAST STATES. MARINE SHOWERS WILL REMAIN POSSIBLE THROUGH SUNDAY WITH SOME ALSO AFFECTING THE EAST COAST, PARTICULARLY AT NIGHT AS COASTAL CONVERGENCE INCREASES. A MID LEVEL TROUGH ALONG THE U.S. EAST COAST WILL KEEP ANY DEEP TROPICAL MOISTURE TO OUR SOUTH AND EAST MONDAY INTO TUESDAY. HOWEVER, INDICATIONS ARE THAT SOME MOISTURE MAY START SURGING NORTHWEST INTO SOUTH FLORIDA BY NEXT WEDNESDAY. && .AVIATION...06Z ISSUANCE...VFR/LIGHT WINDS WILL PREVAIL. WINDS WILL BECOME ONSHORE 5-10 KT BY MID AFTERNOON ALONG WITH ISD-SCT TSRA DEVELOPING...AND FOCUSED INTERIOR/EAST SO INCLUDED VCTS EAST COAST TERMINALS 18-00Z. /GREGORIA && .MARINE...A RIDGE OF HIGH PRESSURE WILL MOVE SLOWLY SOUTH OF THE AREA TODAY. A WEAK PRESSURE GRADIENT WILL REMAIN IN PLACE THROUGH EARLY FRIDAY WITH WINDS 15 KNOTS OR LESS AND SEAS OF 2 TO 4 FEET. WIND SPEEDS WILL BE A BIT STRONGER FRIDAY NIGHT THROUGH SUNDAY. IN ADDITION, A NORTHEAST SWELL OF 2 TO 3 FEET MAY AFFECT PORTIONS OF THE ATLANTIC WATERS THIS WEEKEND. OTHERWISE, ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TODAY THROUGH SATURDAY. && .FIRE WEATHER...NO SIGNIFICANT CONCERNS AS RELATIVE HUMIDITIES WILL REMAIN ABOVE CRITICAL VALUES OVER AT LEAST THE NEXT FEW DAYS. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 90 75 87 74 / 40 20 30 20 FORT LAUDERDALE 91 76 89 75 / 30 20 30 30 MIAMI 92 76 90 75 / 20 20 30 30 NAPLES 90 75 90 73 / 20 10 30 30 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$ DISCUSSION/MARINE/FIRE...14/MJB AVIATION/RADAR...57/DG
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
319 AM CDT THU JUN 14 2012 ...UPDATED THE LONG TERM SECTION... .SYNOPSIS... ISSUED AT 342 PM CDT WED JUN 13 2012 A BROAD WEAK, ZONAL MID LEVEL FLOW PATTERN WA IN PLACE ACROSS WESTERN KANSAS. INCREASING BOUNDARY LAYER MOISTURE WAS OCCURRING AS SOUTHERLY WINDS TRANSPORTED HIGHER CONTENT MOISTURE AIR FROM WESTERN OKLAHOMA AND THE PANHANDLES. FARTHER WEST, A DRYLINE WAS EVIDENT IN THE MESONET POINT DATA ACROSS SOUTHEAST COLORADO, AS WELL AS IN A FINE LINE DEVELOPING ON KPUX RADAR FROM LAMAR, CO SOUTHWEST. && .SHORT TERM...(THIS EVENING THROUGH TOMORROW) ISSUED AT 342 PM CDT WED JUN 13 2012 THE SHORT TERM MODELS HANDLE THE EVOLUTION OF CONVECTION THIS EVENING VERY DIFFERENTLY AND THERE IS RELATIVELY LOW CONFIDENCE IN THIS NEAR TERM FORECAST. THE 12UTC NAM MODEL WOULD INDICATE AND STORMS THAT DEVELOP REMAIN ANCHORED TO THE MUCH HIGHER CAPE/INSTABILITY AXIS OF THE HIGH PLAINS OF COLORADO INTO THE WEST TEXAS PANHANDLE THIS EVENING. AT HIS TIME, THIS NAM SOLUTION SEEMS TO BE MORE LIKELY THAN OTHERS BASED ON THE WEAK FORCING ENVIRONMENT WE ARE DEALING WITH. HOWEVER, WE CANNOT COMPLETELY IGNORE THE RECENT ARW-WRF/NMM RUNS AND HRRR THAT HAVE ELUDED TO CONVECTION OVER EASTERN COLORADO LATER THIS AFTERNOON DEVELOPING A COLD POOL AND SPREADING RAPIDLY INTO THE WESTERN SEVERAL TIERS OF COUNTIES IN THE EVENING HOURS. IF THAT DOES OCCUR, THE MOST PLAUSIBLE OUTCOME WOULD SEEM TO BE MARGINALLY ISOLATED SEVERE THUNDERSTORM WIND GUSTS AND PERHAPS ISOLATED HAIL PUSHING SEVERE LIMITS OF AN INCH AT MOST. HOWEVER, THE WEAKER CONVECTION COULD SPREAD FOR SEVERAL HOURS EASTWARD INTO CENTRAL KANSAS DURING THE LATE EVENING. CONVECTIVE CHANCES ARE JUST AS GOOD OR BETTER ALONG A STRENGTHENING COLD FRONTAL BOUNDARY WHICH SHOULD UNDERGO FRONTOGENESIS FROM WEST CENTRAL KANSAS INTO NORTH CENTRAL KANSAS DURING THE VERY LATE AFTERNOON INTO THURSDAY EVENING. THIS WILL BE BE WEAK FORCING, BUT PERHAPS MORE MODERATE CAPE VALUES BY LATE IN THE DAY. ISOLATED SEVERE CONVECTION COULD BE FOUND THROUGH THE INTERSTATE 70 CORRIDOR, WESTWARD TO SCOTT CITY LATE IN THE AFTERNOON THURSDAY, BUT WIDESPREAD SEVERE IS NOT ANTICIPATED. THE NAM MODEL IS INDICATING THE WARMEST TEMPERATURES AROUND 100 DEGREES, WHILST MOST OTHER NUMERICAL OUTPUT IS INDICATING LOW 90S. TEMPERATURES SHOULD WARM TO SOMEWHERE IN THE MIDDLE THURSDAY AFTERNOON ACROSS SOUTHWEST AND CENTRAL KANSAS. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 316 AM CDT THU JUN 14 2012 FRIDAY THROUGH SATURDAY NIGHT: THE PERIOD FRIDAY THROUGH SATURDAY NIGHT IS A VERY CHALLENGING ONE SENSIBLE WEATHER WISE ACROSS SOUTHWEST KANSAS. WE COULD BE DEALING WITH SEVERAL ROUNDS OF MESOSCALE CONVECTIVE SYSTEMS (MCS) DURING THIS TIME FRAME...EACH OF WHICH WILL HAVE IMPACT ON THE FOLLOWING MCS IN TERMS OF LOCATION, TIMING, AND IMPACTS. WE ARE NOW IN THE PEAK OF MCS SEASON ON THE GREAT PLAINS...SO THIS REALLY COMES AS NO SHOCK TO THIS FORECASTER. SUBSTANTIAL LOW LEVEL MOISTURE WILL BE IN PLACE ALL THE WAY THROUGH SATURDAY...WITH EVAPOTRANSPIRATION ONLY ADDING TO THE ALREADY PLENTIFUL GULF OF MEXICO MOISTURE. THE WESTERN KANSAS REGION WILL REMAIN IN THIS PERTURBED WEST-SOUTHWESTERLY MID AND UPPER LEVEL FLOW PATTERN (ALBEIT QUITE WEAK) AND THE COLD FRONT WHICH WILL BE PUSHING DOWN INTO WEST-CENTRAL KANSAS TODAY WILL MORE OR LESS BECOME QUASI-STATIONARY ACROSS THE SOUTHWEST KANSAS REGION THROUGH SATURDAY (WITH ACTUALLY A REINFORCING WEAK FRONT SATURDAY). THE POPS HAVE BEEN INCREASED TO CHANCE POPS (30 PERCENT) ACROSS PRETTY MUCH ALL OF THE DDC FORECAST AREA FROM LATE FRIDAY INTO FRIDAY NIGHT AND AGAIN LATE SATURDAY/SATURDAY NIGHT. THE ECMWF, GFS, AND NAM MODELS ALL SUGGEST AT LEAST A COUPLE OF MCS`S TO AFFECT PARTS OF WEST-CENTRAL AND SOUTHWEST KANSAS AS THIS FLOW REGIME REMAIN NEARLY UNCHANGED THROUGH LATE SATURDAY. GIVEN THE WIDESPREAD MID 60S DEWPOINTS EXPECTED TO REMAIN ACROSS THE REGION...SOME LOCATIONS WILL PROBABLY RECEIVE QUITE A BIT OF RAINFALL BETWEEN TONIGHT AND SATURDAY NIGHT. WHILE THE OVERALL WIND SHEAR WILL NOT BE THAT IMPRESSIVE FOR SUPERCELL STORMS...THE AMOUNT OF LOW LEVEL MOISTURE AND ASSOCIATED HIGH SURFACE-BASED CAPE WILL COMBINE WITH WEAK DEEP LAYER WIND SHEAR TO SUPPORT SOME MODEST STORM ORGANIZATION AND SEVERE WEATHER POTENTIAL EACH DAY LATE FRI/FRI NIGHT AND LATE SAT/SAT NIGHT. SUNDAY THROUGH WEDNESDAY: THE UPPER LEVEL FLOW PATTERN WILL BE CHANGING BY LATE WEEKEND INTO EARLY NEXT WEEK AS A SIGNIFICANT POLAR JET AFFECTS THE NORTHERN ROCKIES AND NORTHERN PLAINS. THIS WILL ALLOW A DEEP SURFACE LOW/LEE TROUGH TO FORM OVER THE NORTHERN HIGH PLAINS WITH A HOT 850-700MB LAYER DEVELOPING ACROSS THE CENTRAL ROCKIES/NEW MEXICO PLATEAU WHICH WILL SPREAD INTO WESTERN KANSAS. THIS IS NOT A FAVORABLE PATTERN FOR PRECIPITATION ACROSS WESTERN KANSAS...AND THE POP FORECAST WILL REFLECT THIS WITH NO PRECIPITATION IN THE FORECAST SUNDAY THROUGH TUESDAY. AS WE HEAD TO MID-WEEK...ONE OF THE NORTHERN PLAINS SHORTWAVE TROUGH WILL ALLOW A SURFACE FRONT TO REACH WESTERN KANSAS AGAIN PROVIDING THE NEXT CHANCE FOR THUNDERSTORMS OVER WESTERN KANSAS. WHILE WE HAVE SOME 20 POPS IN FOR TUESDAY NIGHT...THE BETTER CHANCE APPEARS TO BE LATE WEDNESDAY/WEDNESDAY NIGHT AT THIS POINT...BUT THIS IS 7 DAYS OUT SO IT IS NOT ALL THAT WISE TO GET TOO DETAILED ABOUT THIS. THE HOTTEST DAY OF THIS STRETCH SHOULD BE MONDAY WITH A FEW 100 DEGREE READINGS EXPECTED MAINLY ACROSS THE WESTERN HALF OF THE DDC FORECAST AREA (ALONG/WEST OF HIGHWAY 283). && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 1241 AM CDT THU JUN 14 2012 RELATIVELY TRANQUIL CONDITIONS ANTICIPATED FOR THE DDC, GCK, AND HYS TERMINALS TONIGHT THROUGH EARLY ON THURSDAY AS VFR CONDITIONS DOMINATE. NONETHELESS...IN ADVANCE OF AN APPROACHING UPPER DISTURBANCE...THE LEE TROUGH CONTINUES TO DEEPEN OVER EASTERN COLORADO WITH A TIGHT PRESSURE GRADIENT EXTENDING INTO WESTERN KANSAS BRINGING BREEZY SOUTH WINDS. ATTENTION THEN SHIFTS TOWARD LATER THIS AFTERNOON TO EVENING AS A COLD FRONT SLIPS INTO WESTERN KANSAS. CONVECTION DEVELOPING ALONG THE FRONT OVER NORTHERN KANSAS WILL LIKELY BECOME NUMEROUS ENOUGH AS IT PROPAGATES SOUTHEAST TO WARRENT INCLUSION IN THE HYS TERMINAL BY LATE AFTERNOON TO EVENING. FURTHER SOUTH...CONVECTION DEVELOPING ALONG THE LEE TROUGH/DRYLINE WILL BE MORE ISOLATED TO SCATTERED IN NATURE AND PROBABILITY OF THESE STORMS BEING WITHIN 5 NM OF DDC AND GCK IS TOO LOW TO INSERT AT THIS POINT. && .PRELIMINARY POINT TEMPS/POPS... DDC 95 65 90 71 / 20 30 20 30 GCK 95 65 91 69 / 30 40 20 30 EHA 95 65 91 67 / 30 40 20 30 LBL 95 67 93 70 / 20 30 20 30 HYS 95 66 87 72 / 30 60 20 30 P28 95 70 89 73 / 10 30 20 20 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...RUSSELL SHORT TERM...RUSSELL LONG TERM...UMSCHEID AVIATION...AJOHNSON
AREA FORECAST DISCUSSION...UPDATED
NWS DODGE CITY KS
111 AM CDT THU JUN 14 2012 ...UPDATED AVIATION SECTION... .SYNOPSIS... ISSUED AT 342 PM CDT WED JUN 13 2012 A BROAD WEAK, ZONAL MID LEVEL FLOW PATTERN WA IN PLACE ACROSS WESTERN KANSAS. INCREASING BOUNDARY LAYER MOISTURE WAS OCCURRING AS SOUTHERLY WINDS TRANSPORTED HIGHER CONTENT MOISTURE AIR FROM WESTERN OKLAHOMA AND THE PANHANDLES. FARTHER WEST, A DRYLINE WAS EVIDENT IN THE MESONET POINT DATA ACROSS SOUTHEAST COLORADO, AS WELL AS IN A FINE LINE DEVELOPING ON KPUX RADAR FROM LAMAR, CO SOUTHWEST. && .SHORT TERM...(THIS EVENING THROUGH TOMORROW) ISSUED AT 342 PM CDT WED JUN 13 2012 THE SHORT TERM MODELS HANDLE THE EVOLUTION OF CONVECTION THIS EVENING VERY DIFFERENTLY AND THERE IS RELATIVELY LOW CONFIDENCE IN THIS NEAR TERM FORECAST. THE 12UTC NAM MODEL WOULD INDICATE AND STORMS THAT DEVELOP REMAIN ANCHORED TO THE MUCH HIGHER CAPE/INSTABILITY AXIS OF THE HIGH PLAINS OF COLORADO INTO THE WEST TEXAS PANHANDLE THIS EVENING. AT HIS TIME, THIS NAM SOLUTION SEEMS TO BE MORE LIKELY THAN OTHERS BASED ON THE WEAK FORCING ENVIRONMENT WE ARE DEALING WITH. HOWEVER, WE CANNOT COMPLETELY IGNORE THE RECENT ARW-WRF/NMM RUNS AND HRRR THAT HAVE ELUDED TO CONVECTION OVER EASTERN COLORADO LATER THIS AFTERNOON DEVELOPING A COLD POOL AND SPREADING RAPIDLY INTO THE WESTERN SEVERAL TIERS OF COUNTIES IN THE EVENING HOURS. IF THAT DOES OCCUR, THE MOST PLAUSIBLE OUTCOME WOULD SEEM TO BE MARGINALLY ISOLATED SEVERE THUNDERSTORM WIND GUSTS AND PERHAPS ISOLATED HAIL PUSHING SEVERE LIMITS OF AN INCH AT MOST. HOWEVER, THE WEAKER CONVECTION COULD SPREAD FOR SEVERAL HOURS EASTWARD INTO CENTRAL KANSAS DURING THE LATE EVENING. CONVECTIVE CHANCES ARE JUST AS GOOD OR BETTER ALONG A STRENGTHENING COLD FRONTAL BOUNDARY WHICH SHOULD UNDERGO FRONTOGENESIS FROM WEST CENTRAL KANSAS INTO NORTH CENTRAL KANSAS DURING THE VERY LATE AFTERNOON INTO THURSDAY EVENING. THIS WILL BE BE WEAK FORCING, BUT PERHAPS MORE MODERATE CAPE VALUES BY LATE IN THE DAY. ISOLATED SEVERE CONVECTION COULD BE FOUND THROUGH THE INTERSTATE 70 CORRIDOR, WESTWARD TO SCOTT CITY LATE IN THE AFTERNOON THURSDAY, BUT WIDESPREAD SEVERE IS NOT ANTICIPATED. THE NAM MODEL IS INDICATING THE WARMEST TEMPERATURES AROUND 100 DEGREES, WHILST MOST OTHER NUMERICAL OUTPUT IS INDICATING LOW 90S. TEMPERATURES SHOULD WARM TO SOMEWHERE IN THE MIDDLE THURSDAY AFTERNOON ACROSS SOUTHWEST AND CENTRAL KANSAS. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 302 PM CDT WED JUN 13 2012 THE EXTENDED PERIOD BEGINNING FRIDAY WILL SEE ONE UPPER SHORT WAVE EXITING THE WESTERN PLAINS OF KANSAS, BRINGING ABOUT A 40 TO 50 PERCENT CHANCE OF THUNDERSTORMS NEAR THE I-70 CORRIDOR AND NORTHWARD, EARLY THURSDAY NIGHT. AFTER MIDNIGHT THURSDAY, THE PRECIP CHANCES WILL CHANGE TO 30 TO 40 PERCENT, AND ONLY IN TREGO, ELLIS AND RUSH COUNTIES. THE NAM MODEL IS HINTING AT QPF FROM 0.60 TO 0.80-INCH IN OUR NORTHWEST FROM HAYS TO SCOTT CITY, BUT HAVE A HARD TIME BUYING THAT MUCH PERCEPTIBLE WATER WILL FALL OUT, BASED ON RECENT TRENDS. TRIMMED THURSDAY NIGHT QPF TO AROUND 0.25 TO 0.30-INCH. AS THAT SHORT WAVE EXITS, ANOTHER SMALL SCALE WAVE IS EJECTED FROM THE LARGE UPPER LOW OFF THE COAST OF BAJA CALIFORNIA. THIS SECOND WAVE IS LESS ORGANIZED THAN THE FIRST, AND WILL BRING THUNDERSTORM CHANCES TO THAT AREA NORTH OF A LINE FROM JOHNSON CITY TO LA CROSSE. THE UPPER BAJA LOW CUTS OFF SATURDAY NIGHT PER THE ECMWF AND GFS MODELS, AND AN UPPER HIGH BEGINS TO BUILD OVER TEXAS. FOR NOW, PLAN TO KEEP SUNDAY AND SUNDAY NIGHT FREE OF PRECIPITATION CHANCES, BUT OUR EXTREME EAST WILL HAVE A SLIGHT CHANCE MONDAY AFTERNOON AS UPPER DIVERGENCE WILL BE OVERHEAD, AND A DOWN SLOPE FLOW WILL BE EVOLVING. A COLD FRONT WILL SINK INTO SOUTHWEST KANSAS MONDAY NIGHT, AND THERE COULD BE A FEW SCATTERED STORMS IN OUR SOUTHEAST ZONES WHERE THE GREATEST MOISTURE WILL BE, SUCH AS SOUTHEAST OF LINE FORM LARNED TO DODGE CITY TO ASHLAND MONDAY NIGHT. THE CR-EXTENDED BLEND PROCEDURE PLACED 30 POPS IN MY EXTREME THREE EASTERN COUNTIES OF STAFFORD, PRATT AND BARBER WEDNESDAY, OR DAY 7. KNOCKED THOSE POPS DOWN TO 20 PERCENT, AS THE TIMING AND PLACEMENT OF THE NEXT WAVE COULD BE JUST ABOUT ANYWHERE AROUND THAT TIME. TEMPERATURES WILL BE RELATIVELY HOT DURING THE EXTENDED. OVERNIGHT MINIMUM TEMPERATURES WILL GENERALLY BE IN THE MID 60S TO LOWER 70S (SE, PRATT AND BARBER COUNTIES), WITH PERHAPS MONDAY NIGHT/TUESDAY MORNING THE COOLEST MORNING WITH MIN TEMPS FROM THE LOWER 60S IN SCOTT CITY TO 70 DEGREES IN MEDICINE LODGE. MAXIMUM TEMPERATURES WILL START OUT FRIDAY IN THE LOWER 90S NORTH OF I-70 AND RANGE TO THE MID 90S ALONG THE OKLAHOMA BORDER. BY SUNDAY, MAXIMUM TEMPERATURES WILL BE IN THE LOWER TO MID 90S ACROSS ALL OF SOUTHWEST KANSAS, THEN WARM TO PERHAPS THE WARMEST DAY MONDAY. HIGHS MONDAY SHOULD TOP OUT IN THE MID TO UPPER 90S, WITH THE ELKHART AREA BEING NEAR THE CENTURY MARK. THE WEAK COLD FRONT WILL SLIP THROUGH MONDAY NIGHT (BEST GUESS), AND KNOCK HIGHS DOWN A NOTCH INTO THE LOWER TO MID 90S BOTH TUESDAY AND WEDNESDAY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 1241 AM CDT THU JUN 14 2012 RELATIVELY TRANQUIL CONDITIONS ANTICIPATED FOR THE DDC, GCK, AND HYS TERMINALS TONIGHT THROUGH EARLY ON THURSDAY AS VFR CONDITIONS DOMINATE. NONETHELESS...IN ADVANCE OF AN APPROACHING UPPER DISTURBANCE...THE LEE TROUGH CONTINUES TO DEEPEN OVER EASTERN COLORADO WITH A TIGHT PRESSURE GRADIENT EXTENDING INTO WESTERN KANSAS BRINGING BREEZY SOUTH WINDS. ATTENTION THEN SHIFTS TOWARD LATER THIS AFTERNOON TO EVENING AS A COLD FRONT SLIPS INTO WESTERN KANSAS. CONVECTION DEVELOPING ALONG THE FRONT OVER NORTHERN KANSAS WILL LIKELY BECOME NUMEROUS ENOUGH AS IT PROPAGATES SOUTHEAST TO WARRENT INCLUSION IN THE HYS TERMINAL BY LATE AFTERNOON TO EVENING. FURTHER SOUTH...CONVECTION DEVELOPING ALONG THE LEE TROUGH/DRYLINE WILL BE MORE ISOLATED TO SCATTERED IN NATURE AND PROBABILITY OF THESE STORMS BEING WITHIN 5 NM OF DDC AND GCK IS TOO LOW TO INSERT AT THIS POINT. && .PRELIMINARY POINT TEMPS/POPS... DDC 65 93 71 95 / 30 20 20 10 GCK 65 93 69 95 / 40 20 20 20 EHA 65 91 66 92 / 40 20 20 10 LBL 67 93 68 94 / 30 20 20 10 HYS 66 90 72 95 / 40 20 30 30 P28 70 94 73 94 / 20 20 20 10 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...RUSSELL SHORT TERM...RUSSELL LONG TERM...BURKE AVIATION...AJOHNSON
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
407 AM CDT THU JUN 14 2012 .DISCUSSION... MODELS HAVE BACKED OFF ADVERTISING FLOW BECOMING SOMEWHAT BLOCKED WITH A TROF DIGGING OVER THE WRN CONUS AND RIDGE AMPLIFYING EAST. SOLUTIONS NOW SHOWING A CUTOFF LOW FORMING OVER THE SWRN STATES BY SATURDAY MORNING WITH FAST FLOW WESTERLIES PREVAILING ACROSS THE NRN TIER STATES. FOR TODAY...SHORTWAVE TROF AND ATTENDANT SFC LOW MOVING ACROSS THE U.S./CAN BORDER WILL DRAG A COLD FRONT ACROSS THE NRN/CNTRL PLAINS AND BE THE FOCUS FOR NEXT ROUND OF THUNDERSTORM ACTIVITY. STRONG LLVL MOISTURE ADVECTION INTO THE REGION PUSH PRECIP WATER VALUES GREATER THAT 1.5"/KI AROUND 40...AND WITH DAYTIME HEATING MUCAPES CATAPULT TO 4500 J/KG. LATEST HIRES RAP AND NMM ARE ADVERTISING ACTIVITY ERUPTING AROUND 18Z ON EDGE OF WEAK CAP...JUST ON THE WRN PERIPHERY OF THE CWA. EXPECT CONVECTION WILL MORE OR LESS CONTINUE ALONG WELL DEFINE BNDRY LYR MOISTURE CONVG ZONE WELL INTO TONIGHT AND FRIDAY. BY FRIDAY NIGHT...ANOTHER SHORTWAVE TRAVERSING THE U.S./CAN BORDER WILL DRAG A COLD FRONT INTO THE CNTRL PLAINS. SMALL POPS ARE ALREADY IN PLACE THRU SUNDAY FOR THIS SO NO NEED FOR ADJUSTMENTS. OTHERWISE...APPEARS THAT SUBSEQUENT SHORTWAVES AND ATTENDANT SFC BOUNDARIES WILL KEEP AN UNSETTLED PATTERN IN PLACE THRU EARLY NEXT WEEK. DEE && .AVIATION... 06Z TAFS FOR KOFK...KLNK AND KOMA. ISOLATED STORMS OVER EASTERN NEBRASKA AT START OF THE PERIOD EXPECTED TO WEAKEN THROUGH 09Z. ADDITIONAL DEVELOPMENT POSSIBLE AFTER 15Z AS MID LEVEL WAVE AND SURFACE COLD FRONT APPROACH EASTERN NEBRASKA. VFR CONDITIONS OUTSIDE OF THUNDERSTORMS. DF && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$
AREA FORECAST DISCUSSION
NWS HASTINGS NE
329 AM CDT THU JUN 14 2012 .SHORT TERM...TODAY THROUGH SATURDAY NIGHT. THE MAIN PROBLEM FOR THE SHORT TERM PERIOD WILL FOCUS ON THE NUMEROUS THUNDERSTORM CHANCES ALONG FRONTAL BOUNDARIES PUSHING THROUGH THE REGION. UPPER LEVEL ANALYSIS REVEALS MOSTLY ZONAL FLOW ACROSS THE CONUS...HOWEVER...A DEEPENING TROUGH ACROSS WESTERN CANADA AND NUMEROUS SHORT WAVES ARE EXPECTED TO EFFECT THE CENTRAL PLAINS THROUGH THE PERIOD. IN THE MID LEVELS...THE TROUGH APPEARS TO DEEPEN SOME...WHILE SURFACE LOW PRESSURE MOVES ACROSS THE FRONT RANGE OF THE ROCKIES INTO WESTERN NEBRASKA AND SOUTHERN SOUTH DAKOTA. A COOL FRONTAL BOUNDARY ALONG THE WESTERN PANHANDLE CAN BE SEEN WITH A WIND SHIFT IN THE OBSERVATIONS AND ALSO ON RADAR WITH A FEW LIGHT SHOWERS PUSHING OFF THE BOUNDARY IN THE PANHANDLE. THROUGHOUT THE DAY TODAY...THIS FRONTAL BOUNDARY WILL CONTINUE TO SLIDE EASTWARD ALONG THE PLAINS...WHILE THE MAIN PARENT UPPER LEVEL LOW PUSHES EASTWARD WELL NORTH OF THE PLAINS. WITH THE FRONT BEING THE MAIN FORCING MECHANISM...THE MODELS TRY TO GENERATE A FEW SHOWERS ACROSS WESTERN NEBRASKA THIS MORNING...AS THE FRONT ENCOUNTERS MORE MOIST AIR AND SLIGHTLY HIGHER DEWPOINTS. INITIAL THINKING IS MORE LIKE THE HRRR SOLUTION...IN WHICH SHOWERS DEVELOP ACROSS NORTHERN NEBRASKA THIS MORNING 12Z TO 15Z TIME FRAME BEFORE UNZIPPING SOUTHWEST ACROSS THE NORTHWEST PORTION OF THE FORECAST AREA DURING THE 15Z TO 18Z TIME FRAME. BY 18Z...INSTABILITY VALUES ARE QUITE HIGH WITH NEARLY 2500 TO 4000 J/KG EXPECTED DEPENDING ON THE MODEL. DEEP LAYER BULK SHEAR IS MINIMAL AT BEST...BUT COULD SEE SOME STRONG TO MARGINALLY SEVERE THUNDERSTORMS. AS THE FRONT CONTINUES TO SAG SOUTHEAST ACROSS THE FORECAST AREA DURING THE EVENING AND OVERNIGHT HOURS...THREAT AND PRECIPITATION CHANCES ALSO SHIFT SOUTHEAST. AGAIN THE NOSE OF THE LOW LEVEL JET NOSES IN ACROSS THE SOUTHEAST WHICH COULD HELP CONTINUE CONVECTION INTO THE OVERNIGHT HOURS ACROSS THE SOUTHEAST. FOR THE FRIDAY TIME FRAME...THE MAIN THINKING IS THAT WITH THE EXCEPTION OF THE FAR SOUTH AND SOUTHEAST WHERE THE FRONT REMAINS STALLED...MOST LOCATIONS WILL BE DRY. HOWEVER...THAT BEING SAID...WITH A FEW MODELS SUGGESTING GOOD SOUTHERLY FLOW IN THE MID LEVELS...COULD SEE SOME OVERRUNNING OF THE FRONTAL BOUNDARY WHICH COULD GENERATE SOME SHOWERS TO THE NORTH OF THE FRONT. AT THIS POINT...DECIDED TO LEAVE CHANCES ACROSS THE SOUTH AND SOUTHEAST...AND SLIGHTS ACROSS THE NORTHWEST FOR THAT POSSIBILITY. BY FRIDAY NIGHT...THE FRONT IS EXPECTED TO LIFT NORTHWARD...AND WITH THE DEVELOPMENT OF THE LOW LEVEL JET...EXPECTING THE POSSIBILITY OF MORE WIDESPREAD PRECIPITATION CHANCES TO THE NORTH OF THE BOUNDARY. ANOTHER UPPER LEVEL SHORT WAVE...SURFACE FRONTAL BOUNDARY COMBINATION IS ALSO IN THE WORKS TO MOVE THROUGH SATURDAY MORNING...BRINGING YET ANOTHER CHANCE SHOWERS AND THUNDERSTORMS. MODELS REMAIN INCONSISTENT HOWEVER...WITH TIMING AND PLACEMENT OF THIS NEXT SYSTEM. THAT BEING SAID...SATURDAY COULD BE AN INTERESTING REGARDING SEVERE WEATHER CHANCES INSTABILITY VALUES AHEAD OF THE FRONT ARE EXPECTED TO RANGE NEAR 2500 TO 4000 J/KG DEPENDING ON THE MODEL. ALSO...DEEP LAYER BULK SHEAR APPEARS TO BE A BIT BETTER AHEAD OF THE BOUNDARY...WITH A FEW MODELS HINTING AT NEAR 30 KTS. MADE VERY FEW CHANGES TO TEMPERATURES IN THE SHORT TERM PERIOD. DECIDED TO LOWER LOW TEMPERATURES A BIT ACROSS THE NORTHWEST ON SATURDAY EVENING BEHIND THE FRONTAL BOUNDARY. .LONG TERM...12Z SUNDAY THROUGH WEDNESDAY. MAIN FORECAST CONCERNS WILL BE CHANCES FOR INTERMITTENT THUNDERSTORMS MONDAY NIGHT THROUGH WEDNESDAY AND TEMPERATURES. AN ACTIVE PATTERN CONTINUES ACROSS THE REGION THROUGH THE PERIOD. THERE ARE SEVERAL WAVES THAT MOVE THROUGH THE FORECAST AREA AND EACH OF THEM HAVE A SMALL POTENTIAL FOR SOME THUNDERSTORMS. WITHOUT A BOUNDARY THOUGH THEY SHOULD HAVE SOME DIFFICULTY CAUSING THUNDERSTORMS. THERE ARE SOME SLIGHT DIFFERENCES IN THE MODELS AND HOW STRONG THE UPPER LEVEL WAVES THAT MOVE THROUGH ARE. THE GFS IS STRONGER THAN THE ECMWF AND THEREFORE HAS MORE PRECIPITATION ACROSS THE AREA. FOR SUNDAY THROUGH MONDAY THERE IS A SURFACE LOW AND COLD FRONT DEVELOPING ON THE HIGH PLAINS AND IT STARTS TO MOVE THROUGH THE AREA MONDAY. WILL KEEP THIS PERIOD DRY. TEMPERATURES WILL BE WARM WITH HIGHS IN THE UPPER 80S TO MID 90S FOR HIGHS AND LOWS AROUND 70. THE FRONT WASHES OUT AS ANOTHER LOW DEVELOPS ON THE HIGH PLAINS MONDAY NIGHT. THE FRONT FINALLY MOVES THROUGH THE FORECAST AREA TUESDAY NIGHT...BUT IT STALLS JUST TO THE SOUTHEAST OF THE FORECAST AREA BY WEDNESDAY. WITH THE FRONT MOVING INTO THE NORTH WILL HAVE A CHANCE FOR THUNDERSTORMS IN THE NEBRASKA PART OF THE FORECAST AREA WITH THE STRONGER UPPER LEVEL WAVE IN THE NORTH. THE FRONT MOVES THROUGH THE AREA ON TUESDAY AND THUNDERSTORMS DEVELOP ALONG THE FRONT TUESDAY EVENING AND OVERNIGHT. THE THUNDERSTORMS WILL LINGER INTO WEDNESDAY IN THE SOUTHEAST AS THE FRONT STALLS AND THE MAIN UPPER LEVEL TROUGH MOVES TO THE EAST OF THE AREA. && .PREV DISCUSSION... /ISSUED 1226 AM CDT THU JUN 14 2012/ AVIATION...06Z TAF. STILL HAVE SOME CIRRUS AROUND FROM EARLIER THUNDERSTORMS. THIS SHOULD LINGER THROUGH MUCH OF THE NIGHT. THE MAIN QUESTION FOR THIS FORECAST WILL BE WHEN THERE WILL BE THUNDERSTORMS. EXPECT THAT THUNDERSTORMS WILL DEVELOP ALONG A COLD FRONT AND MOVE INTO THE KGRI TERMINAL AREA DURING THE AFTERNOON...LINGERING INTO THE EARLY EVENING. THE THUNDERSTORMS SHOULD COME TO AN END DURING THE EVENING...AS THE COLD FRONT MOVES THROUGH AND WINDS TURN TO THE EAST. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ SHORT TERM...SALTZMAN LONG TERM/AVIATION...JCB
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
149 AM EDT THU JUN 14 2012 .SYNOPSIS... A COLD FRONT WILL CONTINUE TO MOVE ACROSS THE AREA OVERNIGHT...AND WILL BE SOUTH OF THE SOUTH SANTEE RIVER BEFORE DAYBREAK. HIGH PRESSURE WILL STRONGLY BUILD ACROSS THE AREA THURSDAY...BRINGING A RELATIVELY COOL AND DRY PATTERN WHICH WILL PERSIST INTO NEXT WEEK. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... AS OF 1040 PM WEDNESDAY...ISOLATED WEAK CONVECTION TO CONTINUE THROUGH MIDNIGHT ACROSS THE GRAND STRAND OF SC. LATEST RUC HRLY MODEL OUTPUT INDICATES YET ADDITIONAL WEAK SHEARED MID LEVEL VORT INTERACTING WITH A WEAK SFC BOUNDARY EVIDENT WITH THE LATEST HRRR SFC WIND FIELD. THE SFC BOUNDARY SHOULD PUSH SOUTH OF THE ILM CWA BY 2 AM THE LATEST...AND AS A RESULT HAVE KEPT A LOW CHANCE FOR POPS ACROSS THE GRAND STRAND TIL THIS BOUNDARIES DEPARTURE. DRIER AIR IE. LOWER DEWPOINTS...WILL BE A TAD SLOWER IN PROGRESSING ACROSS THE ILM CWA DURING THE OVERNIGHT. AS A RESULT HAVE TWEAKED OVERNIGHT MINS AND HRLY DEWPOINTS UPWARDS...ESPECIALLY ALONG THE IMMEDIATE COAST... TO ACCOMMODATE. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 3 PM WEDNESDAY...A COLD FRONT WILL BE OFF THE COAST AS THE FORECAST PERIOD BEGINS AND A LOW PRESSURE AREA WILL DEVELOP ALONG THE FRONT. THIS WILL INCREASE THE NORTHERLY WINDS OVER THE REGION AND COOLER AND DRIER AIR WILL SHIFT INTO THE AREA. HIGHS WILL BE IN THE LOWER 80S AND LOWS IN THE LOWER 60S. WITH THE DRIER AIR THE CHANCES OF PRECIPITATION ARE NIL. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... AS OF 3 PM WEDNESDAY...SURFACE HIGH PRESSURE NOSING IN FROM THE NORTHEAST WHILE OFFSHORE MID LEVEL TROUGH DEVELOPS OFF THE COAST FOR MUCH OF THE PERIOD. THIS LEADS TO A DEEP NORTHEASTERLY FLOW ACROSS THE COASTAL CAROLINAS FOR MOST OF THE PERIOD. TEMPERATURES WILL AVERAGE ROUGHLY A CATEGORY BELOW CLIMO BY DAY AND PERHAPS A FEW DEGREES MORE BY NIGHT...THERE COULD EVEN BE A FEW UPPER 50S WELL INLAND. THE SURFACE RIDGE BEGINS TO PROGRESS TO THE EAST BY TUESDAY TURNING THE FLOW FROM NE TO MORE EAST OR SOUTHEAST. THIS SHOULD LEAD TO SOME MOISTURE ADVECTION AND PERHAPS ISOLATED EARLY MORNING SHOWERS ALONG THE COAST. TEMPERATURES WILL ALSO TREND UPWARD SLIGHTLY. && .AVIATION /06Z THURSDAY THROUGH MONDAY/... AS OF 06Z...COLD FRONT HAS PUSHED S OF KILM AND KLBT AS OF 04Z AND WILL MOVE ACROSS THE REMAINDER OF THE TERMINALS THROUGH 08Z. A LINE OF SHOWERS HAS DEVELOPED ALONG A PORTION OF THE BOUNDARY AND WILL INCLUDE VCSH FOR KMYR AND KCRE TIL 08Z. VFR CONDITIONS ARE EXPECTED THROUGH SUNRISE AS A N WIND BRINGS INCREASINGLY COOLER AND DRIER AIR ACROSS THE TERMINALS. AFTER SUNRISE HIGH PRESSURE WILL SHIFT WEST AS LOW PRESSURE DEVELOPS OFFSHORE. AN INCREASING PRESSURE GRADIENT BETWEEN THE TWO SYSTEMS WILL CAUSE N TO NE WINDS TO INCREASE...WITH OCCASIONAL GUSTS TO 20-25 KNOTS...ESPECIALLY AT THE COASTAL TERMINALS. WRAP AROUND MOISTURE FROM LOW PRESSURE OFFSHORE WILL MOISTEN THE LOW-LEVELS ENOUGH THAT LOW VFR CEILINGS WILL LIKELY DEVELOP DURING THE LATE MORNING AND AFTERNOON. THERE IS A CHANCE CEILINGS COULD DROP AT TIMES TO MVFR...BUT CONFIDENCE IS LOW ESPECIALLY WITH TIMING. THERE IS A SLIGHT CHANCE OF ISOLATED LIGHT SHOWERS DURING THE AFTERNOON NEAR THE COASTAL TERMINALS...BUT WILL NOT MENTION IN TAFS ATTM. EXTENDED OUTLOOK...MAINLY VFR THROUGH THE FORECAST PERIOD WITH NORTHEASTERLY WINDS. A CHANCE OF SHOWERS SUNDAY AND MONDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 1040 PM WEDNESDAY...NE WINDS WILL BECOME DOMINATE DURING THE OVERNIGHT...INITIALLY 5 TO 10 KT...THEN FURTHER INCREASE TO 10 TO 15 KT DURING THE THU PRE-DAWN HRS. THIS A RESULT OF THE FRONT MOVING FURTHER SOUTH AND EAST FROM THE ILM COASTAL WATERS AS DECENT RIDGING FROM THE HIGH CENTERED OVER SE CANADA BECOMES MORE DOMINANT. SPEEDS COULD REACH AROUND 15 KT BY DAYBREAK FOR THE WATERS FROM CAPE FEAR NORTHWARD AS THE SFC PG TIGHTENS. OVERNIGHT SIGNIFICANT SEAS WILL RUN 2 TO 3 FT...EXCEPT UP TO 4 FT OFF CAPE FEAR. WIND DRIVEN WAVES WILL CONTINUE THE MORE DOMINANT PLAYER WITH REGARD TO SIG SEAS... WITH DOMINANT PERIODS AROUND 6 SECONDS. THE LAST OF THE CONVECTION COULD AFFECT THE NEAR SHORE WATERS SOUTH OF LITTLE RIVER INLET EARLY INTO THE PRE-DAWN HRS OF THU. SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 3 PM WEDNESDAY...A COLD FRONT WILL BE OFF THE COAST AS THE FORECAST PERIOD BEGINS AND A LOW PRESSURE AREA WILL DEVELOP ALONG THE FRONT. THIS WILL INCREASE THE NORTHERLY WINDS OVER THE REGION AND COOLER AND DRIER AIR WILL SHIFT INTO THE AREA. HIGHS WILL BE IN THE LOWER 80S AND LOWS IN THE LOWER 60S. WITH THE DRIER AIR THE CHANCES OF PRECIPITATION ARE NIL. LONG TERM /SATURDAY THROUGH MONDAY/... AS OF 3 PM WEDNESDAY...RATHER UN-CLIMATOLOGICAL NE FLOW TO BE IN PLACE THROUGH THE PERIOD. HIGH PRESSURE NOSED INTO THE CAROLINAS FROM THE NORTHEAST FOR MUCH OF THE TIME. IN THIS COAST- PARALLEL FLOW THERE MAY BE A CONSIDERABLE GRADIENT IN WAVE HEIGHT FROM THE COAST TO THE 20NM FORECAST ZONE BORDER...AND FUTURE FORECASTS WILL HAVE TO DETERMINE WHETHER SOME 6 FT SEAS WILL BE CLOSE ENOUGH TO WARRANT A SMALL CRAFT ADVISORY ON SATURDAY. A SLIGHT EASE IN THE GRADIENT TRANSLATING TO AN APPROXIMATE 5KT DROP IN SUSTAINED WIND SPEED FOR SUNDAY SHOULD PRECLUDE ANY ADVISORIES BUT SCEC HEADLINES ARE TOUGH TO RULE OUT EARLY ON. AN EASTWARD JOG OF THE HIGH ON MONDAY WILL WEAKEN THE WINDS EVEN FURTHER RESULTING IN A MORE PRONOUNCED ABATING OF THE SEAS. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ NEAR TERM...DCH SHORT TERM...HAWKINS LONG TERM...MBB AVIATION...MRR/RJD
AREA FORECAST DISCUSSION
NWS NORMAN OK
1147 PM CDT WED JUN 13 2012 .AVIATION... SCATTERED MVFR CEILINGS ARE EXPECTED IN WESTERN OKLAHOMA TONIGHT. OTHERWISE VFR CONDITIONS ARE EXPECTED. THUNDERSTORMS MAY AFFECT SOUTH CENTRAL OKLAHOMA AROUND SUNRISE. && .PREV DISCUSSION... /ISSUED 1000 PM CDT WED JUN 13 2012/ DISCUSSION... TRIM POPS ACROSS ALL BUT WESTERN NORTH TEXAS AND SOUTHWEST OKLAHOMA. STORMS COMING OFF HIGHER TERRAIN HAVING TROUBLE AND WILL LIKELY DISSIPATE BEFORE MAKING IT INTO BODY OF OKLAHOMA. ACTIVITY OVER FAR SOUTHEAST OKLAHOMA IS EXPECTED TO SLOWLY WEAKEN AND SHIFT SOUTH. MAIN AREA OF STORMS OVERNIGHT AND EARLY FRIDAY MAY BE ASSOCIATED WITH WEAK DISTURBANCE SHIFTING EAST ACROSS SOUTHWEST TEXAS. SCATTERED STORM DEVELOPMENT TRYING TO GET GOING SOUTH AND EAST OF LUBBOCK...AND LATEST RUN OF HRRR DOES KEEP DEVELOPING STORMS FARTHER NORTH AND EAST INTO WESTERN NORTH TEXAS OVERNIGHT. THEREFORE WILL LEAVE CHC POPS GOING THERE. WITH STEEP LAPSE RATES...CANNOT RULE OUT SOME SEVERE HAIL LATE TONIGHT ACROSS WESTERN NORTH TEXAS AND SOUTHWEST OKLAHOMA IF STORMS CAN GET GOING. && .PRELIMINARY POINT TEMPS/POPS... OKLAHOMA CITY OK 67 89 70 92 / 20 20 20 20 HOBART OK 67 90 69 92 / 30 20 20 10 WICHITA FALLS TX 72 92 73 96 / 40 20 20 10 GAGE OK 68 88 70 90 / 20 30 40 20 PONCA CITY OK 69 88 70 92 / 10 20 10 30 DURANT OK 70 89 71 93 / 40 30 30 10 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...NONE. TX...NONE. && $$ 03/09/09
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
1148 PM CDT WED JUN 13 2012 .DISCUSSION... /SEE BELOW FOR AVIATION DISCUSSION/ && .AVIATION... MVFR STRATUS POSSIBLE AT KJCT AND KBBD AS SE LOW LEVEL MOISTURE MOVES UP FROM THE GULF. CIGS SCATTERING OUT MID MORNING. STRATUS SHOULD REMAIN EAST OF KSJT KABI AND KSOA. SOUTH WINDS GUST TO 25 KTS AT KSJT AND KABI MID MORNING LEE THROUGH STRENGTHENS. ISOLATED THUNDERSTORMS POSSIBLE...BUT COVERAGE TOO LOW TO MENTION IN TAFS. 04 && .PREV DISCUSSION... /ISSUED 932 PM CDT WED JUN 13 2012/ UPDATE... NO CHANGES TO FORECAST. DISCUSSION... UPPER SHORTWAVE WAS MOVING INTO WEST TEXAS THIS EVENING...HOWEVER CONVECTIVE DEVELOPMENT WAS SCARCE...WITH ONLY SCATTERED SHOWERS IN THE TRANSPECOS TRYING TO CROSS THE PECOS RIVER IN WESTERN CROCKETT COUNTY. WHILE CHANCE OF STORMS APPEARS REMOTE TONIGHT WITH INCREASING CAP...WILL CONTINUE TO KEEP A SLIGHT CHANCE OF STORMS AS UPPER SHORTWAVE MOVES ACROSS THE REGION. PREVIOUS GFS AND NAM MODELS WERE INDICATING THE BEST CHANCE OF RAIN AFTER 10 PM. 04 PREV DISCUSSION... /ISSUED 559 PM CDT WED JUN 13 2012/ DISCUSSION... SEE 00Z AVIATION DISCUSSION BELOW. AVIATION... VFR CONDITIONS ARE EXPECTED THE NEXT 24 HOURS. WINDS WILL BE SOUTH AT 10 TO 15 KNOTS WITH A FEW GUSTS TO 20 KNOTS. WATCHING A FEW TSTMS OVER SOUTHWEST TEXAS. THIS ACTIVITY WILL PROBABLY REMAIN WELL WEST OF THE TERMINALS. 21 PREV DISCUSSION... /ISSUED 348 PM CDT WED JUN 13 2012/ SHORT TERM... WE HAD ISOLATED WEAK CONVECTION EARLY TODAY BUT THIS HAS SINCE DISSIPATED. SKIES HAVE BECOME MOSTLY CLEAR TO PARTLY CLOUDY ACROSS THE CWA LIKELY IN RESPONSE TO SUBSIDENCE IN THE WAKE OF THE DEPARTING MCV ALONG THE RED RIVER VALLEY. A WEAK SURFACE...YET DISCERNIBLE...BOUNDARY STILL EXISTS OVER THE SOUTHWEST CWA PER THE KSJT WSR-88D BUT THIS FEATURE REMAINS BENIGN AT THIS TIME. LOOKING WEST...MID LEVEL RADAR ECHOES HAVE BEEN INCREASING ACROSS SOUTHWEST TX THIS AFTERNOON AHEAD OF AN APPROACHING SHORTWAVE. AS THIS SYNOPTIC SCALE ASCENT OVERSPREADS THE AREA AND SURFACE TEMPS WARM INTO THE MID/UPPER 90S...I ANTICIPATE CONVECTION DEVELOPING IN THE VICINITY OF THE CWA. CONFIDENCE IS FAIRLY LOW THAT WE WILL SEE WIDESPREAD THUNDERSTORMS BUT SEVERAL VERSIONS OF THE HIRES WRF AND THE HRRR ALL AGREE IN THUNDERSTORMS FORMING OVER THE CENTRAL/EASTERN COUNTIES. A LOOK AT THE SPC MESO ANALYSIS PAGE DEPICTS SBCAPE VALUES ON THE ORDER OF 2500-3500 J/KG WITH EFFECTIVE SHEAR VALUES BETWEEN 40-50 KTS. THE QUESTION WILL BE WHETHER OR NOT THE CAP WILL GIVE WAY. THUS...WE DO HAVE A CONDITIONAL THREAT FOR SEVERE WEATHER BUT I AM PLAYING THIS RATHER CONSERVATIVE FOR NOW THINKING THAT THE CAP WILL HOLD FOR THE MOST PART AND ANY CONVECTIVE INITIATION WILL LIKELY BE DELAYED UNTIL WELL AFTER PEAK HEATING. THUS...I AM ONLY CARRYING 20 POPS FOR THE PERIOD BEGINNING AT 00Z. OVERNIGHT TEMPS WILL FALL INTO THE LOWER 70S /BUT WILL LIKELY BE LOWER IF CONVECTION DOES DEVELOP/. GENERALLY DRY AND WARM CONDITIONS ARE EXPECTED FOR THURSDAY WITH SOUTH WINDS INCREASING TO 10-20 MPH ACROSS THE CWA. HIGHS ARE EXPECTED TO BE IN THE MID/UPPER 90S. JOHNSON LONG TERM... THURSDAY NIGHT INTO FRIDAY...THE UPPER LEVEL LOW THAT IS CURRENTLY OVER SOUTHERN CALIFORNIA TODAY WILL BE ENVELOPED BY ANOTHER LOW THAT WILL MOVE SOUTH ALONG THE CALIFORNIA COAST. THERE WILL BE AN UPPER LEVEL TROUGH OVER THE GULF COAST REGION AS WELL WHILE WEST CENTRAL TEXAS WILL BE IN BETWEEN UNDERNEATH RIDGING. FOR THIS REASON...WILL GO WITH TEMPERATURES SLIGHTLY WARMER THAN GUIDANCE FOR FRIDAY AND SATURDAY. HAVE NOT EXPANDED ANY OF THE INHERITED POPS FRIDAY AFTERNOON AND EVENING. IT STILL APPEARS THAT THE LOW WILL BE TOO FAR WEST TO DIRECTLY INFLUENCE US...AND THAT MOST OF THE CONVECTION WILL GET GOING IN THE HIGHER TERRAIN OF THE WEST TEXAS AREA...THEN MOVE SLOWLY TO THE NORTHEAST DURING THE EVENING HOURS...POSSIBLY MAKING THEIR WAY INTO OUR WESTERN TIER OF COUNTIES BEFORE DISSIPATING. THE UPPER LEVEL RIDGING EXPANDS THROUGH THE WEEKEND ACROSS TEXAS AND THE REST OF THE SOUTHWESTERN U.S. THIS WILL PUSH THE MID/UPPER LEVEL LOW BACK OUT TO THE PACIFIC...AND KEEP OUR TEMPERATURES WARMER THAN NORMAL WITH LITTLE CHANCE FOR PRECIPITATION. BY TUESDAY OF NEXT WEEK...A WEAK MID/UPPER LEVEL TROUGH DEVELOPS ACROSS THE EASTERN HALF OF TEXAS...AND LOOKS TO DRIFT SLOWLY WEST/SOUTHWEST ACROSS THE SOUTHERN HALF OF THE STATE. THIS COULD RESULT IN SOME LOWERED TEMPERATURES...AND THE GFS/ECMWF ALSO TRY TO SHOW SOME SHRA/TSRA DEVELOPING ACROSS OUR SOUTHEASTERN COUNTIES. WILL HOLD OFF ON INTRODUCING ANY WX AT THIS TIME...BUT IT WILL BE WORTH WATCHING. 20 && .PRELIMINARY POINT TEMPS/POPS... ABILENE 72 93 72 94 71 / 20 10 10 10 10 SAN ANGELO 73 98 73 98 71 / 20 10 10 10 10 JUNCTION 74 98 73 94 72 / 20 10 10 10 10 && .SJT WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 99/99/04
AREA FORECAST DISCUSSION...UPDATED
NWS AMARILLO TX
1124 PM CDT WED JUN 13 2012 .AVIATION... UPPER RIDGE WILL PREVAIL ACROSS THE PANHANDLES TONIGHT THROUGH THURSDAY MORNING...AND THEN WEAKEN BY LATE THURSDAY AS AN UPPER TROUGH MOVES INTO THE PANHANDLES. VFR CONDITIONS WILL PREVAIL THROUGH THE TAF FORECAST PERIOD. HOWEVER...SOME CONVECTION WILL BE POSSIBLE AFTER 20Z THURSDAY WHICH COULD POSSIBLY AFFECT ALL THREE TAF SITES. BEST CHANCES FOR ANY CONVECTION WILL BE AT THE GUYMON TAF SITE...AND ALSO THE DALHART TAF SITE...THURSDAY AFTERNOON AND EVENING AS A COLD FRONT PUSHES SOUTH INTO CENTRAL AND WESTERN OR SOUTHWESTERN KANSAS BY 00Z FRIDAY. WILL HOLD OFF MENTIONING THE CONVECTION WITH THIS TAF FORECAST PACKAGE...HOWEVER LATER SHIFTS MAY NEED TO ADDRESS THIS CONCERN. SOUTHERLY TO SOUTHEASTERLY WINDS 10 TO 20 KNOTS EXPECTED WITH SOME GUSTS TO 30 KNOTS POSSIBLE. SCHNEIDER && .PREV DISCUSSION... /ISSUED 914 PM CDT WED JUN 13 2012/ UPDATE... THE 00Z KAMA /AND KDDC/ SOUNDINGS SHOWED A PRONOUNCED CAPPING INVERSION AROUND 700MB IN PLACE ACROSS THE AREA...WHICH IS ALSO INDICATED BY LAPS DATA. THIS CAPPING ALONG WITH A LACK OF ANY SIGNIFICANT FORCING HAS KEPT THE CWA CONVECTION FREE SO FAR THIS EVENING. CU THAT TRIED TO GROW ALONG A WEAK NORTH/SOUTH LOW-LEVEL CONVERGENT AXIS EAST OF AN AMARILLO TO GUYMON LINE HAS RECENTLY DISSIPATED WITH ONSET OF NOCTURNAL COOLING AND RESULTANT STRENGTHENING CIN. A FEW THUNDERSTORMS THAT DEVELOPED OVER THE MOUNTAINS OF NM CONTINUE TO SLOWLY WORK EAST ACROSS EASTERN NM...WHILE CONVECTION THAT DEVELOPED ALONG A SURFACE TROUGH OVER SOUTHEAST CO INTO WESTERN KS HAS DISSIPATED. THERE IS STILL SOME POTENTIAL FOR THUNDERSTORMS ACROSS THE PANHANDLES TONIGHT...HOWEVER BELIEVE COVERAGE WILL BE FAIRLY ISOLATED. A WEAK MID-LEVEL SHORTWAVE APPEARS TO BE MOVING EAST ACROSS CENTRAL NM PER WATER VAPOR IMAGERY...AND A 40 KT SOUTHERLY LLJ IS EXPECTED TO DEVELOP ACROSS THE EASTERN HALF OF THE FORECAST AREA TONIGHT. WEAK FORCING FROM THE SHORTWAVE AND/OR WARM AIR ADVECTION/MOISTURE ADVECTION ALONG THE LLJ AXIS MAY ALLOW CONVECTION TO WORK IN FROM NM/FAR SOUTHERN CO OR FOR NEW CONVECTION TO DEVELOP. NORTHWEST AREAS WILL BE FAVORED FOR ANY ISOLATED STORMS THROUGH MIDNIGHT AS STORMS MAY WORK IN FROM THE WEST...WITH THE FOCUS THEN SHIFTING TO THE EASTERN HALF TO TWO THIRDS OF THE CWA OVERNIGHT ALONG THE LLJ AXIS. HOWEVER...BELIEVE SHORTWAVE RIDGING AND CAPPING IN PLACE WILL KEEP ANY CONVECTION ISOLATED...WITH FORECAST SOUNDINGS SUGGESTING THAT THE MID- LEVEL CAPPING WILL LIKELY MAKE IT TOUGH EVEN FOR ELEVATED CONVECTION TO DEVELOP TONIGHT. WILL KEEP THUNDERSTORM CHANCES IN THE FORECAST GIVEN THE LLJ PRESENCE...WEAK SHORTWAVE OVER NM...AND SOME LINGERING CONVECTION SLOWLY WORKING THIS WAY...BUT KEEP THEM ON THE LOW SIDE DUE TO ANTICIPATED WEAK FORCING AND CAPPING CONCERNS. IF STORMS ARE ABLE TO OVERCOME THE CAP...THERE WILL BE AMPLE INSTABILITY TO TAP INTO ABOVE IT /MUCAPES OF 2000-3000 J/KG/ TO SUPPORT PRIMARILY A LARGE HAIL THREAT GIVEN EXPECTED ELEVATED NATURE OF STORMS...ALTHOUGH CAN/T RULE OUT SOME STRONG WINDS. VARIOUS SHORT TERM MODELS ARE STILL GIVING VERY MIXED SIGNALS FOR THUNDERSTORM POTENTIAL OVERNIGHT...RANGING FROM VIRTUALLY NO ACTIVITY INDICATED BY THE HRRR TO A SOLID LINE OF STORMS DEVELOPING IN THE OUN WRF. AM SIDING WITH THE MUCH LESSER COVERAGE/CHANCES DUE TO THE REASONS STATED ABOVE. ALSO...NOT ANTICIPATING ANY SIGNIFICANT COLD POOL PRESENCE TO AID IN MORE WIDESPREAD DEVELOPMENT TONIGHT GIVEN VERY ISOLATED NATURE OF ONGOING CONVECTION. SO TO SUMMARIZE...SOME POTENTIAL FOR ISOLATED STORMS WILL CONTINUE TONIGHT BUT EXPECT COVERAGE TO BE PRETTY MINIMAL. HOWEVER IF STORMS DO DEVELOP...THEY COULD BE STRONG OR SEVERE WITH HAIL THE MAIN CONCERN. KB PREV DISCUSSION... /ISSUED 633 PM CDT WED JUN 13 2012/ AVIATION... AN UPPER RIDGE OVER THE PANHANDLES THIS EVENING WILL GIVE WAY TO AN UPPER TROUGH AFTER 06Z THURSDAY. VFR CONDITIONS ARE EXPECTED TO PREVAIL...HOWEVER SOME CONVECTION COULD POSSIBLY DEVELOP AFTER 06Z THURSDAY IN RESPONSE TO THE UPPER TROUGH. THE AMARILLO TAF SITE WOULD BE THE TAF SITE WHICH COULD BE AFFECTED LATER TONIGHT BY ANY CONVECTION. WILL HOLD OFF NOW MENTIONING IN THE TAF FORECAST AS CONFIDENCE REMAINS LOW. SOUTHERLY TO SOUTHEASTERLY WINDS 10 TO 20 KNOTS WITH SOME OCCASIONAL HIGHER GUSTS WILL BE THE RULE THROUGH 00Z FRIDAY. SCHNEIDER PREV DISCUSSION... /ISSUED 337 PM CDT WED JUN 13 2012/ DISCUSSION... THUNDERSTORMS ARE STARTING TO DEVELOP OVER THE MOUNTAINS IN NEW MEXICO. MEANWHILE...SCATTERED AND BROKEN CLOUD COVER OVER THE WESTERN TEXAS PANHANDLE HAS LIMITED THE HEATING WHERE THE HIGHEST INSTABILITY IS FORECAST TO BE FOR THIS EVENING. THIS EVENING...STILL SOME QUESTION ON THE CONVECTIVE POTENTIAL. MODELS...SPECIFICALLY THE NAM AND RAP...SHOW LARGE CAPE VALUES...1500 TO 3000 J/KG...AND MODEST SHEAR VALUES OF 20 TO 30 KT. HOWEVER...SUSPECT THAT THE CAP IS STILL IN PLACE...ESPECIALLY IN LOCATIONS THAT SAW CLOUD COVER MOST OF THE DAY. EARLIER RUNS OF THE RAP WERE SHOWING CONVECTIVE DEVELOPMENT NEAR KAMA...HOWEVER...EXPECT THAT THIS WAS OVER ESTIMATING THE AMOUNT OF LIFT ALONG THE NOW RATHER POORLY DEFINED SURFACE TROUGH. SO EXPECT THE MAIN AREA OF THUNDERSTORMS WILL ONCE AGAIN BE STORMS MOVING IN FROM NM. TOMORROW...MODELS INDICATE THE DRYLINE SHOULD SHIFT FURTHER EAST...WITH THE GFS EVEN SHOWING THE DRYLINE MOVING INTO THE FAR WESTERN PANHANDLES. WITH THE DRYLINE CURRENTLY SO FAR WEST...NOT CERTAIN THAT IT WILL BE ABLE TO PUSH THIS FAR EAST. WHEREVER IT STALLS...IT SHOULD BE THE MAIN FOCUS FOR THUNDERSTORM DEVELOPMENT TOMORROW. WITH EVEN WEAKER UPPER LEVEL STEERING FLOW TOMORROW...STORMS MAY NOT PROPAGATE VERY FAR FROM THE DRYLINE. FRIDAY THROUGH MONDAY...THE MAIN FOCUS THROUGH THIS PERIOD IS THE BROAD UPPER LEVEL TROUGH CURRENTLY OVER CA...EXPECTED TO DIG SOUTH THROUGH FRIDAY. HOWEVER THEN...BOTH THE GFS AND ECMWF SHOW THE TROUGH SLOWLY RETROGRESSING THROUGH THE WEEKEND AS A HIGH BUILDS IN OVER TX...AND THEN RETROGRESSES ITSELF. WHAT MAKES THIS PATTERN UNUSUAL IS THAT AT THE SAME TIME...THE MODEL SOLUTIONS SHOW A SLOW...BUT PROGRESSIVE...UPPER LEVEL TROUGH MOVING EAST ACROSS THE NORTHERN TIER OF THE U.S. THIS IS A BIG CHANGE FROM PREVIOUS RUNS OF MODELS...WHICH SHOWED THE BROAD TROUGH STAYING NEARLY STATIONARY AS A SERIES OF SHORT WAVE TROUGHS LIFT NE OVER THE SOUTHERN PLAINS...BRINGING ABUNDANT CHANCES FOR PRECIPITATION THROUGH THE WEEKEND. WITH THE NEW SOLUTION...THERE ARE RATHER LIMITED CHANCES FOR PRECIPITATION FOR THE REGION. TUESDAY...IN ANOTHER STARK CONTRAST FROM PREVIOUS FORECASTS...THERE IS NO HINT OF THE COLD FRONT MOVING THROUGH THE REGION TUESDAY. THIS SEEMS REASONABLE AS IT IS DIFFICULT THIS TIME OF YEAR TO GET STRONG COLD FRONTS THIS FAR SOUTH WITH OUT A SIGNIFICANT UPPER LEVEL LOW OR TROUGH. JOHNSON FIRE WEATHER... ABOVE NORMAL MOISTURE WILL REMAIN IN PLACE OVER THE NEXT SEVERAL DAYS...KEEPING RELATIVE HUMIDITY VALUES WELL ABOVE 20 PERCENT FOR MUCH OF THE REGION. THE ONE EXCEPTION IS TOMORROW...WHEN A WEAK DRYLINE COULD SNEAK INTO THE FAR WESTERN TEXAS PANHANDLE...RESULTING IN MINIMUM RELATIVE HUMIDITY VALUES NEAR 20 PERCENT...WITH SOUTHERLY WINDS OF 15 TO 20 MPH. HOWEVER...RECENT RAINS SHOULD PRECLUDE ANY ELEVATED FIRE WEATHER CONDITIONS FOR TOMORROW. JOHNSON && .AMA WATCHES/WARNINGS/ADVISORIES... TX...NONE. OK...NONE. && $$ 11/08
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
412 AM CDT THU JUN 14 2012 .SYNOPSIS..LOW-AMPLITUDE BAND OF WESTERLIES IN PLACE ACRS THE NRN TIER OF THE CONUS AND SRN CANADA...WITH MEAN TROF POSN OVER THE NRN ROCKIES AND RIDGE POSN IN THE E. THAT PATTERN WL PERSIST FOR A FEW DAYS...THEN THE WESTERLIES WL STRENGTHEN AND LARGE SCALE AMPLIFICATION WL OCCUR. BY EARLY NEXT WEEK...THERE SHOULD BE A BROAD BUT FAIRLY STG UPR TROF CENTERED OVER THE NRN ROCKIES OR NRN PLAINS...WITH A DOWNSTREAM RIDGE OVER THE ERN CONUS. THOUGH DAILY TEMPS WL VARY DUE TO CLOUD COVER WITH THE PASSAGE OF INDIVIDUAL SHRTWVS/FRONTAL SYSTEMS...TEMPS WL REMAIN ABV NORMAL FOR MUCH OF THE FCST PERIOD. A COOL DOWN IS POSSIBLE LATE IN THE PERIOD OR JUST BEYOND IF THE MEAN TROF AXIS EDGES E AS NOW INDICATED. THE PATTERN LOOKS MORE FAVORABLE FOR PCPN THAN WHAT WE/VE BEEN IN FOR THE PAST COUPLE WEEKS. OF COURSE...ACTUAL PCPN AMNTS WL DEPEND ON THE TRACK OF INDIVIDUAL CONVECTIVE SYSTEMS THAT REMAIN UNKNOW AT THIS POINT. && .SHORT TERM...TDA/TNGT/FRI. ISSUES WITH THE POTENTIAL FOR CONVECTION TO SPILL OVER INTO THE FCST AREA ARISE EARLY AND THEN CONT FOR THE REST OF THE PERIOD. PRETTY IMPRESSIVE TSTM COMPLEX OVER ERN ND/NERN SD. IT/S BEING FED BY INSTABILITY AXIS STILL WELL W OF THE FCST AREA. MOST OF THE GUIDANCE TAKES THE COMPLEX NE AND WEAKENS IT DURING THE DAY...THOUGH THE RUC BRINGS IT E THEN TURNS IT DUE S ACRS MN...DIRECTLY INTO THE LOW-LEVEL INFLOW. SOME MOISTURE CONVERGENCE NOTED ON LOCAL MESO PLOTS OVER SRN MN...AND RADAR TRENDS SEEM TO FIT THE RUC. GET THE FEELING THIS IS GOING TO BE ONE OF THOSE SITUATIONS WHERE IT/S A WASTE OF TIME TRYING TO TRY AND TRACK THE FEATURE USING THE GUIDANCE AND SIMPLY KEEPING AN EYE ON THE RADAR MOSAIC LOOP AND USING EXTRAPOLATION IS GOING TO WORK BETTER. AS SUCH...NEED TO KEEP POPS OVER THE WRN PART OF THE FCST AREA TDA...AND PROBABLY CAN/T BE TOO SPECIFIC WITH TIMING AS ONGOING STORMS COULD GET THERE BEFORE NOON IF THEY HOLD TOGETHER. OVERALL TREND HOWEVER HAS TO BE FOR STORMS TO WEAKEN SIGNIFICANTLY AS THEY GET FARTHER E...AND FOR THE POTENTIAL FOR RE-DEVELOPEMENT FARTHER E TO BE GREATLY LIMITED BY INFLUX OF DRY AIR CIRCULATION BACK OUT OF DEPARTING ANTICYCLONE. PRETTY MUCH THE SAME STORY FOR TONIGHT AND FRI. SHRA/TSRA WL GRADUALLY START TO EDGE E AS COLD FRONT TRAILING FM CYCLONE LIFTG TOWARD HUDSON BAY WORKS TOWARD THE RGN. BUT THE FRONT WL START TO SLOW AND WEAKEN AS IT GETS TO THE FCST AREA AS IT/S PARENT CYCLONE PULLS OFF TO THE NE. DRY AIR FM DEPARTING ANTICYCLONE WL CONT TO FEED DRY AIR INTO ERN WI. MAIN FCST CHG WITH THIS ISSUANCE WAS TO TRIM POPS OVER THE SERN PART OF THE FCST AREA. ALTHOUGH IT NOW LOOKS LIKE E-C WI WL STAY DRY THROUGH FRI...WAS NOT COMFORTABLE TOTALLY PULLING POPS OUT FOR MOST OF THAT AREA. SO BACKED DOWN FM WHAT WE HAD GOING...AND WL ALLOW LATER SHIFTS TO REMOVE IF CURRENT TRENDS CONTINUE. WARMER AIR WL BE RETURNING TO THE AREA ON SLY WINDS. THE BEST PERFORMING GUIDANCE WAS VERY WARM OVER E-C WI ON FRI...PROBABLY DUE TO A LACK OF PCPN. IT/S A TRICKY FCST...BECAUSE IF THERE ARE MORE CLDS WE WON/T WARM AS MUCH. STILL...TRENDING TOWARD A DRIER FCST SUGGESTED THE NEED TO GO WITH THE WARMER MAXES. .LONG TERM...FRIDAY NIGHT THROUGH NEXT THURSDAY. FORECAST CONFIDENCE LOW WITH CHALLENGING EXTENDED FORECAST. WILL BE DIFFICULT TO MAKE ANY NOTABLE ADJUSTMENTS TO PREVIOUS FORECAST AS MODEL CONCENSUS INDICATE SEVERAL DISTURBANCES...IN INITIALLY BAGGY WESTERN US TROUGH...WILL TRY AND RIDE UP THE WESTERN PERIPHERY OF STUBBORN MEAN RIDGE OVER THE EASTERN CONUS. MEDIUM RANGE MODELS OFFER A VARIETY OF SOLUTIONS WITH RESPECT TO TIMING AND INTENSITY OF EMBEDDED DISTURBANCES AS WELL AS DIFFER ON EVOLUTION OF DOWNSTREAM RIDGE. INHERITED AT LEAST CHANCE POPS EACH DAY OF THE EXTENDED AND SEE NO CLEAR SIGNAL IN THE LATEST SUITE OF MODEL RUNS TO JUSTIFY MAKING ANY SIGNIFICANT CHANGES. LATEST GEM DID SUGGEST THAT POSSIBLE MCS COMING OUT OF IOWA FRIDAY NIGHT WOULD NOT GET INTO THE SOUTHWEST PART OF WISCONSIN UNTIL AFTER 12Z SATURDAY AND WOULD AT BEST CLIP OUR SOUTHERN COUNTIES SATURDAY MORNING...WHILE OPER GFS WAS MUCH QUICKER AND FURTHER NORTH. ECMWF AND GEM SUGGESTED THERE COULD BE VERY LITTLE IN THE WAY OF PRECIPITATION IN THE FORECAST AREA FRIDAY NIGHT. DID TRIM BACK POPS SOME DURING THIS PERIOD...BUT REMAINED IN THE CHANCE CATEGORY OVER THE SOUTHWEST PORTION OF THE FORECAST AREA. ALSO LOWERED POPS SOME ON SUNDAY NIGHT AS IT APPEARS THERE COULD BE A BREAK IN PRECIPTATION BEHIND INITIAL DISTURBANCE. WILL LET LATER FORECAST SHIFTS TRY AND PROVIDE A BIT MORE RESOLUTION WITH LATER MODEL FORECASTS. PRETTY MUCH LEFT REMAINDER OF EXTENDED AS INHERITED AND RETAINED CHANCE POPS THROUGH NEXT WEDNESDAY WITH RATHER ACTIVE SOUTHWEST FLOW WITH SEVERAL DISTURBANCES FORECAST TO IMPACT THE WESTERN GREAT LAKES REGION. STUCK WITH MODEL BLEND FOR TEMPS AS TOO DIFFICULT TO RESOLVE TIMING OF INDIVIDUAL DISTURBANCES AND THEIR ASSOCIATED PRECIP AND CLOUD COVER. && .AVIATION...FOR 12Z TAF ISSUANCE. VFR CONDITIONS ACRS THE AREA ATTM...WITH JUST PASSING MIDDLE AND HIGH CLDS. AT THIS POINT DON/T PLAN TO INCLUDE EXPLICIT THUNDER AT ANY OF THE TAF SITES AS BEST CONVECTION SHOULD REMAIN FOCUSED W OF THE AREA. BUT WL TAKE ANOTHER LOOK AND MAKE FINAL DECISION AT ISSUANCE TIME. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SKOWRONSKI/ESB
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
320 AM CDT THU JUN 14 2012 .SHORT TERM...TONIGHT THROUGH FRIDAY NIGHT 320 AM CDT THU JUN 14 2012 MAIN CONCERN WILL BE SHOWER/THUNDERSTORM CHANCES THROUGH THE PERIOD. WATER VAPOR AND RAP ANALYSIS EARLY THIS MORNING SHOW A VIGOROUS MID-LEVEL TROUGH/CLOSED LOW OVER SOUTHERN SASKATCHEWAN...EXTENDING SOUTHWARD INTO EASTERN MT. ASSOCIATED SURFACE LOW WAS OVER WESTERN SD. MOISTURE TRANSPORT/LIFT AHEAD OF THE MID-LEVEL WAVE/SURFACE LOW WAS GENERATING AN MCS THAT WAS MOVING ACROSS EASTERN ND. MEANWHILE...ANOTHER WEAKENING MID-LEVEL WAVE WAS MOVING ACROSS IA. SHRA/TS HAVE DISSIPATED WITH THIS WAVE AS THE MAIN AXIS OF MOISTURE TRANSPORT FOCUSED INTO THE ND MCS. OTHERWISE...CLOSER TO HOME...A FEW MID-CLOUD AND ANVIL DEBRIS CLOUD FROM OLD IA CONVECTION DRIFTING ACROSS THE AREA WITH TEMPERATURES AT 3 AM RANGING FROM THE MIDDLE 50S TO LOWER 60S. WILL BE KEEPING CLOSE TRACK OF THE MCS THIS MORNING...WATCHING ITS EASTWARD PROGRESS. MODELS IN GOOD AGREEMENT...TAKING THE MID-LEVEL LOW/TROUGH FROM MT INTO NORTHEAST INTO SOUTHERN MANITOBA. THIS TAKES NOSE OF MOISTURE TRANSPORT NORTHEAST WITH IT...SO EXPECTING THE MCS TO SCOOT NORTHEAST AS WELL INTO NORTHERN MN. OUR AREA WILL REMAIN ON THE EASTERN PERIPHERY OF THIS MOISTURE TRANSPORT FOR SOME ACCAS GENERATION AND ISOLATED SHRA/TS ACTIVITY. THE MAJORITY OF THIS SHOULD REMAIN NORTHWEST OF A MEDFORD/ARCADIA/ROCHESTER/AUSTIN LINE. HIGH PRESSURE OVER THE GREAT LAKES/OHIO RIVER VALLEY REGION WILL LIKELY KEEP AREAS SOUTHEAST OF THIS LINE PARTLY/MOSTLY SUNNY. OTHERWISE...PLAN ON HIGHS IN THE UPPER 70S TO THE MIDDLE 80S. FOR LATER THIS AFTERNOON...EXPECTING A LINE OF THUNDERSTORMS TO ERUPT ALONG A COLD FRONT PUSHING EAST INTO CENTRAL MN AS 0-3 MUCAPE INCREASES TO AROUND 3000J/KG AND MLCAPE INTO THE 1000-1500J/KG RANGE. AMPLE SHEAR ALSO PRESENT IN THE 25-35KT RANGE. SO...THERE IS A GOOD CHANCE FOR THIS LINE TO BECOME SEVERE. AS THE COLD FRONT/LINE OF STORMS MOVES INTO THE AREA...EXPECTING A WEAKENING TREND AS CAPE DIMINISHES AND BEST SLUG OF MOISTURE TRANSPORT SKIRTS NORTH INTO NORTHERN MN. MAINTAINED MID-RANGE SHRA/TS CHANCES FRIDAY THROUGH FRIDAY NIGHT AS AREA WILL BE SUSCEPTIBLE TO WEAK EMBEDDED WAVES IN SOUTHWEST FLOW ALOFT INTERACTING WITH DISSIPATING FRONTAL BOUNDARY. LOOKING FOR HIGHS ON FRIDAY TO TOP OFF IN THE LOW/MID 80S. .LONG TERM...SATURDAY THROUGH WEDNESDAY 320 AM CDT THU JUN 14 2012 WILL HAVE TO WATCH SATURDAY/SATURDAY EVENING CLOSELY AS MODELS SHOW A VIGOROUS MID-LEVEL TROUGH AND SURFACE COLD FRONT DROPPING SOUTHEAST INTO THE REGION. SURPRISINGLY...BOTH THE GFS AND ECMWF ONLY PRODUCE AROUND 500-600J/KG 0-3KM MLCAPE AND THIS COULD BE TIED INTO CLOUD COVER. HOWEVER IF MORE HEATING IS REALIZED...THERE COULD BE BE A SHOT AT SEVERE WEATHER GIVEN STEEPENING LAPSE RATES AND DECENT BULK SHEAR. FOR SUNDAY...LOOKS LIKE MOST OF THE AREA WILL BE DRY WITH FRONT EXITING THE AREA AND A WEAK RIDGE OF HIGH PRESSURE BUILDING IN. REST OF THE PERIOD MARKED BY A FAIRLY PROGRESSIVE/HIGH ZONAL FLOW WITH EMBEDDED WAVES. MODEL CONSENSUS YIELDS MID-RANGE SHRA/THUNDER CHANCES FOR MONDAY THROUGH WEDNESDAY WHICH SEEMS REASONABLE GIVEN THE PATTERN. HIGH TEMPERATURES EXPECTED TO AT OR A COUPLE DEGREES ABOVE NORMAL IN THE MID 70S TO MID 80S. && .AVIATION...THROUGH 06Z FRIDAY 1141 PM CDT WED JUN 13 2012 SOUTHERLY FLOW WILL CONTINUE AT THE TAF SITES...WITH MAINLY VFR MID AND HIGH LEVEL CLOUDS EXPECTED THROUGH MUCH OF THE PERIOD. MOISTURE TRANSPORT SLOWLY EDGES INTO THE AREA ON THURSDAY WITH SOME INSTABILITIES DEVELOPING IN THE AFTERNOON...ESPECIALLY AT KRST. IN ADDITION THE PRESSURE GRADIENT TIGHTENS AND EXPECT WINDS TO GUST TO NEAR 22 KNOTS AT KLSE AND 28 KNOTS AT KRST DURING THE AFTERNOON. BEST CHANCE FOR ANY TYPE OF CONVECTION TO AFFECT THE TAF SITES WILL COME AFTER 02Z AT KLSE AND 20Z AT KRST. IF THIS CONVECTION DOES IMPACT THE TAF SITES...SOME CEILINGS COULD DROP INTO THE MVFR CATEGORY WITH ANY SHOWERS/STORMS. && .ARX WATCHES/WARNINGS/ADVISORIES... 320 AM CDT THU JUN 14 2012 WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...DAS LONG TERM...DAS AVIATION...RABERDING
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1141 PM CDT WED JUN 13 2012 .SHORT TERM...TONIGHT THROUGH FRIDAY NIGHT 356 PM CDT WED JUN 13 2012 AT 3 PM...A CONVECTIVELY INDUCED VORTICITY MAXIMUM WAS MOVING THROUGH NORTH-CENTRAL IOWA AND SOUTH-CENTRAL MINNESOTA. THE LAPS INDICATES MODERATE TO STRONG 800-600 MB FRONTOGENESIS ACROSS SOUTHEAST MINNESOTA AND NORTHEAST IOWA. THE LATEST RAP CONTINUES TO SHOW THAT THIS FRONTOGENESIS WILL CONTINUE TO WEAKEN LATE THIS AFTERNOON. AS THIS OCCURS...EXPECT THE BAND OF SHOWERS JUST TO OUR WEST WILL CONTINUE TO WEAKEN AND DISSIPATE. THIS IS IN GOOD AGREEMENT WITH THE HRRR...EAST ARW...AND EAST NMM. FOR TONIGHT...THE 13.12Z MODELS ARE IN GOOD AGREEMENT THAT STRONG 925 TO 700 MB MOISTURE TRANSPORT WILL DEVELOP ACROSS NORTHERN AND WESTERN MINNESOTA. THIS IS IN RESPONSE TO A WARM FRONT MOVING THROUGH THIS REGION. ALL OF THE MESO MODELS AND BROADER SCALE MODELS ARE IN FAIRLY GOOD AGREEMENT THAT A MAJORITY OF THE PRECIPITATION OVERNIGHT WILL BE WEST OF A CHARLES CITY IOWA TO DIAMOND LAKE WISCONSIN LINE. ON THURSDAY AFTERNOON AND EVENING...THE MODELS ARE SHOWING THAT THERE WILL INCREASING SHEAR ACROSS EASTERN MINNESOTA...AND NORTHERN WESTERN WISCONSIN AS A STRONG WAVE SHORT WAVE MOVES ACROSS NORTHERN MINNESOTA. BULK SHEARS CLIMB ABOVE 40 KNOTS ACROSS THE AFOREMENTIONED AREAS WHICH WILL MAKE IT FAVORABLE FOR THE DEVELOPMENT OF SUPERCELL THUNDERSTORMS. THE SIGNIFICANT TORNADO PARAMETER SUGGESTS THAT THERE WILL BE THE POTENTIAL OF TORNADOES. THE NAM/WRF WOULD SUGGEST EAST-CENTRAL MINNESOTA AND NORTHWEST WISCONSIN. MEANWHILE THE GFS INDICATES THAT THIS MAY BE A BIT FURTHER SOUTH AND IT WOULD INCLUDE SOUTHEAST MINNESOTA AND WEST- CENTRAL WISCONSIN. WHILE THE SHEAR IS GOOD...THERE IS SOME CONCERN THAT THAT DEW POINTS IN THE MODELS MAY BE A BIT TOO HIGH...AND IF THIS IS TRUE THAN THE CAPES MAY BE TOO HIGH TOO. THE TORNADO THREAT WOULD LIKELY IN THE MID TO LATE AFTERNOON...AND THEN EVOLVE INTO A WIND THREAT AS THE COLD POOLS COALESCE. BEYOND THIS TIME PERIOD...THERE IS A LOT OF UNCERTAINTY ON WHERE THE FRONT WILL BE LOCATED ACROSS THE REGION. DUE TO THIS...THERE IS LOW CONFIDENCE ON BOTH THE TEMPERATURE AND PRECIPITATION FORECAST. .LONG TERM...SATURDAY THROUGH WEDNESDAY 356 PM CDT WED JUN 13 2012 ON SATURDAY AND SATURDAY NIGHT...THE MODELS SUGGEST THAT A COLD FRONT AND UPPER LEVEL TROUGH WILL BE MOVING THROUGH THE REGION. THE BULK SHEAR WILL ONCE AGAIN CLIMB ABOVE 40 KNOTS. THIS WOULD BE CONDUCIVE FOR THE DEVELOPMENT OF SUPERCELL THUNDERSTORMS. HOWEVER THERE IS QUITE A BIT OF UNCERTAINTY ON WHEN THE COLD FRONT WILL MOVE THROUGH THE REGION AND HOW MUCH INSTABILITY WILL BE AHEAD OF IT. ON SUNDAY AND SUNDAY NIGHT...BOTH THE GEM AND ECMWF INDICATE THAT THE AREA MAY BE DRY AS HIGH PRESSURE BUILDS ACROSS THE REGION. MEANWHILE THE GFS IS SHOWING YET ANOTHER FRONT MOVING INTO THE REGION. DUE TO THIS THE ALL BLEND POPS WERE REDUCED SOME. LOOKING TOWARD THE MIDDLE OF NEXT WEEK...THERE LOOKS TO BE A PATTERN CHANGE BACK TO NORTHWEST FLOW AS A TROUGH BUILDS ACROSS THE REGION. THE GFS IS NOT AS AGGRESSIVE AS THE ECMWF. HOWEVER LOOKING WITH A MADDEN JULIAN OSCILLATION MOVING FROM PHASE 6 TO 7...THE ECMWF WOULD BE THE MOST PROBABLE OUTCOME. && .AVIATION...THROUGH 06Z FRIDAY 1141 PM CDT WED JUN 13 2012 SOUTHERLY FLOW WILL CONTINUE AT THE TAF SITES...WITH MAINLY VFR MID AND HIGH LEVEL CLOUDS EXPECTED THROUGH MUCH OF THE PERIOD. MOISTURE TRANSPORT SLOWLY EDGES INTO THE AREA ON THURSDAY WITH SOME INSTABILITIES DEVELOPING IN THE AFTERNOON...ESPECIALLY AT KRST. IN ADDITION THE PRESSURE GRADIENT TIGHTENS AND EXPECT WINDS TO GUST TO NEAR 22 KNOTS AT KLSE AND 28 KNOTS AT KRST DURING THE AFTERNOON. BEST CHANCE FOR ANY TYPE OF CONVECTION TO AFFECT THE TAF SITES WILL COME AFTER 02Z AT KLSE AND 20Z AT KRST. IF THIS CONVECTION DOES IMPACT THE TAF SITES...SOME CEILINGS COULD DROP INTO THE MVFR CATEGORY WITH ANY SHOWERS/STORMS. && .ARX WATCHES/WARNINGS/ADVISORIES... 356 PM CDT WED JUN 13 2012 WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...BOYNE LONG TERM...BOYNE AVIATION...RABERDING
AREA FORECAST DISCUSSION
NWS MIAMI FL
941 AM EDT THU JUN 14 2012 .UPDATE... THE 12Z SOUNDING SHOWED MOISTURE HAD INCREASED A LITTLE SINCE THIS TIME YESTERDAY...ALTHOUGH STILL BELOW NORMAL. WITH DECENT MID LEVEL LAPSE RATES...SOME STORMS COULD BE STRONG THIS AFTERNOON WITH THE MAIN THREAT BEGIN WINDS UP TO 50 MPH AND SMALL HAIL. THE HRRR AND LOCAL WRF BOTH SHOW ONLY ISOLATED STORMS ALONG THE SEA BREEZE BOUNDARIES THROUGH THE MID AFTERNOON...AS THE BEST MOISTURE REMAINS POOLED ALONG THE BOUNDARY IN NORTH CENTRAL FLORIDA. HOWEVER...SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP NEAR OR NORTH OF THE LAKE LATE THIS AFTERNOON AND THEN PUSH EAST TO SOUTHEAST ONCE AGAIN THROUGH THE EVENING HOURS. SO BUMPED UP POPS TO CHANCE FOR TONIGHT ACROSS PALM BEACH AND BROWARD COUNTIES. OTHERWISE...IT WILL BE WARM AND PARTLY CLOUDY TODAY. && .PREV DISCUSSION... /ISSUED 722 AM EDT THU JUN 14 2012/ AVIATION... VFR/LIGHT WINDS WILL PREVAIL. WINDS WILL BECOME ONSHORE 5-10 KT BY MID AFTERNOON ALONG WITH ISD-SCT TSRA DEVELOPING...AND FOCUSED INTERIOR/EAST SO MAINTAINED VCTS EAST COAST TERMINALS 18-00Z. PREV DISCUSSION... /ISSUED 357 AM EDT THU JUN 14 2012/ DISCUSSION...AFTER SOME LATE EVENING CONVECTION OVER PALM BEACH AND BROWARD COUNTIES, WHICH DIMINISHED AROUND 04Z, SKIES HAVE BECOME MOSTLY CLEAR TO PARTLY CLOUDY ACROSS THE REGION. A BIT OF PATCHY FOG COULD DEVELOP IN A FEW AREAS ACROSS THE INTERIOR AND LAKE REGION EARLY THIS MORNING, BUT POTENTIAL IS LOW. OTHERWISE, THE DAY WILL BEGIN TRANQUIL AND WARM ACROSS MUCH OF THE REGION. A MID LEVEL TROUGH AXIS AND ASSOCIATED SURFACE FRONTAL BOUNDARY WILL MOVE INTO CENTRAL FLORIDA TODAY. THE MAJORITY OF THE GUIDANCE STILL KEEPS THE DEEPEST MOISTURE NORTH OF THE LOCAL AREA, ALTHOUGH PRECIPITABLE WATERS RISE TO AROUND 1.7-1.8 INCHES ACROSS MUCH OF THE REGION. AS SEA BREEZE BOUNDARIES ADVANCE INLAND AND AT LEAST ONE SUBTLE VORT MAX APPROACHES, ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED BY AFTERNOON, WITH THE HIGHEST CHANCE (40 PERCENT) OVER THE LAKE REGION AND NORTHEAST SECTIONS OF THE CWA. THE LATEST HRRR DOES SHOW SOME CONVECTION DEVELOPING OVER THE MAINLAND AS EARLY AS 15Z, WHILE AN ORGANIZED LINE OF SHOWERS/STORMS DEVELOPS OVER CENTRAL FLORIDA AROUND 18Z AND PUSHES SOUTHEAST. A FEW STORMS COULD BECOME QUITE STRONG LATER THIS AFTERNOON AND EVENING WITH POTENTIALLY STRONG WIND GUSTS AND SMALL HAIL. AS LOW PRESSURE REMAINS EAST OF FLORIDA ON FRIDAY AND THE REMNANTS OF THE FRONTAL TROUGH APPROACH THE AREA, THE FORECAST MODELS INDICATE A SURGE IN MOISTURE, HEALTHIER LOW LEVEL CONVERGENCE, AND INCREASED INSTABILITY, ESPECIALLY AFTER 18Z. WE WILL CARRY LOW CHANCE POPS (30 PERCENT) FOR MUCH OF THE REGION FRIDAY AFTERNOON. THE REMNANTS OF THE FRONT WILL SLOWLY PASS THROUGH FRIDAY NIGHT INTO SATURDAY EVENING, WITH GRADUALLY IMPROVING CONDITIONS FROM NORTHEAST TO SOUTHWEST. 20-30 POPS ARE STILL WARRANTED THROUGH THE WEEKEND, ALTHOUGH DRIER AIR WILL LIMIT INSTABILITY AS THE LOW LEVEL FLOW BECOMES NORTHEASTERLY. THE PRESSURE GRADIENT WILL ALSO TIGHTEN DURING THIS PERIOD, RESULTING IN BREEZY CONDITIONS AS A BROAD TROUGH LINGERS OFF THE EASTERN SEABOARD AND HIGH PRESSURE MOVES INTO THE SOUTHEAST STATES. MARINE SHOWERS WILL REMAIN POSSIBLE THROUGH SUNDAY WITH SOME ALSO AFFECTING THE EAST COAST, PARTICULARLY AT NIGHT AS COASTAL CONVERGENCE INCREASES. A MID LEVEL TROUGH ALONG THE U.S. EAST COAST WILL KEEP ANY DEEP TROPICAL MOISTURE TO OUR SOUTH AND EAST MONDAY INTO TUESDAY. HOWEVER, INDICATIONS ARE THAT SOME MOISTURE MAY START SURGING NORTHWEST INTO SOUTH FLORIDA BY NEXT WEDNESDAY. AVIATION...06Z ISSUANCE...VFR/LIGHT WINDS WILL PREVAIL. WINDS WILL BECOME ONSHORE 5-10 KT BY MID AFTERNOON ALONG WITH ISD-SCT TSRA DEVELOPING...AND FOCUSED INTERIOR/EAST SO INCLUDED VCTS EAST COAST TERMINALS 18-00Z. /GREGORIA MARINE...A RIDGE OF HIGH PRESSURE WILL MOVE SLOWLY SOUTH OF THE AREA TODAY. A WEAK PRESSURE GRADIENT WILL REMAIN IN PLACE THROUGH EARLY FRIDAY WITH WINDS 15 KNOTS OR LESS AND SEAS OF 2 TO 4 FEET. WIND SPEEDS WILL BE A BIT STRONGER FRIDAY NIGHT THROUGH SUNDAY. IN ADDITION, A NORTHEAST SWELL OF 2 TO 3 FEET MAY AFFECT PORTIONS OF THE ATLANTIC WATERS THIS WEEKEND. OTHERWISE, ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TODAY THROUGH SATURDAY. FIRE WEATHER...NO SIGNIFICANT CONCERNS AS RELATIVE HUMIDITIES WILL REMAIN ABOVE CRITICAL VALUES OVER AT LEAST THE NEXT FEW DAYS. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 90 75 87 74 / 40 40 30 20 FORT LAUDERDALE 91 76 89 75 / 30 20 30 30 MIAMI 92 76 90 75 / 20 20 30 30 NAPLES 90 75 90 73 / 20 10 30 30 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$ DISCUSSION/MARINE/FIRE...84/AK AVIATION/RADAR...85/AG
AREA FORECAST DISCUSSION
NWS MIAMI FL
722 AM EDT THU JUN 14 2012 .AVIATION... VFR/LIGHT WINDS WILL PREVAIL. WINDS WILL BECOME ONSHORE 5-10 KT BY MID AFTERNOON ALONG WITH ISD-SCT TSRA DEVELOPING...AND FOCUSED INTERIOR/EAST SO MAINTAINED VCTS EAST COAST TERMINALS 18-00Z. && .PREV DISCUSSION... /ISSUED 357 AM EDT THU JUN 14 2012/ DISCUSSION...AFTER SOME LATE EVENING CONVECTION OVER PALM BEACH AND BROWARD COUNTIES, WHICH DIMINISHED AROUND 04Z, SKIES HAVE BECOME MOSTLY CLEAR TO PARTLY CLOUDY ACROSS THE REGION. A BIT OF PATCHY FOG COULD DEVELOP IN A FEW AREAS ACROSS THE INTERIOR AND LAKE REGION EARLY THIS MORNING, BUT POTENTIAL IS LOW. OTHERWISE, THE DAY WILL BEGIN TRANQUIL AND WARM ACROSS MUCH OF THE REGION. A MID LEVEL TROUGH AXIS AND ASSOCIATED SURFACE FRONTAL BOUNDARY WILL MOVE INTO CENTRAL FLORIDA TODAY. THE MAJORITY OF THE GUIDANCE STILL KEEPS THE DEEPEST MOISTURE NORTH OF THE LOCAL AREA, ALTHOUGH PRECIPITABLE WATERS RISE TO AROUND 1.7-1.8 INCHES ACROSS MUCH OF THE REGION. AS SEA BREEZE BOUNDARIES ADVANCE INLAND AND AT LEAST ONE SUBTLE VORT MAX APPROACHES, ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED BY AFTERNOON, WITH THE HIGHEST CHANCE (40 PERCENT) OVER THE LAKE REGION AND NORTHEAST SECTIONS OF THE CWA. THE LATEST HRRR DOES SHOW SOME CONVECTION DEVELOPING OVER THE MAINLAND AS EARLY AS 15Z, WHILE AN ORGANIZED LINE OF SHOWERS/STORMS DEVELOPS OVER CENTRAL FLORIDA AROUND 18Z AND PUSHES SOUTHEAST. A FEW STORMS COULD BECOME QUITE STRONG LATER THIS AFTERNOON AND EVENING WITH POTENTIALLY STRONG WIND GUSTS AND SMALL HAIL. AS LOW PRESSURE REMAINS EAST OF FLORIDA ON FRIDAY AND THE REMNANTS OF THE FRONTAL TROUGH APPROACH THE AREA, THE FORECAST MODELS INDICATE A SURGE IN MOISTURE, HEALTHIER LOW LEVEL CONVERGENCE, AND INCREASED INSTABILITY, ESPECIALLY AFTER 18Z. WE WILL CARRY LOW CHANCE POPS (30 PERCENT) FOR MUCH OF THE REGION FRIDAY AFTERNOON. THE REMNANTS OF THE FRONT WILL SLOWLY PASS THROUGH FRIDAY NIGHT INTO SATURDAY EVENING, WITH GRADUALLY IMPROVING CONDITIONS FROM NORTHEAST TO SOUTHWEST. 20-30 POPS ARE STILL WARRANTED THROUGH THE WEEKEND, ALTHOUGH DRIER AIR WILL LIMIT INSTABILITY AS THE LOW LEVEL FLOW BECOMES NORTHEASTERLY. THE PRESSURE GRADIENT WILL ALSO TIGHTEN DURING THIS PERIOD, RESULTING IN BREEZY CONDITIONS AS A BROAD TROUGH LINGERS OFF THE EASTERN SEABOARD AND HIGH PRESSURE MOVES INTO THE SOUTHEAST STATES. MARINE SHOWERS WILL REMAIN POSSIBLE THROUGH SUNDAY WITH SOME ALSO AFFECTING THE EAST COAST, PARTICULARLY AT NIGHT AS COASTAL CONVERGENCE INCREASES. A MID LEVEL TROUGH ALONG THE U.S. EAST COAST WILL KEEP ANY DEEP TROPICAL MOISTURE TO OUR SOUTH AND EAST MONDAY INTO TUESDAY. HOWEVER, INDICATIONS ARE THAT SOME MOISTURE MAY START SURGING NORTHWEST INTO SOUTH FLORIDA BY NEXT WEDNESDAY. AVIATION...06Z ISSUANCE...VFR/LIGHT WINDS WILL PREVAIL. WINDS WILL BECOME ONSHORE 5-10 KT BY MID AFTERNOON ALONG WITH ISD-SCT TSRA DEVELOPING...AND FOCUSED INTERIOR/EAST SO INCLUDED VCTS EAST COAST TERMINALS 18-00Z. /GREGORIA MARINE...A RIDGE OF HIGH PRESSURE WILL MOVE SLOWLY SOUTH OF THE AREA TODAY. A WEAK PRESSURE GRADIENT WILL REMAIN IN PLACE THROUGH EARLY FRIDAY WITH WINDS 15 KNOTS OR LESS AND SEAS OF 2 TO 4 FEET. WIND SPEEDS WILL BE A BIT STRONGER FRIDAY NIGHT THROUGH SUNDAY. IN ADDITION, A NORTHEAST SWELL OF 2 TO 3 FEET MAY AFFECT PORTIONS OF THE ATLANTIC WATERS THIS WEEKEND. OTHERWISE, ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TODAY THROUGH SATURDAY. FIRE WEATHER...NO SIGNIFICANT CONCERNS AS RELATIVE HUMIDITIES WILL REMAIN ABOVE CRITICAL VALUES OVER AT LEAST THE NEXT FEW DAYS. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 90 75 87 74 / 40 20 30 20 FORT LAUDERDALE 91 76 89 75 / 30 20 30 30 MIAMI 92 76 90 75 / 20 20 30 30 NAPLES 90 75 90 73 / 20 10 30 30 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$ DISCUSSION/MARINE/FIRE...84/AK AVIATION/RADAR...85/AG
AREA FORECAST DISCUSSION
NWS HASTINGS NE
638 AM CDT THU JUN 14 2012 .AVIATION...12Z TAF. THE MAIN CONCERN WILL BE THUNDERSTORMS FOR THIS AFTERNOON AND EVENING. A COLD FRONT WILL BE APPROACHING THE KGRI TERMINAL AREA. ALONG THE FRONT THERE WILL BE A CHANCE FOR THUNDERSTORMS MAINLY DURING THE AFTERNOON AND EVENING HOURS. && .PREV DISCUSSION... /ISSUED 329 AM CDT THU JUN 14 2012/ SHORT TERM...TODAY THROUGH SATURDAY NIGHT. THE MAIN PROBLEM FOR THE SHORT TERM PERIOD WILL FOCUS ON THE NUMEROUS THUNDERSTORM CHANCES ALONG FRONTAL BOUNDARIES PUSHING THROUGH THE REGION. UPPER LEVEL ANALYSIS REVEALS MOSTLY ZONAL FLOW ACROSS THE CONUS...HOWEVER...A DEEPENING TROUGH ACROSS WESTERN CANADA AND NUMEROUS SHORT WAVES ARE EXPECTED TO EFFECT THE CENTRAL PLAINS THROUGH THE PERIOD. IN THE MID LEVELS...THE TROUGH APPEARS TO DEEPEN SOME...WHILE SURFACE LOW PRESSURE MOVES ACROSS THE FRONT RANGE OF THE ROCKIES INTO WESTERN NEBRASKA AND SOUTHERN SOUTH DAKOTA. A COOL FRONTAL BOUNDARY ALONG THE WESTERN PANHANDLE CAN BE SEEN WITH A WIND SHIFT IN THE OBSERVATIONS AND ALSO ON RADAR WITH A FEW LIGHT SHOWERS PUSHING OFF THE BOUNDARY IN THE PANHANDLE. THROUGHOUT THE DAY TODAY...THIS FRONTAL BOUNDARY WILL CONTINUE TO SLIDE EASTWARD ALONG THE PLAINS...WHILE THE MAIN PARENT UPPER LEVEL LOW PUSHES EASTWARD WELL NORTH OF THE PLAINS. WITH THE FRONT BEING THE MAIN FORCING MECHANISM...THE MODELS TRY TO GENERATE A FEW SHOWERS ACROSS WESTERN NEBRASKA THIS MORNING...AS THE FRONT ENCOUNTERS MORE MOIST AIR AND SLIGHTLY HIGHER DEWPOINTS. INITIAL THINKING IS MORE LIKE THE HRRR SOLUTION...IN WHICH SHOWERS DEVELOP ACROSS NORTHERN NEBRASKA THIS MORNING 12Z TO 15Z TIME FRAME BEFORE UNZIPPING SOUTHWEST ACROSS THE NORTHWEST PORTION OF THE FORECAST AREA DURING THE 15Z TO 18Z TIME FRAME. BY 18Z...INSTABILITY VALUES ARE QUITE HIGH WITH NEARLY 2500 TO 4000 J/KG EXPECTED DEPENDING ON THE MODEL. DEEP LAYER BULK SHEAR IS MINIMAL AT BEST...BUT COULD SEE SOME STRONG TO MARGINALLY SEVERE THUNDERSTORMS. AS THE FRONT CONTINUES TO SAG SOUTHEAST ACROSS THE FORECAST AREA DURING THE EVENING AND OVERNIGHT HOURS...THREAT AND PRECIPITATION CHANCES ALSO SHIFT SOUTHEAST. AGAIN THE NOSE OF THE LOW LEVEL JET NOSES IN ACROSS THE SOUTHEAST WHICH COULD HELP CONTINUE CONVECTION INTO THE OVERNIGHT HOURS ACROSS THE SOUTHEAST. FOR THE FRIDAY TIME FRAME...THE MAIN THINKING IS THAT WITH THE EXCEPTION OF THE FAR SOUTH AND SOUTHEAST WHERE THE FRONT REMAINS STALLED...MOST LOCATIONS WILL BE DRY. HOWEVER...THAT BEING SAID...WITH A FEW MODELS SUGGESTING GOOD SOUTHERLY FLOW IN THE MID LEVELS...COULD SEE SOME OVERRUNNING OF THE FRONTAL BOUNDARY WHICH COULD GENERATE SOME SHOWERS TO THE NORTH OF THE FRONT. AT THIS POINT...DECIDED TO LEAVE CHANCES ACROSS THE SOUTH AND SOUTHEAST...AND SLIGHTS ACROSS THE NORTHWEST FOR THAT POSSIBILITY. BY FRIDAY NIGHT...THE FRONT IS EXPECTED TO LIFT NORTHWARD...AND WITH THE DEVELOPMENT OF THE LOW LEVEL JET...EXPECTING THE POSSIBILITY OF MORE WIDESPREAD PRECIPITATION CHANCES TO THE NORTH OF THE BOUNDARY. ANOTHER UPPER LEVEL SHORT WAVE...SURFACE FRONTAL BOUNDARY COMBINATION IS ALSO IN THE WORKS TO MOVE THROUGH SATURDAY MORNING...BRINGING YET ANOTHER CHANCE SHOWERS AND THUNDERSTORMS. MODELS REMAIN INCONSISTENT HOWEVER...WITH TIMING AND PLACEMENT OF THIS NEXT SYSTEM. THAT BEING SAID...SATURDAY COULD BE AN INTERESTING REGARDING SEVERE WEATHER CHANCES INSTABILITY VALUES AHEAD OF THE FRONT ARE EXPECTED TO RANGE NEAR 2500 TO 4000 J/KG DEPENDING ON THE MODEL. ALSO...DEEP LAYER BULK SHEAR APPEARS TO BE A BIT BETTER AHEAD OF THE BOUNDARY...WITH A FEW MODELS HINTING AT NEAR 30 KTS. MADE VERY FEW CHANGES TO TEMPERATURES IN THE SHORT TERM PERIOD. DECIDED TO LOWER LOW TEMPERATURES A BIT ACROSS THE NORTHWEST ON SATURDAY EVENING BEHIND THE FRONTAL BOUNDARY. LONG TERM...12Z SUNDAY THROUGH WEDNESDAY. MAIN FORECAST CONCERNS WILL BE CHANCES FOR INTERMITTENT THUNDERSTORMS MONDAY NIGHT THROUGH WEDNESDAY AND TEMPERATURES. AN ACTIVE PATTERN CONTINUES ACROSS THE REGION THROUGH THE PERIOD. THERE ARE SEVERAL WAVES THAT MOVE THROUGH THE FORECAST AREA AND EACH OF THEM HAVE A SMALL POTENTIAL FOR SOME THUNDERSTORMS. WITHOUT A BOUNDARY THOUGH THEY SHOULD HAVE SOME DIFFICULTY CAUSING THUNDERSTORMS. THERE ARE SOME SLIGHT DIFFERENCES IN THE MODELS AND HOW STRONG THE UPPER LEVEL WAVES THAT MOVE THROUGH ARE. THE GFS IS STRONGER THAN THE ECMWF AND THEREFORE HAS MORE PRECIPITATION ACROSS THE AREA. FOR SUNDAY THROUGH MONDAY THERE IS A SURFACE LOW AND COLD FRONT DEVELOPING ON THE HIGH PLAINS AND IT STARTS TO MOVE THROUGH THE AREA MONDAY. WILL KEEP THIS PERIOD DRY. TEMPERATURES WILL BE WARM WITH HIGHS IN THE UPPER 80S TO MID 90S FOR HIGHS AND LOWS AROUND 70. THE FRONT WASHES OUT AS ANOTHER LOW DEVELOPS ON THE HIGH PLAINS MONDAY NIGHT. THE FRONT FINALLY MOVES THROUGH THE FORECAST AREA TUESDAY NIGHT...BUT IT STALLS JUST TO THE SOUTHEAST OF THE FORECAST AREA BY WEDNESDAY. WITH THE FRONT MOVING INTO THE NORTH WILL HAVE A CHANCE FOR THUNDERSTORMS IN THE NEBRASKA PART OF THE FORECAST AREA WITH THE STRONGER UPPER LEVEL WAVE IN THE NORTH. THE FRONT MOVES THROUGH THE AREA ON TUESDAY AND THUNDERSTORMS DEVELOP ALONG THE FRONT TUESDAY EVENING AND OVERNIGHT. THE THUNDERSTORMS WILL LINGER INTO WEDNESDAY IN THE SOUTHEAST AS THE FRONT STALLS AND THE MAIN UPPER LEVEL TROUGH MOVES TO THE EAST OF THE AREA. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
609 AM CDT THU JUN 14 2012 .AVIATION...12Z TAFS FOR KOMA...KLNK AND KOFK. CONVECTIVE TRENDS WILL BE THE PRIMARY CONCERN AT ALL THREE TAF SITES AS A COLD FRONT PUSHES INTO THE AREA...AND THEN EVENTUALLY STALLS. UNTIL STORMS ARRIVE...VFR CONDITIONS EXPECTED WITH SCATTERED TO BROKEN CIRRUS AND SOUTHERLY WINDS SUSTAINED AROUND 14-17ZKTS WITH GUSTS UP TO 24-27KTS. FIRST STORMS MAY IMPACT KOFK AS SOON AS ABOUT 17Z WITH THE STRONGEST STORMS EXPECTED FROM 19-23Z. FIRST STORM THREAT AT KOMA/KLNK BY ABOUT 21Z...THAT COULD LINGER THROUGH ABOUT 15/06Z. && .PREV DISCUSSION... /ISSUED 407 AM CDT THU JUN 14 2012/ DISCUSSION... MODELS HAVE BACKED OFF ADVERTISING FLOW BECOMING SOMEWHAT BLOCKED WITH A TROF DIGGING OVER THE WRN CONUS AND RIDGE AMPLIFYING EAST. SOLUTIONS NOW SHOWING A CUTOFF LOW FORMING OVER THE SWRN STATES BY SATURDAY MORNING WITH FAST FLOW WESTERLIES PREVAILING ACROSS THE NRN TIER STATES. FOR TODAY...SHORTWAVE TROF AND ATTENDANT SFC LOW MOVING ACROSS THE U.S./CAN BORDER WILL DRAG A COLD FRONT ACROSS THE NRN/CNTRL PLAINS AND BE THE FOCUS FOR NEXT ROUND OF THUNDERSTORM ACTIVITY. STRONG LLVL MOISTURE ADVECTION INTO THE REGION PUSH PRECIP WATER VALUES GREATER THAT 1.5"/KI AROUND 40...AND WITH DAYTIME HEATING MUCAPES CATAPULT TO 4500 J/KG. LATEST HIRES RAP AND NMM ARE ADVERTISING ACTIVITY ERUPTING AROUND 18Z ON EDGE OF WEAK CAP...JUST ON THE WRN PERIPHERY OF THE CWA. EXPECT CONVECTION WILL MORE OR LESS CONTINUE ALONG WELL DEFINE BNDRY LYR MOISTURE CONVG ZONE WELL INTO TONIGHT AND FRIDAY. BY FRIDAY NIGHT...ANOTHER SHORTWAVE TRAVERSING THE U.S./CAN BORDER WILL DRAG A COLD FRONT INTO THE CNTRL PLAINS. SMALL POPS ARE ALREADY IN PLACE THRU SUNDAY FOR THIS SO NO NEED FOR ADJUSTMENTS. OTHERWISE...APPEARS THAT SUBSEQUENT SHORTWAVES AND ATTENDANT SFC BOUNDARIES WILL KEEP AN UNSETTLED PATTERN IN PLACE THRU EARLY NEXT WEEK. DEE && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
847 AM EDT THU JUN 14 2012 .SYNOPSIS... HIGH PRESSURE IS IN CONTROL ACROSS THE EASTERN UNITED STATES. SEVERAL DAYS OF FAIR WEATHER WILL BE THE RESULT, WITH TEMPERATURES SLOWLY RISING THROUGH THE WEEKEND INTO NEXT WEEK. && .NEAR TERM /THROUGH TONIGHT/... 845 AM UPDATE... FCST WELL ON TRACK THIS MORNING...JUST A FEW MINOR ADJUSTMENTS NEEDED BASED ON LATEST TEMP DEWPOINT TRENDS. REGIONAL VIS SATELLITE IMAGERY SHOWING EARLY MORNING VALLEY FOG QUICKLY BURNING OFF WITH JUST SOME HIGH CI MOVING OVERHEAD. EXPECT CI TO CONTINUE FILTERING INTO THE REGION THIS MORNING ALL IN RESPONSE TO A WEAK SHORTWAVE MOVING THROUGH THE OHIO VALLEY. CLOSER TO THE SURFACE...SURFACE RIDGING EXTENDING SOUTH FROM PARENT HIGH PRESSURE OVER WESTERN QUEBEC WILL ENSURE A BEAUTIFUL DAY WITH HIGH TEMPS REACHING INTO THE LOWER TO MIDDLE 70S REGION WIDE. NO OTHER CHANGES NEEDED AT THIS TIME. PREVIOUS NEAR TERM DISCUSSION... PER THE CURRENT AVIATION DISCUSSION, WE ARE NOT FORECASTING MUCH FOG THIS MORNING. THERE IS TOO MUCH MIXING TO ALLOW THE ATMOSPHERE TO OVERCOME THE DRY/COLD AIR ADVECTION INSIDE THE BOUNDARY LAYER. SPOTTY LIGHT FOG WILL EXIST MAINLY EAST OF I-81 IN THE HIGHER MOISTURE. TEMPERATURES WILL BE BATTLING SOME LOW LEVEL COOL ADVECTION EARLY TODAY. WE ARE FORECASTING MAXES ON THE LOW SIDE OF GUIDANCE, AS MIX DOWN TEMPS ARE CONSIDERABLY COOLER THAN MOS. BETTER CHANCE FOR FOG FRIDAY MORNING AS MIXING WINDS WILL BE LIGHT, AND DRY ADVECTION WILL HAVE CEASED. FORECASTING PATCHY FOG MAINLY ALONG THE RIVER VALLEYS. && .SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... 330 AM UPDATE... SURFACE RIDGE OF HIGH PRESSURE WILL BE SPRAWLED OVER THE NORTHEAST AND MID ATLANTIC REGIONS DURING THE SHORT TERM PERIOD. HOWEVER...ALOFT...THE UPPER RIDGE AXIS WILL ONLY SLOWLY SHIFT FROM THE WESTERN TO CENTRAL GREAT LAKES. 1000-500MB THICKNESSES WILL ONLY EDGE UP SLIGHTLY. DRY ATMOSPHERE WITH A GOOD AMOUNT OF SUN WILL HELP DAYTIME HIGHS TO REACH SLIGHTLY ABOVE NORMAL. A LITTLE WRINKLE HAS SHOWN UP IN THE 00Z GFS RUN...IN THE FORM OF LIGHT QPF IN THE WESTERN ZONES SATURDAY AFTERNOON. GFS SOUNDINGS SHOW MARGINAL INSTABILITY AND PRECIPITABLE WATER AROUND AN INCH OR SO AT THAT TIME. MEANWHILE...NAM/ECMWF/GEM ARE RAIN FREE...YET THE NAM ALSO CLEARLY SHOWS THE REMAINS OF A WAVE DROPPING DOWN SOUTHWARD ON THE FRONT SIDE OF THE UPPER RIDGE...AS CAN BE SEEN VIA 500MB VORTICITY FIELD. MAJORITY OF MODELS AND ALL MOS NUMBERS SUGGEST KEEPING THINGS DRY. HIGH PRESSURE AT THE SURFACE AND ALOFT...WITH FAIRLY DRY ATMOSPHERE...SHOULD INHIBIT SHOWER DEVELOPMENT...OR AT LEAST CAUSE ENTRAINMENT ANY THAT TRY TO DEVELOP. GIVEN ALL OF THE ABOVE...A SINGLE GFS RUN COMPARED TO OTHER RUNS AND MODELS IS NOT ENOUGH FOR ME TO PLACE ANY MENTIONABLE POPS IN THE FORECAST FOR SATURDAY AT THIS TIME. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... 330 AM UPDATE... MODELS HAVE TRENDED TO A MORE GRADUAL PACE ON SETTING UP OF THE WARM RIDGE EARLY NEXT WEEK. STILL EXPECTING TEMPERATURES TO SWOON ABOVE NORMAL...IT WILL JUST TAKE LONGER FOR THE RIDGE AXIS TO FOLD OVER OUR REGION. FORECAST UPDATED ACCORDINGLY...BACKING OFF SLIGHTLY ON HOW QUICKLY THE WARMING IS EXPECTED TO OCCUR. EXPECTING WARMEST TEMPERATURES BY MIDWEEK...WITH MID 80S TO NEAR 90 CURRENTLY FIGURED FOR NEXT WEDNESDAY. PREVIOUS DISCUSSION... A VERY QUIET AND WARM PERIOD EXPECTED THROUGH THE EXTENDED TIME FRAME AS UPPER- LEVEL RIDGING CONTINUES TO DEVELOP ALONG THE EASTERN SEABOARD. AS THIS OCCURS...DISTURBANCES TRAVELING ACROSS THE NORTHERN PLAINS AND NORTHERN MISSISSIPPI VALLEY WILL BE DEFECTED NORTH OF THE REGION WHICH SHOULD KEEP OUR REGION DRY THROUGH AT LEAST TUESDAY. CORRESPONDING WITH THE INCREASE IN BUILDING HEIGHTS ALOFT...850 MB TEMPS ARE ALSO FORECAST TO INCREASE TO NEAR 20C BY TUE...WHICH WILL SUPPORT HIGH TEMPS REACHING INTO THE UPPER 80S TO POSSIBLY LOWER 90S BY EARLY NEXT WEEK. FCST UNCERTAINTY INCREASES TOWARDS THE CONCLUSION OF THE PERIOD AS THE NEWLY ARRIVING 12Z ECMWF SHOWS A GRADUAL BREAKDOWN IN THE UPPER RIDGE BY WEDNESDAY. THIS SCENARIO HAS VERY LITTLE SUPPORT FROM THE GFS WHICH MAINTAINS RIDGING THROUGH THE CONCLUSION OF THE FCST PERIOD. FOR NOW HAVE LEANED WITH MAINTAINING MAINLY A DRY FCST PENDING ADDITIONAL MODEL AGREEMENT AND CONTINUITY. IN GENERAL...EXPECT TEMPS TO RANGE ANYWHERE BETWEEN 10-15 DEGREES ABOVE NORMAL THROUGH THE PERIOD. && .AVIATION /13Z THURSDAY THROUGH MONDAY/... FOG DEVELOPED BETWEEN 8Z AND 10Z THIS MORNING, AND HAS BROUGHT THE ELM TERMINAL INTO LIFR TERRITORY. THE MODEL GUIDANCE HAS NOT BEEN AT ALL HELPFUL, AS THE RUC SOUNDINGS AND LAMP GUIDANCE ALL FAILED TO FORECAST THIS EVENT. SIMILAR CASES IN THE PAST GENERALLY SAW FOG LIFT BETWEEN 12Z AND 13Z, AND THAT IS WHAT WE ARE FORECASTING THIS MORNING. THE REMAINDER OF THE DAY WILL BE SUNNY WITH LIGHT WINDS, AND VFR CONDITIONS. ANOTHER ROUND OF FOG IS FORECAST TONIGHT, AS ATMOSPHERIC CONDITIONS WILL BE SIMILAR BUT WITH LESS MIXING WINDS TO CONTEND WITH. OUTLOOK... THURSDAY NIGHT TO MONDAY...VFR EXCEPT FOR POSSIBLE EARLY MORNING IFR/MVFR VALLEY FOG...MAINLY AT KELM. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && $$ SYNOPSIS...DJP NEAR TERM...CMG/DJP SHORT TERM...MDP LONG TERM...CMG/MDP AVIATION...DJP
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
641 AM EDT THU JUN 14 2012 .SYNOPSIS... HIGH PRESSURE IS IN CONTROL ACROSS THE EASTERN UNITED STATES. SEVERAL DAYS OF FAIR WEATHER WILL BE THE RESULT, WITH TEMPERATURES SLOWLY RISING THROUGH THE WEEKEND INTO NEXT WEEK. && .NEAR TERM /THROUGH TONIGHT/... PER THE CURRENT AVIATION DISCUSSION, WE ARE NOT FORECASTING MUCH FOG THIS MORNING. THERE IS TOO MUCH MIXING TO ALLOW THE ATMOSPHERE TO OVERCOME THE DRY/COLD AIR ADVECTION INSIDE THE BOUNDARY LAYER. SPOTTY LIGHT FOG WILL EXIST MAINLY EAST OF I-81 IN THE HIGHER MOISTURE. TEMPERATURES WILL BE BATTLING SOME LOW LEVEL COOL ADVECTION EARLY TODAY. WE ARE FORECASTING MAXES ON THE LOW SIDE OF GUIDANCE, AS MIX DOWN TEMPS ARE CONSIDERABLY COOLER THAN MOS. BETTER CHANCE FOR FOG FRIDAY MORNING AS MIXING WINDS WILL BE LIGHT, AND DRY ADVECTION WILL HAVE CEASED. FORECASTING PATCHY FOG MAINLY ALONG THE RIVER VALLEYS. && .SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... 330 AM UPDATE... SURFACE RIDGE OF HIGH PRESSURE WILL BE SPRAWLED OVER THE NORTHEAST AND MIDATLANTIC REGIONS DURING THE SHORT TERM PERIOD. HOWEVER...ALOFT...THE UPPER RIDGE AXIS WILL ONLY SLOWLY SHIFT FROM THE WESTERN TO CENTRAL GREAT LAKES. 1000-500MB THICKNESSES WILL ONLY EDGE UP SLIGHTLY. DRY ATMOSPHERE WITH A GOOD AMOUNT OF SUN WILL HELP DAYTIME HIGHS TO REACH SLIGHTLY ABOVE NORMAL. A LITTLE WRINKLE HAS SHOWN UP IN THE 00Z GFS RUN...IN THE FORM OF LIGHT QPF IN THE WESTERN ZONES SATURDAY AFTERNOON. GFS SOUNDINGS SHOW MARGINAL INSTABILITY AND PRECIPITABLE WATER AROUND AN INCH OR SO AT THAT TIME. MEANWHILE...NAM/ECMWF/GEM ARE RAIN FREE...YET THE NAM ALSO CLEARLY SHOWS THE REMAINS OF A WAVE DROPPING DOWN SOUTHWARD ON THE FRONT SIDE OF THE UPPER RIDGE...AS CAN BE SEEN VIA 500MB VORTICITY FIELD. MAJORITY OF MODELS AND ALL MOS NUMBERS SUGGEST KEEPING THINGS DRY. HIGH PRESSURE AT THE SURFACE AND ALOFT...WITH FAIRLY DRY ATMOSPHERE...SHOULD INHIBIT SHOWER DEVELOPMENT...OR AT LEAST CAUSE ENTRAINMENT ANY THAT TRY TO DEVELOP. GIVEN ALL OF THE ABOVE...A SINGLE GFS RUN COMPARED TO OTHER RUNS AND MODELS IS NOT ENOUGH FOR ME TO PLACE ANY MENTIONABLE POPS IN THE FORECAST FOR SATURDAY AT THIS TIME. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... 330 AM UPDATE... MODELS HAVE TRENDED TO A MORE GRADUAL PACE ON SETTING UP OF THE WARM RIDGE EARLY NEXT WEEK. STILL EXPECTING TEMPERATURES TO SWOON ABOVE NORMAL...IT WILL JUST TAKE LONGER FOR THE RIDGE AXIS TO FOLD OVER OUR REGION. FORECAST UPDATED ACCORDINGLY...BACKING OFF SLIGHTLY ON HOW QUICKLY THE WARMING IS EXPECTED TO OCCUR. EXPECTING WARMEST TEMPERATURES BY MIDWEEK...WITH MID 80S TO NEAR 90 CURRENTLY FIGURED FOR NEXT WEDNESDAY. PREVIOUS DISCUSSION... A VERY QUIET AND WARM PERIOD EXPECTED THROUGH THE EXTENDED TIME FRAME AS UPPER- LEVEL RIDGING CONTINUES TO DEVELOP ALONG THE EASTERN SEABOARD. AS THIS OCCURS...DISTURBANCES TRAVELING ACROSS THE NORTHERN PLAINS AND NORTHERN MISSISSIPPI VALLEY WILL BE DEFECTED NORTH OF THE REGION WHICH SHOULD KEEP OUR REGION DRY THROUGH AT LEAST TUESDAY. CORRESPONDING WITH THE INCREASE IN BUILDING HEIGHTS ALOFT...850 MB TEMPS ARE ALSO FORECAST TO INCREASE TO NEAR 20C BY TUE...WHICH WILL SUPPORT HIGH TEMPS REACHING INTO THE UPPER 80S TO POSSIBLY LOWER 90S BY EARLY NEXT WEEK. FCST UNCERTAINTY INCREASES TOWARDS THE CONCLUSION OF THE PERIOD AS THE NEWLY ARRIVING 12Z ECMWF SHOWS A GRADUAL BREAKDOWN IN THE UPPER RIDGE BY WEDNESDAY. THIS SCENARIO HAS VERY LITTLE SUPPORT FROM THE GFS WHICH MAINTAINS RIDGING THROUGH THE CONCLUSION OF THE FCST PERIOD. FOR NOW HAVE LEANED WITH MAINTAINING MAINLY A DRY FCST PENDING ADDITIONAL MODEL AGREEMENT AND CONTINUITY. IN GENERAL...EXPECT TEMPS TO RANGE ANYWHERE BETWEEN 10-15 DEGREES ABOVE NORMAL THROUGH THE PERIOD. && .AVIATION /12Z THURSDAY THROUGH MONDAY/... FOG DEVELOPED BETWEEN 8Z AND 10Z THIS MORNING, AND HAS BROUGHT THE ELM TERMINAL INTO LIFR TERRITORY. THE MODEL GUIDANCE HAS NOT BEEN AT ALL HELPFUL, AS THE RUC SOUNDINGS AND LAMP GUIDANCE ALL FAILED TO FORECAST THIS EVENT. SIMILAR CASES IN THE PAST GENERALLY SAW FOG LIFT BETWEEN 12Z AND 13Z, AND THAT IS WHAT WE ARE FORECASTING THIS MORNING. THE REMAINDER OF THE DAY WILL BE SUNNY WITH LIGHT WINDS, AND VFR CONDITIONS. ANOTHER ROUND OF FOG IS FORECAST TONIGHT, AS ATMOSPHERIC CONDITIONS WILL BE SIMILAR BUT WITH LESS MIXING WINDS TO CONTEND WITH. OUTLOOK... THURSDAY NIGHT TO MONDAY...VFR EXCEPT FOR POSSIBLE EARLY MORNING IFR/MVFR VALLEY FOG...MAINLY AT KELM. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...NONE. && $$ SYNOPSIS...DJP NEAR TERM...DJP SHORT TERM...MDP LONG TERM...CMG/MDP AVIATION...DJP
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1008 AM CDT THU JUN 14 2012 .DISCUSSION... MAIN CHANGE FOR THE MORNING UPDATE WAS TO ADJUST POPS FOR THE REST OF THE DAY. RADAR SHOWS THAT MOST OF THE CONVECTION HAS MOVED EAST OF THE CWA...WITH ONLY A FEW LINGERING SHOWERS. LOWERED POPS FOR THE MORNING HOURS. RUC AND TO A LESSER EXTENT HRRR SHOW SOME REDEVELOPMENT ALONG THE FRONTAL BOUNDARY AS IT MOVES INTO MN THIS AFTERNOON. THERE SHOULD BE SOME CAPE...SO CONTINUED TO KEEP LIKELY POPS WEST OF THE VALLEY FOR THIS AFTERNOON...ALTHOUGH ADJUSTED OUR SOUTHWESTERN COUNTIES DOWNWARD AS MOST OF THE REDEVELOPMENT WILL BE EAST OF THERE. THE NORTHWEST SHOULD SEE SOME WRAP AROUND PRECIP ON THE BACKSIDE OF THE SFC LOW THIS AFTERNOON...WHICH FITS ONGOING RADAR TRENDS ACROSS WESTERN ND WELL. LOWERED HIGHS A TINY BIT IN THE FAR EASTERN COUNTIES...BUT OTHERWISE KEPT HIGHS IN THE 70S TO LOW 80S AS WE SHOULD SEE A FAIR AMOUNT OF SUNSHINE AS THE DRY AIR INTRUSION MOVES IN. && .AVIATION... VFR CONDITIONS ARE EVERYWHERE BUT KBJI...AND THE IFR CEILINGS SHOULD CLEAR OUT OF THAT SITE IN THE NEXT FEW HOURS. SOME CONVECTIVE REDEVELOPMENT IS POSSIBLE AT KTVF AND KBJI THIS AFTERNOON...BUT THERE IS NOT ENOUGH CERTAINTY TO INCLUDE CEILING/VIS REDUCTIONS WITH THUNDERSTORMS AT THIS TIME. WEST WINDS WILL PICK UP THIS AFTERNOON INTO THE 20 TO 25 KT RANGE WITH SOME GUSTS ABOVE 30 KTS. && .PREV DISCUSSION... /ISSUED 221 AM CDT THU JUN 14 2012/ SHORT TERM... THE MAIN INITIAL CONCERN IS CURRENT SEVERE THUNDERSTORM WATCH...AND CONVECTIVE CHANCES WILL BE THE MAIN CHALLENGE THROUGH THE FORECAST. MODELS ARE IN OVERALL GOOD AGREEMENT...WITH TIMING DIFFERENCES FRI NIGHT WITH THE NAM THE FASTEST MODEL. THIS MAKES SENSE GIVEN VERY PROGRESSIVE FLOW...SO WILL TREND THINGS A BIT QUICKER WITH FRI NIGHT SYSTEM. FOR TODAY...EXPECT AN MCS TO BE ONGOING DURING THE MORNING HOURS LIKELY CROSSING INTO MN. THERE IS THE POTENTIAL FOR SOME SEVERE STORMS THIS MORNING...THEN AGAIN THIS AFTERNOON IN THE FAR EAST. THE MAIN COLD FRONT WILL BE INTO THE EASTERN AREAS THIS AFTERNOON...WITH HIGH SHEAR AND DECENT CAPE...SEVERE STORMS WILL BE POSSIBLE. WINDS WILL ALSO INCREASE THIS AFTERNOON AND COULD GET TO NEAR ADVISORY LEVELS MAINLY IN THE DVL BASIN...BUT NO HEADLINES ATTM. FOR TONIGHT...EXPECT CONVECTION TO MOVE OUT OF THE EAST SHORTLY AFTER 03Z. PWATS WILL DECREASE AND EXPECT CLEARING FROM WEST TO EAST WITH A WEAK SFC RIDGE BUILDING IN BY 12Z FRI. ON FRI...THE DAYLIGHT HOURS SHOULD REMAIN DRY WITH THE NEXT SHORTWAVE APPROACHING WESTERN ND LATE IN THE DAY. TEMPS SHOULD WARM ABOVE NORMAL WITH PLENTY OF INSOLATION AND JUST SOME INCREASING HIGH CLOUDS DURING THE AFTERNOON. FOR FRI NIGHT...ANOTHER SHORTWAVE WILL MOVE THROUGH THE REGION WITH AN INCREASING LLJ. THIS SYSTEM WILL BE VERY SIMILAR TO TONIGHTS CONVECTION...SO THERE IS THE POTENTIAL ONCE AGAIN FOR SOME SEVERE STORMS. ON SAT...ANOTHER COLD FRONT WILL PASS THROUGH THE REGION WITH THE THREAT FOR THUNDER CONTINUING...WITH SOME STORMS POSSIBLY SEVERE MAINLY IN THE EAST. LONG TERM...SUNDAY THROUGH WEDNESDAY GFS/ECMWF/GEM/DGEX NOT IN THE BEST AGREEMENT EARLY NEXT WEEK...BUT GENERAL IDEA IS FOR CONTINUED WEST-SOUTHWEST FLOW ALOFT WITH A SERIES OF EMBEDDED SHORT-WAVES. TIMING AND LOCATION UNCERTAINTIES ABOUND AND WILL MAINTAIN ALLBLEND CHANCE POPS THROUGHOUT THE PERIOD. HIGH TEMPERATURES IN THE 70S/LOWER 80S AND LOWS IN THE 50S WILL BE THE GENERAL RULE. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ JR
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
1022 AM CDT THU JUN 14 2012 .AVIATION... NO SIGNIFICANT CHANGE WAS MADE TO THE 12Z TAFS. ALTHOUGH NOT INDICATED IN THE 15Z UPDATED TAFS...ISOLATED THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON...THIS WILL BE ADDRESSED FURTHER IN THE 18Z TAFS. 58 .../PREVIOUS AVIATION DISCUSSION/... CONVECTION SHOULD REMAIN EAST OF TAF SITES TODAY AS LINGERING BOUNDARY HEADS OFF TO THE NORTHEAST. THUS CHANCE OF CONVECTION OCCURRING AT TAF SITES IS TOO LOW TO MENTION. VFR IS EXPECTED AT METROPLEX TAF SITES THROUGH THIS EVENING. MVFR STRATUS AT 015 IS LOCATED TO THE SOUTH THIS MORNING AND SHOULD STAY SOUTHEAST OF TAF SITES...BUT MAY BRIEFLY IMPACT GKY/DAL. SOUTH WINDS 10-15KT WILL PREVAIL. A ROUND OF MVFR STRATUS IS EXPECTED LATE TONIGHT AROUND 10Z. FOR WACO...STRATUS SHOULD CONTINUE THROUGH 15Z OR SO BEFORE LIFTING. VFR WITH SOUTH WINDS AT 10-15KT WILL PREVAIL THROUGH THIS EVENING...BUT EXPECT STRATUS AGAIN LATE TONIGHT AROUND 10Z. 58 && .UPDATE... SCATTERED CONVECTION CONTINUES MAINLY ACROSS THE NORTHEAST...BUT RECENT RADAR RETURNS HAVE BEEN NOTED IN MONTAGUE COUNTY. THE REMNANT OUTFLOW BOUNDARY REMAINS DRAPED ACROSS THE AREA AND LATEST SURFACE ANALYSIS HAS THIS BOUNDARY ALONG A LINE NEAR BOWIE TO MCKINNEY TO CANTON. THIS BOUNDARY CAN BE IDENTIFIED BY THE SHIFT OF A SOUTHERLY WIND TO A SOUTHEAST WIND. THE 12Z FWD SOUNDING HAD 30 KNOTS OF LOW LEVEL FLOW UP TO 800 MB. THIS FLOW IS LIKELY BEING ASCENDED UP AND OVER THE BOUNDARY ENHANCING THE LOW LEVEL LIFT. THIS CAN BE SEEN ON THE THE 305K ISENTROPIC CHART. OVER THE NEXT COUPLE OF HOURS...EXPECT THIS BOUNDARY TO SHIFT NORTH AND THE LOW LEVEL JET TO WEAKEN. THIS SHOULD ALLOW FOR OUR LIFT TO DIMINISH AND A BREAK FROM THE STORMS LATE THIS MORNING AND EARLY AFTERNOON. THE HRRR IS DEVELOPING WIDESPREAD THUNDERSTORMS ALONG A SOUTHWARD MOVING BOUNDARY TODAY WITH THUNDERSTORMS INTO THE METROPLEX AROUND NOON. THE 14Z FORECAST FROM THE HRRR ALREADY SEEMS OUT OF THE LOOP AND WILL NOT GIVE MUCH WEIGHT TO ITS FORECAST. FOR THE AFTERNOON...PEAK HEATING SHOULD ALLOW FOR SOME THUNDERSTORM DEVELOPMENT ACROSS NORTH TEXAS. LOCATIONS IN THE EASTERN ZONES WILL HAVE THE BEST CHANCES WHERE THERE IS HIGHER MOISTURE. YESTERDAYS SEVERE WEATHER EPISODE WAS IN PART DUE TO MID-LEVEL WINDS OF 35-40 KNOTS ON THE BACKSIDE OF AN UPPER LOW. THESE WINDS HAVE SINCE SHIFTED EAST AND 500 MB WINDS ARE ONLY EXPECTED TO BE 10-25 KNOTS WITH THE HIGHEST WINDS IN THE SOUTHEAST. GIVEN THE HIGHER MOISTURE...25 KNOT MID-LEVEL FLOW AND ADEQUATE INSTABILITY...SOME SEVERE STORMS ARE POSSIBLE...MAINLY IN THE SOUTHEASTERN ZONES THIS AFTERNOON. HOWEVER...DO NOT ANTICIPATE LONG-LIVED SUPERCELLS LIKE YESTERDAY...AS SHEAR ISNT EXPECTED TO BE AS STRONG. 85/NH && .PREV DISCUSSION... /ISSUED 305 AM CDT THU JUN 14 2012/ ATMOSPHERE REFUSES TO STABILIZE...AS MODELS HAVE TRIED TO FORECAST FOR A COUPLE OF DAYS NOW. GUIDANCE NOW HOLDS SOME INSTABILITY AND LOW PRECIP CHANCES IN THEIR OUTPUT THROUGH THURSDAY NIGHT AND THAT IS WHAT I AM FORECASTING. FOR THIS MORNING...A WEAK BOUNDARY OR FRONT REMAINS DRAPED ACROSS NORTH TEXAS...RUNNING GENERALLY FROM PALESTINE TO EASTLAND. A FEW STORMS HAVE FIRED IN NORTHWEST COUNTIES...BUT SEEM TO BE WEAKENING. AN AREA OF CONVECTION IN THE EAST...CENTERED BETWEEN ATHENS AND FAIRFIELD...HAS BECOME LARGER IN THE LAST FEW HOURS. NO ORGANIZED SEVERE WEATHER IS EXPECTED...BUT SEVERE WARNINGS WERE ISSUED EARLIER TONIGHT FOR STORMS FARTHER SOUTHEAST NEAR CROCKETT. I HAVE ADDED SLIGHT CHANCE POPS FOR TODAY NORTHEAST OF A LINE FROM GRAHAM TO LEONA...AND CONTINUED POPS IN THE NORTHEASTERN HALF OF NORTH TEXAS THROUGH MIDNIGHT. RIDGING IS STILL PROGGED TO MOVE ACROSS THE AREA FRIDAY THROUGH MONDAY...BUT BY TUESDAY AN INVERTED TROF...EXTENDING NORTH FROM A TROPICAL DISTURBANCE IN THE GULF...WILL WEAKEN THE RIDGE AND MAY PROVIDE SOME CONVECTIVE POTENTIAL. I HAVE ADDED LOW POPS WEDNESDAY IN THE EAST AS A RESULT. WITH SOUTH FLOW EXPECTED ALL WEEK...I AM STILL FORECASTING SEASONABLY WARM TEMPERATURES...LOWS IN THE 70S AND HIGHS IN THE UPPER 80S/LOW 90S. SINCE THE RIDGE IS NOT PROGGED TO BE AS STRONG AS THE USUAL MID-SUMMER //DEATH RIDGE//...THIS SHOULD LIMIT THE INVERSION STRENGTH AND THUS THE POTENTIAL FOR VERY HIGH AFTERNOON TEMPERATURES. 84 && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 93 73 92 75 93 / 20 20 5 5 5 WACO, TX 93 74 94 73 93 / 10 10 5 5 5 PARIS, TX 90 69 90 69 89 / 30 20 10 5 5 DENTON, TX 92 71 91 73 92 / 20 20 5 5 5 MCKINNEY, TX 91 71 90 72 91 / 20 20 10 5 5 DALLAS, TX 93 74 92 75 93 / 20 20 5 5 5 TERRELL, TX 92 72 92 73 92 / 20 20 10 5 5 CORSICANA, TX 92 72 94 73 92 / 20 20 5 5 5 TEMPLE, TX 92 75 92 73 92 / 10 10 5 5 5 MINERAL WELLS, TX 94 70 91 70 91 / 20 10 5 5 5 && .FWD WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 58/85
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
917 AM CDT THU JUN 14 2012 .UPDATE... SCATTERED CONVECTION CONTINUES MAINLY ACROSS THE NORTHEAST...BUT RECENT RADAR RETURNS HAVE BEEN NOTED IN MONTAGUE COUNTY. THE REMNANT OUTFLOW BOUNDARY REMAINS DRAPED ACROSS THE AREA AND LATEST SURFACE ANALYSIS HAS THIS BOUNDARY ALONG A LINE NEAR BOWIE TO MCKINNEY TO CANTON. THIS BOUNDARY CAN BE IDENTIFIED BY THE SHIFT OF A SOUTHERLY WIND TO A SOUTHEAST WIND. THE 12Z FWD SOUNDING HAD 30 KNOTS OF LOW LEVEL FLOW UP TO 800 MB. THIS FLOW IS LIKELY BEING ASCENDED UP AND OVER THE BOUNDARY ENHANCING THE LOW LEVEL LIFT. THIS CAN BE SEEN ON THE THE 305K ISENTROPIC CHART. OVER THE NEXT COUPLE OF HOURS...EXPECT THIS BOUNDARY TO SHIFT NORTH AND THE LOW LEVEL JET TO WEAKEN. THIS SHOULD ALLOW FOR OUR LIFT TO DIMINISH AND A BREAK FROM THE STORMS LATE THIS MORNING AND EARLY AFTERNOON. THE HRRR IS DEVELOPING WIDESPREAD THUNDERSTORMS ALONG A SOUTHWARD MOVING BOUNDARY TODAY WITH THUNDERSTORMS INTO THE METROPLEX AROUND NOON. THE 14Z FORECAST FROM THE HRRR ALREADY SEEMS OUT OF THE LOOP AND WILL NOT GIVE MUCH WEIGHT TO ITS FORECAST. FOR THE AFTERNOON...PEAK HEATING SHOULD ALLOW FOR SOME THUNDERSTORM DEVELOPMENT ACROSS NORTH TEXAS. LOCATIONS IN THE EASTERN ZONES WILL HAVE THE BEST CHANCES WHERE THERE IS HIGHER MOISTURE. YESTERDAYS SEVERE WEATHER EPISODE WAS IN PART DUE TO MID-LEVEL WINDS OF 35-40 KNOTS ON THE BACKSIDE OF AN UPPER LOW. THESE WINDS HAVE SINCE SHIFTED EAST AND 500 MB WINDS ARE ONLY EXPECTED TO BE 10-25 KNOTS WITH THE HIGHEST WINDS IN THE SOUTHEAST. GIVEN THE HIGHER MOISTURE...25 KNOT MID-LEVEL FLOW AND ADEQUATE INSTABILITY...SOME SEVERE STORMS ARE POSSIBLE...MAINLY IN THE SOUTHEASTERN ZONES THIS AFTERNOON. HOWEVER...DO NOT ANTICIPATE LONG-LIVED SUPERCELLS LIKE YESTERDAY...AS SHEAR ISNT EXPECTED TO BE AS STRONG. 85/NH && .AVIATION... CONVECTION SHOULD REMAIN EAST OF TAF SITES TODAY AS LINGERING BOUNDARY HEADS OFF TO THE NORTHEAST. THUS CHANCE OF CONVECTION OCCURRING AT TAF SITES IS TOO LOW TO MENTION. VFR IS EXPECTED AT METROPLEX TAF SITES THROUGH THIS EVENING. MVFR STRATUS AT 015 IS LOCATED TO THE SOUTH THIS MORNING AND SHOULD STAY SOUTHEAST OF TAF SITES...BUT MAY BRIEFLY IMPACT GKY/DAL. SOUTH WINDS 10-15KT WILL PREVAIL. A ROUND OF MVFR STRATUS IS EXPECTED LATE TONIGHT AROUND 10Z. FOR WACO...STRATUS SHOULD CONTINUE THROUGH 15Z OR SO BEFORE LIFTING. VFR WITH SOUTH WINDS AT 10-15KT WILL PREVAIL THROUGH THIS EVENING...BUT EXPECT STRATUS AGAIN LATE TONIGHT AROUND 10Z. && .PREV DISCUSSION... /ISSUED 305 AM CDT THU JUN 14 2012/ ATMOSPHERE REFUSES TO STABILIZE...AS MODELS HAVE TRIED TO FORECAST FOR A COUPLE OF DAYS NOW. GUIDANCE NOW HOLDS SOME INSTABILITY AND LOW PRECIP CHANCES IN THEIR OUTPUT THROUGH THURSDAY NIGHT AND THAT IS WHAT I AM FORECASTING. FOR THIS MORNING...A WEAK BOUNDARY OR FRONT REMAINS DRAPED ACROSS NORTH TEXAS...RUNNING GENERALLY FROM PALESTINE TO EASTLAND. A FEW STORMS HAVE FIRED IN NORTHWEST COUNTIES...BUT SEEM TO BE WEAKENING. AN AREA OF CONVECTION IN THE EAST...CENTERED BETWEEN ATHENS AND FAIRFIELD...HAS BECOME LARGER IN THE LAST FEW HOURS. NO ORGANIZED SEVERE WEATHER IS EXPECTED...BUT SEVERE WARNINGS WERE ISSUED EARLIER TONIGHT FOR STORMS FARTHER SOUTHEAST NEAR CROCKETT. I HAVE ADDED SLIGHT CHANCE POPS FOR TODAY NORTHEAST OF A LINE FROM GRAHAM TO LEONA...AND CONTINUED POPS IN THE NORTHEASTERN HALF OF NORTH TEXAS THROUGH MIDNIGHT. RIDGING IS STILL PROGGED TO MOVE ACROSS THE AREA FRIDAY THROUGH MONDAY...BUT BY TUESDAY AN INVERTED TROF...EXTENDING NORTH FROM A TROPICAL DISTURBANCE IN THE GULF...WILL WEAKEN THE RIDGE AND MAY PROVIDE SOME CONVECTIVE POTENTIAL. I HAVE ADDED LOW POPS WEDNESDAY IN THE EAST AS A RESULT. WITH SOUTH FLOW EXPECTED ALL WEEK...I AM STILL FORECASTING SEASONABLY WARM TEMPERATURES...LOWS IN THE 70S AND HIGHS IN THE UPPER 80S/LOW 90S. SINCE THE RIDGE IS NOT PROGGED TO BE AS STRONG AS THE USUAL MID-SUMMER //DEATH RIDGE//...THIS SHOULD LIMIT THE INVERSION STRENGTH AND THUS THE POTENTIAL FOR VERY HIGH AFTERNOON TEMPERATURES. 84 && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 93 73 92 75 93 / 20 20 5 5 5 WACO, TX 93 74 94 73 93 / 10 10 5 5 5 PARIS, TX 90 69 90 69 89 / 30 20 10 5 5 DENTON, TX 92 71 91 73 92 / 20 20 5 5 5 MCKINNEY, TX 91 71 90 72 91 / 20 20 10 5 5 DALLAS, TX 93 74 92 75 93 / 20 20 5 5 5 TERRELL, TX 92 72 92 73 92 / 20 20 10 5 5 CORSICANA, TX 92 72 94 73 92 / 20 20 5 5 5 TEMPLE, TX 92 75 92 73 92 / 10 10 5 5 5 MINERAL WELLS, TX 94 70 91 70 91 / 20 10 5 5 5 && .FWD WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 85/85
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
330 PM EDT THU JUN 14 2012 .SYNOPSIS... ISSUED AT 330 PM EDT THU JUN 14 2012 AN UPPER LEVEL RIDGE OVER THE LOWER GREAT LAKES REGION WILL CONTINUE TO PRODUCE PREDOMINANTLY DRY WEATHER THROUGH SATURDAY AFTERNOON. A FEW LIGHT SHOWERS MAY CLIP NORTH CENTRAL LOWER MICHIGAN TONIGHT BEFORE DISSIPATING. TEMPERATURES WILL UNDERGO A MODERATING TREND FRIDAY AND SATURDAY WITH WINDS STAYING OUT OF THE SOUTH. A WEAKENING FRONTAL BOUNDARY WILL BRING THE NEXT CHANCE OF SHOWERS AND THUNDERSTORMS SATURDAY NIGHT AND SUNDAY. TEMPERATURES WILL CONTINUE TO AVERAGE AT LEAST TEN TO FIFTEEN DEGREES ABOVE NORMAL FOR MOST OF NEXT WEEK. && .SHORT TERM...(TONIGHT THROUGH SATURDAY NIGHT) ISSUED AT 330 PM EDT THU JUN 14 2012 PRIMARY SHORT TERM FCST CHALLENGES INVOLVE DETERMINING HOW WARM IT WILL BECOME FRIDAY AND SATURDAY AND TO EVALUATE POTENTIAL FOR SHOWERS AND TSTORMS LATE SATURDAY NIGHT. WE ALSO NEED TO DETERMINE POTENTIAL FOR ANY SHOWERS FROM A DISSIPATING MCS OVER NORTHERN WI ATTM TO CLIP OUR AREA OVERNIGHT. A CONSENSUS OF 12Z SHORT RANGE GUIDANCE SUGGESTS MCS ACTIVITY OVER NORTHERN WI/SOUTHERN MN WILL STAY TO OUR NW TONIGHT. THAT IS WHERE STRONG FORCING FROM THE LLJ WILL CONTINUE TO FOCUS CONVECTIVE DEVELOPMENT/REDEVELOPMENT. IT IS NOT IMPOSSIBLE THAT SOME DYING SHOWERS OVERNIGHT MAY FLIRT WITH OUR NORTHERNMOST COUNTIES (MAINLY NORTH OF A LINE FROM LDM TO MOP) AS SUGGESTED BY THE HRRR AND EXTRAPOLATION OF CURRENT RGNL RADAR TRENDS. I HAVE ADDED MENTION OF JUST A SLIGHT CHC OF SHOWERS ACROSS OUR NORTHERNMOST TIER OF COUNTIES LATE TONIGHT TO ACCOUNT FOR THIS. LAPS SOUNDINGS FROM ACROSS OUR FCST AREA LOOK VERY DRY THOUGH AND I WOULD EXPECT THE EASTERN WING OF THE DECAYING MCS TO CONTINUE TO WEAKEN OVER EASTERN WI WHILE NEW CONVECTION TAKES OFF OVER WESTERN WI WHERE THE ROBUST LLJ FORCING IS. WE WILL MAINLY JUST SEE MID TO HIGH LEVEL CLOUD BLOWOFF FROM THAT ACTIVITY CONTINUE TO ADVECT IN FROM THE NW LATE THIS AFTN/TONIGHT. FAIR/MILDER WX ANTICIPATED FRIDAY WITH THE UPPER RIDGE IN PLACE. MAX TEMPS TOMORROW WILL REACH THE MID TO UPPER 80S IN CONTINUED SOUTHERLY FLOW WAA AND WITH H8 TEMPS REACHING 17-18 C BY TOMORROW AFTN. HOT CONDITIONS ANTICIPATED FOR SATURDAY WITH SOUTHERLY FLOW WAA CONTINUING AND H8 TEMPS MODERATING TO 19 TO 20 C. THIS SHOULD RESULT IN MAX TEMPS REACHING THE UPPER 80S TO LOWER 90S. INCREASING MID TO HIGH CLOUDS FROM THE WEST SATURDAY AFTERNOON WILL NOT INHIBIT IT FROM BECOMING HOT BY SATURDAY AFTERNOON. WILL CARRY LOW CHC POPS FOR SCATTERED SHOWERS/TSTORMS VERY LATE SATURDAY NIGHT. THIS BASED LARGELY ON 12Z GFS GUIDANCE SHOWING THE APPROACH OF THE WEAKENING FRONT AND INCREASING 1000-850 MB MOISTURE TRANSPORT DEVELOPING OVERNIGHT. HOWEVER IT IS NOTED THAT 12Z NAM GUIDANCE KEEPS IT DRY THRU 12Z SUNDAY AND THE 00Z/12Z ECMWF ONLY BRINGS A FEW SHOWERS INTO OUR NW FCST AREA TOWARD DAYBREAK SUNDAY. SO OVERALL IT STILL LOOKS LIKE A (SLIGHTLY) BETTER CHC FOR A FEW SHOWERS/STORMS WILL HOLD OFF UNTIL SUNDAY. .LONG TERM...(SUNDAY THROUGH THURSDAY) ISSUED AT 330 PM EDT THU JUN 14 2012 THE MAIN CHALLENGE IN THE LONG TERM IS THE CHANCE FOR THUNDERSTORMS. THE MID RANGE MODELS ARE SHOWING PERSISTENT HIGH PRESSURE OVER THE SOUTHEAST OF THE UNITED STATES WITH STORM SYSTEMS FROM THE WEST BEING PUSHED UP TO THE NORTHWEST OF LOWER MICHIGAN. FEEL THAT LAKE MICHIGAN MAY ACT AS AN ADDITIONAL BARRIER TO THE WEST OF LOWER MICHIGAN. A COUPLE SYSTEMS MIGHT BE ABLE TO SOMEWHAT FLATTEN THE RIDGE AND BRING THUNDERSTORMS TO THE AREA. THE FIRST WOULD DRAG A COLD FRONT THROUGH SUNDAY INTO MONDAY. NOT IMPRESSED WITH THE MOISTURE AVAILABLE WITH THIS FRONT AND THE DYNAMICS REMAIN TO THE NORTHWEST AND NORTH. ANOTHER STRONG PUSH IS POSSIBLE LATE TUESDAY INTO WEDNESDAY. THINK WITH THE BLOCKING HIGH IN PLACE... THIS MAY NOT PASS UNTIL POSSIBLY WEDNESDAY NIGHT OR THURSDAY. MOST OF THE ENERGY WITH THIS SYSTEM ALSO PASSES TO THE NORTH. OVERALL... IT LOOKS WARM WITH ONLY A CHANCE OF THUNDERSTORMS SUNDAY/ SUNDAY NIGHT AND WEDNESDAY/THURSDAY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 1223 PM EDT THU JUN 14 2012 VFR CONDITIONS TO PREVAIL AT TAF SITES THROUGH TOMORROW AFTERNOON. WITH HIGH PRESSURE TO THE NORTHEAST... A LIGHT SOUTHEAST FLOW WILL SLOWLY TURN TO THE SOUTH. HIGH AND MID CLOUDS WILL MOVE OVER THE AREA... BUT PRECIPITATION IS NOT EXPECTED. && .MARINE... ISSUED AT 330 PM EDT THU JUN 14 2012 SOUTHERLY WINDS ANTICIPATED THROUGH SATURDAY GENERALLY IN THE 5 TO 15 KT RANGE. THIS WILL RESULT IN WAVE HEIGHTS OF ONLY AROUND 2 FEET OR LESS. FOG MAY BECOME AN ISSUE THIS WEEKEND AS AN INCREASINGLY WARM/HUMID AIRMASS OVERRUNS RELATIVELY COOLER LAKE WATERS. && .HYDROLOGY... ISSUED AT 330 PM EDT THU JUN 14 2012 NO HYDRO ISSUES ANTICIPATED IN THE SHORT TERM WITH DRY WX TO CONTINUE THROUGH SATURDAY AFTERNOON. A WEAKENING FRONT WILL BRING A CHC OF SHOWERS AND TSTORMS SATURDAY NIGHT AND SUNDAY. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...NONE. && $$ SYNOPSIS...LAURENS SHORT TERM...LAURENS LONG TERM...63 AVIATION...63 HYDROLOGY...LAURENS MARINE...LAURENS
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
303 PM CDT THU JUN 14 2012 .DISCUSSION... THE MAIN CHALLENGE OVER THE NEXT SEVERAL DAYS ARE THUNDERSTORM CHANCES AND THE THREAT OF SEVERE WEATHER THROUGH EARLY PART OF NEXT WEEK. THE LATEST MODEL RUN...CONTINUE TO INDICATE A VERY ACTIVE WEATHER PATTERN OVER THE UPPER MIDWEST OVER THE NEXT FIVE DAYS WITH SEVERAL SHORTWAVE TROUGH MOVING THROUGH THE NORTHERN TIER OF THE CONUS. THIS AFTERNOON...A DEEP UPPER LOW PRESSURE SYSTEM WAS LOCATED JUST WEST OF LAKE WINNIPEG CANADA. THIS SYSTEM IS FORECAST TO LIFT NORTHEAST...AND DRAG A COLD FRONT THROUGH MUCH OF THE UPPER MIDWEST BY FRIDAY MORNING. THE FRONT WILL EVENTUALLY STALL OVER SOUTHEAST MN AND CENTRAL WISCONSIN LATER TONIGHT. ON GOING CONVECTION ASSOCIATED WITH MESOSCALE CONVECTIVE SYSTEM WILL CONTINUE TO ADVANCE EAST THROUGH THE WESTERN GREAT LAKES THIS EVENING. THE LATEST IR SATELLITE IMAGERY SHOWED THE SYSTEM WAS BACKBUILDING OVER SOUTHERN MINNESOTA. THIS AFTERNOON...A WARM FRONT STRETCH OVER THE SOUTHERN THIRD OF MN INTO A LOW PRESSURE SYSTEM OVER WEST CENTRAL MN. THE COMBINATION OF OLD OUTFLOW BOUNDARY...WARM FRONTAL BOUNDARY AND APPROACHING COLD FRONT WILL HELP INSTIGATE ADDITIONAL THUNDERSTORMS. MORNING ROUND OF THUNDERSTORMS HAD COOLED DOWN THE ATMOSPHERE...WHERE THE FREEZING LEVEL HAS LOWER FROM 13700 FEET EARLIER. MUCH OF THE SEVERE WEATHER TODAY WAS LARGE HAIL...WITH HAIL UP TO AN INCH. ANOTHER ROUND OF STRONG TO SEVERE STORMS ARE POSSIBLE FRIDAY AFTERNOON/EVENING OVER SOUTH CENTRAL MN AND WEST CENTRAL WISCONSIN WITH A MORE WIDESPREAD RISK OF SEVERE STORMS SATURDAY. THE LATEST GEM-NHEM INDICATED MORE OF THE SAME NEXT WEEK WITH SEVERAL MORE BOUTS OF SEVERE WEATHER POSSIBLE WEDNESDAY AND THURSDAY. && .AVIATION.../18Z TAF ISSUANCE/ A WARM FRONT EXTENDS ALONG THE MINNESOTA RIVER VALLEY AND HAS PRODUCED SEVERAL BOUTS OF CONVECTION IN EAST CENTRAL MN AND EXTREME WESTERN WISCONSIN THIS MORNING AND EARLY AFTERNOON. THESE STORMS HAVE BEEN MORE OF A HAIL THREAT THAN A WIND THREAT WITH NICKLE SIZE HAIL AND GUSTS IN THE 30KT RANGE. A COLD FRONT IS MOVING INTO WESTERN MN AT THIS TIME WITH CLEARING JUST AHEAD AND BEHIND THE FRONT. THE WARM FRONT WILL MOVE TOWARD MSP AROUND 22Z AND THE COLD FRONT/TROUGH MOVES INTO CENTRAL MN AT THAT TIME. THERE IS FAIR AMOUNT OF UNCERTAINTY AS TO HOW MUCH CONVECTION WILL DEVELOP AHEAD OF THE COLD FRONT DUE TO THE ONGOING CONVECTION FOR STC/MSP/RNH. DO NOT EXPECT TO SEE ANY SIGNIFICANT AMOUNT OF HEATING DUE TO CLOUD COVER AT THESE SITES THEREFORE TS ACTIVITY MAY NOT BE AS INTENSE. HRRR TRIES TO DEVELOP CONVECTION 19/20Z TIME FRAME AHEAD OF THE FRONT IN THE AXN AREA BUT STRUGGLES UNTIL WE GET TO THE 22/23Z TIME FRAME. BY THIS TIME CONVECTION IS LIMITED TO RNH/MSP AND SOUTHEAST OF RWF. HRRR HAS IT OUT OF THE MSP/RNH SITES BY 02Z AND OUT OF EAU BY 04Z. KMSP...TS ACTIVITY IS MAINLY SOUTHWEST OF THE FIELD AND EAST TO NORTHEAST OF THE FIELD. DO NOT EXPECT MUCH ADDITIONAL ACTIVITY UNTIL 22/23Z...AS THE FRONT APPROACHES. CONFIDENCE IS NOT REAL GOOD AT THIS TIME THOUGH. NOT SURE THE WARM FRONT WILL MAKE IT NORTH OF THE AIRFIELD BEFORE THE COLD FRONT/TROUGH ARRIVES AROUND 00Z. IF NOT WINDS IN THE TAF ARE TOO STRONG. /OUTLOOK/ FRIDAY...VFR. SATURDAY...MVFR/VFR WITH TSRA POSSIBLE. BEST CHANCES AFTN/EVN. SUNDAY...MVFR/VFR WITH TSRA POSSIBLE BUT LOW CONFIDENCE. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ JM/DL
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
118 PM CDT THU JUN 14 2012 ...UPDATED FOR 18Z AVIATION DISCUSSION BELOW. .DISCUSSION... OVERVIEW...SEVERAL BOUTS OF RAIN LIKELY OVER THE COMING DAYS WITH ABOVE NORMAL TEMPERATURES. MORE HUMIDITY ARRIVES TODAY AND LINGERS INTO EARLY NEXT WEEK. THE GRAND FORKS AND ABERDEEN NWS OFFICES HAVE BEEN DOING BATTLE WITH ELEVATED THUNDERSTORMS AND POTENTIALLY LARGE HAIL THIS MORNING. THESE STORMS ARE NOW ON THE FRINGE OF THE WESTERN BORDER OF OUR FORECAST AREA. THE LEADING AREA OF STORMS ARE ON THE NOSE OF A VERY STRONG 850MB JET AND IN THE AREA OF WARM AIR ADVECTION. SO FAR...THERE HAS NOT BEEN MUCH SOUTHWARD DEVELOPMENT. IN FACT...THERE IS DEVELOPMENT BACK TO THE NORTHWEST WITH TIGHTENING 850MB-700MB ISOTHERMS. THE 700MB FRONTOGENESIS IS LIKELY THE RESULT OF THE APPROACHING TROUGH ENTERING THE NORTHERN PLAINS. THE MOISTURE IS ALSO MUCH BETTER BACK TOWARD CENTRAL ND/SD. NONETHELESS...INCLUDED HIGH POPS IN CENTRAL MN TO ACCOUNT FOR THE EASTWARD MOVEMENT WITH TIME ALTHOUGH WOULDNT BE SURPRISED TO SEE A WEAKENING TREND. INCLUDED AT LEAST CHANCE POPS MUCH FURTHER SOUTH TO ACCOUNT FOR DEVELOPMENT WHERE THE GOOD MOISTURE TRANSPORT IS POINTING AND PWATS ARE ON THE RISE. ACTUALLY ITS 09Z AND JUST NOW SEEING SOME LIGHT ELEVATED ECHOES OVER THE METRO. REGARDLESS OF WHAT HAPPENS THIS MORNING...WIDESPREAD SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP ACROSS WESTERN MN THIS AFTERNOON OUT AHEAD OF THE COLD FRONT. WARM FRONT SHOULD MAKE RAPID PROGRESS TO THE NORTH TODAY AND WILL LIKELY EXTENDED FROM NORTH CENTRAL MN INTO WEST CENTRAL BY 21Z THIS AFTERNOON. THE NEW SPC DAY1 HAS A 10% TORNADO PROBABILITY IN EAST CENTRAL MN AND WEST CENTRAL WI. CAN`T REALLY ARGUE WITH THIS GIVEN THE 0-1KM SRH AND BULK SHEAR OFF THE NAM AND RAP...RIGHT AROUND 100-200 M2/S2 AND 20KTS RESPECTIVELY AROUND 21Z THIS AFTERNOON IN EASTERN MN. THE MOST FAVORABLE LOW LEVEL WIND FIELD LIFTS NORTH LATE THIS MORNING TOWARDS DULUTH. FURTHERMORE...THE TOP 15 DATES FROM THE CIPS WARM SEASON ANALOG OFF THE 00Z NAM FROM LAST NIGHT DOES CONCENTRATE THE TORNADO REPORTS IN EAST CENTRAL MN...WITH THE WIND AND HAIL COVERING A MUCH LARGER AREA. MAX UPDRAFT HELICITY FROM OUR LOCAL WRF-ARW...AND TO SOME DEGREE NCEP WRF ARW/NMM...HAVE A COUPLE CLUSTERS OF +50 M2S2 BY 15.00Z ALONG A LINE FROM DULUTH TO ALBERT LEA WITH SLIGHTLY BACKED WINDS NEAR THE WARM FRONT NORTH OF THE TWIN CITIES METRO. IN TERMS OF TIMING...21Z IN CENTRAL MN...00-01Z IN EASTERN MN...AND 04Z CLEARING WEST CENTRAL WI IS A GOOD FIRST GUESS BASED ON SHORT-TERM MODEL CONSENSUS. MODEL GUIDANCE HAS BEEN CONSISTENT IN DEPICTING A SHORT WAVE TROUGH OVER THE NORTHERN PLAINS AT 12Z SATURDAY...ITS EVOLUTION IS STILL SOMEWHAT UNCERTAIN IN BOTH TIMING AND HOW MUCH IT DEEPENS. THE RESULTANT SFC CYCLONE AND COLD FRONT ARE THEREFORE AFFECTED...SO DIFFICULT TO GET A HANDLE ON THE INTENSITY AND TIMING OF CONVECTION ON SATURDAY...ALTHOUGH THINK THERE WILL BE GOOD STORM COVERAGE. OVERNIGHT CONVECTION AND OUTFLOW BOUNDARIES FURTHER COMPLICATE THE INSTABILITY PARAMETERS AND SEVERE POTENTIAL ON SATURDAY. STILL TRACKING THAT VORT MAX THAT ARRIVES FRIDAY NIGHT/SATURDAY AS MAIN TROUGH LIFTS NORTH INTO ONTARIO. SHORTWAVE ORIGINATING OUT OF CO TONIGHT AND TRACKING NE ACROSS THE CENTRAL PLAINS AND ENDING UP IN SOUTHERN MN BY SATURDAY MORNING. IT ORIGINATES OUT OF CONVECTION IN THE SOUTHWEST WITH GOOD DIFFLUENCE OUT AHEAD OF THE LONG WAVE TROUGH IN THE SOUTHWEST - SO LIKELY CONVECTIVE INDUCED. IN THE EXTENDED...LONG WAVE TROUGHING BECOMING ESTABLISHED DEEPENING AS IT PROGRESSES ACROSS THE NORTHERN PLAINS WITH TIME. STRONG TO SEVERE THUNDERSTORMS ARE POSSIBLE BETWEEN THE NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY EARLY NEXT WEEK AS DYNAMICS ASSOCIATED WITH A DEEP CYCLONE MOVING NORTH OF THE US/CANADIAN BORDER AT THAT TIME INTERACT WITH MOISTURE EXPECTED ACROSS THE REGION. AS MENTIONED IN EARLIER DISCUSSIONS...THE TROUGHING MIGHT BE HELD IN PLACE FOR A WHILE WITH BLOCKING PATTERN DOWNSTREAM HOLD THE PATTERN ROUGHLY IN PLACE. THE CONTINUED ACTIVE PATTERN MY CREATE SOME HYDROLOGY CONCERNS GIVEN THE RECENT WET PATTERN. && .AVIATION.../18Z TAF ISSUANCE/ A WARM FRONT EXTENDS ALONG THE MINNESOTA RIVER VALLEY AND HAS PRODUCED SEVERAL BOUTS OF CONVECTION IN EAST CENTRAL MN AND EXTREME WESTERN WISCONSIN THIS MORNING AND EARLY AFTERNOON. THESE STORMS HAVE BEEN MORE OF A HAIL THREAT THAN A WIND THREAT WITH NICKLE SIZE HAIL AND GUSTS IN THE 30KT RANGE. A COLD FRONT IS MOVING INTO WESTERN MN AT THIS TIME WITH CLEARING JUST AHEAD AND BEHIND THE FRONT. THE WARM FRONT WILL MOVE TOWARD MSP AROUND 22Z AND THE COLD FRONT/TROUGH MOVES INTO CENTRAL MN AT THAT TIME. THERE IS FAIR AMOUNT OF UNCERTAINTY AS TO HOW MUCH CONVECTION WILL DEVELOP AHEAD OF THE COLD FRONT DUE TO THE ONGOING CONVECTION FOR STC/MSP/RNH. DO NOT EXPECT TO SEE ANY SIGNIFICANT AMOUNT OF HEATING DUE TO CLOUD COVER AT THESE SITES THEREFORE TS ACTIVITY MAY NOT BE AS INTENSE. HRRR TRIES TO DEVELOP CONVECTION 19/20Z TIME FRAME AHEAD OF THE FRONT IN THE AXN AREA BUT STRUGGLES UNTIL WE GET TO THE 22/23Z TIME FRAME. BY THIS TIME CONVECTION IS LIMITED TO RNH/MSP AND SOUTHEAST OF RWF. HRRR HAS IT OUT OF THE MSP/RNH SITES BY 02Z AND OUT OF EAU BY 04Z. KMSP...TS ACTIVITY IS MAINLY SOUTHWEST OF THE FIELD AND EAST TO NORTHEAST OF THE FIELD. DO NOT EXPECT MUCH ADDITIONAL ACTIVITY UNTIL 22/23Z...AS THE FRONT APPROACHES. CONFIDENCE IS NOT REAL GOOD AT THIS TIME THOUGH. NOT SURE THE WARM FRONT WILL MAKE IT NORTH OF THE AIRFIELD BEFORE THE COLD FRONT/TROUGH ARRIVES AROUND 00Z. IF NOT WINDS IN THE TAF ARE TOO STRONG. /OUTLOOK/ FRIDAY...VFR. SATURDAY...MVFR/VFR WITH TSRA POSSIBLE. BEST CHANCES AFTN/EVN. SUNDAY...MVFR/VFR WITH TSRA POSSIBLE BUT LOW CONFIDENCE. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ CLF/DRL
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
256 PM CDT THU JUN 14 2012 .DISCUSSION... Short Term (Tonight through Saturday Night)... Gusty southeast winds have maintained rather dry conditions across the area this afternoon, while abundant sunshine has pushed temperatures into the middle and upper 80s. Meanwhile, quality moisture continues to stream north through the Plains, denoted by an increasing Cu field from Omaha-Topeka-Chanute westward. Cloud cover along an advancing cold front was enhancing differential heating from north of Omaha to Hastings, and continued afternoon heating coupled with increasing moisture is expected to lead to thunderstorm initiation within the next couple of hours. The evolution of this activity leads to considerable uncertainly locally as we head into the overnight hours. At face value, the combination of strong instability, frontal convergence and a weak mid level impulse leads to high confidence of thunderstorm initiation across the Mid Missouri Valley. As has been the case of late, deep layer shear is marginally supportive of multi-cell clusters. However, it should be noted that the bulk of the deep layer shear (20-30 kts) is focused mainly in the lowest 3-4km. Historically, these high CAPE and weak, low tropospheric shear cases have been overlooked and can often manifest themselves as long-lived organized MCS events. The NAM has been suggesting this in the mass fields for a number of runs now, and recent HRRR and other convection allowing output also side with this notion. Low level shear vectors and moisture flux vectors would suggest an overall SE momentum of any organized system(s), with an eastern limit bounded by the dry air circulating the high to our east. With that said, feel that increasing POPs is warranted both numerically and spatially across western MO and eastern KS for tonight. Severe weather, primarily in the form of wind potential, will be dictated by any upscale growth of the system and the maintenance of downstream instability into the late evening hours. This is somewhat more questionable, but the derecho that ran from srn MO to the Gulf coast back on Monday occurred in a far less suitable environment. Depending on any remnant MCV and/or surface outflow boundary, differential heating could again yield scattered thunderstorms again tomorrow afternoon, with several larger scale perturbations emanating from the central Rockies providing greater chances Saturday and Sunday. Precipitation/cloud cover will ultimately drive max/min temperature potential, so have opted to stay the course with mid-upper 80s for highs and 65-70 for lows for the bulk of the CWA as a hedge toward persistence (just above climo). Bookbinder Medium Range (Sunday through Thursday)... Tail end of the weekend will arrive with a frontal boundary sagging south into eastern Kansas and northern Missouri, pushed into our region by one of many shortwaves moving through the northern stream. GFS and ECMWF have converged some over the past couple of runs towards a common solution which pushes the late weekend frontal boundary south into Missouri during the day Sunday. However, as the front settles into Missouri the parent shortwave will be exiting the region through the Upper Great Lakes, indicating that the southerly push on the front will fade quickly. This presents the likely scenario for Sunday something like this; decaying thunderstorms may still be kicking around parts of eastern Kansas and Missouri after sunrise Sunday with it likely that any morning activity will either shift east out of the area, or fade away by the mid to late morning hours. This, however, leaves the potential for afternoon recovery of instability in the vicinity of the frontal boundary that should be wallowing around the northern half of Missouri. Of course convective debris may complicate this, but in general this has lent some confidence to the idea that rain will make an appearance across parts of the forecast area Sunday, whether it`s from the morning activity (more likely) or afternoon initiation (a little less likely). Have avoided pushing up any of the POPs for Sunday beyond the chance category as the persistently advertised surface high, which will be stretched across the eastern CONUS through the Gulf Coast, will likely impede the moisture return from the Gulf some. After Sunday, a very broad trough is advertised to have moved into the western CONUS, this will result in a slightly more southwest orientation to the flow, likely keeping temperatures above normal through the middle of the work week. As this occurs, focus for any potential precipitation will shift north, closer to the storms track of the westerlies. Have damped down any mention of POPs from Monday through the day Wednesday as a result. Wednesday night into Thursday the broad west CONUS trough should be starting to traverse the upper half of the Plains States, so have kept chance POPs in for Wednesday night and Thursday as another frontal boundary settles south. Cutter && .AVIATION... VFR conditions will continue through the afternoon hours with scattered cumulus expected to develop prior to 19Z. Winds will remain southerly at 12 to 15 knots with occasional gusts of 22-24 knots expected. Winds will lose their gusty character around 00Z and back slightly toward the south-southeast this evening. Latest numerical guidance continues to indicate thunderstorms developing along a frontal zone stretches from northeast through southwest Nebraska. Wind shear weighted in the lower atmosphere, coupled with moderate to strong instability would tend to favor the upscale growth into one or more mesoscale convective systems overnight. With a slow southeast movement/propagation anticipated, this activity (if it survives) would reach the terminals toward daybreak. A PROB30 has been included for now to handle the anticipated scattered nature of this nocturnal activity as it reaches the Lower Missouri Valley late tonight. Bookbinder && .EAX WATCHES/WARNINGS/ADVISORIES... MO...NONE. KS...NONE. && $$ WFO EAX
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1248 PM CDT THU JUN 14 2012 .UPDATE... MAIN UPDATE TO THE FORECAST WAS TO DELAY ONSET OF CONVECTION AND TO WARM HIGHS A COUPLE OF DEGREES. ADDED POTENTIAL FOR HEAVY RAIN INTO THE EVENING FORECAST. DISCUSSION... REST OF TODAY AND TONIGHT... LATEST WATER VAPOR IMAGERY AND SUBJECTIVE MORNING UPPER AIR ANALYSIS INDICATE A COUPLE OF WEAK IMPULSES MOVING ACROSS THE CENTRAL ROCKIES AND INTO THE CENTRAL PLAINS TODAY. TAIL END OF NRN PLAINS COLD FRONT HAS NOW PUSHED INTO OUR FAR NWRN CWA WHERE CONVECTION SHOULD BEGIN TO DEVELOP LATER THIS AFTERNOON. AIRMASS AHEAD OF THIS COLD FRONT CONTINUES TO DESTABILIZE WITH MOIST ADVECTION AND DAYTIME HEATING. BULK OF PREVIOUS FORECAST IS RIGHT ON TRACK BUT DID ADD MENTION OF HEAVY RAINFALL FOR TWO REASONS. THE FIRST BEING THE RICH THETA-E AIRMASS ACROSS THE REGION WITH PW`S FORECAST AROUND 1.50-1.90". THE SECOND REASON IS BECAUSE OF THE SLOW NATURE OF ANTICIPATED STORM MOTION. HPC HAS PUT THE AREA IN A SLIGHT RISK FOR EXCESSIVE RAINFALL. KERN && .AVIATION...18Z TAFS FOR KOFK...KOMA AND KLNK. MAIN FORECAST CHALLENGE IS ONSET OF CONVECTIVE ACTIVITY LATER THIS AFTERNOON AND OVERNIGHT. VFR CONDITIONS ARE EXPECTED UP UNTIL TSTM ACTIVITY MOVES OVER SITES. EXPECT GUSTY SOUTHERLY SFC WINDS TO CONTINUE UNTIL WEAKENING COLD FRONT APPROACHES. LARGE HAIL...STRONG WINDS AND VERY HEAVY RAIN ARE EXPECTED WITH THE PASSAGE OF THE TSTMS. KERN PREV DISCUSSION... /ISSUED 407 AM CDT THU JUN 14 2012/ DISCUSSION... MODELS HAVE BACKED OFF ADVERTISING FLOW BECOMING SOMEWHAT BLOCKED WITH A TROF DIGGING OVER THE WRN CONUS AND RIDGE AMPLIFYING EAST. SOLUTIONS NOW SHOWING A CUTOFF LOW FORMING OVER THE SWRN STATES BY SATURDAY MORNING WITH FAST FLOW WESTERLIES PREVAILING ACROSS THE NRN TIER STATES. FOR TODAY...SHORTWAVE TROF AND ATTENDANT SFC LOW MOVING ACROSS THE U.S./CAN BORDER WILL DRAG A COLD FRONT ACROSS THE NRN/CNTRL PLAINS AND BE THE FOCUS FOR NEXT ROUND OF THUNDERSTORM ACTIVITY. STRONG LLVL MOISTURE ADVECTION INTO THE REGION PUSH PRECIP WATER VALUES GREATER THAT 1.5"/KI AROUND 40...AND WITH DAYTIME HEATING MUCAPES CATAPULT TO 4500 J/KG. LATEST HIRES RAP AND NMM ARE ADVERTISING ACTIVITY ERUPTING AROUND 18Z ON EDGE OF WEAK CAP...JUST ON THE WRN PERIPHERY OF THE CWA. EXPECT CONVECTION WILL MORE OR LESS CONTINUE ALONG WELL DEFINE BNDRY LYR MOISTURE CONVG ZONE WELL INTO TONIGHT AND FRIDAY. BY FRIDAY NIGHT...ANOTHER SHORTWAVE TRAVERSING THE U.S./CAN BORDER WILL DRAG A COLD FRONT INTO THE CNTRL PLAINS. SMALL POPS ARE ALREADY IN PLACE THRU SUNDAY FOR THIS SO NO NEED FOR ADJUSTMENTS. OTHERWISE...APPEARS THAT SUBSEQUENT SHORTWAVES AND ATTENDANT SFC BOUNDARIES WILL KEEP AN UNSETTLED PATTERN IN PLACE THRU EARLY NEXT WEEK. DEE && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$
AREA FORECAST DISCUSSION
NWS MORRISTOWN TN
153 PM EDT THU JUN 14 2012 .AVIATION...SOME INSTABILITY NOTED ON THE RUC WITH HIGHEST DEW POINTS ACROSS SOUTHEAST TENNESSEE AND ISOLATED CONVECTION HAS FORMED MAINLY OVER THE CUMBERLAND PLATEAU AND SMOKY MOUNTAINS. PLACED A VICINITY THUNDER FOR CHA AS A STORM MAY DEVELOP NEARBY. KEPT THE OTHER TERMINALS FREE FROM PRECIP. FLIGHT CONDITIONS SHOULD REMAIN VFR THROUGHOUT THE FORECAST PERIOD WITH SLOWLY BUILDING HEIGHTS. && .MRX WATCHES/WARNINGS/ADVISORIES... NC...NONE. TN...NONE. VA...NONE. && $$
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
601 PM CDT THU JUN 14 2012 .DISCUSSION... SEE 00Z AVIATION DISCUSSION BELOW. && .AVIATION... VFR CONDITIONS ARE EXPECTED THE NEXT 24 HOURS. WATCHING TSTMS AGAIN OVER THE TRANS PECOS OF SOUTHWEST TEXAS. THESE STORMS ARE MOVING SLOWLY NORTHEAST AND REDEVELOPING ON THE SOUTHERN FLANK OF THIS COMPLEX. THE STORMS WILL REMAIN WELL WEST OF THE TERMINALS THIS EVENING. WINDS WILL BE SOUTH AT 10 TO 15 KNOTS WITH A FEW GUSTS TO 20 KNOTS. 21 && .PREV DISCUSSION... /ISSUED 333 PM CDT THU JUN 14 2012/ SHORT TERM... THIS MORNING...500MB ANALYSIS SHOWED A RIDGE AXIS STRETCHING ROUGHLY FROM FAR WEST TEXAS INTO NORTHWESTERN OKLAHOMA. FARTHER WEST...A SHORTWAVE TROUGH WAS ROTATING AROUND THE SOUTHERN SIDE OF A CLOSED LOW OVER THE SOUTHERN CALIFORNIA COAST. THERE WAS ALSO A SHORTWAVE ACROSS NORTHWESTERN NM...MOVING TO THE NORTHEAST. AT THE SURFACE... WE HAVE SOUTH TO SOUTHEASTERLY FLOW WITH SURFACE TROUGHING IN EASTERN NEW MEXICO SOUTH INTO FAR WEST TEXAS. THE SOUTHERLY FLOW IS HELPING KEEP MOISTURE IN PLACE ACROSS OUR CWA AS DEWPOINT VALUES REMAIN IN THE 60S FOR THE MOST PART...WITH KABI SITTING AT 69 DEGREES...AND KBBD AT 70 DEGREES AT 2PM. THE HOT TEMPERATURES AND HIGH DEWPOINT VALUES ARE CONTRIBUTING TO CAPE VALUES EXCEEDING 4000 J/KG OVER A LARGE PORTION OF THE CWA. THE QUESTION FOR TONIGHT WILL BE WHETHER OR NOT CONVECTION CAN GET GOING THIS AFTERNOON TO OUR WEST...AND IF IT WILL IMPACT OUR AREA. BOTH THE HRRR AND NAM ARE OPTIMISTIC IN TERMS OF RAIN CHANCES FOR THE SOUTHERN 2/3 OF THE CWA. THE HRRR DEVELOPS A BROKEN LINE OF THUNDERSTORMS BY 3 OR 4 PM LOCAL TIME...FURTHER DEVELOPING THAT INTO A SOUTHEASTWARD PROPAGATING MCS THROUGH THE REST OF THE CWA. THE NAM SHOWS A SIMILAR SCENARIO DEVELOPING QPF ACROSS THE CONCHO VALLEY DURING THE LATE AFTERNOON AND EVENING...THEN ADDITIONAL QPF FARTHER SOUTH AND SOUTHEAST DURING THE EVENING HOURS. THE GFS IS COMPLETELY DRY...AND ECMWF DOES SHOW SOME QPF...WITH THE FOCUS ALONG THE WESTERN BORDER OF THE CWA. WITH THIS IN MIND...WILL GO WITH A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS FOR GENERALLY THE WESTERN HALF OF THE CWA. CONSIDERING THE MAGNITUDE OF THE CAPE VALUES...0-6KM BULK SHEAR VALUES OF 30 TO 40 KNOTS...WE COULD EXPECT TO SEE THESE STORMS QUICKLY STRENGTHEN AND COULD SEE SOME SEVERE THUNDERSTORMS. THE MAIN HAZARD WOULD LIKELY BE WIND AS A DRY SUBCLOUD LAYER WILL RESULT IN AN /INVERTED V/ TYPE SOUNDING AND DECENT DOWNBURST POTENTIAL. THAT/S ALL DEPENDENT ON WHETHER OR NOT THUNDERSTORMS CAN DEVELOP. WHILE WE ARE ONLY GOING WITH SLIGHT CHANCE POPS AT THE MOMENT...IF CONVECTION BEGINS TO RAPIDLY DEVELOP...WE WILL LIKELY UPDATE THE FORECAST. FOR TEMPERATURES...HAVE GONE WITH A PERSISTENCE FORECAST FOR THE MOST PART. NOT EXPECTING A LOT OF PRECIPITATION...HAVE KEPT LOWS TONIGHT WARMER THAN...BETWEEN THIS MORNING/S LOWS AND THE GUIDANCE TEMPERATURES. BASICALLY WENT WITH WARMER THAN GUIDANCE FOR HIGHS TOMORROW...AS WE/VE GENERALLY BEEN WARMER THE LAST FEW DAYS...WHEN NOT EXPERIENCING PRECIPITATION. LONG TERM... FAIRLY WEAK UPPER LEVEL RIDGING TO HOLD THROUGH THE WEEKEND ACROSS THE SOUTHWEST US...WHILE A WEAK INVERTED TROUGH TRIES TO APPROACH FROM THE EAST. THIS SETS UP A WEAK SHEAR AXIS WEST OF THE AREA. THIS MAY BE ENOUGH TO GENERATE SOME CONVECTION...BUT IF IT DOES DEVELOP...IT WILL LIKELY HAVE A HARD TIME MOVING VERY FAR EAST. WILL KEEP A DRY FORECAST FOR NOW. OTHERWISE...TEMPERATURES WILL COOL JUST SLIGHTLY...AS LOW LEVEL FLOW BACKS TO THE SOUTHEAST AND MOISTURE INCREASES. HAVE BOOSTED OVERNIGHT LOWS A FEW DEGREES WITH THE MOISTURE INCREASE...WITH AFTERNOON HIGHS PRETTY CONSISTENT IN THE LOW TO MID 90S. && .PRELIMINARY POINT TEMPS/POPS... ABILENE 74 95 72 92 73 / 10 10 10 10 10 SAN ANGELO 75 97 74 95 72 / 20 10 10 10 10 JUNCTION 74 95 74 93 72 / 10 0 0 10 10 && .SJT WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
333 PM CDT THU JUN 14 2012 .SHORT TERM... THIS MORNING...500MB ANALYSIS SHOWED A RIDGE AXIS STRETCHING ROUGHLY FROM FAR WEST TEXAS INTO NORTHWESTERN OKLAHOMA. FARTHER WEST...A SHORTWAVE TROUGH WAS ROTATING AROUND THE SOUTHERN SIDE OF A CLOSED LOW OVER THE SOUTHERN CALIFORNIA COAST. THERE WAS ALSO A SHORTWAVE ACROSS NORTHWESTERN NM...MOVING TO THE NORTHEAST. AT THE SURFACE... WE HAVE SOUTH TO SOUTHEASTERLY FLOW WITH SURFACE TROUGHING IN EASTERN NEW MEXICO SOUTH INTO FAR WEST TEXAS. THE SOUTHERLY FLOW IS HELPING KEEP MOISTURE IN PLACE ACROSS OUR CWA AS DEWPOINT VALUES REMAIN IN THE 60S FOR THE MOST PART...WITH KABI SITTING AT 69 DEGREES...AND KBBD AT 70 DEGREES AT 2PM. THE HOT TEMPERATURES AND HIGH DEWPOINT VALUES ARE CONTRIBUTING TO CAPE VALUES EXCEEDING 4000 J/KG OVER A LARGE PORTION OF THE CWA. THE QUESTION FOR TONIGHT WILL BE WHETHER OR NOT CONVECTION CAN GET GOING THIS AFTERNOON TO OUR WEST...AND IF IT WILL IMPACT OUR AREA. BOTH THE HRRR AND NAM ARE OPTIMISTIC IN TERMS OF RAIN CHANCES FOR THE SOUTHERN 2/3 OF THE CWA. THE HRRR DEVELOPS A BROKEN LINE OF THUNDERSTORMS BY 3 OR 4 PM LOCAL TIME...FURTHER DEVELOPING THAT INTO A SOUTHEASTWARD PROPAGATING MCS THROUGH THE REST OF THE CWA. THE NAM SHOWS A SIMILAR SCENARIO DEVELOPING QPF ACROSS THE CONCHO VALLEY DURING THE LATE AFTERNOON AND EVENING...THEN ADDITIONAL QPF FARTHER SOUTH AND SOUTHEAST DURING THE EVENING HOURS. THE GFS IS COMPLETELY DRY...AND ECMWF DOES SHOW SOME QPF...WITH THE FOCUS ALONG THE WESTERN BORDER OF THE CWA. WITH THIS IN MIND...WILL GO WITH A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS FOR GENERALLY THE WESTERN HALF OF THE CWA. CONSIDERING THE MAGNITUDE OF THE CAPE VALUES...0-6KM BULK SHEAR VALUES OF 30 TO 40 KNOTS...WE COULD EXPECT TO SEE THESE STORMS QUICKLY STRENGTHEN AND COULD SEE SOME SEVERE THUNDERSTORMS. THE MAIN HAZARD WOULD LIKELY BE WIND AS A DRY SUBCLOUD LAYER WILL RESULT IN AN /INVERTED V/ TYPE SOUNDING AND DECENT DOWNBURST POTENTIAL. THAT/S ALL DEPENDENT ON WHETHER OR NOT THUNDERSTORMS CAN DEVELOP. WHILE WE ARE ONLY GOING WITH SLIGHT CHANCE POPS AT THE MOMENT...IF CONVECTION BEGINS TO RAPIDLY DEVELOP...WE WILL LIKELY UPDATE THE FORECAST. FOR TEMPERATURES...HAVE GONE WITH A PERSISTENCE FORECAST FOR THE MOST PART. NOT EXPECTING A LOT OF PRECIPITATION...HAVE KEPT LOWS TONIGHT WARMER THAN...BETWEEN THIS MORNING/S LOWS AND THE GUIDANCE TEMPERATURES. BASICALLY WENT WITH WARMER THAN GUIDANCE FOR HIGHS TOMORROW...AS WE/VE GENERALLY BEEN WARMER THE LAST FEW DAYS...WHEN NOT EXPERIENCING PRECIPITATION. .LONG TERM... FAIRLY WEAK UPPER LEVEL RIDGING TO HOLD THROUGH THE WEEKEND ACROSS THE SOUTHWEST US...WHILE A WEAK INVERTED TROUGH TRIES TO APPROACH FROM THE EAST. THIS SETS UP A WEAK SHEAR AXIS WEST OF THE AREA. THIS MAY BE ENOUGH TO GENERATE SOME CONVECTION...BUT IF IT DOES DEVELOP...IT WILL LIKELY HAVE A HARD TIME MOVING VERY FAR EAST. WILL KEEP A DRY FORECAST FOR NOW. OTHERWISE...TEMPERATURES WILL COOL JUST SLIGHTLY...AS LOW LEVEL FLOW BACKS TO THE SOUTHEAST AND MOISTURE INCREASES. HAVE BOOSTED OVERNIGHT LOWS A FEW DEGREES WITH THE MOISTURE INCREASE...WITH AFTERNOON HIGHS PRETTY CONSISTENT IN THE LOW TO MID 90S. && .PRELIMINARY POINT TEMPS/POPS... ABILENE 74 95 72 92 73 / 10 10 10 10 10 SAN ANGELO 75 97 74 95 72 / 20 10 10 10 10 JUNCTION 74 95 74 93 72 / 10 0 0 10 10 && .SJT WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 20/07
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
114 PM CDT THU JUN 14 2012 .AVIATION... CONCERNS...ISOLATED THUNDERSTORMS THIS AFTERNOON. MVFR CEILINGS 09-15Z FRIDAY. ISOLATED THUNDERSTORMS ARE EXPECTED TO DEVELOP MID TO LATE AFTERNOON ACROSS NORTH TEXAS. THE CAP IS ALMOST GONE ACROSS THE AREA ALONG AND EAST OF THE I-35 CORRIDOR AS OF 18Z. HAVE PLACED VCTS IN THE METROPLEX TAFS FOR THE 20Z THROUGH 00Z PERIOD. SOME LARGE HAIL AND STRONG WINDS MAY OCCUR IF THESE STORMS DEVELOP. THE CONVECTION SHOULD DIE OFF BEFORE SUNSET. SOME MVFR CEILINGS ARE EXPECTED TO DEVELOP LATE TONIGHT AND CONTINUE THROUGH MID MORNING...FOR NOW HAVE PLACED BKN018 FOR THE 09-15Z PERIOD. SOUTH TO SOUTHEAST SURFACE WINDS OF 8 TO 13 KNOTS WILL PREVAIL THROUGH THE PERIOD. 58 && .UPDATE... SCATTERED CONVECTION CONTINUES MAINLY ACROSS THE NORTHEAST...BUT RECENT RADAR RETURNS HAVE BEEN NOTED IN MONTAGUE COUNTY. THE REMNANT OUTFLOW BOUNDARY REMAINS DRAPED ACROSS THE AREA AND LATEST SURFACE ANALYSIS HAS THIS BOUNDARY ALONG A LINE NEAR BOWIE TO MCKINNEY TO CANTON. THIS BOUNDARY CAN BE IDENTIFIED BY THE SHIFT OF A SOUTHERLY WIND TO A SOUTHEAST WIND. THE 12Z FWD SOUNDING HAD 30 KNOTS OF LOW LEVEL FLOW UP TO 800 MB. THIS FLOW IS LIKELY BEING ASCENDED UP AND OVER THE BOUNDARY ENHANCING THE LOW LEVEL LIFT. THIS CAN BE SEEN ON THE THE 305K ISENTROPIC CHART. OVER THE NEXT COUPLE OF HOURS...EXPECT THIS BOUNDARY TO SHIFT NORTH AND THE LOW LEVEL JET TO WEAKEN. THIS SHOULD ALLOW FOR OUR LIFT TO DIMINISH AND A BREAK FROM THE STORMS LATE THIS MORNING AND EARLY AFTERNOON. THE HRRR IS DEVELOPING WIDESPREAD THUNDERSTORMS ALONG A SOUTHWARD MOVING BOUNDARY TODAY WITH THUNDERSTORMS INTO THE METROPLEX AROUND NOON. THE 14Z FORECAST FROM THE HRRR ALREADY SEEMS OUT OF THE LOOP AND WILL NOT GIVE MUCH WEIGHT TO ITS FORECAST. FOR THE AFTERNOON...PEAK HEATING SHOULD ALLOW FOR SOME THUNDERSTORM DEVELOPMENT ACROSS NORTH TEXAS. LOCATIONS IN THE EASTERN ZONES WILL HAVE THE BEST CHANCES WHERE THERE IS HIGHER MOISTURE. YESTERDAYS SEVERE WEATHER EPISODE WAS IN PART DUE TO MID-LEVEL WINDS OF 35-40 KNOTS ON THE BACKSIDE OF AN UPPER LOW. THESE WINDS HAVE SINCE SHIFTED EAST AND 500 MB WINDS ARE ONLY EXPECTED TO BE 10-25 KNOTS WITH THE HIGHEST WINDS IN THE SOUTHEAST. GIVEN THE HIGHER MOISTURE...25 KNOT MID-LEVEL FLOW AND ADEQUATE INSTABILITY...SOME SEVERE STORMS ARE POSSIBLE...MAINLY IN THE SOUTHEASTERN ZONES THIS AFTERNOON. HOWEVER...DO NOT ANTICIPATE LONG-LIVED SUPERCELLS LIKE YESTERDAY...AS SHEAR ISNT EXPECTED TO BE AS STRONG. 85/NH && .PREV DISCUSSION... /ISSUED 305 AM CDT THU JUN 14 2012/ ATMOSPHERE REFUSES TO STABILIZE...AS MODELS HAVE TRIED TO FORECAST FOR A COUPLE OF DAYS NOW. GUIDANCE NOW HOLDS SOME INSTABILITY AND LOW PRECIP CHANCES IN THEIR OUTPUT THROUGH THURSDAY NIGHT AND THAT IS WHAT I AM FORECASTING. FOR THIS MORNING...A WEAK BOUNDARY OR FRONT REMAINS DRAPED ACROSS NORTH TEXAS...RUNNING GENERALLY FROM PALESTINE TO EASTLAND. A FEW STORMS HAVE FIRED IN NORTHWEST COUNTIES...BUT SEEM TO BE WEAKENING. AN AREA OF CONVECTION IN THE EAST...CENTERED BETWEEN ATHENS AND FAIRFIELD...HAS BECOME LARGER IN THE LAST FEW HOURS. NO ORGANIZED SEVERE WEATHER IS EXPECTED...BUT SEVERE WARNINGS WERE ISSUED EARLIER TONIGHT FOR STORMS FARTHER SOUTHEAST NEAR CROCKETT. I HAVE ADDED SLIGHT CHANCE POPS FOR TODAY NORTHEAST OF A LINE FROM GRAHAM TO LEONA...AND CONTINUED POPS IN THE NORTHEASTERN HALF OF NORTH TEXAS THROUGH MIDNIGHT. RIDGING IS STILL PROGGED TO MOVE ACROSS THE AREA FRIDAY THROUGH MONDAY...BUT BY TUESDAY AN INVERTED TROF...EXTENDING NORTH FROM A TROPICAL DISTURBANCE IN THE GULF...WILL WEAKEN THE RIDGE AND MAY PROVIDE SOME CONVECTIVE POTENTIAL. I HAVE ADDED LOW POPS WEDNESDAY IN THE EAST AS A RESULT. WITH SOUTH FLOW EXPECTED ALL WEEK...I AM STILL FORECASTING SEASONABLY WARM TEMPERATURES...LOWS IN THE 70S AND HIGHS IN THE UPPER 80S/LOW 90S. SINCE THE RIDGE IS NOT PROGGED TO BE AS STRONG AS THE USUAL MID-SUMMER //DEATH RIDGE//...THIS SHOULD LIMIT THE INVERSION STRENGTH AND THUS THE POTENTIAL FOR VERY HIGH AFTERNOON TEMPERATURES. 84 && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 93 73 92 75 93 / 20 20 5 5 5 WACO, TX 93 74 94 73 93 / 10 10 5 5 5 PARIS, TX 90 69 90 69 89 / 30 20 10 5 5 DENTON, TX 92 71 91 73 92 / 20 20 5 5 5 MCKINNEY, TX 91 71 90 72 91 / 20 20 10 5 5 DALLAS, TX 93 74 92 75 93 / 20 20 5 5 5 TERRELL, TX 92 72 92 73 92 / 20 20 10 5 5 CORSICANA, TX 92 72 94 73 92 / 20 20 5 5 5 TEMPLE, TX 92 75 92 73 92 / 10 10 5 5 5 MINERAL WELLS, TX 94 70 91 70 91 / 20 10 5 5 5 && .FWD WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 58/85
AREA FORECAST DISCUSSION
NWS SPOKANE WA
226 PM PDT Thu Jun 14 2012 .SYNOPSIS... A progressive flow off of the north Pacific will maintain cooler than normal temperatures over the region for the next week. from time to time weak disturbances will ride this flow bringing a chance of mainly mountain showers to the area. Stronger systems with the potential for more widespread showers will arrive for the new work week. && .DISCUSSION... Tonight and Friday...The last in the recent series of relatively weak upper level short waves is transiting the region today. With a much more stable air mass and less moisture to work with this wave is much more benign with mainly thick mid level and high clouds. Still...the HRRR radar extrapolation based model suggests the potential for a few showers kicking off this evening over the northern mountains closest to the trough base dynamic region and instability area under the cool pool aloft...which will pass through southern BC tonight. Otherwise...a generally benign weather regime is expected overnight. The trough will bring a gradient push through the gaps in the Cascades and promote breezy evening conditions over the deep basin as surface high pressure builds into the area. on Friday a weak short wave ridge will become established over the region for dryer and warmer conditions...but still not up to normal temperature-wise. The ridging will effectively suppress any chance of showers even in the mountains. Friday will be a pleasant and likely mostly sunny spring day...although more like a May spring day rather than a mid-June spring day. /Fugazzi Friday night through Sunday night: The large scale flow across the Pac NW will transition to a moist zonal flow Friday night and then toward more of a troffy pattern Sunday night. We can expect a relatively tranquil weather day on Saturday followed by increasing precipitation chances Saturday night and Sunday. Throughout the period, precipitation chances will be highest across the northern and eastern mountains with mostly dry conditions expected in the lee of the Cascades and majority of the western Basin. Models have also trend significantly wetter for the Palouse and Idaho Panhandle compared to previous runs and these changes were reflected in the latest forecast. There is a very impressive and rich moisture fetch crossing into the Eastern Pacific Basin with AMSU satellite imagery indicating over an 1.50" of precipitable water near 160W. A strong westerly jet setting up between the Gulf of Alaska low and high pressure off the CA coast will transport this moisture into the region Saturday leading to increasing clouds but very small precipitation chances away from the Cascade Crest and N mtns where relatively light rainfall amounts are expected. The first signs of forcing arrive Saturday night into Sunday per all model guidance as a shortwave and associated frontal system press through the region. There are some differences noted with the strength/depth of this midlevel wave however in one form or another, there is strong agreement that a cold front will pass through the region Saturday night into early Sunday morning. Models have trend much wetter with the warm sector pcpn across NE WA and N ID btwn 00-06z where upwards of a quarter of an inch is now possible. Further investigation suggest the presence of strong 305K isentropic ascent coupled with a layer of 700-500mb negative theta-e lapse rates so the potential does exist for a burst of heavy shower activity given these conditions and moisture advecting into the region. Late Saturday night/early Sunday...the front slumps into the region...in a nw to se fashion, models have come into better agreement of showers...potentially moderate at times, setting between Ritzville and Mullan. Combined with increasing sw upsloping flow into the Central Idaho Panhandle Mtns...suggest the potential for another area of higher QPF amts which as of the 12z model runs...ranges from 0.25" on the SREF to .35" EC/NAM to .60" via the GFS over the 6 hr period between 6-12z Sunday. Given the slower arrival of a midlevel dry slot from previous runs and how juicy the upstream moisture fetch is, I would not discount the latest guidance but due to the amount of bouncing around from previous runs...I only began to show an increase in PoPs and QPF with expectations that this forecast will need to be further increased given we achieve stability in the models. The front will track east of the region early Sunday afternoon driven by a 130kt NW jet and accompanied midlevel dry slot. This will result in rapid clearing and drying away from the Cascade Crest toward the Idaho Panhandle. Low level drying will quickly cease any additional pcpn threats for points south of line from Omak to Winchester but the cooler air, on the north side of the jet, will renew the chance for convective showers and thunderstorms Sunday afternoon across NE WA and N ID. Shear will definitely be in the moderate to strong range, but less confidence holds with the model`s dewpoints and resultant fcst"d" CAPE values so tough to say exactly what mode of storms if any at all this far in advance...stay tuned. We have warmed temperatures for Saturday and cooled slightly for Sunday yielding temperatures slightly above normal to start the weekend and near normal to end. /sb Sunday night through Thursday...Models are in good agreement through Tuesday that a 120 knot jet stream will be located south of our area across Oregon. This will place Central and Eastern Washington and North Idaho on the cold and unstable side of the jet with a series of waves tracking into the area. This will result in showers both days especially in the afternoon and evening hours when the atmosphere is the most unstable. GFS and ECMWF have the best instability over the mountains of Northeast Washington and the Idaho Panhandle so a slight chance of thunderstorms was kept in the forecast. The least shower coverage will be in the lee of the Cascades due to 850mb winds of 10-20 knots downsloping off the mountains. Overall precipitation chances were increased Monday and Tuesday based on GFS Ensemble mean pops and the ECMWF solution. 850mb temperatures drop to around 7-10C resulting in high temperatures in the valleys mainly in the 60s to lower 70s which is 5 to 10 degrees below normal. On Wednesday and Thursday indications are that a ridge will begin to build with a drying and warming trend. Although some model solutions indicate a weak wave passing near the Canadian border on Wednesday so some shower activity may linger over the northern Mountains. The ridge however does not look to last long with another trough possibly impacting the Inland Northwest beyond the extended forecast period. JW && .AVIATION... 18Z TAFS: A weak upper level wave will pass through the region today but the air mass is stable and most of the associated moisture is high elevation. Thus while occasionally thick mid level and high cirrus will prevail...ceilings at all TAF sites will remain aoa 10 Kft MSL. A few afternoon showers are possible over the high terrain north of the Columbia Basin and the high Cascades. VFR conditions are expected at all TAF sites through 18z Friday. /MJF && .PRELIMINARY POINT TEMPS/POPS... Spokane 44 72 48 77 54 74 / 10 0 0 0 20 20 Coeur d`Alene 44 70 46 75 52 70 / 20 0 0 0 30 20 Pullman 43 69 45 74 52 72 / 10 0 0 0 30 20 Lewiston 51 77 52 81 58 78 / 10 0 0 0 20 10 Colville 45 78 48 80 51 77 / 20 0 0 10 20 10 Sandpoint 42 71 42 73 51 68 / 20 0 0 10 30 40 Kellogg 43 68 46 71 51 65 / 20 0 0 0 40 40 Moses Lake 49 78 54 86 58 80 / 0 0 0 0 0 0 Wenatchee 50 80 55 82 58 76 / 0 0 0 0 0 0 Omak 44 79 49 81 53 77 / 10 0 0 10 10 0 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
600 PM CDT THU JUN 14 2012 .SHORT TERM...TONIGHT THROUGH SUNDAY 242 PM CDT THU JUN 14 2012 MAIN FORECAST CONCERNS ARE ON SEVERE THUNDERSTORM CHANCES LATE THIS AFTERNOON INTO THIS EVENING ACROSS PORTIONS OF NORTHEAST IOWA...SOUTHEAST MINNESOTA...WEST CENTRAL INTO NORTH CENTRAL WISCONSIN. FOCUS THEN TURNS TO SHOWER/THUNDERSTORM CHANCES TONIGHT THROUGH FRIDAY NIGHT. WATER VAPOR IMAGERY SHOWED A POTENT UPPER LEVEL TROUGH EXTENDING FROM CENTRAL MANITOBA SOUTH THROUGH WESTERN NORTH DAKOTA INTO NORTHEAST SOUTH DAKOTA...PUSHING EAST. SURFACE OBSERVATIONS SHOWED LOW PRESSURE MOVING INTO CENTRAL MINNESOTA. A WARM FRONT WAS DRAPED ACROSS CENTRAL MINNESOTA INTO SOUTHEAST MINNESOTA. A COLD FRONT EXTENDED SOUTHWEST FROM THE LOW THROUGH SOUTHWEST MINNESOTA...FAR NORTHWEST IOWA...THROUGH CENTRAL NEBRASKA. LATEST RADAR SHOWED THUNDERSTORM ONGOING ACROSS CENTRAL INTO SOUTH CENTRAL MINNESOTA...SOME OF WHICH HAVE BEEN SEVERE THIS AFTERNOON. PLAN ON ADDITIONAL SHOWERS AND THUNDERSTORMS DEVELOP ALONG THE FRONT LATE THIS AFTERNOON INTO THIS EVENING...IMPACTING THE FORECAST...PARTICULARLY ACROSS PARTS OF NORTHEAST IOWA...NORTHEAST IOWA...INTO WEST CENTRAL WISCONSIN. THE AFOREMENTIONED UPPER LEVEL TROUGH WILL MOVE NORTHEAST TONIGHT AND HEAD FOR HUDSON BAY. THE FRONT WILL DRAG THE COLD FRONT EASTWARD TONIGHT. THE FRONT WILL SLOW AND BECOME STATIONARY LATE TONIGHT INTO FRIDAY. FORECAST MODELS ARE SHOWING SOME SLIGHT DIFFERENCES ON EXACTLY WHERE THE STATIONARY BOUNDARY WILL ESTABLISH ITSELF ON FRIDAY. THE 12Z NAM PLACES THE FRONT STRETCHING FROM NORTH CENTRAL IOWA...NORTHEAST TO NEAR WINONA MINNESOTA INTO NORTHEAST WISCONSIN. THE 00 ECMWF SHOWS THE FRONT FURTHER TO THE NORTH...STRETCHING FROM SOUTH CENTRAL MINNESOTA INTO NORTH CENTRAL WISCONSIN. THE 12Z GFS IS IN LINE WITH THE NAM. AFTER SOME EARLY MORNING SHOWERS/THUNDERSTORMS ACROSS THE AREA...CAPE VALUES ARE EXPECTED TO INCREASE ALONG THE BOUNDARY. AFTERNOON 0-3 KM MUCAPE VALUES ARE EXPECTED TO RANGE FROM 1500 TO 2000 J/KG BY MID AFTERNOON. THE NAM DEWPOINTS LOOK A LITTLE ON THE HIGH SIDE FRIDAY AFTERNOON WITH VALUES RANGING FROM 68 TO 75...SO NOT BUYING INTO THE LARGE CAPE VALUES IT PRODUCING DURING THE AFTERNOON HOURS. NOT MUCH FORCING NOTED ALOFT BUT THE STRONG INSTABILITY AND WEAK CONVERGENCE ALONG THE FRONT SHOULD BE ENOUGH TO GET THUNDERSTORMS TO INITIATE AGAIN FRIDAY AFTERNOON. SHEAR IS RATHER WEAK...WITH 0-6 KM BULK SHEAR OF AROUND 20 KTS. CANNOT RULE OUT A PULSE SEVERE STORM OR TWO CAPABLE OF PRODUCING BRIEF HEAVY RAIN...AND POSSIBLY LARGE HAIL. THE NON SUPERCELL TORNADO PARAMETER INCREASES ALONG THE BOUNDARY...1.21...DURING THE AFTERNOON HOURS...SO WILL HAVE TO KEEP A CLOSE EYE ON ANY STORMS THAT DEVELOP NEAR THE BOUNDARY. DECIDED TO INCREASE SHOWERS/THUNDERSTORM CHANCES SLIGHTLY AND SHIFT THOSE HIGHER CHANCES A LITTLE FURTHER SOUTH VS. THE PREVIOUS FORECAST. THE EARLY MORNING THUNDERSTORMS AND CLOUD COVER/ALONG WITH THE LACK OF STRONG UPPER LEVEL SUPPORT WILL LIMIT OVERALL ORGANIZATION OF THE STORMS FRIDAY AFTERNOON. LOOK FOR THE SHOWERS/THUNDERSTORMS TO DISSIPATE EARLY FRIDAY EVENING AS SURFACE HEATING DIMINISHES. 850 MOISTURE TRANSPORT IS WEAK THROUGH THE DAY ALONG THE BOUNDARY...THIS SHOULD HELP TO MITIGATE THE HEAVY RAIN POTENTIAL. ACTIVE SOUTHWEST FLOW ALOFT WILL BE IN PLACE ACROSS THE FORECAST AREA FRIDAY NIGHT THROUGH SATURDAY. THE MAIN FEATURE TO KEEP A CLOSE WATCH ON WILL BE A VIGOROUS UPPER TROUGH PUSHING THROUGH THE DAKOTAS/CENTRAL PLAINS...MOVING EAST HEADED FOR THE UPPER MISSISSIPPI RIVER VALLEY. THE STATIONARY FRONT IS EXPECTED TO LIFT NORTH AND ACT AS A WARM FRONT AS THIS FEATURE DRAWS CLOSER. A LEADING SHORTWAVE WILL EJECT OUT OF THE CENTRAL PLAINS LATE FRIDAY NIGHT AND MOVE INTO THE FORECAST AREA EARLY SATURDAY MORNING. THIS FEATURE LOOKS TO SPARK A FEW SHOWERS AND THUNDERSTORMS AS IT MOVES INTO THE AREA EARLY SATURDAY MORNING. THE MAIN TROUGH FROM THE DAKOTAS...WILL BE PUSHING INTO MINNESOTA AS THE LEADING SHORTWAVE MOVES IN. THERE IS SOME DIFFERENCES IN THE MODELS REGARDING TIMING OF THIS WAVE. THE LEADING WAVE APPEARS TO MERGE WITH THE UPPER TROUGH AS IT PUSHES INTO THE FORECAST AREA LATE SATURDAY MORNING INTO SATURDAY AFTERNOON. CAPE AND SHEAR RAPIDLY INCREASES ACROSS THE FORECAST AREA SATURDAY LATE SATURDAY MORNING INTO SATURDAY AFTERNOON. THE STRONGEST 0-6KM SHEAR LAGS SLIGHTLY BEHIND THE FRONT. SHEAR APPEARS FAVORABLE FOR STRONG TO SEVERE THUNDERSTORMS WITH 0-6 KM BULK SHEAR VALUES OF 30 TO 40 KTS. THE WARM FRONT IS EXPECTED TO LIFT NORTH INTO UPPER MICHIGAN BY MID SUNDAY MORNING WITH WARM AND MOIST SOUTHERLY FLOW IN PLACE ACROSS THE FORECAST AREA. 0-3KM MUCAPE VALUES WILL INCREASE INTO THE 1500 TO 2500 J/KG RANGE BY SATURDAY AFTERNOON. THE TROUGH WILL PUSH A COLD FRONT FROM WEST TO EAST ACROSS THE FORECAST AREA..WITH SHOWERS AND THUNDERSTORMS EXPECTED ALONG THE FRONT. THE MAIN THREATS FROM ANY THUNDERSTORMS SATURDAY AFTERNOON WILL BE LARGE HAIL AND DAMAGING WINDS. WILL HAVE TO KEEP A CLOSE WATCH ON WHERE THE WARM FRONT ENDS UP. PLAN ON HIGHS ON SATURDAY RANGING FROM THE UPPER 80S ACROSS FAR SOUTHWEST WISCONSIN TO THE UPPER 70S TO AROUND 80 ACROSS NORTH CENTRAL WISCONSIN. HOWEVER...THESE TEMPERATURES WILL BE HIGHLY DEPENDENT ON CLOUD COVER STREAMING IN FROM THE WEST AHEAD OF THE APPROACHING TROUGH. WEAK HIGH PRESSURE WILL BUILD INTO THE AREA LATE SATURDAY NIGHT INTO EARLY SUNDAY MORNING...WITH A BRIEF DRY PERIOD EXPECTED DURING THE DAY ON SUNDAY. PLAN ON PARTLY TO MOSTLY SUNNY SKIES ON SATURDAY WITH HIGHS RANGING FROM THE LOWER 80S ACROSS NORTHEAST IOWA TO THE UPPER 70S ACROSS NORTH CENTRAL WISCONSIN. .LONG TERM...SUNDAY NIGHT THROUGH THURSDAY 242 PM CDT THU JUN 14 2012 14.12 MEDIUM RANGE MODELS IN REASONABLE AGREEMENT SUNDAY NIGHT INTO MONDAY...INDICATING ANOTHER TROUGH MOVING ACROSS THE DAKOTAS/MINNESOTA PUSHING EAST INTO THE UPPER MISSISSIPPI RIVER VALLEY DURING THE DAY ON MONDAY. A MORE FAVORABLE PATTERN FOR STRONG TO SEVERE THUNDERSTORMS LOOKS TO SET UP MONDAY INTO TUESDAY AS A WARM FRONT PUSHES BACK INTO THE REGION AND SOUTHWEST FLOW ALOFT REESTABLISHES ACROSS THE AREA. THE FIRST ROUND OF SHOWERS AND STORMS APPEARS TO MOVE THROUGH SUNDAY NIGHT INTO MONDAY MORNING...MAINLY NORTH OF INTERSTATE 90 AS THE FIRST IN A SERIES OF UPPER LEVEL TROUGHS MOVE THROUGH THE AREA. A FRONTAL BOUNDARY PUSHES ACROSS THE FORECAST AREA DURING THE DAY ON MONDAY...POTENTIALLY SPARKING ADDITIONAL SHOWERS AND STORMS SOUTH OF INTERSTATE 90 MONDAY AFTERNOON. THE FRONT THEN STALLS JUST SOUTH OF THE I-90 CORRIDOR AND STARTS TO DRIFT NORTH ON TUESDAY AS A VIGOROUS TROUGH DIVES INTO THE PACIFIC NORTHWEST AND MOVES EAST TOWARDS THE NORTHERN PLAINS. PLENTY OF MOISTURE AND SHEAR TO WORK WITH DURING THIS TIMEFRAME BUT ITS DIFFICULT TO PINPOINT EXACT TIMING DETAILS THIS FAR OUT. THE ACTIVE PATTER REMAINS OVER THE REGION INTO THURSDAY AS THE TROUGH MOVES EAST TOWARDS THE GREAT LAKES. HIGH TEMPERATURES ON MONDAY WILL CLIMB WELL INTO THE 80S...WITH SOME LOCATIONS POSSIBLY APPROACHING 90 IN NORTHEAST IOWA INTO FAR SOUTHWEST WISCONSIN. PLAN ON HIGHS IN THE 80S TUESDAY INTO WEDNESDAY. WITH A SLIGHT COOL DOWN POSSIBLE ON THURSDAY IN THE WAKE OF THE TROUGH EXPECTED TO MOVE THROUGH. && .AVIATION... 600 PM CDT THU JUN 14 2012 CURRENT CONVECTION ASSOCIATED WITH WARM/COLD FRONTS ACROSS THE REGION...WITH INSTABILITY AND LOW LEVEL MOISTURE TRANSPORT FEEDING THE SHOWERS/STORMS. EXPECT A REDUCTION IN COVERAGE AND INTENSITY OF THE STORMS WITH THE LOSS OF DAYTIME HEATING. LATEST HRRR AND ARW MODEL RUNS SUPPORT THE DYING OUT OF THE SHRA/TS ACROSS THE AREA...BUT THE RAP/NAM12/GFS ALL SUGGEST THAT CONVECTION COULD CONTINUE TO FIRE IN THE VICINITY OF THE COLD FRONT. FEEL THERE IS MORE SUPPORT OF A DECREASE IN ACTIVITY AT THIS MOMENT...SO WILL STEER THE TAFS THAT WAY. HOWEVER...THE COLD FRONT LOOKS TO WAVER NORTHEAST-SOUTHWEST ACROSS THE REGION ON FRIDAY...AND WILL LIKELY SERVE AS THE FOCUS FOR MORE SHRA/TS. GREATER INSTABILITY IN THE AFTERNOON/EARLY EVENING WOULD FAVOR THIS TIME FRAME FOR MORE WIDESPREAD CONVECTION. CONFIDENCE NOT TOO HIGH ON TIMING THOUGH. ANY RIPPLE OF UPPER LEVEL ENERGY IN THE FLOW ALOFT WOULD ALSO RESULT IN SHRA/TS. EXPECT THAT TAFS WILL NEED AMENDMENTS WHEN TIMING FOR PCPN THREATS BECOMES MORE CLEAR. OVERALL...VFR CONDITIONS ARE EXPECTED OUTSIDE OF THE ANY THUNDERSTORM THAT WOULD IMPACT KRST/KLSE. && .ARX WATCHES/WARNINGS/ADVISORIES... 242 PM CDT THU JUN 14 2012 WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...WETENKAMP LONG TERM....WETENKAMP AVIATION.....RIECK
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1240 PM CDT THU JUN 14 2012 .SHORT TERM...TONIGHT THROUGH FRIDAY NIGHT 320 AM CDT THU JUN 14 2012 MAIN CONCERN WILL BE SHOWER/THUNDERSTORM CHANCES THROUGH THE PERIOD. WATER VAPOR AND RAP ANALYSIS EARLY THIS MORNING SHOW A VIGOROUS MID-LEVEL TROUGH/CLOSED LOW OVER SOUTHERN SASKATCHEWAN...EXTENDING SOUTHWARD INTO EASTERN MT. ASSOCIATED SURFACE LOW WAS OVER WESTERN SD. MOISTURE TRANSPORT/LIFT AHEAD OF THE MID-LEVEL WAVE/SURFACE LOW WAS GENERATING AN MCS THAT WAS MOVING ACROSS EASTERN ND. MEANWHILE...ANOTHER WEAKENING MID-LEVEL WAVE WAS MOVING ACROSS IA. SHRA/TS HAVE DISSIPATED WITH THIS WAVE AS THE MAIN AXIS OF MOISTURE TRANSPORT FOCUSED INTO THE ND MCS. OTHERWISE...CLOSER TO HOME...A FEW MID-CLOUD AND ANVIL DEBRIS CLOUD FROM OLD IA CONVECTION DRIFTING ACROSS THE AREA WITH TEMPERATURES AT 3 AM RANGING FROM THE MIDDLE 50S TO LOWER 60S. WILL BE KEEPING CLOSE TRACK OF THE MCS THIS MORNING...WATCHING ITS EASTWARD PROGRESS. MODELS IN GOOD AGREEMENT...TAKING THE MID-LEVEL LOW/TROUGH FROM MT INTO NORTHEAST INTO SOUTHERN MANITOBA. THIS TAKES NOSE OF MOISTURE TRANSPORT NORTHEAST WITH IT...SO EXPECTING THE MCS TO SCOOT NORTHEAST AS WELL INTO NORTHERN MN. OUR AREA WILL REMAIN ON THE EASTERN PERIPHERY OF THIS MOISTURE TRANSPORT FOR SOME ACCAS GENERATION AND ISOLATED SHRA/TS ACTIVITY. THE MAJORITY OF THIS SHOULD REMAIN NORTHWEST OF A MEDFORD/ARCADIA/ROCHESTER/AUSTIN LINE. HIGH PRESSURE OVER THE GREAT LAKES/OHIO RIVER VALLEY REGION WILL LIKELY KEEP AREAS SOUTHEAST OF THIS LINE PARTLY/MOSTLY SUNNY. OTHERWISE...PLAN ON HIGHS IN THE UPPER 70S TO THE MIDDLE 80S. FOR LATER THIS AFTERNOON...EXPECTING A LINE OF THUNDERSTORMS TO ERUPT ALONG A COLD FRONT PUSHING EAST INTO CENTRAL MN AS 0-3 MUCAPE INCREASES TO AROUND 3000J/KG AND MLCAPE INTO THE 1000-1500J/KG RANGE. AMPLE SHEAR ALSO PRESENT IN THE 25-35KT RANGE. SO...THERE IS A GOOD CHANCE FOR THIS LINE TO BECOME SEVERE. AS THE COLD FRONT/LINE OF STORMS MOVES INTO THE AREA...EXPECTING A WEAKENING TREND AS CAPE DIMINISHES AND BEST SLUG OF MOISTURE TRANSPORT SKIRTS NORTH INTO NORTHERN MN. MAINTAINED MID-RANGE SHRA/TS CHANCES FRIDAY THROUGH FRIDAY NIGHT AS AREA WILL BE SUSCEPTIBLE TO WEAK EMBEDDED WAVES IN SOUTHWEST FLOW ALOFT INTERACTING WITH DISSIPATING FRONTAL BOUNDARY. LOOKING FOR HIGHS ON FRIDAY TO TOP OFF IN THE LOW/MID 80S. .LONG TERM...SATURDAY THROUGH WEDNESDAY 320 AM CDT THU JUN 14 2012 WILL HAVE TO WATCH SATURDAY/SATURDAY EVENING CLOSELY AS MODELS SHOW A VIGOROUS MID-LEVEL TROUGH AND SURFACE COLD FRONT DROPPING SOUTHEAST INTO THE REGION. SURPRISINGLY...BOTH THE GFS AND ECMWF ONLY PRODUCE AROUND 500-600J/KG 0-3KM MLCAPE AND THIS COULD BE TIED INTO CLOUD COVER. HOWEVER IF MORE HEATING IS REALIZED...THERE COULD BE BE A SHOT AT SEVERE WEATHER GIVEN STEEPENING LAPSE RATES AND DECENT BULK SHEAR. FOR SUNDAY...LOOKS LIKE MOST OF THE AREA WILL BE DRY WITH FRONT EXITING THE AREA AND A WEAK RIDGE OF HIGH PRESSURE BUILDING IN. REST OF THE PERIOD MARKED BY A FAIRLY PROGRESSIVE/HIGH ZONAL FLOW WITH EMBEDDED WAVES. MODEL CONSENSUS YIELDS MID-RANGE SHRA/THUNDER CHANCES FOR MONDAY THROUGH WEDNESDAY WHICH SEEMS REASONABLE GIVEN THE PATTERN. HIGH TEMPERATURES EXPECTED TO AT OR A COUPLE DEGREES ABOVE NORMAL IN THE MID 70S TO MID 80S. && .AVIATION...THROUGH 18Z FRIDAY 1240 PM CDT THU JUN 14 2012 FORECAST CHALLENGE IS FOCUSED ON SHOWERS AND THUNDERSTORM CHANCES THROUGHOUT THE PERIOD. EARLY THIS AFTERNOON...CLUSTER OF STORMS ACROSS CENTRAL AND EASTERN MINNESOTA WILL MOVE EAST-NORTHEAST AND SHOULD REMAIN NORTH OF KRST/KLSE. LATER THIS AFTERNOON AND EVENING...ADDITIONAL STORMS ARE EXPECTED TO DEVELOP ACROSS SOUTHERN MINNESOTA AND NORTHERN IOWA...AND MOVE NORTHEAST...MOST LIKELY IMPACTING KRST BETWEEN 23Z AND 04Z...WITH THE POSSIBLITY MVFR CONDITIONS BETWEEN 23Z AND 02Z. AT KLSE...CONFIDENCE IS LOW ON ANY STORMS TO IMPACT TERMINAL...SO FOR NOW LEFT OUT OF TAFS. A TIGHT PRESSURE GRADIENT WILL LEAD TO CONTINUED BREEZY SOUTHERLY WINDS FOR THE AFTERNOON...WITH GUSTS UP TO 30 KTS AT KRST AND 20 KTS AT KLSE. WINDS WILL SUBSIDE AROUND SUNSET WITH LOSS OF DAYTIME HEATING. FOR THE OVERNIGHT INTO FRIDAY...BROKEN MID TO HIGH LEVEL CLOUDS WILL PERSIST WITH ADDITIONAL SHOWERS AND THUNDERSTORMS POSSIBLE FRIDAY MORNING AFTER 12Z. && .ARX WATCHES/WARNINGS/ADVISORIES... 320 AM CDT THU JUN 14 2012 WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...DAS LONG TERM....DAS AVIATION.....ZT
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1229 PM CDT THU JUN 14 2012 UPDATED AVIATION PORTION FOR 18Z TAF ISSUANCE .SYNOPSIS..LOW-AMPLITUDE BAND OF WESTERLIES IN PLACE ACRS THE NRN TIER OF THE CONUS AND SRN CANADA...WITH MEAN TROF POSN OVER THE NRN ROCKIES AND RIDGE POSN IN THE E. THAT PATTERN WL PERSIST FOR A FEW DAYS...THEN THE WESTERLIES WL STRENGTHEN AND LARGE SCALE AMPLIFICATION WL OCCUR. BY EARLY NEXT WEEK...THERE SHOULD BE A BROAD BUT FAIRLY STG UPR TROF CENTERED OVER THE NRN ROCKIES OR NRN PLAINS...WITH A DOWNSTREAM RIDGE OVER THE ERN CONUS. THOUGH DAILY TEMPS WL VARY DUE TO CLOUD COVER WITH THE PASSAGE OF INDIVIDUAL SHRTWVS/FRONTAL SYSTEMS...TEMPS WL REMAIN ABV NORMAL FOR MUCH OF THE FCST PERIOD. A COOL DOWN IS POSSIBLE LATE IN THE PERIOD OR JUST BEYOND IF THE MEAN TROF AXIS EDGES E AS NOW INDICATED. THE PATTERN LOOKS MORE FAVORABLE FOR PCPN THAN WHAT WE/VE BEEN IN FOR THE PAST COUPLE WEEKS. OF COURSE...ACTUAL PCPN AMNTS WL DEPEND ON THE TRACK OF INDIVIDUAL CONVECTIVE SYSTEMS THAT REMAIN UNKNOW AT THIS POINT. && .SHORT TERM...TDA/TNGT/FRI. ISSUES WITH THE POTENTIAL FOR CONVECTION TO SPILL OVER INTO THE FCST AREA ARISE EARLY AND THEN CONT FOR THE REST OF THE PERIOD. PRETTY IMPRESSIVE TSTM COMPLEX OVER ERN ND/NERN SD. IT/S BEING FED BY INSTABILITY AXIS STILL WELL W OF THE FCST AREA. MOST OF THE GUIDANCE TAKES THE COMPLEX NE AND WEAKENS IT DURING THE DAY...THOUGH THE RUC BRINGS IT E THEN TURNS IT DUE S ACRS MN...DIRECTLY INTO THE LOW-LEVEL INFLOW. SOME MOISTURE CONVERGENCE NOTED ON LOCAL MESO PLOTS OVER SRN MN...AND RADAR TRENDS SEEM TO FIT THE RUC. GET THE FEELING THIS IS GOING TO BE ONE OF THOSE SITUATIONS WHERE IT/S A WASTE OF TIME TRYING TO TRY AND TRACK THE FEATURE USING THE GUIDANCE AND SIMPLY KEEPING AN EYE ON THE RADAR MOSAIC LOOP AND USING EXTRAPOLATION IS GOING TO WORK BETTER. AS SUCH...NEED TO KEEP POPS OVER THE WRN PART OF THE FCST AREA TDA...AND PROBABLY CAN/T BE TOO SPECIFIC WITH TIMING AS ONGOING STORMS COULD GET THERE BEFORE NOON IF THEY HOLD TOGETHER. OVERALL TREND HOWEVER HAS TO BE FOR STORMS TO WEAKEN SIGNIFICANTLY AS THEY GET FARTHER E...AND FOR THE POTENTIAL FOR RE-DEVELOPEMENT FARTHER E TO BE GREATLY LIMITED BY INFLUX OF DRY AIR CIRCULATION BACK OUT OF DEPARTING ANTICYCLONE. PRETTY MUCH THE SAME STORY FOR TONIGHT AND FRI. SHRA/TSRA WL GRADUALLY START TO EDGE E AS COLD FRONT TRAILING FM CYCLONE LIFTG TOWARD HUDSON BAY WORKS TOWARD THE RGN. BUT THE FRONT WL START TO SLOW AND WEAKEN AS IT GETS TO THE FCST AREA AS IT/S PARENT CYCLONE PULLS OFF TO THE NE. DRY AIR FM DEPARTING ANTICYCLONE WL CONT TO FEED DRY AIR INTO ERN WI. MAIN FCST CHG WITH THIS ISSUANCE WAS TO TRIM POPS OVER THE SERN PART OF THE FCST AREA. ALTHOUGH IT NOW LOOKS LIKE E-C WI WL STAY DRY THROUGH FRI...WAS NOT COMFORTABLE TOTALLY PULLING POPS OUT FOR MOST OF THAT AREA. SO BACKED DOWN FM WHAT WE HAD GOING...AND WL ALLOW LATER SHIFTS TO REMOVE IF CURRENT TRENDS CONTINUE. WARMER AIR WL BE RETURNING TO THE AREA ON SLY WINDS. THE BEST PERFORMING GUIDANCE WAS VERY WARM OVER E-C WI ON FRI...PROBABLY DUE TO A LACK OF PCPN. IT/S A TRICKY FCST...BECAUSE IF THERE ARE MORE CLDS WE WON/T WARM AS MUCH. STILL...TRENDING TOWARD A DRIER FCST SUGGESTED THE NEED TO GO WITH THE WARMER MAXES. .LONG TERM...FRIDAY NIGHT THROUGH NEXT THURSDAY. FORECAST CONFIDENCE LOW WITH CHALLENGING EXTENDED FORECAST. WILL BE DIFFICULT TO MAKE ANY NOTABLE ADJUSTMENTS TO PREVIOUS FORECAST AS MODEL CONCENSUS INDICATE SEVERAL DISTURBANCES...IN INITIALLY BAGGY WESTERN US TROUGH...WILL TRY AND RIDE UP THE WESTERN PERIPHERY OF STUBBORN MEAN RIDGE OVER THE EASTERN CONUS. MEDIUM RANGE MODELS OFFER A VARIETY OF SOLUTIONS WITH RESPECT TO TIMING AND INTENSITY OF EMBEDDED DISTURBANCES AS WELL AS DIFFER ON EVOLUTION OF DOWNSTREAM RIDGE. INHERITED AT LEAST CHANCE POPS EACH DAY OF THE EXTENDED AND SEE NO CLEAR SIGNAL IN THE LATEST SUITE OF MODEL RUNS TO JUSTIFY MAKING ANY SIGNIFICANT CHANGES. LATEST GEM DID SUGGEST THAT POSSIBLE MCS COMING OUT OF IOWA FRIDAY NIGHT WOULD NOT GET INTO THE SOUTHWEST PART OF WISCONSIN UNTIL AFTER 12Z SATURDAY AND WOULD AT BEST CLIP OUR SOUTHERN COUNTIES SATURDAY MORNING...WHILE OPER GFS WAS MUCH QUICKER AND FURTHER NORTH. ECMWF AND GEM SUGGESTED THERE COULD BE VERY LITTLE IN THE WAY OF PRECIPITATION IN THE FORECAST AREA FRIDAY NIGHT. DID TRIM BACK POPS SOME DURING THIS PERIOD...BUT REMAINED IN THE CHANCE CATEGORY OVER THE SOUTHWEST PORTION OF THE FORECAST AREA. ALSO LOWERED POPS SOME ON SUNDAY NIGHT AS IT APPEARS THERE COULD BE A BREAK IN PRECIPTATION BEHIND INITIAL DISTURBANCE. WILL LET LATER FORECAST SHIFTS TRY AND PROVIDE A BIT MORE RESOLUTION WITH LATER MODEL FORECASTS. PRETTY MUCH LEFT REMAINDER OF EXTENDED AS INHERITED AND RETAINED CHANCE POPS THROUGH NEXT WEDNESDAY WITH RATHER ACTIVE SOUTHWEST FLOW WITH SEVERAL DISTURBANCES FORECAST TO IMPACT THE WESTERN GREAT LAKES REGION. STUCK WITH MODEL BLEND FOR TEMPS AS TOO DIFFICULT TO RESOLVE TIMING OF INDIVIDUAL DISTURBANCES AND THEIR ASSOCIATED PRECIP AND CLOUD COVER. && .AVIATION...VERY TRICKY FCST OVER THE NXT 24 HOURS AS ONE CLUSTER OF TSTMS IN THE PROCESS OF DYING OVER CNTRL WI (FARTHER EAST THAT ANTICIPATED) WITH MORE TSTMS DEVELOPING ACROSS MN AHEAD OF AN ADVANCING CDFNT. WHILE VFR CONDITIONS WL PREVAIL OVER ERN WI WITH DRY AIR HANGING ON...PERIODS OF MVFR CIGS/VSBYS ARE POSSIBLE OVER THE RHI...AUW AND CWA TAF SITES THIS AFTERNOON AND AGAIN LATER TNGT. HAVE ALSO INCLUDED LLWS IN THE TAFS TNGT AS WINDS JUST ABOVE THE SFC TO RESIDE IN THE 30-35 KT RANGE. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ AK