Area Forecast Discussion
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000 FXUS61 KPBZ 280540 AFDPBZ AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE PITTSBURGH PA 140 AM EDT TUE OCT 28 2014 .SYNOPSIS... A LATE DAY COLD FRONT WILL BRING A PERIOD OF SHOWERS TO THE REGION. COOL HIGH PRESSURE IS EXPECTED FOR MID WEEK. && .NEAR TERM /THROUGH TODAY/... OVERNIGHT PERIOD LOOKS IN GOOD SHAPE. JUST SOME MINOR ADJUSTMENTS TO CLOUD COVER AND TEMPS. UPPER LEVEL RIDGE WILL BEGIN TO BREAK DOWN THIS MORNING AS DEEP 50H LOW MOVES ACROSS THE NORTHERN GREAT LAKES. SURFACE LOW WILL BE MOVING JUST AHEAD OF UPPER LEVEL LOW WITH THE TRAILING COLD FRONT PUSHING THROUGH THE UPPER MIDWEST. COLD FRONT WILL REACH THE WESTERN HALF OF MY FORECAST AREA LATE THIS AFTERNOON BRINGING WITH IT WIDESPREAD SHOWER ACTIVITY. AHEAD OF THE FRONT...MIXING HEIGHTS WILL RISE...TAPPING INTO THE STRONG WINDS ABOVE THE SURFACE. SOME MINOR DIFFERENCES IN MODEL SOLUTIONS HERE...BUT WIND GUSTS OF 35 TO 40MPH ARE POSSIBLE AHEAD OF THE BOUNDARY. WILL CONTINUE THE MENTION OF THUNDER WITH FRONTAL PASSAGE. SURFACE INSTABILITY REMAINS INSIGNIFICANT...BUT WITH SURFACE TDS RISING TO NEAR 60 AND STRONG LOW LEVEL FORCING AND MOISTURE CONVERGENCE ACCOMPANYING THE FRONT...CONVECTION CANNOT BE RULED OUT. MODELS ARE HINTING AT THE POTENTIAL FOR ELEVATED CONVECTION WITH FRONTAL PASSAGE. IF STORMS CAN DEVELOP...THERE WILL BE PLENTY OF SHEAR AVAILABLE FOR ACTIVITY TO SUSTAIN ITSELF. STRONG WIND GUSTS WOULD BE POSSIBLE WITH ANY CONVECTION WITH A POTENT WIND FIELD ALOFT. WARMER AIR AT THE SURFACE WILL SURGE NORTHWARD PUSHING TEMPS TO WELL ABOVE NORMAL LEVELS. && .SHORT TERM /TONIGHT THROUGH THURSDAY/... COLD FRONT WILL RUSH THROUGH THE EASTERN HALF OF THE REGION THIS EVENING. WILL CONTINUE WITH THE MENTION OF THUNDER UNTIL FRONT PASSES. SHOWERS WILL END QUICKLY BEHIND THE BOUNDARY...AS A DRY AIR MASS WILL ACCOMPANY THE ENSUING CAA. STRONG CAA WILL CONTINUE INTO WEDNESDAY...RETURNING TEMPS TO MORE SEASONABLE LEVELS. EXPECT SOME SUN WEDNESDAY AS THE FLOW WILL BE JUST SOUTHWEST OF WEST AHEAD OF THE MAIN SHORTWAVE TROUGH. SHORTWAVE TROUGH WILL CROSS WEDNESDAY NIGHT PULLING THE MAIN COLD POOL OVER THE UPPER OHIO VALLEY. EXPECT A STRATOCU SHIELD TO ACCOMPANY THIS COLD AIR ALOFT. THURSDAY SHOULD BE DRY WITH SURFACE HIGH OVER THE MIDWEST. BUT DO EXPECT PLENTY OF CLOUD COVER AND CHILLY TEMPS WITH THE COLD AIR HANGING AROUND AND AN 850MB FLOW OUT OF THE NORTHWEST. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... MODELS ARE IN PRETTY GOOD AGREEMENT WITH THE TIMING OF THE NEXT SYSTEM FRIDAY. SHOWERS EXPECTED TO RETURN TO THE AREA WITH THE PASSAGE OF THE FRONT...WITH SNOW SHOWERS POSSIBLE FRIDAY NIGHT/SATURDAY MORNING IN THE MUCH COLDER AIR BEHIND THE SYSTEM. THERE ARE STILL TIMING ISSUES ON HOW FAST THE COLD AIR WILL CROSS THE AREA. COLD DAY SATURDAY WITH PLENTY OF CLOUDS AND MORNING SNOW SHOWERS POSSIBLE. CANADIAN HIGH BUILDS IN SUNDAY ALLOWING FOR DRY CONDITIONS AND MODERATING TEMPS FOR THE REMAINDER OF THE LONG TERM. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/...
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FORECAST LOW LEVEL WIND SHEAR IS ONGOING AT THIS TIME...WITH 45-50KT LOW LEVEL JET JUST A COUPLE THOUSAND FEET UP. THIS WILL CONTINUE OVERNIGHT UNTIL 14/15Z...WHEN MIXING WILL START TO BRING 25-30KT GUSTS TO THE SURFACE. VFR OTHERWISE WITH MID/HIGH CLOUDS THROUGH THAT TIME. COLD FRONT WILL MAKE ITS APPROACH LATER THIS AFTERNOON. STILL A LITTLE FAR OUT TO TRY TO TIME ANY MVFR/IFR RESTRICTIONS...WHICH ARE CERTAINLY POSSIBLE...BUT TRIED TO HINT AT THIS WITH ARRIVAL OF 6SM SHRA. ADDED VCTS FOR SEVERAL TERMINALS...ALTHOUGH CONFIDENCE IS NOT TOO GREAT PRESENTLY GIVEN RELATIVE LACK OF INSTABILITY. FROPA OCCURS BY 06Z FOR KPIT/KAGC ON WEST...WITH PARTIAL CLEARING. OUTLOOK.../TUESDAY NGT THROUGH SATURDAY/... RESTRICTIONS COULD CONTINUE FOR A BRIEF TIME AFTER 06Z TONIGHT PRIOR TO/DURING FROPA. MORE RESTRICTION POTENTIAL WL COME WITH A FRIDAY CDFNT.
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&& .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...NONE. WV...NONE. && $$

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