Area Forecast Discussion
Issued by NWS State College, PA

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000 FXUS61 KCTP 222350 AFDCTP Area Forecast Discussion National Weather Service State College PA 750 PM EDT FRI JUL 22 2016 .SYNOPSIS... Pennsylvania will be on the northern edge of the subtropical ridge into next week. A series of weakening cold fronts will bring the mention of mainly afternoon or evening showers or thunderstorms in the forecast, but most of the time it will be fair, very warm and generally dry. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... The last of the MCS is moving through my far swrn zones while continuing to dwindle. Skies are clearing rapidly in the wake of the dying showers. Over the far north there are signs of new cu formation while a more general area of strato-cu advects off Lake erie over nwrn Pa. The big question for the remainder of the day will be how much new activity can fire with diurnal heating. RAP meso anal depicts 700mb temps of 9-10C already in place with continued warm advection in progress. Local experience has associated 700mb temps of 8C or higher with being a pretty effective cap in the absence of strong forcing. For this reason I think any new convection, if any, that develops will remain fairly isolated. SPC has an area of MRGL risk for severe weather from Pa and western NY west through the Ohio Valley and beyond. My far nern zones are covered with a Slight risk as they are under slightly cooler mid level temps and modestly better shear associated with the parent shortwave that is sliding off to the north and east. With region-wide CAPEs expected to be in the 1500-2000j range, any storm that does manage to break the warm mid level cap will be capable of producing a downpour and strong wind gusts. 8h temps rising to near 20C should translate to max temps ranging from the m/80s over the Alleghenies, to between 90 and 95 elsewhere. The heat, combined with rising dewpoints, should result in widespread heat indices in the 90s. A muggy night is in store over most of the region with any convection that forms this afternoon expected to fade quickly early this evening, leaving a mainly dry overnight. Overnight lows will average around 10 deg above normal. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH 6 PM SATURDAY/... 3H weather, hazy-hot and humid, is in store for Saturday. With the warm air aloft and a weak surface high in the low levels, it will be a dry day with plenty of sunshine, a great day for the pool or lake, but no relief for agricultural interests badly in need of rain. Highs will be well above normal, ranging from the mid 80s over the NW to mid 90s over the SE. && .LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/... Big story in the extended fcst is expected heat wave lasting into early next week, as axis of subtropical ridge briefly shifts from the plains to the northeast conus. Anomalous upper lvl ridging building over PA should bring hot and mainly dry wx this weekend, as warm temps aloft suppress convection. Next chance of shra/tsra for most of the area comes Monday ahead of shortwave working across the Great Lakes. However, any rainfall Monday is likely to do little to stem the dry pattern we have been in. Latest GEFS mean qpf is up to a half an inch at most. 12Z ECENS/NAEFS mean 8h temps are near 22C Saturday through Monday, indicating the potential of several days in a row with highs in the 90s in the valleys. The hottest temps look to be on Saturday as latest GEFS gives high temperature anomalies in the +4 standard deviation and have slightly backed off on Sunday. Have adjusted Max temperatures accordingly. Heat indices around 100F appear possible by Mon across the Susq Valley, as higher dewpoints are advected into the area ahead of potential convection. Overnight lows are also a concern as the area doesn`t cool off at night through the weekend with Southern PA lows in the 70s with highest readings Monday morning. Some modest cooling appears likely by Tue/Wed of next week behind weak cold front. However, temps still likely to remain somewhat abv normal within a generally zonal flow. Midweek weather looks dry again, with just low pops for isolated tstms. Fri looks to be the next higher chance for tstm impacts areawide as another cool front progged to move through. && .AVIATION /22Z FRIDAY THROUGH WEDNESDAY/...
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Generally VFR conditions over the next 48 hours will only be punctuated by some areas of MVFR fog which is expected across central and northwestern airfields overnight tonight and again on Saturday night...mainly between 08z and 13z. While no organized precipitation is expected over the weekend, localized restrictions are possible Sunday with an isolated TSRA. OUTLOOK... SUN...Early morning fog possible...otherwise VFR with an isolated TSRA possible north. MON-TUE...Scattered restrictions possible with a cold front bringing scattered showers and thunderstorms. WED...No sig wx.
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&& .CTP WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...La Corte NEAR TERM...La Corte SHORT TERM...La Corte LONG TERM...RXR AVIATION...Jung/La Corte

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