Area Forecast Discussion
Issued by NWS State College, PA

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316 FXUS61 KCTP 270005 AFDCTP Area Forecast Discussion National Weather Service State College PA 805 PM EDT Mon Sep 26 2016 .SYNOPSIS... A cold front with a line of showers will sweep through the region overnight. A developing deep cut-off low will bring cool cloudy weather into the region late Wednesday and into early this weekend. The deep cold air should trigger showers Thursday through most of the coming weekend before it slowly begins to lift out. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... Forecast has not changed much in the HRRR and NCEP models. The front is a bit slower and there is a lead band of showers/isolated thunder in western PA now. The cold air damming in central areas has held on well and the cool stable air remains to the east. Showers will move into western areas over the next few areas with main area to the west still just entering PA. The unforecast lead band in southwest PA could bring a shower to Clearfield-Cambria and Somerset in the next 1-3 hours well ahead of the larger scale band of rain. HRRR pretty much, the the GEFS, has a 3 hour window for most areas of rain and exists all the rain 0.10 or more rainfall to our east in the 06 to 09Z rain. Some lingering light stuff in extreme east probably a bit later than 09Z. Dry air behind front should clear it out. Do not expect lingering low clouds and fog behind this front. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/... Sunny breezy day some clouds especially in mountains. Probably the best day of the week. No real anticyclone behind front due to building trough to our west and wave along the coast. But -1sigma PW and 6-10C 850 mb temperatures imply a pleasant early autumn day. It could be breezy a few hours after sunrise and the winds should diminish in the late afternoon. My bet is the statewide is the best day of the week as the cut-off is going to make things ugly by Wed-Thu. && .LONG TERM /TUESDAY NIGHT THROUGH MONDAY/... Big change in the weather pattern will set up with a long wave trough and a cut off low dropping down over the Eastern U.S. and several days with rain in the forecast. Tuesday night into Wednesday morning will see some drying and seasonable temperatures behind the cold front. But a large upper level low is dropping southeast across the Great Lake Region. By Wed afternoon the upper low is over Ohio and moisture is being pulled back north along the Eastern Coast into PA. Chances for rain showers will increase Wed afternoon with periods of rain showers likely Wed night into Thurs night as the low continues south into Western VA. Friday the low begins to shift back to the northwest continuing the wet pattern into Saturday. Models hint that Central PA may be dry slotted for a bit friday afternoon and night. Upper low begins to lift northeast Saturday into Monday with gradually decreasing POPs. Lower Susq will be driest over the weekend and dry Monday with increasing chances farther north across the higher terrain of the northern tier where chances will linger into Monday morning. Temperatures will be a little milder at night but cooler during the day with clouds and periods of showers thereby averaging around normal. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... South-southeasterly flow ahead of a cold front has brought widespread MVFR with areas of IFR to the region. Expect continued reduced conditions throughout the evening and into the overnight before drier air begins moving in behind the cold front Tuesday morning. Any improving conditions after midnight will probably just set the stage for the development of fog so earlier confidence in clearing is now not so high. Tuesday will start with most areas still experiencing MVFR/IFR, but drier air on a gusty NW breeze will lead to rapidly improving conditions in the few hours just after sunrise. Wed should be the last good VFR day before more showery and cloudy conditions develop later in the week into the weekend with widespread reduced conditions likely. Outlook... Wed...Showers/cig reductions possible late. Thu-Sat...Sct showers/cig reductions possible, esp w mountains. && .CTP WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...Grumm NEAR TERM...Grumm/Ceru SHORT TERM...Grumm LONG TERM...Watson AVIATION...La Corte is the U.S. government's official web portal to all federal, state and local government web resources and services.