Area Forecast Discussion
Issued by NWS State College, PA

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557 FXUS61 KCTP 110328 AFDCTP Area Forecast Discussion National Weather Service State College PA 1028 PM EST Sun Dec 10 2017 .SYNOPSIS...
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A clipper system will pass through on Monday night and Tuesday. Arctic air will enhance lake effect snow and may produce dangerous snow squalls on Tuesday as the best push of cold air moves through. Gusty winds along with the bitterly cold air will result in wind chills below zero over the Alleghenies by Wednesday.
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Wind more westerly now across western half of LE, and this should push some snow into the NWrn Cos shortly. All is well. Prev... Strong but fast moving short wave trough/vort max will pass overhead tonight. There is almost no moisture associated with this feature but it is picking up a little from the lakes. It`s moving so fast that it won`t affect the area for long. So, only a dusting is expected in most places with an inch in the NW mtns. At least partial clearing should occur in the wake of the trough for the SE third of the area but clouds linger in the cold air behind the trough. Mins will be a little milder than normal in the NW due to the clouds, but the clearing and snow pack in the far SE could allow them to drop off quite nicely toward sunrise. Going for M20s there for the time being, but can see those numbers dropping if clearing looks more promising.
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&& .SHORT TERM /8 AM MONDAY MORNING THROUGH 6 PM MONDAY/... Surface ridge will briefly track across the region Monday, supplying fair weather for most of the forecast area. Next in series of clippers will approach late in the day, perhaps spreading some light snow into the northwest counties before dark. && .LONG TERM /MONDAY NIGHT THROUGH SUNDAY/... All model guidance tracks clipper north of Pa Monday night, which should keep the most substantial snow north of Pa. However, blend of latest guidance still supports a likely period of light snow across central Pa, with accums generally in the 1-3 inch range. The coldest air of the season is forecast to arrive behind this system with a shot of arctic air and more lake effect snow lasting through midweek. WPC graphics indicating about a 30 pct chance of exceeding winter storm criteria across the snowbelt of Warren County Tue into Wed AM, so will highlight this potential in the HWO for now. Tight pressure gradient will result in gusty winds to accompany the arrival of the cold air. A quick look at model data suggests wind advisory criteria is possible early Wed, as large scale subsidence and pressure fall/rise couplet moves through. Med range guidance indicates another clipper is likely to affect the area late Thursday with another potential light snowfall. After that, ECENS and GEFS both indicate upper trough will lift out, resulting in a marked warm up next weekend. Latest EC ensemble MOS guidance indicating temps returning to near or slightly above climo by next weekend. && .AVIATION /04Z MONDAY THROUGH FRIDAY/... Lake flow will keep snow showers over the KBFD terminal off and on through the overnight and early morning hours. Restrictions will mainly be MVFR, though brief IFR visibility restrictions (1SM to 2SM) are possible, mainly between 09Z to 12Z. Mainly VFR conditions are forecast elsewhere, with a scattered to broken deck between 5000 and 12000 feet. Winds will be westerly at 5 to 10 knots. Outlook... Mon...Cig reductions likely western portions. PM light snow developing, mainly northwest Pa. Mon night and Tuesday...Periods of light snow. Widespread MVFR likely, with periods of IFR and brief LIFR cigs and vsbys. Wed...Reductions poss west in sct snow showers. Otherwise VFR. Thu...Still a chance of a few snow showers. && .CTP WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...Dangelo/Steinbugl NEAR TERM...Dangelo SHORT TERM...Fitzgerald/Martin LONG TERM...Martin AVIATION...Ceru is the U.S. government's official web portal to all federal, state and local government web resources and services.