Area Forecast Discussion
Issued by NWS State College, PA

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000 FXUS61 KCTP 012256 AFDCTP Area Forecast Discussion National Weather Service State College PA 556 PM EST Mon Mar 1 2021 .SYNOPSIS... March 2021 coming in like a lion. An arctic blast to kick off meteorological spring will drive potential for snow squalls across the western and northern Alleghenies later this afternoon through the evening commute. Conditions will turn sharply colder tonight with blustery northwest winds sending temperatures plummeting into the low teens and 20s with single digit wind chills. The rest of the first week of March looks mainly dry with moderating temperatures through midweek followed by a cooling trend into the weekend. && .NEAR TERM /THROUGH TUESDAY/... In the wake of this mornings leading cold FROPA, a secondary arctic front pushing southeast from the lower Great Lakes will bring the potential for isolated brief snow squalls across the northern and western Alleghenies between 4 and 10 PM. The primary areas of concern are along and north of I-80 and along and west of I-99. CIPS guidance has been bullish on SNSQ potential for the last 2 days so we are ramping up risk communication/DSS messaging heading into tonight. Flash freeze threat is also relatively high given sharply falling temps and residual road treatments washed away by recent rainfall. Blustery winds from the NW with peak gusts over 40mph will deliver a sharply colder airmass into CPA tonight. Temps will fall about 15 to 30 degrees from todays highs and bottom out in the low teens and 20s by daybreak Tuesday. Wind chills are forecast to reach the single digits in most areas with subzero readings most likely across the northern tier. Overall, a rather frigid start to the end the first day of meteorological spring. && .SHORT TERM /TUESDAY NIGHT THROUGH 6 PM TUESDAY/... After a very cold start, expect a fair and seasonably cold day on Tuesday with max temps 5 to 10F degrees below daily climo. Plenty of sunshine and subsiding winds will be provided courtesy of high pressure building into the area from the Ohio Valley. && .LONG TERM /TUESDAY NIGHT THROUGH MONDAY/... By Wednesday, a southern stream wave of low pressure will stay well south of the Commonwealth, with dry conditions persisting but some high clouds filtering the sunshine. Southwesterly flow will help push temperatures into the low 50s across the south central mountains. Latest ECENS and GEFS guidance support a deepening trough over the northeast through the weekend, with a trend toward increasingly below-average temperatures, breezy conditions, and continually dry conditions for Pennsylvania. Westerly to northwesterly flow will continue to reinforce the 5F to 10F below normal airmass. With very little moisture to tap into, any precipitation will be confined to lake-effect snow showers in the northwest mountains. Since Lake Erie is almost fully iced over in the preferred source region, sufficiently cold 850mb temps are more difficult to find. As such, have kept PoPs quite low and focused on best potential on Saturday with coldest temps aloft and northwesterly flow. By Sunday, milder temperatures are on our doorstep, with potential for a ridge of milder air to settle in. The persistence of the upper trough combined with the potential for cold air damming to persist could temper our hopes for mild conditions, but optimism reigns supreme following the seemingly never-ending stretch of winter weather. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/...
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Blustery west-northwest /290-310 degrees/ wind gusts 25-35kts will impact CPA airspace through tonight. A secondary cold front will sweep through the region early this evening, accompanied by snow showers and brief IFR vsby in a few locations across the Allegheny Plateau. Moisture streaming off of the Grt Lks is likely to produce occasional MVFR cigs over northwest Pa (KBFD) later tonight and possibly over the Laurel Highlands. Elsewhere, downsloping flow should yield VFR conditions over the rest of the area tonight. Expect diminishing winds Tuesday, as high pressure builds into the state. There could be some lingering MVFR cigs across northwest Pa (KBFD) during the morning. Otherwise, model soundings and SREF/HREF prob charts support a high confidence of VFR conditions. Outlook... Wed-Sat...VFR/no sig wx.
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&& .HYDROLOGY... Hydro response is on the decline with most streams and creeks in receding mode. The latest stage at Confluence has dropped below minor flood stage and will be canceling the warning. Other streams in the Juniata and Lower Mainstem Susquehanna tribs crested near or just over action stages and will continue falling through tonight. && .CLIMATE... Closing the books on winter season 2020-2021. Prelim data shows Harrisburg finished as the 28th snowiest on record with a total of 36.0 inches or +11.3 inches above the 30-year average. Total snowfall at Williamsport ranked as the 8th snowiest winter with 53.8 inches or +26.1 inches above the long term mean. Monthly and seasonal climate summaries will be issued in the next day or so. && .CTP WATCHES/WARNINGS/ADVISORIES... Wind Advisory until 10 AM EST Tuesday for PAZ028-037-041-042- 046-049>053-056>059-063>066. Wind Advisory until 7 AM EST Tuesday for PAZ005-006-010>012- 017>019-024>027-033>036-045. && $$ SYNOPSIS...Steinbugl NEAR TERM...Steinbugl SHORT TERM...Steinbugl LONG TERM...Lambert/Banghoff/Travis AVIATION...Fitzgerald/Evanego HYDROLOGY... CLIMATE... is the U.S. government's official web portal to all federal, state and local government web resources and services.