Here is the latest Area Forecast Discussion for Central PA
This text statement is the latest forecast reasoning from the NWS in State College, PA
See the links at the bottom of the page for previous issuances/versions of the statement as well as our other text statements.
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047 FXUS61 KCTP 221243 AFDCTP Area Forecast Discussion National Weather Service State College PA 743 AM EST Sun Feb 22 2026 .WHAT HAS CHANGED... * A significant and widespread winter storm will bring heavy snow amounts to a large portion of Central Pennsylvania today into Monday. * Winter Storm Warnings have been expanded and now cover the Central and Southern Mountains, the Laurel Highlands and the Lower Susquehanna Valley. && .KEY MESSAGES... 1) Heavy snowfall is expected today into Monday over practically all of the Southeast half of Pennsylvania. 2) A high degree of uncertainty remains with expected snowfall over the rest of northern PA. 3) Ice jam risk continues into the weekend, but no significant flooding is expected. && .DISCUSSION... KEY MESSAGE 1: Heavy snowfall is expected today into Monday over practically all of the Southeast half of Pennsylvania. Confidence continues to increase in an area of low pressure rapidly developing off the east coast today as a very dynamic upper trough digs southeast from the Great Lakes region and amplifies across the Central Appalachians and Mid Atlantic Coast. The latest 00z Sunday guidance continues to come into good agreement on the position and strength of the coastal low as it strengthens/bombs out as its heads from the Outer Banks late this morning NNE to about 125NM east of KSBY this evening. GEFS Ensemble Plumes and their respective anomalies of various parameters show a well-defined inverted trough over Central PA today, extending NWWD from the aforementieond coastal low. This trough is at the western edge of a highly anomalous East to NErly LLJ (falling into the minus 4-5 sigma u-component of the wind at 925 and 850 mb). Increasing upper level diffluence ahead of the digging upper trough will support gradual enhancement of snowfall rates across all of Central PA today with snowfall rates within these quasi north/south bands of snow exceeding 1 inch per hour (possibly over 2 inches at times in heavy CSI bands across our far eastern CWA. A complicating feature that will enhance and extend significant impacts from this storm will be the increasingly strong NNE to NNW wind - that will gust over 30 mph tonight (and likely over 40 mph) on Monday. This will lead to significant/extensive blowing and drifting snow with localized near whiteout conditions possible. Previous disc... This deep center of low pressure at the surface and aloft will bring ample moisture and cold air into the region for winter storm conditions tonight into Monday. This system will bring heavy snowfall into portions of the Lower Susquehanna Valley. The WPC Winter Storm Outlook continues to tick higher, with much of the eastern half of the forecast area now seeing a 50 to 80 percent chance of seeing snowfall exceed warning criteria. We have issued a Winter Storm Warning for portions of the Lower Susquehanna Valley where we currently have the highest confidence in seeing 6 to 10 inches of snowfall. A prolonged period of upslope snow is also anticipated in the Laurel Highlands as flow behind the surface low becomes northwesterly. Most guidance continues to show a 48 hour period from early Sunday morning through early Tuesday morning where snow should fall, with 8 to 12 inches of snow expected along the ridges of Cambria and Somerset Counties. As a result, we have issued a Winter Storm Warning for those two counties as well. The enhanced wind gusts on the back side of this low pressure system could allow for gusts up to 40 mph in the Laurels, and brief periods of blizzard like conditions are not out of the question. KEY MESSAGE 2: A high degree of uncertainty remains with expected snowfall over the rest of northern PA. Significant uncertainty still remains regarding snowfall over the rest of North-Central, NW PA and the Middle Susq Valley considering the likelihood for a quasi-stationary nearly north/south band of heavy snow (lasting several hours or more) along the axis of an inverted llvl trough and leading edge of the lower/deeper DGZ that will be situated from the Scent Mtns to somewhere between KUNV/KSEG and KIPT later Sunday afternoon/Sunday night. A couple of things to keep in mind regarding this snowfall forecast: * As the low quickly deepens off the east coast, expect areas of enhanced low to mid level frontogenesis and UVVEL to develop in the western periphery of the system. Much of this banding will likely set up just east of the CWA, but could still develop across parts of our central and eastern zones. * Multiple models continue to show a snow band associated with an area of low level convergence within an inverted trough extending northwestward from the coastal low. While this type of band is more likely to set up somewhere in central PA, it will likely be narrow with a widely varying snowfall totals on either side of the band. KEY MESSAGE 3: Ice jam risk continues into the weekend, but no significant flooding expected. Cooler air moves in this evening as winds become westerly, allowing for a few snow showers over the north and west. The ice jam threat continues into the weekend as daytime highs in the 30s and 40s will support additional ice breakup. The threat for significant flooding is low as we are not anticipating any significant rainfall. Flooding would likely be localized and minor. && .AVIATION /12Z SUNDAY THROUGH THURSDAY/... Continued widespread deterioration of Cigs and Vsbys is expected as we head through this Sunday morning with snowfall expected to gradually increase in intensity based on all model guidance. The biggest uncertainty will actually remain at BFD, where recent HREF model guidance and obs have pointed twd lighter snowfall rates and higher end MVFR conditions through 15Z. Afterward, IFR conditions are being progged by the bulk of model guidance. Locally heavier snowfall rates are expected across southern terminals (JST/AOO/MDT/LNS) as we head through the TAF package with enhanced deep layer forcing, thus some potential for LIFR conditions between 20Z Sun and 00Z Mon with low-to- moderate (30-50%) confidence. The bulk of restrictions will be based on visibility based on recent GLAMP/NBM model guidance; however, will highlight that low ceilings (between 500-1000ft AGL) are also expected across much of central Pennsylvania as the low pressure area along the coast intensifies with the approach of an amplifying, increasingly neg tilt trough digging SE across the Glakes today/tonight. Winds will remain light throughout the first half of this current 12Z TAF package; however, a steady increase in wind/gusts from the NNE to NNW will occur tonight into Monday leading to frequent blowing and drifting of the snow and reduced vsbys. Outlook... Mon...Widespread IFR restrictions in snow. Gusty winds late Monday. Tue...MVFR-IFR restrictions possible in snow showers at BFD/JST, largely VFR elsewhere. Wed-Thu...Scattered rain and snow showers, restrictions possible. && .CTP WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory until 1 PM EST Monday for PAZ005-006- 010-011-037-041-046-051>053. Winter Storm Warning until 1 PM EST Monday for PAZ012-017>019- 025>028-034>036-042-045-049-050-056>059-063>066. Winter Storm Warning until 1 AM EST Tuesday for PAZ024-033. && $$ WHAT HAS CHANGED...Lambert/Bowen KEY MESSAGES...Lambert/Colbert/Bowen DISCUSSION...Lambert/Colbert/Bowen AVIATION...Lambert/Beaty |
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