Area Forecast Discussion
Issued by NWS State College, PA
Issued by NWS State College, PA
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164 FXUS61 KCTP 251054 AFDCTP Area Forecast Discussion National Weather Service State College PA 654 AM EDT Sat Jul 25 2026 .WHAT HAS CHANGED... No significant changes. && .KEY MESSAGES... 1) Pleasant/dry pattern with comfortably low daytime humidity will last through today before humidity gradually climbs on Sunday. 2) Turning more humid and unsettled early next week with the highest probability for showers and thunderstorms Monday afternoon and evening and again on Tuesday. && .DISCUSSION... KEY MESSAGE 1: Pleasant/dry pattern with comfortably low daytime humidity will last through today before humidity gradually climbs on Sunday. Broad, low-level streamline convergence with its N/S axis near the RT 219 corridor in Western PA was leading to an expanding area of Strato Cu clouds based mainly between 3-4.5 kft agl. Nothing other than a few sprinkles were noted across the SW PA low lands at this hour. As upper level diffluence slightly increases from the west today and a few embedded flat shortwaves move overhead during the late morning and afternoon, there will be isolated to scattered showers with MU CAPE only 500 J/KG or less. Will leave the isolated afternoon TSRA in for now to the west of RT 219, but would be surprised to see any in that part of our CWA based on the amount of morning cloud cover and TDs still only in the 50s to around 60F. KEY MESSAGE 2: Turning more humid and unsettled early next week with the highest probability for showers and thunderstorms Monday afternoon and evening and again on Tuesday. Minor modifications for this period that will be highlighted by a warm front moving across western PA Monday afternoon/evening, followed by a rather potent/digging mid/upper level shortwave, that will support a sub-995 mb sfc low over the Lower Glakes and Western NY Tuesday afternoon and evening. Latest model runs have trended several hours or so slower compared to runs 24 hours ago. The timing of the favorable lift associated with the thermally indirect, left front quad of the 80+ KT jet max moving across the Ohio Valley, WVA and southern PA Tuesday afternoon and evening will help to enhance a low level lee trough and convection along it. Scattered strong to severe TSRA are likely Tue afternoon and evening over at least the eastern half of the CWA with a second line of TSRA likely along the cold front across NW PA Tuesday afternoon. && .AVIATION /12Z SATURDAY THROUGH WEDNESDAY/... Borderline MVFR-to-VFR conditions AT JST/AOO will likely continue for the next couple of hours before VFR conditions are more likely to prevail. Some scattered shower development is expected this morning in close vicinity to JST/AOO; however, confidence remains low in any showers impacting the airfield through 18Z Saturday. Chances gradually expand northward and eastward late this afternoon and evening, with increased chances at BFD/JST in the 18Z-06Z timeframe for some showers but given the scattered nature, not confident enough to include mentions and/or restrictions at this time. If showers do form and go over BFD/JST in this timeframe, MVFR ceilings appear to be the most likely solution, generally between 2,000 and 3,000ft AGL for a one-to-two hour period. Towards the end of the 12Z TAF package, higher confidence in some restrictions at BFD/JST with lesser chance at AOO/UNV based on recent HREF probabilities. Given this trend, have highlighted MVFR-to-IFR restrictions which is slightly more optimistic than GLAMP model guidance based on the 25th percentile member of the HREF ensemble. Lower solutions can play out; however, especially if BFD/JST/AOO/UNV receive any rainfall today which would promote lower restrictions based on visibilities and ceilings between 08-12Z Sunday. Outlook... Sun...VFR favored with a few showers/storms possible, mainly over western-central PA. Mon-Wed...Restrictions likely in showers/storms. && .CLIMATE... Cooler than average temperatures across the region led to multiple record low temperatures being broken for July 23rd and July 24th across central Pennsylvania. On July 23rd: * Altoona set a record low temperature of 47 degrees, breaking the previous record of 50 degrees set back in 1981. * Bradford tied a record low temperature of 38 degrees which was previously set in 1981. * Johnstown tied a record low temperature of 49 degrees which was previously set in 1983. On July 24th: * Altoona set a record low temperature of 47 degrees, breaking the previous record of 50 degrees set back in 1957. * Bradford set a record low temperature of 41 degrees, breaking the previous record of 44 degrees set back in 1993. && .CTP WATCHES/WARNINGS/ADVISORIES... None. && $$ WHAT HAS CHANGED...Lambert/Steinbugl KEY MESSAGES...Lambert/Steinbugl DISCUSSION...Lambert/Steinbugl/Martin AVIATION...Beaty CLIMATE...Beaty