Area Forecast Discussion
Issued by NWS State College, PA
Issued by NWS State College, PA
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859 FXUS61 KCTP 032341 AFDCTP Area Forecast Discussion National Weather Service State College PA 741 PM EDT Thu Sep 3 2026 .WHAT HAS CHANGED... * Convection timing narrowed. && .KEY MESSAGES... 1) Showers and thunderstorms into tonight can hold heavy rain and damaging winds. A small chance of tornadoes and hail also exists. Additional storms possible Friday. 2) Dry weather returns on Saturday and lasts through the weekend. && .DISCUSSION... KEY MESSAGE 1: Showers and thunderstorms into tonight can hold heavy rain and damaging winds. A small chance of tornadoes and hail also exists. Additional storms possible Friday. Weak wave crossing LE has been touching off a few TSRA farther to the west. However, the shallow cu and higher stability overhead indicate that it`s influence to cause new storms locally will be low. However, the high humidity and slight convergence over nrn tier counties will help a couple of tall cells to build up before 22Z. The main show is shortly afterward, though. Much stronger short wave trough is moving through lower MI and should drive a complex of storms through most/all of the CWA this evening. Arrival in the NW should be around 22Z and exit to the east of the CWA will be in the 02-03Z range. The strong dynamics and initial curve to the hodographs in the NW may generate a few supercells. Then, the vertical wind profile becomes more W-E/linear. That should result in a more clustered or linear mode, ripe for a bow echo. 70-75F dewpoints and PWAT near 2" this evening (highest S) will make heavy rain a possibility, too. The risk for flooding still exists, especially because of the very wet ground due to the past 36-48hr rainfall. However, the faster the storm motions are, the lower a risk it could be. The problem this evening is as it has been - multiple/repeated storm cores moving over the same spots. Will keep on with the FF Watch thru midnight. Timing should encompass all of the threat. Heat index numbers haven`t quite built to the point expected yet, likely due to the delayed onset of sunshine. But, we`ll keep the advisory in place until 8 PM as the temps could jump another 5-6F before it starts to cool off over the S now that they have nearly full sunshine. The cool air that the storms this evening generate will help to nudge a cold front off to our S tonight. But, not very far south of PA. It won`t take much forcing to fire up SCT-NMRS storms on Friday. PoPs may be a little high for Fri-Fri night, but we`ll follow the recent trend toward a wetter forecast. These will stay closer to the MD border, but isold storms will form as far as the NY border. SPC outlook has been consitently worse (SLGT) for the Laurels on Fri. ------------------------------------------------------- KEY MESSAGE 2: Dry weather returns on Saturday and lasts through the weekend. Upper low over New England will close even more and drop a little to the south as cooler air slides into NY/PA. The cold front finally gets far enough to our south to keep all the SHRA/TSRA off to our south on Sat. Other than some morning valley fog, the wx will be really nice for the holiday weekend. Highs mainly in the 70s and lows 45-55F both Sat night and Sun night. Upper ridge inches to the east from the central states into mid-week. Quiet weather stretch will be welcomed by many. Next chc precip isn`t until Wed-Thurs. && .AVIATION /00Z FRIDAY THROUGH TUESDAY/... As of early evening, isolated showers and storms so far. Line of severe storms across the far southwest likely to still be brushing the JST area around 00Z, so have strong wind gust in that TAF. For other areas, not as strong with wind gust in the tempo group with storms this evening. Overnight and early Friday morning, expect CIGS to lower. Conditions will slowly improve later Friday morning into the afternoon hours, as slightly drier air trys to edge southward. Still a chance of a shower or storm, mainly across the south. Left out of the TAFS for now, as much of the activity could remain just south of the TAF sites. Outlook... Sat-Tue...VFR favored; morning fog possible. && .CTP WATCHES/WARNINGS/ADVISORIES... Flood Watch until midnight EDT tonight for PAZ004>006-010>012- 017>019-024>028-033>037-041-042-045-046-049>053-056>059- 063>066. Heat Advisory until 8 PM EDT this evening for PAZ026>028-035- 036-056-057-059-063>066. && $$ WHAT HAS CHANGED...Dangelo KEY MESSAGES...Dangelo DISCUSSION...Dangelo AVIATION...Dangelo/Martin