Area Forecast Discussion
Issued by NWS Pittsburgh, PA
Issued by NWS Pittsburgh, PA
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956 FXUS61 KPBZ 271635 AFDPBZ Area Forecast Discussion National Weather Service Pittsburgh PA 1235 PM EDT Sun Sep 27 2026 .WHAT HAS CHANGED... Rain chances east of Pittsburgh this afternoon and evening were raised slightly. Higher confidence in above-normal temperatures by Thursday, with increased chances of highs reaching 80. No other notable changes. && .KEY MESSAGES... 1) Light rain to the east of Pittsburgh on the outer fringes of the nor`easter 2) A mostly dry stretch of weather from Monday through Thursday with warming temperatures, before a late week front returns precipitation && .DISCUSSION... KEY MESSAGE 1... The nor`easter spinning just off of the coast of New Jersey is still expected to spread more cloud cover into the Upper Ohio Valley during the afternoon and evening hours. Wraparound precipitation has been making westward progress across PA and is still expected to reach as far west as Forest, Clarion, Armstrong, and Westmoreland Counties during the early evening, with perhaps a few sprinkles further west. Abundant amounts of dry air below 500mb, as noted on the 12Z PBZ sounding, will limit rainfall extent and intensity, such that generally 0.10" or less is expected. A decent pressure gradient and good mixing should keep northerly 20 to 30 MPH wind gusts going until sunset stabilizes the boundary layer somewhat. Rain chances decrease later tonight as the nor`easter starts to waddle northeastward towards Cape Cod, but a few upslope showers may linger along the ridges southeast of Pittsburgh as surface wind backs slightly towards northwest. Clouds should linger into Monday night. KEY MESSAGE 2... As the coastal trough associated with the nor`easter pulls offshore, 500mb ridging will be able to build across the Upper Ohio Valley by 12Z Wednesday. Dry weather will result into Thursday, with that latter day representing the peak of a warming trend as southwest flow amps up behind a Carolina surface high. NBM probabilities for 80F or greater high temperatures that day have risen to between 50 and 80 percent for most non-ridge locations south of I-80. That said, dewpoints topping out in the low 60s will keep heat risk concerns relatively muted. Currently, probabilities for moderate or higher heat risk levels are 10 percent or less. There are differences in opinion in the longer-range models regarding the strength and timing of the next shortwave trough crossing the Canadian prairies and potentially the Great Lakes later in the week. Still, at least scattered shower activity becomes more likely Thursday night/Friday in the moistening warm sector, with rain chances lingering into the weekend. Severe weather potential looks muted by meager instability, and probabilities for significant rain are low (40 percent less or chance for >0.50 inch in any 24-hour period). Given the increased clouds and rain chances, temperatures should tumble back to, or perhaps a bit below, climatology by Saturday. && .AVIATION /13Z SUNDAY THROUGH THURSDAY/... Light rainfall remains possible across our eastern ports this evening on western periphery of coastal storm with clouds and precipitation backing in from east of the mountains. Gradual moistening of the column will result in VFR ceilings gradually dropping to MVFR in the evening. Ceilings will continue to drop becoming IFR at FKL and DUJ by tonight. Tomorrow morning, IFR ceilings are likely as far west as KPIT. There is greater than a 60% probability of IFR ceilings sticking around through Monday morning for most. Outlook... Restrictions will gradually improve during the day on Monday. Due to the chance for radiation fog, there is chance for them to return Tuesday morning, otherwise conditions will remain VFR until the next disturbance moves into the area mid to late week. && .PBZ WATCHES/WARNINGS/ADVISORIES... PA...None. OH...None. WV...None. && $$ DISCUSSION...CL AVIATION...Craven/Lupo