Area Forecast Discussion
Issued by NWS Pittsburgh, PA
Issued by NWS Pittsburgh, PA
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862 FXUS61 KPBZ 280014 AFDPBZ Area Forecast Discussion National Weather Service Pittsburgh PA 814 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... Wraparound rain from the Nor`easter spinning off the New Jersey coastline is sliding down the west side of the ridges at this time. POPs have been raised slightly a little further west to catch this. Early looks at the 00z Pittsburgh RAOB show less dry air at the surface than previously expected, this is showing up in DUJ obs, where reports are already up to 0.12 inches of rain. Light rain trails off after this band passes and POPs drop appreciably overnight. Widespread boundary layer gusts between 20-30 mph are beginning to wind down as the boundary layer decouples. 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 /00Z MONDAY THROUGH FRIDAY/... A general deterioration in cig height is anticipated overnight as precipitation and clouds on the periphery of the coastal low continue to move into the region. The latest guidance slows the timing of the MVFR/IFR ceilings just slightly, so the biggest adjustment to the forecast reflects those changes. At this time, only ZZV looks to generally stay away from a prolonged period of restrictions, though with minimal cloud cover could have a brief period of fog toward daybreak per the HREF. Fog is also possible at the sites that receive light precipitation (KDUJ and KLBE with higher confidence; KMGW and KAGC with lower confidence). Gradual improvement in ceilings is anticipated on Monday though there remains a 30%-50% probability of IFR ceilings sticking around through midday at sites north and east of Pittsburgh. Further west it may take much of the day to return to VFR. Outlook... VFR is generally anticipated to prevail outside of morning fog potential until the next disturbance moves into the area mid to late week. && .PBZ WATCHES/WARNINGS/ADVISORIES... PA...None. OH...None. WV...None. && $$ DISCUSSION...CL/AK AVIATION...34