Area Forecast Discussion
Issued by NWS Pittsburgh, PA
Issued by NWS Pittsburgh, PA
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765 FXUS61 KPBZ 281659 AFDPBZ Area Forecast Discussion National Weather Service Pittsburgh PA 1259 PM EDT Mon Sep 28 2026 .WHAT HAS CHANGED... Light rain shower/sprinkles chances increased slightly this afternoon. No other major changes. && .KEY MESSAGES... 1) A mostly dry stretch of weather through Thursday with warming temperatures, before a late week front returns precipitation chances && .DISCUSSION... KEY MESSAGE 1... Wraparound moisture/clouds from the lingering nor`easter will continue to spin across our region today in northerly flow. A few sprinkles or light rain showers remain possible near and north of Pittsburgh this afternoon, especially in upslope-prone regions, but limited lift and instability will keep any precipitation totals very light. Temperatures should continue to run a few degrees below climatology, save for areas near ZZV that are receiving more sunshine and will be a bit closer to normal. The upper low associated with the coastal system will drift northward across southern New England tonight towards the Gulf of Maine, finally devolving into an open wave over the Canadian Maritimes tomorrow night. Clouds will begin to break tonight as this process begins. Any locations that manages to clear may quickly fog in given the nearly saturated boundary layer and a very weak surface pressure gradient. The cloud decrease continues Tuesday/Tuesday night as mid-level ridging crosses the Upper Ohio Valley. Surface high pressure also arrives and remains in control into Thursday. The increased sunshine and rising heights will push temperatures back above normal while maintaining dry conditions. NBM probabilities for 80F or greater high temperatures that day remain in the 55 to 80 percent range for most non-ridge locations south of I-80. Dewpoints in the lower 60s that day, however, point to less heat stress - probabilities for Moderate or higher HeatRisk values remain under 20 percent for the most part. 500mb flow flattens after Thursday as a shortwave trough crosses eastern Canada. Strength and timing issues remain with this disturbance, although most of the uncertainty lies to our north. That said, at least scattered shower activity becomes more likely Thursday night/Friday in the moistening warm sector with an approaching front, with rain chances lingering into the weekend. Severe weather potential looks muted by meager instability, and probabilities for problematic rainfall totals remain quite low. && .AVIATION /14Z MONDAY THROUGH FRIDAY/... Except for ZZV, which is enjoying VFR conditions, MVFR ceilings will linger at most TAF sites into the evening. Some patchy light rain and drizzle will continue over western PA terminals as well, potentially dropping ceilings to IFR levels at times. Some improvement to upper-end MVFR heights, or even VFR, is possible during the evening. Overnight, clouds should begin to break with the nor`easter pulling further offshore. Given the saturated boundary layer and light wind, stratus and radiation fog formation is forecast towards 06Z at sites that manage to clear briefly. Do expect IFR to LIFR in fog for most locations Tuesday morning. After fog lifts Tuesday mid morning, ceilings should rise to VFR levels by the afternoon. There is potential for a repeat of radiation fog late Tuesday night and early Wednesday. Outlook... VFR is expected Wednesday and Thursday. Restrictions are possible Friday with showers returning. && .PBZ WATCHES/WARNINGS/ADVISORIES... PA...None. OH...None. WV...None. && $$ DISCUSSION...CL AVIATION...CL