Area Forecast Discussion
Issued by NWS Pittsburgh, PA
Issued by NWS Pittsburgh, PA
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640 FXUS61 KPBZ 290733 AFDPBZ Area Forecast Discussion National Weather Service Pittsburgh PA 233 AM EST Sat Nov 29 2025 .SYNOPSIS... After dry weather today, snow is expected tonight, transitioning to rain after sunrise Sunday. Brief and light accumulations are expected for most, though 3 to 4 inches are possible along the I-80 corridor. More widespread snow is is expected with another system on Tuesday. && .NEAR TERM /THROUGH TODAY/... KEY MESSAGES: - Chilly temperatures and briefly dry conditions --------------------------------------------------------------- Snow and most flurries have ended this morning. Despite cloud cover, lingering cold advection will help drop area lows into the upper teen and lower 20s. Skies will partially scatter for the first part of today as we experience briefly dry conditions. Afternoon temperatures should end up a couple degrees warmer than Friday, but still 10+ degrees below average. && .SHORT TERM /TONIGHT THROUGH MONDAY/... KEY MESSAGES: - Snow returns tonight, transitioning to rain Sunday morning/afternoon - 3-4 inches possible north of I-80 - Dry on Monday ---------------------------------------------------------------- Surface high pressure will quickly exit east today as low pressure develops across the Upper MS Valley, crossing into the Great Lakes tonight. Precipitation chances will initially overspread the area from the west late this evening and overnight -- initially as snow for most -- before transitioning to rain and a rain/snow mix with strong warm advection Sunday morning and afternoon. High temperatures may push into the lower 40s for much of the region before cooling once again behind a cold front. The overall forecast hasn`t changed much over the last several cycles, but there was a notable downward trend in snowfall with the 01z NBM run. Snowfall totals will be highest across NW Pennsylvania, where profiles remain cold enough to support snow or a rain/snow mix through most of the morning if not early afternoon. In some locations (e.g. parts of Mercer and Venango counties), this will be falling on top of several inches of snowpack. At this time, generally 2-4" is expected across Mercer, Venango, and Forest counties, with northern portions of Butler, Clarion, and Jefferson exceeding 2". Less than 2" is expected elsewhere north of Pittsburgh, with an inch to a dusting farther south. Outside of the I-80 corridor, impacts from snowfall will be negligible as snow quickly transitions to rain Sunday morning. Slick conditions could persist into the afternoon north of I-80 as rain falls on snow and cold ground with air temperatures still in the mid/upper 30s. Given borderline Advisory criteria (40-45% for northern Mercer/Venango) and the downward trend, have held off of issuing a Winter Weather Advisory for now. Widespread precipitation should end through the afternoon as the cold front crosses. Lingering rain and snow showers, favored north of Pittsburgh will transition back to all snow as temperatures cool behind the front and after sunset Sunday night. An additional 0.5-1" is possible along the I-80 corridor overnight. Dry weather returns (briefly, again...) on Monday as high pressure builds across the Great Lakes. Clouds will likely persist through the day, and temperatures remain well below- average with highs in the 30s and lows in the 20s. && .LONG TERM /MONDAY NIGHT THROUGH FRIDAY/... KEY MESSAGES: - Active pattern continues - Snow and rain return Tuesday, then again Thursday/Friday - Below normal temperatures through the period ------------------------------------------------------------------- The active pattern continues midweek with yet another chance for snow as a shortwave crosses the Great Lakes and a Southeast US surface low tracks up the coast. Precipitation chances return later Monday night and Tuesday, exiting by Tuesday night. Uncertainty remains with regards to QPF and snow totals, but confidence in the colder solution is increasing. Snow is likely to begin Monday night, with areas south of Pittsburgh transitioning to a rain/snow mix later Tuesday morning. Snowfall totals will likely be highest north of Pittsburgh along the I-80 corridor, where probabilities for 3+ inches is around 40-50%. Uncertainty in totals increases near the Pittsburgh metro and areas farther south, as precip type transition timing will come into play. Dry weather should return Wednesday with weak ridging and building sfc high pressure, before minor snow chances return Thursday and Friday with the next frontal system. Temperatures will be below average through the period. && .AVIATION /06Z SATURDAY THROUGH WEDNESDAY/... Broad cyclonic flow around a mid-level closed low centered just north of Maine has continued to provide favorable northwest flow with cold air over the lakes for lake effect snow showers. These have been more cellular in nature this evening bringing temporary restrictions to IFR vis within the heavier showers. Conditions outside of snow showers have been VFR with a mid- level BKN to OVC cloud deck. Headed into tonight, expect that increasing subsidence from approaching high pressure to our southwest will cut off the depth of the moisture and dissipate snow showers south of I-80. VFR conditions will prevail overnight at all sites, save FKL/DUJ, with the mid-level cloud deck slowly breaking up and wind diminishing to around 5-10 knots overnight. For FKL/DUJ, expect that BKN to OVC ceilings will hover right around 3kft with some lake effect snow showers able to hang on through midnight or so and bringing temporary MVFR/IFR restrictions. Improvement back to low-end VFR is favored after that, but northwest flow will still keep the highest cloud coverage at those two sites. VFR continues for most of Saturday as wind backs from the west to ultimately southeast throughout the day but generally remains light around 5 knots. Increasing cloud coverage will overspread from the west in the afternoon ahead of approaching low pressure. Outlook... The next low pressure system arrives early Saturday night, creating widespread precipitation chances with increasing probability for on MVFR to IFR restrictions Saturday night through Sunday morning. Thermal profiles suggest initial precipitation may fall as snow and have some potential for accumulation (favoring ZZV/BVI/FKL/DUJ) before warm advection aides in a changeover to rain. && .PBZ WATCHES/WARNINGS/ADVISORIES... PA...None. OH...None. WV...None. && $$ SYNOPSIS...Rackley NEAR TERM...Rackley SHORT TERM...Rackley LONG TERM...Rackley/88 AVIATION...CL