Area Forecast Discussion
Issued by NWS Pittsburgh, PA
Issued by NWS Pittsburgh, PA
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381 FXUS61 KPBZ 300550 AFDPBZ Area Forecast Discussion National Weather Service Pittsburgh PA 1250 AM EST Sun Nov 30 2025 .SYNOPSIS... Light snow overspreads the area tonight and transitions to rain after sunrise Sunday. Minimal accumulation is expected for most, though totals up to 4 inches are possible along the I-80 corridor. More widespread accumulating snow is expected with another system on Tuesday. && .NEAR TERM /THROUGH TODAY/... KEY MESSAGES: - Snow transitions to rain Sunday - 1-3 inches north of I-80 - Glaze of ice accumulation possible in ridges of SW PA and northern WV, where a Winter Weather Advisory is now in effect from 3am until Noon Sunday. --------------------------------------------------------------- As of midnight, still taking awhile to fully moisten up the lower levels, though snow is now reaching the ground along the I-80 corridor. Area dewpoint depressions average 20-25 degrees. This will limit snowfall accumulations even more than originally anticipated, keeping totals north of I-80 in the 1-2 inch range (up to 3 in isolated locations). Heaviest snowfall for that area appears to be in the 8-10am timeframe before transition to rain. Elsewhere, a light dusting to a half inch is expected, mainly north of PGH, before snow turns to rain later this morning. Peaks of the ridges are still on track for a light glaze of ice this morning. An Advisory remains in effect from 3 AM through Noon. Previous Discussion... 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. There are two primary areas of concern with this system: 1) accumulating snow along/north of I-80, and 2) potential for freezing rain in the ridges of southwest PA and northern WV. Regarding concern number 1, at this time guidance continues to suggest the most likely snowfall amounts range from 1-3 inches along and north of the I-80 corridor with lower totals farther south. Ensemble probabilities for exceeding 3 inches continue to decrease, with the NBM now showing a less than 10% chance. Additionally, the NBM now only shows a 20-30 percent chance of exceeding 2 inches. That said, hi-res guidance continues to suggest the possibility for some convective snow showers Sunday morning before transitioning to rain or ending completely. Therefore, a few localized amounts up to 4 inches can`t be entirely ruled out, but given such low probabilities and the isolated nature of these higher totals (should they occur), the decision now is to continue holding off on issuing any winter headlines north of I-80. Regarding concern number 2 from above, investigation into model soundings in the ridges of southwest PA and northern WV suggest that supercooled water content in clouds and near- surface thermal profiles may be supportive of freezing rain mixing in with rain/snow, primarily during overnight and early morning hours Sunday. Therefore, a glaze of ice accumulation will be possible and a Winter Weather Advisory has been issued for these areas from 3am until Noon Sunday. Widespread precipitation should end through Sunday afternoon as the cold front crosses. Lingering rain and snow showers, favored north of Pittsburgh, will transition back to all snow as temps cool behind the front towards sunset Sunday evening. Any additional snowfall amounts would be light. && .SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/... KEY MESSAGES: - Snow north of Pittsburgh trails off Sunday night - Dry and cold Monday - POPs rise again by Monday night ---------------------------------------------------------------- Snow showers linger north of Pittsburgh in NW flow early Sunday night. An additional 0.5-1" will be possible along the I-80 corridor overnight. POPs trail off overnight as dry advection takes over and short lived high pressure noses in across the Ohio River Valley. High pressure continues dry conditions through the day Monday but few breaks in the cloud cover are favored behind our exiting system and ahead of our next system. High temps remain well below average for this time of year, peaking in the low to mid 30s. Another shortwave builds through the flow and moves eastward towards the Great Lakes by Monday afternoon. At the SFC, this drags a low up from the Gulf Coast and through the Southeast, positioning us on the far northern edge. As such pops begin to increase quickly overnight Monday night with snow favored to begin before sunrise. && .LONG TERM /TUESDAY THROUGH SATURDAY/... KEY MESSAGES: - Active pattern continues - Snow and rain return Tuesday, then again Thursday/Friday - Below normal temperatures through the period ------------------------------------------------------------------- The exact storm track through the southeast and off the Atlantic Coast will determine the exact progression of precipitation types for Tuesday. At this time models have shifted southward over the last 24 hours putting more of the region in the cold air and raising chances for accumulating snowfall. Stout warm advection up the ridges hints at the chance to see some freezing rain in our WV ridges overnight Monday. Ice accumulations of a glaze up to a few hundredths could be possible by Tuesday morning. As temperatures rise during the day areas mainly south of Pittsburgh can see a changeover to a rain/snow mix, with areas north likely to stay all snow. Snowfall totals are likely highest north of Pittsburgh and especially along the I-80 corridor, where probabilities for advisory level snow are the highest and probabilities for warning level snow peak between 10-20%. Uncertainty increases closer to Pittsburgh as the exact location of the transition zone will largely factor into how much snow areas see. The noted southern shift in modeling over the last 24 hours would favor more snow in the metro and currently paints the relative minimum of snow across the Mon Valley. If this trend continues, in a colder and snowier solution, we could end up needing a Winter Weather Advisory for much of the forecast area outside of the Mon Valley. However, we will have to wait as fluctuations in exact track will shift the transition zone and totals over coming forecast cycles. POPs begin to trail off by Tuesday night as high pressure enters the Ohio Valley. This returns dry conditions for Wednesday before snow chances pick up again late week with another passing system. Temperatures are likely to remain below average through the period favoring daytime highs in the low to mid 30s. && .AVIATION /06Z SUNDAY THROUGH THURSDAY/... With dry low levels, precipitation is still having a hard time reaching the ground across the Upper Ohio Valley. It will take a few more hours for most terminals to start to see light precipitation, and at present, most south of I-80 will likely see little meaningful visibility restriction through the morning hours. FKL/DUJ have the best chance of seeing MVFR/IFR visibility at times from snow through 14Z or so. Any precipitation will mix with and eventually change to rain, with the change moving from south to north between 08Z and 15Z. Ceilings, however, will show a downward trend as the column moistens from the top down. Initial VFR ceilings should drop into the MVFR range late tonight, and generally stay at that level through the remainder of the TAF period. Southeast wind will veer towards the south overnight and become gusty, with peaks between 15 and 25 knots. Increased mixing during the daylight hours will lead to gusts in the 20 to 30 knot range as veering towards the southwest continues. Any precipitation largely ends by the early afternoon, although MVFR ceilings will linger. Another round of snow showers may show up near FKL towards midnight Sunday night. Outlook... VFR returns to the area on Monday as high pressure moves across the area. This is quickly followed by yet another low pressure system, which moves into the area and brings another round of wintry precipitation and associated restrictions on Tuesday. && .PBZ WATCHES/WARNINGS/ADVISORIES... PA...Winter Weather Advisory until noon EST today for PAZ074-076. OH...None. WV...Winter Weather Advisory until noon EST today for WVZ512-514. && $$ SYNOPSIS...MLB/AK NEAR TERM...Cermak/Rackley/MLB SHORT TERM...AK LONG TERM...AK AVIATION...CL