Area Forecast Discussion
Issued by NWS Pittsburgh, PA
Issued by NWS Pittsburgh, PA
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812 FXUS61 KPBZ 252348 AFDPBZ Area Forecast Discussion National Weather Service Pittsburgh PA 648 PM EST Tue Nov 25 2025 .SYNOPSIS... Rain is favored through early Wednesday before a strong front crosses the region, ushering cooler but drier air through Wednesday night. Seasonably cool temperature is likely through the weekend, with potential for accumulating lake effect snow mainly for areas near and north of interstate 80. && .NEAR TERM /THROUGH WEDNESDAY/... KEY MESSAGES: - Rain continues into the overnight period but becomes more scattered in nature. - Warm advection plus overcast conditions will maintain a steady temperature state --------------------------------------------------------------- A decaying shortwave trough currently traversing the area will continue to foster widespread rain amidst modest warm advection through this evening. Area temperature could see momentary rises in rain breaks but will otherwise hold steady near the daily average. Exiting of the upper level shortwave tonight is expected to end the widespread, continuous rain occurrence. However, a deepening trough over the western Great Lakes fostering large scale ascent within the warm, moist southwest flow around the upper Ohio River Valley should maintain isolated to scattered rain showers into Wednesday morning. Due to excessive cloud cover and warm advection ahead of the next upper trough, temperature will see little nocturnal fluctuation as they hold steady in the upper 40s to lower 50s. && .SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/... KEY MESSAGES: - Rain tapers off morning/early afternoon - Gusty wind through Thursday - Falling temperatures Wednesday afternoon, colder Thursday - Snow showers Wednesday night through Thursday night N of I 70 - Lake enhanced snow along/north of I 80 Thursday and Thursday night ---------------------------------------------------------------- The mentioned upper trough will cross the Great Lakes on Wednesday with the associated cold front crossing late in the morning and into the afternoon. Temperatures will fall after FROPA with strong cold advection behind the front. A tightening pressure gradient, and steepening lapse rates in cold advection, will lead to gusty winds after FROPA, continuing into Thursday. Gusts from 30-40mph are likely for much of the area. Wind gusts could approach advisory levels (above 45mph) across the ridges, with NBM showing the highest probability of this occurrence across the higher terrain of eastern Tucker county WV. The current forecast uses a 50/50 blend of NBM and NBM90 for gusts, and eastern Tucker is still the only forecast zone at advisory levels. As the upper trough axis crosses the upper Ohio Valley region Wednesday night, rain will change over to snow with strong cold advection. Model soundings indicate a lack of saturation in the dendritic layer which should keep snow rates relatively low. The focus for snow will be largely north of PGH on Thanksgiving, as a vort max rotates through the main upper trough. There could also be some lake enhancement north of I-80 as the boundary layer flow begins to veer from SW to WSW, though the more favorable area for lake enhancement is just north of the forecast area. This is supported by latest analogs as well. As the boundary layer flow veers more to the NW Thursday night, another shortwave/vort max rotates through the main trough. Scattered snow showers are expected with this trough across much of the region, with more numerous lake enhanced snow showers near and north of I-80. A Winter Weather Advisory looks like it will be need to be issued for this time period. Will hold off for now with the hopes that the next suite of hi-res model runs hone in better on any banding. Current NBM probabilities for advisory level snow range from 30-75 percent (increasing from south to north) across the tier of counties north of I-80, and have continued to include this in the Hazardous Weather Outlook. Stay tuned for updates./ Much colder temperatures are expected by Wednesday night, continuing through Thursday night, with readings 10 to 15 degrees below average. && .LONG TERM /FRIDAY THROUGH TUESDAY/... KEY MESSAGES: - Snow showers gradually taper off from S-N Friday - Temperatures moderate over the weekend through early next week - Unsettled weather continues ------------------------------------------------------------------- With the trough axis east of the forecast area on Friday and surface high pressure building in from the west, boundary layer winds will become more southwesterly, and snow should gradually decrease through the day from S-N, though lingering lake enhancement could bring additional snow accumulations mainly north of I-80. Another shortwave trough is expected to rapidly track from the Midwest to the Upper Ohio Valley region late Saturday into Sunday, with rain and snow chances returning. Another trough in the amplified pattern aloft is expected to approach the region Monday, with mainly rain chances, though some snow is possible at the precip onset. Temperatures are expected to gradually moderate through the period. && .AVIATION /00Z WEDNESDAY THROUGH SUNDAY/... Broad ascent with warm and moist southerly flow overnight will continue to allow the chance of passing rain showers at most ports, though the predominant conditions will largely be precipitation free. With nocturnal trends and saturation, cigs will likely remain low, with LIFR forecast to continue overnight at FKL/DUJ, and IFR mostly elsewhere. Some slight downslope drying influence in southerly flow may temporarily keep MGW/LBE up to VFR/MVFR briefly before 06Z. Chances of IFR (and VLIFR at FKL/DUJ) drop below 50% in the 10Z to 13Z timeframe with diurnal trends and mixing and stronger south- southwesterly winds at daybreak. Given near-saturation and continued low instability, an occasional shower cannot be ruled out in the morning, but is generally unlikely until the frontal passage in the late morning and early afternoon. Southwest winds will continue to accelerate to 25kts to 35kts with mixing. This frontal passage will pack the potential for some gusty showers and perhaps the highest winds of the day with temperature drops of 15-20 degrees. Along with it, dry and cold advection will ensue, shifting winds west-southwest all the while. Tempos mentioned brief 40kt gust potential, matching about what the NBM max wind projects Wednesday. Whatever cig restrictions are left come the frontal passage will likely be replaced by a VFR stratocu deck. Shallow saturation in the mixed layer and cooling temperatures could also allow a brief period of light snow showers at the end of the TAF period. Outlook... Most terminals maintain VFR by Wednesday night with increasing subsidence and strong dry advection as upper troughing positions north of the region, though MVFR cigs could linger near FKL/DUJ. Lake effect snow will encroach FKL/DUJ Thursday morning depending on the angle of the 850mb wind, with a more likely push of lake bands coming late Thursday night into Friday. Height rises with surface high pressure should erode any restriction/snow by Friday night before the next low pressure system arrives Sunday morning. && .PBZ WATCHES/WARNINGS/ADVISORIES... PA...None. OH...None. WV...None. && $$ SYNOPSIS...Frazier NEAR TERM...Frazier SHORT TERM...88 LONG TERM...WM/88 AVIATION...Milcarek