Area Forecast Discussion
Issued by NWS Pittsburgh, PA
Issued by NWS Pittsburgh, PA
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616 FXUS61 KPBZ 152206 AFDPBZ Area Forecast Discussion National Weather Service Pittsburgh PA 506 PM EST Sat Nov 15 2025 .SYNOPSIS... Increasing moisture and warmth will help fuel showers and a few gusty thunderstorms this evening, ahead of a crossing cold front. Blustery and cooler weather is on tap for Sunday with northwest-flow showers. Lake-effect snow is expected north of I-80 Sunday night into Monday. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... KEY MESSAGES: - Showers and spotty thunderstorms with strong wind gusts this evening - Wind gusts to 50 mph over east Tucker County WV ridges --------------------------------------------------------------- Cold front on the nose of a strengthening 500mb jet will provide support for showers and potentially a few thunderstorms this evening. We continue to monitor the potential for thunder and any severe weather risk, with the timing mainly between the hours of 6 PM and 11 PM. When it comes to severe risk, there remains plentiful deep- layer shear, with 45-55 knots in the 0-6km layer. Warm advection is helping to keep temperatures elevated, at least early this eve, which could help even with the cloud cover. But lapse rates at the surface and aloft are still not entirely favorable for the transfer of momentum as noted in ACARS soundings and in the hi res model guidance. Surface- based CAPE also remains marginal per the latest mesoanalysis, at around 200-300j/kg. Still we cannot rule out a couple occurrences of strong to damaging wind gusts at the surface, and even if the full potential is not maximized, there will be a period of 35-45mph gusts across the region, as already noted upstream. QPF through tonight will not be problematic; NBM 25-75th percentile values are generally between 0.10 and 0.50 inch for most of the forecast area. Shower coverage drops off quickly post-FROPA, although areas along the terrain may see some scattered activity linger into the overnight hours. Cold advection will bring overnight lows into the 30s north of Pittsburgh and the 40s from the city south. Gusty wind to 30 MPH will continue even away from showers/storms through tonight. With the shift to northwest flow overnight, strong pressure rises/cold advection will lead to 45-55 MPH gusts over the eastern Tucker Ridges, mainly above 3,500 feet. Continued the ongoing Wind Advisory that is in effect through Monday morning. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY/... KEY MESSAGES: - Blustery and colder Sunday, with showers continuing north of Pittsburgh - Wind gusts to 55 mph over east Tucker County WV ridges - Probable lake effect snow band late Sunday into Monday north of I-80 ---------------------------------------------------------------- Gusty wind continues through this period thanks to a tight surface pressure gradient and ongoing cold advection keeping low-level lapse rates steep. Gusts in the lowlands of 30 to 35 mph, higher in the ridges, and continuing to peak over 45 MPH in eastern Tucker County, won`t diminish until later Monday morning. Scattered northwest-flow showers are forecast mainly north of US-422 and especially north of I-80 on Sunday. A mix with, and then a change to snow is expected as 850mb temperatures fall farther below zero C, eventually reaching the -7C to -9C range by Monday. Any showers closer to Pittsburgh are likely to remain more rain with temperatures peaking in the lower 40s. Little accumulation of snow is forecast during the Sunday daylight hours. Most guidance continues to advertise a persistent lake-effect band developing that very well may have a three lake connection (Superior/Huron/Erie). Development would occur Sunday night, with the band persisting into Monday afternoon. The exact placement of the band may waver a bit, but Forest seems to be the most likely county of impact, with portions of Venango, Clarion, and Jefferson also possibilities. Currently, we expect at least 2-5" in areas that get under the band for a length of time, and some model solutions suggest 6"+ is still a possible outcome in the heaviest cases. Will allow for one more HREF run to fully encompass the event before considering the issuance of any lake effect snow headlines. Any accumulation south of I-80 will be limited to a coating at best, with little more than a flurry or two south of the PA Turnpike. In fact, cloud coverage of less than 50 percent is project for most of the area south of I-70. Even the Laurels and West Virginia ridges are not projected to see any snow of note as moisture remains too shallow overall. Subfreezing temperatures Sunday night will be followed by a chilly Monday, with highs in the 35 to 45 degree range. && .LONG TERM /MONDAY NIGHT THROUGH SATURDAY/... KEY MESSAGES: - Lake-effect snow ends Monday night - New disturbance returns rain/snow to the region Tuesday - Above average temperatures mid to late week ------------------------------------------------------------------- Any lingering lake-effect snow showers north of Pittsburgh Monday evening should taper off after sunset as boundary-layer winds weaken and prevail from the west, cutting off the Great Lakes fetch. Early Tuesday morning lows are expected to fall into the low to mid-20s under radiational cooling and continued cold advection--roughly 10 degrees below climatological averages. Cloud cover and precipitation chances will increase Tuesday as a new disturbance moves out of the Great Plains into the Ohio River Valley. Given residual dry air in the low and mid-levels, wet-bulb effects may allow some locations to start with snow before transitioning to rain as warm advection strengthens. Confidence remains low due to uncertainty in the low`s track and dry slot placement. If snow does occur, it will likely be a heavy, wet type with snow rations around 6:1 to 8:1. The probability of precipitation beginning as snow is estimated at 10-20%. More than half of the long-range model guidance favors a developing ridge over the Great Lakes from Wednesday through Friday, supporting above-average temperatures during this period. There is no strong indication of widespread rainfall between Wednesday through Thursday night, and the probability of any precipitation remains low, generally around 30-35%. Several model runs suggest a more substantial disturbance developing over Oklahoma and Texas and then moving into the region on Friday. Confidence in rainfall amounts remains low; model analysis shows only about a 25% chance of 24-hour precipitation amounts reaching or exceeding a half inch. && .AVIATION /21Z SATURDAY THROUGH THURSDAY/... Moisture has increased behind a morning warm frontal passage. MVFR ceilings are already present at most terminals, and these ceiling should persist into this evening. Southwest wind will continue to gust into the 20 to 25 knot range as well. A few scattered showers (covered by PROB30 groups) can be expected into the evening, ahead of a crossing cold front.T The front will cross during the late evening hours, bringing a concentrated area of showers and a few thunderstorms. Have used two-hour TEMPO groups to try to time the most likely hours of occurrence at the terminals. Have used lower-end MVFR ceiling and visibility for now. Cannot rule out a brief period of heavy rain creating IFR visibility, as well as a wind gust or two into the 30 to 40 knot range in the heavier showers/storms. Rain coverage will quickly decrease overnight behind the front, although some northwest-flow showers may begin to show up at FKL/DUJ after 12Z Sunday. Wind will shift to northwest behind the front, and continue to gust to 20 to 25 knots overnight. Wind gusts may increase to 30 knots or so once deeper mixing becomes established later Sunday morning. Outlook... Lake-enhanced precipitation is expected behind the front on Sunday with the typical scattered nature. MVFR cigs are likely to persis at FKL/DUJ into Sunday afternoon. Another crossing disturbance may bring rain and snow to the region on Tuesday. && .PBZ WATCHES/WARNINGS/ADVISORIES... PA...None. OH...None. WV...Wind Advisory until 10 AM EST Monday for WVZ514. && $$ SYNOPSIS...CL NEAR TERM...34/CL SHORT TERM...CL LONG TERM...Hefferan AVIATION...CL