Area Forecast Discussion
Issued by NWS Pittsburgh, PA
Issued by NWS Pittsburgh, PA
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897 FXUS61 KPBZ 082349 AFDPBZ Area Forecast Discussion National Weather Service Pittsburgh PA 649 PM EST Sat Nov 8 2025 .SYNOPSIS... There is the potential for fog early Sunday south of Pittsburgh. Rain chances increase after dawn with a passing low pressure disturbance. Rain showers will transition to snow showers after dark Sunday with advancing cold air. Snow accumulations could impact the higher terrain and areas north of I-80 Monday into Tuesday. && .NEAR TERM /THROUGH SUNDAY/... KEY MESSAGES: - Potential for fog early Sunday south of Pittsburgh - Rain chances increase after dawn Sunday - Rain is expected to change to snow between 7pm to 11pm Sunday --------------------------------------------------------------- Quiet and dry conditions are anticipated from late this evening until 2am, under the influence of high pressure. There`s a possibility of clearing skies south of Pittsburgh, which could lead to fog formation. A low-pressure system currently over Illinois will move into our area after sunrise on Sunday. Due to warm temperatures as winds remain from the east/southeast and/or variable, the precipitation will begin as rain. Expect light rainfall, ranging from a trace a tenth of an inch to a quarter of inch through 7pm. From 7pm to 11pm, rain showers are expected to briefly change to a wintry mix before turning into snow. As the low-pressure system moves northeast into New York, north/northwest winds will likely bring lake-effect snow due to warm lake temperatures. Higher elevations in the Laurel Highlands and West Virginia might see light snow accumulation before midnight as well due to upsloping. && .SHORT TERM /SUNDAY NIGHT THROUGH MONDAY/... KEY MESSAGES: - Snow shower expected Sunday night into Monday - Travel impacts could occur in areas under a lake-effect snow band ---------------------------------------------------------------- Falling temperatures and ongoing snow showers are expected Sunday night into early Monday morning. With warm ground temperatures and prior to the system moving through, only a few tenths of an inch (mainly on grass and elevated surfaces) are expected by sunrise on Monday. The upper-level trough will continue to move across the region on Monday. Differences remain in the upper patterns between the GEFS and the Euro with the duration of the NW flow. Differences in the flow would result in differing snow accumulations through Tuesday. Despite these differences, the picture remains the same that NW flow will bring scattered to numerous snow showers across portions of the OH Valley. 850mb temperatures are expected to drop to between -8 to -10 deg C by Monday, while Lake Erie temperatures hover around +12 to +14 deg C. Lake and terrain enhancement will be likely Monday night into Tuesday before flow backs to the W and the most efficient lake and terrain enhancement is turned north of the region. Mesoscale features (such as a reinforcing surface trough) will greatly affect SFC to 850mb flow and thus the positioning, duration, and intensity of any heavier focused lake bands remains low confidence at this time. Despite this, models continue to hint at the likelihood of one or several lake bands yielding enhanced snowfall near and south of Lake Erie. NBM probabilities for advisory level snowfall continue to fluctuate. Currently, there is a 40%-60% north of I-80 while the PA and WV ridges probabilities remain between 30%-40%. We will continue to monitor the evolution of this system and pattern over the coming forecast periods. && .LONG TERM /MONDAY NIGHT THROUGH SATURDAY/... KEY MESSAGES: - Cold temperatures and snow showers continue Tuesday - Unsettled Wednesday and Thursday with occasional rain/snow chances mainly north of Pittsburgh - Apparent temperatures in the teens Tuesday morning ------------------------------------------------------------------- The surface trough is will shift to the northeast of the area on Tuesday, as boundary layer flow backs to the SW and snow chances decrease through the day. Broad upper troughing is then expected to persist across areas from the Upper Midwest into New England. Occasional rain/snow chances will be possible, mainly north of PIT, as individual shortwaves rotate through the trough. Temperatures are expected to be 15 to 20 degrees below average Monday and Tuesday, before moderating some by mid week. && .AVIATION /00Z SUNDAY THROUGH THURSDAY/... Complex and meteorologically diverse weather pattern expected for area terminals through the TAF period, creating few periods of high confidence and potential for wide restriction variability. Height rises ahead of an approaching shortwave trough overnight should favor VFR with streams of cirrus aloft through 12z; however, a stalled boundary near FKL/DUJ that may fluctuate slightly in positioning will favor MVFR to IFR cigs north of its positioning. Additionally, various hi-res guidance and cross- over methodology suggests a potential area of LIFR stratus/fog developing near ZZV through PIT prior to dawn. Due to incoming cirrus, kept probability of occurrence low. Crossing of an initial shortwave and surface low center will favor a band of light to moderate rain that moves NE between 12z-18z and should foster MVFR/IFR cigs. Variance in cig heights will be highest east of PIT based on low center position, meaning VFR to IFR heights are all a possibility. On and off light rain showers are favored after the initial wave, trending toward a drier afternoon, but a crossing surface cold front should foster a westerly wind shift and downward trend toward IFR cigs. Outlook... Deepening of the upper trough Sunday night into monday will create areas of precipitation with widespread MVFR/IFR conditions while beginning a northwest-to-southeast precipitation type changeover to snow. Variation in the upper trough path for Monday remains high, but steepening lapse rates favors lifting afternoon cigs while increasing chances for convective snow showers that could rapidly reduce visibility. Development of more lake effect bands is more likely to occur Monday night into Tuesday of which narrow bands of IFR and lower restrictions are likely with the heavy snow. Height rises and dry advection should provide areawide improvements Tuesday afternoon into Wednesday, remaining for VFR through end of the week (save for any lingering lake enhancement for NW PA). && .PBZ WATCHES/WARNINGS/ADVISORIES... PA...None. OH...None. WV...None. && $$ SYNOPSIS...Hefferan NEAR TERM...Hefferan SHORT TERM...88/Lupo LONG TERM...Lupo/AK AVIATION...Frazier