Area Forecast Discussion
Issued by NWS Pittsburgh, PA
Issued by NWS Pittsburgh, PA
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809 FXUS61 KPBZ 081919 AFDPBZ Area Forecast Discussion National Weather Service Pittsburgh PA 219 PM EST Sat Nov 8 2025 .SYNOPSIS... A brief period of dry weather is expected this afternoon before another shortwave trough dives into the region tonight. This will bring a round of showers on Sunday, changing to snow showers Sunday night. && .NEAR TERM /THROUGH SUNDAY/... KEY MESSAGES: - Dry conditions through the afternoon - Rain chances increase tonight into Sunday --------------------------------------------------------------- A shortwave ridge transitioning over the region today will result in dry conditions under increasing subsidence. After some clearing and drying out from the dense fog earlier, cloud cover has cleared a bit as well. This has allowed temperatures to warm into the mid and upper 50s. Heading into tonight, the deepening upper trough is progged to dig across the Upper Midwest and western Great Lakes overnight and Sunday. Meanwhile, surface low pressure will deepen as it tracks up the Ohio River Valley. While there is a minimal chance of brief light rain across northern zones this evening with a weak shortwave, rain chances will substantially ramp up across much of the area Sunday morning as the surface low traverses the eastern Great Lakes and drags its trailing cold front across the region. Precipitation on Sunday will mainly be liquid with the NBM probs advertising a 60% to 80% probability of rainfall amounts topping 0.25 inches, but this is mainly in the northwestern portions of the forecast area. Coverage should become more scattered behind the front, but showers will persist as the upper trough continues to deepen and approach from the west. && .SHORT TERM /SUNDAY NIGHT/... KEY MESSAGES: - Rain chances increase Sunday morning - Colder with rain mixing with/changing to snow Sunday night ---------------------------------------------------------------- Overnight and into Sunday, a deepening upper trough is progged to dig across the Upper Midwest and western Great Lakes while the surface low (over southern Illinois) will deepen as it tracks up the Ohio River Valley. Rain chances will substantially ramp up across much of the area Sunday morning as the surface low traverses the eastern Great Lakes and drags a trailing cold front across the region tomorrow afternoon. Post-frontal passage, precipitation coverage should become more scattered, however, showers will persist as the upper trough continues to deepen as it approaches the region. Temperatures drop quickly Sunday night when rain mixes with and then transitions to snow. 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.&& .LONG TERM /MONDAY THROUGH FRIDAY/... KEY MESSAGES: - Much colder with snow showers Monday into Tuesday - Accumulation possible mainly north of I-80 and in the ridges - Unsettled Wednesday and Thursday with occasional rain/snow chances mainly north of Pittsburgh - Apparent temperatures in the teens Tuesday morning ------------------------------------------------------------------- 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. 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 /19Z SATURDAY THROUGH THURSDAY/... Passing high pressure this afternoon will allow for some VFR readings across the area. Another shortwave trough passing through the area tonight will bring showers and some deteriorating flight conditions overnight, with just about every terminal going below IFR through 06Z to the end of the TAF period. There may be some improvement to MVFR by noon tomorrow but overall, every terminal will be impacted. Winds will shift to the west late tonight with some gusts reaching 20 knots at some of the terminals. Outlook... Restrictions are likely to continue Sunday night as rain showers change to snow showers allowing for lower cigs expected. This will persists through the day on Monday as well with some restrictions possible on Tuesday. && .PBZ WATCHES/WARNINGS/ADVISORIES... PA...None. OH...None. WV...None. && $$ SYNOPSIS...Shallenberger NEAR TERM...Shallenberger SHORT TERM...88/Lupo LONG TERM...Lupo/AK AVIATION...Shallenberger