


Area Forecast Discussion
Issued by NWS Pittsburgh, PA
Issued by NWS Pittsburgh, PA
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585 FXUS61 KPBZ 150525 AFDPBZ Area Forecast Discussion National Weather Service Pittsburgh PA 125 AM EDT Wed Oct 15 2025 .SYNOPSIS... Dry conditions and near normal temperatures are expected through Friday. Morning frost and localized freeze conditions are possible both Thursday and Friday. Rain may return for portions of the region Saturday before more widespread rain with a cold front Saturday night and Sunday. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... KEY MESSAGES: - A dry cold front will cross overnight and increase cloud cover. --------------------------------------------------------------- Latest surface analysis shows a weak/dry cold front already through the forecast area. Cold advection behind this feature should allow an increase in stratocu this morning. This cloud cover and delayed arrival of cooler air means overnight low temperature remains near to slightly above the daily average. && .SHORT TERM /6 AM THIS MORNING THROUGH THURSDAY NIGHT/... KEY MESSAGES: - High confidence in dry conditions - Frost/freeze conditions appear increasingly likely Wednesday night and Thursday night ---------------------------------------------------------------- There is high confidence in dry conditions persisting Wednesday and Thursday as the local area remains under an area of northwest flow, sandwiched between a broad upper ridge over the central CONUS and a deepening longwave trough over the western Atlantic. Cooler air will filter into the area in response to the amplifying pattern, with high temperatures each afternoon returning to near seasonal levels (low 60s for the Pittsburgh area). As the surface high shifts eastward and centers more over the lower Great Lakes, we will see drier air and calming winds which should result in very efficient nighttime radiational cooling. A frost/freeze remains possible both Wednesday and Thursday nights. The most likely areas to experience frost will be north and east of Pittsburgh, where NBM probabilities are near 100 percent for low temperatures dropping to 36F or lower (a decent proxy for frost formation in situations like this). Elsewhere across eastern OH, northern WV, and southwestern PA, locations outside of the immediate Ohio River valley generally see frost probabilities ranging from 40 to 60 percent. With respect to freeze conditions, NBM probabilities for low temperatures at or below 32F are as much as 60-90% for areas north and east of Pittsburgh and the Laurel Highlands. Therefore, expect some combination of frost/freeze headlines Wednesday night. There are higher probabilities for frost/freeze conditions across a larger portion of the area Thursday night, but any headlines for that period will be dictated by the expanse and magnitude of frost/freeze conditions Wednesday night, as the growing season may end for many locations on Thursday. && .LONG TERM /FRIDAY THROUGH TUESDAY/... KEY MESSAGES: - Above average temperatures return Friday into the weekend - Rain chances increasing late this weekend ------------------------------------------------------------------- The central CONUS ridge shifts eastward Friday through the weekend, centering over the local area early Saturday and over the eastern seaboard on Sunday as an upstream trough deepens over the upper Midwest and Great Lakes. Mostly dry conditions can be expected to start the period, though guidance does suggest a low chance for decaying rain showers to make their way across mainly the northern half of the area Friday night into early Saturday morning. However, confidence in this occuring remains low as ensembles are currently in a rather significant disagreement regarding the magnitude of dry air below 700mb and thus the amount of sub-cloud evaporation. The current NBM mean maintains low (20-30%) PoPs north of I-70 which seems reasonable at this time given the uncertainty. Regardless, if precipitation occurs it would be very light, with even the LREF 90th percentile topping out at only a tenth of an inch of total rainfall during that period (and primarily focused north of Pittsburgh). As the central CONUS trough continues to advance eastward, it pushes the upper ridge out over the western Atlantic, returning the local area to unsettled weather and increasing chances for showers and thunderstorms Saturday night through Sunday night. Current ensemble guidance indicates 24-hour totals generally ranging from 0.25" to 0.75" across the region within the 25th to 75th percentile range. However, there continues to be some outlying members that indicate a non-zero chance for higher amounts approaching 1.0 to 1.25 inches in some locations. Temperatures trend warmer Friday through Sunday, climbing back above seasonal normals with the warmest day looking to be Saturday as highs climb into the low to mid 70s. A cold front on Sunday brings temperatures back down to near seasonal levels to start next week. && .AVIATION /05Z WEDNESDAY THROUGH SUNDAY/... Much of the area through dawn will be dealing with just some upper level cloud cover. However, conditions at FKL and DUJ and to some extent, LBE, will be dealing with some IFR/MVFR cigs through dawn. Expect much of this to lift by late morning. The rest of the terminals should be VFR through the period. Light and variable winds will continue as well. Dry advection and subsidence will erode any MVFR stratus by Wednesday afternoon (80-90% confidence of VFR by 18z). .OUTLOOK... Surface high pressure with height rises aloft favor VFR into Saturday morning before a series of shortwaves ahead of the next cold front bring increased rain and restriction chances. && .PBZ WATCHES/WARNINGS/ADVISORIES... PA...Frost Advisory from midnight tonight to 9 AM EDT Thursday for PAZ007>009-013>016-020>022-029-031-073>078. OH...Frost Advisory from midnight tonight to 9 AM EDT Thursday for OHZ039>041-049-050. WV...Frost Advisory from midnight tonight to 9 AM EDT Thursday for WVZ001-002-509>514. && $$ SYNOPSIS...Frazier/88 NEAR TERM...Rackley/Frazier/88 SHORT TERM...Cermak LONG TERM...Cermak AVIATION...Shallenberger