Area Forecast Discussion
Issued by NWS Pittsburgh, PA
Issued by NWS Pittsburgh, PA
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081 FXUS61 KPBZ 011752 AFDPBZ Area Forecast Discussion National Weather Service Pittsburgh PA 152 PM EDT Thu Oct 1 2026 .WHAT HAS CHANGED... No major changes to the forecast through the weekend. Frost potential early next week is increasing a bit, especially northeast of Pittsburgh. && .KEY MESSAGES... 1) Showers return with a Friday cold front, with no notable threats for heavy rain or severe thunderstorms. 2) Cooler and mainly dry from this weekend into early next week. Frost is a possibility Tuesday and Wednesday mornings, mainly northeast of Pittsburgh. && .DISCUSSION... KEY MESSAGE 1... Mid-level ridging remains in place across the Upper Ohio Valley this afternoon, leading to plenty of sunshine and above- normal temperatures, with many locations expected to reach or exceed 80 degrees for maximums. Also today, a Central Plans closed low begins to degrade with time, eventually ejecting as a shortwave trough across the Ohio Vally through Friday. This will help to push a cold front across the region tomorrow, with rain chances increasing ahead of it starting after midnight to the northwest of Pittsburgh, with the main period of rain during the daylight hours and into the early evening. Southwest flow ahead of the boundary will promote some moistening of the column, with precipitable water values increasing to around 1.7 inches immediately ahead of the boundary, which represents top-end climatology. Even so, the overall weak forcing and unfavorable frontal timing will work against a threat of heavy rain. HREF probabilities of 24-hour rain totals exceeding 0.50 inch are less than 10 percent over most of our region, with only a few bands of 20 to 40 percent potential. Plus, while 0-6km shear should range from 40 to 50 knots during FROPA, SBCAPE will likely be limited to around 200 J/kg or less. What instability there is is packed close to the surface, with most model soundings suggesting updrafts will top out below -10C, limiting any lightning potential. So, it is appropriate that the SPC convective outlook for Friday does not even include our area in a risk for "general" thunderstorms. Most rain will end Friday evening with the departure of the front, although a few showers may linger in the ridges southeast of Pittsburgh into Saturday morning. KEY MESSAGE 2... Model ensembles indicate broad upper troughing should persist across the NE CONUS from the weekend into the middle of next week. A southern stream shortwave could bring a few showers to areas south and east of Pittsburgh on Sunday. This disturbance would be followed by an influx of cooler air into the region, dropping temperatures below climatology early next week while another run of dry weather begins thanks to high pressure. One thing to watch will be the potential for frost both Tuesday and Wednesday mornings to the northeast of Pittsburgh, as well as in the usual Laurel Highland/northern West Virginia cold spots. The NBM paints a 35 to 75 percent chance of low temperatures colder than 37 degrees north of US-422 both mornings - which would be chilly enough for at least patchy frost given clear and calm overnight conditions. Temperatures from Wednesday on should build back towards more seasonal values. && .AVIATION /18Z THURSDAY THROUGH TUESDAY/... Prevailing VFR anticipated through the remainder of today and tonight with some high level clouds generally from KPIT northward. Wind will be from the SSW around 10kts with some gusts to 15kts possible. Cold front will make it`s approach toward morning on Friday. Restrictions are timed based on the latest ensemble guidance, with low MVFR/IFR likely with rain across much of the terminals through the period from about 12z onward. Tried to be a bit more optimistic at some locations, with using PROB30 groups to highlight IFR conditions based on model data and current upstream conditions. Worst case would be a 6-8 hour period of IFR ceilings with isolated instances of IFR visibility embedded in pockets of heavier rain. Conditions should improve with the frontal passage by late afternoon, though this is not reflected in the latest TAF issuance as of yet. Outlook... Boundary may stall just south of I-70 with some potential restrictions Sat and Sun at the southern terminals. Otherwise, VFR is progged outside of any morning fog. && .PBZ WATCHES/WARNINGS/ADVISORIES... PA...None. OH...None. WV...None. && $$ DISCUSSION...CL AVIATION...34