Area Forecast Discussion
Issued by NWS Pittsburgh, PA
Issued by NWS Pittsburgh, PA
123 FXUS61 KPBZ 290600 AFDPBZ Area Forecast Discussion National Weather Service Pittsburgh PA 200 AM EDT Sat Aug 29 2026 .WHAT HAS CHANGED... Some increase in shower and thunderstorm chances were included near and north of I-80 Sunday night into Monday. Otherwise, no major changes were made to the latest forecast. && .KEY MESSAGES... 1) Dry weather through the weekend 2) Heat, humidity and shower/thunderstorm chances return next week && .DISCUSSION... KEY MESSAGE 1... Surface high pressure was centered across western PA early this morning. The high will continue to move east through Sunday, maintaining dry weather across the region. Highs should be near seasonable levels today, with low humidity. Rising 500mb heights, and a veering flow from east to south, should result in warmer temperatures and slightly higher humidity on Sunday. KEY MESSAGE 2... A ridge is progged to build eastward from the central CONUS from late Sunday into the middle of next week. Models differ on the placement and northern extent of the ridge, especially early in the week. Individual shortwaves are expected to track across the northern periphery of the ridge, and the strength/placement of the ridge will have an impact on how far south this activity reaches. In general, the first shortwave could spread shower and thunderstorm chances to areas near and north of I-80 Sunday night into Monday. The ridge is expected to continue advancing eastward, strengthening across the Upper Ohio Valley region later Monday into Tuesday. If this scenario occur, it would likely suppress most of the convection across our area. The 500mb heights should peak across the Upper Ohio Valley region later Tuesday through part of Wednesday, before the ridge begins to break down. In general, expect shower and thunderstorm chances to increase as the ridge breaks down, and as a shortwave trough approaches late Wednesday into Thursday. The latest ML guidance indicates some potential for severe storms especially Wednesday into Thursday, though this will be highly dependent on the placement of the ridge, timing of its breakdown, and timing of the shortwave. Rising 500mb heights and SW flow should result in warming temperatures through mid week, with highs around 90 Tuesday and Wednesday for most locations outside of the higher terrain. This will also depend on the placement and strength of the ridge. The heat and humidity could result in heat index values in the mid to upper 90s both of those days. Temperatures should begin to moderate by late week. && .AVIATION /06Z SATURDAY THROUGH WEDNESDAY/... Other than early morning MVFR to IFR river valley fog, expect VFR conditions through the TAF period as surface high pressure tracks east across the region. Increasing high clouds are expected with warm advection aloft. Outlook... VFR is expected for much of the area through Tuesday as an upper level ridge builds across the region. Shower and thunderstorm chances are possible mainly for FKL and DUJ Sunday night into Monday as a shortwave trough moves across the northern periphery of the ridge. Shower and thunderstorm chances should increase by late Wednesday as the ridge begins to break down, and a shortwave trough approaches. && .PBZ WATCHES/WARNINGS/ADVISORIES... PA...None. OH...None. WV...None. && $$ DISCUSSION...WM AVIATION...WM