565 FXUS61 KPBZ 270556 AFDPBZ Area Forecast Discussion National Weather Service Pittsburgh PA 156 AM EDT Sun Jul 27 2025 .SYNOPSIS... Showers and thunderstorms are expected today with a trough of low pressure. Hot and humid weather will return for the first half of the upcoming week. Showers and thunderstorms return with a mid week cold front, with cooler and less humid weather to end the week. && .NEAR TERM /THROUGH TODAY/... KEY MESSAGES: - Showers and thunderstorms continue today - Locally heavy rainfall possible - Marginal Risk for severe storms over SW PA/Nrn WV --------------------------------------------------------------- A shortwave trough will track SE across the Upper Ohio Valley region today. Veering upper level flow will also push a surface trough back south across the area today. This will be the focus for additional showers and thunderstorms across the region today. 0-6km shear is progged to range from 20-30kt, with ML CAPE ranging from 1500-2000 j/kg. There is some limited dry mid level air progged this afternoon as well. Similar to Saturday, any more organized storms could produce damaging wind gusts with the minimal shear and limited dry air aloft. PWATS are progged to range from 1.8 to 2.0 again today, resulting in a locally heavy rainfall potential. This could again result in localized flash flooding, especially for area from Pittsburgh south. At this time, it appears the flood threat will be ocalized enough to preclude a flood watch. Warm and humid conditions will continue, though temperatures are expected to be a few degrees lower than on Saturday. && .SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/... KEY MESSAGES: - Showers and thunderstorms end tonight - Limited shower/storm chances Monday, mainly across OH - Mainly dry Tuesday - Hot and humid through the period ---------------------------------------------------------------- The shortwave trough is expected to exit the region from N-S later this evening and overnight. Showers and thunderstorms will also diminish as the trough exits. Partial clearing is initially expected overnight as low level ridging builds in. With low level moisture in place, areas of fog and stratus should develop as the mid/high level clouds clear out. The fog and stratus should mix out Monday morning after sunrise. Mainly dry weather is expected for much of the area during the day as surface high pressure builds in from the north. The Upper Ohio Valley region is expected to be under NW flow aloft, and a weak shortwave embedded in this flow could spark a few showers and thunderstorms Monday afternoon, mainly across Ohio, as it tracks SE. An upper high is progged to build across the Central CONUS on Tuesday, with the Upper Ohio Valley region on the NE periphery of the high. Model soundings indicate the region should be capped under warm air aloft, with generally dry conditions expected. Highs are expected to be in the lower 90s for much of the area, with heat index values ranging from 95 to 100. Dry and warm weather is expected to continue Tuesday night under the weak surface high. Some models indicate a shortwave in the NW flow , though the consensus is this will stay far enough N to keep the area dry. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... KEY MESSAGES: - Hot and humid Wednesday - Showers/storms return Wednesday and Thursday - Cooler and less humid to end the week ------------------------------------------------------------------- The upper high over the Central CONUS is expected to retrograde to the west beginning mid week. A more amplified pattern is then expected across the northern CONUS, with a trough and surface cold front approaching the Upper Ohio Valley region late Wednesday. Shower and thunderstorm chances will return by Wednesday afternoon as the shortwave and cold front approach. Shower and thunderstorm chances continue Wednesday night into Thursday as they cross the Upper Ohio Valley region. Dry weather is expected to return Thursday night through Saturday, as surface high pressure builds under NW flow aloft. This should result in cooler and less humid conditions for late week into the weekend. && .AVIATION /06Z SUNDAY THROUGH THURSDAY/... Fog development this morning should be patchy and MVFR based off latest observations and forecast soundings with cloud coverage mitigating development. However, any prolonged clearings could allow for more substantial fog/low stratus to develop given moist boundary layer. Additional convection is expected ahead of a dropping frontal boundary through 00z Sunday evening with current modeling favoring western PA into northern WV seeing the stronger storms. Outlook... Daily showers and thunderstorm chances, with restriction chances, will continue into early next week with a series of disturbances. && .PBZ WATCHES/WARNINGS/ADVISORIES... PA...None. OH...None. WV...None. && $$ SYNOPSIS...WM NEAR TERM...WM SHORT TERM...WM LONG TERM...WM AVIATION...Frazier/88