715 FXUS61 KPBZ 230145 AAA AFDPBZArea Forecast Discussion...UPDATED National Weather Service Pittsburgh PA 945 PM EDT Mon Sep 22 2025
.SYNOPSIS... Showers and a few thunderstorms will continue tonight. Rain chances remain elevated throughout week with slightly above- average temperatures.
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.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... KEY MESSAGES:
- Showers and a few thunderstorms tonight ---------------------------------------------------------------
Showers and embedded thunderstorms will continue to move across the region tonight. The latest mesoanalysis shows shear has increase, helping to maintain the showers/storms, though instability has waned enough to preclude a severe storm potential for the rest of the evening.
Moist SW flow and additional shortwave supported lift should maintain showers overnight as well. An isolated thunderstorm is possible, though elevated instability should be minimal. Overnight lows are expected to be around 10 degrees above average with the cloud cover and showers.
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.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY/... KEY MESSAGES:
- Probabilities remain elevated for rain on Tuesday/Wednesday
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Confidence remains high that rain chances will persist Tuesday into Wednesday as a trough lingers over the Ohio River Valley. With continuing southwest flow, as the trough axis remains positioned west of the region, probability of measurable rainfall is above 70%. For Tuesday morning, probabilities are elevated (between 40-50%) for 1 inch of rainfall for areas north of Pittsburgh due to the position of the left exit region of the upper-level jet.
Compared to Monday, the potential for strong storms is considered low due to the lack of instability. Lightning will likely be the only threat associated with any developing thunderstorm.
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.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... KEY MESSAGES:
- Elevated precipitation chances through Friday - Near average temperatures - Drier conditions expected over the weekend ------------------------------------------------------------------
An upper-level trough will continue to influence the region late week, keeping rain chances in place through Friday. The greatest potential for heavier rainfall is expected Thursday morning into Thursday evening as the low tracks into western Pennsylvania. By late Thursday, increasing mid- and upper-level dry air will move in from the west. While lingering low-level moisture will still support a few scattered rain showers, the risk for heavier rainfall rates will diminish.
Looking ahead, long-range ensembles suggests a ridge will build over the Ohio River Valley from Friday through Sunday, bringing decreasing precipitation chances. Afternoon high temperatures are projected to run about 5 degrees above average, topping out in the mid-70s. Overnight lows should remain near average, especially if clear skies favor radiational cooling in the wake of passing cold front.
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.AVIATION /02Z TUESDAY THROUGH SATURDAY/... Areas of showers and thunderstorms will continue to affect the region this evening. The first area continues to weaken, though a second line of showers/storms is expected this evening/overnight with an approaching shortwave trough. Maintained predominant thunder, with tempo reduced restrictions, through this evening as this activity crosses. After the second line of storms this evening, expect a deterioration to MVFR, and then IFR, with increasing low level moisture in rain.
This rain and IFR conditions will continue into Tuesday as a second trough crosses the region. Expect rain to taper off from west to east later in the day, with some improvement to MVFR cigs.
.OUTLOOK.... Fog and stratus restrictions are possible Tuesday night. Improvement to VFR is expected early Wednesday before approaching low pressure brings restrictions and rain back to the region later Wednesday afternoon into Thursday. Building high pressure should return VFR later Friday through Saturday.
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.PBZ WATCHES/WARNINGS/ADVISORIES... PA...None. OH...None. WV...None.
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SYNOPSIS...WM/Hefferan NEAR TERM...WM SHORT TERM...Hefferan LONG TERM...Hefferan AVIATION...WM
NWS PBZ Office Area Forecast Discussion