004 FXUS61 KPBZ 250735 AFDPBZArea Forecast Discussion National Weather Service Pittsburgh PA 335 AM EDT Thu Sep 25 2025
.SYNOPSIS... Widespread precipitation chances today, diminishing during the late afternoon and evening. Drier conditions expected over the weekend with a building ridge over the Ohio River Valley.
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.NEAR TERM /THROUGH TODAY/... KEY MESSAGES:
- Patchy fog this morning - Precipitation most widespread during the morning - Marginal risk of flooding mainly south and east of Pittsburgh ---------------------------------------------------------------
An upper low over the northern lower peninsula of Michigan continues to be the dominant forecast feature. Patchy dense fog will diminish by mid-morning and at this time, current coverage does not warrant any advisories.
Rain will become more widespread and moderate at times today ahead and along of a crossing cold front and associated surface low. The highest rainfall rates are likely between mid- morning and mid- afternoon as the surface low crosses directly across or just north of the forecast area.
WPC has expanded the Marginal Risk to include areas roughly north up to I-80 for today. Fortunately (if it verifies) latest hi-res and ensemble guidance leans towards the highest precipitation amount roughly south of a line running from Dubois-->Pittsburgh-->Zanesville. Along the same line, FFG values are higher notably to the south and lower to the north, so hopefully the highest precipitation amounts trend south. The highest total observed amounts over the past 72 hours are along and north of the above mentioned line. So if heavier precipitation trends along or north of that line, that may be the area that has the highest potential for seeing any flood impacts.
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.SHORT TERM /TONIGHT THROUGH 6 PM FRIDAY/... KEY MESSAGES:
- Shower chances taper off this evening - Drier, warmer on Friday ----------------------------------------------------------------
As the trough axis shifts east out of the Great Lakes, precipitation chances will taper off from west to east this evening, east of the ridges by around midnight. Increasing mid- and upper-level dry air will keep any remaining precipitation low in coverage and light overnight.
Friday will be largely dry as shortwave ridging transitions over the region, which will also increase daytime highs back up close to normal.
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.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/... KEY MESSAGES:
- Mostly dry weather and seasonable temperatures into next week.
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A weak closed low north of the Mississippi River Valley could possibly bring some light shower activity across the West Virginia ridges and the Laurel Highlands over the weekend as it slowly transitions northeast. Latest ensemble guidance gives a 40% chance of measurable rain over the ridges to a 20% chance in PGH over a 6hr period on Saturday, with lower probabilities on Sunday. Lesser probabilities are forecast north and west.
A broad ridge across the Great Lakes and Ohio River Valley looks to bring a return of quiet weather heading into next week.
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.AVIATION /06Z THURSDAY THROUGH MONDAY/... Expect widespread IFR/LIFR in fog and stratus overnight with low level moisture in place. Surface low pressure will track newd across the Upper Ohio Valley region today, with another round of showers and continued IFR conditions. Rain should gradually taper off during the afternoon as the surface low tracks across central PA/srn NY, with a gradual improvement to MVFR cigs expected.
A brief period of VFR is possible late this afternoon and evening, before IFR fog and stratus again develop tonight with low level moisture in place.
.OUTLOOK.... Fog and stratus is likely Friday morning, before VFR returns under building high pressure. Restrictions and showers are possible, mainly S-E of PIT, Saturday and Sunday with a crossing upper trough. VFR is expected Monday under high pressure.
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.PBZ WATCHES/WARNINGS/ADVISORIES... PA...None. OH...None. WV...None.
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SYNOPSIS...88 NEAR TERM...88 SHORT TERM...88 LONG TERM...88 AVIATION...WM
NWS PBZ Office Area Forecast Discussion