Alert archive / Pennsylvania / Flash Flood Warnings in 2025

Flash Flood Warning 12, NWS Pittsburgh, PA

May 21, 2025Butler County, Lawrence County, Pennsylvania

NWS Pittsburgh, PA issued this flash flood warning at May 21, 2025, 8:12 PM EDT for Butler County, Lawrence County, Pennsylvania. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: May 21, 2025, 8:12 PM EDT (00:12 UTC)
Expired: May 21, 2025, 11:15 PM EDT
In force: 3 hr
Issued by: NWS Pittsburgh, PA
Area: Storm-based polygon
Flood severity: None

Counties Butler County, PA, Lawrence County, PA

The radar

The Pittsburgh radar (KPBZ), 47 km from the middle of the area, began a volume at 00:11 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Buffalo Intl Airport, NY (KBUF), launched 00:00Z, 0.2 hours before the alert went out and 250 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 588 m above ground
0-6 km bulk shear: 20 kt
0-1 km storm-relative helicity: 179 m²/s²
0-3 km storm-relative helicity: 278 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this flash flood warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Pittsburgh, PA wrote its last area forecast discussion before this flash flood warning went out at May 21, 6:48 PM EDT, 1 hour 24 minutes earlier.

Area forecast discussion, May 21, 6:48 PM EDT, 1 hour 24 minutes before

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Hazardous weather outlook, May 21, 6:34 PM EDT, 1 hour 38 minutes before

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In the hours before

Local storm report, May 21, 5:31 PM EDT, 2 hours 41 minutes before

Preliminary Local Storm Report
National Weather Service Pittsburgh PA
531 PM EDT Wed May 21 2025

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0505 PM     Flash Flood      East Moravia            40.93N  80.37W
05/21/2025                   Lawrence           PA   911 Call Center

            Report of Industrial Street closed near Eastbrook Road
            due to flooding.

&&

Event Number PBZ2507712

JF

Local storm report, May 21, 5:52 PM EDT, 2 hours 20 minutes before

Preliminary Local Storm Report
National Weather Service Pittsburgh PA
552 PM EDT Wed May 21 2025

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0546 PM     Flash Flood      Beechview               40.42N  80.03W
05/21/2025                   Allegheny          PA   911 Call Center

            Report of Crane Ave flooded at Route 51 due to heavy
            rains.

&&

Event Number PBZ2507713

JF

Local storm report, May 21, 5:53 PM EDT, 2 hours 19 minutes before

Preliminary Local Storm Report
National Weather Service Pittsburgh PA
553 PM EDT Wed May 21 2025

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0550 PM     Flash Flood      2 WNW Mount Oliver      40.42N 80.01W
05/21/2025                   Allegheny          PA   Public

            Crane Avenue at Route 51 is flooding.

&&

Local storm report, May 21, 6:03 PM EDT, 2 hours 9 minutes before

Preliminary Local Storm Report
National Weather Service Pittsburgh PA
603 PM EDT Wed May 21 2025

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0519 PM     Tstm Wnd Dmg     Finleyville             40.26N  80.00W
05/21/2025                   Washington         PA   Public

            Report and photo of 2 trees uprooted. Timing estimated
            based on radar.

&&

Event Number PBZ2507715

JF

Local storm report, May 21, 6:07 PM EDT, 2 hours 5 minutes before

Preliminary Local Storm Report
National Weather Service Pittsburgh PA
607 PM EDT Wed May 21 2025

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0519 PM     Tstm Wnd Dmg     Finleyville             40.25N  80.00W
05/21/2025                   Washington         PA   Public

            Photo showing siding pulled off building in
            Finleyville. Exact location TBD. Timing estimated based
            on radar.

&&

Event Number PBZ2507716

JF

Local storm report, May 21, 7:01 PM EDT, 1 hour 11 minutes before

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Nearby

Flash Flood Warnings in Pennsylvania, 2025 Every flash flood warning in 2025

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.