Alert archive / Pennsylvania / Flash Flood Warnings in 2024

Flash Flood Warning 9, NWS Pittsburgh, PA

April 11, 20244 counties in Pennsylvania; Marion County, Monongalia County, Wetzel County, West Virginia

NWS Pittsburgh, PA issued this flash flood warning at Apr 11, 2024, 7:14 PM EDT for 4 counties in Pennsylvania; Marion County, Monongalia County, Wetzel County, West Virginia. It was in force for 6 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: Apr 11, 2024, 7:14 PM EDT (23:14 UTC)
Expired: Apr 12, 2024, 12:52 AM EDT
In force: 6 hr
Issued by: NWS Pittsburgh, PA
Area: Storm-based polygon
Flood severity: None

Counties Allegheny County, PA, Fayette County, PA, Greene County, PA, Washington County, PA, Marion County, WV, Monongalia County, WV, Wetzel County, WV

The radar

The Pittsburgh radar (KPBZ), 72 km from the middle of the area, began a volume at 23:13 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

Pittsburgh, PA (KPIT), launched 12:00Z, 11.2 hours before the alert went out and 59 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: 22 J/kg
Mixed-layer CIN: -46 J/kg
Mixed-layer LCL: 1066 m above ground
0-6 km bulk shear: 41 kt
0-1 km storm-relative helicity: 284 m²/s²
0-3 km storm-relative helicity: 238 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 Apr 11, 6:42 PM EDT, 32 minutes earlier.

Area forecast discussion, Apr 11, 6:42 PM EDT, 32 minutes before

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Hazardous weather outlook, Apr 11, 6:46 PM EDT, 28 minutes before

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In the hours before

Local storm report, Apr 11, 6:56 PM EDT, 18 minutes before

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Local storm report, Apr 11, 6:57 PM EDT, 17 minutes before

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Local storm report, Apr 11, 7:00 PM EDT, 14 minutes before

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Local storm report, Apr 11, 7:01 PM EDT, 13 minutes before

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Local storm report, Apr 11, 7:05 PM EDT, 9 minutes before

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Local storm report, Apr 11, 7:07 PM EDT, 7 minutes before

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The office that day

Everything else NWS Pittsburgh, PA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 11, 10:00 AM EDT	Flood Watch	PBZ	Allegheny, Armstrong, Beaver, Butler, Clarion, Fayette and 9 more	16 hr
Apr 11, 11:01 AM EDT	River Flood Advisory	PBZ	Allegheny	23 hr
Apr 11, 5:12 PM EDT	Flash Flood Warning	PBZ	Greene, Washington	8 hr
Apr 11, 5:32 PM EDT	Flash Flood Warning	PBZ	Allegheny, Beaver, Butler, Lawrence, Washington	7 hr
Apr 11, 5:58 PM EDT	Flash Flood Warning	PBZ	Allegheny, Greene, Washington	7 hr
Apr 11, 7:07 PM EDT	Flash Flood Warning EmergencyCatastrophic damage threat	PBZ	Allegheny, Washington	5 hr
Apr 11, 10:44 AM EDT	River Flood Watch	PBZ	Guernsey	12 hr

Nearby

Flash Flood Warnings in Pennsylvania, 2024 Flash Flood Warnings in West Virginia, 2024 Every flash flood warning in 2024

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.