Alert archive / Pennsylvania / Flash Flood Warnings in 2024

Flash Flood Warning 11, NWS Pittsburgh, PA

April 11, 20247 counties in Pennsylvania; Monongalia County, Preston County, West Virginia

NWS Pittsburgh, PA issued this flash flood warning at Apr 11, 2024, 9:10 PM EDT for 7 counties in Pennsylvania; Monongalia County, Preston County, West Virginia. It was in force for 4 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, 9:10 PM EDT (01:10 UTC)
Expired: Apr 12, 2024, 12:53 AM EDT
In force: 4 hr
Issued by: NWS Pittsburgh, PA
Area: Storm-based polygon
Flood severity: None

Counties Allegheny County, PA, Armstrong County, PA, Butler County, PA, Fayette County, PA, Greene County, PA, Indiana County, PA, Westmoreland County, PA, Monongalia County, WV, Preston County, WV

The radar

The Pittsburgh radar (KPBZ), 54 km from the middle of the area, began a volume at 01:14 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 00:00Z, 1.2 hours before the alert went out and 38 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: 1 J/kg
Mixed-layer CIN: -77 J/kg
Mixed-layer LCL: 673 m above ground
0-6 km bulk shear: 50 kt
0-1 km storm-relative helicity: -32 m²/s²
0-3 km storm-relative helicity: 58 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, 7:43 PM EDT, 1 hour 27 minutes earlier.

Area forecast discussion, Apr 11, 7:43 PM EDT, 1 hour 27 minutes before

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Hazardous weather outlook, Apr 11, 6:46 PM EDT, 2 hours 24 minutes before

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In the hours before

Local storm report, Apr 11, 7:30 PM EDT, 1 hour 40 minutes before

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Local storm report, Apr 11, 7:32 PM EDT, 1 hour 38 minutes before

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Local storm report, Apr 11, 7:33 PM EDT, 1 hour 37 minutes before

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Local storm report, Apr 11, 7:38 PM EDT, 1 hour 32 minutes before

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Local storm report, Apr 11, 7:42 PM EDT, 1 hour 28 minutes before

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        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
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Local storm report, Apr 11, 7:46 PM EDT, 1 hour 24 minutes before

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      <p id="message1">
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      <p id="message2">
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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, 9:45 PM EDT	Flash Flood Warning	PBZ	Armstrong, Butler, Clarion, Forest, Lawrence, Mercer and 1 more	3 hr
Apr 12, 12:36 AM EDT	Areal Flood Warning	PBZ	Allegheny, Armstrong, Beaver, Butler, Fayette, Greene and 4 more	25 hr
Apr 12, 12:43 AM EDT	Areal Flood Warning	PBZ	Armstrong, Butler, Clarion, Forest, Lawrence, Mercer and 1 more	31 hr
Apr 12, 3:13 AM EDT	Wind Advisory	PBZ	Allegheny, Armstrong, Beaver, Butler, Clarion, Fayette and 9 more	39 hr
Apr 12, 4:41 AM EDT	River Flood Warning	PBZ	Allegheny	36 hr
Apr 12, 5:50 AM EDT	River Flood Warning	PBZ	Allegheny	30 hr
Apr 12, 5:50 AM EDT	River Flood Warning	PBZ	Beaver	39 hr
Apr 12, 9:52 AM EDT	River Flood Warning	PBZ	Clarion, Forest, Jefferson	13 hr
Apr 12, 11:17 AM EDT	River Flood Warning	PBZ	Beaver	45 hr
Apr 12, 5:50 AM EDT	River Flood Watch	PBZ	Hancock	41 hr
Apr 12, 5:50 AM EDT	River Flood Watch	PBZ	Brooke	44 hr
Apr 12, 5:50 AM EDT	River Flood Warning	PBZ	Marshall	67 hr
Apr 12, 5:50 AM EDT	River Flood Warning	PBZ	Ohio	66 hr
Apr 12, 5:50 AM EDT	River Flood Warning	PBZ	Marshall	62 hr
Apr 12, 5:50 AM EDT	River Flood Warning	PBZ	Ohio	62 hr
Apr 12, 5:50 AM EDT	River Flood Warning	PBZ	Tyler, Wetzel	61 hr
Apr 12, 11:17 AM EDT	River Flood Warning	PBZ	Hancock	46 hr
Apr 12, 11:17 AM EDT	River Flood Warning	PBZ	Brooke	56 hr
Apr 12, 11:17 AM EDT	River Flood Warning	PBZ	Brooke	35 hr
Apr 11, 8:37 PM EDT	Flash Flood Warning	PBZ	Belmont, Guernsey, Harrison, Jefferson, Monroe, Noble	4 hr
Apr 12, 5:50 AM EDT	River Flood Watch	PBZ	Columbiana	44 hr
Apr 12, 11:17 AM EDT	River Flood Warning	PBZ	Columbiana	47 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.