Alert archive / Pennsylvania / Areal Flood Warnings in 2021

Areal Flood Warning 8, NWS Pittsburgh, PA

August 12, 20215 counties in Pennsylvania; Brooke County, Hancock County, West Virginia; Jefferson County, Ohio

NWS Pittsburgh, PA issued this areal flood warning at Aug 12, 2021, 11:43 PM EDT for 5 counties in Pennsylvania; Brooke County, Hancock County, West Virginia; Jefferson County, Ohio. It was in force for 92 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Aug 12, 2021, 11:43 PM EDT (03:43 UTC)
Expired: Aug 13, 2021, 1:15 AM EDT
In force: 92 min
Issued by: NWS Pittsburgh, PA
Area: Storm-based polygon
Flood severity: None

Counties Jefferson County, OH, Allegheny County, PA, Armstrong County, PA, Beaver County, PA, Butler County, PA, Washington County, PA, Brooke County, WV, Hancock County, WV

The radar

The Pittsburgh radar (KPBZ), 1 km from the middle of the area, began a volume at 03:44 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

Washington/Dulle, VA (KIAD), launched 00:00Z, 3.7 hours before the alert went out and 299 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: 2808 J/kg
Mixed-layer CIN: -24 J/kg
Mixed-layer LCL: 1565 m above ground
0-6 km bulk shear: 15 kt
0-1 km storm-relative helicity: 38 m²/s²
0-3 km storm-relative helicity: 153 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 4.9

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this areal 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 areal flood warning went out at Aug 12, 9:58 PM EDT, 1 hour 45 minutes earlier.

Area forecast discussion, Aug 12, 9:58 PM EDT, 1 hour 45 minutes before

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Hazardous weather outlook, Aug 12, 9:58 PM EDT, 1 hour 45 minutes before

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In the hours before

Local storm report, Aug 12, 10:24 PM EDT, 1 hour 19 minutes before

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Special weather statement, Aug 12, 10:27 PM EDT, 1 hour 16 minutes before

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Local storm report, Aug 12, 10:29 PM EDT, 1 hour 14 minutes before

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Special weather statement, Aug 12, 11:20 PM EDT, 23 minutes before

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Special weather statement, Aug 12, 11:26 PM EDT, 17 minutes before

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Special weather statement, Aug 12, 11:29 PM EDT, 14 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
Aug 12, 8:36 PM EDT	Flash Flood Warning	PBZ	Allegheny, Armstrong, Beaver, Butler, Washington, Westmoreland	3 hr
Aug 12, 8:39 PM EDT	Severe Thunderstorm Warning	PBZ	Allegheny, Beaver, Washington	51 min
Aug 12, 8:58 PM EDT	Severe Thunderstorm Warning	PBZ	Allegheny, Fayette, Indiana, Washington, Westmoreland	41 min
Aug 12, 9:57 PM EDT	Flash Flood Warning	PBZ	Fayette, Washington, Westmoreland	2 hr
Aug 12, 10:10 PM EDT	Special Weather Statement	PBZ	Fayette	35 min
Aug 12, 10:32 PM EDT	Areal Flood Warning	PBZ	Allegheny, Washington, Westmoreland	3 hr
Aug 13, 12:17 AM EDT	Areal Flood Warning	PBZ	Fayette, Washington, Westmoreland	57 min
Aug 13, 5:58 PM EDT	Special Weather Statement	PBZ	Greene	32 min
Aug 13, 6:19 PM EDT	Special Weather Statement	PBZ	Greene, Washington	26 min
Aug 13, 6:29 PM EDT	Special Weather Statement	PBZ	Beaver	31 min
Aug 13, 6:44 PM EDT	Special Weather Statement	PBZ	Beaver	31 min
Aug 13, 6:47 PM EDT	Severe Thunderstorm Warning	PBZ	Allegheny, Beaver, Butler	43 min
Aug 13, 6:50 PM EDT	Special Weather Statement	PBZ	Westmoreland	25 min
Aug 13, 6:56 PM EDT	Severe Thunderstorm Warning	PBZ	Allegheny, Beaver, Washington	49 min
Aug 13, 7:00 PM EDT	Severe Thunderstorm Warning	PBZ	Allegheny, Beaver, Butler, Lawrence	45 min
Aug 13, 7:01 PM EDT	Severe Thunderstorm Warning	PBZ	Allegheny, Beaver, Butler	44 min
Aug 13, 7:02 PM EDT	Severe Thunderstorm Warning	PBZ	Allegheny, Fayette, Washington, Westmoreland	28 min
Aug 13, 7:04 PM EDT	Severe Thunderstorm Warning	PBZ	Allegheny	26 min
Aug 13, 7:12 PM EDT	Special Weather Statement	PBZ	Butler	33 min
Aug 13, 7:21 PM EDT	Severe Thunderstorm Warning	PBZ	Allegheny	39 min
Aug 13, 7:22 PM EDT	Severe Thunderstorm Warning	PBZ	Allegheny, Beaver, Washington	53 min
Aug 13, 7:27 PM EDT	Severe Thunderstorm Warning	PBZ	Armstrong, Butler, Clarion	48 min
Aug 13, 7:29 PM EDT	Severe Thunderstorm Warning	PBZ	Fayette, Westmoreland	46 min
Aug 13, 7:37 PM EDT	Severe Thunderstorm Warning	PBZ	Armstrong, Indiana, Westmoreland	53 min
Aug 13, 7:42 PM EDT	Severe Thunderstorm Warning	PBZ	Allegheny, Armstrong, Westmoreland	48 min
Aug 13, 7:45 PM EDT	Flash Flood Warning	PBZ	Allegheny	104 min
Aug 13, 7:45 PM EDT	Severe Thunderstorm Warning	PBZ	Allegheny, Beaver, Butler, Lawrence	30 min
Aug 13, 7:52 PM EDT	Special Weather Statement	PBZ	Clarion, Forest, Venango	23 min
Aug 12, 10:27 PM EDT	Special Weather Statement	PBZ	Monongalia	48 min
Aug 12, 11:20 PM EDT	Special Weather Statement	PBZ	Preston	25 min
Aug 13, 5:04 PM EDT	Special Weather Statement	PBZ	Wetzel	41 min
Aug 13, 5:39 PM EDT	Special Weather Statement	PBZ	Marshall	36 min
Aug 13, 6:25 PM EDT	Special Weather Statement	PBZ	Hancock	35 min
Aug 13, 6:39 PM EDT	Severe Thunderstorm Warning	PBZ	Brooke, Ohio	27 min
Aug 13, 7:53 PM EDT	Special Weather Statement	PBZ	Tucker	37 min
Aug 12, 9:00 PM EDT	Severe Thunderstorm Warning	PBZ	Carroll, Columbiana, Harrison, Jefferson, Tuscarawas	60 min
Aug 12, 11:26 PM EDT	Special Weather Statement	PBZ	Noble	34 min
Aug 12, 11:29 PM EDT	Special Weather Statement	PBZ	Harrison	46 min
Aug 13, 4:51 PM EDT	Special Weather Statement	PBZ	Muskingum	39 min
Aug 13, 5:07 PM EDT	Special Weather Statement	PBZ	Noble	38 min
Aug 13, 5:13 PM EDT	Severe Thunderstorm Warning	PBZ	Monroe, Noble	47 min
Aug 13, 5:19 PM EDT	Special Weather Statement	PBZ	Columbiana	26 min
Aug 13, 5:24 PM EDT	Severe Thunderstorm Warning	PBZ	Columbiana	39 min
Aug 13, 5:29 PM EDT	Severe Thunderstorm Warning	PBZ	Noble	31 min
Aug 13, 5:36 PM EDT	Special Weather Statement	PBZ	Muskingum	39 min
Aug 13, 5:45 PM EDT	Severe Thunderstorm Warning	PBZ	Guernsey, Muskingum	45 min
Aug 13, 5:56 PM EDT	Severe Thunderstorm Warning	PBZ	Belmont, Guernsey, Noble	34 min
Aug 13, 6:13 PM EDT	Severe Thunderstorm Warning	PBZ	Belmont, Guernsey, Harrison, Jefferson	47 min

Nearby

Areal Flood Warnings in Pennsylvania, 2021 Areal Flood Warnings in West Virginia, 2021 Areal Flood Warnings in Ohio, 2021 Every areal flood warning in 2021

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.