Alert archive / Pennsylvania / Areal Flood Warnings in 2021

Areal Flood Warning 16, NWS Pittsburgh, PA

September 1, 2021Fayette County, Indiana County, Westmoreland County, Pennsylvania

NWS Pittsburgh, PA issued this areal flood warning at Sep 1, 2021, 1:24 PM EDT for Fayette County, Indiana County, Westmoreland County, Pennsylvania. It was in force for 2 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: Sep 1, 2021, 1:24 PM EDT (17:24 UTC)
Expired: Sep 1, 2021, 3:32 PM EDT
In force: 2 hr
Issued by: NWS Pittsburgh, PA
Area: Storm-based polygon
Flood severity: None

Counties Fayette County, PA, Indiana County, PA, Westmoreland County, PA

The radar

The Pittsburgh radar (KPBZ), 74 km from the middle of the area, began a volume at 17:23 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, 5.4 hours before the alert went out and 61 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: 666 m above ground
0-6 km bulk shear: 24 kt
0-1 km storm-relative helicity: -93 m²/s²
0-3 km storm-relative helicity: -7 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 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 Sep 1, 12:07 PM EDT, 1 hour 17 minutes earlier.

Area forecast discussion, Sep 1, 12:07 PM EDT, 1 hour 17 minutes before

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Hazardous weather outlook, Sep 1, 12:04 PM EDT, 1 hour 20 minutes before

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In the hours before

Local storm report, Sep 1, 12:25 PM EDT, 59 minutes before

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Local storm report, Sep 1, 12:26 PM EDT, 58 minutes before

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Local storm report, Sep 1, 12:35 PM EDT, 49 minutes before

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Local storm report, Sep 1, 12:36 PM EDT, 48 minutes before

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Local storm report, Sep 1, 12:48 PM EDT, 36 minutes before

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Local storm report, Sep 1, 12:49 PM EDT, 35 minutes before

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      <p id="message2">
        Please try again in a few minutes.
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      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
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The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 1, 5:05 AM EDT	Areal Flood Advisory	PBZ	Allegheny, Beaver, Fayette, Washington, Westmoreland	104 min
Sep 1, 6:23 AM EDT	Flash Flood Warning	PBZ	Allegheny, Armstrong, Beaver, Butler, Indiana, Washington and 1 more	5 hr
Sep 1, 7:16 AM EDT	Flash Flood Warning	PBZ	Armstrong, Indiana, Westmoreland	6 hr
Sep 1, 7:21 AM EDT	Flash Flood Warning	PBZ	Fayette, Greene	6 hr
Sep 1, 7:50 AM EDT	Flash Flood Warning	PBZ	Washington	3 hr
Sep 1, 9:27 AM EDT	Flash Flood Warning	PBZ	Allegheny, Armstrong, Fayette, Greene, Indiana, Washington and 1 more	4 hr
Sep 1, 10:26 AM EDT	Areal Flood Advisory	PBZ	Washington	109 min
Sep 1, 11:23 AM EDT	Areal Flood Advisory	PBZ	Allegheny, Armstrong, Beaver, Butler, Indiana, Washington and 1 more	52 min
Sep 1, 11:30 AM EDT	River Flood Warning	PBZ	Indiana, Westmoreland	16 hr
Sep 1, 11:30 AM EDT	River Flood Warning	PBZ	Fayette	39 hr
Sep 1, 11:30 AM EDT	River Flood Warning	PBZ	Fayette, Washington, Westmoreland	28 hr
Sep 1, 11:30 AM EDT	River Flood Warning	PBZ	Allegheny, Westmoreland	40 hr
Sep 1, 11:30 AM EDT	River Flood Warning	PBZ	Allegheny, Washington, Westmoreland	33 hr
Sep 1, 1:15 PM EDT	Areal Flood Warning	PBZ	Fayette	2 hr
Sep 1, 1:16 PM EDT	Areal Flood Warning	PBZ	Indiana, Westmoreland	2 hr
Sep 1, 1:02 PM EDT	Areal Flood Warning	PBZ	Noble	31 hr

Nearby

Areal Flood Warnings in Pennsylvania, 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.