Alert archive / Pennsylvania / Flash Flood Warnings in 2019

Flash Flood Warning 53, NWS Pittsburgh, PA

July 5, 2019Allegheny County, Pennsylvania

NWS Pittsburgh, PA issued this flash flood warning at Jul 5, 2019, 12:57 PM EDT for Allegheny 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: Jul 5, 2019, 12:57 PM EDT (16:57 UTC)
Expired: Jul 5, 2019, 4:00 PM EDT
In force: 3 hr
Issued by: NWS Pittsburgh, PA
Area: Storm-based polygon
Flood severity: None

County Allegheny County, PA

The radar

The Pittsburgh radar (KPBZ), 21 km from the middle of the area, began a volume at 16:56 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, 5.0 hours before the alert went out and 12 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: 326 J/kg
Mixed-layer CIN: -35 J/kg
Mixed-layer LCL: 1009 m above ground
0-6 km bulk shear: 6 kt
0-1 km storm-relative helicity: 1 m²/s²
0-3 km storm-relative helicity: 32 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 Jul 5, 11:26 AM EDT, 1 hour 31 minutes earlier.

Area forecast discussion, Jul 5, 11:26 AM EDT, 1 hour 31 minutes before

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Hazardous weather outlook, Jul 5, 7:58 AM EDT, 4 hours 59 minutes before

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In the hours before

Local storm report, Jul 5, 11:01 AM EDT, 1 hour 56 minutes before

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  <main class="wrap">
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      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
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The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 4, 8:19 PM EDT	Flash Flood Warning	PBZ	Clarion, Forest, Venango	3 hr
Jul 5, 7:43 AM EDT	Flash Flood Watch	PBZ	Fayette, Westmoreland	14 hr
Jul 5, 12:31 PM EDT	Flash Flood Warning	PBZ	Armstrong, Butler, Clarion	3 hr
Jul 5, 6:06 PM EDT	Flash Flood Warning	PBZ	Mercer	90 min
Jul 5, 5:25 PM EDT	Areal Flood Advisory	PBZ	Monongalia	114 min

Nearby

Flash Flood Warnings in Pennsylvania, 2019 Every flash flood warning in 2019

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.