Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2019

Severe Thunderstorm Warning 207, NWS Pittsburgh, PA

July 20, 2019Clarion County, Forest County, Jefferson County, Pennsylvania

NWS Pittsburgh, PA issued this severe thunderstorm warning at Jul 20, 2019, 10:25 PM EDT for Clarion County, Forest County, Jefferson County, Pennsylvania. It was in force for 39 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: Jul 20, 2019, 10:25 PM EDT (02:25 UTC)
Expired: Jul 20, 2019, 11:04 PM EDT
In force: 39 min
Issued by: NWS Pittsburgh, PA
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

Counties Clarion County, PA, Forest County, PA, Jefferson County, PA

The radar

The State College radar (KCCX), 109 km from the middle of the area, began a volume at 02:26 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, 2.4 hours before the alert went out and 122 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: 2715 J/kg
Mixed-layer CIN: -5 J/kg
Mixed-layer LCL: 1135 m above ground
0-6 km bulk shear: 11 kt
0-1 km storm-relative helicity: 29 m²/s²
0-3 km storm-relative helicity: 27 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 severe thunderstorm 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 severe thunderstorm warning went out at Jul 20, 9:27 PM EDT, 58 minutes earlier.

Area forecast discussion, Jul 20, 9:27 PM EDT, 58 minutes before

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Hazardous weather outlook, Jul 20, 9:20 PM EDT, 1 hour 5 minutes before

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In the hours before

Special weather statement, Jul 20, 7:11 PM EDT, 3 hours 14 minutes before

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Special weather statement, Jul 20, 7:24 PM EDT, 3 hours 1 minute before

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Special weather statement, Jul 20, 8:05 PM EDT, 2 hours 20 minutes before

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Special weather statement, Jul 20, 9:51 PM EDT, 34 minutes before

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Special weather statement, Jul 20, 10:20 PM EDT, 5 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
Jul 20, 8:05 PM EDT	Special Weather Statement	PBZ	Venango	40 min
Jul 20, 9:51 PM EDT	Special Weather Statement	PBZ	Clarion, Venango	39 min
Jul 20, 9:56 PM EDT	Severe Thunderstorm Warning	PBZ	Clarion, Forest, Venango	49 min
Jul 20, 10:20 PM EDT	Special Weather Statement	PBZ	Clarion	25 min
Jul 20, 10:50 PM EDT	Special Weather Statement	PBZ	Jefferson	25 min
Jul 21, 1:58 PM EDT	Severe Thunderstorm Warning	PBZ	Allegheny, Beaver, Washington	17 min
Jul 21, 2:17 PM EDT	Severe Thunderstorm Warning	PBZ	Allegheny	28 min
Jul 21, 4:19 PM EDT	Severe Thunderstorm Warning	PBZ	Armstrong, Butler	26 min
Jul 21, 6:14 PM EDT	Severe Thunderstorm Warning	PBZ	Mercer	31 min
Jul 21, 6:54 PM EDT	Severe Thunderstorm Warning	PBZ	Fayette	36 min
Jul 21, 7:29 PM EDT	Flash Flood Warning	PBZ	Fayette	3 hr

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2019 Every severe thunderstorm 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.