Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2019

Severe Thunderstorm Warning 204, NWS State College, PA

July 21, 2019York County, Pennsylvania

NWS State College, PA issued this severe thunderstorm warning at Jul 21, 2019, 6:04 PM EDT for York County, Pennsylvania. It was in force for 56 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 21, 2019, 6:04 PM EDT (22:04 UTC)
Expired: Jul 21, 2019, 7:00 PM EDT
In force: 56 min
Issued by: NWS State College, PA
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

County York County, PA

The radar

The Sterling radar (KLWX), 124 km from the middle of the area, began a volume at 22:04 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

Wallops Is Stn, VA (KWAL), launched 12:00Z, 10.1 hours before the alert went out and 249 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: 2169 J/kg
Mixed-layer CIN: -73 J/kg
Mixed-layer LCL: 1337 m above ground
0-6 km bulk shear: 14 kt
0-1 km storm-relative helicity: 21 m²/s²
0-3 km storm-relative helicity: 30 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 State College, PA wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 21, 3:41 PM EDT, 2 hours 23 minutes earlier.

Area forecast discussion, Jul 21, 3:41 PM EDT, 2 hours 23 minutes before

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Hazardous weather outlook, Jul 21, 3:16 PM EDT, 2 hours 48 minutes before

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In the hours before

Special weather statement, Jul 21, 3:19 PM EDT, 2 hours 45 minutes before

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Special weather statement, Jul 21, 3:39 PM EDT, 2 hours 25 minutes before

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Special weather statement, Jul 21, 3:51 PM EDT, 2 hours 13 minutes before

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Special weather statement, Jul 21, 3:51 PM EDT, 2 hours 13 minutes before

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Special weather statement, Jul 21, 4:37 PM EDT, 1 hour 27 minutes before

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Local storm report, Jul 21, 5:53 PM EDT, 11 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 20, 10:39 PM EDT	Special Weather Statement	CTP	Elk	51 min
Jul 21, 3:07 PM EDT	Flash Flood Watch	CTP	Adams, Bedford, Columbia, Cumberland, Dauphin, Franklin and 9 more	35 hr
Jul 21, 3:17 PM EDT	Special Weather Statement	CTP	Somerset	58 min
Jul 21, 3:19 PM EDT	Special Weather Statement	CTP	Sullivan	26 min
Jul 21, 3:39 PM EDT	Special Weather Statement	CTP	Huntingdon	81 min
Jul 21, 3:51 PM EDT	Special Weather Statement	CTP	Bedford	39 min
Jul 21, 4:37 PM EDT	Special Weather Statement	CTP	Fulton	38 min
Jul 21, 5:12 PM EDT	Severe Thunderstorm Warning	CTP	Franklin, Fulton	53 min
Jul 21, 6:00 PM EDT	Severe Thunderstorm Warning	CTP	Centre, Clearfield	25 min
Jul 21, 6:19 PM EDT	Areal Flood Advisory	CTP	Adams, York	3 hr
Jul 21, 7:15 PM EDT	Special Weather Statement	CTP	Somerset	45 min
Jul 21, 7:26 PM EDT	Severe Thunderstorm Warning	CTP	Adams, York	64 min
Jul 21, 7:42 PM EDT	Areal Flood Advisory	CTP	Somerset	3 hr
Jul 21, 7:51 PM EDT	Special Weather Statement	CTP	Schuylkill	54 min

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.