Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2023

Severe Thunderstorm Warning 95, NWS State College, PA

July 21, 20235 counties in Pennsylvania

NWS State College, PA issued this severe thunderstorm warning at Jul 21, 2023, 12:39 AM EDT for 5 counties in Pennsylvania. It was in force for 51 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, 2023, 12:39 AM EDT (04:39 UTC)
Expired: Jul 21, 2023, 1:30 AM EDT
In force: 51 min
Issued by: NWS State College, PA
Area: Storm-based polygon
Tornado: Possible
Hail: 0.88 in
Wind: 60.0 mph

Counties Adams County, PA, Cumberland County, PA, Franklin County, PA, Perry County, PA, York County, PA

The radar

The State College radar (KCCX), 116 km from the middle of the area, began a volume at 04:43 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Jul 20, 6:19 PM EDT	Severe Thunderstorm Watch	SPC	9 hr
Jul 20, 10:28 PM EDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 00:00Z, 4.7 hours before the alert went out and 124 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: 807 J/kg
Mixed-layer CIN: -9 J/kg
Mixed-layer LCL: 1518 m above ground
0-6 km bulk shear: 28 kt
0-1 km storm-relative helicity: 39 m²/s²
0-3 km storm-relative helicity: 97 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 1.2

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 20, 11:19 PM EDT, 1 hour 20 minutes earlier.

Area forecast discussion, Jul 20, 11:19 PM EDT, 1 hour 20 minutes before

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Hazardous weather outlook, Jul 21, 12:14 AM EDT, 25 minutes before

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In the hours before

Special weather statement, Jul 20, 11:02 PM EDT, 1 hour 37 minutes before

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Local storm report, Jul 20, 11:17 PM EDT, 1 hour 22 minutes before

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Local storm report, Jul 20, 11:26 PM EDT, 1 hour 13 minutes before

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Special weather statement, Jul 21, 12:12 AM EDT, 27 minutes before

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Local storm report, Jul 21, 12:28 AM EDT, 11 minutes before

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        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
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Special weather statement, Jul 21, 12:28 AM EDT, 11 minutes before

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      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <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 State College, PA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 20, 8:39 PM EDT	Severe Thunderstorm Warning Considerable damage threat	CTP	Cameron, Clearfield, Elk	51 min
Jul 20, 8:53 PM EDT	Severe Thunderstorm Warning	CTP	Clinton, Potter	67 min
Jul 20, 9:17 PM EDT	Tornado Warning	CTP	Cameron, Clinton	13 min
Jul 20, 9:33 PM EDT	Severe Thunderstorm Warning	CTP	Centre, Clearfield, Clinton	42 min
Jul 20, 9:44 PM EDT	Severe Thunderstorm Warning	CTP	Clinton, Lycoming, Potter, Tioga	46 min
Jul 20, 9:58 PM EDT	Special Weather Statement	CTP	Blair, Cambria, Centre	47 min
Jul 20, 9:59 PM EDT	Severe Thunderstorm Warning	CTP	Clinton, Lycoming	61 min
Jul 20, 10:05 PM EDT	Severe Thunderstorm Warning	CTP	Blair, Centre, Huntingdon	25 min
Jul 20, 10:25 PM EDT	Areal Flood Advisory	CTP	Centre, Clearfield	2 hr
Jul 20, 10:31 PM EDT	Severe Thunderstorm Warning	CTP	Lycoming, Sullivan, Tioga	44 min
Jul 20, 10:37 PM EDT	Special Weather Statement	CTP	Blair, Huntingdon, Juniata, Mifflin, Snyder, Union	53 min
Jul 20, 10:57 PM EDT	Severe Thunderstorm Warning	CTP	Blair, Huntingdon	63 min
Jul 20, 10:58 PM EDT	Special Weather Statement	CTP	Montour, Northumberland, Snyder, Union	47 min
Jul 20, 11:02 PM EDT	Special Weather Statement	CTP	Cambria, Somerset	58 min
Jul 20, 11:06 PM EDT	Areal Flood Advisory	CTP	Blair, Cambria, Huntingdon	2 hr
Jul 20, 11:12 PM EDT	Severe Thunderstorm Warning	CTP	Columbia, Lycoming, Montour, Northumberland, Sullivan, Union	48 min
Jul 20, 11:46 PM EDT	Severe Thunderstorm Warning	CTP	Bedford, Blair, Fulton, Huntingdon, Juniata, Mifflin and 2 more	74 min
Jul 21, 12:12 AM EDT	Special Weather Statement	CTP	Schuylkill	48 min
Jul 21, 12:28 AM EDT	Special Weather Statement	CTP	Cumberland, Franklin, Fulton, Perry	77 min
Jul 21, 1:05 AM EDT	Severe Thunderstorm Warning	CTP	Adams, Cumberland, Dauphin, Franklin, Lebanon, Perry and 1 more	40 min
Jul 21, 1:15 AM EDT	Special Weather Statement	CTP	Schuylkill	30 min
Jul 21, 1:17 AM EDT	Areal Flood Advisory	CTP	Cumberland, Dauphin, Perry, York	118 min
Jul 21, 1:48 AM EDT	Severe Thunderstorm Warning	CTP	Dauphin, Lancaster, Lebanon, York	72 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2023 Every severe thunderstorm warning in 2023

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.