Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2023

Severe Thunderstorm Warning 96, NWS State College, PA

July 21, 20237 counties in Pennsylvania

NWS State College, PA issued this severe thunderstorm warning at Jul 21, 2023, 1:05 AM EDT for 7 counties in Pennsylvania. It was in force for 40 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, 1:05 AM EDT (05:05 UTC)
Expired
Jul 21, 2023, 1:45 AM EDT
In force
40 min
Issued by
NWS State College, PA
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

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

The radar

The State College radar (KCCX), 117 km from the middle of the area, began a volume at 05:10 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.

IssuedProductOfficeLasted
Jul 20, 6:19 PM EDTSevere Thunderstorm WatchSPC9 hr
Jul 20, 10:28 PM EDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 00:00Z, 5.1 hours before the alert went out and 137 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-pSkew-T log-p diagram, Washington/Dulle, VA at 00:00Z on 2023-07-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 807 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Washington/Dulle, VA at 00:00Z on 2023-07-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 39 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
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 46 minutes earlier.

Area forecast discussion, Jul 20, 11:19 PM EDT, 1 hour 46 minutes before
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Hazardous weather outlook, Jul 21, 12:53 AM EDT, 12 minutes before
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In the hours before

Special weather statement, Jul 20, 11:02 PM EDT, 2 hours 3 minutes before
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Local storm report, Jul 20, 11:17 PM EDT, 1 hour 48 minutes before
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        The site you requested is temporarily down for maintenance or an unexpected outage.
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Local storm report, Jul 20, 11:26 PM EDT, 1 hour 39 minutes before
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        The site you requested is temporarily down for maintenance or an unexpected outage.
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Special weather statement, Jul 21, 12:12 AM EDT, 53 minutes before
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      <h1 id="headline">This service is currently unavailable.</h1>
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        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <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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Local storm report, Jul 21, 12:28 AM EDT, 37 minutes before
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<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <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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Special weather statement, Jul 21, 12:28 AM EDT, 37 minutes before
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<body>
  <main class="wrap">
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      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <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.

IssuedProductOfficeCountiesLasted
Jul 20, 8:39 PM EDTSevere Thunderstorm Warning Considerable damage threatCTPCameron, Clearfield, Elk51 min
Jul 20, 8:53 PM EDTSevere Thunderstorm WarningCTPClinton, Potter67 min
Jul 20, 9:17 PM EDTTornado WarningCTPCameron, Clinton13 min
Jul 20, 9:33 PM EDTSevere Thunderstorm WarningCTPCentre, Clearfield, Clinton42 min
Jul 20, 9:44 PM EDTSevere Thunderstorm WarningCTPClinton, Lycoming, Potter, Tioga46 min
Jul 20, 9:58 PM EDTSpecial Weather StatementCTPBlair, Cambria, Centre47 min
Jul 20, 9:59 PM EDTSevere Thunderstorm WarningCTPClinton, Lycoming61 min
Jul 20, 10:05 PM EDTSevere Thunderstorm WarningCTPBlair, Centre, Huntingdon25 min
Jul 20, 10:25 PM EDTAreal Flood AdvisoryCTPCentre, Clearfield2 hr
Jul 20, 10:31 PM EDTSevere Thunderstorm WarningCTPLycoming, Sullivan, Tioga44 min
Jul 20, 10:37 PM EDTSpecial Weather StatementCTPBlair, Huntingdon, Juniata, Mifflin, Snyder, Union53 min
Jul 20, 10:57 PM EDTSevere Thunderstorm WarningCTPBlair, Huntingdon63 min
Jul 20, 10:58 PM EDTSpecial Weather StatementCTPMontour, Northumberland, Snyder, Union47 min
Jul 20, 11:02 PM EDTSpecial Weather StatementCTPCambria, Somerset58 min
Jul 20, 11:06 PM EDTAreal Flood AdvisoryCTPBlair, Cambria, Huntingdon2 hr
Jul 20, 11:12 PM EDTSevere Thunderstorm WarningCTPColumbia, Lycoming, Montour, Northumberland, Sullivan, Union48 min
Jul 20, 11:46 PM EDTSevere Thunderstorm WarningCTPBedford, Blair, Fulton, Huntingdon, Juniata, Mifflin and 2 more74 min
Jul 21, 12:12 AM EDTSpecial Weather StatementCTPSchuylkill48 min
Jul 21, 12:28 AM EDTSpecial Weather StatementCTPCumberland, Franklin, Fulton, Perry77 min
Jul 21, 12:39 AM EDTSevere Thunderstorm WarningCTPAdams, Cumberland, Franklin, Perry, York51 min
Jul 21, 1:15 AM EDTSpecial Weather StatementCTPSchuylkill30 min
Jul 21, 1:17 AM EDTAreal Flood AdvisoryCTPCumberland, Dauphin, Perry, York118 min
Jul 21, 1:48 AM EDTSevere Thunderstorm WarningCTPDauphin, Lancaster, Lebanon, York72 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2023Every 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.