Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2020
Severe Thunderstorm Warning 115, NWS State College, PA
NWS State College, PA issued this severe thunderstorm warning at Jul 21, 2020, 6:43 PM EDT for York County, Pennsylvania. It was in force for 32 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, 2020, 6:43 PM EDT (22:43 UTC)
- Expired
- Jul 21, 2020, 7:15 PM EDT
- In force
- 32 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 22:44 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
Washington/Dulle, VA (KIAD), launched 12:00Z, 10.7 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.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 1997 m above ground
- 0-6 km bulk shear
- 24 kt
- 0-1 km storm-relative helicity
- 4 m²/s²
- 0-3 km storm-relative helicity
- 67 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
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, 6:26 PM EDT, 17 minutes earlier.
Area forecast discussion, Jul 21, 6:26 PM EDT, 17 minutes before
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>Service Notice</title>
<link rel="stylesheet" href="index.css">
</head>
<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.
</p>
</section>
</main>
<script src="index.js"></script>
</body>
</html>Hazardous weather outlook, Jul 21, 5:29 AM EDT, 13 hours 14 minutes before
Hazardous Weather Outlook National Weather Service State College PA 529 AM EDT Tue Jul 21 2020 PAZ004>006-220930- Warren-McKean-Potter- 529 AM EDT Tue Jul 21 2020 This Hazardous Weather Outlook is for central Pennsylvania. .DAY ONE...Today and tonight. The probability for widespread hazardous weather is low. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Isolated strong to severe thunderstorms with gusty winds and locally heavy rain are possible Wednesday afternoon. .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected at this time. PAZ010-011-017-024-033-220930- Elk-Cameron-Clearfield-Cambria-Somerset- 529 AM EDT Tue Jul 21 2020 This Hazardous Weather Outlook is for central Pennsylvania. .DAY ONE...Today and tonight. Slow-moving thunderstorms may produce isolated strong gusty winds and flooding this afternoon. Isolated flooding is most likely in areas that can experience rapid runoff from heavy rainfall. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Isolated strong to severe thunderstorms with gusty winds and locally heavy rain are possible Wednesday afternoon. .SPOTTER INFORMATION STATEMENT... Spotters are encouraged to report significant hazardous weather. PAZ012-037-041-042-045-046-051-053-220930- Northern Clinton-Tioga-Northern Lycoming-Sullivan-Southern Clinton- Southern Lycoming-Montour-Columbia- 529 AM EDT Tue Jul 21 2020 This Hazardous Weather Outlook is for central Pennsylvania. .DAY ONE...Today and tonight. The probability for widespread hazardous weather is low. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Scattered severe thunderstorms with damaging winds 60 mph or greater are possible Wednesday afternoon. .SPOTTER INFORMATION STATEMENT... Spotters are encouraged to report significant hazardous weather. PAZ018-019-025>028-034-035-049-050-052-220930- Northern Centre-Southern Centre-Blair-Huntingdon-Mifflin-Juniata- Bedford-Fulton-Union-Snyder-Northumberland- 529 AM EDT Tue Jul 21 2020 This Hazardous Weather Outlook is for central Pennsylvania. .DAY ONE...Today and tonight. Slow-moving thunderstorms may produce gusty winds and localized flooding this afternoon. Localized flooding is most likely in areas that can experience rapid runoff from heavy rainfall. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Scattered severe thunderstorms with damaging winds 60 mph or greater are possible Wednesday afternoon. .SPOTTER INFORMATION STATEMENT... Spotters are encouraged to report significant hazardous weather. PAZ036-056>059-063>066-220930- Franklin-Perry-Dauphin-Schuylkill-Lebanon-Cumberland-Adams-York- Lancaster- 529 AM EDT Tue Jul 21 2020 This Hazardous Weather Outlook is for central Pennsylvania. .DAY ONE...Today and tonight. Slow-moving thunderstorms may produce gusty winds and localized flooding this afternoon. Localized flooding is most likely in areas that can experience rapid runoff from heavy rainfall. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Scattered severe thunderstorms with damaging winds 60 mph or greater are possible Wednesday afternoon. Maximum heat indices around 100 degrees are probable Wednesday afternoon. Isolated strong to severe thunderstorms with gusty winds are possible Thursday afternoon. .SPOTTER INFORMATION STATEMENT... Spotters are encouraged to report significant hazardous weather. MRS
In the hours before
Special weather statement, Jul 21, 4:43 PM EDT, 2 hours before
Special Weather Statement
National Weather Service State College PA
443 PM EDT Tue Jul 21 2020
PAZ035-036-212130-
Fulton PA-Franklin PA-
443 PM EDT Tue Jul 21 2020
...STRONG THUNDERSTORMS WILL AFFECT SOUTHERN FRANKLIN AND FULTON
COUNTIES UNTIL 530 PM EDT...
At 442 PM EDT, Doppler radar indicated strong thunderstorms along a
line extending from near Berkeley Springs to near
Wilson-Conococheague. Movement was northeast at 35 mph.
Additional storms are also moving in from the west. These storms may
strengthen as they move into Fulton and Franklin Counties.
Wind gusts of up to 55 mph and penny size hail are possible.
Locations impacted include...
Chambersburg, Waynesboro, Greencastle, Guilford, St. Thomas,
Fayetteville, Warfordsburg, Wayne Heights, Mont Alto, Mercersburg,
Scotland, McConnellsburg, Harrisonville, Rouzerville, Marion, Fort
Loudon, Big Cove Tannery, Needmore, Locust Grove and Claylick.
LAT...LON 3972 7837 4002 7817 3997 7760 3985 7746
3972 7746
TIME...MOT...LOC 2042Z 228DEG 30KT 3967 7828 3966 7793
DangeloLocal storm report, Jul 21, 5:42 PM EDT, 1 hour 1 minute before
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>Service Notice</title>
<link rel="stylesheet" href="index.css">
</head>
<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.
</p>
</section>
</main>
<script src="index.js"></script>
</body>
</html>Local storm report, Jul 21, 5:55 PM EDT, 48 minutes before
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>Service Notice</title>
<link rel="stylesheet" href="index.css">
</head>
<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.
</p>
</section>
</main>
<script src="index.js"></script>
</body>
</html>Special weather statement, Jul 21, 6:13 PM EDT, 30 minutes before
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>Service Notice</title>
<link rel="stylesheet" href="index.css">
</head>
<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.
</p>
</section>
</main>
<script src="index.js"></script>
</body>
</html>Special weather statement, Jul 21, 6:24 PM EDT, 19 minutes before
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>Service Notice</title>
<link rel="stylesheet" href="index.css">
</head>
<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.
</p>
</section>
</main>
<script src="index.js"></script>
</body>
</html>Local storm report, Jul 21, 6:29 PM EDT, 14 minutes before
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>Service Notice</title>
<link rel="stylesheet" href="index.css">
</head>
<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.
</p>
</section>
</main>
<script src="index.js"></script>
</body>
</html>The office that day
Everything else NWS State College, PA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 21, 12:15 PM EDT | Special Weather Statement | CTP | Somerset | 45 min |
| Jul 21, 12:56 PM EDT | Special Weather Statement | CTP | Cambria | 34 min |
| Jul 21, 1:03 PM EDT | Severe Thunderstorm Warning | CTP | Cambria | 44 min |
| Jul 21, 1:11 PM EDT | Special Weather Statement | CTP | Cambria | 34 min |
| Jul 21, 1:15 PM EDT | Special Weather Statement | CTP | Bedford | 45 min |
| Jul 21, 1:33 PM EDT | Severe Thunderstorm Warning | CTP | Bedford, Fulton | 42 min |
| Jul 21, 1:40 PM EDT | Special Weather Statement | CTP | Blair | 35 min |
| Jul 21, 2:03 PM EDT | Special Weather Statement | CTP | Cambria | 27 min |
| Jul 21, 2:43 PM EDT | Special Weather Statement | CTP | Huntingdon | 32 min |
| Jul 21, 2:59 PM EDT | Areal Flood Advisory | CTP | Bedford, Blair, Cambria, Huntingdon, Somerset | 3 hr |
| Jul 21, 3:18 PM EDT | Severe Thunderstorm Warning | CTP | Bedford, Somerset | 42 min |
| Jul 21, 3:47 PM EDT | Severe Thunderstorm Warning | CTP | Somerset | 43 min |
| Jul 21, 4:03 PM EDT | Special Weather Statement | CTP | Bedford, Somerset | 42 min |
| Jul 21, 4:40 PM EDT | Special Weather Statement | CTP | Bedford | 35 min |
| Jul 21, 4:43 PM EDT | Special Weather Statement | CTP | Franklin, Fulton | 47 min |
| Jul 21, 5:05 PM EDT | Severe Thunderstorm Warning | CTP | Franklin, Fulton | 55 min |
| Jul 21, 5:41 PM EDT | Severe Thunderstorm Warning | CTP | Adams, Cumberland, Franklin | 34 min |
| Jul 21, 6:13 PM EDT | Special Weather Statement | CTP | Cumberland | 32 min |
| Jul 21, 6:24 PM EDT | Special Weather Statement | CTP | York | 21 min |
| Jul 21, 6:36 PM EDT | Areal Flood Advisory | CTP | Adams, York | 54 min |
| Jul 21, 7:28 PM EDT | Areal Flood Advisory | CTP | Adams, York | 2 hr |
Nearby
Severe Thunderstorm Warnings in Pennsylvania, 2020Every severe thunderstorm warning in 2020
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.