Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 200, NWS State College, PA

August 11, 2021Dauphin County, Pennsylvania

NWS State College, PA issued this severe thunderstorm warning at Aug 11, 2021, 4:37 PM EDT for Dauphin County, Pennsylvania. It was in force for 53 min. 4 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Aug 11, 2021, 4:37 PM EDT (20:37 UTC)
Expired: Aug 11, 2021, 5:30 PM EDT
In force: 53 min
Issued by: NWS State College, PA
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

County Dauphin County, PA

The radar

The State College radar (KCCX), 121 km from the middle of the area, began a volume at 20:37 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.

What was reported inside it

Time	Report	Where	Remark
Aug 11, 4:46 PM EDT	TSTM WND DMG	2 Nw Skyline View, PA	TREE ACROSS ROAD.
Aug 11, 4:48 PM EDT	TSTM WND DMG	Linglestown, PA	TREE DOWN. REPORTED VIA TWITTER.
Aug 11, 4:52 PM EDT	TSTM WND DMG	1 Wnw Colonial Park, PA	TREE ON A HOUSE.
Aug 11, 5:00 PM EDT	TSTM WND DMG	3 Se Penn National Race, PA	TREES ACROSS ROAD.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The watch it was issued in

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

Issued	Product	Office	Lasted
Aug 11, 3:02 PM EDT	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 8.6 hours before the alert went out and 158 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: 553 J/kg
Mixed-layer CIN: -190 J/kg
Mixed-layer LCL: 1301 m above ground
0-6 km bulk shear: 13 kt
0-1 km storm-relative helicity: 20 m²/s²
0-3 km storm-relative helicity: 77 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

478 
WUUS51 KCTP 112037
SVRCTP
PAC043-112130-
/O.NEW.KCTP.SV.W.0200.210811T2037Z-210811T2130Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service State College PA
437 PM EDT Wed Aug 11 2021

The National Weather Service in State College PA has issued a

* Severe Thunderstorm Warning for...
  Southern Dauphin County in south central Pennsylvania...

* Until 530 PM EDT.

* At 437 PM EDT, a severe thunderstorm was located over Linglestown,
  moving east at 20 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...Expect damage to roofs, siding, and trees.

* Locations impacted include...
  Harrisburg, Hershey, Colonial Park, Progress, Palmyra, Linglestown,
  Steelton, Hummelstown, Paxtonia, Rutherford, Skyline View, Lawnton,
  Campbelltown, Bressler-Enhaut-Oberlin, Penbrook, Paxtang,
  Rockville, Penn National Race Course, Fort Indiantown Gap and
  Dauphin.

This includes the following Interstates...
 Interstate 81 from mile markers 66 to 81.
 Interstate 83 from mile markers 43 to 50.
 Interstate 283 near mile marker 2.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Very heavy rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4024 7687 4026 7690 4029 7692 4031 7692
      4032 7691 4034 7692 4039 7692 4044 7666
      4024 7658 4023 7659
TIME...MOT...LOC 2037Z 265DEG 15KT 4033 7682 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Colbert

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 11, 12:18 AM EDT	Special Weather Statement	CTP	Union	27 min
Aug 11, 3:38 AM EDT	Excessive Heat Warning	CTP	Adams, Columbia, Cumberland, Dauphin, Franklin, Juniata and 10 more	39 hr
Aug 11, 5:03 AM EDT	Special Weather Statement	CTP	Warren	27 min
Aug 11, 6:40 AM EDT	Special Weather Statement	CTP	McKean	50 min
Aug 11, 2:11 PM EDT	Special Weather Statement	CTP	Cambria	49 min
Aug 11, 2:32 PM EDT	Severe Thunderstorm Warning	CTP	Dauphin, Lancaster, Lebanon, York	58 min
Aug 11, 2:59 PM EDT	Special Weather Statement	CTP	Somerset	61 min
Aug 11, 3:02 PM EDT	Special Weather Statement	CTP	Blair	28 min
Aug 11, 3:13 PM EDT	Severe Thunderstorm Warning	CTP	Bedford, Blair, Huntingdon	46 min
Aug 11, 3:28 PM EDT	Severe Thunderstorm Warning	CTP	Centre, Huntingdon, Mifflin	62 min
Aug 11, 3:34 PM EDT	Severe Thunderstorm Warning	CTP	Mifflin	41 min
Aug 11, 3:35 PM EDT	Special Weather Statement	CTP	Huntingdon	25 min
Aug 11, 3:49 PM EDT	Special Weather Statement	CTP	Juniata	26 min
Aug 11, 3:55 PM EDT	Special Weather Statement	CTP	Dauphin	35 min
Aug 11, 4:07 PM EDT	Special Weather Statement	CTP	York	38 min
Aug 11, 4:08 PM EDT	Special Weather Statement	CTP	Franklin	37 min
Aug 11, 4:13 PM EDT	Special Weather Statement	CTP	Juniata, Perry, Snyder, Union	32 min
Aug 11, 4:23 PM EDT	Severe Thunderstorm Warning	CTP	Centre, Snyder, Union	59 min
Aug 11, 4:42 PM EDT	Special Weather Statement	CTP	York	33 min
Aug 11, 4:43 PM EDT	Special Weather Statement	CTP	Cumberland	32 min
Aug 11, 4:47 PM EDT	Severe Thunderstorm Warning	CTP	Dauphin, Juniata, Northumberland, Perry, Snyder	53 min
Aug 11, 4:52 PM EDT	Areal Flood Advisory	CTP	Dauphin	2 hr
Aug 11, 4:54 PM EDT	Special Weather Statement	CTP	Lebanon	36 min
Aug 11, 5:00 PM EDT	Flash Flood Warning Considerable damage threat	CTP	Cumberland, Dauphin, York	85 min
Aug 11, 5:00 PM EDT	Special Weather Statement	CTP	York	30 min
Aug 11, 5:08 PM EDT	Severe Thunderstorm Warning	CTP	Columbia, Montour, Northumberland	52 min
Aug 11, 5:14 PM EDT	Severe Thunderstorm Warning	CTP	Lancaster	46 min
Aug 11, 5:35 PM EDT	Severe Thunderstorm Warning	CTP	Columbia, Northumberland	48 min
Aug 11, 5:44 PM EDT	Areal Flood Advisory	CTP	Lancaster, Lebanon	2 hr
Aug 11, 5:47 PM EDT	Special Weather Statement	CTP	Lancaster, York	58 min
Aug 11, 5:54 PM EDT	Severe Thunderstorm Warning	CTP	Lancaster, York	51 min
Aug 11, 5:58 PM EDT	Severe Thunderstorm Warning	CTP	Lancaster	47 min
Aug 11, 6:25 PM EDT	Areal Flood Advisory	CTP	Cumberland, Dauphin, York	95 min
Aug 11, 7:14 PM EDT	Special Weather Statement	CTP	Warren	31 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2021 Every severe thunderstorm warning in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.