Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 57, NWS State College, PA

June 21, 2021York County, Pennsylvania

NWS State College, PA issued this severe thunderstorm warning at Jun 21, 2021, 5:41 PM EDT for York County, Pennsylvania. It was in force for 34 min. 1 report 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: Jun 21, 2021, 5:41 PM EDT (21:41 UTC)
Expired: Jun 21, 2021, 6:15 PM EDT
In force: 34 min
Issued by: NWS State College, PA
Area: Storm-based polygon
Hail: 1.0 in
Wind: 70.0 mph

County York County, PA

The radar

The Sterling radar (KLWX), 124 km from the middle of the area, began a volume at 21:40 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
Jun 21, 5:47 PM EDT	TSTM WND DMG	Windsor, PA	SEVERAL REPORTS OF TREES AND WIRES DOWN IN WINDSOR BOROUGH, INCLUDING MANOR RD, SMITH ROAD, AND WINTERSTOWN RD.

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
Jun 21, 2:20 PM EDT	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 9.7 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.

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: 329 J/kg
Mixed-layer CIN: -164 J/kg
Mixed-layer LCL: 801 m above ground
0-6 km bulk shear: 11 kt
0-1 km storm-relative helicity: 33 m²/s²
0-3 km storm-relative helicity: 40 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

830 
WUUS51 KCTP 212141
SVRCTP
PAC133-212215-
/O.NEW.KCTP.SV.W.0057.210621T2141Z-210621T2215Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service State College PA
541 PM EDT Mon Jun 21 2021

The National Weather Service in State College PA has issued a

* Severe Thunderstorm Warning for...
  York County in south central Pennsylvania...

* Until 615 PM EDT.

* At 541 PM EDT, severe thunderstorms were located along a line
  extending from Weigelstown to near Jacobus to near Codorus, moving
  east at 40 mph.

  HAZARD...70 mph wind gusts and quarter size hail.

  SOURCE...Trained weather spotters.

  IMPACT...Hail damage to vehicles is expected. Expect considerable 
           tree damage. Wind damage is also likely to mobile homes, 
           roofs, and outbuildings.

* Locations impacted include...
  York, Weigelstown, Red Lion, Spry, Dallastown, Shiloh, East York,
  Stonybrook-Wilshire, West York, Shrewsbury, Codorus, Grantley,
  Tyler Run-Queens Gate, Hallam, Emigsville, Wrightsville, Spring
  Grove, Stewartstown, Glen Rock and North York.

This includes Interstate 83 from mile markers 0 to 22.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

This is a DANGEROUS SITUATION. These storms are producing widespread 
wind damage across Adams and western York County. SEEK SHELTER NOW 
inside a sturdy structure and stay away from windows! 
&&

LAT...LON 3984 7687 3996 7692 4005 7654 3995 7648
      3991 7639 3987 7638 3972 7624 3972 7700
TIME...MOT...LOC 2141Z 258DEG 35KT 3996 7683 3986 7675 3977 7687 

HAIL...1.00IN
WIND...70MPH
 
$$

Banghoff

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 20, 8:03 PM EDT	Special Weather Statement	CTP	Juniata	12 min
Jun 20, 8:13 PM EDT	Severe Thunderstorm Warning	CTP	Juniata, Snyder	24 min
Jun 20, 8:29 PM EDT	Special Weather Statement	CTP	Dauphin	16 min
Jun 20, 8:35 PM EDT	Special Weather Statement	CTP	McKean	25 min
Jun 20, 8:47 PM EDT	Special Weather Statement	CTP	Dauphin	13 min
Jun 20, 9:02 PM EDT	Special Weather Statement	CTP	Dauphin	13 min
Jun 20, 9:16 PM EDT	Special Weather Statement	CTP	Schuylkill	14 min
Jun 20, 9:23 PM EDT	Severe Thunderstorm Warning	CTP	Columbia, Northumberland, Schuylkill	50 min
Jun 20, 9:29 PM EDT	Areal Flood Advisory	CTP	Lebanon, Schuylkill	2 hr
Jun 21, 4:18 AM EDT	Special Weather Statement	CTP	Warren	42 min
Jun 21, 2:19 PM EDT	Special Weather Statement	CTP	Warren	41 min
Jun 21, 2:43 PM EDT	Severe Thunderstorm Warning	CTP	McKean, Warren	47 min
Jun 21, 2:55 PM EDT	Special Weather Statement	CTP	McKean	35 min
Jun 21, 3:09 PM EDT	Severe Thunderstorm Warning	CTP	McKean, Potter	21 min
Jun 21, 3:14 PM EDT	Severe Thunderstorm Warning	CTP	McKean	31 min
Jun 21, 3:20 PM EDT	Special Weather Statement	CTP	Clearfield	25 min
Jun 21, 3:26 PM EDT	Severe Thunderstorm Warning	CTP	Cameron, Elk, McKean, Warren	49 min
Jun 21, 3:35 PM EDT	Special Weather Statement	CTP	Centre	25 min
Jun 21, 3:55 PM EDT	Special Weather Statement	CTP	Tioga	35 min
Jun 21, 3:58 PM EDT	Special Weather Statement	CTP	Snyder	32 min
Jun 21, 4:15 PM EDT	Special Weather Statement	CTP	Cameron, Potter	45 min
Jun 21, 4:17 PM EDT	Special Weather Statement	CTP	Cambria	28 min
Jun 21, 4:18 PM EDT	Special Weather Statement	CTP	Sullivan	27 min
Jun 21, 4:18 PM EDT	Special Weather Statement	CTP	Franklin	27 min
Jun 21, 4:21 PM EDT	Special Weather Statement	CTP	Union	24 min
Jun 21, 4:24 PM EDT	Special Weather Statement	CTP	Centre	21 min
Jun 21, 4:28 PM EDT	Severe Thunderstorm Warning	CTP	Cambria	47 min
Jun 21, 4:31 PM EDT	Special Weather Statement	CTP	Lycoming	44 min
Jun 21, 4:31 PM EDT	Severe Thunderstorm Warning	CTP	Adams, Franklin	59 min
Jun 21, 4:39 PM EDT	Severe Thunderstorm Warning	CTP	Cambria, Somerset	36 min
Jun 21, 4:43 PM EDT	Severe Thunderstorm Warning	CTP	Centre	32 min
Jun 21, 4:45 PM EDT	Severe Thunderstorm Warning	CTP	Lycoming, Sullivan, Tioga	30 min
Jun 21, 4:52 PM EDT	Special Weather Statement	CTP	Clinton	23 min
Jun 21, 4:55 PM EDT	Special Weather Statement	CTP	Blair	20 min
Jun 21, 4:56 PM EDT	Special Weather Statement	CTP	Sullivan	19 min
Jun 21, 5:05 PM EDT	Severe Thunderstorm Warning	CTP	Adams, Cumberland, York	40 min
Jun 21, 5:08 PM EDT	Severe Thunderstorm Warning	CTP	Centre, Clinton, Lycoming	37 min
Jun 21, 5:13 PM EDT	Special Weather Statement	CTP	Bedford, Blair	32 min
Jun 21, 5:31 PM EDT	Severe Thunderstorm Warning	CTP	Lycoming, Sullivan, Tioga	44 min
Jun 21, 5:45 PM EDT	Special Weather Statement	CTP	Montour	45 min
Jun 21, 5:52 PM EDT	Special Weather Statement	CTP	Columbia, Northumberland	23 min
Jun 21, 5:58 PM EDT	Severe Thunderstorm Warning	CTP	Lancaster	47 min
Jun 21, 6:02 PM EDT	Special Weather Statement	CTP	Dauphin	28 min
Jun 21, 6:08 PM EDT	Special Weather Statement	CTP	Sullivan	37 min
Jun 21, 6:15 PM EDT	Severe Thunderstorm Warning	CTP	Sullivan	15 min
Jun 21, 6:20 PM EDT	Special Weather Statement	CTP	Schuylkill	25 min
Jun 21, 6:23 PM EDT	Special Weather Statement	CTP	Schuylkill	37 min
Jun 21, 6:49 PM EDT	Special Weather Statement	CTP	Schuylkill	26 min
Jun 21, 7:00 PM EDT	Special Weather Statement	CTP	Somerset	15 min
Jun 21, 7:12 PM EDT	Special Weather Statement	CTP	Carbon	18 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.