Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 207, NWS State College, PA

August 12, 20214 counties in Pennsylvania

NWS State College, PA issued this severe thunderstorm warning at Aug 12, 2021, 12:51 PM EDT for 4 counties in Pennsylvania. It was in force for 54 min. 3 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 12, 2021, 12:51 PM EDT (16:51 UTC)
Expired: Aug 12, 2021, 1:45 PM EDT
In force: 54 min
Issued by: NWS State College, PA
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

Counties Clinton County, PA, Lycoming County, PA, Potter County, PA, Tioga County, PA

The radar

The State College radar (KCCX), 80 km from the middle of the area, began a volume at 16:50 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 12, 1:15 PM EDT	TSTM WND DMG	2 Ssw English Center, PA	MULTIPLE TREES AND WIRES DOWN.
Aug 12, 1:15 PM EDT	TSTM WND DMG	5 S Morris, PA	TREE DOWN.
Aug 12, 1:25 PM EDT	TSTM WND DMG	6 N Buttonwood, PA	TREES AND WIRES DOWN.

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

The nearest sounding before it

Buffalo Intl Airport, NY (KBUF), launched 12:00Z, 4.9 hours before the alert went out and 188 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: 390 J/kg
Mixed-layer CIN: -48 J/kg
Mixed-layer LCL: 843 m above ground
0-6 km bulk shear: 21 kt
0-1 km storm-relative helicity: 55 m²/s²
0-3 km storm-relative helicity: 87 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

181 
WUUS51 KCTP 121651
SVRCTP
PAC035-081-105-117-121745-
/O.NEW.KCTP.SV.W.0207.210812T1651Z-210812T1745Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service State College PA
1251 PM EDT Thu Aug 12 2021

The National Weather Service in State College PA has issued a

* Severe Thunderstorm Warning for...
  Northwestern Lycoming County in north central Pennsylvania...
  Southeastern Potter County in north central Pennsylvania...
  Southern Tioga County in north central Pennsylvania...
  Northern Clinton County in north central Pennsylvania...

* Until 145 PM EDT.

* At 1251 PM EDT, severe thunderstorms were located along a line
  extending from near Leetonia to near Ole Bull State Park to near
  Kettle Creek State Park, moving east at 40 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Morris, Blossburg, Renovo, South Renovo, Arnot, Cross Fork, Glen
  Union, Waterville, Leonard Harrison State Park, Tamarack, Kettle
  Creek State Park, Cedar Run, Cammal, Ole Bull State Park, Little
  Pine State Park, Westport, Leetonia, Cherry Springs State Park,
  Hyner and Ogdensburg.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4168 7688 4159 7687 4122 7728 4129 7803
      4137 7799 4156 7795 4173 7775
TIME...MOT...LOC 1651Z 280DEG 34KT 4162 7739 4150 7769 4131 7796 

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

$$

Colbert

1 follow-up statement

067 
WWUS51 KCTP 121722
SVSCTP

Severe Weather Statement
National Weather Service State College PA
122 PM EDT Thu Aug 12 2021

PAC105-121731-
/O.CAN.KCTP.SV.W.0207.000000T0000Z-210812T1745Z/
Potter PA-
122 PM EDT Thu Aug 12 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN POTTER COUNTY IS
CANCELLED...

The storms which prompted the warning have moved out of the warned 
area. Therefore, the warning has been cancelled.

A Severe Thunderstorm Watch remains in effect until 800 PM EDT for
north central Pennsylvania.

LAT...LON 4168 7688 4158 7688 4122 7728 4128 7791
      4148 7773 4148 7760 4172 7752
TIME...MOT...LOC 1721Z 277DEG 39KT 4157 7704 4141 7716 4145 7748 4129
7769

$$

PAC035-081-117-121745-
/O.CON.KCTP.SV.W.0207.000000T0000Z-210812T1745Z/
Lycoming PA-Tioga PA-Clinton PA-
122 PM EDT Thu Aug 12 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 145 PM EDT
FOR NORTHWESTERN LYCOMING...SOUTHERN TIOGA AND NORTHERN CLINTON
COUNTIES...

At 121 PM EDT, severe thunderstorms were located along a line
extending from near Ogdensburg to near Trout Run to Slate Run to near
South Renovo, moving east at 45 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
Morris, Blossburg, Renovo, South Renovo, Arnot, Westport, Glen Union,
Leetonia, Waterville, Hyner, Leonard Harrison State Park, Ogdensburg,
Cedar Run, Cammal, Slate Run, English Center, Little Pine State Park,
Buttonwood, Salladasburg and Ski Sawmill Ski Area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4168 7688 4158 7688 4122 7728 4128 7791
      4148 7773 4148 7760 4172 7752
TIME...MOT...LOC 1721Z 277DEG 39KT 4157 7704 4141 7716 4145 7748 4129
7769

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 12, 3:33 AM EDT	Excessive Heat Warning	CTP	Adams, Dauphin, Lancaster, Lebanon, York	39 hr
Aug 12, 3:33 AM EDT	Heat Advisory	CTP	Columbia, Cumberland, Franklin, Fulton, Huntingdon, Juniata and 8 more	39 hr
Aug 12, 12:38 PM EDT	Special Weather Statement	CTP	Tioga	52 min
Aug 12, 1:27 PM EDT	Severe Thunderstorm Warning	CTP	Lycoming, Sullivan	63 min
Aug 12, 1:43 PM EDT	Severe Thunderstorm Warning	CTP	Clearfield	49 min
Aug 12, 1:47 PM EDT	Severe Thunderstorm Warning	CTP	Clinton, Lycoming	58 min
Aug 12, 2:15 PM EDT	Special Weather Statement	CTP	Columbia	30 min
Aug 12, 2:25 PM EDT	Special Weather Statement	CTP	Lycoming	20 min
Aug 12, 2:50 PM EDT	Special Weather Statement	CTP	Columbia, Montour	25 min
Aug 12, 3:19 PM EDT	Special Weather Statement	CTP	Schuylkill	41 min
Aug 12, 5:12 PM EDT	Severe Thunderstorm Warning	CTP	Warren	48 min
Aug 12, 5:27 PM EDT	Special Weather Statement	CTP	Tioga	33 min
Aug 12, 5:46 PM EDT	Severe Thunderstorm Warning	CTP	Clearfield, Elk	44 min
Aug 12, 6:25 PM EDT	Areal Flood Advisory	CTP	Clearfield, Elk	2 hr
Aug 12, 6:25 PM EDT	Severe Thunderstorm Warning	CTP	Clearfield	65 min
Aug 12, 7:07 PM EDT	Severe Thunderstorm Warning	CTP	Clearfield, Elk	53 min
Aug 12, 7:33 PM EDT	Special Weather Statement	CTP	Blair, Cambria	27 min
Aug 12, 7:47 PM EDT	Special Weather Statement	CTP	Centre	28 min
Aug 12, 7:56 PM EDT	Severe Thunderstorm Warning	CTP	Centre, Clearfield	49 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.