Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 257, NWS State College, PA

August 26, 2021Adams County, Pennsylvania

NWS State College, PA issued this severe thunderstorm warning at Aug 26, 2021, 4:41 PM EDT for Adams County, Pennsylvania. It was in force for 34 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 26, 2021, 4:41 PM EDT (20:41 UTC)
Expired
Aug 26, 2021, 5:15 PM EDT
In force
34 min
Issued by
NWS State College, PA
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

County Adams County, PA

The radar

The Sterling radar (KLWX), 109 km from the middle of the area, began a volume at 20:44 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, 8.7 hours before the alert went out and 111 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 12:00Z on 2021-08-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 809 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Washington/Dulle, VA at 12:00Z on 2021-08-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 46 square meters per square second.1939Sfc1 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
809 J/kg
Mixed-layer CIN
-126 J/kg
Mixed-layer LCL
1088 m above ground
0-6 km bulk shear
9 kt
0-1 km storm-relative helicity
46 m²/s²
0-3 km storm-relative helicity
59 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

948 
WUUS51 KCTP 262041
SVRCTP
PAC001-262115-
/O.NEW.KCTP.SV.W.0257.210826T2041Z-210826T2115Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service State College PA
441 PM EDT Thu Aug 26 2021

The National Weather Service in State College PA has issued a

* Severe Thunderstorm Warning for...
  Northwestern Adams County in south central Pennsylvania...

* Until 515 PM EDT.

* At 440 PM EDT, a severe thunderstorm was located north of 
  Cashtown, and is nearly stationary.

  HAZARD...60 mph wind gusts and penny size hail.

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Cashtown, Biglerville, Arendtsville and McKnightstown. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3995 7747 3999 7740 4002 7729 4001 7728
      3986 7723 3986 7746
TIME...MOT...LOC 2040Z 356DEG 3KT 3996 7740 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Travis
1 follow-up statement
475 
WWUS51 KCTP 262108
SVSCTP

Severe Weather Statement
National Weather Service State College PA
508 PM EDT Thu Aug 26 2021

PAC001-262118-
/O.EXP.KCTP.SV.W.0257.000000T0000Z-210826T2115Z/
Adams PA-
508 PM EDT Thu Aug 26 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN ADAMS COUNTY WILL
EXPIRE AT 515 PM EDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire.  However heavy rain
is still possible with this thunderstorm.

LAT...LON 3995 7747 3999 7740 4002 7729 4001 7728
      3986 7723 3986 7746
TIME...MOT...LOC 2108Z 356DEG 3KT 3994 7740 

$$

Travis

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 25, 9:47 PM EDTSpecial Weather StatementCTPFulton43 min
Aug 26, 2:33 PM EDTSpecial Weather StatementCTPSullivan42 min
Aug 26, 3:02 PM EDTSpecial Weather StatementCTPLycoming43 min
Aug 26, 3:53 PM EDTSpecial Weather StatementCTPLycoming37 min
Aug 26, 4:10 PM EDTSpecial Weather StatementCTPLycoming35 min
Aug 26, 4:33 PM EDTSevere Thunderstorm WarningCTPLycoming42 min
Aug 26, 5:34 PM EDTSpecial Weather StatementCTPSomerset26 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2021Every 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.