Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 183, NWS Pittsburgh, PA

July 20, 20215 counties in Pennsylvania

NWS Pittsburgh, PA issued this severe thunderstorm warning at Jul 20, 2021, 8:32 PM EDT for 5 counties in Pennsylvania. It was in force for 43 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
Jul 20, 2021, 8:32 PM EDT (00:32 UTC)
Expired
Jul 20, 2021, 9:15 PM EDT
In force
43 min
Issued by
NWS Pittsburgh, PA
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Armstrong County, PA, Clarion County, PA, Forest County, PA, Indiana County, PA, Jefferson County, PA

The radar

The State College radar (KCCX), 85 km from the middle of the area, began a volume at 00:33 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

Pittsburgh, PA (KPIT), launched 00:00Z, 0.5 hours before the alert went out and 133 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, Pittsburgh, PA at 00:00Z on 2021-07-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 416 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, Pittsburgh, PA at 00:00Z on 2021-07-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 22 square meters per square second.193958Sfc1 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
416 J/kg
Mixed-layer CIN
-16 J/kg
Mixed-layer LCL
1443 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
22 m²/s²
0-3 km storm-relative helicity
33 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.6

Open this sounding in Storm Lab

The text

As transmitted.

357 
WUUS51 KPBZ 210032
SVRPBZ
PAC005-031-053-063-065-210115-
/O.NEW.KPBZ.SV.W.0183.210721T0032Z-210721T0115Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Pittsburgh PA
832 PM EDT Tue Jul 20 2021

The National Weather Service in Pittsburgh has issued a

* Severe Thunderstorm Warning for...
  Northeastern Indiana County in west central Pennsylvania...
  Jefferson County in west central Pennsylvania...
  East central Armstrong County in west central Pennsylvania...
  Southeastern Clarion County in west central Pennsylvania...
  Southeastern Forest County in northwestern Pennsylvania...

* Until 915 PM EDT.

* At 832 PM EDT, a severe thunderstorm was located over Brookville,
  moving southeast at 35 mph.

  HAZARD...Wind gusts to 60 mph and quarter-size hail.

  SOURCE...Radar.

  IMPACT...Minor hail damage to vehicles is possible. Expect wind 
           damage to trees and power lines, resulting in some power 
           outages.

* Locations impacted include...
  Punxsutawney...                   Clarion...
  Brookville...                     Reynoldsville...
  Brockway...                       New Bethlehem...
  Sykesville...                     Falls Creek...
  Sligo...                          Big Run...
  Dayton...                         Strattanville...

This includes Interstate 80 in Pennsylvania between mile markers 61
and 96.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

This storm has produced damaging wind and large hail. Move indoors
and stay away from windows!

Please report severe weather by calling 412-262-1988, posting to 
the NWS Pittsburgh Facebook page, or using Twitter @NWSPITTSBURGH. 

&&

LAT...LON 4120 7877 4113 7880 4085 7881 4085 7928
      4115 7953 4135 7907 4135 7905 4136 7903
      4135 7902 4138 7897 4136 7896 4126 7874
      4123 7874 4123 7871 4120 7871
TIME...MOT...LOC 0032Z 321DEG 30KT 4114 7908 

HAIL...1.00IN
WIND...60MPH
 
$$
2 follow-up statements
876 
WWUS51 KPBZ 210055
SVSPBZ

Severe Weather Statement
National Weather Service Pittsburgh PA
855 PM EDT Tue Jul 20 2021

PAC005-031-053-063-065-210115-
/O.CON.KPBZ.SV.W.0183.000000T0000Z-210721T0115Z/
Indiana PA-Jefferson PA-Armstrong PA-Clarion PA-Forest PA-
855 PM EDT Tue Jul 20 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 915 PM EDT
FOR NORTHEASTERN INDIANA...JEFFERSON...EAST CENTRAL ARMSTRONG...
SOUTHEASTERN CLARION AND SOUTHEASTERN FOREST COUNTIES...

At 854 PM EDT, a severe thunderstorm was located near Punxsutawney,
and is nearly stationary.

HAZARD...Wind gusts to 60 mph.

SOURCE...Radar.

IMPACT...Expect damage to trees and power lines, resulting in some 
         power outages.

Locations impacted include...
Punxsutawney...                   Clarion...
Brookville...                     Reynoldsville...
Brockway...                       New Bethlehem...
Sykesville...                     Falls Creek...
Sligo...                          Big Run...
Dayton...                         Strattanville...

This includes Interstate 80 in Pennsylvania between mile markers 61
and 96.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

This storm has produced damaging wind and large hail. Move indoors
and stay away from windows!

Please report severe weather by calling 412-262-1988, posting to 
the NWS Pittsburgh Facebook page, or using Twitter @NWSPITTSBURGH. 

&&

LAT...LON 4120 7877 4113 7880 4085 7881 4085 7928
      4115 7953 4135 7907 4135 7905 4136 7903
      4135 7902 4138 7897 4136 7896 4126 7874
      4123 7874 4123 7871 4120 7871
TIME...MOT...LOC 0054Z 321DEG 30KT 4101 7894 

HAIL...<.75IN
WIND...60MPH
 
$$
342 
WWUS51 KPBZ 210105
SVSPBZ

Severe Weather Statement
National Weather Service Pittsburgh PA
905 PM EDT Tue Jul 20 2021

PAC005-031-053-063-065-210115-
/O.EXP.KPBZ.SV.W.0183.000000T0000Z-210721T0115Z/
Indiana PA-Jefferson PA-Armstrong PA-Clarion PA-Forest PA-
905 PM EDT Tue Jul 20 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN INDIANA...
JEFFERSON...EAST CENTRAL ARMSTRONG...SOUTHEASTERN CLARION AND
SOUTHEASTERN FOREST COUNTIES WILL EXPIRE AT 915 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 gusty
winds and heavy rain are still possible with this thunderstorm.

LAT...LON 4120 7877 4113 7880 4085 7881 4085 7928
      4115 7953 4135 7907 4135 7905 4136 7903
      4135 7902 4138 7897 4136 7896 4126 7874
      4123 7874 4123 7871 4120 7871
TIME...MOT...LOC 0105Z 321DEG 30KT 4095 7887 

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 20, 8:31 PM EDTSpecial Weather StatementPBZBeaver29 min
Jul 20, 8:45 PM EDTSevere Thunderstorm WarningPBZAllegheny, Beaver, Butler30 min
Jul 20, 9:11 PM EDTSpecial Weather StatementPBZButler34 min
Jul 20, 9:16 PM EDTSpecial Weather StatementPBZArmstrong29 min
Jul 20, 9:39 PM EDTSpecial Weather StatementPBZArmstrong36 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.