Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 285, NWS Pittsburgh, PA

August 13, 2021Armstrong County, Indiana County, Westmoreland County, Pennsylvania

NWS Pittsburgh, PA issued this severe thunderstorm warning at Aug 13, 2021, 8:11 PM EDT for Armstrong County, Indiana County, Westmoreland County, Pennsylvania. It was in force for 31 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: Aug 13, 2021, 8:11 PM EDT (00:11 UTC)
Expired: Aug 13, 2021, 8:42 PM EDT
In force: 31 min
Issued by: NWS Pittsburgh, PA
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

Counties Armstrong County, PA, Indiana County, PA, Westmoreland County, PA

The radar

The Pittsburgh radar (KPBZ), 63 km from the middle of the area, began a volume at 00:12 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 13, 8:12 PM EDT	TSTM WND DMG	1 Nne Cooks Summit, PA	TREES DOWN AROUND CROOKED CREEK PARK

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 13, 4:46 PM EDT	Severe Thunderstorm Watch	SPC	5 hr

The nearest sounding before it

Pittsburgh, PA (KPIT), launched 00:00Z, 0.2 hours before the alert went out and 60 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: 1815 J/kg
Mixed-layer CIN: -1 J/kg
Mixed-layer LCL: 1196 m above ground
0-6 km bulk shear: 43 kt
0-1 km storm-relative helicity: 73 m²/s²
0-3 km storm-relative helicity: 111 m²/s²
Significant tornado parameter: 0.7
Supercell composite: 5.8

Open this sounding in Storm Lab

The text

As transmitted.

197 
WUUS51 KPBZ 140011
SVRPBZ
PAC005-063-129-140100-
/O.NEW.KPBZ.SV.W.0285.210814T0011Z-210814T0100Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Pittsburgh PA
811 PM EDT Fri Aug 13 2021

The National Weather Service in Pittsburgh has issued a

* Severe Thunderstorm Warning for...
  Northwestern Indiana County in west central Pennsylvania...
  North central Westmoreland County in southwestern Pennsylvania...
  Southern Armstrong County in west central Pennsylvania...

* Until 900 PM EDT.

* At 811 PM EDT, a severe thunderstorm was located over Leechburg, or
  near Vandergrift, moving northeast at 40 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Vandergrift, Apollo, Lower Burrell, Harrison Township, Ford City,
  Leechburg, Freeport, North Apollo, West Leechburg, Orchard Hills,
  Rural Valley, and Oklahoma.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 4066 7913 4053 7965 4061 7972 4064 7969
      4065 7969 4066 7970 4069 7969 4091 7935
      4082 7918
TIME...MOT...LOC 0011Z 242DEG 34KT 4066 7960 

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

$$

RACKLEY

3 follow-up statements

599 
WWUS51 KPBZ 140025
SVSPBZ

Severe Weather Statement
National Weather Service Pittsburgh PA
825 PM EDT Fri Aug 13 2021

PAC129-140034-
/O.CAN.KPBZ.SV.W.0285.000000T0000Z-210814T0100Z/
Westmoreland PA-
825 PM EDT Fri Aug 13 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTH CENTRAL WESTMORELAND
COUNTY IS CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

A Severe Thunderstorm Watch remains in effect until 1100 PM EDT for
west central Pennsylvania.

LAT...LON 4064 7952 4075 7959 4089 7932 4082 7918
      4068 7914 4060 7939
TIME...MOT...LOC 0024Z 243DEG 38KT 4075 7938 

$$

PAC005-063-140100-
/O.CON.KPBZ.SV.W.0285.000000T0000Z-210814T0100Z/
Indiana PA-Armstrong PA-
825 PM EDT Fri Aug 13 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 900 PM EDT
FOR NORTHWESTERN INDIANA AND SOUTHERN ARMSTRONG COUNTIES...

At 824 PM EDT, a severe thunderstorm was located 8 miles east of Ford
City, or 9 miles southeast of Kittanning, moving northeast at 45 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
Ford City, Rural Valley, Ernest, Manorville, Ford Cliff, Elderton,
Creekside, Plumville, Lenape Heights, Shelocta, Atwood, and Crooked
Creek Lake Park.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 4064 7952 4075 7959 4089 7932 4082 7918
      4068 7914 4060 7939
TIME...MOT...LOC 0024Z 243DEG 38KT 4075 7938 

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

$$

RACKLEY

644 
WWUS51 KPBZ 140035
SVSPBZ

Severe Weather Statement
National Weather Service Pittsburgh PA
835 PM EDT Fri Aug 13 2021

PAC005-063-140100-
/O.CON.KPBZ.SV.W.0285.000000T0000Z-210814T0100Z/
Indiana PA-Armstrong PA-
835 PM EDT Fri Aug 13 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 900 PM EDT
FOR NORTH CENTRAL INDIANA AND EAST CENTRAL ARMSTRONG COUNTIES...

At 835 PM EDT, a severe thunderstorm was located 13 miles north of
Indiana, moving northeast at 40 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
Rural Valley, Plumville, and Atwood. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 4074 7938 4081 7942 4088 7930 4082 7918
      4078 7917 4070 7929
TIME...MOT...LOC 0035Z 242DEG 34KT 4080 7925 

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

$$

RACKLEY

395 
WWUS51 KPBZ 140042
SVSPBZ

Severe Weather Statement
National Weather Service Pittsburgh PA
842 PM EDT Fri Aug 13 2021

PAC005-063-140052-
/O.CAN.KPBZ.SV.W.0285.000000T0000Z-210814T0100Z/
Indiana PA-Armstrong PA-
842 PM EDT Fri Aug 13 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTH CENTRAL INDIANA AND EAST
CENTRAL ARMSTRONG COUNTIES IS CANCELLED...
                
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 has been cancelled.  However gusty winds are
still possible with this thunderstorm.

A Severe Thunderstorm Watch remains in effect until 1100 PM EDT for
west central Pennsylvania.

LAT...LON 4074 7938 4081 7942 4088 7930 4082 7918
      4078 7917 4070 7929
TIME...MOT...LOC 0040Z 242DEG 34KT 4083 7917 

$$

RACKLEY

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 13, 8:32 PM EDT	Special Weather Statement	PBZ	Indiana	28 min
Aug 13, 8:41 PM EDT	Special Weather Statement	PBZ	Mercer	34 min
Aug 13, 8:47 PM EDT	Special Weather Statement	PBZ	Venango	28 min
Aug 13, 9:00 PM EDT	Special Weather Statement	PBZ	Venango	30 min
Aug 13, 9:15 PM EDT	Flash Flood Warning	PBZ	Forest, Lawrence, Mercer, Venango	4 hr

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.