Alert archive / Pennsylvania / Tornado Warnings in 2021

Tornado Warning 16, NWS Pittsburgh, PA

September 22, 2021Armstrong County, Butler County, Pennsylvania

NWS Pittsburgh, PA issued this tornado warning at Sep 22, 2021, 5:43 PM EDT for Armstrong County, Butler County, Pennsylvania. It was in force for 18 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: Sep 22, 2021, 5:43 PM EDT (21:43 UTC)
Expired: Sep 22, 2021, 6:01 PM EDT
In force: 18 min
Issued by: NWS Pittsburgh, PA
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 0.0 in

Counties Armstrong County, PA, Butler County, PA

The radar

The Pittsburgh radar (KPBZ), 54 km from the middle of the area, began a volume at 21:45 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Sep 22, 2:23 PM EDT	Tornado Watch	SPC	6 hr

The nearest sounding before it

Pittsburgh, PA (KPIT), launched 12:00Z, 9.7 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: 155 J/kg
Mixed-layer CIN: -120 J/kg
Mixed-layer LCL: 634 m above ground
0-6 km bulk shear: 36 kt
0-1 km storm-relative helicity: 32 m²/s²
0-3 km storm-relative helicity: 88 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.5

Open this sounding in Storm Lab

The text

As transmitted.

536 
WFUS51 KPBZ 222143
TORPBZ
PAC005-019-222215-
/O.NEW.KPBZ.TO.W.0016.210922T2143Z-210922T2215Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Pittsburgh PA
543 PM EDT Wed Sep 22 2021

The National Weather Service in Pittsburgh has issued a

* Tornado Warning for...
  East central Butler County in west central Pennsylvania...
  Northwestern Armstrong County in west central Pennsylvania...

* Until 615 PM EDT.
    
* At 543 PM EDT, a severe thunderstorm capable of producing a tornado
  was located near Butler, moving northeast at 30 mph.

  HAZARD...Tornado.

  SOURCE...Radar indicated rotation.

  IMPACT...Flying debris will be dangerous to those caught without 
           shelter. Mobile homes will be damaged or destroyed. 
           Damage to roofs, windows, and vehicles will occur.  Tree 
           damage is likely.

* This tornadic thunderstorm will remain over mainly rural areas of
  east central Butler and northwestern Armstrong Counties, including
  the following locations... Chicora, Fairview, East Butler, Hooker,
  Karns City, Bruin and Petrolia.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

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

&&

LAT...LON 4080 7980 4083 7991 4100 7990 4106 7973
      4093 7969
TIME...MOT...LOC 2143Z 205DEG 24KT 4088 7984 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...0.00 IN

$$

2 follow-up statements

910 
WWUS51 KPBZ 222150
SVSPBZ

Severe Weather Statement
National Weather Service Pittsburgh PA
550 PM EDT Wed Sep 22 2021

PAC005-019-222215-
/O.CON.KPBZ.TO.W.0016.000000T0000Z-210922T2215Z/
Butler PA-Armstrong PA-
550 PM EDT Wed Sep 22 2021

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 615 PM EDT FOR EAST
CENTRAL BUTLER AND NORTHWESTERN ARMSTRONG COUNTIES...
    
At 550 PM EDT, a severe thunderstorm capable of producing a tornado
was located near Shanor-Northvue, or near Butler, moving northeast at
30 mph.

HAZARD...Tornado.

SOURCE...Radar indicated rotation.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely.

Locations impacted include...
Homeacre-Lyndora, Shanor-Northvue, Chicora, East Butler, Bruin,
Petrolia, Karns City, Fairview, and Hooker.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

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

&&

LAT...LON 4084 7977 4089 7990 4100 7990 4106 7973
      4093 7969
TIME...MOT...LOC 2150Z 205DEG 24KT 4093 7981 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...0.00 IN

$$

052 
WWUS51 KPBZ 222201
SVSPBZ

Severe Weather Statement
National Weather Service Pittsburgh PA
601 PM EDT Wed Sep 22 2021

PAC005-019-222210-
/O.CAN.KPBZ.TO.W.0016.000000T0000Z-210922T2215Z/
Butler PA-Armstrong PA-
601 PM EDT Wed Sep 22 2021

...THE TORNADO WARNING FOR EAST CENTRAL BUTLER AND NORTHWESTERN
ARMSTRONG COUNTIES IS CANCELLED...
                
The storm which prompted the warning has weakened below severe
limits, and no longer appears capable of producing a tornado.
Therefore, the warning has been cancelled.  However, gusty winds are 
still possible with this thunderstorm.

A Tornado Watch remains in effect until 1000 PM EDT for west central
Pennsylvania.

LAT...LON 4084 7977 4089 7990 4100 7990 4106 7973
      4093 7969
TIME...MOT...LOC 2158Z 205DEG 24KT 4099 7977 

$$

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 22, 4:25 PM EDT	Special Weather Statement	PBZ	Beaver	35 min
Sep 22, 4:53 PM EDT	Special Weather Statement	PBZ	Allegheny, Beaver, Butler	37 min
Sep 22, 5:25 PM EDT	Special Weather Statement	PBZ	Butler	35 min
Sep 22, 6:04 PM EDT	Tornado Warning	PBZ	Butler, Venango	12 min

Nearby

Tornado Warnings in Pennsylvania, 2021 Every tornado warning in 2021 Tornadoes 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.