Alert archive / Pennsylvania / Tornado Warnings in 2021

Tornado Warning 3, NWS Pittsburgh, PA

May 3, 2021Butler County, Lawrence County, Pennsylvania

NWS Pittsburgh, PA issued this tornado warning at May 3, 2021, 9:29 PM EDT for Butler County, Lawrence 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: May 3, 2021, 9:29 PM EDT (01:29 UTC)
Expired: May 3, 2021, 10:00 PM EDT
In force: 31 min
Issued by: NWS Pittsburgh, PA
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 0.75 in

Counties Butler County, PA, Lawrence County, PA

The radar

The Pittsburgh radar (KPBZ), 51 km from the middle of the area, began a volume at 01:30 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
May 3, 9:37 PM EDT	TORNADO	5 Nw Portersville, PA	NWS STORM SURVEY CONCLUDED THAT THRESHOLD WIND DAMAGE TO SEVERAL TREES IN THIS AREA LIKELY RESULTED FROM A BRIEF, WEAK TORNADO.

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

The nearest sounding before it

Pittsburgh, PA (KPIT), launched 00:00Z, 1.5 hours before the alert went out and 66 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: 340 J/kg
Mixed-layer CIN: -5 J/kg
Mixed-layer LCL: 674 m above ground
0-6 km bulk shear: 31 kt
0-1 km storm-relative helicity: 129 m²/s²
0-3 km storm-relative helicity: 151 m²/s²
Significant tornado parameter: 0.2
Supercell composite: 2.1

Open this sounding in Storm Lab

The text

As transmitted.

668 
WFUS51 KPBZ 040129
TORPBZ
PAC019-073-040200-
/O.NEW.KPBZ.TO.W.0003.210504T0129Z-210504T0200Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Pittsburgh PA
929 PM EDT Mon May 3 2021

The National Weather Service in Pittsburgh has issued a

* Tornado Warning for...
  East central Lawrence County in western Pennsylvania...
  West central Butler County in west central Pennsylvania...

* Until 1000 PM EDT.
    
* At 928 PM EDT, a severe thunderstorm capable of producing a tornado
  was located near New Castle, moving east at 20 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 Lawrence and west central Butler Counties, including
  the following locations... Harlansburg, Rose Point Park, Cooper's
  Lake Campground, Plain Grove Township and Moraine State Park.

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 4096 8031 4103 8032 4105 8011 4097 8010
TIME...MOT...LOC 0128Z 263DEG 17KT 4099 8027 

TORNADO...RADAR INDICATED
HAIL...<.75IN

$$

CL

2 follow-up statements

519 
WWUS51 KPBZ 040141
SVSPBZ

Severe Weather Statement
National Weather Service Pittsburgh PA
941 PM EDT Mon May 3 2021

PAC019-073-040200-
/O.CON.KPBZ.TO.W.0003.000000T0000Z-210504T0200Z/
Lawrence PA-Butler PA-
941 PM EDT Mon May 3 2021

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 1000 PM EDT FOR EAST
CENTRAL LAWRENCE AND WEST CENTRAL BUTLER COUNTIES...
    
At 941 PM EDT, a severe thunderstorm capable of producing a tornado
was located 8 miles east of New Castle, moving east at 20 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...
Plain Grove Township...           Harlansburg...
Rose Point Park...                Cooper's Lake Campground...
Moraine State Park...             

This includes Interstate 79 in Pennsylvania between mile markers 101
and 106.
 
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 4096 8024 4104 8025 4105 8011 4097 8010
TIME...MOT...LOC 0141Z 263DEG 17KT 4100 8019 

TORNADO...RADAR INDICATED
HAIL...<.75IN

$$

CL

143 
WWUS51 KPBZ 040154
SVSPBZ

Severe Weather Statement
National Weather Service Pittsburgh PA
954 PM EDT Mon May 3 2021

PAC019-073-040204-
/O.EXP.KPBZ.TO.W.0003.000000T0000Z-210504T0200Z/
Lawrence PA-Butler PA-
954 PM EDT Mon May 3 2021

...THE TORNADO WARNING FOR EAST CENTRAL LAWRENCE AND WEST CENTRAL
BUTLER COUNTIES WILL EXPIRE AT 1000 PM EDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer appears capable of producing a tornado.
Therefore, the warning will be allowed to expire.

LAT...LON 4096 8024 4104 8025 4105 8011 4097 8010
TIME...MOT...LOC 0154Z 263DEG 17KT 4101 8011 

$$

CL

The office that day

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

Issued	Product	Office	Counties	Lasted
May 3, 8:54 PM EDT	Tornado Warning	PBZ	Lawrence	36 min
May 4, 2:56 PM EDT	Tornado Warning	PBZ	Jefferson	19 min
May 4, 6:00 PM EDT	Flash Flood Watch	PBZ	Fayette, Greene	11 hr

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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.