Alert archive / Pennsylvania / Tornado Warnings in 2021

Tornado Warning 8, NWS Pittsburgh, PA

July 11, 2021Jefferson County, Pennsylvania

NWS Pittsburgh, PA issued this tornado warning at Jul 11, 2021, 4:41 PM EDT for Jefferson County, Pennsylvania. It was in force for 14 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 11, 2021, 4:41 PM EDT (20:41 UTC)
Expired
Jul 11, 2021, 4:55 PM EDT
In force
14 min
Issued by
NWS Pittsburgh, PA
Area
Storm-based polygon
Tornado
Radar indicated
Hail
0.75 in

County Jefferson County, PA

The radar

The State College radar (KCCX), 72 km from the middle of the area, began a volume at 20:43 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.

IssuedProductOfficeLasted
Jul 11, 2:40 PM EDTSevere Thunderstorm WatchSPC8 hr

The nearest sounding before it

Pittsburgh, PA (KPIT), launched 12:00Z, 8.7 hours before the alert went out and 142 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 12:00Z on 2021-07-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 5 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 12:00Z on 2021-07-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 90 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
5 J/kg
Mixed-layer CIN
-180 J/kg
Mixed-layer LCL
979 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
90 m²/s²
0-3 km storm-relative helicity
135 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

881 
WFUS51 KPBZ 112041
TORPBZ
PAC065-112115-
/O.NEW.KPBZ.TO.W.0008.210711T2041Z-210711T2115Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Pittsburgh PA
441 PM EDT Sun Jul 11 2021

The National Weather Service in Pittsburgh has issued a

* Tornado Warning for...
  East central Jefferson County in west central Pennsylvania...

* Until 515 PM EDT.
    
* At 441 PM EDT, a severe thunderstorm capable of producing a tornado
  was located near Brockway, or near DuBois, moving east at 25 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 dangerous storm will be near...
  Brockway around 450 PM EDT.

Other locations impacted by this tornadic thunderstorm include Falls
Creek.

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 4120 7877 4114 7880 4115 7886 4120 7892
      4127 7876 4126 7874 4123 7874 4123 7871
      4120 7871
TIME...MOT...LOC 2041Z 252DEG 20KT 4119 7883 

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

$$

Brown
2 follow-up statements
467 
WWUS51 KPBZ 112048
SVSPBZ

Severe Weather Statement
National Weather Service Pittsburgh PA
448 PM EDT Sun Jul 11 2021

PAC065-112115-
/O.CON.KPBZ.TO.W.0008.000000T0000Z-210711T2115Z/
Jefferson PA-
448 PM EDT Sun Jul 11 2021

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 515 PM EDT FOR EAST
CENTRAL JEFFERSON COUNTY...
    
At 447 PM EDT, a severe thunderstorm capable of producing a tornado
was located near Brockway, or near DuBois, moving east at 25 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 Jefferson County.

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 4118 7878 4118 7879 4123 7882 4127 7875
      4126 7874 4123 7874 4123 7871 4120 7871
      4120 7877
TIME...MOT...LOC 2047Z 252DEG 20KT 4120 7878 

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

$$

Brown
004 
WWUS51 KPBZ 112055
SVSPBZ

Severe Weather Statement
National Weather Service Pittsburgh PA
455 PM EDT Sun Jul 11 2021

PAC065-112104-
/O.CAN.KPBZ.TO.W.0008.000000T0000Z-210711T2115Z/
Jefferson PA-
455 PM EDT Sun Jul 11 2021

...THE TORNADO WARNING FOR EAST CENTRAL JEFFERSON COUNTY IS
CANCELLED...
        
The storm which prompted the warning has moved out of the area.
Therefore, the warning has been cancelled.

A Severe Thunderstorm Watch remains in effect until 900 PM EDT for
west central Pennsylvania.

LAT...LON 4118 7878 4118 7879 4123 7882 4127 7875
      4126 7874 4123 7874 4123 7871 4120 7871
      4120 7877
TIME...MOT...LOC 2053Z 252DEG 20KT 4121 7872 

$$

Brown

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 11, 3:31 PM EDTSpecial Weather StatementPBZArmstrong29 min
Jul 11, 5:11 PM EDTSevere Thunderstorm WarningPBZIndiana, Westmoreland34 min

Nearby

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