Alert archive / Pennsylvania / Tornado Warnings in 2018

Tornado Warning 7, NWS Pittsburgh, PA

August 21, 2018Jefferson County, Pennsylvania

NWS Pittsburgh, PA issued this tornado warning at Aug 21, 2018, 8:02 PM EDT for Jefferson County, Pennsylvania. It was in force for 28 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
Aug 21, 2018, 8:02 PM EDT (00:02 UTC)
Expired
Aug 21, 2018, 8:30 PM EDT
In force
28 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), 73 km from the middle of the area, began a volume at 00:05 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
Aug 21, 2:41 PM EDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Pittsburgh, PA (KAGC), launched 00:00Z, 0.0 hours before the alert went out and 139 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 2018-08-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 154 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 2018-08-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 106 square meters per square second.1939Sfc1 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
154 J/kg
Mixed-layer CIN
-48 J/kg
Mixed-layer LCL
993 m above ground
0-6 km bulk shear
26 kt
0-1 km storm-relative helicity
106 m²/s²
0-3 km storm-relative helicity
121 m²/s²
Significant tornado parameter
0.1
Supercell composite
1.7

Open this sounding in Storm Lab

The text

As transmitted.

146 
WFUS51 KPBZ 220002
TORPBZ
PAC065-220030-
/O.NEW.KPBZ.TO.W.0007.180822T0002Z-180822T0030Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Pittsburgh PA
802 PM EDT TUE AUG 21 2018

The National Weather Service in Pittsburgh has issued a

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

* Until 830 PM EDT..

* At 801 PM EDT, a severe thunderstorm capable of producing a tornado
  was located over Reynoldsville, or 8 miles east of Brookville,
  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...
  Reynoldsville around 805 PM EDT.
  Brockway around 825 PM EDT.

Other locations impacted by this tornadic thunderstorm include Falls
Creek and Sykesville.

This includes  Interstate 80 in Pennsylvania between mile markers 83
and 96.
 
Please report severe weather by calling 412-262-1988, posting to 
the NWS Pittsburgh Facebook page, or using Twitter @NWSPITTSBURGH. 

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.

&&

LAT...LON 4120 7877 4113 7880 4105 7881 4105 7900
      4117 7902 4127 7875 4126 7874 4123 7874
      4123 7871 4120 7871
TIME...MOT...LOC 0001Z 253DEG 22KT 4112 7893 

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

$$

07
2 follow-up statements
660 
WWUS51 KPBZ 220009
SVSPBZ

Severe Weather Statement
National Weather Service Pittsburgh PA
809 PM EDT TUE AUG 21 2018

PAC065-220030-
/O.CON.KPBZ.TO.W.0007.000000T0000Z-180822T0030Z/
Jefferson PA-
809 PM EDT TUE AUG 21 2018

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 830 PM EDT FOR EAST
CENTRAL JEFFERSON COUNTY...
    
At 809 PM EDT, a severe thunderstorm capable of producing a tornado
was located over Reynoldsville, 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 825 PM EDT.

Other locations impacted by this tornadic thunderstorm include Falls
Creek and Sykesville.

This includes  Interstate 80 in Pennsylvania between mile markers 87
and 96.
 
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 4113 7880 4105 7881 4106 7897
      4118 7896 4127 7875 4126 7874 4123 7874
      4123 7871 4120 7871
TIME...MOT...LOC 0009Z 253DEG 22KT 4114 7886 

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

$$

07
090 
WWUS51 KPBZ 220021
SVSPBZ

Severe Weather Statement
National Weather Service Pittsburgh PA
821 PM EDT TUE AUG 21 2018

PAC065-220030-
/O.EXP.KPBZ.TO.W.0007.000000T0000Z-180822T0030Z/
Jefferson PA-
821 PM EDT TUE AUG 21 2018

...THE TORNADO WARNING FOR EAST CENTRAL JEFFERSON COUNTY WILL EXPIRE
AT 830 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 4120 7877 4113 7880 4105 7881 4106 7897
      4118 7896 4127 7875 4126 7874 4123 7874
      4123 7871 4120 7871
TIME...MOT...LOC 0020Z 253DEG 22KT 4116 7878 

$$

07

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 21, 10:37 PM EDTAreal Flood AdvisoryPBZJefferson2 hr

Nearby

Tornado Warnings in Pennsylvania, 2018Every tornado warning in 2018Tornadoes in 2018

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.