Alert archive / Pennsylvania / Tornado Warnings in 2015

Tornado Warning 4, NWS State College, PA

April 20, 2015Dauphin County, Lebanon County, Pennsylvania

NWS State College, PA issued this tornado warning at Apr 20, 2015, 8:43 PM EDT for Dauphin County, Lebanon County, Pennsylvania. It was in force for 32 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
Apr 20, 2015, 8:43 PM EDT (00:43 UTC)
Expired
Apr 20, 2015, 9:15 PM EDT
In force
32 min
Issued by
NWS State College, PA
Area
Storm-based polygon

Counties Dauphin County, PA, Lebanon County, PA

The radar

The State College radar (KCCX), 131 km from the middle of the area, began a volume at 00:42 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
Apr 20, 3:08 PM EDTTornado WatchSPC9 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 00:00Z, 0.7 hours before the alert went out and 175 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, Washington/Dulle, VA at 00:00Z on 2015-04-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 460 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, Washington/Dulle, VA at 00:00Z on 2015-04-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 176 square meters per square second.1939587897117Sfc1 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
460 J/kg
Mixed-layer CIN
-29 J/kg
Mixed-layer LCL
1835 m above ground
0-6 km bulk shear
47 kt
0-1 km storm-relative helicity
176 m²/s²
0-3 km storm-relative helicity
177 m²/s²
Significant tornado parameter
0.1
Supercell composite
3.2

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

537 
WFUS51 KCTP 210043
TORCTP
PAC043-075-210115-
/O.NEW.KCTP.TO.W.0004.150421T0043Z-150421T0115Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE STATE COLLEGE PA
843 PM EDT MON APR 20 2015

THE NATIONAL WEATHER SERVICE IN STATE COLLEGE PA HAS ISSUED A

* TORNADO WARNING FOR...
  EAST CENTRAL DAUPHIN COUNTY IN SOUTH CENTRAL PENNSYLVANIA...
  NORTHWESTERN LEBANON COUNTY IN SOUTH CENTRAL PENNSYLVANIA...

* UNTIL 915 PM EDT
    
* AT 843 PM EDT...DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM
  CAPABLE OF PRODUCING A TORNADO. THIS DANGEROUS STORM WAS LOCATED
  OVER PENN NATIONAL RACE COURSE...AND MOVING NORTHEAST AT 25 MPH.

* LOCATIONS IMPACTED INCLUDE...
  SKYLINE VIEW...FREDERICKSBURG...LICKDALE...FORT INDIANTOWN GAP...
  HARPER TAVERN...PENN NATIONAL RACE COURSE...JONESTOWN AND ONO.

THIS INCLUDES THE FOLLOWING INTERSTATES...
 INTERSTATE 78 FROM MILE MARKERS 0 TO 8.
 INTERSTATE 81 FROM MILE MARKERS 77 TO 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 IN A MOBILE
HOME OR OUTDOORS...MOVE TO THE CLOSEST SUBSTANTIAL SHELTER AND
PROTECT YOURSELF FROM FLYING DEBRIS.

TORNADOES ARE EXTREMELY DIFFICULT TO SEE AND CONFIRM AT NIGHT. DO NOT
WAIT TO SEE OR HEAR THE TORNADO. TAKE COVER NOW.

&&

LAT...LON 4032 7670 4038 7676 4054 7652 4044 7635
TIME...MOT...LOC 0043Z 245DEG 22KT 4038 7668 

$$

LAMBERT
1 follow-up statement
401 
WWUS51 KCTP 210103
SVSCTP

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE STATE COLLEGE PA
903 PM EDT MON APR 20 2015

PAC043-210112-
/O.CAN.KCTP.TO.W.0004.000000T0000Z-150421T0115Z/
DAUPHIN PA-

903 PM EDT MON APR 20 2015

...THE TORNADO WARNING FOR EAST CENTRAL DAUPHIN COUNTY IS
CANCELLED...
    
THE TORNADIC THUNDERSTORM WHICH PROMPTED THE WARNING HAS MOVED OUT 
OF THE WARNED AREA. THEREFORE THE WARNING HAS BEEN CANCELLED.

LAT...LON 4036 7658 4046 7665 4054 7652 4044 7635
TIME...MOT...LOC 0102Z 244DEG 24KT 4045 7654 

$$

PAC075-210115-
/O.CON.KCTP.TO.W.0004.000000T0000Z-150421T0115Z/
LEBANON PA-
903 PM EDT MON APR 20 2015

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 915 PM EDT FOR
NORTHWESTERN LEBANON COUNTY...
    
AT 902 PM EDT...DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM CAPABLE
OF PRODUCING A TORNADO. THIS DANGEROUS STORM WAS LOCATED OVER
LICKDALE...MOVING NORTHEAST AT 25 MPH.

LOCATIONS IMPACTED INCLUDE...
FREDERICKSBURG...LICKDALE...HARPER TAVERN...FORT INDIANTOWN GAP...
JONESTOWN AND ONO.

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 IN A MOBILE
HOME OR OUTDOORS...MOVE TO THE CLOSEST SUBSTANTIAL SHELTER AND
PROTECT YOURSELF FROM FLYING DEBRIS.

TORNADOES ARE EXTREMELY DIFFICULT TO SEE AND CONFIRM AT NIGHT. DO NOT
WAIT TO SEE OR HEAR THE TORNADO. TAKE COVER NOW.

&&

LAT...LON 4036 7658 4046 7665 4054 7652 4044 7635
TIME...MOT...LOC 0102Z 244DEG 24KT 4045 7654 

$$

LAMBERT

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 20, 8:08 PM EDTAreal Flood AdvisoryCTPBlair, Centre, Huntingdon3 hr
Apr 20, 8:10 PM EDTTornado WarningCTPCumberland, Dauphin35 min
Apr 20, 8:19 PM EDTSevere Thunderstorm WarningCTPCentre, Clinton, Huntingdon, Lycoming, Mifflin, Snyder and 1 more56 min
Apr 20, 8:29 PM EDTAreal Flood AdvisoryCTPCumberland, Franklin, Perry3 hr
Apr 20, 8:30 PM EDTSevere Thunderstorm WarningCTPAdams, Cumberland, Franklin60 min
Apr 20, 8:47 PM EDTSevere Thunderstorm WarningCTPLycoming, Sullivan58 min
Apr 20, 8:54 PM EDTSevere Thunderstorm WarningCTPCumberland, Dauphin, Juniata, Lebanon, Northumberland, Perry and 2 more66 min
Apr 20, 9:00 PM EDTSevere Thunderstorm WarningCTPDauphin, Lebanon, Schuylkill60 min
Apr 20, 9:39 PM EDTSpecial Weather StatementCTPAdams, Cumberland36 min
Apr 20, 10:12 PM EDTSpecial Weather StatementCTPColumbia, Lebanon, Schuylkill33 min

Nearby

Tornado Warnings in Pennsylvania, 2015Every tornado warning in 2015Tornadoes in 2015

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.