Alert archive / Pennsylvania / Tornado Warnings in 2015

Tornado Warning 3, NWS Philadelphia/Mount Holly

June 23, 2015Chester County, Pennsylvania

NWS Philadelphia/Mount Holly issued this tornado warning at Jun 23, 2015, 5:22 PM EDT for Chester County, Pennsylvania. It was in force for 23 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: Jun 23, 2015, 5:22 PM EDT (21:22 UTC)
Expired: Jun 23, 2015, 5:45 PM EDT
In force: 23 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon

County Chester County, PA

The radar

The Philadelphia radar (KDIX), 96 km from the middle of the area, began a volume at 21:25 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
Jun 23, 10:20 AM EDT	Severe Thunderstorm Watch	SPC	7 hr
Jun 23, 4:09 PM EDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 9.4 hours before the alert went out and 200 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: 387 J/kg
Mixed-layer CIN: -168 J/kg
Mixed-layer LCL: 1544 m above ground
0-6 km bulk shear: 28 kt
0-1 km storm-relative helicity: 121 m²/s²
0-3 km storm-relative helicity: 24 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.4

Open this sounding in Storm Lab

The text

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

191 
WFUS51 KPHI 232122
TORPHI
PAC029-232145-
/O.NEW.KPHI.TO.W.0003.150623T2122Z-150623T2145Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
522 PM EDT TUE JUN 23 2015

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ  HAS ISSUED A

* TORNADO WARNING FOR...
  CENTRAL CHESTER COUNTY IN SOUTHEASTERN PENNSYLVANIA...

* UNTIL 545 PM EDT
    
* AT 522 PM EDT...DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM
  CAPABLE OF PRODUCING A TORNADO. THIS DANGEROUS STORM WAS LOCATED
  OVER DOWNINGTOWN...OR 7 MILES WEST OF WEST CHESTER...AND MOVING
  EAST AT 35 MPH.

* LOCATIONS IMPACTED INCLUDE...
  WEST CHESTER...COATESVILLE...WESTTOWN...DOWNINGTOWN...CHESTER
  SPRINGS...VALLEY FORGE...MARSHALLTON...PAOLI...
  LIONVILLE-MARCHWOOD...LIONVILLE...RADNOR TOWNSHIP...WEST GOSHEN...
  MALVERN...SOUTH COATESVILLE...MODENA...THORNDALE...DEVON-BERWYN...
  EXTON AND CHESTERBROOK.

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.

&&

LAT...LON 4008 7583 4011 7547 4009 7545 4009 7542
      4006 7539 4007 7536 4004 7541 4003 7540
      4000 7545 3998 7544 3995 7551 3988 7559
      3990 7584
TIME...MOT...LOC 2122Z 271DEG 30KT 4000 7574 

$$

1 follow-up statement

617 
WWUS51 KPHI 232141
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
541 PM EDT TUE JUN 23 2015

PAC029-232150-
/O.EXP.KPHI.TO.W.0003.000000T0000Z-150623T2145Z/
CHESTER PA-
541 PM EDT TUE JUN 23 2015

...THE TORNADO WARNING FOR CENTRAL CHESTER COUNTY WILL EXPIRE AT 545
PM EDT...
    
THE TORNADIC THUNDERSTORM WHICH PROMPTED THE WARNING HAS WEAKENED. 
THEREFORE THE WARNING WILL BE ALLOWED TO EXPIRE.

LAT...LON 4008 7583 4011 7547 4009 7545 4009 7542
      4006 7539 4007 7536 4004 7541 4003 7540
      4000 7545 3998 7544 3995 7551 3988 7559
      3990 7584
TIME...MOT...LOC 2137Z 271DEG 30KT 4000 7574 

$$

The office that day

Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jun 23, 8:30 AM EDT	Special Weather Statement	PHI	Monroe	60 min
Jun 23, 9:10 AM EDT	Special Weather Statement	PHI	Monroe	35 min
Jun 23, 10:37 AM EDT	Special Weather Statement	PHI	Carbon, Monroe	38 min
Jun 23, 11:13 AM EDT	Special Weather Statement	PHI	Monroe	32 min
Jun 23, 1:31 PM EDT	Special Weather Statement	PHI	Carbon, Monroe, Northampton	59 min
Jun 23, 1:41 PM EDT	Severe Thunderstorm Warning	PHI	Carbon, Monroe	49 min
Jun 23, 2:29 PM EDT	Severe Thunderstorm Warning	PHI	Monroe, Northampton	46 min
Jun 23, 3:49 PM EDT	Special Weather Statement	PHI	Berks, Bucks, Chester, Montgomery	86 min
Jun 23, 4:11 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Lehigh	24 min
Jun 23, 4:44 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Chester, Montgomery	61 min
Jun 23, 5:05 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Chester, Delaware, Montgomery	40 min
Jun 23, 5:19 PM EDT	Areal Flood Advisory	PHI	Berks, Chester, Montgomery	4 hr
Jun 23, 5:28 PM EDT	Severe Thunderstorm Warning	PHI	Chester, Delaware	47 min
Jun 23, 5:38 PM EDT	Severe Thunderstorm Warning	PHI	Bucks, Chester, Delaware, Montgomery, Philadelphia	52 min
Jun 23, 5:44 PM EDT	Areal Flood Advisory	PHI	Chester, Delaware, Montgomery, Philadelphia	4 hr
Jun 23, 6:18 PM EDT	Areal Flood Advisory	PHI	Monroe, Northampton	4 hr

Nearby

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