Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2015

Severe Thunderstorm Warning 25, NWS Philadelphia/Mount Holly

June 1, 2015Chester County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jun 1, 2015, 2:43 PM EDT for Chester 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: Jun 1, 2015, 2:43 PM EDT (18:43 UTC)
Expired: Jun 1, 2015, 3:15 PM EDT
In force: 32 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon

County Chester County, PA

The radar

The Philadelphia radar (KDIX), 100 km from the middle of the area, began a volume at 18:47 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 nearest sounding before it

Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 6.7 hours before the alert went out and 67 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: 355 J/kg
Mixed-layer CIN: -69 J/kg
Mixed-layer LCL: 779 m above ground
0-6 km bulk shear: 19 kt
0-1 km storm-relative helicity: 89 m²/s²
0-3 km storm-relative helicity: 102 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

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

632 
WUUS51 KPHI 011843
SVRPHI
PAC029-011930-
/O.NEW.KPHI.SV.W.0025.150601T1843Z-150601T1930Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
243 PM EDT MON JUN 1 2015

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ  HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  CENTRAL CHESTER COUNTY IN SOUTHEASTERN PENNSYLVANIA...

* UNTIL 330 PM EDT

* AT 241 PM EDT...DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM 
  CAPABLE OF PRODUCING QUARTER SIZE HAIL AND DAMAGING WINDS TO 
  60 MPH THIS STORM WAS LOCATED OVER COCHRANVILLE...OR 14 
  MILES WEST OF WEST CHESTER...AND MOVING EAST AT 25 MPH.

*  THUNDERSTORM CAN OCCASIONALLY PRODUCE BRIEF TORNADOES
   WITH WIND DAMAGE. ALTHOUGH NOT IMMEDIATELY
   LIKELY...FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM
   ON THE LOWEST FLOOR OF YOUR HOME OR BUSINESS. 
   THIS STORM HAS THE POTENTIAL TO CAUSE
   INJURY AND DAMAGE TO PROPERTY.

* LOCATIONS IMPACTED INCLUDE...
  WEST CHESTER...COATESVILLE...WESTTOWN...DOWNINGTOWN...KENNETT
  SQUARE...PARKESBURG...WEST GROVE...MARSHALLTON...COCHRANVILLE...
  PAOLI...CHEYNEY...LIONVILLE-MARCHWOOD...HOCKESSIN...WEST GOSHEN...
  MALVERN...ATGLEN...SOUTH COATESVILLE...AVONDALE...MODENA AND
  THORNDALE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEVERE THUNDERSTORMS PRODUCE DAMAGING WINDS...LARGE HAIL...DEADLY
LIGHTNING AND VERY HEAVY RAIN. FOR YOUR PROTECTION...MOVE TO AN
INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR HOME OR BUSINESS. HEAVY
RAINS FLOOD ROADS QUICKLY SO DO NOT DRIVE INTO AREAS WHERE WATER
COVERS THE ROAD.


&&

LAT...LON 4009 7544 4001 7542 4000 7545 3998 7544
      3995 7551 3992 7553 3988 7559 3985 7559
      3984 7558 3984 7559 3980 7569 3979 7595
      3996 7599
TIME...MOT...LOC 1841Z 260DEG 21KT 3990 7588 

$$
 
TFG

2 follow-up statements

149 
WWUS51 KPHI 011900
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
300 PM EDT MON JUN 1 2015

PAC029-011930-
/O.CON.KPHI.SV.W.0025.000000T0000Z-150601T1930Z/
CHESTER PA-
300 PM EDT MON JUN 1 2015

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 330 PM EDT
FOR CENTRAL CHESTER COUNTY...

AT 259 PM EDT...DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM CAPABLE
OF PRODUCING QUARTER SIZE HAIL AND DAMAGING WINDS IN EXCESS OF 60
MPH. THIS STORM WAS LOCATED NEAR KENNETT SQUARE...OR 9 MILES WEST OF
WEST CHESTER...MOVING EAST AT 20 MPH.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEVERE THUNDERSTORMS PRODUCE DAMAGING WINDS...LARGE HAIL...DEADLY
LIGHTNING AND VERY HEAVY RAIN. FOR YOUR PROTECTION MOVE TO AN
INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR HOME OR BUSINESS. HEAVY
RAINS FLOOD ROADS QUICKLY SO DO NOT DRIVE INTO AREAS WHERE WATER
COVERS THE ROAD.

&&

LAT...LON 4001 7542 4000 7545 3998 7544 3995 7551
      3992 7553 3988 7559 3987 7564 3986 7568
      3986 7572 3985 7577 3986 7588 3996 7589
      4006 7543
TIME...MOT...LOC 1859Z 261DEG 18KT 3991 7577 

$$

316 
WWUS51 KPHI 011915
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
315 PM EDT MON JUN 1 2015

PAC029-011924-
/O.CAN.KPHI.SV.W.0025.000000T0000Z-150601T1930Z/
CHESTER PA-
315 PM EDT MON JUN 1 2015

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL CHESTER COUNTY IS
CANCELLED...
                
THE STORM WHICH PROMPTED THE WARNING HAS WEAKENED BELOW SEVERE
LIMITS...AND NO LONGER POSES AN IMMEDIATE THREAT TO LIFE OR PROPERTY.
THEREFORE THE WARNING HAS BEEN CANCELLED. HOWEVER HEAVY RAIN IS STILL
POSSIBLE WITH THIS THUNDERSTORM.

LAT...LON 4001 7542 4000 7545 3998 7544 3995 7551
      3992 7553 3988 7559 3987 7564 3986 7568
      3986 7572 3985 7577 3986 7588 3996 7589
      4006 7543
TIME...MOT...LOC 1912Z 260DEG 21KT 3993 7566 

$$

MEOLA

The office that day

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

Issued	Product	Office	Counties	Lasted
May 31, 9:44 PM EDT	Areal Flood Advisory	PHI	Bucks	5 hr
May 31, 11:10 PM EDT	Special Weather Statement	PHI	Lebanon	65 min
May 31, 11:47 PM EDT	Special Weather Statement	PHI	Chester	58 min
May 31, 11:59 PM EDT	Special Weather Statement	PHI	Berks	31 min
Jun 1, 12:14 AM EDT	Special Weather Statement	PHI	Chester	31 min
Jun 1, 12:21 AM EDT	Areal Flood Advisory	PHI	Berks, Chester, Lehigh, Montgomery	114 min
Jun 1, 12:44 AM EDT	Special Weather Statement	PHI	Chester, Montgomery	46 min
Jun 1, 1:28 AM EDT	Special Weather Statement	PHI	Bucks, Delaware, Montgomery, Philadelphia	47 min
Jun 1, 1:57 AM EDT	Areal Flood Advisory	PHI	Bucks	3 hr
Jun 1, 2:17 AM EDT	Special Weather Statement	PHI	Philadelphia	43 min
Jun 1, 2:55 AM EDT	Areal Flood Advisory	PHI	Bucks, Delaware, Montgomery, Philadelphia	2 hr
Jun 1, 4:20 AM EDT	Flash Flood Watch	PHI	Bucks, Chester, Delaware, Montgomery, Philadelphia	26 hr
Jun 1, 5:56 AM EDT	Areal Flood Advisory	PHI	Chester, Delaware, Montgomery, Philadelphia	3 hr
Jun 1, 2:14 PM EDT	Special Weather Statement	PHI	Chester	61 min
Jun 1, 4:55 PM EDT	Areal Flood Advisory	PHI	Delaware, Montgomery, Philadelphia	3 hr

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2015 Every severe thunderstorm warning 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.