Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2016

Severe Thunderstorm Warning 150, NWS Philadelphia/Mount Holly

July 28, 2016Chester County, Delaware County, Pennsylvania; New Castle County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 28, 2016, 1:24 PM EDT for Chester County, Delaware County, Pennsylvania; New Castle County, Delaware. It was in force for 51 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 28, 2016, 1:24 PM EDT (17:24 UTC)
Expired: Jul 28, 2016, 2:15 PM EDT
In force: 51 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Tornado: Possible
Hail: 0.75 in
Wind: 60.0 mph

Counties New Castle County, DE, Chester County, PA, Delaware County, PA

The radar

The Philadelphia radar (KDIX), 96 km from the middle of the area, began a volume at 17:25 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 nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 5.4 hours before the alert went out and 190 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: 552 J/kg
Mixed-layer CIN: -98 J/kg
Mixed-layer LCL: 1083 m above ground
0-6 km bulk shear: 29 kt
0-1 km storm-relative helicity: 13 m²/s²
0-3 km storm-relative helicity: 87 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.8

Open this sounding in Storm Lab

The text

As transmitted.

798 
WUUS51 KPHI 281724
SVRPHI
DEC003-PAC029-045-281815-
/O.NEW.KPHI.SV.W.0150.160728T1724Z-160728T1815Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
124 PM EDT THU JUL 28 2016

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ  HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHEASTERN NEW CASTLE COUNTY IN NORTHERN DELAWARE...
  CENTRAL CHESTER COUNTY IN SOUTHEASTERN PENNSYLVANIA...
  DELAWARE COUNTY IN SOUTHEASTERN PENNSYLVANIA...

* UNTIL 215 PM EDT

* AT 124 PM EDT...A SEVERE THUNDERSTORM WAS LOCATED OVER
  MARSHALLTON... OR NEAR WEST CHESTER...MOVING EAST AT 20 MPH.

  HAZARD...60 MPH WIND GUSTS. 

  SOURCE...RADAR INDICATED. 

  IMPACT...EXPECT DAMAGE TO ROOFS...SIDING...AND TREES. 

* LOCATIONS IMPACTED INCLUDE...
  WILMINGTON...WEST CHESTER...CHESTER...WESTTOWN...DOWNINGTOWN...
  SWARTHMORE...ARDEN...MARSHALLTON...NETHER PROVIDENCE TOWNSHIP...
  CHELSEA...ELAM...CHEYNEY...DREXEL HILL...TALLEYVILLE...LIMA...
  CHESTER TOWNSHIP...CONCORDVILLE...GRADYVILLE...
  BROOMALL AND WEST GOSHEN.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
BUILDING.

IN ADDITION TO LARGE HAIL AND DAMAGING WINDS...FREQUENT CLOUD TO
GROUND LIGHTNING IS OCCURRING WITH THIS STORM. MOVE INDOORS
IMMEDIATELY. REMEMBER...IF YOU CAN HEAR THUNDER...YOU ARE CLOSE
ENOUGH TO BE STRUCK BY LIGHTNING.

TORRENTIAL RAINFALL IS OCCURRING WITH THIS STORM...AND MAY LEAD TO
FLASH FLOODING. DO NOT DRIVE YOUR VEHICLE THROUGH FLOODED ROADWAYS.

&&

LAT...LON 4001 7577 3995 7528 3983 7537 3980 7541
      3979 7541 3977 7546 3974 7547 3990 7580
TIME...MOT...LOC 1724Z 289DEG 16KT 3992 7571 

TORNADO...POSSIBLE
HAIL...<.75IN
WIND...60MPH
 
$$

JRK

1 follow-up statement

355 
WWUS51 KPHI 281801
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
201 PM EDT THU JUL 28 2016

DEC003-PAC029-045-281815-
/O.CON.KPHI.SV.W.0150.000000T0000Z-160728T1815Z/
NEW CASTLE DE-CHESTER PA-DELAWARE PA-
201 PM EDT THU JUL 28 2016

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 215 PM EDT
FOR NORTHEASTERN NEW CASTLE...SOUTHEASTERN CHESTER AND DELAWARE
COUNTIES...

AT 159 PM EDT...A SEVERE THUNDERSTORM WAS LOCATED OVER
CONCORDVILLE...OR 8 MILES SOUTHEAST OF WEST CHESTER...MOVING EAST AT
20 MPH.

HAZARD...60 MPH WIND GUSTS. 

SOURCE...RADAR INDICATED. 

IMPACT...EXPECT DAMAGE TO ROOFS...SIDING...AND TREES. 

LOCATIONS IMPACTED INCLUDE...
WILMINGTON...WEST CHESTER...CHESTER...WESTTOWN...SWARTHMORE...
ARDEN...MARSHALLTON...NETHER PROVIDENCE TOWNSHIP...CHELSEA...ELAM...
CHEYNEY...DREXEL HILL...TALLEYVILLE...LIMA...CHESTER TOWNSHIP...
CONCORDVILLE...GRADYVILLE...BROOMALL...WEST GOSHEN AND LANSDOWNE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
BUILDING.

TORRENTIAL RAINFALL IS OCCURRING WITH THIS STORM...AND MAY LEAD TO
FLASH FLOODING. DO NOT DRIVE YOUR VEHICLE THROUGH FLOODED ROADWAYS.

&&

LAT...LON 4000 7569 3995 7528 3983 7537 3980 7541
      3979 7541 3977 7546 3974 7547 3987 7574
TIME...MOT...LOC 1759Z 289DEG 16KT 3987 7551 

TORNADO...POSSIBLE
HAIL...<.75IN
WIND...60MPH
 
$$

JJM

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 28, 12:58 PM EDT	Severe Thunderstorm Warning	PHI	Chester	47 min
Jul 28, 2:30 PM EDT	Severe Thunderstorm Warning	PHI	Delaware, Montgomery, Philadelphia	45 min
Jul 28, 2:36 PM EDT	Areal Flood Advisory	PHI	Chester, Delaware, Montgomery, Philadelphia	4 hr
Jul 28, 3:28 PM EDT	Severe Thunderstorm Warning	PHI	Berks	27 min
Jul 28, 3:41 PM EDT	Areal Flood Advisory	PHI	Berks	4 hr
Jul 28, 4:50 PM EDT	Areal Flood Advisory	PHI	Berks	4 hr
Jul 28, 1:20 PM EDT	Severe Thunderstorm Warning	PHI	Kent, Sussex	40 min
Jul 28, 1:42 PM EDT	Special Weather Statement	PHI	New Castle	33 min
Jul 28, 1:58 PM EDT	Special Weather Statement	PHI	Sussex	62 min
Jul 28, 2:30 PM EDT	Severe Thunderstorm Warning	PHI	Kent	47 min
Jul 28, 2:44 PM EDT	Areal Flood Advisory	PHI	Kent	4 hr
Jul 28, 3:54 PM EDT	Areal Flood Advisory	PHI	New Castle	4 hr
Jul 28, 4:38 PM EDT	Special Weather Statement	PHI	Kent	52 min
Jul 28, 4:52 PM EDT	Severe Thunderstorm Warning	PHI	Kent	38 min
Jul 28, 4:56 PM EDT	Areal Flood Advisory	PHI	Kent, New Castle	4 hr
Jul 28, 5:24 PM EDT	Severe Thunderstorm Warning	PHI	Kent, Sussex	51 min
Jul 28, 6:12 PM EDT	Special Weather Statement	PHI	Kent	48 min
Jul 28, 6:15 PM EDT	Areal Flood Advisory	PHI	Kent, Sussex	4 hr
Jul 28, 6:25 PM EDT	Severe Thunderstorm Warning	PHI	Kent, Sussex	65 min
Jul 28, 6:53 PM EDT	Areal Flood Advisory	PHI	Sussex	4 hr
Jul 28, 7:22 PM EDT	Special Weather Statement	PHI	Sussex	38 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2016 Severe Thunderstorm Warnings in Delaware, 2016 Every severe thunderstorm warning in 2016

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.