Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2015

Severe Thunderstorm Warning 73, NWS Philadelphia/Mount Holly

June 30, 2015Chester County, Pennsylvania; Cecil County, Maryland

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jun 30, 2015, 2:41 PM EDT for Chester County, Pennsylvania; Cecil County, Maryland. It was in force for 49 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 30, 2015, 2:41 PM EDT (18:41 UTC)
Expired: Jun 30, 2015, 3:30 PM EDT
In force: 49 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon

Counties Cecil County, MD, Chester County, PA

The radar

The Dover AFB radar (KDOX), 104 km from the middle of the area, began a volume at 18:42 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.

Issued	Product	Office	Lasted
Jun 30, 1:21 PM EDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 6.7 hours before the alert went out and 25 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: 600 J/kg
Mixed-layer CIN: -45 J/kg
Mixed-layer LCL: 728 m above ground
0-6 km bulk shear: 38 kt
0-1 km storm-relative helicity: 128 m²/s²
0-3 km storm-relative helicity: 128 m²/s²
Significant tornado parameter: 0.3
Supercell composite: 2.9

Open this sounding in Storm Lab

The text

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

325 
WUUS51 KPHI 301841
SVRPHI
MDC015-PAC029-301930-
/O.NEW.KPHI.SV.W.0073.150630T1841Z-150630T1930Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
241 PM EDT TUE JUN 30 2015

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ  HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  CENTRAL CECIL COUNTY IN NORTHEASTERN MARYLAND...
  SOUTH 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 IN EXCESS
  OF 60 MPH. THIS STORM WAS LOCATED OVER HAVRE DE GRACE...OR NEAR
  ABERDEEN...AND MOVING NORTHEAST AT 25 MPH.

* LOCATIONS IMPACTED INCLUDE...
  ELKTON...CALVERT...OXFORD...NORTH EAST...RISING SUN...
  CHARLESTOWN...BLAKE...PLEASANT HILL...ANDORA...KEMBLESVILLE...
  FARMINGTON...RICHARDSMERE...BARKSDALE...WEST NOTTINGHAM...FAIR
  HILL...GLEN WESTOVER...WOODLAWN...APPLETON...CHERRY HILL AND BAY
  VIEW.

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.

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.

&&

LAT...LON 3985 7593 3973 7577 3972 7579 3962 7579
      3952 7598 3955 7603 3955 7608 3963 7615
      3966 7617
TIME...MOT...LOC 1841Z 225DEG 21KT 3958 7611 

$$

HEAVENER

2 follow-up statements

935 
WWUS51 KPHI 301902 RRA
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
302 PM EDT TUE JUN 30 2015

MDC015-PAC029-301930-
/O.CON.KPHI.SV.W.0073.000000T0000Z-150630T1930Z/
CECIL MD-CHESTER PA-
302 PM EDT TUE JUN 30 2015

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 330 PM EDT
FOR NORTHERN CECIL AND SOUTH CENTRAL CHESTER COUNTIES...

AT 302 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 OVER ZION...OR 10 MILES NORTHWEST OF
ELKTON...MOVING NORTHEAST AT 25 MPH.

LOCATIONS IMPACTED INCLUDE...
ELKTON...CALVERT...OXFORD...NORTH EAST...RISING SUN...CHARLESTOWN...
BLAKE...PLEASANT HILL...ANDORA...KEMBLESVILLE...FARMINGTON...
BARKSDALE...FAIR HILL...GLEN WESTOVER...APPLETON...CHERRY HILL...BAY
VIEW...LOMBARD AND ZION.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEVERE THUNDERSTORMS PRODUCE DAMAGING WINDS...DESTRUCTIVE 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.

IF YOU ARE IN THE PATH OF THIS STORM...PREPARE IMMEDIATELY FOR LARGE
HAIL AND DAMAGING WINDS. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...
PREFERABLY INSIDE A STRONG BUILDING AND AWAY FROM WINDOWS.

&&

LAT...LON 3985 7593 3973 7577 3972 7579 3962 7579
      3957 7597 3960 7604 3972 7608
TIME...MOT...LOC 1902Z 225DEG 21KT 3967 7600 

$$

HEAVENER

213 
WWUS51 KPHI 301906
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
306 PM EDT TUE JUN 30 2015

MDC015-PAC029-301930-
/O.CON.KPHI.SV.W.0073.000000T0000Z-150630T1930Z/
CECIL MD-CHESTER PA-
306 PM EDT TUE JUN 30 2015

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 330 PM EDT
FOR NORTHERN CECIL AND SOUTH CENTRAL CHESTER COUNTIES...

AT 304 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 OVER GILBERTSVILLE...OR 15 MILES EAST OF
READING. THIS STORM WAS MOVING NORTHEAST AT 20 MPH. 

LOCATIONS IMPACTED INCLUDE...
ELKTON...CALVERT...OXFORD...NORTH EAST...RISING SUN...CHARLESTOWN...
BLAKE...PLEASANT HILL...ANDORA...KEMBLESVILLE...FARMINGTON...
BARKSDALE...FAIR HILL...GLEN WESTOVER...APPLETON...CHERRY HILL...BAY
VIEW...LOMBARD AND ZION.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEVERE THUNDERSTORMS PRODUCE DAMAGING WINDS...DESTRUCTIVE 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.

IF YOU ARE IN THE PATH OF THIS STORM...PREPARE IMMEDIATELY FOR LARGE
HAIL AND DAMAGING WINDS. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...
PREFERABLY INSIDE A STRONG BUILDING AND AWAY FROM WINDOWS.

&&

LAT...LON 3985 7593 3973 7577 3972 7579 3962 7579
      3957 7597 3960 7604 3972 7608
TIME...MOT...LOC 1904Z 225DEG 21KT 4031 7563 

$$

MWG

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 30, 10:01 AM EDT	Areal Flood Advisory	PHI	Carbon, Monroe	4 hr
Jun 30, 12:37 PM EDT	Areal Flood Advisory	PHI	Berks	4 hr
Jun 30, 12:47 PM EDT	Special Weather Statement	PHI	Berks	43 min
Jun 30, 1:08 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Lehigh	52 min
Jun 30, 1:47 PM EDT	Special Weather Statement	PHI	Lehigh	43 min
Jun 30, 1:48 PM EDT	Flash Flood Warning	PHI	Berks	4 hr
Jun 30, 1:55 PM EDT	Special Weather Statement	PHI	Chester	50 min
Jun 30, 2:00 PM EDT	Tornado Warning	PHI	Berks, Chester	30 min
Jun 30, 2:05 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Carbon, Lehigh, Monroe, Northampton	55 min
Jun 30, 2:13 PM EDT	Tornado Warning	PHI	Lehigh	32 min
Jun 30, 2:19 PM EDT	Special Weather Statement	PHI	Chester	26 min
Jun 30, 2:26 PM EDT	Areal Flood Advisory	PHI	Berks, Chester	4 hr
Jun 30, 2:34 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Chester, Montgomery	56 min
Jun 30, 2:42 PM EDT	Tornado Warning	PHI	Lehigh, Northampton	33 min
Jun 30, 2:48 PM EDT	Special Weather Statement	PHI	Chester	57 min
Jun 30, 2:52 PM EDT	Severe Thunderstorm Warning	PHI	Chester, Delaware, Montgomery	38 min
Jun 30, 2:55 PM EDT	Flash Flood Warning	PHI	Berks, Lehigh, Northampton	4 hr
Jun 30, 3:00 PM EDT	Areal Flood Advisory	PHI	Bucks, Monroe, Northampton	4 hr
Jun 30, 3:00 PM EDT	Severe Thunderstorm Warning	PHI	Lehigh, Northampton	60 min
Jun 30, 3:08 PM EDT	Areal Flood Advisory	PHI	Chester	4 hr
Jun 30, 3:22 PM EDT	Tornado Warning	PHI	Chester, Delaware, Montgomery	23 min
Jun 30, 3:25 PM EDT	Severe Thunderstorm Warning	PHI	Chester	37 min
Jun 30, 3:31 PM EDT	Special Weather Statement	PHI	Lehigh	44 min
Jun 30, 3:37 PM EDT	Areal Flood Advisory	PHI	Carbon, Lehigh, Monroe, Northampton	4 hr
Jun 30, 3:43 PM EDT	Severe Thunderstorm Warning	PHI	Chester, Delaware, Philadelphia	47 min
Jun 30, 3:45 PM EDT	Severe Thunderstorm Warning	PHI	Bucks, Chester, Delaware, Montgomery, Philadelphia	45 min
Jun 30, 3:47 PM EDT	Severe Thunderstorm Warning	PHI	Northampton	43 min
Jun 30, 3:54 PM EDT	Flash Flood Watch	PHI	Berks, Bucks, Carbon, Chester, Delaware, Lehigh and 4 more	13 hr
Jun 30, 3:57 PM EDT	Areal Flood Advisory	PHI	Bucks, Chester, Delaware, Montgomery, Philadelphia	4 hr
Jun 30, 4:22 PM EDT	Special Weather Statement	PHI	Monroe	23 min
Jun 30, 4:29 PM EDT	Special Weather Statement	PHI	Delaware, Philadelphia	31 min
Jun 30, 4:31 PM EDT	Special Weather Statement	PHI	Carbon	29 min
Jun 30, 4:58 PM EDT	Areal Flood Advisory	PHI	Delaware, Montgomery, Philadelphia	3 hr
Jun 30, 4:59 PM EDT	Special Weather Statement	PHI	Philadelphia	61 min
Jun 30, 5:03 PM EDT	Special Weather Statement	PHI	Monroe	27 min
Jun 30, 5:51 PM EDT	Special Weather Statement	PHI	Monroe	24 min
Jun 30, 6:03 PM EDT	Flash Flood Warning	PHI	Carbon, Monroe	11 hr
Jun 30, 6:28 PM EDT	Severe Thunderstorm Warning	PHI	Monroe, Northampton	47 min
Jun 30, 7:13 PM EDT	Severe Thunderstorm Warning	PHI	Monroe	62 min
Jun 30, 2:34 PM EDT	Special Weather Statement	PHI	Cecil	26 min
Jun 30, 4:06 PM EDT	Special Weather Statement	PHI	Kent	39 min
Jun 30, 4:32 PM EDT	Severe Thunderstorm Warning	PHI	Caroline, Kent, Queen Anne's, Talbot	43 min
Jun 30, 5:14 PM EDT	Special Weather Statement	PHI	Queen Anne's	31 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2015 Severe Thunderstorm Warnings in Maryland, 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.