Alert archive / New Jersey / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 13, NWS Philadelphia/Mount Holly

April 5, 2011Caroline County, Talbot County, Maryland; Atlantic County, Cape May County, Cumberland County, New Jersey; Kent County, Sussex County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Apr 5, 2011, 10:20 AM EDT for Caroline County, Talbot County, Maryland; Atlantic County, Cape May County, Cumberland County, New Jersey; Kent County, Sussex County, Delaware. It was in force for 40 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 5, 2011, 10:20 AM EDT (14:20 UTC)
Expired
Apr 5, 2011, 11:00 AM EDT
In force
40 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon

Counties Kent County, DE, Sussex County, DE, Caroline County, MD, Talbot County, MD, Atlantic County, NJ, Cape May County, NJ, Cumberland County, NJ

The radar

The Dover AFB radar (KDOX), 24 km from the middle of the area, began a volume at 14:23 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, 2.3 hours before the alert went out and 77 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, Phillips Aaf/Abe, MD at 12:00Z on 2011-04-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Phillips Aaf/Abe, MD at 12:00Z on 2011-04-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 106 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1186 m above ground
0-6 km bulk shear
79 kt
0-1 km storm-relative helicity
106 m²/s²
0-3 km storm-relative helicity
133 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.

779 
WUUS51 KPHI 051420
SVRPHI
DEC001-005-MDC011-041-NJC001-009-011-051500-
/O.NEW.KPHI.SV.W.0013.110405T1420Z-110405T1500Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1020 AM EDT TUE APR 5 2011

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  KENT COUNTY IN CENTRAL DELAWARE...
  THIS INCLUDES THE CITY OF DOVER...
  SOUTHERN CAROLINE COUNTY IN EASTERN MARYLAND...
  SOUTHEASTERN TALBOT COUNTY IN EASTERN MARYLAND...
  NORTHERN SUSSEX COUNTY IN SOUTHERN DELAWARE...
  THIS INCLUDES THE CITY OF GEORGETOWN...
  SOUTHWESTERN ATLANTIC COUNTY IN SOUTHERN NEW JERSEY...
  NORTHWESTERN CAPE MAY COUNTY IN SOUTHERN NEW JERSEY...
  SOUTHERN CUMBERLAND COUNTY IN SOUTHERN NEW JERSEY...

* UNTIL 1100 AM EDT

* AT 1017 AM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING WINDS IN
  EXCESS OF 60 MPH.  THESE STORMS WERE LOCATED ALONG A LINE EXTENDING
  FROM CHESWOLD TO 8 MILES NORTHWEST OF ANDREWSVILLE TO PRESTON...OR
  ALONG A LINE EXTENDING FROM 8 MILES NORTHWEST OF DOVER TO 18 MILES
  SOUTHEAST OF CENTERVILLE TO 8 MILES EAST OF EASTON...AND MOVING
  EAST AT 35 MPH.

* SEVERE THUNDERSTORMS WILL BE NEAR...
  DOVER SPEEDWAY...WOODSIDE AND CAMDEN AROUND 1025 AM EDT...
  SMITHVILLE...AGNER...FEDERALSBURG AND VIOLA AROUND 1030 AM EDT...
  ANDREWSVILLE AND HARRINGTON AROUND 1035 AM EDT...
  BRIDGEVILLE AROUND 1045 AM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS SEVERE THUNDERSTORM MAY CONTAIN LITTLE OR NO LIGHTNING. DO NOT
WAIT FOR THUNDER BEFORE TAKING COVER. SEEK SHELTER IMMEDIATELY INSIDE
A STURDY STRUCTURE AND STAY AWAY FROM WINDOWS.

&&

LAT...LON 3864 7603 3892 7579 3930 7555 3931 7543
      3924 7539 3931 7532 3935 7480 3916 7491
      3920 7505 3917 7514 3929 7527 3929 7532
      3923 7539 3907 7539 3898 7529 3893 7530
      3879 7516 3867 7527 3865 7573 3869 7586
TIME...MOT...LOC 1420Z 267DEG 30KT 3926 7555 3893 7572
          3873 7590

$$

DRAG
1 follow-up statement
928 
WWUS51 KPHI 051447
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1047 AM EDT TUE APR 5 2011

DEC001-005-MDC011-041-NJC001-009-011-051500-
/O.CON.KPHI.SV.W.0013.000000T0000Z-110405T1500Z/
KENT DE-CAROLINE MD-CUMBERLAND NJ-TALBOT MD-SUSSEX DE-CAPE MAY NJ-
ATLANTIC NJ-
1047 AM EDT TUE APR 5 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1100 AM EDT
FOR SOUTHWESTERN ATLANTIC...NORTHWESTERN CAPE MAY...NORTHERN
SUSSEX...SOUTHEASTERN TALBOT...SOUTHERN CUMBERLAND...SOUTHERN
CAROLINE AND KENT COUNTIES...

AT 1041 AM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING
WINDS IN EXCESS OF 60 MPH.  THESE STORMS WERE LOCATED ALONG A LINE
EXTENDING FROM 8 MILES WEST OF NEWPORT TO HOUSTON TO FEDERALSBURG...
OR ALONG A LINE EXTENDING FROM 13 MILES NORTHEAST OF DOVER TO 15
MILES SOUTH OF DOVER TO 17 MILES WEST OF GEORGETOWN...MOVING EAST AT
35 MPH.

IN SOME CASES THE STRONG EST WIND IS OCCURRING ABOUT 30 MINUTES 
AFTER THE PASSAGE OF THE LINE. 

SEVERE THUNDERSTORMS WILL BE NEAR...
  NEWPORT...FORTESQUE...BIG STONE BEACH AND ELLENDALE BY 1055 AM
  EDT...
  SLAUGHTER BEACH...DIVIDING CREEK...PORT NORRIS AND GEORGETOWN BY
  1100 AM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...PREPARE 
IMMEDIATELY FOR DAMAGING WINDS. PEOPLE OUTSIDE SHOULD MOVE TO A 
SHELTER...PREFERABLY INSIDE A STRONG BUILDING BUT AWAY FROM WINDOWS.

&&

LAT...LON 3864 7603 3892 7579 3930 7555 3931 7543
      3924 7539 3931 7532 3935 7480 3916 7491
      3920 7505 3917 7514 3929 7527 3929 7532
      3923 7539 3907 7539 3898 7529 3893 7530
      3879 7516 3867 7527 3865 7573 3869 7586
TIME...MOT...LOC 1446Z 267DEG 30KT 3927 7527 3894 7544
          3869 7564

$$

DRAG

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 5, 5:01 AM EDTSevere Thunderstorm WarningPHICaroline, Cecil, Kent, Queen Anne's, Talbot74 min
Apr 5, 5:28 AM EDTSevere Thunderstorm WarningPHICaroline, Queen Anne's, Talbot62 min
Apr 5, 8:55 AM EDTSpecial Weather StatementPHICaroline, Cecil, Kent, Queen Anne's, Talbot65 min
Apr 5, 9:37 AM EDTSpecial Weather StatementPHICaroline, Cecil, Kent, Queen Anne's53 min
Apr 5, 3:05 PM EDTFrost AdvisoryPHICaroline, Queen Anne's, Talbot13 hr
Apr 5, 5:58 AM EDTSpecial Weather StatementPHIHunterdon, Morris, Somerset, Sussex, Warren62 min
Apr 5, 6:05 AM EDTSpecial Weather StatementPHIAtlantic, Burlington, Camden, Gloucester, Monmouth, Ocean and 1 more55 min
Apr 5, 6:30 AM EDTSpecial Weather StatementPHIHunterdon, Mercer, Middlesex, Monmouth, Morris, Somerset and 1 more60 min
Apr 5, 6:42 AM EDTSpecial Weather StatementPHICape May, Cumberland63 min
Apr 5, 7:05 AM EDTSpecial Weather StatementPHIMorris55 min
Apr 5, 7:07 AM EDTSpecial Weather StatementPHIBurlington, Middlesex, Monmouth, Ocean53 min
Apr 5, 10:16 AM EDTSevere Thunderstorm WarningPHIAtlantic, Burlington, Camden, Cumberland, Gloucester, Salem44 min
Apr 5, 10:30 AM EDTSpecial Weather StatementPHIMercer, Middlesex, Monmouth, Morris, Somerset60 min
Apr 5, 10:35 AM EDTSpecial Marine WarningPHI55 min
Apr 5, 10:41 AM EDTSevere Thunderstorm WarningPHIAtlantic, Cumberland, Salem19 min
Apr 5, 10:58 AM EDTSpecial Weather StatementPHIAtlantic, Burlington, Camden, Cape May, Cumberland, Middlesex and 2 more92 min
Apr 5, 11:00 AM EDTSevere Thunderstorm WarningPHIBurlington, Monmouth, Ocean30 min
Apr 5, 11:09 AM EDTSpecial Marine WarningPHI96 min
Apr 5, 11:45 AM EDTSpecial Marine WarningPHI60 min
Apr 5, 2:57 PM EDTSmall Craft AdvisoryPHI27 hr

Nearby

Severe Thunderstorm Warnings in New Jersey, 2011Severe Thunderstorm Warnings in Maryland, 2011Severe Thunderstorm Warnings in Delaware, 2011Every severe thunderstorm warning in 2011

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.