Alert archive / Delaware / Severe Thunderstorm Warnings in 2015

Severe Thunderstorm Warning 53, NWS Philadelphia/Mount Holly

June 20, 2015Kent County, Sussex County, Delaware; Caroline County, Maryland

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jun 20, 2015, 10:32 PM EDT for Kent County, Sussex County, Delaware; Caroline County, Maryland. It was in force for 46 min. 2 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Jun 20, 2015, 10:32 PM EDT (02:32 UTC)
Expired
Jun 20, 2015, 11:18 PM EDT
In force
46 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon

Counties Kent County, DE, Sussex County, DE, Caroline County, MD

The radar

The Dover AFB radar (KDOX), 16 km from the middle of the area, began a volume at 02:31 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.

What was reported inside it

TimeReportWhereRemark
Jun 20, 11:13 PM EDTTSTM WND DMGGeorgetown, DETREE DOWN ON MORRIS MILL ROAD
Jun 20, 11:13 PM EDTTSTM WND DMGGeorgetown, DEWIRES DOWN ON BRIDGEVILLE ROAD

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Jun 20, 8:56 PM EDTSevere Thunderstorm WatchSPC4 hr

The nearest sounding before it

Wallops Is Stn, VA (KWAL), launched 00:00Z, 2.5 hours before the alert went out and 86 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, Wallops Is Stn, VA at 00:00Z on 2015-06-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 261 joules per kilogram.LCLLFCEL10008507005003002001001 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, Wallops Is Stn, VA at 00:00Z on 2015-06-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 16 square meters per square second.193958Sfc1 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
261 J/kg
Mixed-layer CIN
-134 J/kg
Mixed-layer LCL
1179 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
16 m²/s²
0-3 km storm-relative helicity
75 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.

748 
WUUS51 KPHI 210232
SVRPHI
DEC001-005-MDC011-210330-
/O.NEW.KPHI.SV.W.0053.150621T0232Z-150621T0330Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1032 PM EDT SAT JUN 20 2015

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ  HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SUSSEX COUNTY IN SOUTHERN DELAWARE...
  SOUTHERN KENT COUNTY IN CENTRAL DELAWARE...
  CAROLINE COUNTY IN EASTERN MARYLAND...

* UNTIL 1130 PM EDT

* AT 1031 PM EDT...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 NEAR
  GRIFFIN TO NEAR HURLOCK TO 8 MILES SOUTH OF VIENNA...AND MOVING
  NORTHEAST AT 35 MPH.

* LOCATIONS IMPACTED INCLUDE...
  DOVER...GEORGETOWN...MILFORD...SEAFORD...DENTON...MILLSBORO...
  LAUREL...HARRINGTON...CAMDEN...LEWES...FEDERALSBURG...MILTON...
  SELBYVILLE...BRIDGEVILLE...GREENSBORO...RIDGELY...DELMAR...
  DAGSBORO...MILLVILLE AND ELLENDALE.

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.

THESE STORMS HAVE A HISTORY OF PRODUCING WIND DAMAGE. THIS IS A VERY
DANGEROUS SITUATION. SEEK SHELTER NOW INSIDE A STURDY STRUCTURE AND
STAY AWAY FROM WINDOWS.
 
&&

LAT...LON 3846 7569 3865 7571 3870 7589 3895 7595
      3896 7594 3918 7541 3891 7531 3879 7510
      3880 7509 3869 7507 3868 7507 3869 7514
      3864 7513 3862 7508 3866 7507 3861 7506
      3859 7521 3860 7506 3845 7505
TIME...MOT...LOC 0231Z 246DEG 31KT 3890 7590 3866 7584 3837 7586 

$$

AMC
3 follow-up statements
807 
WWUS51 KPHI 210253
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1053 PM EDT SAT JUN 20 2015

DEC001-005-MDC011-210330-
/O.CON.KPHI.SV.W.0053.000000T0000Z-150621T0330Z/
SUSSEX DE-KENT DE-CAROLINE MD-
1053 PM EDT SAT JUN 20 2015

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1130 PM EDT
FOR SUSSEX...SOUTHERN KENT AND CAROLINE COUNTIES...

AT 1053 PM EDT...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 NEAR
SANDTOWN TO NEAR BRIDGEVILLE TO NEAR DELMAR...MOVING NORTHEAST AT 40
MPH.

LOCATIONS IMPACTED INCLUDE...
DOVER...GEORGETOWN...MILFORD...SEAFORD...DENTON...MILLSBORO...
LAUREL...HARRINGTON...CAMDEN...LEWES...FEDERALSBURG...MILTON...
SELBYVILLE...BRIDGEVILLE...GREENSBORO...RIDGELY...DELMAR...
DAGSBORO...MILLVILLE AND ELLENDALE.

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.

THESE STORMS HAVE A HISTORY OF PRODUCING WIND DAMAGE. THIS IS A VERY
DANGEROUS SITUATION. SEEK SHELTER NOW INSIDE A STURDY STRUCTURE AND
STAY AWAY FROM WINDOWS.
 
&&

LAT...LON 3846 7569 3865 7571 3870 7589 3895 7595
      3896 7594 3918 7541 3891 7531 3879 7510
      3880 7509 3869 7507 3868 7507 3869 7514
      3864 7513 3862 7508 3866 7507 3861 7506
      3859 7521 3860 7506 3845 7505
TIME...MOT...LOC 0253Z 235DEG 33KT 3903 7566 3879 7560 3850 7562 

$$

SFJ
569 
WWUS51 KPHI 210304
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1104 PM EDT SAT JUN 20 2015

MDC011-210312-
/O.CAN.KPHI.SV.W.0053.000000T0000Z-150621T0330Z/
CAROLINE MD-
1104 PM EDT SAT JUN 20 2015

...THE SEVERE THUNDERSTORM WARNING FOR CAROLINE COUNTY IS
CANCELLED...

THE STORMS WHICH PROMPTED THE WARNING HAVE MOVED OUT OF THE WARNED 
AREA. THEREFORE THE WARNING HAS BEEN CANCELLED.

LAT...LON 3846 7569 3876 7569 3903 7571 3918 7541
      3891 7531 3879 7510 3880 7509 3869 7507
      3868 7507 3869 7514 3864 7513 3862 7508
      3866 7507 3861 7506 3859 7521 3860 7506
      3845 7505
TIME...MOT...LOC 0302Z 246DEG 31KT 3906 7558 3882 7552 3853 7554 

$$

DEC001-005-210330-
/O.CON.KPHI.SV.W.0053.000000T0000Z-150621T0330Z/
SUSSEX DE-KENT DE-
1104 PM EDT SAT JUN 20 2015

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1130 PM EDT
FOR SUSSEX AND SOUTHERN KENT COUNTIES...

AT 1102 PM EDT...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 WOODSIDE
TO NEAR ELLENDALE TO NEAR LAUREL...MOVING NORTHEAST AT 35 MPH.

LOCATIONS IMPACTED INCLUDE...
DOVER...GEORGETOWN...MILFORD...SEAFORD...MILLSBORO...LAUREL...
HARRINGTON...CAMDEN...LEWES...MILTON...SELBYVILLE...BRIDGEVILLE...
DELMAR...DAGSBORO...MILLVILLE...ELLENDALE...BOWERS...WOODSIDE...VIOLA
AND HENLOPEN ACRES.

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.

THESE STORMS HAVE A HISTORY OF PRODUCING WIND DAMAGE. SEEK SHELTER 
NOW INSIDE A STURDY STRUCTURE AND STAY AWAY FROM WINDOWS.
 
&&

LAT...LON 3846 7569 3876 7569 3903 7571 3918 7541
      3891 7531 3879 7510 3880 7509 3869 7507
      3868 7507 3869 7514 3864 7513 3862 7508
      3866 7507 3861 7506 3859 7521 3860 7506
      3845 7505
TIME...MOT...LOC 0302Z 246DEG 31KT 3906 7558 3882 7552 3853 7554 

$$

AMC
787 
WWUS51 KPHI 210318
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1118 PM EDT SAT JUN 20 2015

DEC001-005-210327-
/O.CAN.KPHI.SV.W.0053.000000T0000Z-150621T0330Z/
SUSSEX DE-KENT DE-
1118 PM EDT SAT JUN 20 2015

...THE SEVERE THUNDERSTORM WARNING FOR SUSSEX AND SOUTHERN KENT
COUNTIES IS CANCELLED...
            
THE STORMS WHICH PROMPTED THE WARNING HAVE WEAKENED BELOW SEVERE
LIMITS...AND NO LONGER POSES AN IMMEDIATE THREAT TO LIFE OR PROPERTY.
THEREFORE THE WARNING HAS BEEN CANCELLED.

LAT...LON 3846 7569 3876 7569 3903 7571 3918 7541
      3891 7531 3879 7510 3880 7509 3869 7507
      3868 7507 3869 7514 3864 7513 3862 7508
      3866 7507 3861 7506 3859 7521 3860 7506
      3845 7505
TIME...MOT...LOC 0315Z 246DEG 31KT 3911 7545 3887 7539 3858 7541 

$$

AMC

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 20, 8:31 PM EDTSpecial Weather StatementPHIKent, New Castle, Sussex3 hr
Jun 21, 12:25 AM EDTSpecial Weather StatementPHISussex35 min
Jun 21, 12:35 AM EDTSevere Thunderstorm WarningPHISussex55 min
Jun 21, 12:47 AM EDTAreal Flood AdvisoryPHINew Castle4 hr
Jun 21, 5:12 AM EDTAreal Flood AdvisoryPHIKent, New Castle, Sussex4 hr
Jun 20, 9:35 PM EDTSevere Thunderstorm WarningPHICaroline, Talbot55 min
Jun 20, 9:49 PM EDTSevere Thunderstorm WarningPHICecil56 min
Jun 20, 9:57 PM EDTSevere Thunderstorm WarningPHICaroline, Kent, Queen Anne's63 min
Jun 21, 4:45 AM EDTSpecial Weather StatementPHIQueen Anne's30 min

Nearby

Severe Thunderstorm Warnings in Delaware, 2015Severe Thunderstorm Warnings in Maryland, 2015Every 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.