Alert archive / Delaware / Severe Thunderstorm Warnings in 2019

Severe Thunderstorm Warning 345, NWS Philadelphia/Mount Holly

August 7, 2019Kent County, Sussex County, Delaware; Caroline County, Maryland

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 7, 2019, 6:39 PM EDT for Kent County, Sussex County, Delaware; Caroline County, Maryland. 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
Aug 7, 2019, 6:39 PM EDT (22:39 UTC)
Expired
Aug 7, 2019, 7:30 PM EDT
In force
51 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

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

The radar

The Dover AFB radar (KDOX), 4 km from the middle of the area, began a volume at 22:38 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.

IssuedProductOfficeLasted
Aug 7, 2:10 PM EDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Wallops Is Stn, VA (KWAL), launched 12:00Z, 10.7 hours before the alert went out and 100 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 12:00Z on 2019-08-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1339 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 12:00Z on 2019-08-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 43 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
1339 J/kg
Mixed-layer CIN
-52 J/kg
Mixed-layer LCL
1118 m above ground
0-6 km bulk shear
31 kt
0-1 km storm-relative helicity
43 m²/s²
0-3 km storm-relative helicity
60 m²/s²
Significant tornado parameter
0.2
Supercell composite
1.1

Open this sounding in Storm Lab

The text

As transmitted.

068 
WUUS51 KPHI 072239
SVRPHI
DEC001-005-MDC011-072330-
/O.NEW.KPHI.SV.W.0345.190807T2239Z-190807T2330Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
639 PM EDT Wed Aug 7 2019

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Western Sussex County in southern Delaware...
  Southern Kent County in central Delaware...
  Southeastern Caroline County in eastern Maryland...

* Until 730 PM EDT.

* At 638 PM EDT, severe thunderstorms were located along a line
  extending from Sandtown to near Smithville to near Sharptown,
  moving east at 30 mph.

  HAZARD...60 mph wind gusts and penny size hail.

  SOURCE...Radar indicated.

  IMPACT...Damage to roofs, siding, trees, and power lines is 
           possible.

* Locations impacted include...
  Dover, Georgetown, Milford, Seaford, Millsboro, Laurel, Harrington,
  Camden, Milton, Bridgeville, Ellendale, Bowers, Woodside, Viola,
  Rising Sun-Lebanon, Dover Base Housing, Sandtown, Andrewsville,
  Rising Sun and Sycamore.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

To report severe weather, contact your nearest law enforcement
agency. They will send your report to the National Weather Service
office in Mount Holly NJ.

In addition to large hail and damaging winds, frequent cloud to
ground lightning is occurring with these storms. Move indoors
immediately. Remember, if you can hear thunder, you are close enough
to be struck by lightning.

Torrential rainfall is occurring with these storms, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3864 7571 3868 7576 3877 7572 3907 7576
      3914 7541 3907 7541 3901 7533 3894 7531
      3893 7532 3883 7521 3879 7521 3856 7532
      3854 7570
TIME...MOT...LOC 2238Z 255DEG 27KT 3902 7569 3879 7566 3857 7574 

HAIL...0.75IN
WIND...60MPH
 
$$

MPS
2 follow-up statements
361 
WWUS51 KPHI 072306
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
706 PM EDT Wed Aug 7 2019

MDC011-072315-
/O.CAN.KPHI.SV.W.0345.000000T0000Z-190807T2330Z/
Caroline MD-
706 PM EDT Wed Aug 7 2019

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

The storms which prompted the warning have moved out of the warned 
area. Therefore, the warning has been cancelled.

A severe thunderstorm watch remains in effect until 900 PM EDT for
central and southern Delaware...and eastern Maryland.

LAT...LON 3865 7571 3879 7561 3903 7543 3904 7536
      3900 7533 3893 7532 3883 7521 3879 7521
      3856 7536 3854 7570
TIME...MOT...LOC 2305Z 276DEG 14KT 3897 7539 3879 7552 3855 7568 

$$

DEC001-005-072330-
/O.CON.KPHI.SV.W.0345.000000T0000Z-190807T2330Z/
Sussex DE-Kent DE-
706 PM EDT Wed Aug 7 2019

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 730 PM EDT
FOR CENTRAL SUSSEX AND SOUTHEASTERN KENT COUNTIES...

At 705 PM EDT, severe thunderstorms were located along a line
extending from near Big Stone Beach to near Ellendale to near
Sharptown, moving east at 15 mph.

HAZARD...60 mph wind gusts and penny size hail.

SOURCE...Radar indicated.

IMPACT...Damage to roofs, siding, trees, and power lines is 
         possible.

Locations impacted include...
Georgetown, Milford, Seaford, Laurel, Milton, Bridgeville, Ellendale,
Sycamore, Blades, Greenwood, Houston and Bethel.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

To report severe weather contact your nearest law enforcement agency.
They will send your report to the National Weather Service office in
Mount Holly NJ.

Continuous cloud to ground lightning is occurring with these storms.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.

Torrential rainfall is occurring with these storms, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3865 7571 3879 7561 3903 7543 3904 7536
      3900 7533 3893 7532 3883 7521 3879 7521
      3856 7536 3854 7570
TIME...MOT...LOC 2305Z 276DEG 14KT 3897 7539 3879 7552 3855 7568 

HAIL...0.75IN
WIND...60MPH
 
$$

MPS
110 
WWUS51 KPHI 072322
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
722 PM EDT Wed Aug 7 2019

DEC001-005-072332-
/O.EXP.KPHI.SV.W.0345.000000T0000Z-190807T2330Z/
Sussex DE-Kent DE-
722 PM EDT Wed Aug 7 2019

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL SUSSEX AND
SOUTHEASTERN KENT COUNTIES WILL EXPIRE AT 730 PM EDT...
            
The storms which prompted the warning have weakened below severe
limits, and no longer pose an immediate threat to life or property.
Therefore, the warning will be allowed to expire.  However gusty
winds and heavy rain are still possible with these thunderstorms.

A severe thunderstorm watch remains in effect until 900 PM EDT for
central and southern Delaware...and eastern Maryland.

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
Mount Holly NJ.

LAT...LON 3865 7571 3879 7561 3903 7543 3904 7536
      3900 7533 3893 7532 3883 7521 3879 7521
      3856 7536 3854 7570
TIME...MOT...LOC 2322Z 255DEG 27KT 3900 7524 3882 7537 3858 7553 

$$

MPS

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 7, 10:02 AM EDTFlash Flood WatchPHINew Castle11 hr
Aug 7, 1:46 PM EDTSpecial Weather StatementPHISussex29 min
Aug 7, 1:49 PM EDTSevere Thunderstorm WarningPHISussex41 min
Aug 7, 4:27 PM EDTSevere Thunderstorm WarningPHINew Castle63 min
Aug 7, 4:44 PM EDTSpecial Weather StatementPHINew Castle31 min
Aug 7, 4:57 PM EDTSevere Thunderstorm WarningPHIKent, New Castle63 min
Aug 7, 5:16 PM EDTSevere Thunderstorm WarningPHINew Castle59 min
Aug 7, 5:33 PM EDTSevere Thunderstorm WarningPHIKent, New Castle42 min
Aug 7, 5:53 PM EDTSevere Thunderstorm WarningPHIKent, Sussex52 min
Aug 7, 6:01 PM EDTAreal Flood AdvisoryPHINew Castle3 hr
Aug 7, 7:23 PM EDTSpecial Weather StatementPHISussex37 min
Aug 7, 7:54 PM EDTSpecial Weather StatementPHISussex36 min
Aug 6, 10:29 PM EDTSpecial Weather StatementPHITalbot46 min
Aug 7, 4:07 PM EDTSevere Thunderstorm WarningPHICecil, Kent, Queen Anne's53 min

Nearby

Severe Thunderstorm Warnings in Delaware, 2019Severe Thunderstorm Warnings in Maryland, 2019Every severe thunderstorm warning in 2019

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.