Alert archive / Delaware / Severe Thunderstorm Warnings in 2019

Severe Thunderstorm Warning 299, NWS Philadelphia/Mount Holly

July 31, 2019Sussex County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 31, 2019, 6:05 PM EDT for Sussex County, Delaware. It was in force for 26 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 31, 2019, 6:05 PM EDT (22:05 UTC)
Expired: Jul 31, 2019, 6:31 PM EDT
In force: 26 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

County Sussex County, DE

The radar

The Dover AFB radar (KDOX), 34 km from the middle of the area, began a volume at 22:07 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
Jul 31, 1:17 PM EDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Wallops Is Stn, VA (KWAL), launched 12:00Z, 10.1 hours before the alert went out and 81 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: 80 J/kg
Mixed-layer CIN: -82 J/kg
Mixed-layer LCL: 1478 m above ground
0-6 km bulk shear: 23 kt
0-1 km storm-relative helicity: 48 m²/s²
0-3 km storm-relative helicity: 41 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.4

Open this sounding in Storm Lab

The text

As transmitted.

393 
WUUS51 KPHI 312205
SVRPHI
DEC005-312245-
/O.NEW.KPHI.SV.W.0299.190731T2205Z-190731T2245Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
605 PM EDT Wed Jul 31 2019

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Southeastern Sussex County in southern Delaware...

* Until 645 PM EDT.

* At 604 PM EDT, a severe thunderstorm was located near Millsboro, or
  9 miles southeast of Georgetown, moving east at 20 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...
  Millsboro, Dagsboro, Millville, Henlopen Acres, Long Neck, Ocean
  View, Frankford, South Bethany and Dewey Beach.

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.

&&

LAT...LON 3869 7534 3874 7508 3867 7507 3869 7508
      3869 7514 3864 7513 3862 7508 3866 7507
      3861 7506 3859 7521 3857 7518 3859 7514
      3858 7507 3860 7509 3860 7506 3852 7505
      3851 7531
TIME...MOT...LOC 2204Z 261DEG 16KT 3861 7524 

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

MPS

1 follow-up statement

327 
WWUS51 KPHI 312231
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
631 PM EDT Wed Jul 31 2019

DEC005-312241-
/O.CAN.KPHI.SV.W.0299.000000T0000Z-190731T2245Z/
Sussex DE-
631 PM EDT Wed Jul 31 2019

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN SUSSEX COUNTY IS
CANCELLED...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning has been cancelled.

A severe thunderstorm watch remains in effect until 900 PM EDT for
southern Delaware.

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 3869 7534 3874 7508 3867 7507 3869 7508
      3869 7514 3864 7513 3862 7508 3866 7507
      3861 7506 3859 7521 3857 7518 3859 7514
      3858 7507 3860 7509 3860 7506 3852 7505
      3851 7531
TIME...MOT...LOC 2231Z 261DEG 16KT 3863 7509 

$$

MPS

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 31, 3:28 AM EDT	Flash Flood Watch	PHI	New Castle	17 hr
Jul 31, 2:46 PM EDT	Severe Thunderstorm Warning	PHI	New Castle	44 min
Jul 31, 4:00 PM EDT	Special Weather Statement	PHI	Sussex	30 min
Jul 31, 4:33 PM EDT	Severe Thunderstorm Warning	PHI	Sussex	9 min

Nearby

Severe Thunderstorm Warnings in Delaware, 2019 Every 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.