Alert archive / Delaware / Severe Thunderstorm Warnings in 2026

Severe Thunderstorm Warning 303, NWS Philadelphia/Mount Holly

August 10, 2026Sussex County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 10, 2026, 7:04 PM EDT for Sussex County, Delaware. It was in force for 41 min. 3 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: Aug 10, 2026, 7:04 PM EDT (23:04 UTC)
Expired: Aug 10, 2026, 7:45 PM EDT
In force: 41 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), 32 km from the middle of the area, began a volume at 23:06 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

Time	Report	Where	Remark
Aug 10, 7:04 PM EDT	MARINE TSTM WIND 50	2 Nw Lewes, DE	Lewes YC - XLEW.
Aug 10, 7:06 PM EDT	TSTM WND DMG	1 W Millville, DE	Wires down. Time estimated from radar.
Aug 10, 7:09 PM EDT	TSTM WND GST 63	3 N Long Neck, DE	Measured via a PWS.

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.

Issued	Product	Office	Lasted
Aug 10, 2:10 PM EDT	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 11.1 hours before the alert went out and 198 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: 682 J/kg
Mixed-layer CIN: -91 J/kg
Mixed-layer LCL: 1254 m above ground
0-6 km bulk shear: 29 kt
0-1 km storm-relative helicity: -34 m²/s²
0-3 km storm-relative helicity: -2 m²/s²
Significant tornado parameter: -0.0
Supercell composite: -0.6

Open this sounding in Storm Lab

The text

As transmitted.

225 
WUUS51 KPHI 102304
SVRPHI
DEC005-102345-
/O.NEW.KPHI.SV.W.0303.260810T2304Z-260810T2345Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
704 PM EDT Mon Aug 10 2026

The National Weather Service in Mount Holly NJ has issued a

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

* Until 745 PM EDT.

* At 703 PM EDT, a severe thunderstorm was located near Henlopen
  Acres, or 13 miles east of Georgetown, moving southeast at 45 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Millsboro, Lewes, Dagsboro, Millville, Henlopen Acres, Cape
  Henlopen State Park, Long Neck, Ocean View, 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.

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

&&

LAT...LON 3859 7535 3883 7515 3882 7511 3880 7506
      3849 7501 3845 7502
TIME...MOT...LOC 2303Z 302DEG 38KT 3869 7515 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

MPS

1 follow-up statement

078 
WWUS51 KPHI 102336
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
736 PM EDT Mon Aug 10 2026

DEC005-102346-
/O.EXP.KPHI.SV.W.0303.000000T0000Z-260810T2345Z/
Sussex DE-
736 PM EDT Mon Aug 10 2026

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN SUSSEX COUNTY
WILL EXPIRE AT 745 PM EDT...

The storm which prompted the warning has moved out of the area.
Therefore, the warning will be allowed to expire.

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 3859 7535 3883 7515 3882 7511 3880 7506
      3849 7501 3845 7502
TIME...MOT...LOC 2336Z 302DEG 38KT 3854 7484 

$$

MPS

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 10, 4:39 PM EDT	Severe Thunderstorm Warning	PHI	New Castle	66 min
Aug 10, 4:46 PM EDT	Severe Thunderstorm Warning	PHI	New Castle	20 min
Aug 10, 5:36 PM EDT	Severe Thunderstorm Warning	PHI	Kent, New Castle, Sussex	39 min
Aug 10, 6:07 PM EDT	Severe Thunderstorm Warning	PHI	Kent, New Castle, Sussex	38 min
Aug 10, 6:22 PM EDT	Severe Thunderstorm Warning	PHI	Sussex	23 min

Nearby

Severe Thunderstorm Warnings in Delaware, 2026 Every severe thunderstorm warning in 2026

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.