Alert archive / Delaware / Severe Thunderstorm Warnings in 2023

Severe Thunderstorm Warning 333, NWS Philadelphia/Mount Holly

September 8, 2023Sussex County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Sep 8, 2023, 3:32 PM EDT for Sussex County, Delaware. It was in force for 43 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
Sep 8, 2023, 3:32 PM EDT (19:32 UTC)
Expired
Sep 8, 2023, 4:15 PM EDT
In force
43 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Hail
0.88 in
Wind
60.0 mph

County Sussex County, DE

The radar

The Dover AFB radar (KDOX), 23 km from the middle of the area, began a volume at 19:33 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
Sep 8, 3:11 PM EDTSevere Thunderstorm WatchSPC8 hr

The nearest sounding before it

Wallops Is Stn, VA (KWAL), launched 12:00Z, 7.5 hours before the alert went out and 80 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 2023-09-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2819 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 2023-09-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 12 square meters per square second.1939Sfc1 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
2819 J/kg
Mixed-layer CIN
-41 J/kg
Mixed-layer LCL
953 m above ground
0-6 km bulk shear
23 kt
0-1 km storm-relative helicity
12 m²/s²
0-3 km storm-relative helicity
50 m²/s²
Significant tornado parameter
0.5
Supercell composite
2.8

Open this sounding in Storm Lab

The text

As transmitted.

475 
WUUS51 KPHI 081932
SVRPHI
DEC005-082015-
/O.NEW.KPHI.SV.W.0333.230908T1932Z-230908T2015Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
332 PM EDT Fri Sep 8 2023

The National Weather Service in Mount Holly NJ has issued a

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

* Until 415 PM EDT.

* At 332 PM EDT, a severe thunderstorm was located near Millsboro, or
  near Georgetown, moving north at 15 mph.

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

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Georgetown, Millsboro, Lewes, Milton, Dagsboro, Ellendale,
  Sycamore, Long Neck and Frankford.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 3850 7523 3858 7554 3886 7545 3878 7508
TIME...MOT...LOC 1932Z 194DEG 11KT 3862 7536 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.88 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

MLB
2 follow-up statements
189 
WWUS51 KPHI 081952
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
352 PM EDT Fri Sep 8 2023

DEC005-082015-
/O.CON.KPHI.SV.W.0333.000000T0000Z-230908T2015Z/
Sussex DE-
352 PM EDT Fri Sep 8 2023

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 415 PM EDT
FOR CENTRAL SUSSEX COUNTY...

At 351 PM EDT, a severe thunderstorm was located near Georgetown,
moving north at 10 mph.

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

SOURCE...Radar indicated.

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

Locations impacted include...
Georgetown, Millsboro, Lewes, Milton, Dagsboro, Ellendale, Sycamore,
Long Neck and Frankford.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 3850 7523 3858 7554 3886 7545 3878 7508
TIME...MOT...LOC 1951Z 192DEG 9KT 3865 7536 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.88 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

MLB
593 
WWUS51 KPHI 082011
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
411 PM EDT Fri Sep 8 2023

DEC005-082020-
/O.EXP.KPHI.SV.W.0333.000000T0000Z-230908T2015Z/
Sussex DE-
411 PM EDT Fri Sep 8 2023

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL SUSSEX COUNTY WILL
EXPIRE AT 415 PM EDT...
                
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 will be allowed to expire.  However gusty
winds and heavy rain are still possible with this thunderstorm.

A Severe Thunderstorm Watch remains in effect until 1100 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 3850 7523 3858 7554 3886 7545 3878 7508
TIME...MOT...LOC 2010Z 194DEG 11KT 3870 7535 

$$

MLB

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 7, 9:14 PM EDTSevere Thunderstorm WarningPHIKent30 min
Sep 8, 1:21 PM EDTSpecial Weather StatementPHISussex24 min
Sep 8, 1:51 PM EDTSpecial Weather StatementPHISussex24 min
Sep 8, 2:05 PM EDTSevere Thunderstorm WarningPHIKent, Sussex40 min
Sep 8, 2:15 PM EDTSevere Thunderstorm WarningPHIKent45 min
Sep 8, 2:46 PM EDTSpecial Weather StatementPHIKent29 min
Sep 8, 2:51 PM EDTSevere Thunderstorm WarningPHIKent39 min
Sep 8, 3:27 PM EDTSpecial Weather StatementPHIKent, New Castle33 min
Sep 8, 3:31 PM EDTSevere Thunderstorm WarningPHIKent, New Castle44 min

Nearby

Severe Thunderstorm Warnings in Delaware, 2023Every severe thunderstorm warning in 2023

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.