Alert archive / Delaware / Special Weather Statements in 2021

Special Weather Statement, NWS Philadelphia/Mount Holly

July 28, 2021Sussex County, Delaware

NWS Philadelphia/Mount Holly issued this special weather statement at Jul 28, 2021, 4:20 PM EDT for Sussex County, Delaware. It was in force for 40 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 28, 2021, 4:20 PM EDT (20:20 UTC)
Expired
Jul 28, 2021, 5:00 PM EDT
In force
40 min
Issued by
NWS Philadelphia/Mount Holly

County Sussex County, DE

The radar

The Dover AFB radar (KDOX), 9 km from the middle of the area, began a volume at 20:20 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 nearest sounding before it

Wallops Is Stn, VA (KWAL), launched 12:00Z, 8.3 hours before the alert went out and 107 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 2021-07-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2437 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°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 2021-07-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -13 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
2437 J/kg
Mixed-layer CIN
-22 J/kg
Mixed-layer LCL
1072 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
-13 m²/s²
0-3 km storm-relative helicity
-3 m²/s²
Significant tornado parameter
-0.1
Supercell composite
-1.1

Open this sounding in Storm Lab

The text

As transmitted.

233 
WWUS81 KPHI 282020
SPSPHI

Special Weather Statement
National Weather Service Mount Holly NJ
420 PM EDT Wed Jul 28 2021

DEZ002-003-282100-
Inland Sussex-Kent-
420 PM EDT Wed Jul 28 2021

...A STRONG THUNDERSTORM WILL AFFECT NORTHEASTERN SUSSEX AND
SOUTHEASTERN KENT COUNTIES...

At 419 PM EDT, a strong thunderstorm was located near Milford, or 15
miles southeast of Dover, moving southeast at 15 mph.

Locations impacted include...
Georgetown, Milford, Lewes, Milton, Ellendale, Big Stone Beach,
Frederica and Houston.

If outdoors, consider seeking shelter inside a building.

Torrential rainfall is also occurring with this storm, and may cause
localized flooding. Do not drive your vehicle through flooded
roadways. Gusty winds, up to 30 mph are also possible. 

LAT...LON 3897 7555 3906 7536 3881 7509 3867 7538
TIME...MOT...LOC 2019Z 328DEG 14KT 3896 7541 

$$

PO

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 27, 10:44 PM EDTSpecial Weather StatementPHIWarren31 min
Jul 27, 11:13 PM EDTSpecial Weather StatementPHIWarren47 min
Jul 28, 3:53 PM EDTSpecial Weather StatementPHICape May22 min
Jul 27, 8:06 PM EDTSpecial Weather StatementPHIMonroe24 min
Jul 27, 10:22 PM EDTSpecial Weather StatementPHIMonroe23 min
Jul 27, 10:42 PM EDTSpecial Weather StatementPHICarbon33 min
Jul 28, 6:25 PM EDTSpecial Weather StatementPHIKent35 min

Nearby

Special Weather Statements in Delaware, 2021Every special weather statement in 2021

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.