Alert archive / Delaware / Special Weather Statements in 2021

Special Weather Statement, NWS Philadelphia/Mount Holly

August 13, 2021Sussex County, Delaware

NWS Philadelphia/Mount Holly issued this special weather statement at Aug 13, 2021, 8:04 PM EDT for Sussex County, Delaware. It was in force for 41 min. 6 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 13, 2021, 8:04 PM EDT (00:04 UTC)
Expired: Aug 13, 2021, 8:45 PM EDT
In force: 41 min
Issued by: NWS Philadelphia/Mount Holly
Hail: 0.25 in
Wind: 40

County Sussex County, DE

The radar

The Dover AFB radar (KDOX), 30 km from the middle of the area, began a volume at 00:08 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 13, 8:06 PM EDT	TSTM WND DMG	Greenwood, DE	TREES DOWN IN GREENWOOD, TIME ESTIMATED FROM RADAR.
Aug 13, 8:12 PM EDT	TSTM WND DMG	Bridgeville, DE	CORRECTS PREVIOUS TSTM WND DMG REPORT FROM BRIDGEVILLE. A COMMERCIAL OUT BUILDING HAD SIGNIFICANT DAMAGE. THE ROOF WAS BLOWN OFF, AND PORTIONS OF THE EXTERIOR WALLS WERE BLOWN DOWN. THIS WAS LIKELY DUE TO A DOWNBURST WITH ESTIMATED WIND SPEEDS OF 70 TO 80 MPH.
Aug 13, 8:12 PM EDT	TSTM WND DMG	Bridgeville, DE	CORRECTS PREVIOUS TSTM WND DMG REPORT FROM BRIDGEVILLE. SIX LARGE TRANSMISSION POLES WERE KNOCKED DOWN NEAR RAILROAD AVE.
Aug 13, 8:12 PM EDT	TSTM WND DMG	Bridgeville, DE	FOUR UTILITY POLES WERE KNOCKED DOWN ALONG THE RAILROAD TRACKS NEAR MARKET STREET AND SOUTH RAILROAD AVENUE.
Aug 13, 8:12 PM EDT	TSTM WND DMG	Bridgeville, DE	ROOF DAMAGE TO A COMMERCIAL BUILDING. TIME ESTIMATED FROM RADAR.
Aug 13, 8:12 PM EDT	TSTM WND DMG	Bridgeville, DE	TREE DOWN ON ROADWAY.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Wallops Is Stn, VA (KWAL), launched 00:00Z, 0.1 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: 2917 J/kg
Mixed-layer CIN: -55 J/kg
Mixed-layer LCL: 1083 m above ground
0-6 km bulk shear: 7 kt
0-1 km storm-relative helicity: 29 m²/s²
0-3 km storm-relative helicity: 46 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

298 
WWUS81 KPHI 140004
SPSPHI

Special Weather Statement
National Weather Service Mount Holly NJ
804 PM EDT Fri Aug 13 2021
 
DEZ003-MDZ020-140045-
Inland Sussex DE-Caroline MD-
804 PM EDT Fri Aug 13 2021

...A strong thunderstorm will impact portions of southwestern Sussex
and southeastern Caroline Counties through 845 PM EDT...

At 804 PM EDT, Doppler radar was tracking a strong thunderstorm near
Seaford, or 12 miles east of Hurlock, moving southeast at 25 mph.

HAZARD...Winds in excess of 40 mph and pea size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around 
         unsecured objects. Minor damage to outdoor objects is 
         possible.

Locations impacted include...
Georgetown, Seaford, Millsboro, Laurel, Federalsburg, Bridgeville,
Delmar, Smithville, Gumboro, Sycamore, Blades, Greenwood and Bethel.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building. 

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

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 3846 7569 3849 7570 3864 7571 3869 7577
      3868 7578 3868 7580 3869 7580 3870 7583
      3883 7567 3875 7521 3845 7537
TIME...MOT...LOC 0004Z 298DEG 21KT 3869 7566 

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...40 MPH

$$

NC

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 13, 9:26 PM EDT	Special Marine Warning	PHI		64 min
Aug 13, 8:28 PM EDT	Special Weather Statement	PHI	Sussex	62 min
Aug 13, 8:40 PM EDT	Areal Flood Advisory	PHI	Sussex	62 min

Nearby

Special Weather Statements in Delaware, 2021 Every 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.