Alert archive / Delaware / Special Weather Statements in 2021

Special Weather Statement, NWS Philadelphia/Mount Holly

April 11, 2021New Castle County, Delaware

NWS Philadelphia/Mount Holly issued this special weather statement at Apr 11, 2021, 9:43 PM EDT for New Castle County, Delaware. It was in force for 47 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
Apr 11, 2021, 9:43 PM EDT (01:43 UTC)
Expired
Apr 11, 2021, 10:30 PM EDT
In force
47 min
Issued by
NWS Philadelphia/Mount Holly

County New Castle County, DE

The radar

The Dover AFB radar (KDOX), 74 km from the middle of the area, began a volume at 01:45 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

Washington/Dulle, VA (KIAD), launched 00:00Z, 1.7 hours before the alert went out and 148 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, Washington/Dulle, VA at 00:00Z on 2021-04-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 154 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, Washington/Dulle, VA at 00:00Z on 2021-04-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 57 square meters per square second.19395878Sfc1 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
154 J/kg
Mixed-layer CIN
-40 J/kg
Mixed-layer LCL
2014 m above ground
0-6 km bulk shear
12 kt
0-1 km storm-relative helicity
57 m²/s²
0-3 km storm-relative helicity
58 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

197 
WWUS81 KPHI 120143
SPSPHI

Special Weather Statement
National Weather Service Mount Holly NJ
943 PM EDT Sun Apr 11 2021

DEZ001-002-MDZ012-015-120230-
Kent-New Castle-Queen Anne's-Kent-
943 PM EDT Sun Apr 11 2021

...A STRONG THUNDERSTORM WILL AFFECT NEW CASTLE...NORTHWESTERN
KENT...NORTHEASTERN QUEEN ANNE'S AND NORTHEASTERN KENT COUNTIES...

At 943 PM EDT, a strong thunderstorm was located near Kennedyville,
or 12 miles southeast of Aberdeen Proving Ground, moving northeast at
35 mph.

Wind gusts up to 40 mph and pea size hail are possible with this
storm.

Locations impacted include...
Newark, Middletown, Clayton, Delaware City, Millington, Sudlersville,
Saint Georges, Sassafras, Mount Pleasant, Green Spring, Glasgow,
Bear, Port Penn, Morgnec, Delaney Corner, Pike Creek, Massey,
Crumpton, Kennedyville and North Star.

This includes Interstate 95 in Delaware between mile markers 1 and 8.
 
Torrential rainfall is also occurring with this storm, and may cause
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 3938 7606 3936 7589 3938 7582 3938 7577
      3971 7579 3976 7572 3956 7551 3954 7554
      3952 7553 3930 7564 3924 7574 3914 7595
      3933 7610
TIME...MOT...LOC 0143Z 212DEG 31KT 3935 7595 

$$

NC

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 12, 1:12 AM EDTAreal Flood AdvisoryPHIBurlington, Camden, Gloucester67 min
Apr 11, 9:13 PM EDTSpecial Weather StatementPHIKent32 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.