Alert archive / Delaware / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 266, NWS Philadelphia/Mount Holly

August 23, 2021Kent County, New Castle County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 23, 2021, 7:14 PM EDT for Kent County, New Castle County, Delaware. It was in force for 31 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
Aug 23, 2021, 7:14 PM EDT (23:14 UTC)
Expired
Aug 23, 2021, 7:45 PM EDT
In force
31 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Kent County, DE, New Castle County, DE

The radar

The Dover AFB radar (KDOX), 55 km from the middle of the area, began a volume at 23:14 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, 11.2 hours before the alert went out and 153 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 2021-08-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1 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 2021-08-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 16 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
1 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1488 m above ground
0-6 km bulk shear
13 kt
0-1 km storm-relative helicity
16 m²/s²
0-3 km storm-relative helicity
45 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

600 
WUUS51 KPHI 232314
SVRPHI
DEC001-003-240000-
/O.NEW.KPHI.SV.W.0266.210823T2314Z-210824T0000Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
714 PM EDT Mon Aug 23 2021

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Southwestern New Castle County in northern Delaware...
  Northern Kent County in central Delaware...

* Until 800 PM EDT.

* At 714 PM EDT, a severe thunderstorm was located over Green Spring,
  or 8 miles south of Middletown, moving southeast at 25 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Dover, Middletown, Smyrna, Camden, Clayton, Cheswold, Woodside,
  Hartly, Rising Sun-Lebanon, Hazlettville, Delaney Corner, Dover
  Base Housing, Dover Speedway, Green Spring, Rising Sun, Townsend,
  Wyoming, Odessa, Kenton and Little Creek.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3947 7565 3917 7534 3900 7568 3922 7576
      3942 7577
TIME...MOT...LOC 2314Z 327DEG 23KT 3933 7569 

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

$$

Davis
2 follow-up statements
671 
WWUS51 KPHI 232329
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
729 PM EDT Mon Aug 23 2021

DEC003-232338-
/O.CAN.KPHI.SV.W.0266.000000T0000Z-210824T0000Z/
New Castle DE-
729 PM EDT Mon Aug 23 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHWESTERN NEW CASTLE COUNTY
IS CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

LAT...LON 3930 7569 3929 7565 3931 7562 3931 7558
      3934 7555 3935 7556 3935 7553 3917 7534
      3900 7568 3920 7576 3929 7576
TIME...MOT...LOC 2328Z 327DEG 23KT 3925 7562 

$$

DEC001-240000-
/O.CON.KPHI.SV.W.0266.000000T0000Z-210824T0000Z/
Kent DE-
729 PM EDT Mon Aug 23 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 800 PM EDT
FOR NORTHERN KENT COUNTY...

At 728 PM EDT, a severe thunderstorm was located over Smyrna, or 8
miles northwest of Dover, moving southeast at 25 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
Dover, Smyrna, Camden, Clayton, Cheswold, Woodside, Hartly, Rising
Sun-Lebanon, Rising Sun, Hazlettville, Dover Base Housing, Dover
Speedway, Wyoming, Kenton, Little Creek, Leipsic, Rodney Village,
Kent Acres, Highland Acres and Woodside East.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3930 7569 3929 7565 3931 7562 3931 7558
      3934 7555 3935 7556 3935 7553 3917 7534
      3900 7568 3920 7576 3929 7576
TIME...MOT...LOC 2328Z 327DEG 23KT 3925 7562 

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

$$

Davis
004 
WWUS51 KPHI 232345
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
745 PM EDT Mon Aug 23 2021

DEC001-232354-
/O.CAN.KPHI.SV.W.0266.000000T0000Z-210824T0000Z/
Kent DE-
745 PM EDT Mon Aug 23 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHERN KENT COUNTY IS
CANCELLED...
                
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 has been cancelled.  However gusty winds are
still possible with this thunderstorm.

LAT...LON 3930 7569 3929 7565 3931 7562 3931 7558
      3934 7555 3935 7556 3935 7553 3917 7534
      3900 7568 3920 7576 3929 7576
TIME...MOT...LOC 2343Z 327DEG 23KT 3916 7554 

$$

Davis

Nearby

Severe Thunderstorm Warnings in Delaware, 2021Every severe thunderstorm warning 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.