Alert archive / Delaware / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 33, NWS Philadelphia/Mount Holly

April 13, 2020Kent County, Sussex County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Apr 13, 2020, 3:22 PM EDT for Kent County, Sussex County, Delaware. It was in force for 38 min. 7 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: Apr 13, 2020, 3:22 PM EDT (19:22 UTC)
Expired: Apr 13, 2020, 4:00 PM EDT
In force: 38 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Tornado: Possible
Hail: 0.75 in
Wind: 70.0 mph

Counties Kent County, DE, Sussex County, DE

The radar

The Dover AFB radar (KDOX), 36 km from the middle of the area, began a volume at 19:22 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
Apr 13, 3:30 PM EDT	TSTM WND DMG	4 Ese Sandtown, DE	DOWNED TREES AND WIRES. TIME BASED ON INITIAL REPORT FROM THE UTILITY COMPANY.
Apr 13, 3:45 PM EDT	TSTM WND DMG	1 Ese Woodside, DE	DOWNED TREES AND WIRES FROM SEVERE STORM WIND GUSTS. TIME BASED ON INITIAL REPORT FROM THE UTILITY COMPANY.
Apr 13, 3:49 PM EDT	TSTM WND GST 64	Dover Afb (Kdov), DE	DELAYED REPORT.
Apr 13, 3:50 PM EDT	TSTM WND DMG	3 Nne Magnolia, DE	DOWNED TREE ON STATE HIGHWAY 1 JUST SOUTH OF DOVER AFB. TIME ESTIMATED BASED ON RADAR AND NEARBY REPORTS.
Apr 13, 3:50 PM EDT	TSTM WND GST 79	1 Ne Magnolia, DE	DEDOT GAUGE.
Apr 13, 3:55 PM EDT	TSTM WND DMG	Milford, DE	SEVERAL REPORTS OF DOWNED TREES AND POWER LINES NEAR MILFORD. TIME ESTIMATED BASED ON RADAR AND UTILITY COMPANY REPORTS.
Apr 13, 3:55 PM EDT	TSTM WND GST 68	2 Wsw Kitts Hummock, DE	MEASURED 68 MPH GUST AT KITTS HUMMOCK (DE030).

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

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Apr 13, 11:33 AM EDT	Tornado Watch	SPC	5 hr

The nearest sounding before it

Wallops Is Stn, VA (KWAL), launched 12:00Z, 7.4 hours before the alert went out and 135 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: 1 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 702 m above ground
0-6 km bulk shear: 83 kt
0-1 km storm-relative helicity: 570 m²/s²
0-3 km storm-relative helicity: 696 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.6

Open this sounding in Storm Lab

The text

As transmitted.

307 
WUUS51 KPHI 131922
SVRPHI
DEC001-005-132000-
/O.NEW.KPHI.SV.W.0033.200413T1922Z-200413T2000Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
322 PM EDT Mon Apr 13 2020

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Northern Sussex County in southern Delaware...
  Kent County in central Delaware...

* Until 400 PM EDT.

* At 321 PM EDT, severe thunderstorms were located along a line
  extending from Bohemias Mills to near Sudlersville to near
  Grasonville, moving east at 55 mph.

  HAZARD...70 mph wind gusts and penny size hail.

  SOURCE...Radar and surface observations. Several gusts of 60 to 70 
           mph have been reported in eastern Maryland as these 
           storms have moved through.

  IMPACT...Expect considerable tree damage. Damage is likely to 
           mobile homes, roofs, and outbuildings.

* Locations impacted include...
  Dover, Smyrna, Milford, Harrington, Camden, Clayton, Lewes, Milton,
  Cheswold, Ellendale, Bowers, Woodside, Viola, Hartly, Rising
  Sun-Lebanon, Woodland Beach, Hazlettville, Dover Base Housing,
  Dover Speedway and Sandtown.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 600 PM EDT for central,
northern and southern Delaware...and eastern and northeastern
Maryland.

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

Intense thunderstorm lines can produce brief tornadoes and widespread
significant wind damage. Although a tornado is not immediately
likely, it is best to move to an interior room on the lowest floor of
a building. These storms may cause serious injury and significant
property damage.

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

&&

LAT...LON 3878 7572 3929 7576 3929 7565 3931 7558
      3935 7555 3935 7554 3938 7548 3928 7540
      3899 7530 3876 7505
TIME...MOT...LOC 1921Z 262DEG 47KT 3945 7579 3912 7582 3892 7621 

TORNADO...POSSIBLE
HAIL...0.75IN
WIND...70MPH
 
$$

CMS

2 follow-up statements

763 
WWUS51 KPHI 131951
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
351 PM EDT Mon Apr 13 2020

DEC001-005-132000-
/O.CON.KPHI.SV.W.0033.000000T0000Z-200413T2000Z/
Sussex DE-Kent DE-
351 PM EDT Mon Apr 13 2020

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 400 PM EDT
FOR NORTHERN SUSSEX AND KENT COUNTIES...

At 351 PM EDT, severe thunderstorms were located along a line
extending from near Greenwich to Bowers to near Denton, moving east
at 45 mph.

HAZARD...70 mph wind gusts and penny size hail.

SOURCE...Radar indicated.

IMPACT...Expect considerable tree damage. Damage is likely to mobile 
         homes, roofs, and outbuildings.

Locations impacted include...
Dover, Milford, Harrington, Camden, Lewes, Milton, Ellendale, Bowers,
Woodside, Viola, Rising Sun-Lebanon, Woodland Beach, Dover Base
Housing, Sandtown, Andrewsville, Rising Sun, Big Stone Beach,
Wyoming, Felton and Greenwood.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 600 PM EDT for central and
southern Delaware...and eastern Maryland.

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

Intense thunderstorm lines can produce brief tornadoes and widespread
significant wind damage. Although a tornado is not immediately
likely, it is best to move to an interior room on the lowest floor of
a building. These storms may cause serious injury and significant
property damage.

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

&&

LAT...LON 3878 7572 3907 7574 3916 7553 3938 7548
      3927 7540 3898 7529 3876 7506
TIME...MOT...LOC 1951Z 268DEG 39KT 3938 7540 3905 7543 3885 7582 

TORNADO...POSSIBLE
HAIL...0.75IN
WIND...70MPH
 
$$

CMS

329 
WWUS51 KPHI 131957
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
357 PM EDT Mon Apr 13 2020

DEC001-005-132007-
/O.EXP.KPHI.SV.W.0033.000000T0000Z-200413T2000Z/
Sussex DE-Kent DE-
357 PM EDT Mon Apr 13 2020

...THE SEVERE THUNDERSTORM WARNING FOR NORTHERN SUSSEX AND KENT
COUNTIES WILL EXPIRE AT 400 PM EDT...
            
The storms which prompted the warning have weakened below severe
limits, and no longer pose 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 these thunderstorms.

A Tornado Watch remains in effect until 600 PM EDT for central and
southern Delaware...and eastern Maryland.

LAT...LON 3878 7572 3907 7574 3916 7553 3938 7548
      3927 7540 3898 7529 3876 7506
TIME...MOT...LOC 1957Z 262DEG 47KT 3939 7532 3906 7536 3886 7575 

$$

CMS

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 13, 3:43 AM EDT	Coastal Flood Statement	PHI	Sussex	17 hr
Apr 13, 5:12 AM EDT	Special Weather Statement	PHI	Kent, New Castle	33 min
Apr 13, 5:41 AM EDT	Special Weather Statement	PHI	New Castle	34 min
Apr 13, 5:44 AM EDT	Special Weather Statement	PHI	Kent, Sussex	31 min
Apr 13, 6:11 AM EDT	Areal Flood Advisory	PHI	New Castle	4 hr
Apr 13, 6:17 AM EDT	Special Weather Statement	PHI	Kent, New Castle	28 min
Apr 13, 6:42 AM EDT	Areal Flood Advisory	PHI	Kent, New Castle	4 hr
Apr 13, 6:48 AM EDT	Areal Flood Advisory	PHI	New Castle	4 hr
Apr 13, 11:25 AM EDT	River Flood Warning	PHI	New Castle	4 hr
Apr 13, 12:13 PM EDT	River Flood Warning	PHI	New Castle	3 hr
Apr 13, 2:41 PM EDT	Severe Thunderstorm Warning	PHI	New Castle	64 min
Apr 13, 3:26 PM EDT	Tornado Warning	PHI	Kent	13 min
Apr 13, 3:40 PM EDT	Severe Thunderstorm Warning	PHI	Kent	65 min
Apr 13, 3:45 PM EDT	Tornado Warning	PHI	Kent	15 min

Nearby

Severe Thunderstorm Warnings in Delaware, 2020 Every severe thunderstorm warning in 2020

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.