Alert archive / Maryland / Severe Thunderstorm Warnings in 2019

Severe Thunderstorm Warning 245, NWS Philadelphia/Mount Holly

July 21, 2019New Castle County, Delaware; Cecil County, Kent County, Maryland

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 21, 2019, 9:44 PM EDT for New Castle County, Delaware; Cecil County, Kent County, Maryland. It was in force for 46 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 21, 2019, 9:44 PM EDT (01:44 UTC)
Expired
Jul 21, 2019, 10:30 PM EDT
In force
46 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties New Castle County, DE, Cecil County, MD, Kent County, MD

The radar

The Dover AFB radar (KDOX), 76 km from the middle of the area, began a volume at 01:46 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 150 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 2019-07-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 157 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 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 2019-07-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -73 square meters per square second.1939Sfc1 km3 km6 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
157 J/kg
Mixed-layer CIN
-308 J/kg
Mixed-layer LCL
1994 m above ground
0-6 km bulk shear
14 kt
0-1 km storm-relative helicity
-73 m²/s²
0-3 km storm-relative helicity
-77 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

913 
WUUS51 KPHI 220144
SVRPHI
DEC003-MDC015-029-220230-
/O.NEW.KPHI.SV.W.0245.190722T0144Z-190722T0230Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
944 PM EDT Sun Jul 21 2019

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Southwestern New Castle County in northern Delaware...
  Northeastern Kent County in northeastern Maryland...
  Southeastern Cecil County in northeastern Maryland...

* Until 1030 PM EDT.

* At 944 PM EDT, a severe thunderstorm was located near Cecilton, or
  10 miles east of Aberdeen Proving Ground, moving east at 30 mph.

  HAZARD...60 mph wind gusts and quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Minor damage to vehicles is possible. Wind damage to 
           roofs, siding, trees, and power lines is possible.

* Locations impacted include...
  Middletown, Delaware City, Cecilton, Betterton, Warwick, Saint
  Georges, Sassafras, Mount Pleasant, Bohemias Mills, Port Penn,
  Brantwood, Cayots, Hollywood Beach, Townsend, Chesapeake City,
  Galena, Odessa and Chambersville.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 3937 7611 3937 7606 3942 7600 3950 7599
      3962 7561 3959 7560 3959 7557 3958 7558
      3951 7556 3949 7559 3946 7559 3941 7554
      3936 7552 3931 7604 3935 7613
TIME...MOT...LOC 0144Z 251DEG 24KT 3942 7595 

HAIL...1.00IN
WIND...60MPH
 
$$

Staarmann
1 follow-up statement
023 
WWUS51 KPHI 220203
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
1003 PM EDT Sun Jul 21 2019

MDC029-220213-
/O.CAN.KPHI.SV.W.0245.000000T0000Z-190722T0230Z/
Kent MD-
1003 PM EDT Sun Jul 21 2019

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN KENT 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 3947 7597 3962 7562 3959 7560 3959 7557
      3958 7558 3952 7557 3951 7556 3950 7559
      3946 7559 3938 7553 3938 7582 3937 7583
      3937 7595 3942 7600
TIME...MOT...LOC 0203Z 240DEG 14KT 3943 7588 

$$

DEC003-MDC015-220230-
/O.CON.KPHI.SV.W.0245.000000T0000Z-190722T0230Z/
New Castle DE-Cecil MD-
1003 PM EDT Sun Jul 21 2019

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1030 PM EDT
FOR SOUTHWESTERN NEW CASTLE AND SOUTHEASTERN CECIL COUNTIES...

At 1003 PM EDT, a severe thunderstorm was located over Cecilton, or 8
miles west of Middletown, moving northeast at 15 mph.

HAZARD...60 mph wind gusts and quarter size hail.

SOURCE...Radar indicated.

IMPACT...Minor damage to vehicles is possible. Wind damage to roofs, 
         siding, trees, and power lines is possible.

Locations impacted include...
Middletown, Delaware City, Cecilton, Warwick, Saint Georges, Port
Penn, Mount Pleasant, Cayots, Bohemias Mills, Townsend, Chesapeake
City and Odessa.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 3947 7597 3962 7562 3959 7560 3959 7557
      3958 7558 3952 7557 3951 7556 3950 7559
      3946 7559 3938 7553 3938 7582 3937 7583
      3937 7595 3942 7600
TIME...MOT...LOC 0203Z 240DEG 14KT 3943 7588 

HAIL...1.00IN
WIND...60MPH
 
$$

Staarmann

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 21, 9:30 PM EDTSevere Thunderstorm WarningPHINew Castle45 min
Jul 21, 10:13 PM EDTSevere Thunderstorm WarningPHINew Castle47 min
Jul 21, 10:54 PM EDTSevere Thunderstorm WarningPHINew Castle25 min
Jul 22, 3:47 PM EDTSevere Thunderstorm WarningPHINew Castle58 min
Jul 22, 4:16 PM EDTSevere Thunderstorm WarningPHINew Castle59 min
Jul 22, 4:40 PM EDTAreal Flood AdvisoryPHIKent, New Castle114 min
Jul 22, 5:14 PM EDTSevere Thunderstorm WarningPHINew Castle61 min
Jul 21, 9:55 PM EDTAreal Flood AdvisoryPHICecil87 min
Jul 22, 4:11 PM EDTAreal Flood AdvisoryPHICecil4 hr
Jul 22, 4:21 PM EDTAreal Flood AdvisoryPHICecil, Kent2 hr

Nearby

Severe Thunderstorm Warnings in Maryland, 2019Severe Thunderstorm Warnings in Delaware, 2019Every severe thunderstorm warning in 2019

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.