Alert archive / Maryland / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 150, NWS Philadelphia/Mount Holly

July 21, 2020Caroline County, Kent County, Queen Anne's County, Maryland; Kent County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 21, 2020, 10:21 PM EDT for Caroline County, Kent County, Queen Anne's County, Maryland; Kent County, Delaware. It was in force for 54 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
Jul 21, 2020, 10:21 PM EDT (02:21 UTC)
Expired
Jul 21, 2020, 11:15 PM EDT
In force
54 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Kent County, DE, Caroline County, MD, Kent County, MD, Queen Anne's County, MD

The radar

The Dover AFB radar (KDOX), 51 km from the middle of the area, began a volume at 02:24 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

TimeReportWhereRemark
Jul 21, 10:23 PM EDTTSTM WND DMG1 Nnw Sudlersville, MDTWO TREES REPORTED DOWN BETWEEN SUDLERSVILLE AND CRUMPTON. TIME ESTIMATED FROM RADAR.
Jul 21, 10:23 PM EDTTSTM WND DMG1 Nnw Sudlersville, MDTWO TREES REPORTED DOWN BETWEEN SUDLERSVILLE AND CRUMPTON. TIME ESTIMATED FROM RADAR.
Jul 21, 10:30 PM EDTTSTM WND DMG2 Se Hartly, DESEVERAL REPORTS OF TREES AND WIRES DOWN NEAR CRYSTAL ROAD SOUTHEAST OF HARTLY. TIME ESTIMATED FROM RADAR.
Jul 21, 10:32 PM EDTTSTM WND DMG2 Se Hartly, DEDOWNED POWER POLE AND WIRES NEAR JUDITH ROAD NEAR HARTLY. TIME ESTIMATED FROM RADAR.
Jul 21, 11:14 PM EDTTSTM WND GST 433 Ssw Little Creek, DEKDOV MEASURED GUST.
Jul 21, 11:14 PM EDTMARINE TSTM WIND 433 Ssw Little Creek, DE

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, 2.4 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, Wallops Is Stn, VA at 00:00Z on 2020-07-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3628 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 00:00Z on 2020-07-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 61 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
3628 J/kg
Mixed-layer CIN
-33 J/kg
Mixed-layer LCL
1027 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
61 m²/s²
0-3 km storm-relative helicity
94 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

591 
WUUS51 KPHI 220221
SVRPHI
DEC001-MDC011-029-035-220315-
/O.NEW.KPHI.SV.W.0150.200722T0221Z-200722T0315Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
1021 PM EDT Tue Jul 21 2020

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Central Kent County in central Delaware...
  Northeastern Queen Anne's County in northeastern Maryland...
  Northeastern Caroline County in eastern Maryland...
  East central Kent County in northeastern Maryland...

* Until 1115 PM EDT.

* At 1021 PM EDT, a severe thunderstorm was located over
  Sudlersville, or 13 miles northeast of Centerville, moving east at
  20 mph.

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

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Dover, Smyrna, Camden, Clayton, Cheswold, Millington, Sudlersville,
  Bowers, Goldsboro, Woodside, Viola, Hartly, Rising Sun-Lebanon,
  Woodland Beach, Hazlettville, Dover Base Housing, Crumpton, Dover
  Speedway, Rising Sun and Wyoming.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

In addition to hail and damaging winds, frequent cloud to ground 
lightning is occurring with this storm. Move indoors immediately. 
Remember, if you can hear thunder, you are close enough to be struck 
by lightning.

&&

LAT...LON 3924 7597 3930 7568 3929 7565 3931 7562
      3931 7558 3932 7557 3935 7542 3904 7535
      3904 7591
TIME...MOT...LOC 0221Z 265DEG 18KT 3916 7586 

HAIL...0.75IN
WIND...60MPH
 
$$

Gorse
3 follow-up statements
291 
WWUS51 KPHI 220239
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
1039 PM EDT Tue Jul 21 2020

DEC001-MDC011-029-035-220315-
/O.CON.KPHI.SV.W.0150.000000T0000Z-200722T0315Z/
Kent DE-Queen Anne's MD-Caroline MD-Kent MD-
1039 PM EDT Tue Jul 21 2020

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1115 PM EDT
FOR CENTRAL KENT...NORTHEASTERN QUEEN ANNE'S...NORTHEASTERN CAROLINE
AND EAST CENTRAL KENT COUNTIES...

At 1038 PM EDT, a severe thunderstorm was located over Hartly, or 8
miles west of Dover, moving east at 30 mph.

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

SOURCE...Radar indicated.

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

Locations impacted include...
Dover, Smyrna, Camden, Clayton, Cheswold, Millington, Sudlersville,
Bowers, Goldsboro, Woodside, Viola, Hartly, Rising Sun-Lebanon,
Woodland Beach, Hazlettville, Dover Base Housing, Dover Speedway,
Rising Sun, Wyoming and Kenton.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Frequent cloud to ground lightning is occurring with this storm. Move
indoors immediately. Lightning is one of nature's leading killers.
Remember, if you can hear thunder, you are close enough to be struck
by lightning.

&&

LAT...LON 3930 7569 3929 7565 3931 7562 3931 7558
      3932 7557 3935 7542 3904 7535 3904 7586
      3926 7586
TIME...MOT...LOC 0238Z 265DEG 26KT 3917 7568 

HAIL...0.75IN
WIND...60MPH
 
$$

Gorse
014 
WWUS51 KPHI 220254
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
1054 PM EDT Tue Jul 21 2020

MDC011-029-035-220303-
/O.CAN.KPHI.SV.W.0150.000000T0000Z-200722T0315Z/
Queen Anne's MD-Caroline MD-Kent MD-
1054 PM EDT Tue Jul 21 2020

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN QUEEN ANNE'S...
NORTHEASTERN CAROLINE AND EAST CENTRAL KENT COUNTIES 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
      3932 7557 3935 7542 3904 7535 3904 7572
      3929 7573
TIME...MOT...LOC 0253Z 271DEG 21KT 3916 7555 

$$

DEC001-220315-
/O.CON.KPHI.SV.W.0150.000000T0000Z-200722T0315Z/
Kent DE-
1054 PM EDT Tue Jul 21 2020

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1115 PM EDT
FOR CENTRAL KENT COUNTY...

At 1053 PM EDT, a severe thunderstorm was located over Dover, moving
east at 25 mph.

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

SOURCE...Radar indicated.

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

Locations impacted include...
Dover, Smyrna, Camden, Clayton, Cheswold, Bowers, Woodside, Viola,
Hartly, Rising Sun-Lebanon, Woodland Beach, Rising Sun, Hazlettville,
Dover Base Housing, Dover Speedway, Wyoming, Kenton, Magnolia, Little
Creek and Leipsic.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Frequent cloud to ground lightning is occurring with this storm. Move
indoors immediately. Lightning is one of nature's leading killers.
Remember, if you can hear thunder, you are close enough to be struck
by lightning.

&&

LAT...LON 3930 7569 3929 7565 3931 7562 3931 7558
      3932 7557 3935 7542 3904 7535 3904 7572
      3929 7573
TIME...MOT...LOC 0253Z 271DEG 21KT 3916 7555 

HAIL...0.75IN
WIND...60MPH
 
$$

Gorse
979 
WWUS51 KPHI 220312
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
1112 PM EDT Tue Jul 21 2020

DEC001-220322-
/O.EXP.KPHI.SV.W.0150.000000T0000Z-200722T0315Z/
Kent DE-
1112 PM EDT Tue Jul 21 2020

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL KENT COUNTY WILL
EXPIRE AT 1115 PM EDT...
                
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 will be allowed to expire. However gusty 
winds are still possible with this thunderstorm.

LAT...LON 3930 7569 3929 7565 3931 7562 3931 7558
      3932 7557 3935 7542 3904 7535 3904 7572
      3929 7573
TIME...MOT...LOC 0312Z 265DEG 18KT 3917 7543 

$$

Gorse

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 21, 9:16 PM EDTSpecial Weather StatementPHIKent29 min
Jul 21, 9:25 PM EDTSpecial Weather StatementPHITalbot35 min
Jul 21, 9:39 PM EDTSevere Thunderstorm WarningPHICaroline, Talbot51 min
Jul 21, 9:46 PM EDTSpecial Weather StatementPHIKent, Queen Anne's29 min
Jul 21, 10:14 PM EDTSpecial Weather StatementPHICaroline46 min
Jul 22, 4:01 PM EDTSevere Thunderstorm WarningPHICecil22 min
Jul 22, 4:38 PM EDTSevere Thunderstorm WarningPHICecil52 min
Jul 22, 4:47 PM EDTSevere Thunderstorm WarningPHICaroline, Queen Anne's, Talbot43 min
Jul 22, 5:13 PM EDTSevere Thunderstorm WarningPHICecil, Kent, Queen Anne's47 min
Jul 22, 5:23 PM EDTSevere Thunderstorm WarningPHICaroline, Queen Anne's, Talbot52 min
Jul 22, 5:54 PM EDTSevere Thunderstorm WarningPHICaroline, Cecil, Kent, Queen Anne's51 min
Jul 22, 5:33 PM EDTSevere Thunderstorm WarningPHINew Castle57 min

Nearby

Severe Thunderstorm Warnings in Maryland, 2020Severe Thunderstorm Warnings in Delaware, 2020Every 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.