Alert archive / Maryland / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 98, NWS Philadelphia/Mount Holly

June 21, 20214 counties in Maryland; Kent County, New Castle County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jun 21, 2021, 6:47 PM EDT for 4 counties in Maryland; Kent County, New Castle County, Delaware. It was in force for 58 min. 9 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
Jun 21, 2021, 6:47 PM EDT (22:47 UTC)
Expired
Jun 21, 2021, 7:45 PM EDT
In force
58 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, Caroline County, MD, Kent County, MD, Queen Anne's County, MD, Talbot County, MD

The radar

The Dover AFB radar (KDOX), 62 km from the middle of the area, began a volume at 22:48 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
Jun 21, 7:07 PM EDTTSTM WND GST 56New Castle County Airpo, DE
Jun 21, 7:09 PM EDTTSTM WND DMG2 Sw Still Pond, MDDOWNED POWER LINES NEAR CLARK ROAD. TIME ESTIMATED FROM RADAR.
Jun 21, 7:13 PM EDTTSTM WND DMGNew Castle, DEDOWNED WIRES NEAR SECOND STREET. TIME ESTIMATED FROM RADAR.
Jun 21, 7:15 PM EDTTSTM WND DMG5 Nne Kennedyville, MDDOWNED POWER LINES NEAR BELCHESTER ROAD. TIME ESTIMATED FROM RADAR.
Jun 21, 7:15 PM EDTTSTM WND DMGGlendale, DESEVERAL REPORTS OF DOWNED TREE LIMBS AND POWER LINES IN THE AREA. TIME ESTIMATED FROM RADAR.
Jun 21, 7:20 PM EDTTSTM WND DMGMiddletown, DESOME LARGE LIMBS BLOWN DOWN IN THE MIDDLETOWN DE AREA. TIME ESTIMATED FROM RADAR.
Jun 21, 7:23 PM EDTTSTM WND DMGChestertown, MDDOWNED POWER LINES NEAR WALDO DRIVE. TIME ESTIMATED FROM RADAR.
Jun 21, 7:29 PM EDTTSTM WND DMG2 Nne Mcdonough, DEDOWNED POWER LINES NEAR PORT PENN ROAD. TIME ESTIMATED FROM RADAR.
Jun 21, 7:45 PM EDTTSTM WND DMG2 Se Delaney Corner, DEDOWNED TREE ON WIRES NEAR LONGRIDGE ROAD. TIME ESTIMATED FROM RADAR.

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.

IssuedProductOfficeLasted
Jun 21, 4:33 PM EDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 10.8 hours before the alert went out and 113 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 12:00Z on 2021-06-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 329 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 12:00Z on 2021-06-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 33 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
329 J/kg
Mixed-layer CIN
-164 J/kg
Mixed-layer LCL
801 m above ground
0-6 km bulk shear
11 kt
0-1 km storm-relative helicity
33 m²/s²
0-3 km storm-relative helicity
40 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

641 
WUUS51 KPHI 212247
SVRPHI
DEC001-003-MDC011-029-035-041-212345-
/O.NEW.KPHI.SV.W.0098.210621T2247Z-210621T2345Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
647 PM EDT Mon Jun 21 2021

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  New Castle County in northern Delaware...
  Kent County in central Delaware...
  Northern Talbot County in eastern Maryland...
  Queen Anne's County in northeastern Maryland...
  Caroline County in eastern Maryland...
  Kent County in northeastern Maryland...

* Until 745 PM EDT.

* At 647 PM EDT, severe thunderstorms were located along a line
  extending from near Octoraro to Kettering, moving east 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, Newark, Middletown, Easton, Centerville, Talbot, Pennsville,
  Smyrna, New Castle, Chestertown, Denton, Centreville, Harrington,
  Romancoke, Camden, Clayton, Greensboro, Oakland, Delaware City and
  Ridgely.

This includes Interstate 95 in Delaware between mile markers 0 and 6.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3902 7632 3900 7617 3901 7620 3916 7628
      3926 7621 3938 7606 3938 7577 3965 7579
      3971 7553 3916 7545 3884 7555 3874 7609
      3877 7632 3878 7633 3886 7626 3879 7620
      3879 7619 3897 7625 3884 7637 3885 7638
TIME...MOT...LOC 2247Z 273DEG 23KT 3964 7620 3887 7679 

HAIL...<.75IN
WIND...60MPH
 
$$

NC
1 follow-up statement
404 
WWUS51 KPHI 212328
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
728 PM EDT Mon Jun 21 2021

DEC001-003-MDC011-029-035-041-212345-
/O.CON.KPHI.SV.W.0098.000000T0000Z-210621T2345Z/
New Castle DE-Kent DE-Talbot MD-Queen Anne's MD-Caroline MD-Kent MD-
728 PM EDT Mon Jun 21 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 745 PM EDT
FOR NEW CASTLE...KENT...NORTHERN TALBOT...QUEEN ANNE'S...CENTRAL
CAROLINE AND NORTHEASTERN KENT COUNTIES...

At 728 PM EDT, severe thunderstorms were located along a line
extending from Glasgow to near Talbot, moving east at 40 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
Dover, Newark, Middletown, Centerville, Talbot, Smyrna, New Castle,
Chestertown, Denton, Centreville, Harrington, Camden, Clayton,
Greensboro, Oakland, Delaware City, Ridgely, Cheswold, Church Hill
and Millington.

This includes Interstate 95 in Delaware between mile markers 0 and 6.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 3885 7627 3882 7624 3883 7619 3895 7623
      3900 7617 3902 7619 3937 7598 3938 7577
      3965 7579 3971 7553 3962 7556 3958 7551
      3954 7554 3950 7550 3950 7554 3946 7554
      3945 7549 3915 7545 3884 7555 3881 7630
TIME...MOT...LOC 2328Z 276DEG 35KT 3960 7572 3883 7631 

HAIL...<.75IN
WIND...60MPH
 
$$

Fitzsimmons

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 21, 7:43 PM EDTSevere Thunderstorm WarningPHICaroline, Kent, Queen Anne's47 min
Jun 21, 4:35 AM EDTHeat AdvisoryPHINew Castle15 hr
Jun 21, 6:21 PM EDTSevere Thunderstorm WarningPHINew Castle54 min
Jun 21, 7:12 PM EDTSevere Thunderstorm WarningPHINew Castle48 min

Nearby

Severe Thunderstorm Warnings in Maryland, 2021Severe 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.