Alert archive / Maryland / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 68, NWS Philadelphia/Mount Holly

June 21, 2017Kent County, Delaware; Caroline County, Queen Anne's County, Maryland

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jun 21, 2017, 7:42 PM EDT for Kent County, Delaware; Caroline County, Queen Anne's County, Maryland. It was in force for 36 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
Jun 21, 2017, 7:42 PM EDT (23:42 UTC)
Expired
Jun 21, 2017, 8:18 PM EDT
In force
36 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, Queen Anne's County, MD

The radar

The Dover AFB radar (KDOX), 36 km from the middle of the area, began a volume at 23:43 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, 11.7 hours before the alert went out and 132 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 2017-06-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 2017-06-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 13 square meters per square second.19395878Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1471 m above ground
0-6 km bulk shear
50 kt
0-1 km storm-relative helicity
13 m²/s²
0-3 km storm-relative helicity
-98 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

379 
WUUS51 KPHI 212342
SVRPHI
DEC001-MDC011-035-220030-
/O.NEW.KPHI.SV.W.0068.170621T2342Z-170622T0030Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
742 PM EDT WED JUN 21 2017

The National Weather Service in Mount Holly NJ has issued a

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

* Until 830 PM EDT

* At 742 PM EDT, severe thunderstorms were located along a line
  extending from Church Hill to Dover Speedway to near Woodland
  Beach, moving southeast at 35 mph.

  HAZARD...60 mph wind gusts. 

  SOURCE...Radar indicated. 

  IMPACT...Expect damage to trees and power lines. 

* Locations impacted include...
  Dover, Camden, Greensboro, Oakland, Cheswold, Church Hill,
  Sudlersville, Bowers, Goldsboro, Woodside, Viola, Hartly, Rising
  Sun-Lebanon, Hazlettville, Dover Base Housing, Dover Speedway,
  Sandtown, Rising Sun, Carville and Hope.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

In addition to 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 3916 7601 3922 7586 3923 7558 3929 7545
      3922 7537 3905 7537 3895 7531 3896 7539
      3894 7567 3897 7585 3905 7602
TIME...MOT...LOC 2342Z 295DEG 30KT 3915 7595 3918 7551 3929 7540 

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

JRK
1 follow-up statement
861 
WWUS51 KPHI 220018
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
818 PM EDT WED JUN 21 2017

DEC001-MDC011-035-220028-
/O.CAN.KPHI.SV.W.0068.000000T0000Z-170622T0030Z/
Kent DE-Queen Anne's MD-Caroline MD-
818 PM EDT WED JUN 21 2017

...THE SEVERE THUNDERSTORM WARNING FOR KENT...NORTHEASTERN QUEEN
ANNE'S AND NORTHEASTERN CAROLINE COUNTIES IS CANCELLED...
    
The storms which prompted the warning have weakened below severe
limits, and have exited the warned area. Therefore the warning has
been cancelled.

LAT...LON 3916 7601 3922 7586 3923 7558 3929 7545
      3922 7537 3905 7537 3895 7531 3896 7539
      3894 7567 3897 7585 3905 7602
TIME...MOT...LOC 0016Z 295DEG 30KT 3903 7561 3906 7518 3917 7506 

$$

JRK

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 21, 6:27 PM EDTSpecial Weather StatementPHINew Castle33 min
Jun 21, 6:57 PM EDTSevere Thunderstorm WarningPHIKent, New Castle48 min
Jun 21, 2:51 PM EDTSpecial Weather StatementPHITalbot39 min

Nearby

Severe Thunderstorm Warnings in Maryland, 2017Severe Thunderstorm Warnings in Delaware, 2017Every severe thunderstorm warning in 2017

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.