Alert archive / Delaware / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 28, NWS Philadelphia/Mount Holly

June 9, 2018Kent County, Sussex County, Delaware; Caroline County, Maryland

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jun 9, 2018, 2:24 PM EDT for Kent County, Sussex County, Delaware; Caroline County, Maryland. It was in force for 51 min. 1 report 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 9, 2018, 2:24 PM EDT (18:24 UTC)
Expired: Jun 9, 2018, 3:15 PM EDT
In force: 51 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Kent County, DE, Sussex County, DE, Caroline County, MD

The radar

The Dover AFB radar (KDOX), 18 km from the middle of the area, began a volume at 18:27 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
Jun 9, 2:46 PM EDT	TSTM WND DMG	2 Ne Seaford, DE	LARGE TREE DOWN ON THOMAS STREET IN SEAFORD

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 12:00Z, 6.4 hours before the alert went out and 95 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: 733 J/kg
Mixed-layer CIN: -48 J/kg
Mixed-layer LCL: 972 m above ground
0-6 km bulk shear: 17 kt
0-1 km storm-relative helicity: 60 m²/s²
0-3 km storm-relative helicity: 51 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

064 
WUUS51 KPHI 091824
SVRPHI
DEC001-005-MDC011-091915-
/O.NEW.KPHI.SV.W.0028.180609T1824Z-180609T1915Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
224 PM EDT SAT JUN 9 2018

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Northwestern Sussex County in southern Delaware...
  Southwestern Kent County in central Delaware...
  Southeastern Caroline County in eastern Maryland...

* Until 315 PM EDT.

* At 223 PM EDT, a severe thunderstorm was located over Agner, or 10
  miles north of Hurlock, moving east 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...
  Seaford, Denton, Bridgeville, Agner, Smithville, Andrewsville and
  Greenwood.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

In addition to large 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.

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

&&

LAT...LON 3871 7578 3875 7587 3887 7586 3888 7575
      3886 7550 3880 7543 3874 7540 3867 7542
      3864 7552
TIME...MOT...LOC 1823Z 283DEG 13KT 3878 7582 

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

JRK

3 follow-up statements

222 
WWUS51 KPHI 091846
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
246 PM EDT SAT JUN 9 2018

DEC001-005-MDC011-091915-
/O.CON.KPHI.SV.W.0028.000000T0000Z-180609T1915Z/
Sussex DE-Kent DE-Caroline MD-
246 PM EDT SAT JUN 9 2018

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 315 PM EDT
FOR NORTHWESTERN SUSSEX...SOUTHWESTERN KENT AND SOUTHEASTERN CAROLINE
COUNTIES...

At 245 PM EDT, a severe thunderstorm was located over Smithville, or
12 miles northeast of Hurlock, moving east at 15 mph.

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

SOURCE...Radar indicated.

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

This severe storm will be near...
  Andrewsville around 255 PM EDT.
  Seaford and Bridgeville around 315 PM EDT.

Other locations impacted by this severe thunderstorm include
Greenwood.

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.

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

&&

LAT...LON 3872 7581 3888 7574 3886 7550 3880 7543
      3874 7540 3867 7542 3864 7552 3871 7578
TIME...MOT...LOC 1845Z 285DEG 13KT 3876 7572 

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

JRK

899 
WWUS51 KPHI 091900
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
300 PM EDT SAT JUN 9 2018

DEC001-MDC011-091910-
/O.CAN.KPHI.SV.W.0028.000000T0000Z-180609T1915Z/
Kent DE-Caroline MD-
300 PM EDT SAT JUN 9 2018

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHWESTERN KENT AND
SOUTHEASTERN CAROLINE 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 3869 7570 3882 7566 3878 7542 3874 7540
      3867 7542 3864 7552
TIME...MOT...LOC 1900Z 287DEG 16KT 3874 7563 

$$

DEC005-091915-
/O.CON.KPHI.SV.W.0028.000000T0000Z-180609T1915Z/
Sussex DE-
300 PM EDT SAT JUN 9 2018

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 315 PM EDT
FOR WEST CENTRAL SUSSEX COUNTY...

At 300 PM EDT, a severe thunderstorm was located over Bridgeville, or
13 miles west of Georgetown, moving east at 20 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

This severe storm will be near...
  Seaford around 310 PM EDT.

Other locations impacted by this severe thunderstorm include
Greenwood.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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.

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

&&

LAT...LON 3869 7570 3882 7566 3878 7542 3874 7540
      3867 7542 3864 7552
TIME...MOT...LOC 1900Z 287DEG 16KT 3874 7563 

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

JRK

227 
WWUS51 KPHI 091913
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
313 PM EDT SAT JUN 9 2018

DEC005-091922-
/O.EXP.KPHI.SV.W.0028.000000T0000Z-180609T1915Z/
Sussex DE-
313 PM EDT SAT JUN 9 2018

...THE SEVERE THUNDERSTORM WARNING FOR WEST CENTRAL SUSSEX COUNTY
WILL EXPIRE AT 315 PM EDT...
        
The storm which prompted the warning has moved out of the area.
Therefore, the warning will be allowed to expire.  However gusty
winds and heavy rain are still possible with this thunderstorm.

Remember, a Severe Thunderstorm Warning still remains in effect 
farther south across southern Sussex County until 330 PM.

LAT...LON 3869 7570 3882 7566 3878 7542 3874 7540
      3867 7542 3864 7552
TIME...MOT...LOC 1912Z 283DEG 13KT 3873 7558 

$$

JRK

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 9, 12:51 PM EDT	Special Weather Statement	PHI	Sussex	24 min
Jun 9, 1:04 PM EDT	Special Weather Statement	PHI	Kent	56 min
Jun 9, 1:21 PM EDT	Severe Thunderstorm Warning	PHI	Kent	39 min
Jun 9, 1:25 PM EDT	Flash Flood Warning	PHI	Sussex	4 hr
Jun 9, 1:35 PM EDT	Areal Flood Advisory	PHI	Kent	71 min
Jun 9, 1:35 PM EDT	Special Weather Statement	PHI	Sussex	25 min
Jun 9, 2:00 PM EDT	Special Weather Statement	PHI	Sussex	30 min
Jun 9, 2:42 PM EDT	Areal Flood Advisory	PHI	Kent, Sussex	58 min
Jun 9, 2:48 PM EDT	Severe Thunderstorm Warning	PHI	Sussex	42 min
Jun 9, 2:53 PM EDT	Flash Flood Warning	PHI	Sussex	4 hr
Jun 9, 3:06 PM EDT	Special Weather Statement	PHI	New Castle	24 min
Jun 9, 3:26 PM EDT	Special Weather Statement	PHI	Sussex	34 min
Jun 9, 3:45 PM EDT	Special Weather Statement	PHI	Kent	45 min
Jun 9, 3:47 PM EDT	Areal Flood Advisory	PHI	Kent, New Castle	3 hr
Jun 9, 3:53 PM EDT	Severe Thunderstorm Warning	PHI	Kent, New Castle	37 min
Jun 9, 4:06 PM EDT	Special Weather Statement	PHI	Sussex	39 min
Jun 9, 4:15 PM EDT	Flash Flood Warning	PHI	Sussex	3 hr
Jun 9, 4:20 PM EDT	Flash Flood Warning	PHI	Kent	3 hr
Jun 9, 4:24 PM EDT	Special Weather Statement	PHI	Kent	51 min
Jun 9, 5:31 PM EDT	Special Weather Statement	PHI	Sussex	44 min
Jun 9, 5:44 PM EDT	Areal Flood Warning	PHI	Sussex	4 hr
Jun 9, 6:44 PM EDT	Areal Flood Warning	PHI	Sussex	3 hr

Nearby

Severe Thunderstorm Warnings in Delaware, 2018 Severe Thunderstorm Warnings in Maryland, 2018 Every severe thunderstorm warning in 2018

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.