Alert archive / Delaware / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 104, NWS Philadelphia/Mount Holly

July 14, 2017Sussex County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 14, 2017, 7:15 PM EDT for Sussex County, Delaware. It was in force for 60 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 14, 2017, 7:15 PM EDT (23:15 UTC)
Expired: Jul 14, 2017, 8:15 PM EDT
In force: 60 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

County Sussex County, DE

The radar

The Dover AFB radar (KDOX), 27 km from the middle of the area, began a volume at 23:16 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Jul 14, 1:40 PM EDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Wallops Is Stn, VA (KWAL), launched 12:00Z, 11.3 hours before the alert went out and 81 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: 908 J/kg
Mixed-layer CIN: -100 J/kg
Mixed-layer LCL: 959 m above ground
0-6 km bulk shear: 23 kt
0-1 km storm-relative helicity: 56 m²/s²
0-3 km storm-relative helicity: 96 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.5

Open this sounding in Storm Lab

The text

As transmitted.

815 
WUUS51 KPHI 142315
SVRPHI
DEC005-150015-
/O.NEW.KPHI.SV.W.0104.170714T2315Z-170715T0015Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
715 PM EDT FRI JUL 14 2017

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Eastern Sussex County in southern Delaware...

* Until 815 PM EDT

* At 714 PM EDT, severe thunderstorms were located along a line
  extending from near Milton to near Millsboro to near Parsonsburg,
  moving east at 25 mph.

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

  SOURCE...Radar indicated. 

  IMPACT...Minor damage to vehicles is possible. Expect damage to 
           trees and power lines. 

* Severe thunderstorms will be near,
  Lewes around 720 PM EDT. 
  Dagsboro around 725 PM EDT. 
  Henlopen Acres and Cape Henlopen State Park around 735 PM EDT. 
  Selbyville and Millville around 740 PM EDT. 

Other locations impacted by these severe thunderstorms include Long
Neck, Dewey Beach, Ocean View, South Bethany and Frankford.

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.

&&

LAT...LON 3845 7548 3861 7540 3887 7530 3888 7522
      3881 7514 3881 7506 3846 7504 3845 7505
TIME...MOT...LOC 2314Z 272DEG 22KT 3881 7525 3861 7532 3842 7542 

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

Robertson

3 follow-up statements

094 
WWUS51 KPHI 142331
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
731 PM EDT FRI JUL 14 2017

DEC005-150015-
/O.CON.KPHI.SV.W.0104.000000T0000Z-170715T0015Z/
Sussex DE-
731 PM EDT FRI JUL 14 2017

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 815 PM EDT
FOR SOUTHEASTERN SUSSEX COUNTY...

At 731 PM EDT, severe thunderstorms were located along a line
extending from Lewes to near Dagsboro to near Gumboro, moving east at
25 mph.

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

SOURCE...Radar indicated. 

IMPACT...Minor damage to vehicles is possible. Expect damage to 
         trees and power lines. 

These severe storms will be near...
  Lewes around 735 PM EDT. 
  Millville, Henlopen Acres and Cape Henlopen State Park around 740 
  PM EDT. 

Other locations impacted by these severe thunderstorms include Long
Neck, Dewey Beach, Ocean View, South Bethany and Frankford.

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.

&&

LAT...LON 3845 7543 3864 7534 3881 7512 3880 7506
      3846 7504 3845 7505
TIME...MOT...LOC 2331Z 274DEG 21KT 3876 7515 3856 7520 3840 7532 

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

Robertson

258 
WWUS51 KPHI 142352
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
752 PM EDT FRI JUL 14 2017

DEC005-150015-
/O.CON.KPHI.SV.W.0104.000000T0000Z-170715T0015Z/
Sussex DE-
752 PM EDT FRI JUL 14 2017

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 815 PM EDT
FOR SOUTHEASTERN SUSSEX COUNTY...

At 752 PM EDT, severe thunderstorms were located along a line
extending from near Henlopen Acres to near Millville to Ocean City,
moving east at 20 mph.

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

SOURCE...Radar indicated. 

IMPACT...Minor damage to vehicles is possible. Expect damage to 
         trees and power lines. 

Locations impacted include...
Millville, Long Neck, Ocean View, South Bethany and Dewey Beach. 

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.

&&

LAT...LON 3871 7515 3871 7506 3869 7505 3849 7504
      3846 7504 3845 7505 3845 7516
TIME...MOT...LOC 2352Z 276DEG 16KT 3866 7505 3853 7506 3838 7507 

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

Robertson

517 
WWUS51 KPHI 150008
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
808 PM EDT FRI JUL 14 2017

DEC005-150016-
/O.EXP.KPHI.SV.W.0104.000000T0000Z-170715T0015Z/
Sussex DE-
808 PM EDT FRI JUL 14 2017

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN SUSSEX COUNTY
WILL EXPIRE AT 815 PM EDT...
    
The storms which prompted the warning have weakened below severe
limits, and have exited the warned area. Therefore the warning will
be allowed to expire.  However gusty winds and heavy rain are still
possible with these thunderstorms.

A severe thunderstorm watch remains in effect until 900 PM EDT for
southern Delaware.

LAT...LON 3871 7515 3871 7506 3869 7505 3849 7504
      3846 7504 3845 7505 3845 7516
TIME...MOT...LOC 0006Z 272DEG 22KT 3866 7496 3853 7497 3838 7498 

$$

Robertson

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 13, 8:09 PM EDT	Special Weather Statement	PHI	Kent	36 min
Jul 13, 8:29 PM EDT	Special Weather Statement	PHI	Kent	31 min
Jul 13, 10:03 PM EDT	Special Weather Statement	PHI	Sussex	27 min
Jul 13, 10:15 PM EDT	Areal Flood Advisory	PHI	Kent, Sussex	4 hr
Jul 13, 10:39 PM EDT	Severe Thunderstorm Warning	PHI	Sussex	51 min
Jul 14, 9:02 AM EDT	Special Weather Statement	PHI	New Castle	28 min
Jul 14, 11:40 AM EDT	Flash Flood Watch	PHI	Kent, New Castle	11 hr
Jul 14, 12:06 PM EDT	Heat Advisory	PHI	Kent, Sussex	7 hr
Jul 14, 2:14 PM EDT	Areal Flood Advisory	PHI	New Castle	3 hr
Jul 14, 2:31 PM EDT	Severe Thunderstorm Warning	PHI	New Castle	59 min
Jul 14, 2:53 PM EDT	Flash Flood Warning	PHI	New Castle	3 hr
Jul 14, 3:18 PM EDT	Severe Thunderstorm Warning	PHI	New Castle	12 min
Jul 14, 3:23 PM EDT	Severe Thunderstorm Warning	PHI	New Castle	67 min
Jul 14, 3:25 PM EDT	Areal Flood Advisory	PHI	New Castle	4 hr
Jul 14, 3:34 PM EDT	Flash Flood Warning	PHI	New Castle	3 hr
Jul 14, 3:54 PM EDT	Severe Thunderstorm Warning	PHI	Kent, New Castle	66 min
Jul 14, 5:14 PM EDT	Areal Flood Advisory	PHI	Kent	3 hr
Jul 14, 5:24 PM EDT	Special Weather Statement	PHI	Sussex	36 min
Jul 14, 5:30 PM EDT	River Flood Warning	PHI	New Castle	7 hr
Jul 14, 5:40 PM EDT	Severe Thunderstorm Warning	PHI	Kent	65 min
Jul 14, 5:51 PM EDT	Special Weather Statement	PHI	Sussex	39 min
Jul 14, 6:10 PM EDT	Flash Flood Warning	PHI	Kent	3 hr
Jul 14, 6:20 PM EDT	Severe Thunderstorm Warning	PHI	Kent, Sussex	40 min
Jul 14, 6:32 PM EDT	Areal Flood Advisory	PHI	Sussex	4 hr
Jul 14, 6:48 PM EDT	Special Weather Statement	PHI	Sussex	42 min

Nearby

Severe Thunderstorm Warnings in Delaware, 2017 Every 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.