Alert archive / Delaware / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 150, NWS Philadelphia/Mount Holly

August 3, 2017Sussex County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 3, 2017, 2:15 PM EDT for Sussex County, Delaware. It was in force for 45 min. 2 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: Aug 3, 2017, 2:15 PM EDT (18:15 UTC)
Expired: Aug 3, 2017, 3:00 PM EDT
In force: 45 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), 21 km from the middle of the area, began a volume at 18:15 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
Aug 3, 2:36 PM EDT	TSTM WND GST 45	Sussex County Airport, DE
Aug 3, 2:37 PM EDT	TSTM WND DMG	Georgetown, DE	WIRES DOWN ON CEDAR LANE. TIME ESTIMATED FROM RADAR.

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, 6.3 hours before the alert went out and 83 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: 204 J/kg
Mixed-layer CIN: -106 J/kg
Mixed-layer LCL: 1338 m above ground
0-6 km bulk shear: 15 kt
0-1 km storm-relative helicity: 39 m²/s²
0-3 km storm-relative helicity: 23 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

588 
WUUS51 KPHI 031815
SVRPHI
DEC005-031900-
/O.NEW.KPHI.SV.W.0150.170803T1815Z-170803T1900Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
215 PM EDT THU AUG 3 2017

The National Weather Service in Mount Holly NJ has issued a

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

* Until 300 PM EDT

* At 215 PM EDT, a severe thunderstorm was located near Georgetown,
  and is nearly stationary.

  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...
  Georgetown, Millsboro, Lewes, Milton, Dagsboro and Long Neck. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 3867 7552 3892 7529 3866 7505 3863 7504
      3849 7533
TIME...MOT...LOC 1815Z 222DEG 4KT 3864 7535 

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

CMS

2 follow-up statements

320 
WWUS51 KPHI 031836
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
236 PM EDT THU AUG 3 2017

DEC005-031900-
/O.CON.KPHI.SV.W.0150.000000T0000Z-170803T1900Z/
Sussex DE-
236 PM EDT THU AUG 3 2017

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 300 PM EDT
FOR CENTRAL SUSSEX COUNTY...

At 235 PM EDT, a severe thunderstorm was located near and just 
southeast of Georgetown, and is nearly stationary.

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...
Georgetown, Millsboro, Lewes, Milton, Dagsboro and Long Neck. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 3868 7551 3890 7531 3892 7529 3866 7505
      3863 7504 3851 7529
TIME...MOT...LOC 1835Z 222DEG 4KT 3866 7533 

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

CMS

089 
WWUS51 KPHI 031856
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
256 PM EDT THU AUG 3 2017

DEC005-031905-
/O.EXP.KPHI.SV.W.0150.000000T0000Z-170803T1900Z/
Sussex DE-
256 PM EDT THU AUG 3 2017

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL SUSSEX COUNTY WILL
EXPIRE AT 300 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
and heavy rain are still possible with this thunderstorm.

LAT...LON 3868 7551 3890 7531 3892 7529 3866 7505
      3863 7504 3851 7529
TIME...MOT...LOC 1855Z 222DEG 4KT 3868 7531 

$$

CMS

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 3, 1:54 PM EDT	Special Weather Statement	PHI	Sussex	21 min
Aug 3, 2:12 PM EDT	Special Weather Statement	PHI	Sussex	33 min
Aug 3, 2:26 PM EDT	Special Weather Statement	PHI	Sussex	49 min
Aug 3, 2:59 PM EDT	Special Weather Statement	PHI	Kent, Sussex	46 min
Aug 3, 3:46 PM EDT	Areal Flood Advisory	PHI	Kent, Sussex	4 hr
Aug 3, 4:17 PM EDT	Flash Flood Warning	PHI	Kent, Sussex	4 hr
Aug 3, 5:01 PM EDT	Special Weather Statement	PHI	Kent	29 min
Aug 3, 5:20 PM EDT	Special Weather Statement	PHI	Sussex	25 min
Aug 3, 5:33 PM EDT	Areal Flood Advisory	PHI	Kent	4 hr
Aug 3, 5:49 PM EDT	Areal Flood Advisory	PHI	Sussex	4 hr
Aug 3, 6:12 PM EDT	Areal Flood Advisory	PHI	Sussex	3 hr
Aug 3, 6:31 PM EDT	Special Weather Statement	PHI	Sussex	29 min
Aug 3, 7:02 PM EDT	Flash Flood Warning	PHI	Sussex	3 hr

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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.