Alert archive / Delaware / Special Weather Statements in 2017

Special Weather Statement, NWS Philadelphia/Mount Holly

August 7, 2017Sussex County, Delaware

NWS Philadelphia/Mount Holly issued this special weather statement at Aug 7, 2017, 1:47 PM EDT for Sussex County, Delaware. It was in force for 43 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: Aug 7, 2017, 1:47 PM EDT (17:47 UTC)
Expired: Aug 7, 2017, 2:30 PM EDT
In force: 43 min
Issued by: NWS Philadelphia/Mount Holly

County Sussex County, DE

The radar

The Dover AFB radar (KDOX), 31 km from the middle of the area, began a volume at 17:46 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, 5.8 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: 57 J/kg
Mixed-layer CIN: -91 J/kg
Mixed-layer LCL: 996 m above ground
0-6 km bulk shear: 45 kt
0-1 km storm-relative helicity: 176 m²/s²
0-3 km storm-relative helicity: 193 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.3

Open this sounding in Storm Lab

The text

As transmitted.

283 
WWUS81 KPHI 071747
SPSPHI

Special Weather Statement
National Weather Service Mount Holly NJ
147 PM EDT MON AUG 7 2017

DEZ003-004-071830-
Inland Sussex-Delaware Beaches-
147 PM EDT MON AUG 7 2017

...A STRONG THUNDERSTORM WILL AFFECT SUSSEX COUNTY...

At 147 PM EDT, a strong thunderstorm was located over Delmar, or near
Salisbury, moving northeast at 40 mph.

Winds up to 50 mph are possible with this storm.

Locations impacted include...
Georgetown, Millsboro, Laurel, Lewes, Milton, Selbyville, Delmar,
Dagsboro, Millville, Henlopen Acres, Gumboro, Cape Henlopen State
Park, Sycamore, Long Neck, Ocean View, Frankford, South Bethany and
Dewey Beach.

Torrential rainfall is also occurring with this storm, and may cause
localized flooding. Do not drive your vehicle through flooded
roadways.

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

LAT...LON 3846 7566 3893 7533 3880 7518 3880 7509
      3867 7507 3869 7508 3869 7514 3864 7513
      3862 7508 3866 7507 3861 7506 3859 7521
      3857 7518 3858 7507 3860 7509 3860 7506
      3845 7505
TIME...MOT...LOC 1747Z 213DEG 33KT 3844 7555 

$$

CMS

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 7, 9:59 AM EDT	Areal Flood Advisory	PHI	Cumberland, Salem	3 hr
Aug 7, 12:36 PM EDT	Areal Flood Advisory	PHI	Atlantic, Cape May, Cumberland, Salem	4 hr
Aug 7, 1:23 PM EDT	Flash Flood Warning	PHI	Cumberland	4 hr
Aug 7, 2:04 PM EDT	Special Marine Warning	PHI		56 min
Aug 7, 2:53 PM EDT	Special Marine Warning	PHI		67 min
Aug 7, 3:25 PM EDT	Areal Flood Advisory	PHI	Atlantic, Burlington, Camden, Cumberland, Gloucester, Ocean	4 hr
Aug 7, 3:57 PM EDT	Special Marine Warning	PHI		63 min
Aug 7, 4:24 PM EDT	Areal Flood Warning	PHI	Atlantic, Burlington, Cape May, Cumberland, Gloucester, Ocean	4 hr
Aug 7, 4:59 PM EDT	Special Marine Warning	PHI		91 min
Aug 7, 8:54 AM EDT	Areal Flood Advisory	PHI	Cecil, Kent, Queen Anne's	3 hr
Aug 7, 10:44 AM EDT	Flash Flood Warning	PHI	Caroline, Queen Anne's, Talbot	4 hr
Aug 7, 11:41 AM EDT	Areal Flood Advisory	PHI	Caroline, Talbot	3 hr
Aug 7, 1:35 PM EDT	Flash Flood Warning	PHI	Caroline, Queen Anne's, Talbot	4 hr
Aug 7, 2:40 PM EDT	Areal Flood Warning	PHI	Caroline, Queen Anne's, Talbot	6 hr
Aug 7, 4:32 PM EDT	Special Weather Statement	PHI	Talbot	58 min
Aug 7, 5:25 PM EDT	Areal Flood Warning	PHI	Caroline, Queen Anne's, Talbot	4 hr
Aug 7, 1:58 PM EDT	Severe Thunderstorm Warning	PHI	Sussex	47 min
Aug 7, 2:06 PM EDT	Flash Flood Warning	PHI	Kent, Sussex	4 hr
Aug 7, 2:08 PM EDT	Tornado Warning	PHI	Sussex	37 min
Aug 7, 2:22 PM EDT	Areal Flood Advisory	PHI	Sussex	4 hr
Aug 7, 2:41 PM EDT	Severe Thunderstorm Warning	PHI	Sussex	34 min
Aug 7, 4:57 PM EDT	Areal Flood Warning	PHI	Sussex	4 hr

Nearby

Special Weather Statements in Delaware, 2017 Every special weather statement 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.