Alert archive / Delaware / Special Weather Statements in 2018

Special Weather Statement, NWS Philadelphia/Mount Holly

August 18, 2018Kent County, Delaware

NWS Philadelphia/Mount Holly issued this special weather statement at Aug 18, 2018, 9:49 PM EDT for Kent County, Delaware. It was in force for 26 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 18, 2018, 9:49 PM EDT (01:49 UTC)
Expired
Aug 18, 2018, 10:15 PM EDT
In force
26 min
Issued by
NWS Philadelphia/Mount Holly

County Kent County, DE

The radar

The Dover AFB radar (KDOX), 22 km from the middle of the area, began a volume at 01:49 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 00:00Z, 1.8 hours before the alert went out and 122 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 00:00Z on 2018-08-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1988 joules per kilogram.LCLLFCEL10008507005003002001001 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 00:00Z on 2018-08-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 41 square meters per square second.193958Sfc1 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
1988 J/kg
Mixed-layer CIN
-5 J/kg
Mixed-layer LCL
748 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
41 m²/s²
0-3 km storm-relative helicity
48 m²/s²
Significant tornado parameter
0.3
Supercell composite
2.2

Open this sounding in Storm Lab

The text

As transmitted.

654 
WWUS81 KPHI 190149
SPSPHI

Special Weather Statement
National Weather Service Mount Holly NJ
949 PM EDT SAT AUG 18 2018

DEZ002-190215-
Kent-
949 PM EDT SAT AUG 18 2018

...A STRONG THUNDERSTORM WILL AFFECT CENTRAL KENT COUNTY...

At 949 PM EDT, a strong thunderstorm was located over Rising
Sun-Lebanon, or near Dover, moving east at 15 mph.

Winds up to 40 mph are possible with this storm.

This storm will be near...
  Bowers around 1010 PM EDT.
  Big Stone Beach around 1015 PM EDT.

Other locations impacted by this storm include Highland Acres,
Felton, Rodney Village, Woodside East, Frederica, Wyoming, Little
Creek, Kent Acres, Magnolia and Riverview.

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

Frequent cloud to ground lightning is also occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

LAT...LON 3900 7562 3905 7567 3913 7557 3919 7554
      3917 7541 3907 7541 3903 7534 3897 7531
      3895 7536 3896 7536 3895 7537 3896 7539
      3893 7542
TIME...MOT...LOC 0149Z 291DEG 15KT 3908 7550 

$$

JRK

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 18, 8:52 PM EDTSpecial Weather StatementPHIOcean23 min
Aug 18, 9:07 PM EDTSpecial Marine WarningPHI83 min
Aug 18, 9:23 PM EDTSpecial Marine WarningPHI97 min
Aug 19, 1:03 AM EDTAreal Flood AdvisoryPHICape May4 hr
Aug 19, 3:31 AM EDTAreal Flood AdvisoryPHIAtlantic, Burlington, Ocean101 min
Aug 19, 4:11 AM EDTAreal Flood WarningPHIOcean4 hr
Aug 19, 10:00 AM EDTAreal Flood AdvisoryPHIChester, Delaware, Montgomery, Philadelphia110 min
Aug 19, 2:05 PM EDTAreal Flood AdvisoryPHIChester, Delaware8 hr
Aug 19, 1:11 AM EDTAreal Flood AdvisoryPHIKent, Sussex3 hr

Nearby

Special Weather Statements in Delaware, 2018Every special weather statement 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.