Alert archive / Delaware / Severe Thunderstorm Warnings in 2008

Severe Thunderstorm Warning 252, NWS Philadelphia/Mount Holly

August 15, 2008Sussex County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 15, 2008, 3:11 PM EDT for Sussex County, Delaware. It was in force for 64 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 15, 2008, 3:11 PM EDT (19:11 UTC)
Expired
Aug 15, 2008, 4:15 PM EDT
In force
64 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon

County Sussex County, DE

The radar

The Dover AFB radar (KDOX), 30 km from the middle of the area, began a volume at 19:13 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

TimeReportWhereRemark
Aug 15, 3:20 PM EDTHAIL 0.88Rehoboth Beach, DENICKEL SIZE HAIL REPORTED IN REHOBOTH BEACH.
Aug 15, 3:20 PM EDTHAIL 0.88Rehoboth Beach, DE

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, 7.2 hours before the alert went out and 92 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 12:00Z on 2008-08-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1087 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 12:00Z on 2008-08-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 44 square meters per square second.1939587897Sfc1 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
1087 J/kg
Mixed-layer CIN
-41 J/kg
Mixed-layer LCL
657 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
44 m²/s²
0-3 km storm-relative helicity
50 m²/s²
Significant tornado parameter
0.1
Supercell composite
0.9

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
WUUS51 KPHI 151911
SVRPHI
DEC005-152015-
/O.NEW.KPHI.SV.W.0252.080815T1911Z-080815T2015Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
311 PM EDT FRI AUG 15 2008

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  EAST CENTRAL SUSSEX COUNTY IN SOUTHERN DELAWARE...

* UNTIL 415 PM EDT

* AT 308 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING NICKEL SIZE HAIL...AND
  DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS LOCATED NEAR
  REHOBOTH BEACH...OR ABOUT 16 MILES EAST OF GEORGETOWN...AND MOVING
  EAST AT 8 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  REHOBOTH BEACH BY 320 PM...

THUNDERSTORMS ARE CAPABLE OF PRODUCING HEAVY RAINFALL WHICH MAY
RESULT IN LOCALIZED AREAS OF FLOODING. DO NOT DRIVE IN AREAS WHERE
WATER IS CROSSING THE ROAD.

LAT...LON 3863 7522 3881 7522 3882 7518 3879 7514
      3879 7511 3881 7509 3879 7507 3872 7507
      3866 7505 3866 7506 3861 7505
TIME...MOT...LOC 1910Z 269DEG 7KT 3873 7510

$$

SZATKOWSKI
1 follow-up statement
000 
WWUS51 KPHI 151930
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
330 PM EDT FRI AUG 15 2008

DEC005-152015-
/O.CON.KPHI.SV.W.0252.000000T0000Z-080815T2015Z/
SUSSEX DE-
330 PM EDT FRI AUG 15 2008

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 415 PM EDT
FOR EAST CENTRAL SUSSEX COUNTY...

AT 320 PM EDT...A TRAINED WEATHER SPOTTER REPORTED NICKEL SIZE HAIL 
IN REHOBOTH BEACH. THIS SEVERE STORM WAS LOCATED NEAR REHOBOTH 
BEACH...OR 16 MILES EAST OF GEORGETOWN...MOVING EAST AT 7 MPH. THIS 
STORM HAS THE POTENTIAL TO ALSO PRODUCE DAMAGING WINDS TO 60 MPH.

THE SEVERE THUNDERSTORM WILL BE NEAR...
  DEWEY BEACH BY 335 PM EDT...

IN ADDITION TO LARGE HAIL AND DAMAGING WINDS...FREQUENT CLOUD TO
GROUND LIGHTNING IS OCCURRING WITH THIS STORM. MOVE INDOORS
IMMEDIATELY LIGHTNING IS ONE OF NATURES NUMBER ONE KILLERS.
REMEMBER...IF YOU CAN HEAR THUNDER...YOU ARE CLOSE ENOUGH TO BE
STRUCK BY LIGHTNING.

LAT...LON 3863 7522 3881 7522 3882 7518 3879 7514
      3879 7511 3881 7509 3879 7507 3872 7507
      3866 7505 3866 7506 3861 7505
TIME...MOT...LOC 1928Z 287DEG 6KT 3870 7509

$$

GORSE

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 15, 3:42 PM EDTFlash Flood WarningPHISussex4 hr
Aug 15, 4:16 PM EDTSevere Thunderstorm WarningPHISussex74 min
Aug 15, 5:24 PM EDTFlash Flood WarningPHISussex2 hr

Nearby

Severe Thunderstorm Warnings in Delaware, 2008Every severe thunderstorm warning in 2008

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.