Alert archive / Delaware / Severe Thunderstorm Warnings in 2007

Severe Thunderstorm Warning 154, NWS Philadelphia/Mount Holly

July 28, 2007Sussex County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 28, 2007, 3:23 PM EDT for Sussex County, Delaware. It was in force for 37 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 28, 2007, 3:23 PM EDT (19:23 UTC)
Expired
Jul 28, 2007, 4:00 PM EDT
In force
37 min
Issued by
NWS Philadelphia/Mount Holly
Area
Counties, with a storm outline in the text

County Sussex County, DE

The nearest sounding before it

Wallops Is Stn, VA (KWAL), launched 12:00Z, 7.4 hours before the alert went out and 77 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 2007-07-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1581 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 2007-07-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 14 square meters per square second.1939Sfc1 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
1581 J/kg
Mixed-layer CIN
-62 J/kg
Mixed-layer LCL
823 m above ground
0-6 km bulk shear
15 kt
0-1 km storm-relative helicity
14 m²/s²
0-3 km storm-relative helicity
36 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

000 
WUUS51 KPHI 281924
SVRPHI
DEC005-282000-
/O.NEW.KPHI.SV.W.0154.070728T1923Z-070728T2000Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
323 PM EDT SAT JUL 28 2007

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  EASTERN SUSSEX COUNTY IN SOUTHERN DELAWARE...

* UNTIL 400 PM EDT

* AT 320 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING PENNY SIZE HAIL...AND
  DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS LOCATED NEAR
  MILLSBORO...OR ABOUT 40 MILES SOUTH OF DOVER. THIS STORM WAS NEARLY
  STATIONARY.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  7 MILES SOUTHEAST OF GEORGETOWN BY 400 PM EDT...

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 3851 7535 3855 7513 3880 7515 3873 7549

$$

AMC
2 follow-up statements
000 
WWUS51 KPHI 281948
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
346 PM EDT SAT JUL 28 2007

DEC005-282000-
/O.CON.KPHI.SV.W.0154.000000T0000Z-070728T2000Z/
SUSSEX DE-
346 PM EDT SAT JUL 28 2007

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 400 PM EDT
FOR EAST CENTRAL SUSSEX COUNTY...

AT 343 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING PENNY SIZE
HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS
LOCATED NEAR MILLSBORO...OR ABOUT 41 MILES SOUTH OF DOVER. THIS STORM
WAS NEARLY STATIONARY.

THE SEVERE THUNDERSTORM WILL BE NEAR...
  RURAL EASTERN SUSSEX COUNTY AT 400 PM EDT

IN ADDITION TO LARGE HAIL AND DAMAGING WINDS...CONTINUOUS 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.

ALSO...RADAR IS ESTIMATING THAT 2 TO 2.5 INCHES OF RAIN MAY HAVE 
FALLEN FROM THIS STORM WITHIN THE PAST HOUR OR SO. WATCH OUT FOR 
PONDING OF WATER ON ROADWAYS AND FOR OVERFLOWING DITCHES AND SMALL 
STREAMS.

LAT...LON 3847 7533 3847 7512 3874 7513 3874 7536

$$

AMC
000 
WWUS51 KPHI 282005
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
401 PM EDT SAT JUL 28 2007

DEC005-282011-
/O.EXP.KPHI.SV.W.0154.000000T0000Z-070728T2000Z/
SUSSEX DE-
401 PM EDT SAT JUL 28 2007

...THE SEVERE THUNDERSTORM WARNING FOR EAST CENTRAL SUSSEX COUNTY
EXPIRED AT 400 PM EDT...

HOWEVER...STRONG THUNDERSTORMS CONTINUE TO AFFECT THE SAME SOUTHEAST 
PART OF SUSSEX COUNTY. THESE STORMS ARE PRODUCING VERY HEAVY RAIN 
AND DANGEROUS CLOUD-TO-GROUND LIGHTNING. WATCH OUT FOR LOCALIZED 
FLOODING.  

LAT...LON 3847 7533 3847 7512 3874 7513 3874 7536

$$

AMC

Nearby

Severe Thunderstorm Warnings in Delaware, 2007Every severe thunderstorm warning in 2007

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.