Alert archive / Delaware / Severe Thunderstorm Warnings in 2007

Severe Thunderstorm Warning 187, NWS Philadelphia/Mount Holly

August 16, 2007Sussex County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 16, 2007, 10:16 PM EDT for Sussex County, Delaware. It was in force for 44 min. 1 report 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 16, 2007, 10:16 PM EDT (02:16 UTC)
Expired: Aug 16, 2007, 11:00 PM EDT
In force: 44 min
Issued by: NWS Philadelphia/Mount Holly
Area: Counties, with a storm outline in the text

County Sussex County, DE

The radar

The Dover AFB radar (KDOX), 34 km from the middle of the area, began a volume at 02:19 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 16, 10:30 PM EDT	TSTM WND DMG	Ocean View, DE	TREES DOWN.

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 00:00Z, 2.3 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-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: 4766 J/kg
Mixed-layer CIN: -30 J/kg
Mixed-layer LCL: 852 m above ground
0-6 km bulk shear: 30 kt
0-1 km storm-relative helicity: 175 m²/s²
0-3 km storm-relative helicity: 289 m²/s²
Significant tornado parameter: 4.7
Supercell composite: 26.2

Open this sounding in Storm Lab

The text

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

000 
WUUS51 KPHI 170217
SVRPHI
DEC005-170300-
/O.NEW.KPHI.SV.W.0187.070817T0216Z-070817T0300Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1016 PM EDT THU AUG 16 2007

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

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

* UNTIL 1100 PM EDT

* AT 1007 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 JUST
  SOUTHEAST OF MILLSBORO...OR ABOUT 43 MILES SOUTH OF DOVER...AND
  MOVING EAST AT 25 TO 30 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  7 MILES NORTH OF FENWICK ISLAND BY 1030 PM EDT...

LAT...LON 3848 7537 3866 7532 3866 7512 3865 7510
      3865 7511 3864 7510 3866 7508 3866 7507
      3845 7505
TIME...MOT...LOC 0216Z 269DEG 31KT 3856 7519

$$

JRP

1 follow-up statement

000 
WWUS51 KPHI 170237
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1036 PM EDT THU AUG 16 2007

DEC005-170300-
/O.CON.KPHI.SV.W.0187.000000T0000Z-070817T0300Z/
SUSSEX DE-
1036 PM EDT THU AUG 16 2007

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1100 PM EDT
FOR SOUTHEASTERN SUSSEX COUNTY...

AT 1035 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 BETHANY BEACH...OR 5 MILES EAST OF MILLSBORO...OR ABOUT 
48 MILES SOUTHEAST OF DOVER...MOVING EAST AT 25 MPH.

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 3848 7537 3866 7532 3866 7512 3865 7510
      3865 7511 3864 7510 3866 7508 3866 7507
      3845 7505
TIME...MOT...LOC 0236Z 269DEG 31KT 3856 7497

$$

JRP

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 16, 10:20 PM EDT	Severe Thunderstorm Warning	PHI	Sussex	55 min
Aug 16, 10:54 PM EDT	Severe Thunderstorm Warning	PHI	Sussex	36 min
Aug 16, 11:31 PM EDT	Severe Thunderstorm Warning	PHI	Sussex	25 min
Aug 17, 12:26 AM EDT	Severe Thunderstorm Warning	PHI	Sussex	22 min
Aug 17, 2:36 PM EDT	Severe Thunderstorm Warning	PHI	New Castle	54 min

Nearby

Severe Thunderstorm Warnings in Delaware, 2007 Every 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.