Alert archive / Delaware / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 178, NWS Philadelphia/Mount Holly

August 9, 2012Sussex County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 9, 2012, 1:55 PM EDT for Sussex County, Delaware. It was in force for 65 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 9, 2012, 1:55 PM EDT (17:55 UTC)
Expired: Aug 9, 2012, 3:00 PM EDT
In force: 65 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon

County Sussex County, DE

The radar

The Dover AFB radar (KDOX), 32 km from the middle of the area, began a volume at 17:56 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 9, 1:55 PM EDT	TSTM WND DMG	Lewes, 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 12:00Z, 5.9 hours before the alert went out and 87 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: 2382 J/kg
Mixed-layer CIN: -4 J/kg
Mixed-layer LCL: 702 m above ground
0-6 km bulk shear: 11 kt
0-1 km storm-relative helicity: 5 m²/s²
0-3 km storm-relative helicity: -27 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.

204 
WUUS51 KPHI 091755
SVRPHI
DEC005-091900-
/O.NEW.KPHI.SV.W.0178.120809T1755Z-120809T1900Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
155 PM EDT THU AUG 9 2012

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

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

* UNTIL 300 PM EDT

* AT 152 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS IN 
  EXCESS OF 60 MPH. DOVER DOPPLER RADAR WAS SHOWING WINDS OF 
  AROUND 65 MPH. THIS STORM WAS LOCATED 6 MILES SOUTHWEST OF
  LEWES...OR   9 MILES EAST OF GEORGETOWN...AND MOVING EAST AT 10
  MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  LEWES AROUND 220 PM EDT...
  REHOBOTH BEACH AND CAPE HENLOPEN STATE PARK AROUND 235 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...PREPARE
IMMEDIATELY FOR DAMAGING WINDS...LARGE HAIL...AND DEADLY CLOUD TO
GROUND LIGHTNING. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...
PREFERABLY INSIDE A STRONG BUILDING BUT AWAY FROM WINDOWS.

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

IN ADDITION TO LARGE HAIL AND DAMAGING WINDS...HEAVY RAIN WILL OCCUR
WITH THESE STORMS AND CAUSE LOW-LYING AND POOR DRAINAGE FLOODING.

PLEASE REPORT HAIL OR STRONG WINDS TO THE NATIONAL WEATHER SERVICE BY
CALLING TOLL FREE...1-877-633-6772...WHEN YOU CAN DO SO SAFELY.

&&

LAT...LON 3865 7535 3882 7519 3879 7515 3879 7511
      3881 7509 3878 7507 3867 7506 3866 7505
      3866 7506 3860 7504 3859 7505 3851 7504
      3851 7505
TIME...MOT...LOC 1755Z 268DEG 10KT 3873 7523

$$

TFG

2 follow-up statements

412 
WWUS51 KPHI 091825
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
225 PM EDT THU AUG 9 2012

DEC005-091900-
/O.CON.KPHI.SV.W.0178.000000T0000Z-120809T1900Z/
SUSSEX DE-
225 PM EDT THU AUG 9 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 300 PM EDT
FOR EAST CENTRAL SUSSEX COUNTY...

AT 224 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING
WINDS IN EXCESS OF 60 MPH.  THESE STORMS WERE LOCATED ALONG A LINE
EXTENDING FROM LEWES TO 8 MILES NORTHWEST OF LONG NECK...OR ALONG A
LINE EXTENDING FROM 15 MILES EAST OF GEORGETOWN TO 6 MILES EAST OF
GEORGETOWN...MOVING SOUTHEAST AT 10 MPH.

SEVERE THUNDERSTORMS WILL BE NEAR...
  CAPE HENLOPEN STATE PARK BY 230 PM EDT...
  REHOBOTH BEACH BY 250 PM EDT...
  LONG NECK...DEWEY BEACH...6 MILES NORTHWEST OF MILLVILLE AND 8
  MILES NORTHWEST OF OCEAN VIEW BY 300 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...PREPARE
IMMEDIATELY FOR DAMAGING WINDS...DESTRUCTIVE HAIL...AND DEADLY CLOUD
TO GROUND LIGHTNING. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...
PREFERABLY INSIDE A STRONG BUILDING BUT AWAY FROM WINDOWS.

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

PLEASE REPORT HAIL OR STRONG WINDS TO THE NATIONAL WEATHER SERVICE BY
CALLING TOLL FREE...1-877-633-6772...WHEN YOU CAN DO SO SAFELY.

&&

LAT...LON 3866 7534 3878 7515 3879 7515 3879 7511
      3881 7509 3878 7507 3867 7506 3866 7505
      3866 7506 3860 7504 3859 7505 3851 7504
      3851 7505
TIME...MOT...LOC 1825Z 295DEG 9KT 3876 7513 3867 7528

$$

TFG

225 
WWUS51 KPHI 091847
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
247 PM EDT THU AUG 9 2012

DEC005-091900-
/O.CON.KPHI.SV.W.0178.000000T0000Z-120809T1900Z/
SUSSEX DE-
247 PM EDT THU AUG 9 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 300 PM EDT
FOR EAST CENTRAL SUSSEX COUNTY...

AT 244 PM EDT...A LINE OF SEVERE THUNDERSTORMS WAS REPORTED CAPABLE
OF PRODUCING DAMAGING WINDS TO 60 MPH.  THESE STORMS WERE
LOCATED ALONG A LINE EXTENDING FROM LONG NECK TO 10 MILES WEST OF
LONG NECK...OR ALONG A LINE EXTENDING FROM 11 MILES EAST OF
GEORGETOWN TO 8 MILES SOUTH OF GEORGETOWN...MOVING SOUTHEAST AT 20
MPH.

SEVERE THUNDERSTORMS WILL BE NEAR...
  7 MILES NORTHWEST OF MILLVILLE AND 9 MILES NORTHWEST OF OCEAN VIEW
  BY 300 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

PLEASE REPORT HAIL OR STRONG WINDS TO THE NATIONAL WEATHER SERVICE BY
CALLING TOLL FREE...1-877-633-6772...WHEN YOU CAN DO SO SAFELY.

&&

LAT...LON 3863 7528 3867 7514 3866 7509 3866 7507
      3867 7506 3866 7505 3866 7506 3860 7504
      3859 7505 3851 7504 3851 7505
TIME...MOT...LOC 1847Z 026DEG 17KT 3866 7520 3857 7535

$$

TFG

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 9, 12:34 PM EDT	Special Weather Statement	PHI	Kent	56 min
Aug 9, 1:04 PM EDT	Severe Thunderstorm Warning	PHI	Kent	23 min
Aug 9, 1:17 PM EDT	Severe Thunderstorm Warning	PHI	Sussex	43 min
Aug 9, 1:39 PM EDT	Special Weather Statement	PHI	Kent	66 min
Aug 9, 2:04 PM EDT	Special Weather Statement	PHI	Kent	56 min
Aug 9, 2:19 PM EDT	Severe Thunderstorm Warning	PHI	Sussex	56 min
Aug 9, 2:23 PM EDT	Special Weather Statement	PHI	Sussex	52 min
Aug 9, 3:17 PM EDT	Special Weather Statement	PHI	Sussex	88 min
Aug 9, 3:42 PM EDT	Areal Flood Advisory	PHI	Sussex	119 min

Nearby

Severe Thunderstorm Warnings in Delaware, 2012 Every severe thunderstorm warning in 2012

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.