Alert archive / Delaware / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 180, NWS Philadelphia/Mount Holly

August 9, 2012Sussex County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 9, 2012, 2:19 PM EDT for Sussex County, Delaware. It was in force for 56 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 9, 2012, 2:19 PM EDT (18:19 UTC)
Expired
Aug 9, 2012, 3:15 PM EDT
In force
56 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon

County Sussex County, DE

The radar

The Dover AFB radar (KDOX), 42 km from the middle of the area, began a volume at 18:20 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 12:00Z, 6.3 hours before the alert went out and 67 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 2012-08-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2382 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 2012-08-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 5 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
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.

584 
WUUS51 KPHI 091819
SVRPHI
DEC005-091915-
/O.NEW.KPHI.SV.W.0180.120809T1819Z-120809T1915Z/

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

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

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

* UNTIL 315 PM EDT

* AT 216 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM.  THIS STORM WAS LOCATED NEAR 
  SELBYVILLE...OR   17 MILES SOUTHEAST OF GEORGETOWN...AND MOVING EAST 
  AT 10 MPH. A SECOND INTENSIFYING STORM WHICH MIGHT ALSO BECOME
  SEVERE IS NEAR MILLSBORO. 

* THE FIRST SEVERE THUNDERSTORM WILL BE NEAR...
  MILLVILLE AROUND 300 PM EDT...
  FENWICK ISLAND AROUND 310 PM EDT...
  BETHANY BEACH AROUND 315 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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 3852 7534 3864 7533 3853 7504 3852 7504
      3845 7504 3844 7505 3844 7532
TIME...MOT...LOC 1818Z 254DEG 8KT 3848 7522

$$
 
TFG
1 follow-up statement
834 
WWUS51 KPHI 091857
SVSPHI

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

DEC005-091915-
/O.CON.KPHI.SV.W.0180.000000T0000Z-120809T1915Z/
SUSSEX DE-
257 PM EDT THU AUG 9 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 315 PM EDT
FOR SOUTHEASTERN SUSSEX COUNTY...

AT 253 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING QUARTER
SIZE HAIL...AND DAMAGING WINDS TO 60 MPH.  THESE STORMS
WERE LOCATED ALONG A LINE EXTENDING FROM DAGSBORO TO FRANKFORD...OR
ALONG A LINE EXTENDING FROM 11 MILES SOUTHEAST OF GEORGETOWN TO 15
MILES SOUTH OF GEORGETOWN...MOVING SOUTHEAST AT 10 MPH.

SEVERE THUNDERSTORMS WILL BE NEAR...
  FRANKFORD BY 310 PM EDT...
  SELBYVILLE...MILLVILLE...6 MILES WEST OF OCEAN VIEW AND 7 MILES
  WEST OF BETHANY BEACH BY 315 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 3854 7531 3861 7526 3853 7504 3845 7504
      3844 7505 3844 7532
TIME...MOT...LOC 1857Z 323DEG 7KT 3859 7522 3848 7530

$$

TFG

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 9, 12:34 PM EDTSpecial Weather StatementPHIKent56 min
Aug 9, 1:04 PM EDTSevere Thunderstorm WarningPHIKent23 min
Aug 9, 1:17 PM EDTSevere Thunderstorm WarningPHISussex43 min
Aug 9, 1:39 PM EDTSpecial Weather StatementPHIKent66 min
Aug 9, 1:55 PM EDTSevere Thunderstorm WarningPHISussex65 min
Aug 9, 2:04 PM EDTSpecial Weather StatementPHIKent56 min
Aug 9, 2:23 PM EDTSpecial Weather StatementPHISussex52 min
Aug 9, 3:17 PM EDTSpecial Weather StatementPHISussex88 min
Aug 9, 3:42 PM EDTAreal Flood AdvisoryPHISussex119 min

Nearby

Severe Thunderstorm Warnings in Delaware, 2012Every 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.