Alert archive / Delaware / Severe Thunderstorm Warnings in 2011
Severe Thunderstorm Warning 239, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 14, 2011, 11:47 AM EDT for Kent County, Delaware. It was in force for 28 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 14, 2011, 11:47 AM EDT (15:47 UTC)
- Expired
- Aug 14, 2011, 12:15 PM EDT
- In force
- 28 min
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
County Kent County, DE
The radar
The Dover AFB radar (KDOX), 42 km from the middle of the area, began a volume at 15:50 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 14, 11:50 AM EDT | TSTM WND DMG | Dover, DE | TREES REPORTED 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, 3.8 hours before the alert went out and 142 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.
- Mixed-layer CAPE
- 341 J/kg
- Mixed-layer CIN
- -8 J/kg
- Mixed-layer LCL
- 931 m above ground
- 0-6 km bulk shear
- 21 kt
- 0-1 km storm-relative helicity
- 52 m²/s²
- 0-3 km storm-relative helicity
- 81 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.5
The text
As transmitted, in the capitals the NWS used until 2016.
457
WUUS51 KPHI 141547
SVRPHI
DEC001-141615-
/O.NEW.KPHI.SV.W.0239.110814T1547Z-110814T1615Z/
BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1147 AM EDT SUN AUG 14 2011
THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A
* SEVERE THUNDERSTORM WARNING FOR...
NORTHERN KENT COUNTY IN CENTRAL DELAWARE...
THIS INCLUDES THE CITY OF DOVER...
* UNTIL 1215 PM EDT
* AT 1141 AM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS IN
EXCESS OF 60 MPH. THIS STORM WAS LOCATED NEAR CAMDEN AND
DOVER...AND MOVING NORTHEAST AT 20 MPH.
* THE SEVERE THUNDERSTORM WILL BE NEAR...
LITTLE CREEK AND LEIPSIC AROUND NOON EDT...
PRECAUTIONARY/PREPAREDNESS ACTIONS...
DOPPLER RADAR HAS INDICATED SOME WEAK ROTATION WITHIN THIS STORM.
WHILE NOT IMMEDIATELY LIKELY...A TORNADO MAY STILL DEVELOP. IF A
TORNADO IS SPOTTED...ACT QUICKLY AND MOVE TO A PLACE OF SAFETY IN A
STURDY STRUCTURE...SUCH AS A BASEMENT OR SMALL INTERIOR ROOM.
THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...PREPARE
IMMEDIATELY FOR DAMAGING WINDS...HAIL...AND DEADLY 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 3916 7569 3933 7545 3932 7544 3931 7544
3924 7538 3920 7539 3917 7540 3910 7539
3902 7554
TIME...MOT...LOC 1546Z 230DEG 17KT 3914 7552
$$
IOVINO1 follow-up statement
598
WWUS51 KPHI 141604
SVSPHI
SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1204 PM EDT SUN AUG 14 2011
DEC001-141615-
/O.CON.KPHI.SV.W.0239.000000T0000Z-110814T1615Z/
KENT DE-
1204 PM EDT SUN AUG 14 2011
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1215 PM EDT
FOR NORTHERN KENT COUNTY...
AT NOON EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS IN
EXCESS OF 60 MPH. THIS STORM WAS LOCATED NEAR LITTLE CREEK AND
DOVER...MOVING NORTHEAST AT 20 MPH.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
DOPPLER RADAR HAS INDICATED SOME WEAK ROTATION WITHIN THIS STORM.
WHILE NOT IMMEDIATELY LIKELY...A TORNADO MAY STILL DEVELOP. IF A
TORNADO IS SPOTTED...ACT QUICKLY AND MOVE TO A PLACE OF SAFETY IN A
STURDY STRUCTURE...SUCH AS A BASEMENT OR SMALL INTERIOR ROOM.
PLEASE REPORT HAIL OR STRONG WINDS TO THE NATIONAL WEATHER SERVICE BY
CALLING TOLL FREE...1-877-633-6772...WHEN YOU CAN DO SO SAFELY.
&&
LAT...LON 3916 7569 3933 7545 3932 7544 3931 7544
3924 7538 3920 7539 3917 7540 3910 7539
3902 7554
TIME...MOT...LOC 1604Z 230DEG 17KT 3919 7544
$$
IOVINOThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 14, 1:51 AM EDT | Areal Flood Advisory | PHI | Kent, New Castle, Sussex | 6 hr |
| Aug 14, 2:27 AM EDT | Flash Flood Warning | PHI | Kent, New Castle, Sussex | 4 hr |
| Aug 14, 3:42 AM EDT | Flash Flood Watch | PHI | Kent, New Castle, Sussex | 25 hr |
| Aug 14, 6:39 AM EDT | River Flood Warning | PHI | New Castle | 13 hr |
| Aug 14, 6:45 AM EDT | Areal Flood Advisory | PHI | Kent, New Castle | 4 hr |
| Aug 14, 7:43 AM EDT | Flash Flood Warning | PHI | Kent, New Castle | 4 hr |
| Aug 14, 11:40 AM EDT | Areal Flood Warning | PHI | Kent, New Castle | 18 hr |
| Aug 14, 2:56 PM EDT | River Flood Warning | PHI | New Castle | 3 hr |
Nearby
Severe Thunderstorm Warnings in Delaware, 2011Every severe thunderstorm warning in 2011
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.