Alert archive / Delaware / Severe Thunderstorm Warnings in 2011
Severe Thunderstorm Warning 107, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jun 11, 2011, 4:21 PM EDT for Kent County, New Castle County, Delaware. It was in force for 39 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
- Jun 11, 2011, 4:21 PM EDT (20:21 UTC)
- Expired
- Jun 11, 2011, 5:00 PM EDT
- In force
- 39 min
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
Counties Kent County, DE, New Castle County, DE
The radar
The Dover AFB radar (KDOX), 57 km from the middle of the area, began a volume at 20:21 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 |
|---|---|---|---|
| Jun 11, 4:45 PM EDT | HAIL 0.88 | Clayton, DE |
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, 8.4 hours before the alert went out and 156 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
- 171 J/kg
- Mixed-layer CIN
- -136 J/kg
- Mixed-layer LCL
- 1081 m above ground
- 0-6 km bulk shear
- 14 kt
- 0-1 km storm-relative helicity
- -2 m²/s²
- 0-3 km storm-relative helicity
- 19 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
183 WUUS51 KPHI 112021 SVRPHI DEC001-003-112100- /O.NEW.KPHI.SV.W.0107.110611T2021Z-110611T2100Z/ BULLETIN - EAS ACTIVATION REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 421 PM EDT SAT JUN 11 2011 THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A * SEVERE THUNDERSTORM WARNING FOR... NORTHWESTERN KENT COUNTY IN CENTRAL DELAWARE... SOUTHWESTERN NEW CASTLE COUNTY IN NORTHERN DELAWARE... * UNTIL 500 PM EDT * AT 417 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH. THIS STORM WAS LOCATED NEAR DELANEY CORNER...AND MOVING EAST AT 10 MPH. * THE SEVERE THUNDERSTORM WILL BE NEAR... GREEN SPRING AROUND 445 PM EDT... CLAYTON AROUND 450 PM EDT... SMYRNA AROUND 455 PM EDT... CHESWOLD AROUND 500 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. && LAT...LON 3940 7557 3918 7556 3923 7576 3937 7577 TIME...MOT...LOC 2021Z 275DEG 9KT 3930 7573 $$ IOVINO
1 follow-up statement
424 WWUS51 KPHI 112048 SVSPHI SEVERE WEATHER STATEMENT NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 448 PM EDT SAT JUN 11 2011 DEC001-003-112100- /O.CON.KPHI.SV.W.0107.000000T0000Z-110611T2100Z/ KENT DE-NEW CASTLE DE- 448 PM EDT SAT JUN 11 2011 ...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 500 PM EDT FOR SOUTHWESTERN NEW CASTLE AND NORTHWESTERN KENT COUNTIES... AT 446 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH. THIS STORM WAS LOCATED NEAR CLAYTON...MOVING EAST AT 10 MPH. THE SEVERE THUNDERSTORM WILL BE NEAR... SMYRNA BY 455 PM EDT... CHESWOLD AND 7 MILES SOUTH OF CHAMBERSVILLE BY 500 PM EDT... LAT...LON 3940 7557 3918 7556 3923 7576 3937 7577 TIME...MOT...LOC 2048Z 283DEG 9KT 3927 7564 $$ IOVINO
The office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 11, 5:53 AM EDT | Special Weather Statement | PHI | Kent, Sussex | 67 min |
| Jun 11, 6:17 AM EDT | Special Weather Statement | PHI | New Castle | 58 min |
| Jun 11, 6:34 AM EDT | Special Weather Statement | PHI | Sussex | 56 min |
| Jun 11, 6:52 AM EDT | Areal Flood Advisory | PHI | Sussex | 113 min |
| Jun 11, 2:43 PM EDT | Special Weather Statement | PHI | Sussex | 47 min |
| Jun 11, 3:05 PM EDT | Special Weather Statement | PHI | Sussex | 55 min |
| Jun 11, 4:09 PM EDT | Special Weather Statement | PHI | Sussex | 66 min |
| Jun 11, 4:57 PM EDT | Special Weather Statement | PHI | Kent | 48 min |
| Jun 11, 5:05 PM EDT | Areal Flood Advisory | PHI | Kent | 63 min |
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.