Alert archive / Maryland / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 306, NWS Philadelphia/Mount Holly

September 28, 2011Kent County, Delaware; Caroline County, Queen Anne's County, Maryland

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Sep 28, 2011, 1:58 PM EDT for Kent County, Delaware; Caroline County, Queen Anne's County, Maryland. It was in force for 62 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: Sep 28, 2011, 1:58 PM EDT (17:58 UTC)
Expired: Sep 28, 2011, 3:00 PM EDT
In force: 62 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon

Counties Kent County, DE, Caroline County, MD, Queen Anne's County, MD

The radar

The Dover AFB radar (KDOX), 34 km from the middle of the area, began a volume at 18:01 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

Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 6.0 hours before the alert went out and 65 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: 822 J/kg
Mixed-layer CIN: -16 J/kg
Mixed-layer LCL: 526 m above ground
0-6 km bulk shear: 22 kt
0-1 km storm-relative helicity: 34 m²/s²
0-3 km storm-relative helicity: 65 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.5

Open this sounding in Storm Lab

The text

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

904 
WUUS51 KPHI 281758
SVRPHI
DEC001-MDC011-035-281900-
/O.NEW.KPHI.SV.W.0306.110928T1758Z-110928T1900Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
158 PM EDT WED SEP 28 2011

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  WESTERN KENT COUNTY IN CENTRAL DELAWARE...
  THIS INCLUDES THE CITY OF DOVER...
  CAROLINE COUNTY IN EASTERN MARYLAND...
  NORTHEASTERN QUEEN ANNE'S COUNTY IN NORTHEAST MARYLAND...

* UNTIL 300 PM EDT

* AT 155 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
  HARMONY...OR 13 MILES EAST OF EASTON...AND MOVING NORTH AT 20 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  GRIFFIN AROUND 205 PM EDT...
  DENTON AROUND 210 PM EDT...
  6 MILES EAST OF RIDGELY AROUND 220 PM EDT...
  GREENSBORO AROUND 230 PM EDT...
  SANDTOWN AND GOLDSBORO AROUND 245 PM EDT...
  HAZLETTVILLE AND HARTLY AROUND 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.

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 3876 7596 3879 7595 3881 7590 3885 7593
      3926 7583 3925 7581 3925 7579 3919 7549
      3883 7571 3883 7573 3881 7572 3873 7577
TIME...MOT...LOC 1758Z 197DEG 18KT 3881 7582

$$

HAYES

4 follow-up statements

993 
WWUS51 KPHI 281816
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
216 PM EDT WED SEP 28 2011

DEC001-MDC011-035-281900-
/O.CON.KPHI.SV.W.0306.000000T0000Z-110928T1900Z/
KENT DE-CAROLINE MD-QUEEN ANNE'S MD-
216 PM EDT WED SEP 28 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 300 PM EDT
FOR NORTHEASTERN QUEEN ANNE'S...NORTHERN CAROLINE AND WESTERN KENT
COUNTIES...

AT 212 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 RIDGELY...OR 14 MILES SOUTHEAST OF CENTERVILLE...MOVING
NORTH AT 25 MPH.

THE SEVERE THUNDERSTORM WILL BE NEAR...
  GOLDSBORO AND 6 MILES WEST OF SANDTOWN BY 230 PM EDT...
  HENDERSON BY 240 PM EDT...
  MARYDEL BY 245 PM EDT...
  TEMPLEVILLE BY 250 PM EDT...
  6 MILES WEST OF HARTLY BY 255 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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 3886 7592 3926 7583 3925 7581 3925 7579
      3919 7549 3884 7571
TIME...MOT...LOC 1816Z 185DEG 22KT 3895 7584

$$

HAYES

495 
WWUS51 KPHI 281830
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
230 PM EDT WED SEP 28 2011

DEC001-MDC011-035-281900-
/O.CON.KPHI.SV.W.0306.000000T0000Z-110928T1900Z/
KENT DE-CAROLINE MD-QUEEN ANNE'S MD-
230 PM EDT WED SEP 28 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 300 PM EDT
FOR NORTHEASTERN QUEEN ANNE'S...NORTHERN CAROLINE AND WESTERN KENT
COUNTIES...

AT 225 PM EDT...A SEVERE THUNDERSTORM WAS REPORTED CAPABLE OF
PRODUCING QUARTER SIZE HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.
THIS STORM WAS LOCATED NEAR OAKLAND...OR 12 MILES EAST OF 
CENTERVILLE...MOVING NORTH AT 25 MPH.

THE SEVERE THUNDERSTORM WILL BE NEAR...
  HENDERSON BY 240 PM EDT...
  MARYDEL BY 245 PM EDT...
  TEMPLEVILLE BY 250 PM EDT...
  6 MILES WEST OF HARTLY BY 255 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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 3886 7592 3926 7583 3925 7581 3925 7579
      3919 7549 3884 7571
TIME...MOT...LOC 1829Z 185DEG 22KT 3903 7584

$$

HAYES

296 
WWUS51 KPHI 281845
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
245 PM EDT WED SEP 28 2011

DEC001-MDC011-035-281900-
/O.CON.KPHI.SV.W.0306.000000T0000Z-110928T1900Z/
KENT DE-CAROLINE MD-QUEEN ANNE'S MD-
245 PM EDT WED SEP 28 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 300 PM EDT
FOR NORTHEASTERN QUEEN ANNE'S...NORTHERN CAROLINE AND WEST CENTRAL
KENT COUNTIES...

AT 242 PM EDT...A SEVERE THUNDERSTORM WAS REPORTED CAPABLE OF
PRODUCING QUARTER SIZE HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.
THIS STORM WAS LOCATED NEAR TEMPLEVILLE...OR 15 MILES NORTHEAST OF 
CENTERVILLE...MOVING NORTH AT 25 MPH.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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 3886 7592 3926 7583 3925 7581 3925 7579
      3924 7573 3923 7569 3885 7577
TIME...MOT...LOC 1845Z 192DEG 48KT 3918 7581

$$

HAYES

428 
WWUS51 KPHI 281857
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
257 PM EDT WED SEP 28 2011

DEC001-MDC011-035-281907-
/O.EXP.KPHI.SV.W.0306.000000T0000Z-110928T1900Z/
KENT DE-CAROLINE MD-QUEEN ANNE'S MD-
257 PM EDT WED SEP 28 2011

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN QUEEN ANNE'S...
NORTHERN CAROLINE AND WEST CENTRAL KENT COUNTIES WILL EXPIRE AT 300
PM EDT...

THE STORM THAT PROMPTED THE WARNING HAS WEAKENED AND IS MOVING OUT 
OF THE AREA.

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 3886 7592 3926 7583 3925 7581 3925 7579
      3924 7573 3923 7569 3885 7577
TIME...MOT...LOC 1857Z 192DEG 48KT 3934 7577

$$

HAYES

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 27, 11:53 PM EDT	Coastal Flood Statement	PHI	New Castle	4 hr
Sep 28, 4:10 AM EDT	Coastal Flood Advisory	PHI	Kent, Sussex	7 hr
Sep 28, 8:30 AM EDT	Special Weather Statement	PHI	Sussex	2 hr
Sep 28, 9:10 AM EDT	Special Weather Statement	PHI	Sussex	35 min
Sep 28, 9:32 AM EDT	Areal Flood Advisory	PHI	Kent, Sussex	3 hr
Sep 28, 10:02 AM EDT	Coastal Flood Statement	PHI	New Castle	8 hr
Sep 28, 10:05 AM EDT	Special Weather Statement	PHI	Kent	40 min
Sep 28, 10:45 AM EDT	Special Weather Statement	PHI	Kent	60 min
Sep 28, 1:31 PM EDT	Special Weather Statement	PHI	Sussex	59 min
Sep 28, 2:14 PM EDT	Areal Flood Advisory	PHI	Kent, Sussex	2 hr
Sep 28, 2:41 PM EDT	Special Weather Statement	PHI	Kent	64 min
Sep 28, 2:59 PM EDT	Special Weather Statement	PHI	New Castle	61 min
Sep 28, 3:29 PM EDT	Coastal Flood Statement	PHI	Kent, Sussex	9 hr
Sep 28, 3:54 PM EDT	Special Weather Statement	PHI	Kent, New Castle	66 min
Sep 28, 1:40 PM EDT	Special Weather Statement	PHI	Caroline, Kent, Queen Anne's	65 min

Nearby

Severe Thunderstorm Warnings in Maryland, 2011 Severe Thunderstorm Warnings in Delaware, 2011 Every 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.