Alert archive / Maryland / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 278, NWS Philadelphia/Mount Holly

August 19, 2011Cecil County, Kent County, Queen Anne's County, Maryland

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 19, 2011, 6:21 PM EDT for Cecil County, Kent County, Queen Anne's County, Maryland. It was in force for 69 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 19, 2011, 6:21 PM EDT (22:21 UTC)
Expired: Aug 19, 2011, 7:30 PM EDT
In force: 69 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon

Counties Cecil County, MD, Kent County, MD, Queen Anne's County, MD

The radar

The Dover AFB radar (KDOX), 77 km from the middle of the area, began a volume at 22:22 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, 10.4 hours before the alert went out and 53 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: 146 J/kg
Mixed-layer CIN: -154 J/kg
Mixed-layer LCL: 1250 m above ground
0-6 km bulk shear: 19 kt
0-1 km storm-relative helicity: 359 m²/s²
0-3 km storm-relative helicity: 370 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.

171 
WUUS51 KPHI 192221
SVRPHI
MDC015-029-035-192330-
/O.NEW.KPHI.SV.W.0278.110819T2221Z-110819T2330Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
621 PM EDT FRI AUG 19 2011

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHERN CECIL COUNTY IN NORTHEAST MARYLAND...
  KENT COUNTY IN NORTHEAST MARYLAND...
  QUEEN ANNE'S COUNTY IN NORTHEAST MARYLAND...
  THIS INCLUDES THE CITY OF CENTERVILLE...

* UNTIL 730 PM EDT

* AT 618 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING QUARTER SIZE
  HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.  THESE STORMS WERE
  LOCATED ALONG A LINE EXTENDING FROM 6 MILES SOUTHWEST OF ROCK HALL
  TO 8 MILES WEST OF NEWTOWN TO 9 MILES WEST OF CHARLESTOWN...OR
  ALONG A LINE EXTENDING FROM 15 MILES WEST OF CENTERVILLE TO 17
  MILES EAST OF BALTIMORE TO 18 MILES WEST OF ELKTON...AND MOVING
  SOUTHEAST AT 25 MPH.

* SEVERE THUNDERSTORMS WILL BE NEAR...
  ROCK HALL AROUND 630 PM EDT...
  CHARLESTOWN AROUND 635 PM EDT...
  OVERTON AND NEWTOWN AROUND 640 PM EDT...
  LANGFORD AND BETTERTON AROUND 645 PM EDT...
  OLD TOWN AND HOLLYWOOD BEACH AROUND 650 PM EDT...
  CHESTERTOWN AROUND 655 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.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 PM EDT FRIDAY
EVENING FOR NORTHERN DELAWARE AND NEW JERSEY AND EASTERN
PENNSYLVANIA.

&&

LAT...LON 3905 7631 3903 7625 3906 7623 3916 7628
      3932 7619 3938 7611 3938 7607 3944 7600
      3953 7599 3954 7607 3961 7613 3962 7612
      3954 7578 3934 7577 3894 7596 3898 7619
      3901 7619 3904 7627 3900 7629 3901 7634
TIME...MOT...LOC 2222Z 304DEG 21KT 3909 7631 3934 7627
          3956 7612

$$

TFG

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 18, 8:35 PM EDT	Special Weather Statement	PHI	Queen Anne's	55 min
Aug 19, 12:02 AM EDT	Special Weather Statement	PHI	Cecil	58 min
Aug 19, 1:00 AM EDT	Special Weather Statement	PHI	Cecil	45 min
Aug 19, 1:14 AM EDT	Areal Flood Advisory	PHI	Cecil, Kent	3 hr
Aug 19, 1:44 AM EDT	Special Weather Statement	PHI	Cecil, Kent, Queen Anne's	61 min
Aug 19, 4:09 PM EDT	Severe Thunderstorm Warning	PHI	Caroline, Queen Anne's	66 min
Aug 19, 4:42 PM EDT	Severe Thunderstorm Warning	PHI	Caroline	63 min
Aug 19, 4:53 PM EDT	Areal Flood Advisory	PHI	Caroline, Cecil, Kent, Queen Anne's	5 hr
Aug 19, 5:35 PM EDT	Severe Thunderstorm Warning	PHI	Cecil	55 min
Aug 19, 5:39 PM EDT	Areal Flood Advisory	PHI	Cecil	3 hr
Aug 19, 6:14 PM EDT	Severe Thunderstorm Warning	PHI	Cecil	65 min
Aug 19, 6:18 PM EDT	Areal Flood Advisory	PHI	Caroline, Kent, Queen Anne's, Talbot	3 hr
Aug 19, 6:34 PM EDT	Areal Flood Advisory	PHI	Caroline	2 hr

Nearby

Severe Thunderstorm Warnings in Maryland, 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.