Alert archive / Maryland / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 8, NWS Philadelphia/Mount Holly

February 25, 20114 counties in Maryland

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Feb 25, 2011, 2:19 PM EST for 4 counties in Maryland. 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
Feb 25, 2011, 2:19 PM EST (19:19 UTC)
Expired
Feb 25, 2011, 3:15 PM EST
In force
56 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon

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

The radar

The Dover AFB radar (KDOX), 69 km from the middle of the area, began a volume at 19:20 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Feb 25, 12:19 PM ESTSevere Thunderstorm WatchSPC3 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 7.3 hours before the alert went out and 102 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, Washington/Dulle, VA at 12:00Z on 2011-02-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Washington/Dulle, VA at 12:00Z on 2011-02-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 557 square meters per square second.1939587897Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
482 m above ground
0-6 km bulk shear
68 kt
0-1 km storm-relative helicity
557 m²/s²
0-3 km storm-relative helicity
622 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.

711 
WUUS51 KPHI 251919
SVRPHI
MDC011-029-035-041-252015-
/O.NEW.KPHI.SV.W.0008.110225T1919Z-110225T2015Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
219 PM EST FRI FEB 25 2011

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHWESTERN CAROLINE COUNTY IN EASTERN MARYLAND...
  TALBOT COUNTY IN EASTERN MARYLAND...
  THIS INCLUDES THE CITY OF EASTON...
  SOUTHWESTERN KENT COUNTY IN NORTHEAST MARYLAND...
  SOUTHWESTERN QUEEN ANNE'S COUNTY IN NORTHEAST MARYLAND...

* UNTIL 315 PM EST

* AT 216 PM EST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING WINDS IN
  EXCESS OF 60 MPH.  THESE STORMS WERE LOCATED ALONG A LINE EXTENDING
  FROM TALBOT TO 41 MILES SOUTHWEST OF TILGHMAN ISLAND...OR ALONG A
  LINE EXTENDING FROM 11 MILES NORTHWEST OF EASTON TO 54 MILES
  SOUTHWEST OF EASTON...AND MOVING SOUTHEAST AT 45 MPH.

* SEVERE THUNDERSTORMS WILL BE NEAR...
  EASTON AND OXFORD AROUND 230 PM EST...
  WINDYHILL...TANYARD...HAMBLETON AND TRAPPE AROUND 235 PM EST...
  CHOPTANK AROUND 240 PM EST...

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.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 400 PM EST FRIDAY
AFTERNOON FOR DELAWARE AND NORTHEASTERN MARYLAND AND SOUTHERN NEW
JERSEY AND SOUTHEAST PENNSYLVANIA.

&&

LAT...LON 3873 7625 3866 7635 3876 7640 3887 7626
      3882 7621 3883 7620 3894 7624 3890 7624
      3893 7628 3884 7638 3885 7639 3905 7631
      3900 7627 3900 7618 3903 7625 3912 7622
      3868 7590 3858 7600 3856 7604
TIME...MOT...LOC 1919Z 314DEG 49KT 3884 7620 3840 7692

$$

NIERENBERG

The office that day

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

IssuedProductOfficeCountiesLasted
Feb 25, 3:59 AM ESTCoastal Flood AdvisoryPHICaroline, Kent, Queen Anne's, Talbot10 hr
Feb 25, 12:44 PM ESTSpecial Weather StatementPHICecil61 min
Feb 25, 1:36 PM ESTSevere Thunderstorm WarningPHICaroline, Queen Anne's, Talbot54 min
Feb 25, 1:55 PM ESTSevere Thunderstorm WarningPHICecil, Kent, Queen Anne's65 min

Nearby

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