Alert archive / Maryland / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 4, NWS Philadelphia/Mount Holly

February 25, 2011Caroline County, Queen Anne's County, Talbot County, Maryland; Kent County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Feb 25, 2011, 1:36 PM EST for Caroline County, Queen Anne's County, Talbot County, Maryland; Kent County, Delaware. It was in force for 54 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
Feb 25, 2011, 1:36 PM EST (18:36 UTC)
Expired
Feb 25, 2011, 2:30 PM EST
In force
54 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon

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

The radar

The Dover AFB radar (KDOX), 61 km from the middle of the area, began a volume at 18:38 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

TimeReportWhereRemark
Feb 25, 1:50 PM ESTTSTM WND GST 58Sandtown, DE

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

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, 6.6 hours before the alert went out and 110 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.

889 
WUUS51 KPHI 251836
SVRPHI
DEC001-MDC011-035-041-251930-
/O.NEW.KPHI.SV.W.0004.110225T1836Z-110225T1930Z/

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

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

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

* UNTIL 230 PM EST

* AT 134 PM EST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS
  OF 60 MPH.  THIS STORM WAS LOCATED NEAR WYE MILLS...OR 7 MILES
  SOUTHWEST OF CENTERVILLE...AND MOVING EAST AT 45 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  STARR...CARVILLE AND CENTERVILLE AROUND 140 PM EST...
  JUMPTOWN...RIDGELY...QUEEN ANNE AND HOPE AROUND 145 PM EST...
  OAKLAND AROUND 150 PM EST...
  GOLDSBORO AND GREENSBORO AROUND 155 PM EST...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...PREPARE 
IMMEDIATELY FOR DAMAGING WINDS...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 3899 7620 3900 7618 3901 7619 3933 7547
      3897 7535 3880 7625 3886 7627 3882 7620
      3883 7620 3886 7622 3893 7621 3894 7624
      3890 7623 3890 7625 3893 7629 3898 7630
TIME...MOT...LOC 1835Z 256DEG 46KT 3895 7609

$$

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, 1:55 PM ESTSevere Thunderstorm WarningPHICecil, Kent, Queen Anne's65 min
Feb 25, 2:19 PM ESTSevere Thunderstorm WarningPHICaroline, Kent, Queen Anne's, Talbot56 min
Feb 25, 7:53 AM ESTSpecial Weather StatementPHIKent, Sussex82 min
Feb 25, 9:15 AM ESTSpecial Weather StatementPHIKent, Sussex90 min
Feb 25, 10:28 AM ESTSpecial Weather StatementPHISussex62 min
Feb 25, 1:11 PM ESTSevere Thunderstorm WarningPHINew Castle64 min
Feb 25, 2:57 PM ESTSpecial Weather StatementPHIKent63 min

Nearby

Severe Thunderstorm Warnings in Maryland, 2011Severe 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.