Alert archive / Maryland / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 230, NWS Philadelphia/Mount Holly

August 1, 2011Caroline County, Queen Anne's County, Talbot County, Maryland

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 1, 2011, 6:41 PM EDT for Caroline County, Queen Anne's County, Talbot County, Maryland. It was in force for 18 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 1, 2011, 6:41 PM EDT (22:41 UTC)
Expired
Aug 1, 2011, 6:59 PM EDT
In force
18 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon

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

The nearest sounding before it

Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 10.7 hours before the alert went out and 75 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, Phillips Aaf/Abe, MD at 12:00Z on 2011-08-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 307 joules per kilogram.LCLLFCEL10008507005003002001001 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, Phillips Aaf/Abe, MD at 12:00Z on 2011-08-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -192 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
307 J/kg
Mixed-layer CIN
-150 J/kg
Mixed-layer LCL
1512 m above ground
0-6 km bulk shear
23 kt
0-1 km storm-relative helicity
-192 m²/s²
0-3 km storm-relative helicity
-166 m²/s²
Significant tornado parameter
0.0
Supercell composite
-1.5

Open this sounding in Storm Lab

The text

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

672 
WUUS51 KPHI 012241
SVRPHI
MDC011-035-041-020000-
/O.NEW.KPHI.SV.W.0230.110801T2241Z-110802T0000Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
641 PM EDT MON AUG 1 2011

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

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

* UNTIL 800 PM EDT

* AT 638 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  A DEVELOPING SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE 
  HAIL...AND   DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS   
  LOCATED NEAR   STARR...OR NEAR CENTERVILLE...AND MOVING SOUTHEAST  
  AT 15 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  SKIPTON AROUND 655 PM EDT...
  JUMPTOWN AND SKIPTON AROUND 700 PM EDT...
  QUEEN ANNE AND RIDGELY AROUND 705 PM EDT...
  CORDOVA AROUND 710 PM EDT...
  GRIFFIN AROUND 720 PM EDT...
  MATTHEWS AND DENTON AROUND 725 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 3903 7616 3907 7610 3911 7602 3884 7572
      3878 7572 3872 7572 3870 7574 3867 7580
      3869 7582 3869 7586 3867 7595 3858 7600
TIME...MOT...LOC 2241Z 325DEG 14KT 3899 7603

$$

TFG
1 follow-up statement
439 
WWUS51 KPHI 012259
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
659 PM EDT MON AUG 1 2011

MDC011-035-041-012309-
/O.CAN.KPHI.SV.W.0230.000000T0000Z-110802T0000Z/
CAROLINE MD-QUEEN ANNE'S MD-TALBOT MD-
659 PM EDT MON AUG 1 2011

...THE SEVERE THUNDERSTORM WARNING FOR EASTERN TALBOT...CENTRAL QUEEN
ANNE'S AND CAROLINE COUNTIES IS CANCELLED...

THE THUNDERSTORM HAS WEAKENED BELOW SEVERE LIMITS.

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 3903 7616 3907 7610 3911 7602 3884 7572
      3878 7572 3872 7572 3870 7574 3867 7580
      3869 7582 3869 7586 3867 7595 3858 7600
TIME...MOT...LOC 2259Z 325DEG 14KT 3893 7598

$$
 
TFG

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 1, 4:07 PM EDTSpecial Weather StatementPHICecil53 min
Aug 1, 4:46 PM EDTSevere Thunderstorm WarningPHICecil48 min
Aug 1, 5:12 PM EDTSevere Thunderstorm WarningPHICecil, Kent, Queen Anne's78 min
Aug 1, 6:12 PM EDTAreal Flood AdvisoryPHIKent, Queen Anne's2 hr
Aug 1, 7:31 PM EDTSpecial Weather StatementPHICaroline, Cecil, Kent, Queen Anne's119 min
Aug 1, 7:46 PM EDTSevere Thunderstorm WarningPHICaroline, Kent, Queen Anne's38 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.