Alert archive / Maryland / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 19, NWS Philadelphia/Mount Holly

April 24, 20115 counties in Maryland

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Apr 24, 2011, 4:56 PM EDT for 5 counties in Maryland. It was in force for 64 min. 2 reports 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
Apr 24, 2011, 4:56 PM EDT (20:56 UTC)
Expired
Apr 24, 2011, 6:00 PM EDT
In force
64 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon

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

The radar

The Dover AFB radar (KDOX), 71 km from the middle of the area, began a volume at 20:59 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
Apr 24, 5:53 PM EDTHAIL 0.75Centreville, MDPEA TO DIME SIZE HAIL REPORTED.
Apr 24, 6:05 PM EDTHAIL 0.25Centreville, MDPEA SIZE HAIL REPORTED.

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
Apr 24, 3:40 PM EDTSevere Thunderstorm WatchSPC5 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 8.9 hours before the alert went out and 107 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 2011-04-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 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, Washington/Dulle, VA at 12:00Z on 2011-04-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -16 square meters per square second.193958Sfc1 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
1135 m above ground
0-6 km bulk shear
42 kt
0-1 km storm-relative helicity
-16 m²/s²
0-3 km storm-relative helicity
32 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.

652 
WUUS51 KPHI 242056
SVRPHI
MDC011-015-029-035-041-242200-
/O.NEW.KPHI.SV.W.0019.110424T2056Z-110424T2200Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
456 PM EDT SUN APR 24 2011

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

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

* UNTIL 600 PM EDT

* AT 455 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
  BETWEEN BALTIMORE AND WASHINGTON...AND IT WAS MOVING EAST AT 50 
  MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  ROCK HALL AROUND 515 PM EDT...
  LANGFORD AND NEWTOWN AROUND 520 PM EDT...
  CHESTERTOWN AROUND 525 PM EDT...
  MORGNEC AND KENNEDYVILLE AROUND 530 PM EDT...
  CRUMPTON AROUND 535 PM EDT...
  MILLINGTON...MASSEY AND SUDLERSVILLE AROUND 540 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.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 PM EDT THIS 
EVENING FOR DELAWARE AND NORTHEASTERN MARYLAND AND NEW JERSEY AND 
SOUTHEAST PENNSYLVANIA.

&&

LAT...LON 3905 7631 3900 7627 3898 7621 3900 7618
      3903 7625 3910 7624 3916 7628 3934 7618
      3942 7602 3953 7600 3956 7609 3964 7579
      3882 7573 3889 7621 3894 7624 3890 7624
      3893 7628 3890 7629 3891 7638
TIME...MOT...LOC 2054Z 263DEG 45KT 3919 7659

$$

IOVINO
1 follow-up statement
754 
WWUS51 KPHI 242119
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
519 PM EDT SUN APR 24 2011

MDC011-015-029-035-041-242200-
/O.CON.KPHI.SV.W.0019.000000T0000Z-110424T2200Z/
CAROLINE MD-CECIL MD-KENT MD-QUEEN ANNE'S MD-TALBOT MD-
519 PM EDT SUN APR 24 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 600 PM EDT
FOR NORTHEASTERN TALBOT...QUEEN ANNE'S...KENT...SOUTHERN CECIL AND
NORTHERN CAROLINE COUNTIES...

AT 518 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 
PASSING ACROSS CHESAPEAKE BAY.  IT WAS MOVING EAST AT 50 MPH.

THE SEVERE THUNDERSTORM WILL BE NEAR...
  CHESTERTOWN AND KINGSTOWN BY 525 PM EDT...
  MORGNEC AND KENNEDYVILLE BY 530 PM EDT...
  CRUMPTON BY 535 PM EDT...
  MILLINGTON...MASSEY...SUDLERSVILLE AND GALENA BY 540 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH PREPARE 
IMMEDIATELY FOR DAMAGING WINDS...LARGE 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 900 PM EDT SUNDAY
EVENING FOR DELAWARE AND NORTHEASTERN MARYLAND AND NEW JERSEY AND
SOUTHEAST PENNSYLVANIA.

&&

LAT...LON 3905 7631 3900 7627 3898 7621 3900 7618
      3903 7625 3910 7624 3916 7628 3934 7618
      3942 7602 3953 7600 3956 7609 3964 7579
      3882 7573 3889 7621 3894 7624 3890 7624
      3893 7628 3890 7629 3891 7638
TIME...MOT...LOC 2118Z 263DEG 45KT 3922 7620

$$

IOVINO

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 24, 4:08 PM EDTSpecial Weather StatementPHICaroline, Cecil, Kent, Queen Anne's, Talbot52 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.