Alert archive / Maryland / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 100, NWS Philadelphia/Mount Holly

June 9, 2011Cecil County, Kent County, Queen Anne's County, Maryland

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jun 9, 2011, 8:45 PM EDT for Cecil County, Kent County, Queen Anne's County, Maryland. It was in force for 60 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
Jun 9, 2011, 8:45 PM EDT (00:45 UTC)
Expired
Jun 9, 2011, 9:45 PM EDT
In force
60 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), 70 km from the middle of the area, began a volume at 00:47 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
Jun 9, 9:00 PM EDTTSTM WND DMGTolchester, MDTREES DOWN.

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
Jun 9, 2:34 PM EDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 00:00Z, 0.8 hours before the alert went out and 119 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 00:00Z on 2011-06-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1601 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 00:00Z on 2011-06-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 18 square meters per square second.1939Sfc1 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
1601 J/kg
Mixed-layer CIN
-110 J/kg
Mixed-layer LCL
1529 m above ground
0-6 km bulk shear
10 kt
0-1 km storm-relative helicity
18 m²/s²
0-3 km storm-relative helicity
65 m²/s²
Significant tornado parameter
-0.1
Supercell composite
-1.2

Open this sounding in Storm Lab

The text

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

150 
WUUS51 KPHI 100045
SVRPHI
MDC015-029-035-100145-
/O.NEW.KPHI.SV.W.0100.110610T0045Z-110610T0145Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
845 PM EDT THU JUN 9 2011

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

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

* UNTIL 945 PM EDT

* AT 843 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 11
  MILES NORTHWEST OF ROCK HALL...OR 11 MILES SOUTHEAST OF
  BALTIMORE...AND MOVING EAST AT 30 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  NEWTOWN AND LANGFORD AROUND 915 PM EDT...
  CHESTERTOWN AROUND 920 PM EDT...
  MORGNEC AND KENNEDYVILLE AROUND 930 PM EDT...
  CRUMPTON AROUND 940 PM EDT...
  MILLINGTON AND MASSEY AROUND 945 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 1000 PM EDT
THURSDAY EVENING FOR NORTHERN DELAWARE AND NORTHEAST MARYLAND AND NEW
JERSEY AND SOUTHEAST PENNSYLVANIA.

&&

LAT...LON 3934 7618 3934 7615 3938 7611 3938 7607
      3939 7605 3944 7578 3915 7577 3912 7584
      3907 7586 3900 7594 3906 7624 3914 7626
      3915 7628 3916 7628
TIME...MOT...LOC 0045Z 263DEG 25KT 3923 7640

$$

AMC
2 follow-up statements
099 
WWUS51 KPHI 100109
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
909 PM EDT THU JUN 9 2011

MDC015-029-035-100145-
/O.CON.KPHI.SV.W.0100.000000T0000Z-110610T0145Z/
CECIL MD-KENT MD-QUEEN ANNE'S MD-
909 PM EDT THU JUN 9 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 945 PM EDT
FOR NORTHERN QUEEN ANNE'S...KENT AND SOUTHEASTERN CECIL COUNTIES...

AT 907 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
LOCATED NEAR LANGFORD...OR 14 MILES NORTHWEST OF CENTERVILLE...MOVING
EAST AT 30 MPH.

THE SEVERE THUNDERSTORM WILL BE NEAR...
  LANGFORD AND OLD TOWN BY 915 PM EDT...
  CHESTERTOWN BY 920 PM EDT...
  KINGSTOWN BY 925 PM EDT...
  MORGNEC AND KENNEDYVILLE BY 930 PM EDT...
  CRUMPTON BY 940 PM EDT...
  MILLINGTON AND SUDLERSVILLE BY 945 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 1000 PM EDT
THURSDAY EVENING FOR NORTHERN DELAWARE AND NORTHEAST MARYLAND AND NEW
JERSEY AND SOUTHEAST PENNSYLVANIA.

&&

LAT...LON 3934 7618 3934 7615 3938 7611 3938 7607
      3939 7605 3944 7578 3915 7577 3912 7584
      3907 7586 3900 7594 3906 7624 3914 7626
      3915 7628 3916 7628
TIME...MOT...LOC 0109Z 263DEG 25KT 3921 7618

$$

AMC
333 
WWUS51 KPHI 100132
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
932 PM EDT THU JUN 9 2011

MDC015-029-035-100145-
/O.CON.KPHI.SV.W.0100.000000T0000Z-110610T0145Z/
CECIL MD-KENT MD-QUEEN ANNE'S MD-
932 PM EDT THU JUN 9 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 945 PM EDT
FOR NORTHEASTERN QUEEN ANNE'S...KENT AND SOUTHEASTERN CECIL
COUNTIES...

AT 930 PM EDT...A SEVERE THUNDERSTORM WAS REPORTED CAPABLE OF
PRODUCING QUARTER SIZE HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.
 THIS STORM WAS LOCATED NEAR MORGNEC...OR 13 MILES NORTH OF
CENTERVILLE...MOVING EAST AT 30 MPH.

THE SEVERE THUNDERSTORM WILL BE NEAR...
  CRUMPTON AND SUDLERSVILLE BY 940 PM EDT...
  MILLINGTON...MASSEY...7 MILES NORTH OF BARCLAY AND 7 MILES SOUTH OF
  GALENA BY 945 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.

&&

LAT...LON 3938 7611 3938 7607 3939 7605 3944 7578
      3915 7577 3912 7584 3907 7586 3900 7594
      3910 7603 3918 7606 3931 7615
TIME...MOT...LOC 0132Z 263DEG 25KT 3923 7597

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 9, 11:29 PM EDTSpecial Weather StatementPHIQueen Anne's61 min
Jun 9, 11:46 PM EDTSevere Thunderstorm WarningPHIKent, Queen Anne's, Talbot59 min
Jun 10, 12:16 AM EDTSevere Thunderstorm WarningPHICaroline, Kent, Queen Anne's, Talbot59 min
Jun 10, 1:01 AM EDTSpecial Weather StatementPHICaroline, Queen Anne's, Talbot119 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.