Alert archive / Maryland / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 216, NWS Philadelphia/Mount Holly

September 8, 20124 counties in Maryland

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Sep 8, 2012, 4:30 PM EDT for 4 counties in 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
Sep 8, 2012, 4:30 PM EDT (20:30 UTC)
Expired
Sep 8, 2012, 5:30 PM EDT
In force
60 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), 66 km from the middle of the area, began a volume at 20:31 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
Sep 8, 5:25 PM EDTTSTM WND DMGPreston, MDROOF DAMAGE TO A BUILDING ALONG PAYNE ROAD IN PRESTON.

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
Sep 8, 12:15 PM EDTSevere Thunderstorm WatchSPC9 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 8.5 hours before the alert went out and 105 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 2012-09-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 252 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 2012-09-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 150 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
252 J/kg
Mixed-layer CIN
-81 J/kg
Mixed-layer LCL
638 m above ground
0-6 km bulk shear
39 kt
0-1 km storm-relative helicity
150 m²/s²
0-3 km storm-relative helicity
140 m²/s²
Significant tornado parameter
0.1
Supercell composite
1.0

Open this sounding in Storm Lab

The text

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

204 
WUUS51 KPHI 082030
SVRPHI
MDC011-029-035-041-082130-
/O.NEW.KPHI.SV.W.0216.120908T2030Z-120908T2130Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
430 PM EDT SAT SEP 8 2012

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  CAROLINE COUNTY IN EASTERN MARYLAND...
  TALBOT COUNTY IN EASTERN MARYLAND...
  KENT COUNTY IN NORTHEAST MARYLAND...
  QUEEN ANNE'S COUNTY IN NORTHEAST MARYLAND...

* UNTIL 530 PM EDT

* AT 427 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A 
  LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING WINDS   
  IN EXCESS OF 60 MPH.  THIS LINE WAS APPROACHING THE WESTERN SHORE  
  OF CHESAPEAKE BAY AND WAS MOVING EAST AT AROUND 40 MPH. 

* OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
  CHESAPEAKE BAY BRIDGE...ROMANCOKE...TILGHMAN ISLAND...
  STEVENSVILLE...CHESTER...TALBOT...OVERTON...ST. MICHAELS...
  GRASONVILLE...NEWTOWN...COPPERVILLE...OXFORD...LANGFORD...OLD
  TOWN...BETTERTON...CHESTERTOWN...WYE MILLS...CENTREVILLE...
  EASTON...SKIPTON...HAMBLETON...TRAPPE...STARKEY CORNER...MORGNEC...
  KENNEDYVILLE...STARR...CARVILLE...CHURCH HILL...CORDOVA...HOPE...
  TANYARD...WINDYHILL...QUEEN ANNE...MATTHEWS...CRUMPTON...
  CHOPTANK...JUMPTOWN...GRIFFIN...PRESTON...RIDGELY...OAKLAND...
  HARMONY...SUDLERSVILLE...MILLINGTON...MASSEY...SASSAFRAS...
  DENTON...GREENSBORO...GOLDSBORO...AGNER...FEDERALSBURG AND
  SMITHVILLE

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THESE ARE DANGEROUS STORMS. 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.

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 3872 7631 3866 7634 3877 7640 3887 7625
      3881 7621 3882 7620 3894 7624 3884 7638
      3886 7638 3904 7632 3899 7627 3900 7618
      3914 7629 3932 7619 3938 7612 3938 7577
      3864 7570 3869 7590 3857 7604
TIME...MOT...LOC 2028Z 272DEG 41KT 3911 7636

$$

JJM
1 follow-up statement
865 
WWUS51 KPHI 082058
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
458 PM EDT SAT SEP 8 2012

MDC011-029-035-041-082130-
/O.CON.KPHI.SV.W.0216.000000T0000Z-120908T2130Z/
KENT MD-CAROLINE MD-QUEEN ANNE'S MD-TALBOT MD-
458 PM EDT SAT SEP 8 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 530 PM EDT
FOR TALBOT...QUEEN ANNE'S...CAROLINE AND KENT COUNTIES...

AT 456 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO 
INDICATE SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING WINDS IN 
EXCESS OF 60 MPH.  ONE OF THE MOST DANGEROUS STORMS WAS LOCATED NEAR 
CENTREVILLE...OR 30 MILES WEST OF DOVER...MOVING EAST AT 45 MPH.

OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO STARKEY
CORNER...SKIPTON...EASTON...CARVILLE...CHURCH HILL...STARR...
HAMBLETON...TRAPPE...HOPE...CRUMPTON...CORDOVA...GALENA...QUEEN
ANNE...HILLSBORO...TANYARD...MATTHEWS...JUMPTOWN...WINDYHILL...
SUDLERSVILLE...BARCLAY...MASSEY...MILLINGTON...SASSAFRAS...GRIFFIN...
CHOPTANK...OAKLAND...RIDGELY...PRESTON...HARMONY...GREENSBORO...
TEMPLEVILLE...DENTON...GOLDSBORO...HENDERSON...MARYDEL...AGNER...
FEDERALSBURG AND SMITHVILLE

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THESE ARE DANGEROUS STORMS. IF YOU ARE IN THEIR 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.

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 3872 7631 3866 7634 3877 7640 3887 7625
      3881 7621 3882 7620 3894 7624 3884 7638
      3886 7638 3904 7632 3899 7627 3900 7618
      3914 7629 3932 7619 3938 7612 3938 7577
      3864 7570 3869 7590 3857 7604
TIME...MOT...LOC 2057Z 280DEG 39KT 3907 7605

$$

JJM

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 8, 4:07 PM EDTSpecial Weather StatementPHICaroline, Cecil, Kent, Queen Anne's, Talbot83 min

Nearby

Severe Thunderstorm Warnings in Maryland, 2012Every severe thunderstorm warning in 2012

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.