Alert archive / Maryland / Special Weather Statements in 2012

Special Weather Statement, NWS Philadelphia/Mount Holly

July 9, 20124 counties in New Jersey; Kent County, New Castle County, Sussex County, Delaware; 5 counties in Maryland

NWS Philadelphia/Mount Holly issued this special weather statement at Jul 9, 2012, 5:20 AM EDT for 4 counties in New Jersey; Kent County, New Castle County, Sussex County, Delaware; 5 counties in Maryland. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jul 9, 2012, 5:20 AM EDT (09:20 UTC)
Expired
Jul 9, 2012, 8:00 AM EDT
In force
3 hr
Issued by
NWS Philadelphia/Mount Holly

Counties Kent County, DE, New Castle County, DE, Sussex County, DE, Caroline County, MD, Cecil County, MD, Kent County, MD, Queen Anne's County, MD, Talbot County, MD, Atlantic County, NJ, Cape May County, NJ, Cumberland County, NJ, Salem County, NJ

The radar

The Dover AFB radar (KDOX), 29 km from the middle of the area, began a volume at 09:21 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.

The nearest sounding before it

Wallops Is Stn, VA (KWAL), launched 00:00Z, 9.3 hours before the alert went out and 127 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, Wallops Is Stn, VA at 00:00Z on 2012-07-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 4020 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, Wallops Is Stn, VA at 00:00Z on 2012-07-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 114 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
4020 J/kg
Mixed-layer CIN
-71 J/kg
Mixed-layer LCL
1020 m above ground
0-6 km bulk shear
31 kt
0-1 km storm-relative helicity
114 m²/s²
0-3 km storm-relative helicity
125 m²/s²
Significant tornado parameter
1.7
Supercell composite
10.8

Open this sounding in Storm Lab

The text

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

209 
WWUS81 KPHI 090920
SPSPHI

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
520 AM EDT MON JUL 9 2012

DEZ001>004-MDZ008-012-015-019-020-NJZ016>018-021>025-091200-
ATLANTIC NJ-ATLANTIC COASTAL CAPE MAY NJ-CAMDEN NJ-CAPE MAY NJ-
CAROLINE MD-CECIL MD-COASTAL ATLANTIC NJ-CUMBERLAND NJ-
DELAWARE BEACHES DE-GLOUCESTER NJ-INLAND SUSSEX DE-KENT DE-KENT MD-
NEW CASTLE DE-QUEEN ANNE'S MD-SALEM NJ-TALBOT MD-
520 AM EDT MON JUL 9 2012

...SHOWERS AND THUNDERSTORMS WILL MOVE ACROSS DELAWARE...THE 
NORTHERN MARYLAND EASTERN SHORE AND SOUTHERN NEW JERSEY WELL THROUGH 
DAYBREAK...

AT 512 AM EDT, NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED 
SHOWERS AND THUNDERSTORMS FROM THE EASTERN PANHANDLE OF WEST 
VIRGINIA AND NORTHERN VIRGINIA ACROSS ALL OF MARYLAND AND DELAWARE 
TO FAR SOUTHERN NEW JERSEY. THE ACTIVITY WAS MOVING EAST AT AROUND 
25 MPH, AND IT IS EXPECTED TO MOVE ACROSS DELAWARE, THE NORTHERN 
MARYLAND EASTERN SHORE AND SOUTHERN NEW JERSEY THROUGH 800 AM EDT.

THE STRONGEST STORMS WILL GENERATE DANGEROUS CLOUD TO GROUND 
LIGHTNING AND HEAVY DOWNPOURS THAT WILL RESULT IN SOME PONDING OF 
WATER AND POOR DRAINAGE FLOODING. IF YOU HEAR THUNDER, PLEASE MOVE 
INDOORS. IF YOU ARE DRIVING THIS MORNING AND ENCOUNTER A FLOODED 
ROAD, PLEASE DO NOT TRY TO DRIVE THROUGH THE WATER. FIND AN 
ALTERNATE ROUTE. 

LAT...LON 3845 7569 3870 7584 3857 7603 3867 7635
      3883 7626 3881 7621 3882 7620 3884 7638
      3917 7629 3952 7599 3972 7622 3972 7473
      3950 7430 3948 7429 3893 7497 3916 7490
      3949 7557 3948 7558 3880 7508 3844 7505

$$

MPD

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 8, 9:01 PM EDTSpecial Marine WarningPHI59 min
Jul 8, 8:30 PM EDTSpecial Weather StatementPHISussex60 min
Jul 8, 8:52 PM EDTSevere Thunderstorm WarningPHISussex53 min
Jul 8, 10:15 PM EDTSevere Thunderstorm WarningPHIKent25 min
Jul 8, 9:09 PM EDTSpecial Weather StatementPHICaroline, Kent, Queen Anne's66 min
Jul 8, 9:22 PM EDTSevere Thunderstorm WarningPHICaroline, Queen Anne's, Talbot53 min
Jul 8, 10:13 PM EDTSpecial Weather StatementPHICaroline, Queen Anne's62 min

Nearby

Special Weather Statements in Maryland, 2012Special Weather Statements in New Jersey, 2012Special Weather Statements in Delaware, 2012Every special weather statement 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.