Alert archive / Pennsylvania / Special Weather Statements in 2011

Special Weather Statement, NWS Philadelphia/Mount Holly

August 9, 2011Gloucester County, New Jersey; 4 counties in Pennsylvania; Cecil County, Maryland

NWS Philadelphia/Mount Holly issued this special weather statement at Aug 9, 2011, 5:48 PM EDT for Gloucester County, New Jersey; 4 counties in Pennsylvania; Cecil County, Maryland. It was in force for 87 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 9, 2011, 5:48 PM EDT (21:48 UTC)
Expired: Aug 9, 2011, 7:15 PM EDT
In force: 87 min
Issued by: NWS Philadelphia/Mount Holly

Counties Cecil County, MD, Gloucester County, NJ, Chester County, PA, Delaware County, PA, Montgomery County, PA, Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 104 km from the middle of the area, began a volume at 21:48 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

Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 9.8 hours before the alert went out and 61 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 210 J/kg
Mixed-layer CIN: -77 J/kg
Mixed-layer LCL: 1178 m above ground
0-6 km bulk shear: 37 kt
0-1 km storm-relative helicity: 96 m²/s²
0-3 km storm-relative helicity: 173 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.5

Open this sounding in Storm Lab

The text

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

773 
WWUS81 KPHI 092148
SPSPHI

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
548 PM EDT TUE AUG 9 2011

DEZ001-MDZ008-NJZ016>019-PAZ067>071-092315-
BUCKS PA-CAMDEN NJ-CECIL MD-CHESTER PA-DELAWARE PA-GLOUCESTER NJ-
MONTGOMERY PA-NEW CASTLE DE-NORTHWESTERN BURLINGTON NJ-
PHILADELPHIA PA-SALEM NJ-
548 PM EDT TUE AUG 9 2011

...STRONG THUNDERSTORM WILL AFFECT BUCKS...BURLINGTON...CAMDEN 
...CECIL...CHESTER...DELAWARE...GLOUCESTER ...MONTGOMERY...NEW 
CASTLE...PHILADELPHIA AND SALEM COUNTIES...

AT 539 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED AN 
AREA OF STRONG THUNDERSTORMS ACROSS CHESTER COUNTY PENNSYLVANIA 
MOVING SOUTHEAST AT 20 MPH.  THESE THUNDERSTORMS WILL AFFECT 
PORTIONS OF MONTGOMERY...PHILADELPHIA...DELAWARE AND BUCKS COUNTY IN 
PENNSYLVANIA AS WELL AS BURLINGTON...CAMDEN, GLOUCESTER AND SALEM 
COUNTIES IN NEW JERSEY.  ADDITIONALLY, NEW CASTLE COUNTY IN DELAWARE 
AND CECIL COUNTY IN MARYLAND WILL BE IMPACTED BY THESE STORMS.  

WIND GUSTS TO 50 MPH ARE POSSIBLE WITH THIS STORM.

LAT...LON 3973 7623 3973 7615 3978 7607 3987 7601
      4011 7595 4024 7570 4043 7554 4020 7478
      4015 7472 4017 7469 4015 7465 3970 7508
      3962 7558 3969 7552 3961 7560 3953 7601
      3954 7607 3970 7624

$$

NIERENBERG

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 9, 12:18 PM EDT	Severe Thunderstorm Warning	PHI	Gloucester	57 min
Aug 9, 12:32 PM EDT	Tornado Warning	PHI	Gloucester	28 min
Aug 9, 1:02 PM EDT	Special Weather Statement	PHI	Camden, Gloucester, Salem	58 min
Aug 9, 1:08 PM EDT	Severe Thunderstorm Warning	PHI	Atlantic, Camden, Cumberland, Gloucester, Salem	67 min
Aug 9, 1:17 PM EDT	Special Weather Statement	PHI	Burlington, Camden, Gloucester	58 min
Aug 9, 2:16 PM EDT	Special Weather Statement	PHI	Atlantic	59 min
Aug 9, 2:22 PM EDT	Areal Flood Advisory	PHI	Camden, Cumberland, Gloucester, Salem	3 hr
Aug 9, 2:22 PM EDT	Severe Thunderstorm Warning	PHI	Mercer, Middlesex, Monmouth	53 min
Aug 9, 2:53 PM EDT	Areal Flood Advisory	PHI	Middlesex, Morris, Somerset	3 hr
Aug 9, 3:27 PM EDT	Special Weather Statement	PHI	Atlantic	63 min
Aug 9, 4:13 PM EDT	Special Marine Warning	PHI		92 min
Aug 9, 6:54 PM EDT	Special Weather Statement	PHI	Atlantic, Camden, Cape May, Cumberland, Gloucester, Salem	81 min
Aug 9, 11:46 AM EDT	Special Weather Statement	PHI	Chester, Delaware, Montgomery	59 min
Aug 9, 12:40 PM EDT	Special Weather Statement	PHI	Cecil	65 min
Aug 9, 5:13 PM EDT	Special Weather Statement	PHI	Kent, Queen Anne's	62 min
Aug 9, 6:35 PM EDT	Special Weather Statement	PHI	Talbot	85 min

Nearby

Special Weather Statements in Pennsylvania, 2011 Special Weather Statements in New Jersey, 2011 Special Weather Statements in Maryland, 2011 Every special weather statement 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; radar from the NEXRAD Level II archive.