Alert archive / Pennsylvania / Special Weather Statements in 2012

Special Weather Statement, NWS Philadelphia/Mount Holly

August 14, 2012Delaware County, Pennsylvania

NWS Philadelphia/Mount Holly issued this special weather statement at Aug 14, 2012, 4:12 PM EDT for Delaware County, Pennsylvania. It was in force for 63 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 14, 2012, 4:12 PM EDT (20:12 UTC)
Expired: Aug 14, 2012, 5:15 PM EDT
In force: 63 min
Issued by: NWS Philadelphia/Mount Holly

County Delaware County, PA

The radar

The Philadelphia radar (KDIX), 93 km from the middle of the area, began a volume at 20:12 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, 8.2 hours before the alert went out and 69 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: 1166 J/kg
Mixed-layer CIN: -17 J/kg
Mixed-layer LCL: 696 m above ground
0-6 km bulk shear: 38 kt
0-1 km storm-relative helicity: 258 m²/s²
0-3 km storm-relative helicity: 256 m²/s²
Significant tornado parameter: 1.2
Supercell composite: 7.9

Open this sounding in Storm Lab

The text

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

858 
WWUS81 KPHI 142012
SPSPHI

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
412 PM EDT TUE AUG 14 2012

DEZ001-PAZ067-070-142115-
CHESTER PA-DELAWARE PA-NEW CASTLE DE-
412 PM EDT TUE AUG 14 2012

...A STRONG THUNDERSTORM WILL AFFECT CHESTER...DELAWARE AND NEW
CASTLE COUNTIES...

AT 408 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 6 MILES NORTH OF WILMINGTON...MOVING NORTH AT 20
MPH. THE THUNDERSTORM WILL BE NEAR WESTTOWN...CONCORDVILLE AROUND 430
PM...WEST GOSHEN...WEST CHESTER AROUND 445 PM...EXTON AND MALVERN
AROUND 500 PM.

VERY HEAVY RAIN WILL FALL FROM THIS STORM...AND WILL CAUSE WATER TO
POND ON ROADS AND QUICKLY FILL POOR DRAINAGE AREAS.

WIND GUSTS TO 40 MPH ARE POSSIBLE WITH THIS STORM.

EXPECT SMALL HAIL AND FREQUENT...DANGEROUS CLOUD TO GROUND LIGHTNING.

LAT...LON 4008 7541 3979 7541 3976 7546 3974 7547
      3973 7564 4006 7573

$$

KRUZDLO

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 14, 9:22 AM EDT	Severe Thunderstorm Warning	PHI	Camden, Gloucester, Salem	38 min
Aug 14, 9:44 AM EDT	Special Weather Statement	PHI	Hunterdon, Mercer	91 min
Aug 14, 10:07 AM EDT	Special Weather Statement	PHI	Camden, Gloucester, Salem	83 min
Aug 14, 11:42 AM EDT	Areal Flood Advisory	PHI	Atlantic, Burlington, Camden, Gloucester	3 hr
Aug 14, 2:35 PM EDT	Areal Flood Advisory	PHI	Atlantic, Burlington, Ocean	78 min
Aug 14, 3:46 PM EDT	Flash Flood Warning	PHI	Atlantic, Burlington, Ocean	2 hr
Aug 14, 6:02 AM EDT	Special Weather Statement	PHI	Carbon	88 min
Aug 14, 7:25 AM EDT	Special Weather Statement	PHI	Berks, Carbon, Lehigh	95 min
Aug 14, 8:06 AM EDT	Special Weather Statement	PHI	Chester, Lehigh	84 min
Aug 14, 8:39 AM EDT	Areal Flood Advisory	PHI	Berks, Bucks, Chester, Lehigh, Montgomery	2 hr
Aug 14, 9:56 AM EDT	Areal Flood Advisory	PHI	Bucks, Chester, Delaware, Montgomery, Philadelphia	108 min
Aug 14, 4:15 PM EDT	Special Weather Statement	PHI	Delaware, Philadelphia	60 min
Aug 14, 12:49 PM EDT	Special Weather Statement	PHI	Sussex	56 min
Aug 14, 2:13 PM EDT	Areal Flood Advisory	PHI	Kent	79 min
Aug 14, 2:28 PM EDT	Areal Flood Advisory	PHI	Kent, New Castle	2 hr
Aug 14, 3:01 PM EDT	Severe Thunderstorm Warning	PHI	Kent, New Castle	38 min
Aug 14, 3:22 PM EDT	Special Weather Statement	PHI	New Castle	53 min
Aug 14, 4:54 PM EDT	Special Weather Statement	PHI	Kent	66 min
Aug 14, 6:44 PM EDT	Special Weather Statement	PHI	Sussex	61 min
Aug 14, 7:42 AM EDT	Special Weather Statement	PHI	Kent	63 min
Aug 14, 2:02 PM EDT	Special Weather Statement	PHI	Queen Anne's	58 min

Nearby

Special Weather Statements in Pennsylvania, 2012 Every 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.