Alert archive / Pennsylvania / Special Weather Statements in 2015

Special Weather Statement, NWS Philadelphia/Mount Holly

August 4, 2015Chester County, Pennsylvania

NWS Philadelphia/Mount Holly issued this special weather statement at Aug 4, 2015, 12:06 AM EDT for Chester County, Pennsylvania. It was in force for 54 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 4, 2015, 12:06 AM EDT (04:06 UTC)
Expired: Aug 4, 2015, 1:00 AM EDT
In force: 54 min
Issued by: NWS Philadelphia/Mount Holly

County Chester County, PA

The radar

The Philadelphia radar (KDIX), 119 km from the middle of the area, began a volume at 04:06 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

Washington/Dulle, VA (KIAD), launched 00:00Z, 4.1 hours before the alert went out and 194 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: 627 J/kg
Mixed-layer CIN: -33 J/kg
Mixed-layer LCL: 1863 m above ground
0-6 km bulk shear: 38 kt
0-1 km storm-relative helicity: 90 m²/s²
0-3 km storm-relative helicity: 156 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.9

Open this sounding in Storm Lab

The text

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

572 
WWUS81 KPHI 040406
SPSPHI

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1206 AM EDT TUE AUG 4 2015
 
PAZ060-101>104-040500-
BERKS-WESTERN CHESTER-WESTERN MONTGOMERY-EASTERN MONTGOMERY-EASTERN
CHESTER-
1206 AM EDT TUE AUG 4 2015

...A STRONG THUNDERSTORM WILL AFFECT NORTHERN CHESTER...SOUTHEASTERN
BERKS AND NORTHWESTERN MONTGOMERY COUNTIES...

AT 1205 AM EDT...A STRONG THUNDERSTORM WAS OVER TERRE HILL...OR NEAR
NEW HOLLAND...MOVING EAST AT 35 MPH.

WIND GUSTS UP TO 40 MPH ARE POSSIBLE WITH THIS STORM.

LOCATIONS IMPACTED INCLUDE...
READING...POTTSTOWN...PHOENIXVILLE...COATESVILLE...WYOMISSING...
DOWNINGTOWN...BIRDSBORO...COLLEGEVILLE...ROYERSFORD...SINKING
SPRING...PARKESBURG...TRAPPE...EAST GREENVILLE...WERNERSVILLE...
ADAMSTOWN...HONEY BROOK...SCHWENKSVILLE...ELVERSON...BALLY AND
BECHTELSVILLE.

VERY HEAVY RAINFALL IS ALSO OCCURRING WITH THIS STORM...AND MAY 
CAUSE LOCALIZED FLOODING. DO NOT DRIVE YOUR VEHICLE THROUGH FLOODED 
ROADWAYS.

FREQUENT CLOUD TO GROUND LIGHTNING IS OCCURRING WITH THIS STORM.
LIGHTNING CAN STRIKE 15 MILES AWAY FROM A THUNDERSTORM. SEEK A SAFE
SHELTER INSIDE A BUILDING OR VEHICLE.

THIS STORM MAY INTENSIFY...SO BE CERTAIN TO MONITOR LOCAL RADIO AND
TV STATIONS...AS WELL AS LOCAL CABLE TV OUTLETS...FOR ADDITIONAL
INFORMATION AND POSSIBLE WARNINGS FROM THE NATIONAL WEATHER SERVICE.

LAT...LON 4043 7552 4027 7539 4000 7546 3994 7599
      3995 7600 4004 7593 4011 7594 4014 7588
      4031 7615
TIME...MOT...LOC 0405Z 260DEG 30KT 4015 7607 
$$

HEAVENER

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 4, 2:07 AM EDT	Special Weather Statement	PHI	Hunterdon, Mercer, Middlesex, Somerset	53 min
Aug 4, 2:30 AM EDT	Special Weather Statement	PHI	Morris, Warren	60 min
Aug 4, 2:56 AM EDT	Special Weather Statement	PHI	Hunterdon, Mercer, Middlesex, Monmouth, Somerset	64 min
Aug 4, 3:33 AM EDT	Special Marine Warning	PHI		57 min
Aug 4, 3:36 AM EDT	Special Weather Statement	PHI	Morris	24 min
Aug 4, 4:12 AM EDT	Special Weather Statement	PHI	Gloucester	63 min
Aug 4, 4:20 AM EDT	Severe Thunderstorm Warning	PHI	Gloucester, Salem	33 min
Aug 4, 5:25 AM EDT	Special Weather Statement	PHI	Monmouth	65 min
Aug 4, 10:53 AM EDT	Rip Current Statement	PHI	Cape May	4 hr
Aug 4, 12:45 AM EDT	Special Weather Statement	PHI	Bucks, Chester, Montgomery, Philadelphia	60 min
Aug 4, 1:23 AM EDT	Special Weather Statement	PHI	Berks	37 min
Aug 4, 1:31 AM EDT	Severe Thunderstorm Warning	PHI	Berks	44 min
Aug 4, 1:42 AM EDT	Special Weather Statement	PHI	Carbon	48 min
Aug 4, 1:54 AM EDT	Severe Thunderstorm Warning	PHI	Berks, Carbon, Lehigh, Monroe, Northampton	50 min
Aug 4, 5:18 AM EDT	Special Weather Statement	PHI	Kent, Queen Anne's	57 min
Aug 4, 5:37 AM EDT	Severe Thunderstorm Warning	PHI	Cecil, Kent, Queen Anne's	34 min
Aug 4, 6:11 PM EDT	Special Weather Statement	PHI	Sussex	64 min
Aug 4, 6:20 PM EDT	Severe Thunderstorm Warning	PHI	Sussex	20 min

Nearby

Special Weather Statements in Pennsylvania, 2015 Every special weather statement in 2015

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.