Alert archive / Pennsylvania / Special Weather Statements in 2011

Special Weather Statement, NWS Philadelphia/Mount Holly

July 25, 2011Delaware County, Pennsylvania

NWS Philadelphia/Mount Holly issued this special weather statement at Jul 25, 2011, 7:13 PM EDT for Delaware County, Pennsylvania. It was in force for 62 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: Jul 25, 2011, 7:13 PM EDT (23:13 UTC)
Expired: Jul 25, 2011, 8:15 PM EDT
In force: 62 min
Issued by: NWS Philadelphia/Mount Holly

County Delaware County, PA

The radar

The Philadelphia radar (KDIX), 92 km from the middle of the area, began a volume at 23:16 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, 11.2 hours before the alert went out and 72 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: 481 J/kg
Mixed-layer CIN: -66 J/kg
Mixed-layer LCL: 760 m above ground
0-6 km bulk shear: 18 kt
0-1 km storm-relative helicity: -6 m²/s²
0-3 km storm-relative helicity: 24 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

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

242 
WWUS81 KPHI 252313
SPSPHI

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
713 PM EDT MON JUL 25 2011

DEZ001-PAZ067-070-260015-
CHESTER PA-DELAWARE PA-NEW CASTLE DE-
713 PM EDT MON JUL 25 2011

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

AT 710 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 5 MILES EAST OF WEST CHESTER...MOVING SOUTHEAST 
AT 15 MPH. 

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

DANGEROUS CLOUD TO GROUND LIGHTNING IS OCCURRING WITH THIS STORM. DO 
NOT SEEK SHELTER UNDER TREES WHEN LIGHTNING THREATENS...MOVE INDOORS 
WHEN A THUNDERSTORM APPROACHES.

LAT...LON 3994 7527 3975 7548 3978 7586 4014 7556

$$

FORECASTER: GORSE

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 25, 7:47 AM EDT	Special Weather Statement	PHI	Sussex	58 min
Jul 25, 9:17 AM EDT	Special Weather Statement	PHI	Sussex	58 min
Jul 25, 10:19 AM EDT	Special Weather Statement	PHI	Sussex	56 min
Jul 25, 4:31 PM EDT	Areal Flood Advisory	PHI	Hunterdon, Warren	3 hr
Jul 25, 5:18 PM EDT	Flash Flood Warning	PHI	Warren	3 hr
Jul 24, 10:53 PM EDT	Special Weather Statement	PHI	Schuylkill	67 min
Jul 25, 6:19 AM EDT	Special Weather Statement	PHI	Monroe	56 min
Jul 25, 10:30 AM EDT	Special Weather Statement	PHI	Monroe	90 min
Jul 25, 11:51 AM EDT	Special Weather Statement	PHI	Berks	54 min
Jul 25, 11:58 AM EDT	Special Weather Statement	PHI	Carbon, Monroe	62 min
Jul 25, 12:19 PM EDT	Severe Thunderstorm Warning	PHI	Carbon, Monroe	56 min
Jul 25, 12:45 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Lehigh	60 min
Jul 25, 12:59 PM EDT	Areal Flood Advisory	PHI	Carbon	2 hr
Jul 25, 1:34 PM EDT	Special Weather Statement	PHI	Berks	56 min
Jul 25, 3:01 PM EDT	Special Weather Statement	PHI	Northampton	59 min
Jul 25, 4:25 PM EDT	Flash Flood Warning	PHI	Northampton	3 hr
Jul 25, 5:18 PM EDT	Special Weather Statement	PHI	Carbon, Monroe	57 min
Jul 25, 5:49 PM EDT	Areal Flood Advisory	PHI	Carbon, Monroe	93 min
Jul 25, 5:57 PM EDT	Special Weather Statement	PHI	Berks	63 min
Jul 25, 6:23 PM EDT	Areal Flood Advisory	PHI	Bucks, Chester, Delaware, Montgomery, Philadelphia	3 hr
Jul 25, 3:54 PM EDT	Special Weather Statement	PHI	Caroline, Kent, Queen Anne's, Talbot	66 min
Jul 25, 4:26 PM EDT	Special Weather Statement	PHI	Caroline, Kent, Queen Anne's, Talbot	94 min
Jul 25, 4:49 PM EDT	Areal Flood Advisory	PHI	Kent, Queen Anne's	100 min
Jul 25, 5:02 PM EDT	Areal Flood Advisory	PHI	Caroline	2 hr
Jul 25, 2:10 AM EDT	Special Weather Statement	PHI	Sussex	2 hr
Jul 25, 4:15 PM EDT	Special Weather Statement	PHI	Kent	60 min
Jul 25, 5:04 PM EDT	Special Weather Statement	PHI	Sussex	56 min
Jul 25, 6:10 PM EDT	Areal Flood Advisory	PHI	Sussex	77 min

Nearby

Special Weather Statements in Pennsylvania, 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.