Alert archive / Pennsylvania / Special Weather Statements in 2012
Special Weather Statement, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this special weather statement at Aug 11, 2012, 8:16 PM EDT for Chester County, Pennsylvania. It was in force for 29 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 11, 2012, 8:16 PM EDT (00:16 UTC)
- Expired
- Aug 11, 2012, 8:45 PM EDT
- In force
- 29 min
- Issued by
- NWS Philadelphia/Mount Holly
County Chester County, PA
The radar
The Philadelphia radar (KDIX), 124 km from the middle of the area, began a volume at 00:16 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
Washington/Dulle, VA (KIAD), launched 00:00Z, 0.3 hours before the alert went out and 169 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.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 0 m above ground
- 0-6 km bulk shear
- 41 kt
- 0-1 km storm-relative helicity
- 30 m²/s²
- 0-3 km storm-relative helicity
- 73 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.2
The text
As transmitted, in the capitals the NWS used until 2016.
709
WWUS81 KPHI 120016
SPSPHI
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
816 PM EDT SAT AUG 11 2012
PAZ067-068-120045-
CHESTER PA-MONTGOMERY PA-
816 PM EDT SAT AUG 11 2012
...STRONG THUNDERSTORMS WILL AFFECT CHESTER AND MONTGOMERY COUNTIES
IN SOUTHEAST PENNSYLVANIA...
AT 811 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM 9 MILES NORTH OF
WEST CHESTER TO 6 MILES WEST OF WEST CHESTER TO 8 MILES NORTHWEST OF
NEWARK...MOVING NORTHEAST AT 25 MPH. THE THUNDERSTORMS WILL BE NEAR
PUGHTOWN...LADENBERG...LIONVILLE AROUND 820 PM...CHESTER SPRINGS
AROUND 825 PM...TOUGHKENAMON...AVONDALE AROUND 830 PM...SANATOGA...
KENNETT SQUARE AROUND 835 PM...SPRING CITY AND ROYERSFORD AROUND 840
PM.
ANOTHER GROUP OF HEAVY SHOWERS AND ISOLATED EMBEDDED THUNDERSTORMS
WAS HEADING NORTHEAST FROM LANCASTER COUNTY INTO WESTERN CHESTER
COUNTY.
VERY HEAVY RAIN WILL FALL FROM THESE STORMS...AND WILL CAUSE WATER TO
POND ON ROADS AND QUICKLY FILL POOR DRAINAGE AREAS.
FREQUENT CLOUD TO GROUND LIGHTNING IS OCCURRING WITH THESE STORMS. DO
NOT SEEK SHELTER UNDER TREES WHEN LIGHTNING THREATENS...MOVE INDOORS
WHEN A THUNDERSTORM APPROACHES.
A WIND GUST TO 35 MPH IS POSSIBLE WITH SEVERAL OF THESE STORMS.
LAT...LON 3974 7610 3983 7602 3985 7603 3988 7600
3991 7601 4015 7576 4036 7544 4018 7538
3995 7555 3981 7569 3977 7574 3973 7577
3972 7613 3972 7614
$$
FORECASTER: DRAGThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 11, 8:26 PM EDT | Special Weather Statement | PHI | Mercer | 34 min |
| Aug 11, 8:39 PM EDT | Areal Flood Advisory | PHI | Hunterdon, Mercer, Somerset | 57 min |
| Aug 11, 8:10 PM EDT | Special Weather Statement | PHI | Bucks | 35 min |
| Aug 11, 9:04 PM EDT | Special Weather Statement | PHI | Bucks | 26 min |
Nearby
Special Weather Statements in Pennsylvania, 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.