Alert archive / Pennsylvania / Special Weather Statements in 2011
Special Weather Statement, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this special weather statement at Jul 11, 2011, 9:49 PM EDT for Chester County, Delaware County, Philadelphia County, Pennsylvania. It was in force for 56 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 11, 2011, 9:49 PM EDT (01:49 UTC)
- Expired
- Jul 11, 2011, 10:45 PM EDT
- In force
- 56 min
- Issued by
- NWS Philadelphia/Mount Holly
Counties Chester County, PA, Delaware County, PA, Philadelphia County, PA
The radar
The Philadelphia radar (KDIX), 86 km from the middle of the area, began a volume at 01:52 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, 1.8 hours before the alert went out and 205 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
- 3066 J/kg
- Mixed-layer CIN
- -11 J/kg
- Mixed-layer LCL
- 1246 m above ground
- 0-6 km bulk shear
- 20 kt
- 0-1 km storm-relative helicity
- 75 m²/s²
- 0-3 km storm-relative helicity
- 166 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 8.0
The text
As transmitted, in the capitals the NWS used until 2016.
903
WWUS81 KPHI 120149
SPSPHI
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
949 PM EDT MON JUL 11 2011
DEZ001-NJZ016>018-PAZ067-070-071-120245-
CAMDEN NJ-CHESTER PA-DELAWARE PA-GLOUCESTER NJ-NEW CASTLE DE-
PHILADELPHIA PA-SALEM NJ-
949 PM EDT MON JUL 11 2011
...STRONG THUNDERSTORMS WILL AFFECTING CHESTER AND APPROACHING
CAMDEN...DELAWARE...GLOUCESTER...NEW CASTLE...PHILADELPHIA AND SALEM
COUNTIES...
AT 944 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED AN
AREA OF STRONG THUNDERSTORMS FROM ABOUT 10 MILES WEST OF WEST
CHESTER TO THE MASON-DIXON LINE...MOVING EAST AT 35 MPH. THE
THUNDERSTORMS WILL BE NEAR DOWNINGTOWN...NORTH STAR...HOCKESSIN AND
MARSHALLTON AROUND 955 PM...EXTON...LIONVILLE AND ASHLAND AROUND
1000 PM...AND WEST GOSHEN...WEST CHESTER AND ELSMERE AROUND 1005 PM.
WIND GUSTS TO 40 MPH AND SMALL HAIL ARE POSSIBLE WITH THESE STORMS.
EXPECT DANGEROUS CLOUD TO GROUND LIGHTNING FROM THESE STORMS. DO NOT
SEEK SHELTER UNDER TREES WHEN LIGHTNING THREATENS...MOVE INDOORS
WHEN A THUNDERSTORM APPROACHES.
LAT...LON 4009 7586 4006 7536 4001 7534 4002 7532
3998 7528 4001 7522 4005 7527 4004 7511
3974 7514 3973 7586
$$
MPDThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 11, 9:11 PM EDT | Severe Thunderstorm Warning | PHI | Cecil, Kent, Queen Anne's | 64 min |
| Jul 11, 9:25 PM EDT | Special Weather Statement | PHI | Queen Anne's, Talbot | 65 min |
| Jul 11, 9:33 PM EDT | Severe Thunderstorm Warning | PHI | Caroline, Kent, Queen Anne's, Talbot | 57 min |
| Jul 11, 10:28 PM EDT | Severe Thunderstorm Warning | PHI | Caroline, Talbot | 33 min |
Nearby
Special Weather Statements in Pennsylvania, 2011Every 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.