Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2011
Severe Thunderstorm Warning 208, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 29, 2011, 6:43 PM EDT for Philadelphia County, Pennsylvania. It was in force for 49 min. 1 report came from inside the area while it was in force.
The area
The outline as issued, with what was reported inside it.
The facts
- Issued
- Jul 29, 2011, 6:43 PM EDT (22:43 UTC)
- Expired
- Jul 29, 2011, 7:32 PM EDT
- In force
- 49 min
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
County Philadelphia County, PA
The radar
The Philadelphia radar (KDIX), 63 km from the middle of the area, began a volume at 22:43 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.
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Jul 29, 7:05 PM EDT | TSTM WND DMG | 2 Ne Philadelphia, PA | TREES DOWN... WHICH TOOK DOWN POWER LINES IN THE BURHOLME SECTION OF THE CITY. A CAR CAUGHT FIRE DUE TO FALLEN POWER LINES. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The watch it was issued in
The SPC watch in force over the same counties when this warning went out.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| Jul 29, 2:40 PM EDT | Severe Thunderstorm Watch | SPC | 8 hr |
The nearest sounding before it
Brookhaven, NY (KOKX), launched 12:00Z, 10.7 hours before the alert went out and 215 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
- 81 J/kg
- Mixed-layer CIN
- -109 J/kg
- Mixed-layer LCL
- 569 m above ground
- 0-6 km bulk shear
- 26 kt
- 0-1 km storm-relative helicity
- 8 m²/s²
- 0-3 km storm-relative helicity
- 19 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -0.0
The text
As transmitted, in the capitals the NWS used until 2016.
138
WUUS51 KPHI 292243
SVRPHI
PAC101-292345-
/O.NEW.KPHI.SV.W.0208.110729T2243Z-110729T2345Z/
BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
643 PM EDT FRI JUL 29 2011
THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A
* SEVERE THUNDERSTORM WARNING FOR...
PHILADELPHIA COUNTY IN SOUTHEAST PENNSYLVANIA...
THIS INCLUDES THE CITY OF PHILADELPHIA...
* UNTIL 745 PM EDT
* AT 641 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL...AND
DAMAGING WINDS IN EXCESS OF 70 MPH. THIS STORM WAS LOCATED 7 MILES
NORTH OF CHESTNUT HILL...OR 12 MILES NORTH OF PHILADELPHIA...AND
MOVING SOUTHEAST AT 30 MPH.
* OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
MORRIS PARK...GERMANTOWN...ROXBOROUGH...PHILADELPHIA INTERNATIONAL
AIRPORT...SOUTH PHILADELPHIA...CENTER CITY...KENSINGTON...NORTHEAST
PHILADELPHIA...WISSINOMING...TACONY AND HOLMESBURG
PRECAUTIONARY/PREPAREDNESS ACTIONS...
THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...PREPARE
IMMEDIATELY FOR DAMAGING WINDS...DESTRUCTIVE HAIL...AND DEADLY CLOUD
TO GROUND LIGHTNING. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...
PREFERABLY INSIDE A STRONG BUILDING BUT AWAY FROM WINDOWS.
PLEASE REPORT HAIL OR STRONG WINDS TO THE NATIONAL WEATHER SERVICE BY
CALLING TOLL FREE...1-877-633-6772...WHEN YOU CAN DO SO SAFELY.
A TORNADO WATCH REMAINS IN EFFECT UNTIL 1100 PM EDT FRIDAY EVENING
FOR NORTHWEST NEW JERSEY AND NORTHEAST PENNSYLVANIA. A SEVERE
THUNDERSTORM WATCH ALSO REMAINS IN EFFECT UNTIL 1100 PM EDT FRIDAY
EVENING FOR NEW JERSEY AND EASTERN PENNSYLVANIA.
&&
LAT...LON 4003 7499 3995 7514 3989 7514 3988 7515
3985 7524 3988 7527 3994 7525 3998 7528
4002 7522 4006 7527 4009 7522 4005 7512
4013 7504 4013 7499 4011 7497
TIME...MOT...LOC 2243Z 307DEG 28KT 4016 7520
$$
JJM1 follow-up statement
943
WWUS51 KPHI 292332
SVSPHI
SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
732 PM EDT FRI JUL 29 2011
PAC101-292341-
/O.CAN.KPHI.SV.W.0208.000000T0000Z-110729T2345Z/
PHILADELPHIA PA-
732 PM EDT FRI JUL 29 2011
...THE SEVERE THUNDERSTORM WARNING FOR PHILADELPHIA COUNTY IS
CANCELLED...
THE THREAT OF SEVERE WEATHER HAS ENDED FROM THIS STORM FOR THE CITY
OF PHILADELPHIA.
A TORNADO WATCH REMAINS IN EFFECT UNTIL 1100 PM EDT FRIDAY EVENING
FOR NORTHWEST NEW JERSEY AND NORTHEAST PENNSYLVANIA. A SEVERE
THUNDERSTORM WATCH ALSO REMAINS IN EFFECT UNTIL 1100 PM EDT FRIDAY
EVENING FOR NEW JERSEY AND EASTERN PENNSYLVANIA.
LAT...LON 4003 7499 3995 7514 3989 7514 3988 7515
3985 7524 3988 7527 3994 7525 3998 7528
4002 7522 4006 7527 4009 7522 4005 7512
4013 7504 4013 7499 4011 7497
TIME...MOT...LOC 2331Z 307DEG 28KT 3993 7481
$$
SZATKOWSKIThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 29, 3:44 PM EDT | Special Weather Statement | PHI | Berks, Carbon, Lehigh, Monroe, Northampton | 2 hr |
| Jul 29, 4:40 PM EDT | Severe Thunderstorm Warning | PHI | Berks, Lehigh | 65 min |
| Jul 29, 5:56 PM EDT | Special Weather Statement | PHI | Bucks | 64 min |
| Jul 29, 6:05 PM EDT | Severe Thunderstorm Warning | PHI | Bucks, Montgomery | 55 min |
| Jul 29, 7:03 PM EDT | Severe Thunderstorm Warning | PHI | Bucks | 46 min |
| Jul 29, 7:13 PM EDT | Special Weather Statement | PHI | Montgomery | 62 min |
| Jul 29, 7:31 PM EDT | Special Weather Statement | PHI | Bucks, Montgomery, Philadelphia | 59 min |
Nearby
Severe Thunderstorm Warnings in Pennsylvania, 2011Every severe thunderstorm warning 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.