Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2011
Severe Thunderstorm Warning 152, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 7, 2011, 4:35 PM EDT for Chester County, Pennsylvania. It was in force for 55 min. 2 reports 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 7, 2011, 4:35 PM EDT (20:35 UTC)
- Expired
- Jul 7, 2011, 5:30 PM EDT
- In force
- 55 min
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
County Chester County, PA
The radar
The Philadelphia radar (KDIX), 108 km from the middle of the area, began a volume at 20:39 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 7, 4:40 PM EDT | TSTM WND DMG | Exton, PA | TREES REPORTED DOWN IN WEST WHITELAND TOWNSHIP. |
| Jul 7, 5:10 PM EDT | TSTM WND DMG | East Goshen Twp, PA | SEVERAL LARGE TREES DOWN |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The nearest sounding before it
Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 8.6 hours before the alert went out and 75 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
- 549 J/kg
- Mixed-layer CIN
- -133 J/kg
- Mixed-layer LCL
- 1227 m above ground
- 0-6 km bulk shear
- 16 kt
- 0-1 km storm-relative helicity
- -7 m²/s²
- 0-3 km storm-relative helicity
- 30 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
643
WUUS51 KPHI 072035
SVRPHI
PAC029-072130-
/O.NEW.KPHI.SV.W.0152.110707T2035Z-110707T2130Z/
BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
435 PM EDT THU JUL 7 2011
THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A
* SEVERE THUNDERSTORM WARNING FOR...
NORTHERN CHESTER COUNTY IN SOUTHEAST PENNSYLVANIA...
* UNTIL 530 PM EDT
* AT 434 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL...AND
DAMAGING WINDS IN EXCESS OF 60 MPH. THIS STORM WAS LOCATED 8 MILES
WEST OF HONEY BROOK...OR 13 MILES EAST OF LANCASTER...AND MOVING
EAST AT 15 MPH.
* THE SEVERE THUNDERSTORM WILL BE NEAR...
HONEY BROOK AROUND 455 PM EDT...
ELVERSON AROUND 510 PM EDT...
GLENMOORE AROUND 520 PM EDT...
CHESTER SPRINGS...LIONVILLE...PUGHTOWN AND 7 MILES NORTH OF
DOWNINGTOWN AROUND 530 PM EDT...
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.
IN ADDITION TO LARGE HAIL AND DAMAGING WINDS...CONTINUOUS CLOUD TO
GROUND LIGHTNING IS OCCURRING WITH THIS STORM. MOVE INDOORS
IMMEDIATELY! LIGHTNING IS ONE OF NATURES GREATEST KILLERS.
REMEMBER...IF YOU CAN HEAR THUNDER...YOU ARE CLOSE ENOUGH TO BE
STRUCK BY LIGHTNING.
IN ADDITION TO LARGE HAIL AND DAMAGING WINDS...HEAVY RAIN WILL OCCUR
WITH THESE STORMS AND CAUSE LOW-LYING AND POOR DRAINAGE FLOODING.
&&
LAT...LON 4003 7595 4011 7595 4018 7582 4019 7557
4012 7551 4007 7540 4000 7545 4000 7546
3999 7545 3997 7551 4000 7597
TIME...MOT...LOC 2035Z 266DEG 17KT 4009 7605
$$
NIERENBERG1 follow-up statement
534
WWUS51 KPHI 072119
SVSPHI
SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
519 PM EDT THU JUL 7 2011
PAC029-072130-
/O.CON.KPHI.SV.W.0152.000000T0000Z-110707T2130Z/
CHESTER PA-
519 PM EDT THU JUL 7 2011
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 530 PM EDT
FOR EAST CENTRAL CHESTER COUNTY...
AT 517 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE
HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH. THIS STORM WAS
LOCATED NEAR MALVERN...OR NEAR WEST CHESTER...MOVING SOUTHEAST AT 10
MPH. THIS STORM DOWNED TREES IN WEST WHITELAND TOWNSHIP.
THE SEVERE THUNDERSTORM WILL BE NEAR...
RURAL EASTERN CHESTER COUNTY AT 530 PM EDT
PRECAUTIONARY/PREPAREDNESS ACTIONS...
THIS STORM HAS A HISTORY OF PRODUCING DESTRUCTIVE WINDS AND LARGE
DAMAGING HAIL. SEEK SHELTER NOW INSIDE A STURDY STRUCTURE AND STAY
AWAY FROM WINDOWS!
&&
LAT...LON 4003 7564 4008 7562 4015 7553 4012 7551
4007 7540 4000 7545 4000 7546 3999 7545
3997 7551 3999 7569
TIME...MOT...LOC 2119Z 320DEG 10KT 3999 7552
$$
TFGThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 7, 2:27 PM EDT | Special Weather Statement | PHI | Philadelphia | 93 min |
| Jul 7, 3:05 PM EDT | Special Weather Statement | PHI | Lehigh | 55 min |
| Jul 7, 3:07 PM EDT | Special Weather Statement | PHI | Monroe | 53 min |
| Jul 7, 3:26 PM EDT | Severe Thunderstorm Warning | PHI | Monroe | 64 min |
| Jul 7, 5:12 PM EDT | Severe Thunderstorm Warning | PHI | Chester, Delaware, Montgomery, Philadelphia | 63 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.