Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2011
Severe Thunderstorm Warning 93, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jun 9, 2011, 6:24 PM EDT for Berks County, Chester County, Montgomery County, Pennsylvania. It was in force for 66 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
- Jun 9, 2011, 6:24 PM EDT (22:24 UTC)
- Expired
- Jun 9, 2011, 7:30 PM EDT
- In force
- 66 min
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
Counties Berks County, PA, Chester County, PA, Montgomery County, PA
The radar
The Philadelphia radar (KDIX), 140 km from the middle of the area, began a volume at 22:24 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 |
|---|---|---|---|
| Jun 9, 6:54 PM EDT | TSTM WND DMG | Douglass Twp, PA | WIRES DOWN |
| Jun 9, 7:13 PM EDT | HAIL 0.75 | Gilbertsville, PA |
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 |
|---|---|---|---|
| Jun 9, 2:34 PM EDT | Severe Thunderstorm Watch | SPC | 7 hr |
The nearest sounding before it
Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 10.4 hours before the alert went out and 85 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
- 734 J/kg
- Mixed-layer CIN
- -235 J/kg
- Mixed-layer LCL
- 1935 m above ground
- 0-6 km bulk shear
- 19 kt
- 0-1 km storm-relative helicity
- -20 m²/s²
- 0-3 km storm-relative helicity
- 28 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
905
WUUS51 KPHI 092224
SVRPHI
PAC011-029-091-092330-
/O.NEW.KPHI.SV.W.0093.110609T2224Z-110609T2330Z/
BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
624 PM EDT THU JUN 9 2011
THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A
* SEVERE THUNDERSTORM WARNING FOR...
SOUTHERN BERKS COUNTY IN EASTERN PENNSYLVANIA...
NORTHERN CHESTER COUNTY IN SOUTHEAST PENNSYLVANIA...
THIS INCLUDES THE CITY OF WEST CHESTER...
WESTERN MONTGOMERY COUNTY IN SOUTHEAST PENNSYLVANIA...
* UNTIL 730 PM EDT
* AT 620 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 9 MILES
SOUTH OF WOMELSDORF...OR 14 MILES NORTH OF LANCASTER...AND
MOVING EAST AT 30 TO 35 MPH.
* THE SEVERE THUNDERSTORM WILL BE NEAR...
NEW MORGAN AROUND 650 PM EDT...
BIRDSBORO AROUND 655 PM EDT...
POTTSTOWN AND CEDARVILLE AROUND 710 PM EDT...
GILBERTSVILLE AROUND 715 PM EDT...
ROYERSFORD AROUND 720 PM EDT...
TRAPPE AROUND 725 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.
A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 1000 PM EDT
THURSDAY EVENING FOR NORTHERN DELAWARE AND NORTHEAST MARYLAND AND NEW
JERSEY AND EASTERN PENNSYLVANIA.
&&
LAT...LON 4049 7641 4051 7624 4027 7583 4043 7555
4006 7544 3990 7561 3992 7601 3996 7600
4003 7595 4011 7595 4014 7590 4036 7621
4036 7624 4047 7640
TIME...MOT...LOC 2224Z 267DEG 32KT 4023 7619
$$2 follow-up statements
502
WWUS51 KPHI 092249
SVSPHI
SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
649 PM EDT THU JUN 9 2011
PAC011-029-091-092330-
/O.CON.KPHI.SV.W.0093.000000T0000Z-110609T2330Z/
CHESTER PA-MONTGOMERY PA-BERKS PA-
649 PM EDT THU JUN 9 2011
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 730 PM EDT
FOR SOUTHERN BERKS...WESTERN MONTGOMERY AND NORTHERN CHESTER
COUNTIES...
AT 645 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE
HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH. THIS STORM WAS
LOCATED NEAR FLYING HILLS...OR 6 MILES SOUTH OF READING...MOVING EAST
AT 30 TO 35 MPH.
THE SEVERE THUNDERSTORM WILL BE NEAR...
BIRDSBORO BY 655 PM EDT...
AMITY GARDENS BY 705 PM EDT...
STOWE...SOUTH POTTSTOWN...CEDARVILLE AND KENILWORTH BY 710 PM
EDT...
SANATOGA...POTTSGROVE AND GILBERTSVILLE BY 715 PM EDT...
ROYERSFORD BY 720 PM EDT...
PRECAUTIONARY/PREPAREDNESS ACTIONS...
IN ADDITION TO LARGE HAIL AND DAMAGING WINDS...FREQUENT CLOUD TO
GROUND LIGHTNING IS OCCURRING WITH THIS STORM. MOVE INDOORS
IMMEDIATELY! LIGHTNING IS ONE OF NATURES NUMBER ONE KILLERS.
REMEMBER...IF YOU CAN HEAR THUNDER...YOU ARE CLOSE ENOUGH TO BE
STRUCK BY LIGHTNING.
A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 1000 PM EDT
THURSDAY EVENING FOR NORTHERN DELAWARE AND NORTHEAST MARYLAND AND NEW
JERSEY AND EASTERN PENNSYLVANIA.
&&
LAT...LON 4049 7641 4051 7624 4027 7583 4043 7555
4006 7544 3990 7561 3992 7601 3996 7600
4003 7595 4011 7595 4014 7590 4036 7621
4036 7624 4047 7640
TIME...MOT...LOC 2249Z 267DEG 32KT 4024 7590
$$686
WWUS51 KPHI 092311
SVSPHI
SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
711 PM EDT THU JUN 9 2011
PAC011-029-091-092330-
/O.CON.KPHI.SV.W.0093.000000T0000Z-110609T2330Z/
CHESTER PA-MONTGOMERY PA-BERKS PA-
711 PM EDT THU JUN 9 2011
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 730 PM EDT
FOR SOUTHEASTERN BERKS...WESTERN MONTGOMERY AND NORTHERN CHESTER
COUNTIES...
AT 706 PM EDT...A SEVERE THUNDERSTORM WAS REPORTED CAPABLE OF
PRODUCING QUARTER SIZE HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.
THIS STORM WAS LOCATED NEAR STOWE...OR 13 MILES SOUTHEAST OF
READING...MOVING EAST AT 30 TO 35 MPH.
THE SEVERE THUNDERSTORM WILL BE NEAR...
ROYERSFORD...SPRING CITY AND 8 MILES NORTH OF PHOENIXVILLE BY 720
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.
A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 1000 PM EDT
THURSDAY EVENING FOR NORTHERN DELAWARE AND NORTHEAST MARYLAND AND NEW
JERSEY AND EASTERN PENNSYLVANIA.
&&
LAT...LON 4024 7602 4032 7591 4027 7583 4043 7555
4006 7544 3990 7561 3992 7601 3996 7600
4003 7595 4011 7595 4014 7590
TIME...MOT...LOC 2311Z 267DEG 32KT 4025 7564
$$The office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 9, 4:41 PM EDT | Severe Thunderstorm Warning | PHI | Carbon, Monroe | 64 min |
| Jun 9, 5:43 PM EDT | Severe Thunderstorm Warning | PHI | Berks, Carbon, Lehigh, Monroe, Northampton | 62 min |
| Jun 9, 6:44 PM EDT | Severe Thunderstorm Warning | PHI | Berks, Bucks, Carbon, Chester, Lehigh, Monroe and 2 more | 61 min |
| Jun 9, 7:27 PM EDT | Severe Thunderstorm Warning | PHI | Berks, Chester, Delaware, Montgomery | 48 min |
| Jun 9, 7:42 PM EDT | Severe Thunderstorm Warning | PHI | Bucks, Chester, Montgomery, Philadelphia | 33 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.