Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 78, NWS Philadelphia/Mount Holly

June 1, 2011Berks County, Chester County, Lehigh County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jun 1, 2011, 2:42 PM EDT for Berks County, Chester County, Lehigh County, Pennsylvania. It was in force for 52 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
Jun 1, 2011, 2:42 PM EDT (18:42 UTC)
Expired
Jun 1, 2011, 3:34 PM EDT
In force
52 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon

Counties Berks County, PA, Chester County, PA, Lehigh County, PA

The radar

The Philadelphia radar (KDIX), 147 km from the middle of the area, began a volume at 18:43 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.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Jun 1, 12:58 PM EDTTornado WatchSPC7 hr

The nearest sounding before it

Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 6.7 hours before the alert went out and 116 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.

Skew-T log-pSkew-T log-p diagram, Phillips Aaf/Abe, MD at 12:00Z on 2011-06-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2843 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Phillips Aaf/Abe, MD at 12:00Z on 2011-06-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 319 square meters per square second.1939587897117136156Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
2843 J/kg
Mixed-layer CIN
-97 J/kg
Mixed-layer LCL
1042 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
319 m²/s²
0-3 km storm-relative helicity
336 m²/s²
Significant tornado parameter
0.0
Supercell composite
4.1

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

039 
WUUS51 KPHI 011842
SVRPHI
PAC011-029-077-011945-
/O.NEW.KPHI.SV.W.0078.110601T1842Z-110601T1945Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
242 PM EDT WED JUN 1 2011

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  BERKS COUNTY IN EASTERN PENNSYLVANIA...
  THIS INCLUDES THE CITY OF READING...
  LEHIGH COUNTY IN EASTERN PENNSYLVANIA...
  EXTREME NORTH CENTRAL CHESTER COUNTY IN SOUTHEAST PENNSYLVANIA...

* UNTIL 345 PM EDT

* AT 238 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  AN AREA  OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING QUARTER 
  SIZE HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.  THESE STORMS
  WERE   LOCATED ALONG FROM HAMBURG TO 11 MILES WEST OF STRAUSSTOWN
  TO 9 MILES SOUTHWEST OF WOMELSDORF...OR FROM 20 MILES NORTH OF
  READING TO 28 MILES NORTHWEST OF   READING TO 18 MILES NORTH OF
  LANCASTER...AND MOVING EAST AT 35 MPH.

* SEVERE THUNDERSTORMS WILL BE NEAR...
  WOMELSDORF AROUND 250 PM EDT...
  STRAUSSTOWN AROUND 255 PM EDT...
  WANAMAKERS...WERNERSVILLE AND BERNVILLE AROUND 300 PM EDT...
  SINKING SPRING...LENHARTSVILLE AND HAMBURG AROUND 305 PM EDT...
  WYOMISSING AROUND 310 PM EDT...
  CLAUSSVILLE AROUND 315 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A TORNADO WATCH REMAINS IN EFFECT FOR THE WARNED AREA. IF A TORNADO
IS SPOTTED... ACT QUICKLY AND MOVE TO A PLACE OF SAFETY IN A STURDY
STRUCTURE...SUCH AS A BASEMENT OR SMALL INTERIOR ROOM.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 800 PM EDT WEDNESDAY EVENING
FOR NEW JERSEY AND EASTERN PENNSYLVANIA.

&&

LAT...LON 4051 7643 4054 7618 4060 7605 4059 7603
      4064 7601 4069 7589 4072 7554 4065 7549
      4065 7547 4051 7550 4018 7576 4019 7599
      4036 7621 4036 7624 4049 7644
TIME...MOT...LOC 1841Z 270DEG 30KT 4059 7603 4054 7636
          4030 7630

$$

MPD
2 follow-up statements
703 
WWUS51 KPHI 011914
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
314 PM EDT WED JUN 1 2011

PAC029-011923-
/O.CAN.KPHI.SV.W.0078.000000T0000Z-110601T1945Z/
CHESTER PA-
314 PM EDT WED JUN 1 2011

...THE SEVERE THUNDERSTORM WARNING FOR NORTH CENTRAL CHESTER COUNTY
IS CANCELLED...

A TORNADO WATCH REMAINS IN EFFECT UNTIL 800 PM EDT WEDNESDAY EVENING
FOR NEW JERSEY AND EASTERN PENNSYLVANIA. A SEVERE THUNDERSTORM WATCH
ALSO REMAINS IN EFFECT UNTIL 1000 PM EDT WEDNESDAY EVENING FOR
DELAWARE AND NORTHEASTERN MARYLAND AND SOUTHERN NEW JERSEY.

LAT...LON 4048 7610 4054 7618 4060 7605 4059 7603
      4064 7601 4069 7589 4072 7554 4065 7549
      4065 7547 4051 7550 4043 7556
TIME...MOT...LOC 1913Z 265DEG 33KT 4059 7594

$$

PAC011-077-011945-
/O.CON.KPHI.SV.W.0078.000000T0000Z-110601T1945Z/
BERKS PA-LEHIGH PA-
314 PM EDT WED JUN 1 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 345 PM EDT
FOR LEHIGH AND NORTHERN BERKS COUNTIES...

AT 308 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 PORT CLINTON...OR 18 MILES NORTH OF READING...MOVING
EAST AT 35 MPH.

THE SEVERE THUNDERSTORM WILL BE NEAR...
  WANAMAKERS BY 320 PM EDT...
  6 MILES NORTH OF KUTZTOWN BY 325 PM EDT...
  NEW TRIPOLI BY 330 PM EDT...
  CLAUSSVILLE BY 335 PM EDT...
  SCHNECKSVILLE...NEFFS AND 6 MILES NORTH OF ANCIENT OAKS BY 340 PM
  EDT...
  COFFEETOWN AND FULLERTON BY 345 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A TORNADO WATCH REMAINS IN EFFECT UNTIL 800 PM EDT WEDNESDAY EVENING
FOR NEW JERSEY AND EASTERN PENNSYLVANIA. A SEVERE THUNDERSTORM WATCH
ALSO REMAINS IN EFFECT UNTIL 1000 PM EDT WEDNESDAY EVENING FOR
DELAWARE AND NORTHEASTERN MARYLAND AND SOUTHERN NEW JERSEY.

&&

LAT...LON 4048 7610 4054 7618 4060 7605 4059 7603
      4064 7601 4069 7589 4072 7554 4065 7549
      4065 7547 4051 7550 4043 7556
TIME...MOT...LOC 1913Z 265DEG 33KT 4059 7594

$$

AMC
883 
WWUS51 KPHI 011934
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
334 PM EDT WED JUN 1 2011

PAC011-077-011944-
/O.CAN.KPHI.SV.W.0078.000000T0000Z-110601T1945Z/
BERKS PA-LEHIGH PA-
334 PM EDT WED JUN 1 2011

...THE SEVERE THUNDERSTORM WARNING FOR LEHIGH AND NORTHERN BERKS
COUNTIES IS CANCELLED...

A TORNADO WATCH REMAINS IN EFFECT UNTIL 800 PM EDT WEDNESDAY EVENING
FOR NEW JERSEY AND EASTERN PENNSYLVANIA.

LAT...LON 4048 7610 4054 7618 4060 7605 4059 7603
      4064 7601 4069 7589 4072 7554 4065 7549
      4065 7547 4051 7550 4043 7556
TIME...MOT...LOC 1934Z 265DEG 33KT 4061 7569

$$

MPD

The office that day

Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 1, 12:56 PM EDTSevere Thunderstorm WarningPHICarbon, Monroe60 min
Jun 1, 1:57 PM EDTSevere Thunderstorm WarningPHICarbon, Monroe, Northampton63 min
Jun 1, 3:08 PM EDTSevere Thunderstorm WarningPHIBucks, Lehigh, Northampton16 min
Jun 1, 4:15 PM EDTSevere Thunderstorm WarningPHIBucks45 min
Jun 1, 4:55 PM EDTSevere Thunderstorm WarningPHIChester26 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.