Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2008

Severe Thunderstorm Warning 69, NWS Philadelphia/Mount Holly

June 14, 2008Berks County, Chester County, Montgomery County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jun 14, 2008, 7:05 PM EDT for Berks County, Chester County, Montgomery County, Pennsylvania. It was in force for 70 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
Jun 14, 2008, 7:05 PM EDT (23:05 UTC)
Expired
Jun 14, 2008, 8:15 PM EDT
In force
70 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), 104 km from the middle of the area, began a volume at 23:06 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

TimeReportWhereRemark
Jun 14, 7:10 PM EDTTSTM WND DMGElverson, PATREES AND WIRES DOWN.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 11.1 hours before the alert went out and 200 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, Washington/Dulle, VA at 12:00Z on 2008-06-14Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 92 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, Washington/Dulle, VA at 12:00Z on 2008-06-14The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 125 square meters per square second.1939Sfc1 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
92 J/kg
Mixed-layer CIN
-205 J/kg
Mixed-layer LCL
1369 m above ground
0-6 km bulk shear
18 kt
0-1 km storm-relative helicity
125 m²/s²
0-3 km storm-relative helicity
139 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

000 
WUUS51 KPHI 142305
SVRPHI
PAC011-029-091-150015-
/O.NEW.KPHI.SV.W.0069.080614T2305Z-080615T0015Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
705 PM EDT SAT JUN 14 2008

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTH CENTRAL BERKS COUNTY IN EASTERN PENNSYLVANIA...
  NORTHERN CHESTER COUNTY IN SOUTHEAST PENNSYLVANIA...
  WESTERN MONTGOMERY COUNTY IN SOUTHEAST PENNSYLVANIA...

* UNTIL 815 PM EDT

* AT 704 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING PENNY SIZE HAIL...AND
  DAMAGING WINDS TO 60 MPH.  THIS STORM WAS LOCATED NEAR
  ELVERSON...OR ABOUT 15 MILES SOUTH OF READING...AND MOVING EAST AT
  20 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  ELVERSON BY 710 PM...
  GLENMOORE BY 720 PM...
  PUGHTOWN BY 735 PM...
  LIONVILLE BY 740 PM...
  CHESTER SPRINGS BY 745 PM...
  PHOENIXVILLE BY 800 PM...

THUNDERSTORMS ARE CAPABLE OF PRODUCING HEAVY RAINFALL WHICH MAY
RESULT IN LOCALIZED AREAS OF FLOODING. DO NOT DRIVE IN AREAS WHERE
WATER IS CROSSING THE ROAD.

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 NUMBER ONE KILLERS.
REMEMBER...IF YOU CAN HEAR THUNDER...YOU ARE CLOSE ENOUGH TO BE
STRUCK BY LIGHTNING.

LAT...LON 4025 7588 4032 7540 4001 7543 4000 7546
      3999 7545 3998 7547 4004 7591
TIME...MOT...LOC 2305Z 277DEG 16KT 4012 7585

$$

TFG
1 follow-up statement
000 
WWUS51 KPHI 142334
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
733 PM EDT SAT JUN 14 2008

PAC011-142343-
/O.CAN.KPHI.SV.W.0069.000000T0000Z-080615T0015Z/
BERKS PA-
733 PM EDT SAT JUN 14 2008

...THE SEVERE THUNDERSTORM WARNING FOR SOUTH CENTRAL BERKS COUNTY IS
CANCELLED...

THE SEVERE THUNDERSTORM HAS MOVED EAST OF THE COUNTY.

LAT...LON 4029 7565 4029 7562 4032 7544 4031 7540
      4002 7543 4000 7546 3998 7547 3998 7551
      3999 7555 4003 7587
TIME...MOT...LOC 2333Z 277DEG 16KT 4010 7569

$$

PAC029-091-150015-
/O.CON.KPHI.SV.W.0069.000000T0000Z-080615T0015Z/
CHESTER PA-MONTGOMERY PA-
733 PM EDT SAT JUN 14 2008

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 815 PM EDT
FOR WESTERN MONTGOMERY AND NORTHEASTERN CHESTER COUNTIES...

AT 728 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING PENNY SIZE
HAIL...AND DAMAGING WINDS TO 60 MPH.  THIS STORM WAS
LOCATED NEAR GLENMOORE...OR 19 MILES SOUTHEAST OF READING...MOVING
EAST AT 18 MPH. ANOTHER SEVERE STORM WAS JUST SOUTH OF POTTSTOWN.

THE SEVERE THUNDERSTORM WILL BE NEAR...
  LIONVILLE BY 740 PM EDT...
  CHESTER SPRINGS AND EXTON BY 745 PM EDT...
  PHOENIXVILLE BY 800 PM EDT...
  MALVERN BY 805 PM EDT...
  VALLEY FORGE AND PAOLI BY 810 PM EDT...
  CHESTERBROOK AND DEVON-BERWYN BY 815 PM EDT...

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.

THIS STORM HAS DOWNED TREES ALREADY IN CHESTER COUNTY.
SEEK SHELTER NOW INSIDE A STURDY STRUCTURE AND STAY AWAY FROM WINDOWS

LAT...LON 4029 7565 4029 7562 4032 7544 4031 7540
      4002 7543 4000 7546 3998 7547 3998 7551
      3999 7555 4003 7587
TIME...MOT...LOC 2333Z 277DEG 16KT 4010 7569

$$

TFG

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 14, 2:23 PM EDTFlash Flood WarningPHIMonroe3 hr
Jun 14, 3:02 PM EDTSevere Thunderstorm WarningPHIMonroe58 min
Jun 14, 4:26 PM EDTSevere Thunderstorm WarningPHICarbon, Monroe, Northampton64 min
Jun 14, 4:49 PM EDTFlash Flood WarningPHICarbon5 hr
Jun 14, 5:07 PM EDTSevere Thunderstorm WarningPHICarbon, Monroe53 min
Jun 14, 5:18 PM EDTSevere Thunderstorm WarningPHICarbon, Monroe57 min
Jun 14, 6:15 PM EDTSevere Thunderstorm WarningPHIChester75 min
Jun 14, 6:28 PM EDTFlash Flood WarningPHIChester60 min
Jun 14, 6:48 PM EDTFlash Flood WarningPHICarbon, Monroe3 hr
Jun 14, 7:42 PM EDTSevere Thunderstorm WarningPHIBucks, Chester, Montgomery63 min
Jun 14, 7:56 PM EDTSevere Thunderstorm WarningPHIBucks, Delaware, Philadelphia79 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2008Every severe thunderstorm warning in 2008

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.