Alert archive / New Jersey / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 99, NWS Philadelphia/Mount Holly

June 9, 20116 counties in New Jersey; 4 counties in Pennsylvania; New Castle County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jun 9, 2011, 8:10 PM EDT for 6 counties in New Jersey; 4 counties in Pennsylvania; New Castle County, Delaware. It was in force for 65 min. 19 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, 8:10 PM EDT (00:10 UTC)
Expired
Jun 9, 2011, 9:15 PM EDT
In force
65 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon

Counties New Castle County, DE, Burlington County, NJ, Camden County, NJ, Cumberland County, NJ, Gloucester County, NJ, Mercer County, NJ, Salem County, NJ, Bucks County, PA, Delaware County, PA, Montgomery County, PA, Philadelphia County, PA

The radar

The Dover AFB radar (KDOX), 82 km from the middle of the area, began a volume at 00:13 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 9, 8:10 PM EDTTSTM WND DMGBensalem, PATREE DOWN... KDIX DOPPLER RADAR ESTIMATED 76 MPH WINDS AT 2000 FEET
Jun 9, 8:10 PM EDTTSTM WND DMGPhiladelphia, PATREE FELL INTO 3 STORY DWELLING.
Jun 9, 8:13 PM EDTHAIL 0.25Boothwyn, PA
Jun 9, 8:14 PM EDTTSTM WND DMGPhiladelphia, PATREES AND WIRES DOWN.
Jun 9, 8:15 PM EDTHAIL 0.75Clifton Heights, PA
Jun 9, 8:15 PM EDTHAIL 0.75Drexel Hill, PA
Jun 9, 8:15 PM EDTHAIL 0.75Springfield, PA
Jun 9, 8:17 PM EDTHAIL 0.25Wilmington, DENEW CASTLE COUNTY AIRPORT
Jun 9, 8:18 PM EDTTSTM WND DMGMerchantville, NJ*** 1 INJ *** TREE FELL ON TO CAR.
Jun 9, 8:18 PM EDTHAIL 0.88Boothwyn, PA
Jun 9, 8:21 PM EDTTSTM WND GST 58Philadelphia, PAPHILADELPHIA INTERNATIONAL AIRPORT
Jun 9, 8:21 PM EDTHAIL 0.75Sharon Hill, PA
Jun 9, 8:22 PM EDTHAIL 0.75Lansdowne, PA
Jun 9, 8:24 PM EDTHAIL 0.75Drexel Hill, PA
Jun 9, 8:30 PM EDTTSTM WND DMGMount Laurel, NJTREES DOWN WITH GUST FRONT.
Jun 9, 8:30 PM EDTHAIL 0.25Philadelphia Sports Com, PACITIZENS BANK PARK
Jun 9, 8:31 PM EDTTSTM WND GST 72Pennsville, NJ
Jun 9, 8:33 PM EDTHAIL 0.75Lansdowne, PA
Jun 9, 8:45 PM EDTTSTM WND DMGBlackwood, NJLARGE BRANCHES DOWN

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.

IssuedProductOfficeLasted
Jun 9, 2:34 PM EDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Wallops Is Stn, VA (KWAL), launched 00:00Z, 0.2 hours before the alert went out and 181 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, Wallops Is Stn, VA at 00:00Z on 2011-06-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1702 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Wallops Is Stn, VA at 00:00Z on 2011-06-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 26 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
1702 J/kg
Mixed-layer CIN
-139 J/kg
Mixed-layer LCL
1829 m above ground
0-6 km bulk shear
15 kt
0-1 km storm-relative helicity
26 m²/s²
0-3 km storm-relative helicity
-9 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.

700 
WUUS51 KPHI 100010
SVRPHI
DEC003-NJC005-007-011-015-021-033-PAC017-045-091-101-100115-
/O.NEW.KPHI.SV.W.0099.110610T0010Z-110610T0115Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
810 PM EDT THU JUN 9 2011

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  WESTERN MERCER COUNTY IN CENTRAL NEW JERSEY...
  THIS INCLUDES THE CITY OF TRENTON...
  NEW CASTLE COUNTY IN NORTHERN DELAWARE...
  THIS INCLUDES THE CITIES OF...WILMINGTON...NEWARK...
  SOUTHEASTERN BUCKS COUNTY IN SOUTHEAST PENNSYLVANIA...
  DELAWARE COUNTY IN SOUTHEAST PENNSYLVANIA...
  SOUTHEASTERN MONTGOMERY COUNTY IN SOUTHEAST PENNSYLVANIA...
  PHILADELPHIA COUNTY IN SOUTHEAST PENNSYLVANIA...
  THIS INCLUDES THE CITY OF PHILADELPHIA...
  BURLINGTON COUNTY IN SOUTHERN NEW JERSEY...
  CAMDEN COUNTY IN SOUTHERN NEW JERSEY...
  THIS INCLUDES THE CITY OF CAMDEN...
  NORTHWESTERN CUMBERLAND COUNTY IN SOUTHERN NEW JERSEY...
  GLOUCESTER COUNTY IN SOUTHERN NEW JERSEY...
  SALEM COUNTY IN SOUTHERN NEW JERSEY...

* UNTIL 915 PM EDT

* AT 805 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING QUARTER SIZE
  HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.  THESE STORMS WERE
  LOCATED ALONG A LINE EXTENDING FROM NEWTOWN TO NEWARK...OR ALONG A
  LINE EXTENDING FROM 9 MILES WEST OF TRENTON TO NEWARK...AND MOVING
  SOUTHEAST AT 35 MPH.

* SEVERE THUNDERSTORMS WILL BE NEAR...
  MOUNT PLEASANT...WISSINOMING...TACONY AND SOUTH PHILADELPHIA AROUND
  815 PM EDT...
  TRENTON...ANDALUSIA...SAINT GEORGES AND TULLYTOWN AROUND 820 PM
  EDT...
  BORDENTOWN AND WHITE HORSE AROUND 825 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 SOUTHEAST PENNSYLVANIA.

&&

LAT...LON 3929 7528 3934 7535 3933 7537 3958 7556
      3942 7553 3938 7552 3947 7578 3970 7579
      4040 7478 3991 7448
TIME...MOT...LOC 0010Z 314DEG 31KT 4022 7489 3964 7568

$$

AMC
3 follow-up statements
450 
WWUS51 KPHI 100033
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
833 PM EDT THU JUN 9 2011

PAC091-100042-
/O.CAN.KPHI.SV.W.0099.000000T0000Z-110610T0115Z/
MONTGOMERY PA-
833 PM EDT THU JUN 9 2011

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN MONTGOMERY COUNTY
IS CANCELLED...

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 1000 PM EDT
THURSDAY EVENING FOR NORTHERN DELAWARE AND NORTHEAST MARYLAND AND NEW
JERSEY AND SOUTHEAST PENNSYLVANIA.

LAT...LON 3929 7528 3934 7538 3954 7553 3958 7554
      3958 7556 3951 7557 3951 7555 3946 7554
      3949 7556 3946 7558 3943 7553 3938 7552
      3947 7578 3964 7577 3966 7575 4025 7471
      4024 7469 3991 7448
TIME...MOT...LOC 0032Z 314DEG 31KT 4009 7471 3951 7550

$$

DEC003-NJC005-007-011-015-021-033-PAC017-045-101-100115-
/O.CON.KPHI.SV.W.0099.000000T0000Z-110610T0115Z/
SALEM NJ-CUMBERLAND NJ-CAMDEN NJ-GLOUCESTER NJ-MERCER NJ-DELAWARE PA-
PHILADELPHIA PA-BUCKS PA-NEW CASTLE DE-BURLINGTON NJ-
833 PM EDT THU JUN 9 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 915 PM EDT
FOR BURLINGTON...NEW CASTLE...SOUTHEASTERN BUCKS...SOUTHERN
PHILADELPHIA...SOUTHEASTERN DELAWARE...SOUTH CENTRAL MERCER...
GLOUCESTER...CAMDEN...NORTHWESTERN CUMBERLAND AND SALEM COUNTIES...

AT 831 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING QUARTER
SIZE HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.  THESE STORMS
WERE LOCATED ALONG A LINE EXTENDING FROM FIELDSBORO TO HANCOCKS
BRIDGE...OR ALONG A LINE EXTENDING FROM 9 MILES SOUTH OF TRENTON TO
12 MILES EAST OF MIDDLETOWN...MOVING SOUTHEAST AT 35 MPH.

SEVERE THUNDERSTORMS WILL BE NEAR...
  WRIGHTSTOWN...TURNERSVILLE...PINE VALLEY AND PINE HILL BY 840 PM
  EDT...
  MCGUIRE AFB...SICKLERVILLE...NEWPORT MEADOWS AND MARLTON LAKES BY
  845 PM EDT...
  MONROE TOWNSHIP AND FRANKLINVILLE BY 850 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS LINE OF STORMS. 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 SOUTHEAST PENNSYLVANIA.

&&

LAT...LON 3929 7528 3934 7538 3954 7553 3958 7554
      3958 7556 3951 7557 3951 7555 3946 7554
      3949 7556 3946 7558 3943 7553 3938 7552
      3947 7578 3964 7577 3966 7575 4025 7471
      4024 7469 3991 7448
TIME...MOT...LOC 0032Z 314DEG 31KT 4009 7471 3951 7550

$$
519 
WWUS51 KPHI 100051
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
851 PM EDT THU JUN 9 2011

DEC003-NJC021-PAC017-045-101-100101-
/O.CAN.KPHI.SV.W.0099.000000T0000Z-110610T0115Z/
MERCER NJ-DELAWARE PA-PHILADELPHIA PA-BUCKS PA-NEW CASTLE DE-
851 PM EDT THU JUN 9 2011

...THE SEVERE THUNDERSTORM WARNING FOR NEW CASTLE...SOUTHEASTERN
BUCKS...SOUTHERN PHILADELPHIA...SOUTHEASTERN DELAWARE AND SOUTH
CENTRAL MERCER COUNTIES IS CANCELLED...

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 1000 PM EDT
THURSDAY EVENING FOR NORTHERN DELAWARE AND NORTHEAST MARYLAND AND NEW
JERSEY AND SOUTHEAST PENNSYLVANIA.

LAT...LON 3972 7473 3973 7474 3962 7485 3929 7528
      3934 7535 3933 7536 3934 7539 3959 7554
      3965 7549 4015 7471 3991 7448
TIME...MOT...LOC 0051Z 304DEG 24KT 4009 7463 3951 7542

$$

NJC005-007-011-015-033-100115-
/O.CON.KPHI.SV.W.0099.000000T0000Z-110610T0115Z/
SALEM NJ-CUMBERLAND NJ-CAMDEN NJ-GLOUCESTER NJ-BURLINGTON NJ-
851 PM EDT THU JUN 9 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 915 PM EDT
FOR BURLINGTON...GLOUCESTER...CAMDEN...NORTHWESTERN CUMBERLAND AND
SALEM COUNTIES...

AT 848 PM EDT...A LINE OF SEVERE THUNDERSTORMS WAS REPORTED CAPABLE
OF PRODUCING QUARTER SIZE HAIL...AND DAMAGING WINDS IN EXCESS OF 60
MPH.  THESE STORMS WERE LOCATED ALONG A LINE EXTENDING FROM
GEORGETOWN TO HANCOCKS BRIDGE...OR ALONG A LINE EXTENDING FROM 10
MILES SOUTHEAST OF TRENTON TO 15 MILES EAST OF MIDDLETOWN...MOVING
SOUTHEAST AT 30 MPH.

SEVERE THUNDERSTORMS WILL BE NEAR...
  NEWPORT MEADOWS...MARLTON LAKES...PEMBERTON HEIGHTS AND PEMBERTON
  BY 900 PM EDT...
  SICKLERVILLE...FRANKLINVILLE...ATCO AND WILLIAMSTOWN BY 905 PM
  EDT...
  BRIDGETON AND TABERNACLE BY 910 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 1000 PM EDT
THURSDAY EVENING FOR NORTHERN DELAWARE AND NORTHEAST MARYLAND AND NEW
JERSEY AND SOUTHEAST PENNSYLVANIA.

&&

LAT...LON 3972 7473 3973 7474 3962 7485 3929 7528
      3934 7535 3933 7536 3934 7539 3959 7554
      3965 7549 4015 7471 3991 7448
TIME...MOT...LOC 0051Z 304DEG 24KT 4009 7463 3951 7542

$$

AMC
561 
WWUS51 KPHI 100113
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
913 PM EDT THU JUN 9 2011

NJC005-007-011-015-033-100122-
/O.EXP.KPHI.SV.W.0099.000000T0000Z-110610T0115Z/
SALEM NJ-CUMBERLAND NJ-CAMDEN NJ-GLOUCESTER NJ-BURLINGTON NJ-
913 PM EDT THU JUN 9 2011

...THE SEVERE THUNDERSTORM WARNING FOR BURLINGTON...GLOUCESTER...
CAMDEN...NORTHWESTERN CUMBERLAND AND SALEM COUNTIES WILL EXPIRE AT
915 PM EDT...

THUNDERSTORMS WILL CONTINUE TO MOVE ACROSS PARTS OF SOUTHERN NEW 
JERSEY FOR A COUPLE MORE HOURS BUT NONE APPEAR TO BE SEVERE AT THIS 
TIME. 

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 1000 PM EDT
THURSDAY EVENING FOR NORTHERN DELAWARE AND NORTHEAST MARYLAND AND NEW
JERSEY AND SOUTHEAST PENNSYLVANIA.

LAT...LON 3972 7473 3973 7474 3962 7485 3929 7528
      3934 7535 3933 7536 3934 7539 3959 7554
      3965 7549 4015 7471 3991 7448
TIME...MOT...LOC 0112Z 304DEG 24KT 4001 7448 3943 7527

$$

AMC

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 9, 10:05 PM EDTSpecial Marine WarningPHI40 min
Jun 9, 10:13 PM EDTSevere Thunderstorm WarningPHICumberland, Gloucester, Salem47 min
Jun 9, 10:32 PM EDTSevere Thunderstorm WarningPHIAtlantic, Burlington, Camden, Cumberland, Gloucester, Salem58 min
Jun 9, 10:52 PM EDTSpecial Marine WarningPHI83 min
Jun 9, 10:59 PM EDTSevere Thunderstorm WarningPHIAtlantic, Burlington, Camden, Cape May, Cumberland, Ocean46 min
Jun 9, 11:24 PM EDTSpecial Marine WarningPHI96 min
Jun 10, 6:14 PM EDTSpecial Weather StatementPHICumberland61 min
Jun 10, 7:07 PM EDTSpecial Weather StatementPHICumberland53 min
Jun 9, 9:41 PM EDTSpecial Weather StatementPHIKent64 min
Jun 9, 9:59 PM EDTSpecial Weather StatementPHIKent31 min
Jun 9, 11:29 PM EDTSpecial Weather StatementPHIKent61 min
Jun 10, 12:16 AM EDTSevere Thunderstorm WarningPHIKent59 min
Jun 10, 1:01 AM EDTSpecial Weather StatementPHIKent, Sussex119 min
Jun 10, 5:27 PM EDTSpecial Weather StatementPHISussex63 min

Nearby

Severe Thunderstorm Warnings in New Jersey, 2011Severe Thunderstorm Warnings in Pennsylvania, 2011Severe Thunderstorm Warnings in Delaware, 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.