Alert archive / New Jersey / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 231, NWS Philadelphia/Mount Holly

September 18, 20129 counties in New Jersey; Bucks County, Montgomery County, Philadelphia County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Sep 18, 2012, 6:00 PM EDT for 9 counties in New Jersey; Bucks County, Montgomery County, Philadelphia County, Pennsylvania. It was in force for 60 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: Sep 18, 2012, 6:00 PM EDT (22:00 UTC)
Expired: Sep 18, 2012, 7:00 PM EDT
In force: 60 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon

Counties Burlington County, NJ, Camden County, NJ, Gloucester County, NJ, Hunterdon County, NJ, Mercer County, NJ, Middlesex County, NJ, Monmouth County, NJ, Morris County, NJ, Somerset County, NJ, Bucks County, PA, Montgomery County, PA, Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 74 km from the middle of the area, began a volume at 22:03 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
Sep 18, 6:10 PM EDT	TSTM WND DMG	Deptford Twp, NJ	TREE DOWN ON A GARAGE.
Sep 18, 6:56 PM EDT	TSTM WND DMG	East Hanover, NJ	SOME TREES DOWN THROUGHOUT COUNTY

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
Sep 18, 12:10 PM EDT	Tornado Watch	SPC	9 hr

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 10.0 hours before the alert went out and 143 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 114 J/kg
Mixed-layer CIN: -4 J/kg
Mixed-layer LCL: 721 m above ground
0-6 km bulk shear: 45 kt
0-1 km storm-relative helicity: 224 m²/s²
0-3 km storm-relative helicity: 267 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 0.6

Open this sounding in Storm Lab

The text

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

118 
WUUS51 KPHI 182200
SVRPHI
NJC005-007-015-019-021-023-025-027-035-PAC017-091-101-182300-
/O.NEW.KPHI.SV.W.0231.120918T2200Z-120918T2300Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
600 PM EDT TUE SEP 18 2012

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  MERCER COUNTY IN CENTRAL NEW JERSEY...
  THIS INCLUDES THE CITY OF TRENTON...
  SOUTHWESTERN MONMOUTH COUNTY IN CENTRAL NEW JERSEY...
  WESTERN MIDDLESEX COUNTY IN NORTHERN NEW JERSEY...
  THIS INCLUDES THE CITY OF NEW BRUNSWICK...
  SOUTHERN MORRIS COUNTY IN NORTHERN NEW JERSEY...
  SOMERSET COUNTY IN NORTHERN NEW JERSEY...
  THIS INCLUDES THE CITY OF SOMERVILLE...
  HUNTERDON COUNTY IN NORTHWEST NEW JERSEY...
  SOUTHEASTERN BUCKS COUNTY IN SOUTHEAST PENNSYLVANIA...
  SOUTHEASTERN MONTGOMERY COUNTY IN SOUTHEAST PENNSYLVANIA...
  PHILADELPHIA COUNTY IN SOUTHEAST PENNSYLVANIA...
  THIS INCLUDES THE CITY OF PHILADELPHIA...
  WESTERN BURLINGTON COUNTY IN SOUTHERN NEW JERSEY...
  CAMDEN COUNTY IN SOUTHERN NEW JERSEY...
  THIS INCLUDES THE CITIES OF...GLOUCESTER CITY...CAMDEN...
  CENTRAL GLOUCESTER COUNTY IN SOUTHERN NEW JERSEY...

* UNTIL 700 PM EDT

* AT 554 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING WINDS IN
  EXCESS OF 60 MPH.  THESE STORMS WERE LOCATED ALONG A LINE EXTENDING
  FROM CALIFON TO BEN FRANKLIN BRIDGE...OR ALONG A LINE EXTENDING
  FROM 18 MILES EAST OF EASTON TO CAMDEN...AND MOVING EAST AT 40 MPH.

THIS LINE OF HEAVY SHOWERS AND STORMS HAVE A HISTORY OF KNOCKING SOME
TREES DOWN IN PLACES ALONG ITS PATH.

* SEVERE THUNDERSTORMS WILL BE NEAR...
  WISSINOMING...RICHBORO...LEBANON AND CAMDEN AROUND 605 PM EDT...
  LONG VALLEY...SICKLERVILLE...MAGNOLIA AND TACONY AROUND 610 PM
  EDT...
  LINDENWOLD AND ANDALUSIA AROUND 615 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS LINE OF STORMS MAY CONTAIN LITTLE OR NO LIGHTNING. 
DO NOT WAIT TO HEAR THUNDER BEFORE TAKING COVER. SEEK SHELTER 
IMMEDIATELY INSIDE A STURDY STRUCTURE AND STAY AWAY FROM WINDOWS.

PLEASE REPORT HAIL OR STRONG WINDS TO THE NATIONAL WEATHER SERVICE BY
CALLING TOLL FREE...1-877-633-6772...WHEN YOU CAN DO SO SAFELY.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 700 PM EDT TUESDAY EVENING
FOR DELAWARE AND NORTHEASTERN MARYLAND AND NEW JERSEY AND EASTERN
PENNSYLVANIA.

&&

LAT...LON 4090 7427 4090 7433 4074 7436 4067 7445
      4067 7440 4061 7443 4061 7433 3973 7467
      3968 7526 4071 7497 4078 7490 4098 7428
TIME...MOT...LOC 2159Z 256DEG 35KT 4074 7484 3995 7515

$$

GORSE

2 follow-up statements

439 
WWUS51 KPHI 182225
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
625 PM EDT TUE SEP 18 2012

PAC091-182234-
/O.CAN.KPHI.SV.W.0231.000000T0000Z-120918T2300Z/
MONTGOMERY PA-
625 PM EDT TUE SEP 18 2012

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

PLEASE REPORT HAIL OR STRONG WINDS TO THE NATIONAL WEATHER SERVICE BY
CALLING TOLL FREE...1-877-633-6772...WHEN YOU CAN DO SO SAFELY.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 700 PM EDT TUESDAY EVENING
FOR DELAWARE AND NORTHEASTERN MARYLAND AND NEW JERSEY AND EASTERN
PENNSYLVANIA.

LAT...LON 4090 7433 4074 7436 4067 7445 4067 7440
      4061 7443 4061 7433 4008 7453 4008 7455
      4006 7454 3973 7467 3969 7518 4011 7505
      4014 7501 4015 7504 4081 7482 4098 7428
      4090 7427
TIME...MOT...LOC 2224Z 239DEG 33KT 4081 7459 4029 7476
          3971 7509

$$

NJC005-007-015-019-021-023-025-027-035-PAC017-101-182300-
/O.CON.KPHI.SV.W.0231.000000T0000Z-120918T2300Z/
CAMDEN NJ-HUNTERDON NJ-MERCER NJ-MORRIS NJ-SOMERSET NJ-BUCKS PA-
PHILADELPHIA PA-GLOUCESTER NJ-MIDDLESEX NJ-BURLINGTON NJ-MONMOUTH NJ-
625 PM EDT TUE SEP 18 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 700 PM EDT
FOR SOUTHWESTERN MONMOUTH...WESTERN BURLINGTON...WESTERN MIDDLESEX...
CENTRAL GLOUCESTER...NORTHEASTERN PHILADELPHIA...SOUTHEASTERN
BUCKS...SOMERSET...SOUTHERN MORRIS...MERCER...EASTERN HUNTERDON AND
CAMDEN COUNTIES...

AT 620 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING
WINDS IN EXCESS OF 60 MPH.  THESE STORMS WERE LOCATED ALONG A LINE
EXTENDING FROM MENDHAM TO EWING TO GLASSBORO...OR ALONG A LINE
EXTENDING FROM 15 MILES NORTH OF SOMERVILLE TO TRENTON TO 14 MILES
SOUTH OF GLOUCESTER CITY...MOVING NORTHEAST AT 40 MPH.

SOME TREES HAVE BEEN SPORADICALLY KNOCKED DOWN BY THIS LINE EARLIER.

SEVERE THUNDERSTORMS WILL BE NEAR...
  VICTORY GARDENS...DOVER...VOORHEES AND MOUNT LAUREL BY 630 PM
  EDT...
  ROCKAWAY...SICKLERVILLE...MILLINGTON AND MORRISTOWN BY 635 PM
  EDT...
  MOUNTAIN LAKES AND BOONTON BY 640 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS LINE OF STORMS MAY CONTAIN LITTLE OR NO LIGHTNING. DO NOT WAIT 
FOR THUNDER BEFORE TAKING COVER. SEEK SHELTER IMMEDIATELY INSIDE A 
STURDY STRUCTURE AND STAY AWAY FROM WINDOWS.

PLEASE REPORT HAIL OR STRONG WINDS TO THE NATIONAL WEATHER SERVICE BY
CALLING TOLL FREE...1-877-633-6772...WHEN YOU CAN DO SO SAFELY.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 700 PM EDT TUESDAY EVENING
FOR DELAWARE AND NORTHEASTERN MARYLAND AND NEW JERSEY AND EASTERN
PENNSYLVANIA.

&&

LAT...LON 4090 7433 4074 7436 4067 7445 4067 7440
      4061 7443 4061 7433 4008 7453 4008 7455
      4006 7454 3973 7467 3969 7518 4011 7505
      4014 7501 4015 7504 4081 7482 4098 7428
      4090 7427
TIME...MOT...LOC 2224Z 239DEG 33KT 4081 7459 4029 7476
          3971 7509

$$

GORSE

631 
WWUS51 KPHI 182238
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
638 PM EDT TUE SEP 18 2012

PAC101-182248-
/O.CAN.KPHI.SV.W.0231.000000T0000Z-120918T2300Z/
PHILADELPHIA PA-
638 PM EDT TUE SEP 18 2012

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN PHILADELPHIA
COUNTY IS CANCELLED...

THE LINE OF STORMS THAT PROMPTED THE WARNING HAVE CLEARED THE AREA, 
THEREFORE THE WARNING HAS BEEN CANCELLED.

PLEASE REPORT HAIL OR STRONG WINDS TO THE NATIONAL WEATHER SERVICE BY
CALLING TOLL FREE...1-877-633-6772...WHEN YOU CAN DO SO SAFELY.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 900 PM EDT TUESDAY EVENING
FOR SOUTHERN DELAWARE AND NEW JERSEY.

LAT...LON 4090 7433 4074 7436 4067 7445 4067 7440
      4061 7443 4061 7433 3973 7467 3970 7514
      4009 7495 4085 7469 4098 7428 4090 7427
TIME...MOT...LOC 2238Z 239DEG 33KT 4086 7448 4034 7465
          3977 7498

$$

NJC005-007-015-019-021-023-025-027-035-PAC017-182300-
/O.CON.KPHI.SV.W.0231.000000T0000Z-120918T2300Z/
CAMDEN NJ-HUNTERDON NJ-MERCER NJ-MORRIS NJ-SOMERSET NJ-BUCKS PA-
GLOUCESTER NJ-MIDDLESEX NJ-BURLINGTON NJ-MONMOUTH NJ-
638 PM EDT TUE SEP 18 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 700 PM EDT
FOR SOUTHWESTERN MONMOUTH...WESTERN BURLINGTON...WESTERN MIDDLESEX...
CENTRAL GLOUCESTER...SOUTHEASTERN BUCKS...SOMERSET...SOUTHERN
MORRIS...MERCER...SOUTHEASTERN HUNTERDON AND CAMDEN COUNTIES...

AT 633 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING
WINDS IN EXCESS OF 60 MPH.  THESE STORMS WERE LOCATED ALONG A LINE
EXTENDING FROM VICTORY GARDENS TO LAWRENCEVILLE TO TURNERSVILLE...OR
ALONG A LINE EXTENDING FROM 18 MILES SOUTHEAST OF NEWTON TO 7 MILES
NORTHEAST OF TRENTON TO 11 MILES SOUTHEAST OF GLOUCESTER CITY...
MOVING NORTHEAST AT 40 MPH.

SEVERE THUNDERSTORMS WILL BE NEAR...
  BOONTON...MARLTON LAKES...LUMBERTON AND JACKSONVILLE BY 645 PM
  EDT...
  SOUTH BRUNSWICK...EDINBURG...COLUMBUS AND YARDVILLE-GROVEVILLE BY
  650 PM EDT...
  PEQUANNOCK TOWNSHIP AND SHAMONG BY 655 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS LINE OF STORMS MAY CONTAIN LITTLE OR NO LIGHTNING. DO NOT WAIT 
FOR THUNDER BEFORE TAKING COVER. SEEK SHELTER IMMEDIATELY INSIDE A 
STURDY STRUCTURE AND STAY AWAY FROM WINDOWS.

PLEASE REPORT HAIL OR STRONG WINDS TO THE NATIONAL WEATHER SERVICE BY
CALLING TOLL FREE...1-877-633-6772...WHEN YOU CAN DO SO SAFELY.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 900 PM EDT TUESDAY EVENING
FOR SOUTHERN DELAWARE AND NEW JERSEY.

&&

LAT...LON 4090 7433 4074 7436 4067 7445 4067 7440
      4061 7443 4061 7433 3973 7467 3970 7514
      4009 7495 4085 7469 4098 7428 4090 7427
TIME...MOT...LOC 2238Z 239DEG 33KT 4086 7448 4034 7465
          3977 7498

$$

GORSE

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 17, 8:54 PM EDT	Rip Current Statement	PHI	Atlantic, Cape May, Monmouth, Ocean	23 hr
Sep 18, 4:13 AM EDT	Coastal Flood Advisory	PHI	Burlington, Camden, Gloucester, Salem	21 hr
Sep 18, 4:21 PM EDT	Severe Thunderstorm Warning	PHI	Salem	69 min
Sep 18, 4:23 PM EDT	Severe Thunderstorm Warning	PHI	Warren	52 min
Sep 18, 4:26 PM EDT	Areal Flood Advisory	PHI	Sussex, Warren	3 hr
Sep 18, 5:01 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Warren	59 min
Sep 18, 5:12 PM EDT	Areal Flood Advisory	PHI	Hunterdon, Morris, Warren	63 min
Sep 18, 5:12 PM EDT	Severe Thunderstorm Warning	PHI	Camden, Gloucester	78 min
Sep 18, 5:13 PM EDT	Severe Thunderstorm Warning	PHI	Morris, Sussex, Warren	62 min
Sep 18, 5:23 PM EDT	Severe Thunderstorm Warning	PHI	Salem	52 min
Sep 18, 6:02 PM EDT	Special Marine Warning	PHI		88 min
Sep 18, 6:06 PM EDT	Areal Flood Advisory	PHI	Burlington, Hunterdon, Mercer, Middlesex, Morris, Somerset and 2 more	54 min
Sep 18, 6:46 PM EDT	Areal Flood Advisory	PHI	Atlantic, Burlington, Camden, Cumberland, Gloucester, Salem	119 min
Sep 18, 6:52 PM EDT	Severe Thunderstorm Warning	PHI	Middlesex, Monmouth, Morris, Somerset	53 min
Sep 18, 6:54 PM EDT	Areal Flood Advisory	PHI	Burlington, Mercer, Middlesex, Monmouth, Morris, Ocean and 1 more	111 min
Sep 18, 7:04 PM EDT	Special Weather Statement	PHI	Atlantic, Burlington, Cumberland	56 min
Sep 18, 7:16 PM EDT	Areal Flood Advisory	PHI	Cape May	59 min
Sep 18, 7:51 PM EDT	Special Weather Statement	PHI	Atlantic, Cape May, Ocean	54 min
Sep 18, 7:52 PM EDT	Special Marine Warning	PHI		77 min
Sep 18, 7:56 PM EDT	Severe Thunderstorm Warning	PHI	Atlantic, Burlington, Cape May, Ocean	64 min
Sep 18, 12:58 PM EDT	Areal Flood Advisory	PHI	Carbon, Monroe	93 min
Sep 18, 12:59 PM EDT	Special Weather Statement	PHI	Berks, Lehigh	46 min
Sep 18, 1:05 PM EDT	Areal Flood Advisory	PHI	Berks, Lehigh	115 min
Sep 18, 1:32 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Lehigh	43 min
Sep 18, 2:00 PM EDT	Special Weather Statement	PHI	Chester, Montgomery	60 min
Sep 18, 2:18 PM EDT	Special Weather Statement	PHI	Carbon, Monroe	57 min
Sep 18, 2:23 PM EDT	Severe Thunderstorm Warning	PHI	Chester, Montgomery	30 min
Sep 18, 2:25 PM EDT	Flash Flood Warning	PHI	Carbon, Lehigh, Monroe, Northampton	4 hr
Sep 18, 2:52 PM EDT	Severe Thunderstorm Warning	PHI	Bucks, Lehigh, Northampton	17 min
Sep 18, 3:07 PM EDT	Areal Flood Warning	PHI	Berks, Lehigh	8 hr
Sep 18, 3:16 PM EDT	Special Weather Statement	PHI	Monroe	59 min
Sep 18, 3:24 PM EDT	Special Weather Statement	PHI	Berks, Carbon	51 min
Sep 18, 3:52 PM EDT	Special Weather Statement	PHI	Chester	53 min
Sep 18, 4:05 PM EDT	Areal Flood Advisory	PHI	Berks, Lehigh	55 min
Sep 18, 4:19 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Chester, Delaware, Montgomery	56 min
Sep 18, 4:35 PM EDT	Areal Flood Advisory	PHI	Bucks, Chester, Lehigh, Montgomery	55 min
Sep 18, 6:19 PM EDT	Areal Flood Warning	PHI	Carbon, Lehigh, Monroe, Northampton	16 hr

Nearby

Severe Thunderstorm Warnings in New Jersey, 2012 Severe Thunderstorm Warnings in Pennsylvania, 2012 Every severe thunderstorm warning in 2012

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.