Alert archive / New Jersey / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 223, NWS Philadelphia/Mount Holly

September 18, 2012Salem County, New Jersey; New Castle County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Sep 18, 2012, 4:21 PM EDT for Salem County, New Jersey; New Castle County, Delaware. It was in force for 69 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: Sep 18, 2012, 4:21 PM EDT (20:21 UTC)
Expired: Sep 18, 2012, 5:30 PM EDT
In force: 69 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon

Counties New Castle County, DE, Salem County, NJ

The radar

The Dover AFB radar (KDOX), 84 km from the middle of the area, began a volume at 20:23 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, 5:30 PM EDT	TSTM WND DMG	Delaware City, DE	SCATTERED REPORTS OF UTILITY WIRES DOWN COUNTYWIDE.

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

Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 8.4 hours before the alert went out and 53 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: 330 J/kg
Mixed-layer CIN: -6 J/kg
Mixed-layer LCL: 519 m above ground
0-6 km bulk shear: 40 kt
0-1 km storm-relative helicity: 265 m²/s²
0-3 km storm-relative helicity: 275 m²/s²
Significant tornado parameter: 0.4
Supercell composite: 2.3

Open this sounding in Storm Lab

The text

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

845 
WUUS51 KPHI 182021
SVRPHI
DEC003-NJC033-182130-
/O.NEW.KPHI.SV.W.0223.120918T2021Z-120918T2130Z/

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

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NEW CASTLE COUNTY IN NORTHERN DELAWARE...
  THIS INCLUDES THE CITIES OF...WILMINGTON...NEWARK...
  SALEM COUNTY IN SOUTHERN NEW JERSEY...

* UNTIL 530 PM EDT

* AT 420 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS
  OF 60 MPH.  THIS STORM WAS LOCATED NEAR DELANEY CORNER...OR 14
  MILES NORTHWEST OF DOVER...AND MOVING NORTHEAST AT 50 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  HOPE CREEK AROUND 435 PM EDT...
  PORT PENN...HANCOCKS BRIDGE AND DELAWARE CITY AROUND 440 PM EDT...
  SALEM AND QUINTON AROUND 445 PM EDT...
  PENNSVILLE AROUND 450 PM EDT...
  CARNEYS POINT...PENNS GROVE AND WOODSTOWN AROUND 455 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.

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...PREPARE 
IMMEDIATELY FOR DAMAGING WINDS...HAIL...AND DEADLY CLOUD TO GROUND 
LIGHTNING. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...PREFERABLY 
INSIDE A STRONG BUILDING BUT 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.

&&

LAT...LON 3981 7569 3984 7560 3984 7549 3979 7541
      3970 7534 3966 7524 3967 7520 3963 7514
      3945 7537 3945 7541 3938 7543 3947 7556
      3950 7556 3946 7558 3942 7553 3936 7551
      3931 7559 3930 7576 3972 7579
TIME...MOT...LOC 2021Z 210DEG 45KT 3932 7569

$$

IOVINO

1 follow-up statement

888 
WWUS51 KPHI 182104
SVSPHI

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

DEC003-NJC033-182130-
/O.CON.KPHI.SV.W.0223.000000T0000Z-120918T2130Z/
NEW CASTLE DE-SALEM NJ-
504 PM EDT TUE SEP 18 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 530 PM EDT
FOR SALEM AND NEW CASTLE COUNTIES...

AT 500 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 HOCKESSIN TO NEAR TOWNSEND...MOVING NORTHEAST AT 45 
MPH.

SEVERE THUNDERSTORMS WILL BE NEAR...
  GREEN SPRING...MOUNT PLEASANT...BEAR AND STANTON BY 510 PM EDT...
  CHAMBERSVILLE...SAINT GEORGES...WILMINGTON MANOR AND TOWNSEND BY
  515 PM EDT...
  WILMINGTON AND ODESSA BY 520 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.

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...PREPARE 
IMMEDIATELY FOR DAMAGING WINDS...HAIL...AND DEADLY CLOUD TO GROUND 
LIGHTNING. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...PREFERABLY 
INSIDE A STRONG BUILDING BUT 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.

&&

LAT...LON 3981 7569 3984 7560 3984 7549 3979 7541
      3970 7534 3966 7524 3967 7520 3963 7514
      3945 7537 3945 7541 3938 7543 3947 7556
      3950 7556 3946 7558 3942 7553 3936 7551
      3931 7559 3930 7576 3972 7579
TIME...MOT...LOC 2103Z 231DEG 46KT 3982 7565 3935 7585

$$

IOVINO

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, 4:23 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, 6:00 PM EDT	Severe Thunderstorm Warning	PHI	Burlington, Camden, Gloucester, Hunterdon, Mercer, Middlesex and 3 more	60 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, 5:57 PM EDT	Severe Thunderstorm Warning	PHI	Kent, Sussex	78 min
Sep 18, 7:08 PM EDT	Severe Thunderstorm Warning	PHI	Sussex	38 min

Nearby

Severe Thunderstorm Warnings in New Jersey, 2012 Severe Thunderstorm Warnings in Delaware, 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.