Alert archive / New Jersey / Severe Thunderstorm Warnings in 2009

Severe Thunderstorm Warning 168, NWS Philadelphia/Mount Holly

July 31, 20098 counties in New Jersey

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 31, 2009, 4:39 PM EDT for 8 counties in New Jersey. It was in force for 96 min. 3 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
Jul 31, 2009, 4:39 PM EDT (20:39 UTC)
Expired
Jul 31, 2009, 6:15 PM EDT
In force
96 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon

Counties Atlantic County, NJ, Burlington County, NJ, Camden County, NJ, Cape May County, NJ, Cumberland County, NJ, Gloucester County, NJ, Ocean County, NJ, Salem County, NJ

The radar

The Dover AFB radar (KDOX), 70 km from the middle of the area, began a volume at 20:39 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
Jul 31, 5:03 PM EDTTSTM WND GST 58Newport, NJMEASURED GUST OF 58 MPH IN NEWPORT.
Jul 31, 5:05 PM EDTTSTM WND GST 60Newport, NJESTIMATED GUST OF 50 TO 60 MPH IN NEWPORT.
Jul 31, 5:50 PM EDTTSTM WND GST 55Mays Landing, NJWIND GUSTS ESTIMATED BETWEEN 45 AND 55 MPH IN MAYS LANDING AND SOMERS POINT.

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
Jul 31, 1:18 PM EDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Wallops Is Stn, VA (KWAL), launched 12:00Z, 8.7 hours before the alert went out and 154 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 12:00Z on 2009-07-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 969 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 12:00Z on 2009-07-31The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 53 square meters per square second.193958Sfc1 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
969 J/kg
Mixed-layer CIN
-11 J/kg
Mixed-layer LCL
484 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
53 m²/s²
0-3 km storm-relative helicity
101 m²/s²
Significant tornado parameter
0.3
Supercell composite
2.0

Open this sounding in Storm Lab

The text

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

000 
WUUS51 KPHI 312039
SVRPHI
NJC001-005-007-009-011-015-029-033-312215-
/O.NEW.KPHI.SV.W.0168.090731T2039Z-090731T2215Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
439 PM EDT FRI JUL 31 2009

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  ATLANTIC COUNTY IN SOUTHERN NEW JERSEY...
  THIS INCLUDES THE CITY OF ATLANTIC CITY...
  SOUTHEASTERN BURLINGTON COUNTY IN SOUTHERN NEW JERSEY...
  SOUTHEASTERN CAMDEN COUNTY IN SOUTHERN NEW JERSEY...
  CAPE MAY COUNTY IN SOUTHERN NEW JERSEY...
  THIS INCLUDES THE CITY OF CAPE MAY...
  CUMBERLAND COUNTY IN SOUTHERN NEW JERSEY...
  THIS INCLUDES THE CITIES OF...VINELAND...MILLVILLE...
  SOUTHEASTERN GLOUCESTER COUNTY IN SOUTHERN NEW JERSEY...
  EXTREME SOUTHWESTERN OCEAN COUNTY IN SOUTHERN NEW JERSEY...
  SOUTHERN SALEM COUNTY IN SOUTHERN NEW JERSEY...

* UNTIL 615 PM EDT

* AT 435 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 16 MILES WEST OF ALLOWAY TO 31 MILES SOUTHWEST OF GREENWICH...
  OR ALONG A LINE EXTENDING FROM 6 MILES NORTHEAST OF MIDDLETOWN TO
  13 MILES SOUTHWEST OF DOVER...AND MOVING EAST AT 45 MPH.

* SEVERE THUNDERSTORMS WILL BE NEAR...
  GREENWICH AND ALLOWAY AROUND 455 PM EDT...
  SHILOH AROUND 500 PM EDT...
  CEDARVILLE...SEABROOK FARMS...FAIRTON AND BRIDGETON AROUND 505 PM
  EDT...
  NEWPORT...ROSENHAYN AND OLIVET AROUND 510 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 900 PM EDT FRIDAY
EVENING FOR DELAWARE AND NORTHEASTERN MARYLAND AND NEW JERSEY AND
EASTERN PENNSYLVANIA.

&&

LAT...LON 3937 7442 3930 7455 3907 7474 3893 7490
      3901 7497 3911 7490 3916 7491 3918 7503
      3920 7505 3918 7513 3953 7553 3976 7439
TIME...MOT...LOC 2038Z 255DEG 39KT 3952 7559 3901 7561

$$

AMC
2 follow-up statements
000 
WWUS51 KPHI 312144
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
544 PM EDT FRI JUL 31 2009

NJC007-011-015-033-312154-
/O.CAN.KPHI.SV.W.0168.000000T0000Z-090731T2215Z/
SALEM NJ-CUMBERLAND NJ-CAMDEN NJ-GLOUCESTER NJ-
544 PM EDT FRI JUL 31 2009

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN GLOUCESTER...
SOUTHEASTERN CAMDEN...CUMBERLAND AND SOUTHERN SALEM COUNTIES IS
CANCELLED...

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 PM EDT FRIDAY
EVENING FOR DELAWARE AND NORTHEASTERN MARYLAND AND NEW JERSEY AND
EASTERN PENNSYLVANIA.

LAT...LON 3969 7474 3976 7439 3937 7442 3930 7455
      3907 7474 3893 7490 3901 7497 3911 7490
      3916 7491
TIME...MOT...LOC 2144Z 257DEG 47KT 3971 7461 3951 7461
          3920 7463

$$

NJC001-005-009-029-312215-
/O.CON.KPHI.SV.W.0168.000000T0000Z-090731T2215Z/
CAPE MAY NJ-OCEAN NJ-ATLANTIC NJ-BURLINGTON NJ-
544 PM EDT FRI JUL 31 2009

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 615 PM EDT
FOR SOUTHEASTERN BURLINGTON...ATLANTIC...EXTREME SOUTHWESTERN OCEAN
AND CAPE MAY COUNTIES...

AT 542 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 BATSTO TO EGG HARBOR CITY TO SEAVILLE...OR ALONG A
LINE EXTENDING FROM 25 MILES NORTHEAST OF VINELAND TO 14 MILES
NORTHWEST OF ATLANTIC CITY TO 17 MILES SOUTHWEST OF ATLANTIC CITY...
MOVING EAST AT 55 MPH.

SEVERE THUNDERSTORMS WILL BE NEAR...
  WADING RIVER...PORT REPUBLIC...POMONA AND PLEASANTVILLE BY 550 PM
  EDT...
  PENN STATE FOREST...NEW GRETNA...BASS RIVER STATE FOREST AND
  VENTNOR CITY BY 555 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 PM EDT FRIDAY
EVENING FOR DELAWARE AND NORTHEASTERN MARYLAND AND NEW JERSEY AND
EASTERN PENNSYLVANIA.

&&

LAT...LON 3969 7474 3976 7439 3937 7442 3930 7455
      3907 7474 3893 7490 3901 7497 3911 7490
      3916 7491
TIME...MOT...LOC 2144Z 257DEG 47KT 3971 7461 3951 7461
          3920 7463

$$

AMC
000 
WWUS51 KPHI 312217
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
617 PM EDT FRI JUL 31 2009

NJC001-005-009-029-312226-
/O.EXP.KPHI.SV.W.0168.000000T0000Z-090731T2215Z/
CAPE MAY NJ-OCEAN NJ-ATLANTIC NJ-BURLINGTON NJ-
617 PM EDT FRI JUL 31 2009

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN BURLINGTON...
ATLANTIC...EXTREME SOUTHWESTERN OCEAN AND CAPE MAY COUNTIES HAS
EXPIRED...

THE STORMS WHICH PROMPTED THE WARNING HAVE MOVED EAST OF THE AREA 
AND ARE NO LONGER A THREAT.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 PM EDT FRIDAY
EVENING FOR SOUTHERN DELAWARE AND EASTERN MARYLAND AND NEW JERSEY AND
SOUTHEAST PENNSYLVANIA.

LAT...LON 3969 7474 3976 7439 3937 7442 3930 7455
      3907 7474 3893 7490 3901 7497 3911 7490
      3916 7491
TIME...MOT...LOC 2144Z 257DEG 47KT 3971 7461 3951 7461
          3920 7463

$$

AMC

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 31, 2:13 PM EDTFlash Flood WarningPHISussex4 hr
Jul 31, 2:36 PM EDTFlash Flood WarningPHIHunterdon, Morris, Sussex, Warren4 hr
Jul 31, 4:03 PM EDTSevere Thunderstorm WarningPHIGloucester, Salem57 min
Jul 31, 4:08 PM EDTFlash Flood WarningPHIBurlington, Camden, Gloucester, Salem3 hr
Jul 31, 4:23 PM EDTSpecial Marine WarningPHI67 min
Jul 31, 4:31 PM EDTSevere Thunderstorm WarningPHIAtlantic, Burlington, Camden, Gloucester, Salem59 min
Jul 31, 4:56 PM EDTFlash Flood WarningPHIHunterdon, Mercer, Middlesex, Monmouth, Morris, Somerset114 min
Jul 31, 5:07 PM EDTFlash Flood WarningPHIAtlantic, Burlington, Camden, Cumberland, Gloucester, Salem3 hr
Jul 31, 5:10 PM EDTTornado WarningPHIBurlington, Ocean21 min
Jul 31, 5:14 PM EDTSpecial Marine WarningPHI2 hr
Jul 31, 5:15 PM EDTSevere Thunderstorm WarningPHIAtlantic, Ocean60 min
Jul 31, 5:16 PM EDTSpecial Marine WarningPHI119 min
Jul 31, 5:31 PM EDTFlash Flood WarningPHIBurlington, Monmouth, Ocean4 hr
Jul 31, 5:48 PM EDTAreal Flood AdvisoryPHIAtlantic, Burlington, Cape May, Cumberland, Ocean3 hr

Nearby

Severe Thunderstorm Warnings in New Jersey, 2009Every severe thunderstorm warning in 2009

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.