Alert archive / New Jersey / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 174, NWS Philadelphia/Mount Holly

August 18, 20174 counties in New Jersey

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 18, 2017, 7:49 PM EDT for 4 counties in New Jersey. It was in force for 35 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 18, 2017, 7:49 PM EDT (23:49 UTC)
Expired
Aug 18, 2017, 8:24 PM EDT
In force
35 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Tornado
Possible
Hail
0.88 in
Wind
60.0 mph

Counties Atlantic County, NJ, Cape May County, NJ, Cumberland County, NJ, Gloucester County, NJ

The radar

The Dover AFB radar (KDOX), 72 km from the middle of the area, began a volume at 23:52 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.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Aug 18, 2:27 PM EDTSevere Thunderstorm WatchSPC9 hr

The nearest sounding before it

Wallops Is Stn, VA (KWAL), launched 12:00Z, 11.8 hours before the alert went out and 155 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 2017-08-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 582 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, Wallops Is Stn, VA at 12:00Z on 2017-08-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 105 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
582 J/kg
Mixed-layer CIN
-57 J/kg
Mixed-layer LCL
808 m above ground
0-6 km bulk shear
19 kt
0-1 km storm-relative helicity
105 m²/s²
0-3 km storm-relative helicity
112 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

213 
WUUS51 KPHI 182349
SVRPHI
NJC001-009-011-015-190045-
/O.NEW.KPHI.SV.W.0174.170818T2349Z-170819T0045Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
749 PM EDT FRI AUG 18 2017

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Atlantic County in southern New Jersey...
  Eastern Cumberland County in southern New Jersey...
  Southeastern Gloucester County in southern New Jersey...
  Cape May County in southern New Jersey...

* Until 845 PM EDT

* At 749 PM EDT, severe thunderstorms were located along a line
  extending from Buena to near Bivalve, moving east at 20 mph.

  HAZARD...60 mph wind gusts and nickel size hail. 

  SOURCE...Radar indicated. 

  IMPACT...Expect damage to trees and power lines. 

* Locations impacted include...
  Vineland, Atlantic City, Millville, Ocean City, Cumberland,
  Pleasantville, Somers Point, Ventnor City, Brigantine, Northfield,
  Absecon, Margate City, Buena, Egg Harbor City, North Wildwood,
  Laurel Lake, Weymouth, Woodbine, Sea Isle City and Estell Manor.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain alert for a possible tornado! Tornadoes can develop quickly
from severe thunderstorms. If you spot a tornado go at once into the
basement or small central room in a sturdy structure.

In addition to large hail and damaging winds...frequent cloud to
ground lightning is occurring with this storm. Move indoors
immediately. Remember...if you can hear thunder...you are close
enough to be struck by lightning.

&&

LAT...LON 3931 7444 3919 7462 3901 7478 3908 7495
      3915 7493 3919 7508 3916 7514 3917 7517
      3961 7500 3950 7437
TIME...MOT...LOC 2349Z 290DEG 18KT 3952 7496 3922 7507 

TORNADO...POSSIBLE
HAIL...0.88IN
WIND...60MPH
 
$$

SFJ
2 follow-up statements
566 
WWUS51 KPHI 190011
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
811 PM EDT FRI AUG 18 2017

NJC015-190021-
/O.CAN.KPHI.SV.W.0174.000000T0000Z-170819T0045Z/
Gloucester NJ-
811 PM EDT FRI AUG 18 2017

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

The storms which prompted the warning have moved out of the county. 
Therefore, the warning has been cancelled.

A severe thunderstorm watch remains in effect until 900 PM EDT for
southern New Jersey.

LAT...LON 3932 7444 3919 7462 3901 7478 3908 7495
      3915 7493 3919 7508 3959 7489 3950 7437
TIME...MOT...LOC 0011Z 290DEG 18KT 3949 7484 3919 7495 

$$

NJC001-009-011-190045-
/O.CON.KPHI.SV.W.0174.000000T0000Z-170819T0045Z/
Atlantic NJ-Cumberland NJ-Cape May NJ-
811 PM EDT FRI AUG 18 2017

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 845 PM EDT
FOR ATLANTIC...SOUTHEASTERN CUMBERLAND AND CAPE MAY COUNTIES...

At 811 PM EDT, severe thunderstorms were located along a line
extending from Mizpah to near Eldora, moving east at 20 mph.

HAZARD...60 mph wind gusts and penny size hail. 

SOURCE...Radar indicated. 

IMPACT...Expect damage to trees and power lines. 

Locations impacted include...
Vineland, Atlantic City, Millville, Ocean City, Cumberland,
Pleasantville, Somers Point, Ventnor City, Brigantine, Northfield,
Absecon, Margate City, Buena, Egg Harbor City, North Wildwood, Laurel
Lake, Weymouth, Woodbine, Sea Isle City and Estell Manor.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain alert for a possible tornado! Tornadoes can develop quickly
from severe thunderstorms. If you spot a tornado go at once into the
basement or small central room in a sturdy structure.

&&

LAT...LON 3932 7444 3919 7462 3901 7478 3908 7495
      3915 7493 3919 7508 3959 7489 3950 7437
TIME...MOT...LOC 0011Z 290DEG 18KT 3949 7484 3919 7495 

TORNADO...POSSIBLE
HAIL...0.75IN
WIND...60MPH
 
$$

SFJ
319 
WWUS51 KPHI 190024
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
824 PM EDT FRI AUG 18 2017

NJC001-009-011-190034-
/O.CAN.KPHI.SV.W.0174.000000T0000Z-170819T0045Z/
Atlantic NJ-Cumberland NJ-Cape May NJ-
824 PM EDT FRI AUG 18 2017

...THE SEVERE THUNDERSTORM WARNING FOR ATLANTIC...SOUTHEASTERN
CUMBERLAND AND CAPE MAY COUNTIES IS CANCELLED...
            
The storms which prompted the warning have weakened below severe
limits, and no longer pose an immediate threat to life or property.
Therefore the warning has been cancelled.  However gusty winds are
still possible with these thunderstorms.

A severe thunderstorm watch remains in effect until 1100 PM EDT for
southern New Jersey.

LAT...LON 3932 7444 3919 7462 3901 7478 3908 7495
      3915 7493 3919 7508 3959 7489 3950 7437
TIME...MOT...LOC 0021Z 290DEG 18KT 3947 7477 3917 7488 

$$

SFJ

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 18, 3:39 AM EDTFlash Flood WatchPHIAtlantic, Burlington, Camden, Cape May, Cumberland, Gloucester and 10 more18 hr
Aug 18, 3:41 AM EDTSmall Craft AdvisoryPHI18 hr
Aug 18, 10:51 AM EDTSpecial Weather StatementPHIOcean54 min
Aug 18, 11:19 AM EDTAreal Flood AdvisoryPHIBurlington, Ocean116 min
Aug 18, 11:28 AM EDTSpecial Weather StatementPHIOcean47 min
Aug 18, 5:08 PM EDTSpecial Weather StatementPHIHunterdon, Warren37 min
Aug 18, 5:11 PM EDTSevere Thunderstorm WarningPHIHunterdon, Mercer, Somerset49 min
Aug 18, 5:20 PM EDTAreal Flood AdvisoryPHIBurlington, Camden, Gloucester, Mercer, Salem3 hr
Aug 18, 5:39 PM EDTSevere Thunderstorm WarningPHIBurlington, Camden, Gloucester, Salem66 min
Aug 18, 5:42 PM EDTSpecial Weather StatementPHIHunterdon33 min
Aug 18, 5:46 PM EDTSevere Thunderstorm WarningPHIHunterdon, Morris, Somerset44 min
Aug 18, 5:50 PM EDTSpecial Marine WarningPHI55 min
Aug 18, 5:54 PM EDTSevere Thunderstorm WarningPHIBurlington, Mercer, Middlesex, Monmouth66 min
Aug 18, 6:13 PM EDTSpecial Weather StatementPHIMiddlesex, Somerset32 min
Aug 18, 6:20 PM EDTAreal Flood AdvisoryPHIMiddlesex, Somerset3 hr
Aug 18, 6:23 PM EDTSpecial Weather StatementPHISomerset37 min
Aug 18, 6:38 PM EDTSpecial Weather StatementPHICamden, Gloucester, Salem37 min
Aug 18, 6:41 PM EDTSpecial Marine WarningPHI64 min
Aug 18, 6:43 PM EDTAreal Flood AdvisoryPHIMonmouth, Ocean3 hr
Aug 18, 6:48 PM EDTSpecial Weather StatementPHICumberland, Gloucester, Salem27 min
Aug 18, 6:53 PM EDTSpecial Weather StatementPHIMiddlesex, Monmouth52 min
Aug 18, 6:54 PM EDTSpecial Weather StatementPHIBurlington, Camden, Gloucester51 min
Aug 18, 6:58 PM EDTSevere Thunderstorm WarningPHIBurlington, Camden, Ocean29 min
Aug 18, 7:00 PM EDTSevere Thunderstorm WarningPHIBurlington, Mercer, Middlesex, Monmouth, Ocean60 min
Aug 18, 7:19 PM EDTAreal Flood AdvisoryPHIAtlantic, Burlington, Cape May, Cumberland, Ocean, Salem3 hr
Aug 18, 7:25 PM EDTSpecial Weather StatementPHIAtlantic50 min
Aug 18, 7:34 PM EDTSpecial Weather StatementPHICape May26 min
Aug 18, 7:39 PM EDTSpecial Marine WarningPHI66 min
Aug 18, 7:43 PM EDTSpecial Weather StatementPHIBurlington, Ocean47 min
Aug 18, 7:44 PM EDTSpecial Marine WarningPHI61 min

Nearby

Severe Thunderstorm Warnings in New Jersey, 2017Every severe thunderstorm warning in 2017

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.