Alert archive / New Jersey / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 284, NWS Philadelphia/Mount Holly

August 30, 2021Atlantic County, Cape May County, Cumberland County, New Jersey

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 30, 2021, 5:16 PM EDT for Atlantic County, Cape May County, Cumberland County, New Jersey. It was in force for 44 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 30, 2021, 5:16 PM EDT (21:16 UTC)
Expired
Aug 30, 2021, 6:00 PM EDT
In force
44 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

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

The radar

The Dover AFB radar (KDOX), 72 km from the middle of the area, began a volume at 21:20 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 nearest sounding before it

Wallops Is Stn, VA (KWAL), launched 12:00Z, 9.3 hours before the alert went out and 165 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 2021-08-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 392 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 2021-08-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -19 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
392 J/kg
Mixed-layer CIN
-89 J/kg
Mixed-layer LCL
791 m above ground
0-6 km bulk shear
8 kt
0-1 km storm-relative helicity
-19 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.

220 
WUUS51 KPHI 302116
SVRPHI
NJC001-009-011-302200-
/O.NEW.KPHI.SV.W.0284.210830T2116Z-210830T2200Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
516 PM EDT Mon Aug 30 2021

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Southwestern Atlantic County in southern New Jersey...
  Cumberland County in southern New Jersey...
  Northwestern Cape May County in southern New Jersey...

* Until 600 PM EDT.

* At 515 PM EDT, a severe thunderstorm was located over Cedarville,
  or 7 miles south of Bridgeton, moving east at 25 mph.

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

  SOURCE...Radar indicated.

  IMPACT...Damage to roofs, siding, trees, and power lines is 
           possible.

* Locations impacted include...
  Vineland, Millville, Bridgeton, Cumberland, Buena, Laurel Lake,
  Woodbine, Estell Manor, Corbin City, Newport, Leesburg, Dorothy,
  Bricksboro, Fortesque, Mauricetown, Belleplain Forest, Port Norris,
  Dividing Creek, Fairton and Cedarville.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

In addition to 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 3923 7471 3922 7529 3942 7534 3948 7511
      3946 7508 3949 7507 3955 7482
TIME...MOT...LOC 2115Z 276DEG 22KT 3932 7525 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Gorse
3 follow-up statements
018 
WWUS51 KPHI 302127
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
527 PM EDT Mon Aug 30 2021

NJC001-009-011-302200-
/O.CON.KPHI.SV.W.0284.000000T0000Z-210830T2200Z/
Atlantic NJ-Cumberland NJ-Cape May NJ-
527 PM EDT Mon Aug 30 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 600 PM EDT
FOR SOUTHWESTERN ATLANTIC...SOUTHERN CUMBERLAND AND NORTHWESTERN CAPE
MAY COUNTIES...

At 527 PM EDT, a severe thunderstorm was located over Newport, or 8
miles southwest of Millville, moving east at 20 mph.

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

SOURCE...Radar indicated.

IMPACT...Damage to roofs, siding, trees, and power lines is 
         possible.

Locations impacted include...
Vineland, Millville, Cumberland, Laurel Lake, Woodbine, Estell Manor,
Corbin City, Newport, Mauricetown, Belleplain Forest, Leesburg, Port
Norris, Dividing Creek, Dorothy, Bricksboro, Cedarville, Mizpah, Port
Elizabeth, Bivalve and Fortesque.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Frequent cloud to ground lightning is occurring with this storm. Move
indoors immediately. Lightning is one of nature's leading killers.
Remember, if you can hear thunder, you are close enough to be struck
by lightning.

&&

LAT...LON 3923 7471 3922 7529 3934 7531 3950 7480
TIME...MOT...LOC 2127Z 270DEG 19KT 3930 7518 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Gorse
510 
WWUS51 KPHI 302138
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
538 PM EDT Mon Aug 30 2021

NJC001-302148-
/O.CAN.KPHI.SV.W.0284.000000T0000Z-210830T2200Z/
Atlantic NJ-
538 PM EDT Mon Aug 30 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHWESTERN ATLANTIC COUNTY
IS CANCELLED...
    
The severe thunderstorm which prompted the warning has weakened.
Therefore, the warning has been cancelled.

LAT...LON 3923 7471 3922 7529 3934 7531 3943 7499
      3934 7486 3933 7487 3930 7481
TIME...MOT...LOC 2138Z 280DEG 21KT 3928 7511 

$$

NJC009-011-302200-
/O.CON.KPHI.SV.W.0284.000000T0000Z-210830T2200Z/
Cumberland NJ-Cape May NJ-
538 PM EDT Mon Aug 30 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 600 PM EDT
FOR SOUTHERN CUMBERLAND AND NORTHWESTERN CAPE MAY COUNTIES...

At 538 PM EDT, a severe thunderstorm was located over Dividing Creek,
or 8 miles south of Millville, moving east at 25 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Damage to roofs, siding, trees, and power lines is 
         possible.

Locations impacted include...
Vineland, Millville, Cumberland, Laurel Lake, Woodbine, Newport,
Mauricetown, Belleplain Forest, Leesburg, Port Norris, Dividing
Creek, Bricksboro, Cedarville, Port Elizabeth, Bivalve, Fortesque and
Fairton.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Frequent cloud to ground lightning is occurring with this storm. Move
indoors immediately. Lightning is one of nature's leading killers.
Remember, if you can hear thunder, you are close enough to be struck
by lightning.

&&

LAT...LON 3923 7471 3922 7529 3934 7531 3943 7499
      3934 7486 3933 7487 3930 7481
TIME...MOT...LOC 2138Z 280DEG 21KT 3928 7511 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Gorse
803 
WWUS51 KPHI 302150
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
550 PM EDT Mon Aug 30 2021

NJC009-011-302200-
/O.EXP.KPHI.SV.W.0284.000000T0000Z-210830T2200Z/
Cumberland NJ-Cape May NJ-
550 PM EDT Mon Aug 30 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHERN CUMBERLAND AND
NORTHWESTERN CAPE MAY COUNTIES WILL EXPIRE AT 600 PM EDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire.  However gusty
winds and heavy rain are still possible with this thunderstorm.

LAT...LON 3923 7471 3922 7529 3934 7531 3943 7499
      3934 7486 3933 7487 3930 7481
TIME...MOT...LOC 2150Z 276DEG 22KT 3927 7502 

$$

Gorse

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 30, 5:00 AM EDTFlash Flood WatchPHIAtlantic, Burlington, Camden, Cape May, Cumberland, Gloucester and 10 more71 hr
Aug 30, 5:44 AM EDTDense Fog AdvisoryPHIAtlantic, Burlington, Camden, Cape May, Cumberland, Gloucester and 3 more3 hr
Aug 30, 4:48 PM EDTSpecial Weather StatementPHIAtlantic, Cumberland27 min
Aug 30, 5:21 PM EDTSpecial Weather StatementPHIAtlantic24 min
Aug 30, 5:26 PM EDTSpecial Marine WarningPHI64 min
Aug 30, 5:44 PM EDTSpecial Marine WarningPHI61 min
Aug 30, 5:53 PM EDTSpecial Weather StatementPHIAtlantic22 min
Aug 30, 5:56 PM EDTSpecial Weather StatementPHICape May49 min
Aug 30, 6:16 PM EDTSpecial Marine WarningPHI89 min
Aug 30, 6:41 PM EDTSpecial Weather StatementPHICape May34 min
Aug 30, 7:20 PM EDTSpecial Weather StatementPHICape May25 min
Aug 30, 7:31 PM EDTSpecial Marine WarningPHI59 min

Nearby

Severe Thunderstorm Warnings in New Jersey, 2021Every severe thunderstorm warning in 2021

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.