Alert archive / New Jersey / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 13, NWS Philadelphia/Mount Holly

April 21, 20214 counties in New Jersey

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Apr 21, 2021, 1:28 PM EDT for 4 counties in New Jersey. It was in force for 36 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: Apr 21, 2021, 1:28 PM EDT (17:28 UTC)
Expired: Apr 21, 2021, 2:04 PM EDT
In force: 36 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Atlantic County, NJ, Burlington County, NJ, Camden County, NJ, Gloucester County, NJ

The radar

The Philadelphia radar (KDIX), 44 km from the middle of the area, began a volume at 17:27 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
Apr 21, 1:48 PM EDT	HAIL 0.88	Medford, NJ	MOSTLY PEA-SIZED WITH A FEW PENNY TO NICKEL-SIZED STONES. REPORT VIA SOCIAL MEDIA.

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
Apr 21, 12:28 PM EDT	Severe Thunderstorm Watch	SPC	5 hr

The nearest sounding before it

Wallops Is Stn, VA (KWAL), launched 12:00Z, 5.5 hours before the alert went out and 209 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: 12 J/kg
Mixed-layer CIN: -142 J/kg
Mixed-layer LCL: 1437 m above ground
0-6 km bulk shear: 35 kt
0-1 km storm-relative helicity: 136 m²/s²
0-3 km storm-relative helicity: 126 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

040 
WUUS51 KPHI 211728
SVRPHI
NJC001-005-007-015-211815-
/O.NEW.KPHI.SV.W.0013.210421T1728Z-210421T1815Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
128 PM EDT Wed Apr 21 2021

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Northwestern Atlantic County in southern New Jersey...
  Camden County in southern New Jersey...
  East central Gloucester County in southern New Jersey...
  Central Burlington County in southern New Jersey...

* Until 215 PM EDT.

* At 128 PM EDT, a severe thunderstorm was located over Marlton
  Lakes, or 13 miles southeast of Gloucester City, moving northeast
  at 55 mph.

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

  SOURCE...Radar indicated.

  IMPACT...Minor damage to vehicles is possible. Wind damage to 
           roofs, siding, trees, and power lines is possible.

* Locations impacted include...
  Evesham, Voorhees, Medford, Lindenwold, Hammonton, Lumberton, Mount
  Holly, Clayton, Berlin, Tabernacle, Shamong, Magnolia, Chesilhurst,
  Pemberton, Wrightstown, Atsion, Marlton, Leisuretowne, Georgetown
  and Victory Lakes.

This includes the following highways...
 Interstate 295 in New Jersey near mile marker 32.
 Atlantic City Expressway between mile markers 30 and 44.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Protecting yourself from immediate threats to life and safety shall
take priority.  Whenever possible, as long as it does not cause
greater harm, all COVID-19 protective action guidance should be
followed.

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

&&

LAT...LON 3960 7505 3984 7508 4011 7462 3967 7456
TIME...MOT...LOC 1728Z 241DEG 48KT 3979 7490 

HAIL...1.00IN
WIND...60MPH
 
$$

Davis

3 follow-up statements

816 
WWUS51 KPHI 211746
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
146 PM EDT Wed Apr 21 2021

NJC001-015-211755-
/O.CAN.KPHI.SV.W.0013.000000T0000Z-210421T1815Z/
Atlantic NJ-Gloucester NJ-
146 PM EDT Wed Apr 21 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN ATLANTIC AND EAST
CENTRAL GLOUCESTER COUNTIES IS CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

A Severe Thunderstorm Watch remains in effect until 600 PM EDT for
southern New Jersey.

LAT...LON 3974 7484 3989 7497 4011 7462 3980 7459
TIME...MOT...LOC 1745Z 241DEG 48KT 3991 7463 

$$

NJC005-007-211815-
/O.CON.KPHI.SV.W.0013.000000T0000Z-210421T1815Z/
Camden NJ-Burlington NJ-
146 PM EDT Wed Apr 21 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 215 PM EDT
FOR EAST CENTRAL CAMDEN AND CENTRAL BURLINGTON COUNTIES...

At 145 PM EDT, a severe thunderstorm was located near Presidential
Lakes, or 23 miles south of Trenton, moving northeast at 55 mph.

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

SOURCE...Radar indicated.

IMPACT...Minor damage to vehicles is possible. Wind damage to roofs, 
         siding, trees, and power lines is possible.

Locations impacted include...
Evesham, Medford, Lumberton, Mount Holly, Tabernacle, Shamong,
Pemberton, Wrightstown, Jobstown, Marlton, Leisuretowne, Marlton
Lakes, Georgetown, Greentree, Springdale, Medford Lakes, Pemberton
Heights and Fort Dix.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Protecting yourself from immediate threats to life and safety shall
take priority.  Whenever possible, as long as it does not cause
greater harm, all COVID-19 protective action guidance should be
followed.

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 3974 7484 3989 7497 4011 7462 3980 7459
TIME...MOT...LOC 1745Z 241DEG 48KT 3991 7463 

HAIL...1.00IN
WIND...60MPH
 
$$

Davis

303 
WWUS51 KPHI 211756
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
156 PM EDT Wed Apr 21 2021

NJC007-211805-
/O.CAN.KPHI.SV.W.0013.000000T0000Z-210421T1815Z/
Camden NJ-
156 PM EDT Wed Apr 21 2021

...THE SEVERE THUNDERSTORM WARNING FOR EAST CENTRAL CAMDEN COUNTY IS
CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

A Severe Thunderstorm Watch remains in effect until 600 PM EDT for
southern New Jersey.

LAT...LON 3977 7475 3998 7482 4011 7462 3980 7459
TIME...MOT...LOC 1755Z 241DEG 48KT 3998 7447 

$$

NJC005-211815-
/O.CON.KPHI.SV.W.0013.000000T0000Z-210421T1815Z/
Burlington NJ-
156 PM EDT Wed Apr 21 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 215 PM EDT
FOR CENTRAL BURLINGTON COUNTY...

At 155 PM EDT, a severe thunderstorm was located near Cedar Glen
Lakes, or 15 miles west of Toms River, moving northeast at 55 mph.

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

SOURCE...Trained weather spotters.

IMPACT...Minor damage to vehicles is possible. Wind damage to roofs, 
         siding, trees, and power lines is possible.

Locations impacted include...
Lumberton, Mount Holly, Tabernacle, Pemberton, Wrightstown, Jobstown,
Leisuretowne, Georgetown, Pemberton Heights and Fort Dix.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Protecting yourself from immediate threats to life and safety shall
take priority.  Whenever possible, as long as it does not cause
greater harm, all COVID-19 protective action guidance should be
followed.

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

&&

LAT...LON 3977 7475 3998 7482 4011 7462 3980 7459
TIME...MOT...LOC 1755Z 241DEG 48KT 3998 7447 

HAIL...1.00IN
WIND...60MPH
 
$$

Davis

917 
WWUS51 KPHI 211804
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
204 PM EDT Wed Apr 21 2021

NJC005-211814-
/O.CAN.KPHI.SV.W.0013.000000T0000Z-210421T1815Z/
Burlington NJ-
204 PM EDT Wed Apr 21 2021

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL BURLINGTON COUNTY IS
CANCELLED...
        
The storm which prompted the warning has moved out of the area.
Therefore, the warning has been cancelled.  However small hail and
gusty winds are still possible with this thunderstorm.

A Severe Thunderstorm Watch remains in effect until 600 PM EDT for
southern New Jersey.

LAT...LON 3977 7475 3998 7482 4011 7462 3980 7459
TIME...MOT...LOC 1801Z 241DEG 48KT 4004 7433 

$$

Davis

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 20, 8:48 PM EDT	Freeze Watch	PHI	Hunterdon, Morris, Somerset, Sussex, Warren	7 hr
Apr 21, 3:26 AM EDT	Freeze Warning	PHI	Hunterdon, Morris, Somerset, Sussex, Warren	30 hr
Apr 21, 12:25 PM EDT	Severe Thunderstorm Warning	PHI	Warren	50 min
Apr 21, 12:51 PM EDT	Severe Thunderstorm Warning	PHI	Sussex, Warren	21 min
Apr 21, 12:55 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Warren	27 min
Apr 21, 1:10 PM EDT	Severe Thunderstorm Warning	PHI	Burlington, Camden, Gloucester, Mercer, Salem	50 min
Apr 21, 1:17 PM EDT	Special Weather Statement	PHI	Hunterdon, Morris, Somerset, Sussex	58 min
Apr 21, 1:30 PM EDT	Special Marine Warning	PHI		60 min
Apr 21, 1:43 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Middlesex, Morris, Somerset	33 min
Apr 21, 1:58 PM EDT	Special Weather Statement	PHI	Burlington, Camden, Monmouth, Ocean	62 min
Apr 21, 2:02 PM EDT	Severe Thunderstorm Warning	PHI	Burlington, Camden, Monmouth, Ocean	43 min
Apr 21, 2:03 PM EDT	Special Weather Statement	PHI	Cumberland	27 min
Apr 21, 2:17 PM EDT	Severe Thunderstorm Warning	PHI	Atlantic, Cumberland, Gloucester, Salem	43 min
Apr 21, 2:28 PM EDT	Special Weather Statement	PHI	Middlesex, Monmouth	47 min
Apr 21, 2:30 PM EDT	Special Marine Warning	PHI		60 min
Apr 21, 2:38 PM EDT	Severe Thunderstorm Warning	PHI	Monmouth, Ocean	37 min
Apr 21, 2:40 PM EDT	Special Marine Warning	PHI		55 min
Apr 21, 2:43 PM EDT	Special Weather Statement	PHI	Cape May	32 min
Apr 21, 2:50 PM EDT	Severe Thunderstorm Warning	PHI	Atlantic, Burlington, Ocean	40 min
Apr 21, 3:02 PM EDT	Severe Thunderstorm Warning	PHI	Atlantic	28 min
Apr 21, 3:07 PM EDT	Special Marine Warning	PHI		53 min

Nearby

Severe Thunderstorm Warnings in New Jersey, 2021 Every 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.