Alert archive / New Jersey / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 200, NWS Philadelphia/Mount Holly

July 17, 20215 counties in New Jersey; Bucks County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 17, 2021, 10:21 PM EDT for 5 counties in New Jersey; Bucks County, Pennsylvania. It was in force for 54 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 17, 2021, 10:21 PM EDT (02:21 UTC)
Expired: Jul 17, 2021, 11:15 PM EDT
In force: 54 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Tornado: Possible
Hail: 1.0 in
Wind: 60.0 mph

Counties Burlington County, NJ, Mercer County, NJ, Middlesex County, NJ, Monmouth County, NJ, Ocean County, NJ, Bucks County, PA

The radar

The Philadelphia radar (KDIX), 23 km from the middle of the area, began a volume at 02:20 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.

What was reported inside it

Time	Report	Where	Remark
Jul 17, 10:25 PM EDT	TORNADO	2 Nw Jobstown, NJ	NWS STORM SURVEY CONFIRMED A TORNADO BEGAN AT 10:25 PM EDT JUST EAST OF THE ROUTE 206 AND COLUMBUS-JOBSTOWN ROAD INTERSECTION. A NARROW, DISCONTINUOUS, PATH OF TREE DAMAGE CONTINUED FOR 7.9 MILES, ENDING NEAR JACOBSTOWN, NJ. THE TORNADO DISSIPATED AROUND 10:36
Jul 17, 10:26 PM EDT	TSTM WND DMG	2 Nw Jobstown, NJ	SEVERAL TREES UPROOTED AND ROADS BLOCKED IN A NEIGHBORHOOD IN SOUTH COLUMBUS. TIME ESTIMATED FROM RADAR.
Jul 17, 10:32 PM EDT	TSTM WND DMG	3 Ssw Chesterfield, NJ	LARGE TREE SNAPPED AND SEVERAL LARGE LIMBS DOWN. TIME ESTIMATED FROM RADAR.

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
Jul 17, 1:13 PM EDT	Severe Thunderstorm Watch	SPC	10 hr

The nearest sounding before it

Brookhaven, NY (KOKX), launched 00:00Z, 2.4 hours before the alert went out and 158 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: 1431 J/kg
Mixed-layer CIN: -48 J/kg
Mixed-layer LCL: 988 m above ground
0-6 km bulk shear: 23 kt
0-1 km storm-relative helicity: 26 m²/s²
0-3 km storm-relative helicity: 54 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.6

Open this sounding in Storm Lab

The text

As transmitted.

312 
WUUS51 KPHI 180221
SVRPHI
NJC005-021-023-025-029-PAC017-180315-
/O.NEW.KPHI.SV.W.0200.210718T0221Z-210718T0315Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
1021 PM EDT Sat Jul 17 2021

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Northwestern Ocean County in southern New Jersey...
  Mercer County in central New Jersey...
  Northeastern Burlington County in southern New Jersey...
  Central Monmouth County in central New Jersey...
  Southern Middlesex County in northern New Jersey...
  Southeastern Bucks County in southeastern Pennsylvania...

* Until 1115 PM EDT.

* At 1021 PM EDT, severe thunderstorms were located along a line
  extending from Woodside to Bristol to Lumberton, moving east at 35
  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...
  Toms River, Trenton, Lakewood, Old Bridge, Jackson, Howell, East
  Brunswick, Marlboro, Manalapan, Ewing, Willingboro, Medford,
  Holmdel, Lumberton, Princeton, Florence, Burlington, Bristol, Mount
  Holly and Matawan.

This includes the following highways...
 New Jersey Turnpike between exits 5 and 9.
 Pennsylvania Turnpike between mile markers 354 and 359.
 Interstate 95 in Pennsylvania between mile markers 37 and 40.
 Interstate 195 in New Jersey between mile markers 0 and 31.
 Interstate 295 in New Jersey between mile markers 43 and 76.
 Garden State Parkway between mile markers 118 and 122.

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.

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

Torrential rainfall is occurring with these storms, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3986 7429 3989 7483 4011 7494 4029 7489
      4046 7425 4045 7421 4022 7413
TIME...MOT...LOC 0221Z 266DEG 32KT 4022 7485 4012 7488 3998 7481 

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

Staarmann

3 follow-up statements

445 
WWUS51 KPHI 180238
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
1038 PM EDT Sat Jul 17 2021

NJC005-021-023-025-029-PAC017-180315-
/O.CON.KPHI.SV.W.0200.000000T0000Z-210718T0315Z/
Ocean NJ-Mercer NJ-Burlington NJ-Monmouth NJ-Middlesex NJ-Bucks PA-
1038 PM EDT Sat Jul 17 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1115 PM EDT
FOR NORTHWESTERN OCEAN...MERCER...NORTHEASTERN BURLINGTON...CENTRAL
MONMOUTH...SOUTHERN MIDDLESEX AND SOUTHEASTERN BUCKS COUNTIES...

At 1038 PM EDT, severe thunderstorms were located along a line
extending from Mercerville-Hamilton Square to near Cream Ridge to
Pemberton, moving east at 45 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...
Toms River, Trenton, Lakewood, Old Bridge, Jackson, Howell, East
Brunswick, Marlboro, Manalapan, Ewing, Medford, Holmdel, Lumberton,
Princeton, Florence, Burlington, Bristol, Mount Holly, Matawan and
Jamesburg.

This includes the following highways...
 New Jersey Turnpike between exits 5 and 9.
 Pennsylvania Turnpike between mile markers 358 and 359.
 Interstate 195 in New Jersey between mile markers 0 and 31.
 Interstate 295 in New Jersey between mile markers 47 and 75.
 Garden State Parkway between mile markers 118 and 122.

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.

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

Torrential rainfall is occurring with these storms, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3986 7429 3989 7483 4011 7485 4031 7483
      4046 7425 4045 7421 4022 7413
TIME...MOT...LOC 0238Z 269DEG 38KT 4025 7469 4010 7457 3998 7469 

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

Staarmann

523 
WWUS51 KPHI 180249 RRA
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
1049 PM EDT Sat Jul 17 2021

PAC017-180258-
/O.CAN.KPHI.SV.W.0200.000000T0000Z-210718T0315Z/
Bucks PA-
1049 PM EDT Sat Jul 17 2021

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

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

A Severe Thunderstorm Watch remains in effect until 1100 PM EDT for
southern, central and northern New Jersey.

LAT...LON 3989 7479 4011 7468 4033 7475 4046 7425
      4045 7421 4022 7413 3986 7429
TIME...MOT...LOC 0248Z 264DEG 33KT 4028 7458 4012 7444 3991 7458 

$$

NJC005-021-023-025-029-180315-
/O.CON.KPHI.SV.W.0200.000000T0000Z-210718T0315Z/
Ocean NJ-Mercer NJ-Burlington NJ-Monmouth NJ-Middlesex NJ-
1049 PM EDT Sat Jul 17 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1115 PM EDT
FOR NORTHWESTERN OCEAN...EASTERN MERCER...NORTHEASTERN BURLINGTON...
CENTRAL MONMOUTH AND SOUTHERN MIDDLESEX COUNTIES...

At 1048 PM EDT, severe thunderstorms were located along a line
extending from near Edinburg to Six Flags Theme Park to Presidential
Lakes Estates, moving east at 40 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...
Toms River, Lakewood, Old Bridge, Jackson, Howell, East Brunswick,
Marlboro, Manalapan, Holmdel, Princeton, Matawan, Jamesburg,
Hightstown, Cranbury, Presidential Lakes Estates, Lakehurst,
Allentown, Pemberton, Farmingdale and Roosevelt.

This includes the following highways...
 New Jersey Turnpike between exits 8 and 9.
 Interstate 195 in New Jersey between mile markers 1 and 31.
 Interstate 295 in New Jersey between mile markers 62 and 69.
 Garden State Parkway between mile markers 118 and 122.

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.

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

Torrential rainfall is occurring with these storms, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3989 7479 4011 7468 4033 7475 4046 7425
      4045 7421 4022 7413 3986 7429
TIME...MOT...LOC 0248Z 264DEG 33KT 4028 7458 4012 7444 3991 7458 

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

Staarmann

703 
WWUS51 KPHI 180304
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
1104 PM EDT Sat Jul 17 2021

NJC005-021-023-025-029-180315-
/O.CON.KPHI.SV.W.0200.000000T0000Z-210718T0315Z/
Ocean NJ-Mercer NJ-Burlington NJ-Monmouth NJ-Middlesex NJ-
1104 PM EDT Sat Jul 17 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1115 PM EDT
FOR NORTHWESTERN OCEAN...NORTHEASTERN MERCER...EAST CENTRAL
BURLINGTON...CENTRAL MONMOUTH AND SOUTHERN MIDDLESEX COUNTIES...

At 1104 PM EDT, severe thunderstorms were located along a line
extending from Jamesburg to near Jacksons Mills to near Cedar Glen
Lakes, moving east at 35 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...
Toms River, Lakewood, Old Bridge, Jackson, Howell, East Brunswick,
Marlboro, Manalapan, Holmdel, Matawan, Jamesburg, Hightstown,
Cranbury, Presidential Lakes Estates, Lakehurst, Farmingdale,
Roosevelt, Brownville, East Freehold and Six Flags Theme Park.

This includes the following highways...
 New Jersey Turnpike between exits 8A and 9.
 Interstate 195 in New Jersey between mile markers 13 and 31.
 Garden State Parkway between mile markers 118 and 122.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Torrential rainfall is occurring with these storms, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3988 7465 4014 7447 4036 7464 4046 7425
      4045 7421 4022 7413 3986 7429
TIME...MOT...LOC 0304Z 265DEG 32KT 4037 7444 4013 7428 3992 7442 

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

Staarmann

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 17, 8:00 PM EDT	Severe Thunderstorm Warning	PHI	Burlington, Camden, Mercer, Monmouth	45 min
Jul 17, 8:09 PM EDT	Flash Flood Warning	PHI	Mercer, Somerset	4 hr
Jul 17, 8:35 PM EDT	Severe Thunderstorm Warning	PHI	Atlantic, Burlington, Camden, Gloucester	40 min
Jul 17, 8:36 PM EDT	Severe Thunderstorm Warning	PHI	Burlington, Mercer, Middlesex, Monmouth, Ocean, Somerset	54 min
Jul 17, 8:46 PM EDT	Special Marine Warning	PHI		59 min
Jul 17, 8:53 PM EDT	Areal Flood Advisory	PHI	Mercer, Middlesex, Monmouth	3 hr
Jul 17, 9:25 PM EDT	Areal Flood Advisory	PHI	Burlington, Camden, Gloucester, Salem	2 hr
Jul 17, 9:27 PM EDT	Severe Thunderstorm Warning	PHI	Gloucester, Salem	48 min
Jul 17, 9:30 PM EDT	Severe Thunderstorm Warning	PHI	Cape May	29 min
Jul 17, 9:36 PM EDT	Flash Flood Warning	PHI	Camden, Gloucester, Salem	2 hr
Jul 17, 9:44 PM EDT	Special Marine Warning	PHI		61 min
Jul 17, 9:48 PM EDT	Severe Thunderstorm Warning	PHI	Burlington, Camden, Gloucester, Mercer, Salem	42 min
Jul 17, 10:22 PM EDT	Tornado Warning	PHI	Burlington, Monmouth, Ocean	23 min
Jul 17, 10:27 PM EDT	Special Weather Statement	PHI	Burlington, Camden	33 min
Jul 17, 10:38 PM EDT	Tornado Warning	PHI	Burlington, Monmouth, Ocean	16 min
Jul 17, 10:43 PM EDT	Flash Flood Warning	PHI	Burlington, Mercer, Middlesex, Monmouth, Ocean	79 min
Jul 17, 10:47 PM EDT	Special Marine Warning	PHI		118 min
Jul 17, 10:51 PM EDT	Special Marine Warning	PHI		114 min
Jul 17, 11:07 PM EDT	Special Weather Statement	PHI	Middlesex	38 min
Jul 17, 11:08 PM EDT	Areal Flood Warning	PHI	Hunterdon	12 hr
Jul 17, 11:11 PM EDT	Special Weather Statement	PHI	Monmouth, Ocean	34 min
Jul 17, 11:20 PM EDT	Special Marine Warning	PHI		115 min
Jul 17, 11:26 PM EDT	Areal Flood Warning	PHI	Somerset	10 hr
Jul 18, 2:41 AM EDT	Areal Flood Warning	PHI	Mercer	4 hr
Jul 18, 3:48 AM EDT	River Flood Warning	PHI	Mercer	3 hr
Jul 18, 9:08 AM EDT	Areal Flood Warning	PHI	Somerset	2 hr
Jul 18, 11:03 AM EDT	River Flood Warning	PHI	Middlesex, Somerset	88 min
Jul 17, 8:44 PM EDT	Areal Flood Advisory	PHI	Chester, Montgomery	82 min
Jul 17, 8:57 PM EDT	Severe Thunderstorm Warning	PHI	Chester	48 min
Jul 17, 9:15 PM EDT	Areal Flood Advisory	PHI	Delaware, Montgomery, Philadelphia	2 hr

Nearby

Severe Thunderstorm Warnings in New Jersey, 2021 Severe Thunderstorm Warnings in Pennsylvania, 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.