Alert archive / New Jersey / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 181, NWS Philadelphia/Mount Holly

July 24, 20204 counties in New Jersey

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 24, 2020, 12:23 AM EDT for 4 counties in New Jersey. It was in force for 52 min. 10 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 24, 2020, 12:23 AM EDT (04:23 UTC)
Expired: Jul 24, 2020, 1:15 AM EDT
In force: 52 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

Counties Mercer County, NJ, Middlesex County, NJ, Monmouth County, NJ, Somerset County, NJ

The radar

The Philadelphia radar (KDIX), 58 km from the middle of the area, began a volume at 04:26 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 24, 12:26 AM EDT	HAIL 0.25	1 Nw North Princeton, NJ	TIME ESTIMATED FROM RADAR.
Jul 24, 12:26 AM EDT	HAIL 0.25	2 Wnw North Princeton, NJ	TIME ESTIMATED FROM RADAR.
Jul 24, 12:35 AM EDT	TSTM WND DMG	2 Ne Spotswood, NJ	WIRES DOWN IN THE OLD BRIDGE AREA. TIME ESTIMATED FROM RADAR.
Jul 24, 12:40 AM EDT	TSTM WND DMG	2 Ene Old Bridge, NJ	WIRES DOWN NEAR TEXAS ROAD IN SPRING VALLEY. TIME ESTIMATED FROM RADAR.
Jul 24, 12:40 AM EDT	TSTM WND DMG	Middletown, NJ	SEVERAL REPORTS OF WIRES DOWN IN MIDDLETOWN. TIME ESTIMATED FROM RADAR.
Jul 24, 12:44 AM EDT	TSTM WND DMG	1 Sse Parlin, NJ	SEVERAL REPORTS OF WIRES DOWN IN MADISON PARK. TIME ESTIMATED FROM RADAR.
Jul 24, 12:49 AM EDT	TSTM WND DMG	1 Nw Hazlet, NJ	DOWNED UTILITY NEAR JACKSON STREET IN KEYPORT. TIME ESTIMATED FROM RADAR.
Jul 24, 12:49 AM EDT	TSTM WND DMG	1 Sw South Amboy, NJ	DOWNED POWER POLE AND WIRES ON U.S. HIGHWAY 9 NEAR THE STATE HIGHWAY 35 INTERCHANGE. TIME ESTIMATED FROM RADAR.
Jul 24, 1:24 AM EDT	MARINE TSTM WIND 49	8 S Seagate, NY	SANDY HOOK STATION MEASURED WIND GUST OF 42.9 KTS
Jul 24, 1:24 AM EDT	MARINE TSTM WIND 49	Sandy Hook, NJ

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Brookhaven, NY (KOKX), launched 00:00Z, 4.4 hours before the alert went out and 120 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: 1702 J/kg
Mixed-layer CIN: -49 J/kg
Mixed-layer LCL: 797 m above ground
0-6 km bulk shear: 20 kt
0-1 km storm-relative helicity: 111 m²/s²
0-3 km storm-relative helicity: 116 m²/s²
Significant tornado parameter: 0.6
Supercell composite: 4.0

Open this sounding in Storm Lab

The text

As transmitted.

020 
WUUS51 KPHI 240423
SVRPHI
NJC021-023-025-035-240515-
/O.NEW.KPHI.SV.W.0181.200724T0423Z-200724T0515Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
1223 AM EDT Fri Jul 24 2020

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  North central Mercer County in central New Jersey...
  Southeastern Somerset County in northern New Jersey...
  Northeastern Monmouth County in central New Jersey...
  Central Middlesex County in northern New Jersey...

* Until 115 AM EDT.

* At 1223 AM EDT, severe thunderstorms were located along a line
  extending from Skillman to near Holmdel, moving east at 10 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...
  New Brunswick, Sandy Hook, Somerset, Middletown, Old Bridge, East
  Brunswick, South Brunswick, Sayreville, North Brunswick, Holmdel,
  Princeton, Red Bank, Keansburg, Matawan, Jamesburg, Highlands,
  Hopewell, Rocky Hill, Millstone and Skillman.

This includes the following highways...
 New Jersey Turnpike near exit 10.
 Garden State Parkway between mile markers 111 and 126.

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.

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

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

&&

LAT...LON 4038 7396 4033 7413 4037 7483 4053 7455
      4050 7426 4049 7428 4046 7426 4044 7420
      4046 7418 4045 7413 4042 7405 4041 7398
      4048 7402 4048 7401 4043 7397
TIME...MOT...LOC 0423Z 258DEG 10KT 4041 7471 4038 7420 

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

Staarmann

2 follow-up statements

855 
WWUS51 KPHI 240449
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
1249 AM EDT Fri Jul 24 2020

NJC021-240459-
/O.CAN.KPHI.SV.W.0181.000000T0000Z-200724T0515Z/
Mercer NJ-
1249 AM EDT Fri Jul 24 2020

...THE SEVERE THUNDERSTORM WARNING FOR NORTH CENTRAL MERCER COUNTY IS
CANCELLED...

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

LAT...LON 4038 7396 4034 7410 4042 7474 4053 7455
      4050 7427 4049 7428 4046 7426 4044 7420
      4046 7418 4041 7398 4048 7402 4048 7401
      4043 7397
TIME...MOT...LOC 0449Z 256DEG 12KT 4042 7459 4043 7431 4039 7408 

$$

NJC023-025-035-240515-
/O.CON.KPHI.SV.W.0181.000000T0000Z-200724T0515Z/
Somerset NJ-Monmouth NJ-Middlesex NJ-
1249 AM EDT Fri Jul 24 2020

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 115 AM EDT
FOR SOUTHEASTERN SOMERSET...NORTHEASTERN MONMOUTH AND CENTRAL
MIDDLESEX COUNTIES...

At 1249 AM EDT, severe thunderstorms were located along a line
extending from Kendall Park to near Brownville to near Middletown,
moving east at 15 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...
New Brunswick, Sandy Hook, Somerset, Middletown, Old Bridge, East
Brunswick, South Brunswick, Sayreville, North Brunswick, Red Bank,
Matawan, Highlands, Millstone, Skillman, Brownville, North Brunswick
Township, Navesink, Kendall Park, Belle Mead and Lincroft.

This includes the following highways...
 New Jersey Turnpike near exit 10.
 Garden State Parkway between mile markers 111 and 126.

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 these storms.
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.

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

&&

LAT...LON 4038 7396 4034 7410 4042 7474 4053 7455
      4050 7427 4049 7428 4046 7426 4044 7420
      4046 7418 4041 7398 4048 7402 4048 7401
      4043 7397
TIME...MOT...LOC 0449Z 256DEG 12KT 4042 7459 4043 7431 4039 7408 

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

Staarmann

311 
WWUS51 KPHI 240508
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
108 AM EDT Fri Jul 24 2020

NJC023-025-035-240517-
/O.EXP.KPHI.SV.W.0181.000000T0000Z-200724T0515Z/
Somerset NJ-Monmouth NJ-Middlesex NJ-
108 AM EDT Fri Jul 24 2020

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN SOMERSET...
NORTHEASTERN MONMOUTH AND CENTRAL MIDDLESEX COUNTIES WILL EXPIRE AT
115 AM EDT...
            
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 will be allowed to expire.  However gusty
winds and heavy rain are still possible with these thunderstorms.

LAT...LON 4038 7396 4034 7410 4042 7474 4053 7455
      4050 7427 4049 7428 4046 7426 4044 7420
      4046 7418 4041 7398 4048 7402 4048 7401
      4043 7397
TIME...MOT...LOC 0507Z 258DEG 10KT 4043 7453 4044 7425 4040 7402 

$$

Staarmann

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 23, 8:04 PM EDT	Severe Thunderstorm Warning	PHI	Middlesex, Monmouth	26 min
Jul 23, 11:16 PM EDT	Severe Thunderstorm Warning	PHI	Gloucester, Salem	44 min
Jul 23, 11:27 PM EDT	Special Marine Warning	PHI		63 min
Jul 24, 12:14 AM EDT	Special Weather Statement	PHI	Middlesex	31 min
Jul 24, 12:31 AM EDT	Areal Flood Advisory	PHI	Hunterdon, Mercer, Middlesex, Monmouth, Somerset	119 min
Jul 24, 12:51 AM EDT	Special Marine Warning	PHI		54 min
Jul 24, 1:13 AM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Mercer, Middlesex, Monmouth, Somerset	62 min
Jul 24, 1:28 AM EDT	Flash Flood Warning	PHI	Mercer, Middlesex, Monmouth, Somerset	4 hr
Jul 24, 1:36 AM EDT	Special Marine Warning	PHI		84 min
Jul 24, 2:18 AM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Middlesex, Morris, Somerset	42 min
Jul 24, 5:04 AM EDT	Special Marine Warning	PHI		56 min
Jul 24, 10:43 AM EDT	Flash Flood Warning	PHI	Camden	76 min
Jul 24, 11:42 AM EDT	Special Marine Warning	PHI		63 min
Jul 24, 12:43 PM EDT	Areal Flood Advisory	PHI	Ocean	3 hr
Jul 24, 1:09 PM EDT	Areal Flood Advisory	PHI	Monmouth, Ocean	110 min
Jul 24, 1:40 PM EDT	Special Weather Statement	PHI	Atlantic	35 min
Jul 24, 1:43 PM EDT	Areal Flood Advisory	PHI	Burlington, Mercer, Monmouth	3 hr
Jul 24, 2:02 PM EDT	Areal Flood Advisory	PHI	Atlantic, Burlington, Camden, Gloucester	3 hr
Jul 24, 2:19 PM EDT	Areal Flood Advisory	PHI	Burlington, Camden, Gloucester	2 hr
Jul 24, 2:26 PM EDT	Flash Flood Warning	PHI	Burlington	2 hr
Jul 24, 2:39 PM EDT	Areal Flood Advisory	PHI	Burlington, Ocean	3 hr
Jul 24, 2:42 PM EDT	Areal Flood Advisory	PHI	Burlington, Ocean	2 hr
Jul 24, 3:34 PM EDT	Flash Flood Warning	PHI	Atlantic, Burlington, Ocean	2 hr
Jul 24, 4:22 PM EDT	Areal Flood Advisory	PHI	Atlantic, Cape May	3 hr
Jul 24, 4:58 PM EDT	Areal Flood Advisory	PHI	Cape May	2 hr

Nearby

Severe Thunderstorm Warnings in New Jersey, 2020 Every severe thunderstorm warning in 2020

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.