Alert archive / New Jersey / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 191, NWS Philadelphia/Mount Holly

July 31, 20207 counties in New Jersey

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 31, 2020, 12:33 AM EDT for 7 counties in New Jersey. It was in force for 42 min. 11 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 31, 2020, 12:33 AM EDT (04:33 UTC)
Expired: Jul 31, 2020, 1:15 AM EDT
In force: 42 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

Counties Hunterdon County, NJ, Mercer County, NJ, Middlesex County, NJ, Monmouth County, NJ, Morris County, NJ, Ocean County, NJ, Somerset County, NJ

The radar

The Philadelphia radar (KDIX), 63 km from the middle of the area, began a volume at 04:36 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 31, 12:43 AM EDT	TSTM WND DMG	2 Ssw North Brunswick, NJ	SEVERAL REPORTS OF WIRES DOWN NEAR ADAMS LANE IN NORTH BRUNSWICK. TIME ESTIMATED FROM RADAR.
Jul 31, 12:43 AM EDT	TSTM WND DMG	2 Ssw North Brunswick, NJ	CORRECTS PREVIOUS TSTM WND DMG REPORT FROM 2 SSW NORTH BRUNSWICK. SEVERAL REPORTS OF WIRES DOWN NEAR ADAMS LANE IN NORTH BRUNSWICK. TIME ESTIMATED FROM RADAR.
Jul 31, 12:48 AM EDT	TSTM WND DMG	New Brunswick, NJ	CORRECTS PREVIOUS REPORT FROM NEW BRUNSWICK. SEVERAL REPORTS OF TREE LIMBS AND WIRES DOWN IN THE NEW BRUNSWICK AREA. TIME ESTIMATED FROM RADAR.
Jul 31, 12:50 AM EDT	TSTM WND DMG	2 Ese Metuchen, NJ	UPDATES PREVIOUS TSTM WND DMG REPORT FROM 2 ESE METUCHEN. SEVERAL DOWNED TREES AND WIRES NEAR HOOVER AVENUE IN METUCHEN. TIME ESTIMATED FROM RADAR.
Jul 31, 12:50 AM EDT	TSTM WND DMG	2 Ese Metuchen, NJ	DOWNED POWER LINES NEAR HOOVER AVENUE IN METUCHEN. TIME ESTIMATED FROM RADAR.
Jul 31, 12:50 AM EDT	TSTM WND DMG	Somerville, NJ	DOWNED TREES AND POWER OUTAGES REPORTED IN SOMERVILLE. TIME ESTIMATED FROM RADAR.
Jul 31, 12:51 AM EDT	TSTM WND DMG	2 Sse Manville, NJ	SEVERAL REPORTS OF POWER LINES DOWN NEAR MANVILLE. TIME ESTIMATED FROM RADAR.
Jul 31, 12:57 AM EDT	TSTM WND DMG	1 Ssw Matawan, NJ	DOWNED TREES AND WIRES NEAR TINA PLACE IN MATAWAN. TIME ESTIMATED FROM RADAR.
Jul 31, 1:00 AM EDT	TSTM WND DMG	1 Se Keyport, NJ	TREE DOWN ON WIRES ON ATLANTIC ST. TIME ESTIMATED FROM RADAR.
Jul 31, 1:22 AM EDT	TSTM WND DMG	1 Se Iselin, NJ	DOWNED WIRES ON WOODBRIDGE CENTER DRIVE. TIME ESTIMATED FROM RADAR.
Jul 31, 1:23 AM EDT	TSTM WND DMG	Woodbridge, NJ	SEVERAL REPORTS OF DOWNED POWER LINES BETWEEN FORDS AND COLONIA. TIME ESTIMATED FROM RADAR.

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, 4.6 hours before the alert went out and 123 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: 2515 J/kg
Mixed-layer CIN: -27 J/kg
Mixed-layer LCL: 895 m above ground
0-6 km bulk shear: 34 kt
0-1 km storm-relative helicity: 79 m²/s²
0-3 km storm-relative helicity: 102 m²/s²
Significant tornado parameter: 0.8
Supercell composite: 4.9

Open this sounding in Storm Lab

The text

As transmitted.

121 
WUUS51 KPHI 310433
SVRPHI
NJC019-021-023-025-027-029-035-310515-
/O.NEW.KPHI.SV.W.0191.200731T0433Z-200731T0515Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
1233 AM EDT Fri Jul 31 2020

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  North central Ocean County in southern New Jersey...
  Southeastern Morris County in northern New Jersey...
  East central Hunterdon County in northwestern New Jersey...
  Northeastern Mercer County in central New Jersey...
  Somerset County in northern New Jersey...
  Monmouth County in central New Jersey...
  Middlesex County in northern New Jersey...

* Until 115 AM EDT.

* At 1232 AM EDT, severe thunderstorms were located along a line
  extending from White House Station to near Vista Center, moving
  east at 45 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

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

* Locations impacted include...
  New Brunswick, Perth Amboy, Long Branch, Somerville, Sandy Hook,
  Somerset, Edison, Middletown, Old Bridge, Howell, East Brunswick,
  Bridgewater, South Brunswick, Sayreville, North Brunswick,
  Marlboro, Manalapan, Carteret, Tinton Falls and Holmdel.

This includes the following highways...
 New Jersey Turnpike between exits 8A and 13.
 Interstate 78 in New Jersey between mile markers 26 and 42.
 Interstate 195 in New Jersey between mile markers 13 and 28.
 Interstate 287 in New Jersey between mile markers 0 and 29.
 Garden State Parkway between mile markers 102 and 134.

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 4028 7397 4008 7440 4058 7495 4079 7437
      4074 7437 4067 7446 4065 7441 4060 7446
      4060 7421 4056 7421 4055 7425 4050 7428
      4044 7420 4046 7417 4041 7399 4048 7402
      4047 7400 4043 7397
TIME...MOT...LOC 0432Z 250DEG 40KT 4060 7477 4017 7436 

HAIL...<.75IN
WIND...60MPH
 
$$

JEO

2 follow-up statements

301 
WWUS51 KPHI 310453
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
1253 AM EDT Fri Jul 31 2020

NJC021-029-310503-
/O.CAN.KPHI.SV.W.0191.000000T0000Z-200731T0515Z/
Ocean NJ-Mercer NJ-
1253 AM EDT Fri Jul 31 2020

...THE SEVERE THUNDERSTORM WARNING FOR NORTH CENTRAL OCEAN AND
NORTHEASTERN MERCER COUNTIES IS CANCELLED...

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

LAT...LON 4033 7405 4019 7435 4059 7484 4079 7437
      4074 7437 4067 7446 4065 7441 4060 7446
      4060 7421 4056 7421 4050 7428 4046 7426
      4044 7408 4041 7403 4043 7400 4044 7400
      4048 7401 4042 7398 4043 7398 4042 7397
TIME...MOT...LOC 0453Z 250DEG 40KT 4067 7452 4024 7411 

$$

NJC019-023-025-027-035-310515-
/O.CON.KPHI.SV.W.0191.000000T0000Z-200731T0515Z/
Morris NJ-Hunterdon NJ-Somerset NJ-Monmouth NJ-Middlesex NJ-
1253 AM EDT Fri Jul 31 2020

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

At 1253 AM EDT, severe thunderstorms were located along a line
extending from Millington to Collingwood Park, moving east at 45 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
New Brunswick, Perth Amboy, Somerville, Sandy Hook, Somerset, Edison,
Middletown, Old Bridge, East Brunswick, Bridgewater, South Brunswick,
Sayreville, North Brunswick, Marlboro, Manalapan, Carteret, Tinton
Falls, Holmdel, Madison and Middlesex.

This includes the following highways...
 New Jersey Turnpike between exits 9 and 13.
 Interstate 78 in New Jersey between mile markers 28 and 42.
 Interstate 287 in New Jersey between mile markers 0 and 28.
 Garden State Parkway between mile markers 109 and 134.

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.

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

&&

LAT...LON 4033 7405 4019 7435 4059 7484 4079 7437
      4074 7437 4067 7446 4065 7441 4060 7446
      4060 7421 4056 7421 4050 7428 4046 7426
      4044 7408 4041 7403 4043 7400 4044 7400
      4048 7401 4042 7398 4043 7398 4042 7397
TIME...MOT...LOC 0453Z 250DEG 40KT 4067 7452 4024 7411 

TORNADO...POSSIBLE
HAIL...<.75IN
WIND...60MPH
 
$$

JEO

234 
WWUS51 KPHI 310513
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
113 AM EDT Fri Jul 31 2020

NJC019-023-025-027-035-310522-
/O.EXP.KPHI.SV.W.0191.000000T0000Z-200731T0515Z/
Morris NJ-Hunterdon NJ-Somerset NJ-Monmouth NJ-Middlesex NJ-
113 AM EDT Fri Jul 31 2020

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN MORRIS...EAST
CENTRAL HUNTERDON...SOMERSET...CENTRAL MONMOUTH AND MIDDLESEX
COUNTIES WILL EXPIRE AT 115 AM EDT...
    
The storms which prompted the warning have moved out of the area.
Therefore, the warning will be allowed to expire.

A new Severe Thunderstorm Warning still remains in effect for
portions of Morris, Somerset, Monmouth, and Middlesex Counties until 
145 AM.

LAT...LON 4033 7405 4019 7435 4059 7484 4079 7437
      4074 7437 4067 7446 4065 7441 4060 7446
      4060 7421 4056 7421 4050 7428 4046 7426
      4044 7408 4041 7403 4043 7400 4044 7400
      4048 7401 4042 7398 4043 7398 4042 7397
TIME...MOT...LOC 0512Z 250DEG 40KT 4067 7452 4024 7411 

$$

JEO

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 30, 10:15 PM EDT	Special Marine Warning	PHI		60 min
Jul 30, 10:36 PM EDT	Special Weather Statement	PHI	Atlantic, Camden, Cumberland, Gloucester, Salem	39 min
Jul 30, 11:06 PM EDT	Severe Thunderstorm Warning	PHI	Atlantic, Burlington, Camden, Cumberland, Gloucester, Salem	39 min
Jul 30, 11:35 PM EDT	Severe Thunderstorm Warning	PHI	Atlantic, Burlington, Camden, Mercer, Monmouth, Ocean	40 min
Jul 30, 11:40 PM EDT	Special Weather Statement	PHI	Hunterdon	50 min
Jul 30, 11:51 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Mercer, Somerset, Warren	54 min
Jul 31, 12:10 AM EDT	Severe Thunderstorm Warning	PHI	Burlington, Mercer, Middlesex, Monmouth, Ocean, Somerset	50 min
Jul 31, 12:21 AM EDT	Areal Flood Advisory	PHI	Hunterdon, Mercer	4 hr
Jul 31, 12:54 AM EDT	Areal Flood Advisory	PHI	Hunterdon, Mercer, Middlesex, Monmouth, Somerset	4 hr
Jul 31, 1:10 AM EDT	Severe Thunderstorm Warning	PHI	Middlesex, Monmouth, Morris, Somerset	35 min
Jul 31, 1:29 AM EDT	Flash Flood Warning	PHI	Middlesex, Somerset	4 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.