Alert archive / New Jersey / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 136, NWS Philadelphia/Mount Holly

July 6, 20215 counties in New Jersey; Bucks County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 6, 2021, 8:50 PM EDT for 5 counties in New Jersey; Bucks County, Pennsylvania. It was in force for 40 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 6, 2021, 8:50 PM EDT (00:50 UTC)
Expired: Jul 6, 2021, 9:30 PM EDT
In force: 40 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Hunterdon County, NJ, Mercer County, NJ, Middlesex County, NJ, Monmouth County, NJ, Somerset County, NJ, Bucks County, PA

The radar

The Philadelphia radar (KDIX), 53 km from the middle of the area, began a volume at 00:52 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 6, 9:24 PM EDT	TSTM WND DMG	Hopewell, NJ	NUMEROUS TREES SNAPPED AND UPROOTED IN HOPEWELL TWP. TIME ESTIMATED FROM RADAR.
Jul 6, 9:31 PM EDT	HAIL 1	3 Nw Pennington, NJ	MPING REPORT.
Jul 6, 9:40 PM EDT	HAIL 0.5	Washington Crossing, PA	REPORT FROM MPING: HALF-INCH (0.50 IN.).

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 6, 1:32 PM EDT	Severe Thunderstorm Watch	SPC	8 hr

The nearest sounding before it

Brookhaven, NY (KOKX), launched 00:00Z, 0.8 hours before the alert went out and 173 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: 1647 J/kg
Mixed-layer CIN: -86 J/kg
Mixed-layer LCL: 876 m above ground
0-6 km bulk shear: 25 kt
0-1 km storm-relative helicity: 85 m²/s²
0-3 km storm-relative helicity: 93 m²/s²
Significant tornado parameter: 0.3
Supercell composite: 3.3

Open this sounding in Storm Lab

The text

As transmitted.

182 
WUUS51 KPHI 070050
SVRPHI
NJC019-021-023-025-035-PAC017-070130-
/O.NEW.KPHI.SV.W.0136.210707T0050Z-210707T0130Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
850 PM EDT Tue Jul 6 2021

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Southeastern Hunterdon County in northwestern New Jersey...
  Mercer County in central New Jersey...
  Southwestern Somerset County in northern New Jersey...
  Southwestern Monmouth County in central New Jersey...
  Southwestern Middlesex County in northern New Jersey...
  East central Bucks County in southeastern Pennsylvania...

* Until 930 PM EDT.

* At 850 PM EDT, a severe thunderstorm was located over New Hope, or
  12 miles northwest of Trenton, 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...
  Trenton, East Brunswick, South Brunswick, North Brunswick, Ewing,
  Princeton, Jamesburg, Hightstown, Cranbury, Pennington, New Hope,
  Yardley, Hopewell, Allentown, Roosevelt, Rocky Hill, Stockton,
  Skillman, White Horse and Sergeantsville.

This includes the following highways...
 New Jersey Turnpike between exits 8 and 9.
 Interstate 195 in New Jersey between mile markers 2 and 14.
 Interstate 295 in New Jersey between mile markers 61 and 76.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Prepare immediately for large hail and damaging winds. People outside
should move immediately to shelter inside a strong building. Stay
away from windows.

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

&&

LAT...LON 4029 7505 4046 7500 4045 7436 4012 7448
TIME...MOT...LOC 0050Z 281DEG 29KT 4036 7493 

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

Staarmann

1 follow-up statement

483 
WWUS51 KPHI 070108
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
908 PM EDT Tue Jul 6 2021

NJC019-021-023-025-035-PAC017-070130-
/O.CON.KPHI.SV.W.0136.000000T0000Z-210707T0130Z/
Hunterdon NJ-Mercer NJ-Somerset NJ-Monmouth NJ-Middlesex NJ-Bucks PA-
908 PM EDT Tue Jul 6 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 930 PM EDT
FOR SOUTHEASTERN HUNTERDON...MERCER...SOUTHWESTERN SOMERSET...
SOUTHWESTERN MONMOUTH...SOUTHWESTERN MIDDLESEX AND EAST CENTRAL BUCKS
COUNTIES...

At 908 PM EDT, a severe thunderstorm was located over Pennington, or
9 miles north of Trenton, moving east at 30 mph.

HAZARD...60 mph wind gusts and half dollar 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...
Trenton, East Brunswick, South Brunswick, Ewing, Princeton,
Jamesburg, Hightstown, Cranbury, Pennington, New Hope, Hopewell,
Roosevelt, Rocky Hill, Washington Crossing, Skillman, Princeton
Meadows, Windsor, Kingston, Dayton and Plainsboro Center.

This includes the following highways...
 New Jersey Turnpike between exits 8A and 9.
 Interstate 195 in New Jersey between mile markers 12 and 14.
 Interstate 295 in New Jersey between mile markers 64 and 75.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Prepare immediately for large hail and damaging winds. People outside
should seek shelter inside a well-built structure and away from
windows.

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.

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

&&

LAT...LON 4030 7496 4043 7496 4045 7436 4016 7446
TIME...MOT...LOC 0108Z 277DEG 24KT 4036 7480 

HAIL...1.25IN
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 6, 8:03 PM EDT	Special Weather Statement	PHI	Burlington, Ocean	42 min
Jul 6, 8:11 PM EDT	Special Marine Warning	PHI		82 min
Jul 6, 8:24 PM EDT	Special Marine Warning	PHI		2 hr
Jul 6, 8:29 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Warren	46 min
Jul 6, 8:37 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Middlesex, Monmouth, Morris, Somerset	53 min
Jul 6, 9:04 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Mercer, Middlesex, Somerset	41 min
Jul 6, 9:10 PM EDT	Areal Flood Advisory	PHI	Hunterdon, Mercer, Middlesex, Monmouth, Morris, Somerset and 1 more	2 hr
Jul 6, 9:29 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Mercer, Middlesex, Monmouth, Morris, Somerset	61 min
Jul 6, 9:37 PM EDT	Special Marine Warning	PHI		113 min
Jul 6, 9:48 PM EDT	Severe Thunderstorm Warning	PHI	Burlington, Mercer, Middlesex, Monmouth, Ocean	57 min
Jul 6, 10:21 PM EDT	Severe Thunderstorm Warning	PHI	Burlington, Camden	39 min
Jul 6, 10:50 PM EDT	Areal Flood Advisory	PHI	Monmouth, Ocean	2 hr
Jul 6, 10:54 PM EDT	Special Weather Statement	PHI	Burlington	51 min
Jul 6, 11:11 PM EDT	Special Weather Statement	PHI	Burlington	19 min
Jul 6, 11:30 PM EDT	Severe Thunderstorm Warning	PHI	Atlantic, Burlington, Camden, Ocean	45 min
Jul 6, 11:39 PM EDT	Special Marine Warning	PHI		66 min
Jul 6, 11:55 PM EDT	Special Weather Statement	PHI	Monmouth	50 min
Jul 7, 12:01 AM EDT	Areal Flood Advisory	PHI	Middlesex, Monmouth	71 min
Jul 7, 12:10 AM EDT	Special Marine Warning	PHI		95 min
Jul 7, 11:19 AM EDT	Tropical Storm Watch	PHI	Atlantic, Burlington, Cape May, Monmouth, Ocean	18 hr
Jul 7, 3:32 PM EDT	Flash Flood Watch	PHI	Atlantic, Burlington, Camden, Cape May, Cumberland, Gloucester and 10 more	42 hr
Jul 6, 8:16 PM EDT	Special Weather Statement	PHI	Lehigh	29 min
Jul 6, 10:08 PM EDT	Special Weather Statement	PHI	Philadelphia	37 min

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.