Alert archive / New Jersey / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 304, NWS Philadelphia/Mount Holly

September 13, 20214 counties in New Jersey

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Sep 13, 2021, 9:53 PM EDT for 4 counties in New Jersey. It was in force for 52 min. 13 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
Sep 13, 2021, 9:53 PM EDT (01:53 UTC)
Expired
Sep 13, 2021, 10:45 PM EDT
In force
52 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Hail
0.88 in
Wind
60.0 mph

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

The radar

The Philadelphia radar (KDIX), 55 km from the middle of the area, began a volume at 01:53 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

TimeReportWhereRemark
Sep 13, 9:53 PM EDTTSTM WND DMG1 S New Brunswick, NJJONES AVE BETWEEN SEAMAN ST AND HANDY ST CLOSED DUE TO A LARGE TREE DOWN BLOCKING THE ROADWAY. TIME ESTIMATED FROM RADAR.
Sep 13, 10:02 PM EDTTSTM WND DMG1 Se Milltown, NJSEVERAL LARGE TREE LIMBS SNAPPED ALONG A CONCENTRATED PATH ALONG RYDERS LANE IN EAST BRUNSWICK. TIME ESTIMATED FROM RADAR.
Sep 13, 10:02 PM EDTTSTM WND DMG2 E Jamesburg, NJNORTH STATE HOME ROAD CLOSED BETWEEN SPOTSWOOD ENGLISHTOWN ROAD AND SPOTSWOOD GRAVEL HILL ROAD DUE TO TREES AND WIRES IN THE ROADWAY.TIME ESTIMATED FROM RADAR.
Sep 13, 10:02 PM EDTTSTM WND DMGConcordia, NJUNION VALLEY HALF ACRE ROAD CLOSED BETWEEN UNION VALLEY ROAD AND CRANBURY HALF ACRE ROAD DUE TO TREES AND WIRES IN THE ROADWAY. TIME ESTIMATED FROM RADAR. CORRECTED TIME.
Sep 13, 10:10 PM EDTTSTM WND DMGUnion Beach, NJDOWNED POLE ON NJ36 NORTHBOUND AT STONE ROAD, ALL LANES CLOSED. TIME ESTIMATED FROM RADAR.
Sep 13, 10:10 PM EDTHAIL 0.51 S Jamesburg, NJMONROE TOWNSHIP.
Sep 13, 10:14 PM EDTTSTM WND DMG1 Ene Navesink, NJDOWNED TREE ON NJ36 SOUTHBOUND IN MIDDLETOWN TOWNSHIP. TIME ESTIMATED FROM RADAR.
Sep 13, 10:14 PM EDTHAIL 0.51 Ese Keansburg, NJREPORT FROM MPING OF HALF-INCH HAIL.
Sep 13, 10:15 PM EDTTSTM WND DMGAtlantic Highlands, NJTREE LIMBS DOWN ALONG NJ ROUTE 36.
Sep 13, 10:15 PM EDTTSTM WND GST 67Port Monmouth, NJ67 MPH WIND GUST AT PORT MONMOUTH CWOP SITE.
Sep 13, 10:19 PM EDTTSTM WND GST 61Keansburg, NJ61MPH GUST AT WXFLOW SITE IN KEANSBURG.
Sep 13, 10:22 PM EDTTSTM WND DMG1 Ssw Colts Neck, NJREPORT FROM MPING: 3-INCH TREE LIMBS BROKEN; POWER POLES BROKEN. TIME ESTIMATED FROM RADAR.
Sep 13, 10:24 PM EDTTSTM WND GST 61Sandy Hook, NJMEASURED AT SANDY HOOK SITE.

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.

IssuedProductOfficeLasted
Sep 13, 7:44 PM EDTSevere Thunderstorm WatchSPC4 hr

The nearest sounding before it

Brookhaven, NY (KOKX), launched 00:00Z, 1.9 hours before the alert went out and 122 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-pSkew-T log-p diagram, Brookhaven, NY at 00:00Z on 2021-09-14Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 90 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Brookhaven, NY at 00:00Z on 2021-09-14The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 82 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
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
90 J/kg
Mixed-layer CIN
-236 J/kg
Mixed-layer LCL
1411 m above ground
0-6 km bulk shear
56 kt
0-1 km storm-relative helicity
82 m²/s²
0-3 km storm-relative helicity
139 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

477 
WUUS51 KPHI 140153
SVRPHI
NJC021-023-025-035-140245-
/O.NEW.KPHI.SV.W.0304.210914T0153Z-210914T0245Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
953 PM EDT Mon Sep 13 2021

The National Weather Service in Mount Holly NJ has issued a

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

* Until 1045 PM EDT.

* At 952 PM EDT, severe thunderstorms were located along a line
  extending from Carteret to Hopewell, moving east at 60 mph.

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

  SOURCE...Radar indicated.

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

* Locations impacted include...
  New Brunswick, Long Branch, Asbury Park, Sandy Hook, Somerset,
  Middletown, Old Bridge, East Brunswick, South Brunswick,
  Sayreville, North Brunswick, Marlboro, Manalapan, Tinton Falls,
  Holmdel, Princeton, Red Bank, Keansburg, Matawan and Jamesburg.

This includes the following highways...
 New Jersey Turnpike between exits 9 and 10.
 Garden State Parkway between mile markers 100 and 126.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

In addition to 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.

&&

LAT...LON 4017 7397 4034 7488 4049 7458 4050 7426
      4049 7428 4046 7426 4044 7420 4046 7418
      4045 7413 4041 7400 4041 7399 4048 7402
      4048 7401 4043 7397
TIME...MOT...LOC 0152Z 286DEG 50KT 4058 7423 4037 7476 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.88 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Gorse
3 follow-up statements
793 
WWUS51 KPHI 140206
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
1006 PM EDT Mon Sep 13 2021

NJC035-140216-
/O.CAN.KPHI.SV.W.0304.000000T0000Z-210914T0245Z/
Somerset NJ-
1006 PM EDT Mon Sep 13 2021

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

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

LAT...LON 4017 7397 4030 7467 4044 7454 4049 7447
      4050 7428 4046 7426 4044 7420 4046 7418
      4045 7413 4041 7403 4041 7398 4047 7401
      4048 7401 4043 7397
TIME...MOT...LOC 0206Z 286DEG 50KT 4054 7404 4033 7457 

$$

NJC021-023-025-140245-
/O.CON.KPHI.SV.W.0304.000000T0000Z-210914T0245Z/
Mercer NJ-Monmouth NJ-Middlesex NJ-
1006 PM EDT Mon Sep 13 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1045 PM EDT
FOR EAST CENTRAL MERCER...NORTHEASTERN MONMOUTH AND MIDDLESEX
COUNTIES...

At 1006 PM EDT, severe thunderstorms were located along a line
extending from near Oakwood to Princeton Meadows, moving east at 60
mph.

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

SOURCE...Radar indicated.

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

Locations impacted include...
New Brunswick, Long Branch, Asbury Park, Sandy Hook, Somerset,
Middletown, Old Bridge, East Brunswick, South Brunswick, Sayreville,
North Brunswick, Marlboro, Manalapan, Tinton Falls, Holmdel, Red
Bank, Keansburg, Matawan, Jamesburg and Hightstown.

This includes the following highways...
 New Jersey Turnpike between exits 9 and 10.
 Garden State Parkway between mile markers 100 and 126.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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.

&&

LAT...LON 4017 7397 4030 7467 4044 7454 4049 7447
      4050 7428 4046 7426 4044 7420 4046 7418
      4045 7413 4041 7403 4041 7398 4047 7401
      4048 7401 4043 7397
TIME...MOT...LOC 0206Z 286DEG 50KT 4054 7404 4033 7457 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.88 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Gorse
137 
WWUS51 KPHI 140224
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
1024 PM EDT Mon Sep 13 2021

NJC021-023-140234-
/O.CAN.KPHI.SV.W.0304.000000T0000Z-210914T0245Z/
Mercer NJ-Middlesex NJ-
1024 PM EDT Mon Sep 13 2021

...THE SEVERE THUNDERSTORM WARNING FOR EAST CENTRAL MERCER AND
MIDDLESEX COUNTIES IS CANCELLED...

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

LAT...LON 4017 7397 4024 7434 4045 7413 4041 7403
      4041 7398 4046 7401 4047 7400 4043 7397
TIME...MOT...LOC 0224Z 289DEG 48KT 4044 7389 4026 7413 4023 7428 

$$

NJC025-140245-
/O.CON.KPHI.SV.W.0304.000000T0000Z-210914T0245Z/
Monmouth NJ-
1024 PM EDT Mon Sep 13 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1045 PM EDT
FOR NORTHEASTERN MONMOUTH COUNTY...

At 1024 PM EDT, severe thunderstorms were located along a line
extending from near Sandy Hook to Tinton Falls to West Freehold,
moving east at 55 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...
Long Branch, Asbury Park, Sandy Hook, Middletown, Marlboro, Tinton
Falls, Holmdel, Red Bank, Keansburg, Highlands, East Freehold, West
Freehold, Elberon, Navesink, Collingwood Park, Lincroft, Eatontown,
Freehold, West Long Branch and Rumson.

This includes Garden State Parkway between mile markers 100 and 116.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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.

&&

LAT...LON 4017 7397 4024 7434 4045 7413 4041 7403
      4041 7398 4046 7401 4047 7400 4043 7397
TIME...MOT...LOC 0224Z 289DEG 48KT 4044 7389 4026 7413 4023 7428 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Gorse
617 
WWUS51 KPHI 140237
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
1037 PM EDT Mon Sep 13 2021

NJC025-140246-
/O.EXP.KPHI.SV.W.0304.000000T0000Z-210914T0245Z/
Monmouth NJ-
1037 PM EDT Mon Sep 13 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN MONMOUTH COUNTY
WILL EXPIRE AT 1045 PM EDT...
    
The storms which prompted the warning continue to move out of the 
area. Therefore, the warning will be allowed to expire.

LAT...LON 4017 7397 4024 7434 4045 7413 4041 7403
      4041 7398 4046 7401 4047 7400 4043 7397
TIME...MOT...LOC 0236Z 286DEG 50KT 4040 7372 4022 7396 4019 7411 

$$

Gorse

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 13, 8:41 PM EDTSevere Thunderstorm WarningPHIHunterdon, Warren49 min
Sep 13, 9:03 PM EDTAreal Flood AdvisoryPHIHunterdon, Morris, Somerset, Sussex, Warren109 min
Sep 13, 9:03 PM EDTSevere Thunderstorm WarningPHIHunterdon, Morris, Somerset, Warren57 min
Sep 13, 9:12 PM EDTFlash Flood WarningPHIHunterdon, Morris, Warren114 min
Sep 13, 9:21 PM EDTSevere Thunderstorm WarningPHIHunterdon, Somerset, Warren38 min
Sep 13, 9:34 PM EDTSevere Thunderstorm WarningPHIMiddlesex, Morris, Somerset38 min
Sep 13, 10:03 PM EDTSpecial Marine WarningPHI57 min

Nearby

Severe Thunderstorm Warnings in New Jersey, 2021Every 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.