Alert archive / New Jersey / Tornado Warnings in 2023

Tornado Warning 34, NWS Philadelphia/Mount Holly

August 13, 2023Morris County, Somerset County, New Jersey

NWS Philadelphia/Mount Holly issued this tornado warning at Aug 13, 2023, 1:49 AM EDT for Morris County, Somerset County, New Jersey. It was in force for 26 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
Aug 13, 2023, 1:49 AM EDT (05:49 UTC)
Expired
Aug 13, 2023, 2:15 AM EDT
In force
26 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Tornado
Radar indicated
Hail
0.75 in

Counties Morris County, NJ, Somerset County, NJ

The radar

The Philadelphia radar (KDIX), 86 km from the middle of the area, began a volume at 05:50 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
Aug 13, 1:53 AM EDTTSTM WND DMG1 Wsw Millington, NJTrees down on Keats Road. Time estimated from radar.
Aug 13, 1:58 AM EDTTSTM WND DMG1 Sw Millington, NJTwo trees on a house and also some snapped tree tops on Haas Road between Keats Road and Pond Hill Road.Time estimated from radar.
Aug 13, 1:58 AM EDTTSTM WND DMGBasking Ridge, NJSeveral large tree limbs down. Photos received via social media. 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, 5.8 hours before the alert went out and 133 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 2023-08-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 358 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 2023-08-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 102 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
358 J/kg
Mixed-layer CIN
-89 J/kg
Mixed-layer LCL
1179 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
102 m²/s²
0-3 km storm-relative helicity
113 m²/s²
Significant tornado parameter
0.1
Supercell composite
2.5

Open this sounding in Storm Lab

The text

As transmitted.

667 
WFUS51 KPHI 130549
TORPHI
NJC027-035-130615-
/O.NEW.KPHI.TO.W.0034.230813T0549Z-230813T0615Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Mount Holly NJ
149 AM EDT Sun Aug 13 2023

The National Weather Service in Mount Holly NJ has issued a

* Tornado Warning for...
  Southeastern Morris County in northern New Jersey...
  Northeastern Somerset County in northern New Jersey...

* Until 215 AM EDT.
    
* At 149 AM EDT, a severe thunderstorm capable of producing a tornado
  was located over Bridgewater, or near Somerville, moving northeast
  at 40 mph.

  HAZARD...Tornado.

  SOURCE...Radar indicated rotation.

  IMPACT...Flying debris will be dangerous to those caught without 
           shelter. Mobile homes will be damaged or destroyed. 
           Damage to roofs, windows, and vehicles will occur.  Tree 
           damage is likely.

* Locations impacted include...
  Morristown, Madison, Florham Park, East Hanover, Chatham, Far
  Hills, Millington, Basking Ridge, Watchung and Hanover Township.

This includes the following highways...
 Interstate 78 in New Jersey between mile markers 31 and 43.
 Interstate 80 in New Jersey near mile marker 46.
 Interstate 287 in New Jersey between mile markers 19 and 21, between
mile markers 25 and 30, and between mile markers 34 and 36, and near
mile marker 38.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 4079 7437 4076 7437 4075 7436 4074 7437
      4067 7446 4066 7445 4067 7441 4064 7441
      4060 7463 4062 7467 4087 7438 4082 7434
TIME...MOT...LOC 0549Z 235DEG 35KT 4062 7462 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...<.75 IN

$$

RCM
2 follow-up statements
109 
WWUS51 KPHI 130600
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
200 AM EDT Sun Aug 13 2023

NJC035-130610-
/O.CAN.KPHI.TO.W.0034.000000T0000Z-230813T0615Z/
Somerset NJ-
200 AM EDT Sun Aug 13 2023

...THE TORNADO WARNING FOR NORTHEASTERN SOMERSET COUNTY IS
CANCELLED...
    
The tornadic thunderstorm which prompted the warning has moved out 
of the warned area. Therefore, the warning has been cancelled.

LAT...LON 4079 7437 4076 7438 4075 7436 4067 7446
      4065 7452 4068 7453 4070 7451 4074 7454
      4087 7438 4082 7434
TIME...MOT...LOC 0600Z 235DEG 35KT 4068 7450 

$$

NJC027-130615-
/O.CON.KPHI.TO.W.0034.000000T0000Z-230813T0615Z/
Morris NJ-
200 AM EDT Sun Aug 13 2023

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 215 AM EDT FOR
SOUTHEASTERN MORRIS COUNTY...
    
At 200 AM EDT, a severe thunderstorm capable of producing a tornado
was located over Millington, or near Plainfield, moving northeast at
40 mph.

HAZARD...Tornado.

SOURCE...Radar indicated rotation.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely.

Locations impacted include...
Morristown, Madison, Florham Park, East Hanover, Chatham, Millington
and Hanover Township.

This includes the following highways...
 Interstate 80 in New Jersey between mile markers 45 and 46.
 Interstate 287 in New Jersey near mile marker 31, and between mile
markers 33 and 38.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 4079 7437 4076 7438 4075 7436 4067 7446
      4065 7452 4068 7453 4070 7451 4074 7454
      4087 7438 4082 7434
TIME...MOT...LOC 0600Z 235DEG 35KT 4068 7450 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...<.75 IN

$$

RCM
825 
WWUS51 KPHI 130608
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
208 AM EDT Sun Aug 13 2023

NJC027-130618-
/O.EXP.KPHI.TO.W.0034.000000T0000Z-230813T0615Z/
Morris NJ-
208 AM EDT Sun Aug 13 2023

...THE TORNADO WARNING FOR SOUTHEASTERN MORRIS COUNTY WILL EXPIRE AT
215 AM EDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer appears capable of producing a tornado.
Therefore, the warning will be allowed to expire.

LAT...LON 4079 7437 4076 7438 4075 7436 4067 7446
      4065 7452 4068 7453 4070 7451 4074 7454
      4087 7438 4082 7434
TIME...MOT...LOC 0608Z 235DEG 35KT 4073 7441 

$$

RCM

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 12, 9:22 PM EDTSpecial Weather StatementPHISussex53 min
Aug 13, 1:10 AM EDTSevere Thunderstorm WarningPHIBurlington, Hunterdon, Mercer, Middlesex, Monmouth, Somerset50 min
Aug 13, 1:25 AM EDTTornado WarningPHIHunterdon, Middlesex, Somerset35 min
Aug 13, 1:41 AM EDTSevere Thunderstorm Warning Considerable damage threatPHIHunterdon, Middlesex, Morris, Somerset33 min

Nearby

Tornado Warnings in New Jersey, 2023Every tornado warning in 2023Tornadoes in 2023

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.