Alert archive / New Jersey / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 99, NWS Philadelphia/Mount Holly

July 3, 2020Morris County, New Jersey

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 3, 2020, 7:32 PM EDT for Morris County, New Jersey. It was in force for 28 min. 7 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 3, 2020, 7:32 PM EDT (23:32 UTC)
Expired
Jul 3, 2020, 8:00 PM EDT
In force
28 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

County Morris County, NJ

The radar

The Philadelphia radar (KDIX), 106 km from the middle of the area, began a volume at 23:35 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
Jul 3, 7:32 PM EDTTSTM WND DMGBoonton, NJSEVERAL REPORTS OF DOWNED TREES AND WIRES IN BOONTON. TIME ESTIMATED FROM RADAR.
Jul 3, 7:32 PM EDTTSTM WND DMGMountain Lakes, NJDOWNED TREE AND WIRES ON US-46 WESTBOUND AT CR-618. TIME ESTIMATED FROM RADAR.
Jul 3, 7:40 PM EDTTSTM WND DMGPine Brook, NJWIRES DOWNED IN PINE BROOK. TIME ESTIMATED FROM RADAR.
Jul 3, 7:42 PM EDTTSTM WND DMGHanover Twp, NJWIRES DOWNED IN HANOVER. TIME ESTIMATED FROM RADAR.
Jul 3, 7:46 PM EDTTSTM WND DMGMorris Plains, NJNUMEROUS TREES AND WIRES DOWNED IN MORRIS PLAINS. TIME ESTIMATED FROM RADAR.
Jul 3, 7:50 PM EDTTSTM WND DMGFlorham Park, NJWIRES DOWN IN FLORHAM PARK. TIME ESTIMATED FROM RADAR.
Jul 3, 7:50 PM EDTTSTM WND DMGFlorham Park, NJSEVERAL DOWNED POWER LINES IN THE VICINITY OF BRIARWOOD AND RIDGEDALE IN FLORHAM PARK FROM STRONG WINDS. LIGHTNING ALSO DESTROYED A TRANSFORMER. 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 12:00Z, 11.5 hours before the alert went out and 124 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 12:00Z on 2020-07-03Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 42 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 12:00Z on 2020-07-03The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -39 square meters per square second.1939Sfc1 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
42 J/kg
Mixed-layer CIN
-180 J/kg
Mixed-layer LCL
1563 m above ground
0-6 km bulk shear
11 kt
0-1 km storm-relative helicity
-39 m²/s²
0-3 km storm-relative helicity
-27 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

588 
WUUS51 KPHI 032332
SVRPHI
NJC027-040000-
/O.NEW.KPHI.SV.W.0099.200703T2332Z-200704T0000Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
732 PM EDT Fri Jul 3 2020

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Northeastern Morris County in northern New Jersey...

* Until 800 PM EDT.

* At 732 PM EDT, a severe thunderstorm was located over Boonton, or
  near Caldwell, moving southeast at 25 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...
  Florham Park, East Hanover, Lincoln Park, Kinnelon, Boonton,
  Butler, Rockaway, Morris Plains, Mountain Lakes, Riverdale, Victory
  Gardens, Parsippany, Pequannock Township, Hanover Township and
  White Meadow Lake.

This includes the following highways...
 Interstate 80 in New Jersey between mile markers 38 and 48.
 Interstate 287 in New Jersey between mile markers 38 and 54.

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 this storm. Move indoors
immediately. 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 4091 7433 4088 7434 4086 7432 4082 7434
      4079 7437 4076 7437 4087 7455 4102 7441
      4100 7430 4097 7428 4092 7429 4091 7427
      4090 7427
TIME...MOT...LOC 2332Z 300DEG 20KT 4090 7439 

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

CMS
2 follow-up statements
168 
WWUS51 KPHI 032347
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
747 PM EDT Fri Jul 3 2020

NJC027-040000-
/O.CON.KPHI.SV.W.0099.000000T0000Z-200704T0000Z/
Morris NJ-
747 PM EDT Fri Jul 3 2020

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 800 PM EDT
FOR EAST CENTRAL MORRIS COUNTY...

At 746 PM EDT, a severe thunderstorm was located over East Hanover,
or near Caldwell, moving southeast at 25 mph.

HAZARD...70 mph wind gusts and penny size hail.

SOURCE...Radar indicated.

IMPACT...Expect considerable tree damage. Damage is likely to mobile 
         homes, roofs, and outbuildings.

Locations impacted include...
Florham Park, East Hanover, Lincoln Park, Boonton, Morris Plains,
Mountain Lakes, Parsippany and Hanover Township.

This includes the following highways...
 Interstate 80 in New Jersey between mile markers 40 and 48.
 Interstate 287 in New Jersey between mile markers 38 and 49.

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 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 4091 7433 4088 7434 4086 7432 4082 7434
      4079 7437 4076 7437 4087 7455 4097 7428
      4092 7429 4091 7427 4090 7427
TIME...MOT...LOC 2346Z 328DEG 20KT 4081 7436 

HAIL...0.75IN
WIND...70MPH
 
$$

CMS
876 
WWUS51 KPHI 032358
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
758 PM EDT Fri Jul 3 2020

NJC027-040007-
/O.EXP.KPHI.SV.W.0099.000000T0000Z-200704T0000Z/
Morris NJ-
758 PM EDT Fri Jul 3 2020

...THE SEVERE THUNDERSTORM WARNING FOR EAST CENTRAL MORRIS COUNTY
WILL EXPIRE AT 800 PM EDT...
        
The storm which prompted the warning has moved out of the area.
Therefore, the warning will be allowed to expire.

Remember, a Severe Thunderstorm Warning still remains in effect for 
southeastern Morris County until 815 pm. This storm produced 
widespread wind damage in eastern Morris County.

LAT...LON 4091 7433 4088 7434 4086 7432 4082 7434
      4079 7437 4076 7437 4087 7455 4097 7428
      4092 7429 4091 7427 4090 7427
TIME...MOT...LOC 2357Z 300DEG 20KT 4078 7430 

$$

CMS

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 3, 12:19 PM EDTCoastal Flood AdvisoryPHIAtlantic, Burlington, Cape May, Cumberland, Middlesex, Monmouth and 1 more12 hr
Jul 3, 6:35 PM EDTSevere Thunderstorm WarningPHISussex40 min
Jul 3, 7:19 PM EDTSpecial Weather StatementPHIMorris26 min
Jul 3, 7:30 PM EDTAreal Flood AdvisoryPHIMorris, Sussex105 min
Jul 3, 7:41 PM EDTSevere Thunderstorm WarningPHIMorris, Somerset34 min
Jul 3, 7:45 PM EDTSpecial Weather StatementPHIHunterdon, Somerset30 min

Nearby

Severe Thunderstorm Warnings in New Jersey, 2020Every 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.