Alert archive / New Jersey / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 168, NWS Philadelphia/Mount Holly

August 18, 2017Hunterdon County, Morris County, Somerset County, New Jersey

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 18, 2017, 5:46 PM EDT for Hunterdon County, Morris County, Somerset County, New Jersey. It was in force for 44 min. 1 report 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 18, 2017, 5:46 PM EDT (21:46 UTC)
Expired: Aug 18, 2017, 6:30 PM EDT
In force: 44 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Tornado: Possible
Hail: 0.88 in
Wind: 60.0 mph

Counties Hunterdon County, NJ, Morris County, NJ, Somerset County, NJ

The radar

The Philadelphia radar (KDIX), 82 km from the middle of the area, began a volume at 21:49 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
Aug 18, 6:06 PM EDT	TSTM WND DMG	Readington Twp, NJ	DOWNED TREES AND WIRES IN THE TOWNSHIP.

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
Aug 18, 2:27 PM EDT	Severe Thunderstorm Watch	SPC	9 hr

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 9.8 hours before the alert went out and 145 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1073 m above ground
0-6 km bulk shear: 30 kt
0-1 km storm-relative helicity: 147 m²/s²
0-3 km storm-relative helicity: 215 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.6

Open this sounding in Storm Lab

The text

As transmitted.

260 
WUUS51 KPHI 182146
SVRPHI
NJC019-027-035-182230-
/O.NEW.KPHI.SV.W.0168.170818T2146Z-170818T2230Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
546 PM EDT FRI AUG 18 2017

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Southern Morris County in northern New Jersey...
  Northeastern Hunterdon County in northwestern New Jersey...
  Northern Somerset County in northern New Jersey...

* Until 630 PM EDT

* At 546 PM EDT, a severe thunderstorm was located over Annandale, or
  14 miles northwest of Somerville, moving east at 25 mph.

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

  SOURCE...Radar indicated. 

  IMPACT...Expect damage to trees and power lines. 

* Locations impacted include...
  Morristown, Somerville, Bridgewater, Madison, Chatham, Morris
  Plains, Mendham, High Bridge, Clinton, Peapack And Gladstone, Glen
  Gardner, Chester, Hampton, Lebanon, Califon, Far Hills,
  Martinsville, Millington, Annandale and White House Station.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain alert for a possible tornado! Tornadoes can develop quickly
from severe thunderstorms. If you spot a tornado go at once into the
basement or small central room in a sturdy structure.

To report severe weather, contact your nearest law enforcement
agency. They will send your report to the National Weather Service
office in Mount Holly NJ.

&&

LAT...LON 4068 7445 4067 7446 4066 7445 4066 7441
      4063 7442 4059 7448 4054 7493 4071 7498
      4073 7496 4086 7442 4072 7438
TIME...MOT...LOC 2146Z 257DEG 22KT 4065 7487 

TORNADO...POSSIBLE
HAIL...0.88IN
WIND...60MPH
 
$$

SFJ

2 follow-up statements

375 
WWUS51 KPHI 182207
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
607 PM EDT FRI AUG 18 2017

NJC019-027-035-182230-
/O.CON.KPHI.SV.W.0168.000000T0000Z-170818T2230Z/
Morris NJ-Hunterdon NJ-Somerset NJ-
607 PM EDT FRI AUG 18 2017

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 630 PM EDT
FOR SOUTHERN MORRIS...NORTHEASTERN HUNTERDON AND NORTHERN SOMERSET
COUNTIES...

At 606 PM EDT, a severe thunderstorm was located near Peapack And
Gladstone, or 9 miles northwest of Somerville, moving east at 25 mph.

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

SOURCE...Radar indicated. 

IMPACT...Expect damage to trees and power lines. 

Locations impacted include...
Morristown, Somerville, Bridgewater, Madison, Chatham, Morris Plains,
Mendham, Peapack And Gladstone, Chester, Lebanon, Califon, Far Hills,
Martinsville, Millington, White House Station, Basking Ridge,
Parsippany, Long Valley, North Plainfield and Bernardsville.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain alert for a possible tornado! Tornadoes can develop quickly
from severe thunderstorms. If you spot a tornado go at once into the
basement or small central room in a sturdy structure.

To report severe weather contact your nearest law enforcement agency.
They will send your report to the National Weather Service office in
Mount Holly NJ.

&&

LAT...LON 4068 7445 4067 7446 4066 7445 4066 7441
      4063 7442 4059 7448 4055 7482 4076 7484
      4086 7442 4072 7438
TIME...MOT...LOC 2206Z 257DEG 22KT 4068 7471 

TORNADO...POSSIBLE
HAIL...0.88IN
WIND...60MPH
 
$$

SFJ

147 
WWUS51 KPHI 182224
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
624 PM EDT FRI AUG 18 2017

NJC019-027-035-182233-
/O.EXP.KPHI.SV.W.0168.000000T0000Z-170818T2230Z/
Morris NJ-Hunterdon NJ-Somerset NJ-
624 PM EDT FRI AUG 18 2017

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHERN MORRIS...NORTHEASTERN
HUNTERDON AND NORTHERN SOMERSET COUNTIES WILL EXPIRE AT 630 PM EDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore the warning will be allowed to expire.  However gusty winds
are still possible with this thunderstorm.

A severe thunderstorm watch remains in effect until 900 PM EDT for
northern and northwestern New Jersey.


LAT...LON 4068 7445 4067 7446 4066 7445 4066 7441
      4063 7442 4059 7448 4055 7482 4076 7484
      4086 7442 4072 7438
TIME...MOT...LOC 2223Z 257DEG 22KT 4070 7459 

$$

SFJ

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 18, 3:39 AM EDT	Flash Flood Watch	PHI	Atlantic, Burlington, Camden, Cape May, Cumberland, Gloucester and 10 more	18 hr
Aug 18, 3:41 AM EDT	Small Craft Advisory	PHI		18 hr
Aug 18, 10:51 AM EDT	Special Weather Statement	PHI	Ocean	54 min
Aug 18, 11:19 AM EDT	Areal Flood Advisory	PHI	Burlington, Ocean	116 min
Aug 18, 11:28 AM EDT	Special Weather Statement	PHI	Ocean	47 min
Aug 18, 5:08 PM EDT	Special Weather Statement	PHI	Hunterdon, Warren	37 min
Aug 18, 5:11 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Mercer, Somerset	49 min
Aug 18, 5:20 PM EDT	Areal Flood Advisory	PHI	Burlington, Camden, Gloucester, Mercer, Salem	3 hr
Aug 18, 5:39 PM EDT	Severe Thunderstorm Warning	PHI	Burlington, Camden, Gloucester, Salem	66 min
Aug 18, 5:42 PM EDT	Special Weather Statement	PHI	Hunterdon	33 min
Aug 18, 5:50 PM EDT	Special Marine Warning	PHI		55 min
Aug 18, 5:54 PM EDT	Severe Thunderstorm Warning	PHI	Burlington, Mercer, Middlesex, Monmouth	66 min
Aug 18, 6:13 PM EDT	Special Weather Statement	PHI	Middlesex, Somerset	32 min
Aug 18, 6:20 PM EDT	Areal Flood Advisory	PHI	Middlesex, Somerset	3 hr
Aug 18, 6:23 PM EDT	Special Weather Statement	PHI	Somerset	37 min
Aug 18, 6:38 PM EDT	Special Weather Statement	PHI	Camden, Gloucester, Salem	37 min
Aug 18, 6:41 PM EDT	Special Marine Warning	PHI		64 min
Aug 18, 6:43 PM EDT	Areal Flood Advisory	PHI	Monmouth, Ocean	3 hr
Aug 18, 6:48 PM EDT	Special Weather Statement	PHI	Cumberland, Gloucester, Salem	27 min
Aug 18, 6:53 PM EDT	Special Weather Statement	PHI	Middlesex, Monmouth	52 min
Aug 18, 6:54 PM EDT	Special Weather Statement	PHI	Burlington, Camden, Gloucester	51 min
Aug 18, 6:58 PM EDT	Severe Thunderstorm Warning	PHI	Burlington, Camden, Ocean	29 min
Aug 18, 7:00 PM EDT	Severe Thunderstorm Warning	PHI	Burlington, Mercer, Middlesex, Monmouth, Ocean	60 min
Aug 18, 7:19 PM EDT	Areal Flood Advisory	PHI	Atlantic, Burlington, Cape May, Cumberland, Ocean, Salem	3 hr
Aug 18, 7:25 PM EDT	Special Weather Statement	PHI	Atlantic	50 min
Aug 18, 7:34 PM EDT	Special Weather Statement	PHI	Cape May	26 min
Aug 18, 7:39 PM EDT	Special Marine Warning	PHI		66 min
Aug 18, 7:43 PM EDT	Special Weather Statement	PHI	Burlington, Ocean	47 min
Aug 18, 7:44 PM EDT	Special Marine Warning	PHI		61 min
Aug 18, 7:49 PM EDT	Severe Thunderstorm Warning	PHI	Atlantic, Cape May, Cumberland, Gloucester	35 min

Nearby

Severe Thunderstorm Warnings in New Jersey, 2017 Every severe thunderstorm warning in 2017

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.