Alert archive / New Jersey / Severe Thunderstorm Warnings in 2019

Severe Thunderstorm Warning 357, NWS Philadelphia/Mount Holly

August 18, 2019Hunterdon County, Somerset County, New Jersey; Bucks County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 18, 2019, 5:36 PM EDT for Hunterdon County, Somerset County, New Jersey; Bucks County, Pennsylvania. It was in force for 39 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, 2019, 5:36 PM EDT (21:36 UTC)
Expired: Aug 18, 2019, 6:15 PM EDT
In force: 39 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Hunterdon County, NJ, Somerset County, NJ, Bucks County, PA

The radar

The Philadelphia radar (KDIX), 79 km from the middle of the area, began a volume at 21:38 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, 5:36 PM EDT	TSTM WND DMG	1 Ese Frenchtown, NJ	BARN AWNING/ROOF BLOWN OFF. SOME MINOR TREE DAMAGE NEARBY AS WELL. 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, 9.6 hours before the alert went out and 179 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: 1275 J/kg
Mixed-layer CIN: -19 J/kg
Mixed-layer LCL: 622 m above ground
0-6 km bulk shear: 28 kt
0-1 km storm-relative helicity: 50 m²/s²
0-3 km storm-relative helicity: 70 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.0

Open this sounding in Storm Lab

The text

As transmitted.

511 
WUUS51 KPHI 182136
SVRPHI
NJC019-035-PAC017-182215-
/O.NEW.KPHI.SV.W.0357.190818T2136Z-190818T2215Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
536 PM EDT Sun Aug 18 2019

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Central Hunterdon County in northwestern New Jersey...
  West central Somerset County in northern New Jersey...
  North central Bucks County in southeastern Pennsylvania...

* Until 615 PM EDT.

* At 536 PM EDT, a severe thunderstorm was located near Frenchtown,
  or 16 miles southeast of Easton, moving northeast at 10 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...
  Flemington, Clinton, Frenchtown, Lebanon, Milford, Erwinna,
  Annandale and White House Station.

This includes Interstate 78 in New Jersey between mile markers 16 and
24.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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 4046 7506 4055 7511 4070 7479 4050 7468
TIME...MOT...LOC 2136Z 246DEG 8KT 4053 7499 

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

Staarmann

2 follow-up statements

559 
WWUS51 KPHI 182200
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
600 PM EDT Sun Aug 18 2019

NJC035-182210-
/O.CAN.KPHI.SV.W.0357.000000T0000Z-190818T2215Z/
Somerset NJ-
600 PM EDT Sun Aug 18 2019

...THE SEVERE THUNDERSTORM WARNING FOR WEST CENTRAL SOMERSET COUNTY
IS CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

LAT...LON 4055 7474 4051 7477 4052 7479 4051 7480
      4049 7478 4046 7506 4055 7511 4070 7479
      4057 7472
TIME...MOT...LOC 2200Z 230DEG 3KT 4054 7499 

$$

NJC019-PAC017-182215-
/O.CON.KPHI.SV.W.0357.000000T0000Z-190818T2215Z/
Hunterdon NJ-Bucks PA-
600 PM EDT Sun Aug 18 2019

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 615 PM EDT
FOR CENTRAL HUNTERDON AND NORTH CENTRAL BUCKS COUNTIES...

At 600 PM EDT, a severe thunderstorm was located near Frenchtown, or
15 miles southeast of Easton, and is nearly stationary.

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...
Flemington, Clinton, Frenchtown, Lebanon, Milford, Erwinna, Annandale
and White House Station.

This includes Interstate 78 in New Jersey between mile markers 16 and
24.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 4055 7474 4051 7477 4052 7479 4051 7480
      4049 7478 4046 7506 4055 7511 4070 7479
      4057 7472
TIME...MOT...LOC 2200Z 230DEG 3KT 4054 7499 

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

Staarmann

702 
WWUS51 KPHI 182212
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
612 PM EDT Sun Aug 18 2019

NJC019-PAC017-182222-
/O.EXP.KPHI.SV.W.0357.000000T0000Z-190818T2215Z/
Hunterdon NJ-Bucks PA-
612 PM EDT Sun Aug 18 2019

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL HUNTERDON AND NORTH
CENTRAL BUCKS COUNTIES WILL EXPIRE AT 615 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 small 
hail, gusty winds, and heavy rain are still possible with this 
thunderstorm.

LAT...LON 4055 7474 4051 7477 4052 7479 4051 7480
      4049 7478 4046 7506 4055 7511 4070 7479
      4057 7472
TIME...MOT...LOC 2212Z 246DEG 8KT 4055 7497 

$$

Staarmann

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 17, 10:37 PM EDT	Special Weather Statement	PHI	Morris	23 min
Aug 17, 10:50 PM EDT	Special Weather Statement	PHI	Morris	25 min
Aug 17, 11:19 PM EDT	Special Weather Statement	PHI	Morris	26 min
Aug 18, 3:32 AM EDT	Heat Advisory	PHI	Burlington, Camden, Gloucester, Hunterdon, Mercer, Middlesex and 5 more	4 days
Aug 18, 3:03 PM EDT	Special Weather Statement	PHI	Burlington	27 min
Aug 18, 3:15 PM EDT	Special Weather Statement	PHI	Burlington	30 min
Aug 18, 3:21 PM EDT	Severe Thunderstorm Warning	PHI	Burlington, Ocean	39 min
Aug 18, 3:35 PM EDT	Special Weather Statement	PHI	Burlington	25 min
Aug 18, 4:48 PM EDT	Special Weather Statement	PHI	Somerset	27 min
Aug 18, 4:49 PM EDT	Special Weather Statement	PHI	Warren	26 min
Aug 18, 5:01 PM EDT	Special Weather Statement	PHI	Monmouth	29 min
Aug 18, 5:05 PM EDT	Special Weather Statement	PHI	Hunterdon	25 min
Aug 18, 5:18 PM EDT	Special Weather Statement	PHI	Somerset	27 min
Aug 18, 5:29 PM EDT	Areal Flood Advisory	PHI	Hunterdon, Middlesex, Morris, Somerset, Warren	2 hr
Aug 18, 5:32 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Middlesex, Morris, Somerset	43 min
Aug 18, 5:46 PM EDT	Special Weather Statement	PHI	Warren	44 min
Aug 18, 5:57 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Morris, Warren	48 min
Aug 18, 6:28 PM EDT	Special Weather Statement	PHI	Hunterdon, Morris, Sussex, Warren	47 min
Aug 18, 6:40 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Morris, Somerset, Sussex, Warren	54 min
Aug 18, 7:09 PM EDT	Areal Flood Advisory	PHI	Morris, Sussex, Warren	3 hr
Aug 17, 8:32 PM EDT	Special Weather Statement	PHI	Carbon, Monroe	73 min
Aug 18, 4:22 PM EDT	Special Weather Statement	PHI	Berks	38 min
Aug 18, 4:34 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Montgomery	41 min
Aug 18, 4:36 PM EDT	Special Weather Statement	PHI	Bucks	24 min
Aug 18, 5:01 PM EDT	Areal Flood Advisory	PHI	Berks, Montgomery	3 hr
Aug 18, 5:16 PM EDT	Special Weather Statement	PHI	Berks	29 min
Aug 18, 5:25 PM EDT	Special Weather Statement	PHI	Carbon, Monroe, Northampton	65 min
Aug 18, 5:38 PM EDT	Severe Thunderstorm Warning	PHI	Bucks, Lehigh, Northampton	52 min
Aug 18, 5:42 PM EDT	Special Weather Statement	PHI	Berks	48 min
Aug 18, 7:03 PM EDT	Special Weather Statement	PHI	Berks	27 min
Aug 18, 7:23 PM EDT	Special Weather Statement	PHI	Berks	67 min

Nearby

Severe Thunderstorm Warnings in New Jersey, 2019 Severe Thunderstorm Warnings in Pennsylvania, 2019 Every severe thunderstorm warning in 2019

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.