Alert archive / New Jersey / Severe Thunderstorm Warnings in 2023

Severe Thunderstorm Warning 357, NWS Philadelphia/Mount Holly

September 9, 2023Monroe County, Pennsylvania; Sussex County, Warren County, New Jersey

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Sep 9, 2023, 5:18 PM EDT for Monroe County, Pennsylvania; Sussex County, Warren County, New Jersey. It was in force for 45 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: Sep 9, 2023, 5:18 PM EDT (21:18 UTC)
Expired: Sep 9, 2023, 6:03 PM EDT
In force: 45 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Hail: 1.5 in
Wind: 60.0 mph

Counties Sussex County, NJ, Warren County, NJ, Monroe County, PA

The radar

The Philadelphia radar (KDIX), 139 km from the middle of the area, began a volume at 21:21 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
Sep 9, 5:18 PM EDT	TSTM WND DMG	2 Ne Flatbrookville, NJ	Report of two trees down across Walpack Flatbrook Road in Walpack Township. Pictures provided via social media. Time estimated via radar.

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
Sep 9, 4:23 PM EDT	Severe Thunderstorm Watch	SPC	5 hr

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 9.3 hours before the alert went out and 187 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: 1962 J/kg
Mixed-layer CIN: -6 J/kg
Mixed-layer LCL: 541 m above ground
0-6 km bulk shear: 19 kt
0-1 km storm-relative helicity: 55 m²/s²
0-3 km storm-relative helicity: 33 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

450 
WUUS51 KPHI 092118
SVRPHI
NJC037-041-PAC089-092230-
/O.NEW.KPHI.SV.W.0357.230909T2118Z-230909T2230Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
518 PM EDT Sat Sep 9 2023

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  West central Sussex County in northwestern New Jersey...
  Northern Warren County in northwestern New Jersey...
  Northeastern Monroe County in northeastern Pennsylvania...

* Until 630 PM EDT.

* At 518 PM EDT, a severe thunderstorm was located over Blairstown,
  or 13 miles west of Newton, moving north at 15 mph.

  HAZARD...Ping pong ball size hail and 60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...People and animals outdoors will be injured. Expect hail 
           damage to roofs, siding, windows, and vehicles. Wind 
           damage to roofs, siding, trees, and power lines is 
           possible.

* Locations impacted include...
  Blairstown, Flatbrookville, Echo Lake, Werry Lake, Millbrook,
  Delaware Water Gap, Skytop, Marshalls Creek, Hidden Lake and
  Shawnee.

This includes the following highways...
 Interstate 80 in Pennsylvania near mile marker 314.
 Interstate 80 in New Jersey between mile markers 0 and 4.

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 4115 7515 4114 7509 4108 7503 4109 7500
      4115 7490 4096 7486 4093 7510 4096 7512
      4096 7514 4124 7527 4125 7513
TIME...MOT...LOC 2118Z 164DEG 13KT 4102 7501 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.50 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Staarmann

3 follow-up statements

961 
WWUS51 KPHI 092139
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
539 PM EDT Sat Sep 9 2023

NJC037-041-PAC089-092230-
/O.CON.KPHI.SV.W.0357.000000T0000Z-230909T2230Z/
Sussex NJ-Warren NJ-Monroe PA-
539 PM EDT Sat Sep 9 2023

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 630 PM EDT
FOR WESTERN SUSSEX...NORTHWESTERN WARREN AND NORTHEASTERN MONROE
COUNTIES...

At 539 PM EDT, a severe thunderstorm was located over Echo Lake, or
14 miles east of Mount Pocono, moving north at 15 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...
Delaware Water Gap, Flatbrookville, Echo Lake, Werry Lake, Millbrook,
Skytop, Marshalls Creek, Hidden Lake and Shawnee.

This includes Interstate 80 in Pennsylvania near mile marker 314.
 
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 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 4104 7492 4098 7515 4124 7527 4125 7513
      4115 7515 4114 7509 4108 7503 4109 7500
      4114 7492
TIME...MOT...LOC 2139Z 159DEG 13KT 4109 7509 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Staarmann

352 
WWUS51 KPHI 092148
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
548 PM EDT Sat Sep 9 2023

NJC037-041-092158-
/O.CAN.KPHI.SV.W.0357.000000T0000Z-230909T2230Z/
Sussex NJ-Warren NJ-
548 PM EDT Sat Sep 9 2023

...THE SEVERE THUNDERSTORM WARNING FOR WESTERN SUSSEX AND
NORTHWESTERN WARREN COUNTIES IS CANCELLED...
    
The severe thunderstorm which prompted the warning has weakened and 
moved out of the warned area. Therefore, the warning has been 
cancelled.

A Severe Thunderstorm Watch remains in effect until 1100 PM EDT for
northeastern Pennsylvania.

LAT...LON 4105 7518 4124 7527 4125 7513 4115 7515
      4114 7509 4108 7503
TIME...MOT...LOC 2148Z 159DEG 13KT 4111 7516 

$$

PAC089-092230-
/O.CON.KPHI.SV.W.0357.000000T0000Z-230909T2230Z/
Monroe PA-
548 PM EDT Sat Sep 9 2023

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 630 PM EDT
FOR NORTHEASTERN MONROE COUNTY...

At 548 PM EDT, a severe thunderstorm was located near Alpine
Mountain, or 10 miles east of Mount Pocono, moving north at 15 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...
Skytop.

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 4105 7518 4124 7527 4125 7513 4115 7515
      4114 7509 4108 7503
TIME...MOT...LOC 2148Z 159DEG 13KT 4111 7516 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Staarmann

665 
WWUS51 KPHI 092203
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
603 PM EDT Sat Sep 9 2023

PAC089-092213-
/O.CAN.KPHI.SV.W.0357.000000T0000Z-230909T2230Z/
Monroe PA-
603 PM EDT Sat Sep 9 2023

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN MONROE COUNTY IS
CANCELLED...
    
The severe thunderstorm which prompted the warning has weakened and 
moved out of the warned area. Therefore, the warning has been 
cancelled.

A Severe Thunderstorm Watch remains in effect until 1100 PM EDT for
northeastern Pennsylvania.

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

LAT...LON 4105 7518 4124 7527 4125 7513 4115 7515
      4114 7509 4108 7503
TIME...MOT...LOC 2202Z 164DEG 13KT 4116 7518 

$$

Staarmann

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 8, 9:33 PM EDT	Special Weather Statement	PHI	Chester	27 min
Sep 8, 9:48 PM EDT	Severe Thunderstorm Warning	PHI	Chester	42 min
Sep 8, 10:17 PM EDT	Severe Thunderstorm Warning	PHI	Chester, Delaware, Philadelphia	43 min
Sep 8, 10:33 PM EDT	Special Weather Statement	PHI	Berks	27 min
Sep 8, 10:58 PM EDT	Severe Thunderstorm Warning	PHI	Chester, Delaware, Montgomery, Philadelphia	47 min
Sep 8, 11:07 PM EDT	Special Weather Statement	PHI	Carbon	53 min
Sep 9, 3:34 PM EDT	Severe Thunderstorm Warning	PHI	Delaware, Philadelphia	56 min
Sep 9, 4:05 PM EDT	Flash Flood Warning	PHI	Philadelphia	4 hr
Sep 9, 4:15 PM EDT	Special Weather Statement	PHI	Bucks	30 min
Sep 9, 4:29 PM EDT	Special Weather Statement	PHI	Philadelphia	31 min
Sep 9, 4:57 PM EDT	Severe Thunderstorm Warning	PHI	Monroe, Northampton	49 min
Sep 9, 5:36 PM EDT	Special Weather Statement	PHI	Berks	24 min
Sep 9, 5:43 PM EDT	Special Weather Statement	PHI	Lehigh	32 min
Sep 9, 6:38 PM EDT	Special Weather Statement	PHI	Chester	37 min
Sep 9, 7:20 PM EDT	Special Weather Statement	PHI	Chester	25 min
Sep 9, 7:24 PM EDT	Special Weather Statement	PHI	Berks	36 min
Sep 9, 7:25 PM EDT	Special Weather Statement	PHI	Lehigh	35 min
Sep 9, 7:56 PM EDT	Special Weather Statement	PHI	Berks	64 min
Sep 9, 12:56 PM EDT	Severe Thunderstorm Warning	PHI	Atlantic, Burlington, Ocean	64 min
Sep 9, 12:57 PM EDT	Severe Thunderstorm Warning	PHI	Burlington, Ocean	50 min
Sep 9, 1:17 PM EDT	Special Weather Statement	PHI	Ocean	28 min
Sep 9, 1:46 PM EDT	Special Weather Statement	PHI	Ocean	29 min
Sep 9, 2:07 PM EDT	Special Weather Statement	PHI	Atlantic	38 min
Sep 9, 2:16 PM EDT	Special Weather Statement	PHI	Burlington	29 min
Sep 9, 2:26 PM EDT	Special Weather Statement	PHI	Middlesex	34 min
Sep 9, 2:42 PM EDT	Severe Thunderstorm Warning	PHI	Middlesex, Monmouth, Somerset	48 min
Sep 9, 3:09 PM EDT	Severe Thunderstorm Warning Considerable damage threat	PHI	Middlesex, Somerset	49 min
Sep 9, 3:40 PM EDT	Areal Flood Advisory	PHI	Middlesex, Morris, Somerset	2 hr
Sep 9, 3:47 PM EDT	Severe Thunderstorm Warning	PHI	Morris	43 min
Sep 9, 3:58 PM EDT	Special Weather Statement	PHI	Somerset	32 min
Sep 9, 4:08 PM EDT	Severe Thunderstorm Warning	PHI	Morris, Somerset, Sussex	53 min
Sep 9, 4:37 PM EDT	Severe Thunderstorm Warning	PHI	Morris, Sussex, Warren	53 min
Sep 9, 4:40 PM EDT	Special Marine Warning	PHI		65 min
Sep 9, 4:42 PM EDT	Areal Flood Advisory	PHI	Morris	3 hr
Sep 9, 4:49 PM EDT	Special Weather Statement	PHI	Warren	41 min
Sep 9, 5:34 PM EDT	Special Weather Statement	PHI	Salem	26 min

Nearby

Severe Thunderstorm Warnings in New Jersey, 2023 Severe Thunderstorm Warnings in Pennsylvania, 2023 Every severe thunderstorm warning 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.