Alert archive / New Jersey / Severe Thunderstorm Warnings in 2024

Severe Thunderstorm Warning 211, NWS Philadelphia/Mount Holly

August 18, 2024Bucks County, Pennsylvania; 4 counties in New Jersey

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 18, 2024, 5:47 PM EDT for Bucks County, Pennsylvania; 4 counties in New Jersey. It was in force for 58 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 18, 2024, 5:47 PM EDT (21:47 UTC)
Expired
Aug 18, 2024, 6:45 PM EDT
In force
58 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Burlington County, NJ, Mercer County, NJ, Middlesex County, NJ, Monmouth County, NJ, Bucks County, PA

The radar

The Philadelphia radar (KDIX), 39 km from the middle of the area, began a volume at 21:48 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.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Aug 18, 2:02 PM EDTSevere Thunderstorm WatchSPC8 hr

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 9.8 hours before the alert went out and 170 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 2024-08-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 109 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 2024-08-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 187 square meters per square second.193958Sfc1 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
109 J/kg
Mixed-layer CIN
-20 J/kg
Mixed-layer LCL
582 m above ground
0-6 km bulk shear
26 kt
0-1 km storm-relative helicity
187 m²/s²
0-3 km storm-relative helicity
205 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

Open this sounding in Storm Lab

The text

As transmitted.

376 
WUUS51 KPHI 182147 RRA
SVRPHI
NJC005-021-023-025-PAC017-182245-
/O.NEW.KPHI.SV.W.0211.240818T2147Z-240818T2245Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
547 PM EDT Sun Aug 18 2024

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Mercer County in central New Jersey...
  North central Burlington County in southern New Jersey...
  Southwestern Monmouth County in central New Jersey...
  Southwestern Middlesex County in northern New Jersey...
  Southeastern Bucks County in southeastern Pennsylvania...

* Until 645 PM EDT.

* At 547 PM EDT, a severe thunderstorm was located over Jacksonville,
  or 12 miles south of Trenton, moving northeast at 25 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...
  Trenton, Manalapan, Ewing, Lumberton, Princeton, Florence,
  Burlington, Bristol, Mount Holly, Hightstown, Bordentown, Cranbury,
  Tullytown, Allentown, Pemberton, Roosevelt, Wrightstown, Princeton
  Meadows, Windsor, and Florence-Roebling.

This includes the following highways...
 New Jersey Turnpike between exits 5 and 8A.
 Pennsylvania Turnpike near mile marker 359.
 Interstate 195 in New Jersey between mile markers 0 and 15.
 Interstate 295 in New Jersey between mile markers 44 and 72.

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 3993 7475 4000 7489 4040 7474 4039 7473
      4037 7472 4038 7469 4039 7465 4026 7432
TIME...MOT...LOC 2147Z 210DEG 22KT 4005 7480 

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

$$

Staarmann
3 follow-up statements
086 
WWUS51 KPHI 182158
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
558 PM EDT Sun Aug 18 2024

NJC005-021-023-025-PAC017-182245-
/O.CON.KPHI.SV.W.0211.000000T0000Z-240818T2245Z/
Mercer NJ-Burlington NJ-Monmouth NJ-Middlesex NJ-Bucks PA-
558 PM EDT Sun Aug 18 2024

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 645 PM EDT
FOR MERCER...NORTH CENTRAL BURLINGTON...SOUTHWESTERN MONMOUTH...
SOUTHWESTERN MIDDLESEX AND EASTERN BUCKS COUNTIES...

At 558 PM EDT, a severe thunderstorm was located over Columbus, or 8
miles southeast of Trenton, moving northeast at 25 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...
Trenton, Manalapan, Ewing, Princeton, Florence, Burlington,
Hightstown, Bordentown, Cranbury, Tullytown, Allentown, Roosevelt,
Wrightstown, Princeton Meadows, Windsor, Florence-Roebling, Kingston,
Plainsboro Center, Jacksonville, and Georgetown.

This includes the following highways...
 New Jersey Turnpike between exits 6 and 8A.
 Interstate 195 in New Jersey between mile markers 0 and 15.
 Interstate 295 in New Jersey between mile markers 49 and 71.

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 4000 7466 4006 7484 4040 7474 4039 7473
      4037 7472 4038 7469 4039 7465 4026 7432
TIME...MOT...LOC 2158Z 212DEG 22KT 4010 7470 

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

$$

Staarmann
921 
WWUS51 KPHI 182221
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
621 PM EDT Sun Aug 18 2024

PAC017-182231-
/O.CAN.KPHI.SV.W.0211.000000T0000Z-240818T2245Z/
Bucks PA-
621 PM EDT Sun Aug 18 2024

...THE SEVERE THUNDERSTORM WARNING FOR EASTERN BUCKS COUNTY IS
CANCELLED...

The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

A Severe Thunderstorm Watch remains in effect until 1000 PM EDT for
southern, central and northern New Jersey...and southeastern
Pennsylvania.

LAT...LON 4010 7464 4014 7473 4016 7472 4018 7475
      4034 7476 4040 7474 4037 7472 4039 7465
      4027 7435
TIME...MOT...LOC 2221Z 208DEG 21KT 4021 7464 

$$

NJC005-021-023-025-182245-
/O.CON.KPHI.SV.W.0211.000000T0000Z-240818T2245Z/
Mercer NJ-Burlington NJ-Monmouth NJ-Middlesex NJ-
621 PM EDT Sun Aug 18 2024

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 645 PM EDT
FOR MERCER...NORTHERN BURLINGTON...WEST CENTRAL MONMOUTH AND
SOUTHWESTERN MIDDLESEX COUNTIES...

At 621 PM EDT, a severe thunderstorm was located over
Mercerville-Hamilton Square, or near Trenton, moving northeast at 25
mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Damage to roofs, siding, trees, and power lines is 
         possible.

Locations impacted include...
Trenton, Manalapan, Ewing, Princeton, Hightstown, Bordentown,
Cranbury, Allentown, Roosevelt, Princeton Meadows, Windsor,
Plainsboro Center, Clearbrook Park, Edinburg, Crosswicks, White
Horse, Twin Rivers, Mercerville-Hamilton Square, Lawrenceville, and
Kingston.

This includes the following highways...
 New Jersey Turnpike between exits 8 and 8A.
 Interstate 195 in New Jersey between mile markers 0 and 11.
 Interstate 295 in New Jersey between mile markers 57 and 70.

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 4010 7464 4014 7473 4016 7472 4018 7475
      4034 7476 4040 7474 4037 7472 4039 7465
      4027 7435
TIME...MOT...LOC 2221Z 208DEG 21KT 4021 7464 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Staarmann
857 
WWUS51 KPHI 182237
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
637 PM EDT Sun Aug 18 2024

NJC005-021-023-025-182247-
/O.EXP.KPHI.SV.W.0211.000000T0000Z-240818T2245Z/
Mercer NJ-Burlington NJ-Monmouth NJ-Middlesex NJ-
637 PM EDT Sun Aug 18 2024

...THE SEVERE THUNDERSTORM WARNING FOR MERCER...NORTHERN
BURLINGTON...WEST CENTRAL MONMOUTH AND SOUTHWESTERN MIDDLESEX
COUNTIES WILL EXPIRE AT 645 PM EDT...

The storm which prompted the warning has weakened below severe
limits, and has exited the warned area. Therefore, the warning will
be allowed to expire.

A Severe Thunderstorm Watch remains in effect until 1000 PM EDT for
southern, central and northern New Jersey...and southeastern
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 4010 7464 4014 7473 4016 7472 4018 7475
      4034 7476 4040 7474 4037 7472 4039 7465
      4027 7435
TIME...MOT...LOC 2237Z 210DEG 22KT 4028 7459 

$$

Staarmann

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 18, 1:35 AM EDTFlash Flood WarningPHIBucks, Delaware, Montgomery, Philadelphia2 hr
Aug 18, 3:09 AM EDTFlash Flood WarningPHIBucks93 min
Aug 18, 3:24 PM EDTSevere Thunderstorm WarningPHIMonroe, Northampton19 min
Aug 18, 3:34 PM EDTSevere Thunderstorm WarningPHIChester, Delaware, Montgomery, Philadelphia41 min
Aug 18, 3:48 PM EDTSevere Thunderstorm WarningPHICarbon, Monroe42 min
Aug 18, 4:04 PM EDTSevere Thunderstorm WarningPHIMonroe41 min
Aug 18, 4:25 PM EDTSevere Thunderstorm WarningPHIBucks, Lehigh, Montgomery, Northampton28 min
Aug 18, 4:41 PM EDTSevere Thunderstorm WarningPHIMonroe, Northampton34 min
Aug 18, 4:56 PM EDTFlash Flood WarningPHIMonroe, Northampton6 hr
Aug 18, 5:21 PM EDTSevere Thunderstorm WarningPHIBucks39 min
Aug 18, 5:31 PM EDTFlash Flood WarningPHIBucks, Lehigh, Northampton6 hr
Aug 18, 4:41 AM EDTFlash Flood WarningPHIBurlington, Camden, Mercer2 hr
Aug 18, 2:17 PM EDTSpecial Marine WarningPHI58 min
Aug 18, 2:42 PM EDTSpecial Marine WarningPHI93 min
Aug 18, 3:55 PM EDTSpecial Marine WarningPHI95 min
Aug 18, 5:10 PM EDTSevere Thunderstorm WarningPHIHunterdon, Morris, Warren29 min
Aug 18, 5:38 PM EDTFlash Flood WarningPHISussex, Warren4 hr
Aug 18, 5:47 PM EDTSevere Thunderstorm WarningPHIMorris, Sussex43 min
Aug 18, 5:51 PM EDTSevere Thunderstorm WarningPHIMorris, Somerset24 min
Aug 18, 5:59 PM EDTSevere Thunderstorm WarningPHIMorris, Sussex18 min
Aug 18, 6:01 PM EDTFlash Flood WarningPHIHunterdon, Morris, Somerset, Sussex, Warren6 hr
Aug 18, 6:24 PM EDTSevere Thunderstorm WarningPHIMiddlesex, Morris, Somerset66 min
Aug 18, 6:36 PM EDTFlash Flood WarningPHIMorris, Somerset5 hr

Nearby

Severe Thunderstorm Warnings in New Jersey, 2024Severe Thunderstorm Warnings in Pennsylvania, 2024Every severe thunderstorm warning in 2024

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.