Alert archive / New Jersey / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 51, NWS Philadelphia/Mount Holly

July 17, 2018Mercer County, New Jersey

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jul 17, 2018, 2:58 PM EDT for Mercer County, New Jersey. It was in force for 32 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
Jul 17, 2018, 2:58 PM EDT (18:58 UTC)
Expired
Jul 17, 2018, 3:30 PM EDT
In force
32 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

County Mercer County, NJ

The radar

The Philadelphia radar (KDIX), 44 km from the middle of the area, began a volume at 18:58 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 nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 7.0 hours before the alert went out and 169 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 2018-07-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1293 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 2018-07-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 99 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
1293 J/kg
Mixed-layer CIN
-63 J/kg
Mixed-layer LCL
799 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
99 m²/s²
0-3 km storm-relative helicity
113 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

987 
WUUS51 KPHI 171858
SVRPHI
NJC021-171930-
/O.NEW.KPHI.SV.W.0051.180717T1858Z-180717T1930Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
258 PM EDT TUE JUL 17 2018

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Central Mercer County in central New Jersey...

* Until 330 PM EDT.

* At 257 PM EDT, a severe thunderstorm was located over Pennington,
  or near Trenton, moving east at 15 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...
  Trenton, Ewing, Princeton, Pennington, Yardley, Edinburg,
  Mercerville-Hamilton Square, Lawrenceville, Plainsboro Center,
  White Horse, Princeton Junction, Princeton North and
  Yardville-Groveville.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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.

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 4019 7462 4021 7477 4024 7483 4025 7484
      4035 7485 4036 7462 4034 7463 4032 7460
TIME...MOT...LOC 1857Z 271DEG 13KT 4030 7477 

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

MPS
2 follow-up statements
475 
WWUS51 KPHI 171917
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
317 PM EDT TUE JUL 17 2018

NJC021-171930-
/O.CON.KPHI.SV.W.0051.000000T0000Z-180717T1930Z/
Mercer NJ-
317 PM EDT TUE JUL 17 2018

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 330 PM EDT
FOR CENTRAL MERCER COUNTY...

At 316 PM EDT, a severe thunderstorm was located over Lawrenceville,
or near Trenton, moving northeast at 15 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...
Trenton, Ewing, Princeton, Pennington, Mercerville-Hamilton Square,
Edinburg, Lawrenceville, White Horse, Plainsboro Center, Princeton
Junction and Princeton North.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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.

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

&&

LAT...LON 4020 7471 4030 7481 4035 7475 4036 7462
      4034 7463 4032 7460 4021 7462 4020 7467
TIME...MOT...LOC 1916Z 238DEG 11KT 4029 7470 

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

MPS
992 
WWUS51 KPHI 171926
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
326 PM EDT TUE JUL 17 2018

NJC021-171936-
/O.EXP.KPHI.SV.W.0051.000000T0000Z-180717T1930Z/
Mercer NJ-
326 PM EDT TUE JUL 17 2018

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL MERCER COUNTY WILL
EXPIRE AT 330 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.  However gusty winds and heavy rain are still
possible with this thunderstorm.

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

LAT...LON 4020 7471 4030 7481 4035 7475 4036 7462
      4034 7463 4032 7460 4021 7462 4020 7467
TIME...MOT...LOC 1926Z 271DEG 13KT 4029 7467 

$$

MPS

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 17, 3:36 AM EDTFlash Flood WatchPHIBurlington, Camden, Gloucester, Hunterdon, Mercer, Middlesex and 3 more15 hr
Jul 17, 12:35 PM EDTSpecial Weather StatementPHISussex25 min
Jul 17, 1:31 PM EDTSpecial Weather StatementPHIHunterdon44 min
Jul 17, 1:45 PM EDTSpecial Weather StatementPHIMorris30 min
Jul 17, 2:05 PM EDTAreal Flood AdvisoryPHIHunterdon, Morris, Somerset, Sussex, Warren3 hr
Jul 17, 2:09 PM EDTSpecial Weather StatementPHIMorris36 min
Jul 17, 2:44 PM EDTSpecial Weather StatementPHIMiddlesex31 min
Jul 17, 2:48 PM EDTSpecial Weather StatementPHIMercer27 min
Jul 17, 2:50 PM EDTAreal Flood AdvisoryPHIHunterdon, Mercer, Middlesex, Morris, Somerset3 hr
Jul 17, 3:09 PM EDTSpecial Weather StatementPHIMonmouth36 min
Jul 17, 3:48 PM EDTSpecial Weather StatementPHIOcean57 min
Jul 17, 3:51 PM EDTSpecial Weather StatementPHIMonmouth24 min
Jul 17, 3:54 PM EDTSpecial Marine WarningPHI66 min
Jul 17, 3:58 PM EDTSpecial Weather StatementPHIOcean32 min
Jul 17, 4:00 PM EDTSpecial Weather StatementPHICumberland45 min
Jul 17, 4:03 PM EDTAreal Flood AdvisoryPHIBurlington, Mercer, Middlesex, Monmouth, Ocean2 hr
Jul 17, 4:21 PM EDTSpecial Marine WarningPHI24 min
Jul 17, 4:35 PM EDTFlash Flood WarningPHIOcean4 hr
Jul 17, 4:38 PM EDTSpecial Marine WarningPHI52 min
Jul 17, 4:48 PM EDTSpecial Weather StatementPHICumberland, Ocean57 min

Nearby

Severe Thunderstorm Warnings in New Jersey, 2018Every severe thunderstorm warning in 2018

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.