Alert archive / New Jersey / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 26, NWS Philadelphia/Mount Holly

April 29, 20176 counties in New Jersey; Bucks County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Apr 29, 2017, 4:32 AM EDT for 6 counties in New Jersey; Bucks County, Pennsylvania. It was in force for 43 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
Apr 29, 2017, 4:32 AM EDT (08:32 UTC)
Expired
Apr 29, 2017, 5:15 AM EDT
In force
43 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Hunterdon County, NJ, Mercer County, NJ, Middlesex County, NJ, Monmouth County, NJ, Morris County, NJ, Somerset County, NJ, Bucks County, PA

The radar

The Philadelphia radar (KDIX), 71 km from the middle of the area, began a volume at 08:31 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 00:00Z, 8.5 hours before the alert went out and 131 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 00:00Z on 2017-04-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 00:00Z on 2017-04-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 215 square meters per square second.19395878Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1920 m above ground
0-6 km bulk shear
53 kt
0-1 km storm-relative helicity
215 m²/s²
0-3 km storm-relative helicity
229 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

545 
WUUS51 KPHI 290832
SVRPHI
NJC019-021-023-025-027-035-PAC017-290915-
/O.NEW.KPHI.SV.W.0026.170429T0832Z-170429T0915Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
432 AM EDT SAT APR 29 2017

The National Weather Service in Mount Holly NJ  has issued a

* Severe Thunderstorm Warning for...
  Southeastern Morris County in northern New Jersey...
  Hunterdon County in northwestern New Jersey...
  Northwestern Mercer County in central New Jersey...
  Somerset County in northern New Jersey...
  Northeastern Monmouth County in central New Jersey...
  Middlesex County in northern New Jersey...
  Central Bucks County in southeastern Pennsylvania...

* Until 515 AM EDT

* At 432 AM EDT, a severe thunderstorm was located over Cloverhill,
  or 12 miles southwest of Somerville, moving east at 55 mph.

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

  SOURCE...Radar indicated. 

  IMPACT...Hail damage to vehicles is expected. Expect wind damage 
           to roofs, siding, and trees. 

* Locations impacted include...
  New Brunswick, Perth Amboy, Morristown, Somerville, Sandy Hook,
  Somerset, Edison, Old Bridge, East Brunswick, Bridgewater, South
  Brunswick, Sayreville, North Brunswick, Carteret, Madison,
  Middlesex, Princeton, Florham Park, East Hanover and Bound Brook.

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 4028 7501 4053 7511 4091 7431 4089 7434
      4086 7433 4079 7437 4075 7436 4067 7446
      4065 7441 4060 7446 4060 7421 4056 7421
      4055 7425 4050 7428 4046 7426 4044 7410
      4046 7401 4047 7401 4044 7398
TIME...MOT...LOC 0832Z 257DEG 49KT 4045 7480 

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

SFJ
2 follow-up statements
540 
WWUS51 KPHI 290857
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
457 AM EDT SAT APR 29 2017

PAC017-290906-
/O.CAN.KPHI.SV.W.0026.000000T0000Z-170429T0915Z/
Bucks PA-
457 AM EDT SAT APR 29 2017

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL BUCKS 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 4031 7485 4070 7476 4091 7431 4089 7434
      4086 7433 4079 7437 4075 7436 4067 7446
      4065 7441 4060 7446 4060 7421 4056 7421
      4055 7425 4050 7428 4046 7426 4044 7410
      4046 7401 4047 7401 4044 7398
TIME...MOT...LOC 0856Z 257DEG 49KT 4053 7437 

$$

NJC019-021-023-025-027-035-290915-
/O.CON.KPHI.SV.W.0026.000000T0000Z-170429T0915Z/
Morris NJ-Hunterdon NJ-Mercer NJ-Somerset NJ-Monmouth NJ-
Middlesex NJ-
457 AM EDT SAT APR 29 2017

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 515 AM EDT
FOR SOUTHEASTERN MORRIS...SOUTHEASTERN HUNTERDON...NORTHWESTERN
MERCER...SOMERSET...NORTHEASTERN MONMOUTH AND MIDDLESEX COUNTIES...

At 456 AM EDT, a severe thunderstorm was located over Edison, or near
New Brunswick, moving east at 55 mph.

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

SOURCE...Radar indicated. 

IMPACT...Hail damage to vehicles is expected. Expect wind damage to 
         roofs, siding, and trees. 

Locations impacted include...
New Brunswick, Perth Amboy, Morristown, Somerville, Sandy Hook,
Somerset, Edison, Old Bridge, East Brunswick, Bridgewater, South
Brunswick, Sayreville, North Brunswick, Carteret, Madison, Middlesex,
Princeton, Florham Park, East Hanover and Bound Brook.

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 4031 7485 4070 7476 4091 7431 4089 7434
      4086 7433 4079 7437 4075 7436 4067 7446
      4065 7441 4060 7446 4060 7421 4056 7421
      4055 7425 4050 7428 4046 7426 4044 7410
      4046 7401 4047 7401 4044 7398
TIME...MOT...LOC 0856Z 257DEG 49KT 4053 7437 

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

SFJ
339 
WWUS51 KPHI 290907
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
507 AM EDT SAT APR 29 2017

NJC019-021-023-025-027-035-290917-
/O.EXP.KPHI.SV.W.0026.000000T0000Z-170429T0915Z/
Morris NJ-Hunterdon NJ-Mercer NJ-Somerset NJ-Monmouth NJ-
Middlesex NJ-
507 AM EDT SAT APR 29 2017

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN MORRIS...
SOUTHEASTERN HUNTERDON...NORTHWESTERN MERCER...SOMERSET...
NORTHEASTERN MONMOUTH AND MIDDLESEX COUNTIES WILL EXPIRE AT 515 AM
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.

LAT...LON 4031 7485 4070 7476 4091 7431 4089 7434
      4086 7433 4079 7437 4075 7436 4067 7446
      4065 7441 4060 7446 4060 7421 4056 7421
      4055 7425 4050 7428 4046 7426 4044 7410
      4046 7401 4047 7401 4044 7398
TIME...MOT...LOC 0907Z 257DEG 49KT 4056 7422 

$$

SFJ

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 29, 2:54 AM EDTSpecial Weather StatementPHIBurlington36 min
Apr 29, 4:14 AM EDTSpecial Weather StatementPHIHunterdon, Middlesex, Somerset46 min
Apr 29, 4:20 AM EDTSevere Thunderstorm WarningPHIBurlington, Hunterdon, Mercer, Middlesex, Monmouth, Somerset40 min
Apr 29, 4:22 AM EDTSpecial Weather StatementPHIBurlington, Camden, Gloucester38 min
Apr 29, 4:29 AM EDTAreal Flood AdvisoryPHIHunterdon, Mercer, Middlesex, Morris, Somerset4 hr
Apr 29, 4:56 AM EDTSpecial Marine WarningPHI64 min
Apr 29, 4:56 AM EDTSpecial Weather StatementPHIBurlington, Mercer, Monmouth, Ocean49 min
Apr 29, 5:16 AM EDTSpecial Marine WarningPHI29 min
Apr 29, 6:16 AM EDTSpecial Marine WarningPHI29 min
Apr 29, 7:04 AM EDTAreal Flood WarningPHIHunterdon, Somerset4 hr
Apr 29, 3:12 AM EDTAreal Flood AdvisoryPHIBerks4 hr
Apr 29, 3:20 AM EDTSpecial Weather StatementPHIBerks, Lehigh, Northampton40 min
Apr 29, 3:51 AM EDTSpecial Weather StatementPHIBerks, Bucks, Chester, Delaware, Montgomery39 min

Nearby

Severe Thunderstorm Warnings in New Jersey, 2017Severe Thunderstorm Warnings in Pennsylvania, 2017Every 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.