Alert archive / New Jersey / Flash Flood Warnings in 2016

Flash Flood Warning 25, NWS Philadelphia/Mount Holly

July 30, 2016Mercer County, Middlesex County, Somerset County, New Jersey

NWS Philadelphia/Mount Holly issued this flash flood warning at Jul 30, 2016, 3:58 PM EDT for Mercer County, Middlesex County, Somerset County, New Jersey. It was in force for 7 hr. 6 reports 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
Jul 30, 2016, 3:58 PM EDT (19:58 UTC)
Expired
Jul 30, 2016, 10:30 PM EDT
In force
7 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
None

Counties Mercer County, NJ, Middlesex County, NJ, Somerset County, NJ

The radar

The Philadelphia radar (KDIX), 48 km from the middle of the area, began a volume at 19:59 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

TimeReportWhereRemark
Jul 30, 4:04 PM EDTFLASH FLOODWest Windsor Twp, NJMULTIPLE ROADS REPORTED TO BE FLOODED AND IMPASSABLE. FLOODING REPORTED ON US 1... COUNTY ROUTE 571... WASHINGTON ROAD AND ALEXANDER ROAD. WATER RESCUES REPORTED TO BE ONGOING IN THE PRINCETON AREA.
Jul 30, 4:20 PM EDTFLASH FLOODPlainsboro, NJFLASH FLOODING OCCURING IN PLAINSBORO. WATER REPORTED UP TO THE BUMPERS OF CARS.
Jul 30, 4:20 PM EDTFLASH FLOODPlainsboro, NJFLASH FLOODING OCCURRING IN PLAINSBORO. WATER REPORTED UP TO THE BUMPERS OF CARS.
Jul 30, 4:30 PM EDTFLASH FLOODPrinceton Junction, NJTHE PRINCETON JUNCTION TRAIN STATION INUNDATED BY FLOOD WATERS. THE WATER IS UP TO THE TOP OF THE TUNNEL.
Jul 30, 5:30 PM EDTHEAVY RAIN 5.75Plainsboro, NJ
Jul 30, 6:25 PM EDTFLASH FLOODWest Windsor Twp, NJWEST WINDSOR TOWNSHIP DECLARED A STATE OF EMERGENCY DUE TO WIDESPREAD FLASH FLOODING. THIS INCLUDED DOZENS OF DISABLED VEHICLES REQUIRING WATER RESCUES.

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, 8.0 hours before the alert went out and 159 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 2016-07-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 176 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 2016-07-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -7 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
176 J/kg
Mixed-layer CIN
-67 J/kg
Mixed-layer LCL
858 m above ground
0-6 km bulk shear
29 kt
0-1 km storm-relative helicity
-7 m²/s²
0-3 km storm-relative helicity
7 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

168 
WGUS51 KPHI 301958
FFWPHI
NJC021-023-035-310000-
/O.NEW.KPHI.FF.W.0025.160730T1958Z-160731T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
358 PM EDT SAT JUL 30 2016

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ  HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  CENTRAL MERCER COUNTY IN CENTRAL NEW JERSEY...
  SOUTH CENTRAL SOMERSET COUNTY IN NORTHERN NEW JERSEY...
  WEST CENTRAL MIDDLESEX COUNTY IN NORTHERN NEW JERSEY...

* UNTIL 800 PM EDT
    
* AT 355 PM EDT...DOPPLER RADAR INDICATED A CLUSTER OF THUNDERSTORMS
  PRODUCING HEAVY RAIN ACROSS PORTIONS OF THE WARNED AREA. UP TO TWO
  INCHES OF RAIN HAVE ALREADY FALLEN. UP TO FOUR INCHES IS POSSIBLE.
  BECAUSE THIS AMOUNT OF RAIN WILL FALL IN A SHORT PERIOD OF TIME,
  FLASH FLOODING IS LIKELY. 

* SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
  SOUTH BRUNSWICK...EWING...PRINCETON...ROCKY HILL...KENDALL PARK...
  PLAINSBORO CENTER...LAWRENCEVILLE...EDINBURG...KINGSTON...
  PRINCETON MEADOWS...MERCERVILLE-HAMILTON SQUARE...
  MONMOUTH JUNCTION...HEATHCOTE...
  PRINCETON JUNCTION AND PRINCETON NORTH.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TURN AROUND...DON'T DROWN WHEN ENCOUNTERING FLOODED ROADS. MOST FLOOD
DEATHS OCCUR IN VEHICLES.

DRIVING INTO FLOOD WATERS COULD PUT YOUR LIFE AT RISK AND COST YOU
THOUSANDS OF DOLLARS IN VEHICLE REPAIRS. FLOOD WATERS MAY BE DEEPER
THAT YOU THINK.  TURN AROUND AND FIND AN ALTERNATE ROUTE.

&&

LAT...LON 4041 7452 4023 7463 4026 7476 4043 7465

$$

KRUZDLO
3 follow-up statements
871 
WGUS71 KPHI 302146
FFSPHI

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
546 PM EDT SAT JUL 30 2016

NJC021-023-035-310000-
/O.CON.KPHI.FF.W.0025.000000T0000Z-160731T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
MERCER NJ-SOMERSET NJ-MIDDLESEX NJ-
546 PM EDT SAT JUL 30 2016

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 800 PM EDT FOR
CENTRAL MERCER...SOUTH CENTRAL SOMERSET AND WEST CENTRAL MIDDLESEX
COUNTIES...

AT 539 PM EDT...IT WAS STILL RAINING ACROSS THE WARNED AREA, BUT THE
INTENSITY WAS SLOWLY DIMINISHING. CREEKS ARE RUNNING HIGH, ROADS
HAVE BEEN CLOSED, AND WATER RESCUES HAVE BEEN CONDUCTED. UP TO FIVE
INCHES OF RAIN HAVE FALLEN THE LAST FEW HOURS. THE WORST FLOODING
HAS BEEN ALONG THE ROUTE ONE CORRIDOR FROM PRINCETON TO PLAINSBORO.
THIS IS A DANGEROUS SITUATION. DO NOT GO AROUND ROAD BARRIERS. MOVE
TO HIGHER GROUND IF NEEDED.

SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
SOUTH BRUNSWICK...EWING...PRINCETON...ROCKY HILL...KENDALL PARK...
PLAINSBORO CENTER...LAWRENCEVILLE...EDINBURG...KINGSTON...
PRINCETON MEADOWS...MERCERVILLE-HAMILTON SQUARE...
MONMOUTH JUNCTION...HEATHCOTE...
PRINCETON JUNCTION AND PRINCETON NORTH.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

DRIVING INTO FLOOD WATERS COULD PUT YOUR LIFE AT RISK AND COST YOU
THOUSANDS OF DOLLARS IN VEHICLE REPAIRS. FLOOD WATERS MAY BE DEEPER
THAT YOU THINK.  TURN AROUND AND FIND AN ALTERNATE ROUTE.

TURN AROUND...DON'T DROWN WHEN ENCOUNTERING FLOODED ROADS. MOST FLOOD
DEATHS OCCUR IN VEHICLES.

&&

LAT...LON 4041 7452 4023 7463 4026 7476 4043 7465

$$

KRUZDLO
239 
WGUS51 KPHI 302358
FFWPHI
NJC021-023-035-310230-
/O.EXT.KPHI.FF.W.0025.000000T0000Z-160731T0230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
758 PM EDT SAT JUL 30 2016

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ  HAS EXTENDED THE

* FLASH FLOOD WARNING FOR...
  CENTRAL MERCER COUNTY IN CENTRAL NEW JERSEY...
  SOUTH CENTRAL SOMERSET COUNTY IN NORTHERN NEW JERSEY...
  WEST CENTRAL MIDDLESEX COUNTY IN NORTHERN NEW JERSEY...

* UNTIL 1030 PM EDT
    
* AT 750 PM EDT...RAIN WAS STILL FALLING ACROSS THE WARNED AREA
  ALTHOUGH RAIN RATES HAVE IMPROVED AND ARE NOW LESS THAN AN INCH
  PER HOUR. CREEKS CONTINUE TO RUN HIGH, ROADS HAVE BEEN CLOSED, AND
  WATER RESCUES HAVE BEEN CONDUCTED. UP TO SIX INCHES OF RAIN HAVE
  FALLEN SINCE 300 PM. THE WORST FLOODING REPORTED HAS BEEN ALONG
  THE ROUTE ONE CORRIDOR FROM PRINCETON TO PLAINSBORO. UNTIL THE
  WATER HAS SUBSIDED, THIS REMAINS A DANGEROUS SITUATION. DO NOT GO
  AROUND ROAD BARRIERS. MOVE TO HIGHER GROUND. THE WEST WINDSOR
  POLICE DEPARTMENT HAS DECLARED A STATE OF EMERGENCY FOR WEST
  WINDSOR TOWNSHIP. 

* SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
  SOUTH BRUNSWICK...EWING...PRINCETON...ROCKY HILL...KENDALL PARK...
  PLAINSBORO CENTER...LAWRENCEVILLE...EDINBURG...KINGSTON...
  PRINCETON MEADOWS...MERCERVILLE-HAMILTON SQUARE...
  MONMOUTH JUNCTION...HEATHCOTE...
  PRINCETON JUNCTION AND PRINCETON NORTH.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

STAY AWAY OR BE SWEPT AWAY. RIVER BANKS AND CULVERTS CAN BECOME
UNSTABLE AND UNSAFE.

TURN AROUND...DON'T DROWN WHEN ENCOUNTERING FLOODED ROADS. MOST FLOOD
DEATHS OCCUR IN VEHICLES.

&&

LAT...LON 4041 7452 4023 7463 4026 7476 4043 7465

$$

KRUZDLO
298 
WGUS71 KPHI 310225
FFSPHI

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1025 PM EDT SAT JUL 30 2016

NJC021-023-035-310233-
/O.EXP.KPHI.FF.W.0025.000000T0000Z-160731T0230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
MERCER NJ-SOMERSET NJ-MIDDLESEX NJ-
1025 PM EDT SAT JUL 30 2016

...THE FLASH FLOOD WARNING FOR CENTRAL MERCER...SOUTH CENTRAL
SOMERSET AND WEST CENTRAL MIDDLESEX COUNTIES WILL EXPIRE AT 1030 PM
EDT...

WATER IS NO LONGER RISING RAPIDLY. THE FLASH FLOOD WARNING HAS
BEEN REPLACED BY A FLOOD WARNING WHICH IS IN EFFECT UNTIL 215 AM. 

LAT...LON 4041 7452 4023 7463 4026 7476 4043 7465

$$

KRUZDLO

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 30, 1:55 PM EDTSpecial Weather StatementPHIHunterdon50 min
Jul 30, 2:34 PM EDTAreal Flood AdvisoryPHIMiddlesex, Monmouth4 hr
Jul 30, 2:40 PM EDTSpecial Weather StatementPHIMorris35 min
Jul 30, 2:59 PM EDTAreal Flood AdvisoryPHIHunterdon, Warren4 hr
Jul 30, 3:03 PM EDTSevere Thunderstorm WarningPHIMorris47 min
Jul 30, 3:06 PM EDTAreal Flood AdvisoryPHIMercer, Middlesex, Somerset4 hr
Jul 30, 3:34 PM EDTAreal Flood AdvisoryPHIMercer, Middlesex4 hr
Jul 30, 3:45 PM EDTAreal Flood AdvisoryPHIMorris, Sussex4 hr
Jul 30, 3:49 PM EDTSpecial Weather StatementPHIMercer, Middlesex26 min
Jul 30, 4:37 PM EDTFlash Flood WarningPHIMiddlesex6 hr
Jul 30, 6:26 PM EDTFlash Flood Warning EmergencyPHIMercer4 hr

Nearby

Flash Flood Warnings in New Jersey, 2016Every flash flood warning in 2016

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.