Alert archive / New Jersey / Flash Flood Warnings in 2009

Flash Flood Warning 25, NWS Philadelphia/Mount Holly

July 31, 20096 counties in New Jersey

NWS Philadelphia/Mount Holly issued this flash flood warning at Jul 31, 2009, 4:56 PM EDT for 6 counties in New Jersey. It was in force for 114 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 31, 2009, 4:56 PM EDT (20:56 UTC)
Expired
Jul 31, 2009, 6:50 PM EDT
In force
114 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
None

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

The radar

The Philadelphia radar (KDIX), 61 km from the middle of the area, began a volume at 20:58 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, 8.9 hours before the alert went out and 144 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 2009-07-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 48 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 2009-07-31The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 133 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
48 J/kg
Mixed-layer CIN
-90 J/kg
Mixed-layer LCL
1022 m above ground
0-6 km bulk shear
40 kt
0-1 km storm-relative helicity
133 m²/s²
0-3 km storm-relative helicity
184 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.8

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
WGUS51 KPHI 312056
FFWPHI
NJC019-021-023-025-027-035-010100-
/O.NEW.KPHI.FF.W.0025.090731T2056Z-090801T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
456 PM EDT FRI JUL 31 2009

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  MERCER COUNTY IN CENTRAL NEW JERSEY...
  THIS INCLUDES THE CITY OF TRENTON...
  WESTERN MONMOUTH COUNTY IN CENTRAL NEW JERSEY...
  MIDDLESEX COUNTY IN NORTHERN NEW JERSEY...
  THIS INCLUDES THE CITIES OF...PERTH AMBOY...NEW BRUNSWICK...
  SOUTHEASTERN MORRIS COUNTY IN NORTHERN NEW JERSEY...
  THIS INCLUDES THE CITY OF MORRISTOWN...
  SOMERSET COUNTY IN NORTHERN NEW JERSEY...
  THIS INCLUDES THE CITY OF SOMERVILLE...
  HUNTERDON COUNTY IN NORTHWEST NEW JERSEY...

* UNTIL 900 PM EDT

* AT 453 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  AN AREA OF EXCESSIVE RAINFALL OVER THE WARNED AREA.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO MANVILLE...
  MILLINGTON...MARTINSVILLE...BRIDGEWATER...BASKING RIDGE...WHITE
  HOUSE STATION...PEAPACK AND GLADSTONE...PARSIPPANY...MIDDLESEX...
  MADISON...LEBANON...FAR HILLS...EAST HANOVER...COLONIA...CARTERET
  AND BOUND BROOK

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING.  
DO NOT ATTEMPT TO CROSS SWIFTLY FLOWING WATERS OR WATERS OF UNKNOWN 
DEPTH BY FOOT OR BY AUTOMOBILE.

&&

LAT...LON 4007 7456 4013 7460 4017 7468 4015 7472
      4025 7484 4040 7497 4042 7506 4054 7507
      4094 7428 4090 7427 4089 7433 4086 7431
      4074 7436 4067 7445 4066 7440 4059 7444
      4059 7420 4047 7427 4046 7412 4043 7408

$$

KRUZDLO
1 follow-up statement
000 
WGUS71 KPHI 312250
FFSPHI

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
650 PM EDT FRI JUL 31 2009

NJC019-021-023-025-027-035-312300-
/O.CAN.KPHI.FF.W.0025.000000T0000Z-090801T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
MORRIS NJ-HUNTERDON NJ-SOMERSET NJ-MERCER NJ-MIDDLESEX NJ-MONMOUTH 
NJ-
650 PM EDT FRI JUL 31 2009

...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR WESTERN MONMOUTH...
MIDDLESEX...MERCER...SOMERSET...HUNTERDON AND SOUTHEASTERN MORRIS 
COUNTIES...

LAT...LON 4007 7456 4013 7460 4017 7468 4015 7472
      4025 7484 4040 7497 4042 7506 4054 7507
      4094 7428 4090 7427 4089 7433 4086 7431
      4074 7436 4067 7445 4066 7440 4059 7444
      4059 7420 4047 7427 4046 7412 4043 7408

$$

KRUZDLO

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 31, 2:13 PM EDTFlash Flood WarningPHISussex4 hr
Jul 31, 2:36 PM EDTFlash Flood WarningPHIHunterdon, Morris, Sussex, Warren4 hr
Jul 31, 4:03 PM EDTSevere Thunderstorm WarningPHIGloucester, Salem57 min
Jul 31, 4:08 PM EDTFlash Flood WarningPHIBurlington, Camden, Gloucester, Salem3 hr
Jul 31, 4:23 PM EDTSpecial Marine WarningPHI67 min
Jul 31, 4:31 PM EDTSevere Thunderstorm WarningPHIAtlantic, Burlington, Camden, Gloucester, Salem59 min
Jul 31, 4:39 PM EDTSevere Thunderstorm WarningPHIAtlantic, Burlington, Camden, Cape May, Cumberland, Gloucester and 2 more96 min
Jul 31, 5:07 PM EDTFlash Flood WarningPHIAtlantic, Burlington, Camden, Cumberland, Gloucester, Salem3 hr
Jul 31, 5:10 PM EDTTornado WarningPHIBurlington, Ocean21 min
Jul 31, 5:14 PM EDTSpecial Marine WarningPHI2 hr
Jul 31, 5:15 PM EDTSevere Thunderstorm WarningPHIAtlantic, Ocean60 min
Jul 31, 5:16 PM EDTSpecial Marine WarningPHI119 min
Jul 31, 5:31 PM EDTFlash Flood WarningPHIBurlington, Monmouth, Ocean4 hr
Jul 31, 5:48 PM EDTAreal Flood AdvisoryPHIAtlantic, Burlington, Cape May, Cumberland, Ocean3 hr

Nearby

Flash Flood Warnings in New Jersey, 2009Every flash flood warning in 2009

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.