Alert archive / New Jersey / Flash Flood Warnings in 2009

Flash Flood Warning 66, NWS Philadelphia/Mount Holly

October 24, 2009Hunterdon County, Morris County, Somerset County, New Jersey

NWS Philadelphia/Mount Holly issued this flash flood warning at Oct 24, 2009, 7:16 PM EDT for Hunterdon County, Morris County, Somerset County, New Jersey. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Oct 24, 2009, 7:16 PM EDT (23:16 UTC)
Expired
Oct 24, 2009, 10:15 PM EDT
In force
3 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
None

Counties Hunterdon County, NJ, Morris County, NJ, Somerset County, NJ

The radar

The Philadelphia radar (KDIX), 101 km from the middle of the area, began a volume at 23:16 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, 11.3 hours before the alert went out and 129 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 2009-10-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 74 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 2009-10-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 282 square meters per square second.1939587897Sfc1 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
74 J/kg
Mixed-layer CIN
-42 J/kg
Mixed-layer LCL
485 m above ground
0-6 km bulk shear
38 kt
0-1 km storm-relative helicity
282 m²/s²
0-3 km storm-relative helicity
325 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.6

Open this sounding in Storm Lab

The text

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

000 
WGUS51 KPHI 242316
FFWPHI
NJC019-027-035-250215-
/O.NEW.KPHI.FF.W.0066.091024T2316Z-091025T0215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
716 PM EDT SAT OCT 24 2009

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  MORRIS COUNTY IN NORTHERN NEW JERSEY...
  THIS INCLUDES THE CITY OF MORRISTOWN...
  NORTHWESTERN SOMERSET COUNTY IN NORTHERN NEW JERSEY...
  NORTHEASTERN HUNTERDON COUNTY IN NORTHWEST NEW JERSEY...

* UNTIL 1015 PM EDT

* AT 715 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  FLASH FLOODING FROM A THUNDERSTORM OVER THE WARNED AREA.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO ROCKAWAY...
  PARSIPPANY...MOUNTAIN LAKES...MORRIS PLAINS...MENDHAM...LINCOLN
  PARK...KINNELON...EAST HANOVER...DOVER...CHESTER AND BOONTON

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...HIGHWAYS AND UNDERPASSES. ADDITIONALLY...COUNTRY
ROADS AND FARMLANDS ALONG THE BANKS OF CREEKS...STREAMS AND OTHER LOW
LYING AREAS ARE SUBJECT TO FLOODING.

&&

LAT...LON 4090 7429 4089 7433 4087 7433 4086 7431
      4081 7433 4063 7468 4070 7488 4100 7436
      4091 7426 4089 7427

$$

RNS

The office that day

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

IssuedProductOfficeCountiesLasted
Oct 24, 4:49 PM EDTAreal Flood AdvisoryPHIHunterdon, Mercer, Somerset, Sussex, Warren4 hr
Oct 24, 6:19 PM EDTSevere Thunderstorm WarningPHISalem26 min
Oct 24, 6:28 PM EDTSevere Thunderstorm WarningPHIHunterdon, Somerset47 min
Oct 24, 6:31 PM EDTTornado WarningPHIHunterdon10 min
Oct 24, 7:24 PM EDTAreal Flood AdvisoryPHIBurlington, Camden, Gloucester, Middlesex, Monmouth, Ocean and 1 more3 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.