Alert archive / New Jersey / Flash Flood Warnings in 2018

Flash Flood Warning 51, NWS Philadelphia/Mount Holly

August 4, 2018Morris County, New Jersey

NWS Philadelphia/Mount Holly issued this flash flood warning at Aug 4, 2018, 6:19 AM EDT for Morris County, New Jersey. It was in force for 4 hr. 3 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: Aug 4, 2018, 6:19 AM EDT (10:19 UTC)
Expired: Aug 4, 2018, 10:15 AM EDT
In force: 4 hr
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Flood severity: None

County Morris County, NJ

The radar

The Philadelphia radar (KDIX), 106 km from the middle of the area, began a volume at 10:20 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

Time	Report	Where	Remark
Aug 4, 7:45 AM EDT	FLASH FLOOD	1 Ene Parsippany-Troy H, NJ	WATER RESCUE REPORTED ON U.S. HIGHWAY 46 NEAR NORTH BEVERWYCK ROAD. ADDITIONALLY...WESTBOUND U.S. HIGHWAY 46 EXIT TO WATERVIEW BOULEVARD WAS CLOSED FROM A CONSTRUCTION SITE DEBRIS FLOW. EDWARDS ROAD WAS CLOSED BETWEEN U.S. HIGHWAY 46 AND NEW ROAD.
Aug 4, 8:00 AM EDT	FLASH FLOOD	1 Ene Parsippany-Troy H, NJ	WATER RESCUE REPORTED ON U.S. HIGHWAY 46 NEAR NORTH BEVERWYCK ROAD. ADDITIONALLY...WESTBOUND U.S. HIGHWAY 46 EXIT TO WATERVIEW BOULEVARD WAS CLOSED FROM A CONSTRUCTION SITE DEBRIS FLOW. EDWARDS ROAD WAS CLOSED BETWEEN U.S. HIGHWAY 46 AND NEW ROAD. TIME APPROXI
Aug 4, 8:40 AM EDT	FLOOD	1 Nw Parsippany-Troy Hi, NJ	FLOODING ON US 46 IN BOTH DIRECTIONS EAST OF I-287. ALL LANES CLOSED AND DETOURED.

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 00:00Z, 10.3 hours before the alert went out and 137 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1302 J/kg
Mixed-layer CIN: -2 J/kg
Mixed-layer LCL: 561 m above ground
0-6 km bulk shear: 20 kt
0-1 km storm-relative helicity: 12 m²/s²
0-3 km storm-relative helicity: 32 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.3

Open this sounding in Storm Lab

The text

As transmitted.

912 
WGUS51 KPHI 041019
FFWPHI
NJC027-041415-
/O.NEW.KPHI.FF.W.0051.180804T1019Z-180804T1415Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
619 AM EDT SAT AUG 4 2018

The National Weather Service in Mount Holly NJ has issued a

* Flash Flood Warning for...
  Morris County in northern New Jersey...

* Until 1015 AM EDT.

* At 619 AM EDT, Doppler radar and automated rain gauges indicated 
  heavy rain falling across the warned area. River gauges are rising 
  rapidly and are expected to reach flood stage soon. Flash flooding 
  is expected to begin shortly in the areas of heaviest rain.

* Some locations that could experience flooding include...
  Morristown, Dover, Madison, Hopatcong, Florham Park, East Hanover,
  Lincoln Park, Kinnelon, Hackettstown, Chatham, Boonton, Butler,
  Wharton, Rockaway, Morris Plains, Mount Arlington, Mendham,
  Mountain Lakes, Stanhope and Riverdale.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around...don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

Please report flooding to your local law enforcement agency when you
can do so safely.

A Flash Flood Warning means that flooding is imminent or occurring.
If you are in the warned area move to higher ground immediately.
Residents living along streams and creeks should take immediate
precautions to protect life and property.

&&

LAT...LON 4091 7433 4086 7432 4079 7437 4074 7437
      4065 7451 4076 7456 4072 7474 4079 7489
      4091 7476 4090 7471 4092 7465 4097 7464
      4108 7450 4104 7450 4105 7445 4102 7443
      4103 7442 4100 7430 4097 7428 4090 7427

$$

CMS

2 follow-up statements

402 
WGUS71 KPHI 041237
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
837 AM EDT SAT AUG 4 2018

NJC027-041415-
/O.CON.KPHI.FF.W.0051.000000T0000Z-180804T1415Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Morris NJ-
837 AM EDT SAT AUG 4 2018

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1015 AM EDT FOR
MORRIS COUNTY...

At 834 AM EDT, local law enforcement reported flooding across the 
warned area this morning. Up to four inches of rain has already 
fallen with with additional rainfall occurring in some areas. Areas 
of flooding will continue through the morning hours.

Some locations that could experience flooding include...
Morristown, Dover, Madison, Hopatcong, Florham Park, East Hanover,
Lincoln Park, Kinnelon, Hackettstown, Chatham, Boonton, Butler,
Wharton, Rockaway, Morris Plains, Mount Arlington, Mendham, Mountain
Lakes, Stanhope and Riverdale.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around...don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

Excessive runoff from heavy rainfall will cause flooding of small
creeks and streams, urban areas, highways, streets and underpasses as
well as other drainage areas and low lying spots.

Please report flooding to your local law enforcement agency when you
can do so safely.

&&

LAT...LON 4091 7433 4086 7432 4079 7437 4074 7437
      4065 7451 4076 7456 4072 7474 4079 7489
      4091 7476 4090 7471 4092 7465 4097 7464
      4108 7450 4104 7450 4105 7445 4102 7443
      4103 7442 4100 7430 4097 7428 4090 7427

$$

Robertson

046 
WGUS71 KPHI 041409
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
1009 AM EDT SAT AUG 4 2018

NJC027-041416-
/O.EXP.KPHI.FF.W.0051.000000T0000Z-180804T1415Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Morris NJ-
1009 AM EDT SAT AUG 4 2018

...THE FLASH FLOOD WARNING FOR MORRIS COUNTY WILL EXPIRE AT 1015 AM
EDT...

The heavy rain has ended. However, widespread rainfall amounts of 
two to four inches of rain fell across the area which will continue 
to lead to residual flooding another couple of hours. The Flash 
Flood Warning will be allowed to expire and an Area Flood Warning 
will be issued to replace it. Please continue to heed any remaining 
road closures.

LAT...LON 4091 7433 4086 7432 4079 7437 4074 7437
      4065 7451 4076 7456 4072 7474 4079 7489
      4091 7476 4090 7471 4092 7465 4097 7464
      4108 7450 4104 7450 4105 7445 4102 7443
      4103 7442 4100 7430 4097 7428 4090 7427

$$

Robertson

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 3, 9:10 PM EDT	Areal Flood Advisory	PHI	Sussex, Warren	4 hr
Aug 3, 10:07 PM EDT	Special Weather Statement	PHI	Warren	53 min
Aug 3, 10:35 PM EDT	Special Weather Statement	PHI	Morris, Sussex, Warren	55 min
Aug 4, 2:53 AM EDT	Areal Flood Advisory	PHI	Warren	4 hr
Aug 4, 3:09 AM EDT	Special Weather Statement	PHI	Warren	51 min
Aug 4, 3:14 AM EDT	Areal Flood Advisory	PHI	Sussex	4 hr
Aug 4, 3:55 AM EDT	Special Weather Statement	PHI	Sussex	65 min
Aug 4, 3:58 AM EDT	Areal Flood Warning	PHI	Sussex, Warren	33 hr
Aug 4, 5:12 AM EDT	Areal Flood Advisory	PHI	Morris	3 hr
Aug 4, 5:45 AM EDT	Areal Flood Advisory	PHI	Hunterdon	7 hr
Aug 4, 5:56 AM EDT	Areal Flood Advisory	PHI	Morris	3 hr
Aug 4, 6:55 AM EDT	Areal Flood Advisory	PHI	Hunterdon, Mercer, Somerset	4 hr
Aug 4, 8:19 AM EDT	Areal Flood Advisory	PHI	Middlesex, Somerset	4 hr
Aug 4, 9:32 AM EDT	Flash Flood Warning	PHI	Somerset	3 hr
Aug 4, 9:39 AM EDT	Small Craft Advisory	PHI		6 hr
Aug 4, 10:16 AM EDT	Areal Flood Warning	PHI	Morris	4 hr
Aug 4, 10:51 AM EDT	Areal Flood Warning	PHI	Hunterdon, Somerset	4 hr
Aug 4, 12:13 PM EDT	Areal Flood Warning	PHI	Middlesex, Somerset	2 hr
Aug 4, 4:41 PM EDT	Severe Thunderstorm Warning	PHI	Warren	34 min
Aug 4, 5:04 PM EDT	Special Weather Statement	PHI	Hunterdon	56 min

Nearby

Flash Flood Warnings in New Jersey, 2018 Every flash flood 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.