Alert archive / New Jersey / Flash Flood Warnings in 2019

Flash Flood Warning 60, NWS Philadelphia/Mount Holly

July 18, 20194 counties in New Jersey

NWS Philadelphia/Mount Holly issued this flash flood warning at Jul 18, 2019, 5:13 PM EDT for 4 counties in New Jersey. It was in force for 3 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: Jul 18, 2019, 5:13 PM EDT (21:13 UTC)
Expired: Jul 18, 2019, 8:35 PM EDT
In force: 3 hr
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Flood severity: None

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

The radar

The Philadelphia radar (KDIX), 48 km from the middle of the area, began a volume at 21:13 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
Jul 18, 5:20 PM EDT	FLASH FLOOD	2 Wsw Rossmoor, NJ	US-130 NORTHBOUND CLOSED AT DEY RD DUE TO FLOODING.
Jul 18, 5:45 PM EDT	FLASH FLOOD	1 Ssw Heathcote, NJ	US-1 SOUTH AT RAYMOND RD DOWN TO ONE LANE AND EXPECTED TO BE CLOSED ENTIRELY IF WATERS CONTINUE RISING. EXIT RAMP TO RAYMOND RD IS ALREADY CLOSED AND IMPASSABLE.
Jul 18, 5:45 PM EDT	FLASH FLOOD	Manalapan Twp, NJ	MULTIPLE WATER RESCUES AND STRANDED VEHICLES IN THE MANALAPAN AREA.

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, 9.2 hours before the alert went out and 136 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: 414 J/kg
Mixed-layer CIN: -31 J/kg
Mixed-layer LCL: 465 m above ground
0-6 km bulk shear: 13 kt
0-1 km storm-relative helicity: 81 m²/s²
0-3 km storm-relative helicity: 121 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

468 
WGUS51 KPHI 182113
FFWPHI
NJC021-023-025-035-190115-
/O.NEW.KPHI.FF.W.0060.190718T2113Z-190719T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
513 PM EDT Thu Jul 18 2019

The National Weather Service in Mount Holly NJ has issued a

* Flash Flood Warning for...
  Northeastern Mercer County in central New Jersey...
  South central Somerset County in northern New Jersey...
  Central Monmouth County in central New Jersey...
  Southern Middlesex County in northern New Jersey...

* Until 915 PM EDT.

* At 512 PM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Over two inches of rain has 
  already fallen in a short amount of time. Flash flooding is 
  expected to begin shortly in the areas of heaviest rain.

* Some locations that could experience flooding include...
  Old Bridge, East Brunswick, South Brunswick, Sayreville, Marlboro,
  Manalapan, Holmdel, Princeton, Matawan, Jamesburg, Hightstown,
  Cranbury, Rocky Hill, Princeton Meadows, Brownville, Kingston,
  Dayton, Plainsboro Center, Robertsville and North Brunswick
  Township.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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.

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 4024 7455 4041 7471 4048 7427 4044 7420
      4046 7418 4045 7416 4028 7413

$$

Robertson

1 follow-up statement

694 
WGUS71 KPHI 190035
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
835 PM EDT Thu Jul 18 2019

NJC021-023-025-035-190043-
/O.CAN.KPHI.FF.W.0060.000000T0000Z-190719T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Mercer NJ-Somerset NJ-Monmouth NJ-Middlesex NJ-
835 PM EDT Thu Jul 18 2019

...THE FLASH FLOOD WARNING FOR NORTHEASTERN MERCER...SOUTH CENTRAL
SOMERSET...CENTRAL MONMOUTH AND SOUTHERN MIDDLESEX COUNTIES IS
CANCELLED...

The heavy rain has ended. Flash flooding is no longer expected to 
pose a threat. Please continue to heed any remaining road closures 
as the water may be slow to recede in some areas.

LAT...LON 4024 7455 4041 7471 4048 7427 4044 7420
      4046 7418 4045 7416 4028 7413

$$

Robertson

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 17, 8:01 PM EDT	Areal Flood Advisory	PHI	Warren	88 min
Jul 17, 8:10 PM EDT	Special Marine Warning	PHI		95 min
Jul 17, 8:15 PM EDT	Severe Thunderstorm Warning	PHI	Atlantic, Burlington, Camden, Gloucester, Hunterdon, Mercer and 1 more	45 min
Jul 17, 8:39 PM EDT	Areal Flood Advisory	PHI	Morris, Sussex	3 hr
Jul 17, 8:40 PM EDT	Special Weather Statement	PHI	Atlantic, Burlington, Mercer, Middlesex, Monmouth, Ocean	65 min
Jul 17, 8:43 PM EDT	Special Marine Warning	PHI		92 min
Jul 17, 8:50 PM EDT	Severe Thunderstorm Warning	PHI	Middlesex, Monmouth, Somerset	40 min
Jul 17, 8:55 PM EDT	Areal Flood Advisory	PHI	Mercer, Middlesex, Somerset	49 min
Jul 17, 9:02 PM EDT	Flash Flood Warning	PHI	Mercer, Middlesex, Somerset	3 hr
Jul 17, 9:19 PM EDT	Severe Thunderstorm Warning	PHI	Middlesex, Monmouth, Ocean	41 min
Jul 17, 9:44 PM EDT	Special Marine Warning	PHI		61 min
Jul 17, 10:41 PM EDT	Special Marine Warning	PHI		49 min
Jul 17, 11:12 PM EDT	Areal Flood Warning	PHI	Somerset	3 hr
Jul 18, 1:30 PM EDT	Areal Flood Advisory	PHI	Gloucester	4 hr
Jul 18, 2:13 PM EDT	Areal Flood Advisory	PHI	Burlington, Camden, Gloucester, Ocean	4 hr
Jul 18, 2:24 PM EDT	Areal Flood Advisory	PHI	Salem	3 hr
Jul 18, 2:47 PM EDT	Flash Flood Warning	PHI	Burlington, Ocean	4 hr
Jul 18, 3:48 PM EDT	Areal Flood Advisory	PHI	Burlington, Mercer, Middlesex, Monmouth, Ocean	4 hr
Jul 18, 3:59 PM EDT	Areal Flood Advisory	PHI	Atlantic, Burlington, Camden, Gloucester, Ocean, Salem	3 hr
Jul 18, 4:19 PM EDT	Flash Flood Warning	PHI	Atlantic, Burlington, Ocean	3 hr
Jul 18, 4:30 PM EDT	Areal Flood Advisory	PHI	Hunterdon	4 hr
Jul 18, 4:52 PM EDT	Special Marine Warning	PHI		53 min
Jul 18, 4:53 PM EDT	Areal Flood Advisory	PHI	Mercer, Middlesex, Monmouth, Somerset	4 hr
Jul 18, 4:56 PM EDT	Areal Flood Advisory	PHI	Cumberland, Gloucester, Salem	3 hr
Jul 18, 5:57 PM EDT	Areal Flood Advisory	PHI	Cumberland, Salem	2 hr
Jul 18, 6:01 PM EDT	Flash Flood Warning	PHI	Hunterdon, Middlesex, Somerset	4 hr

Nearby

Flash Flood Warnings in New Jersey, 2019 Every flash flood warning in 2019

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.