Alert archive / New Jersey / Flash Flood Warnings in 2020

Flash Flood Warning 22, NWS Philadelphia/Mount Holly

July 10, 2020Middlesex County, Monmouth County, Somerset County, New Jersey

NWS Philadelphia/Mount Holly issued this flash flood warning at Jul 10, 2020, 1:15 PM EDT for Middlesex County, Monmouth County, Somerset County, New Jersey. It was in force for 4 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 10, 2020, 1:15 PM EDT (17:15 UTC)
Expired: Jul 10, 2020, 5:15 PM EDT
In force: 4 hr
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Flood severity: None

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

The radar

The Philadelphia radar (KDIX), 62 km from the middle of the area, began a volume at 17:18 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 10, 1:26 PM EDT	HEAVY RAIN 1.31	1 Sse Atlantic Highland, NJ	1.31 IN OF RAIN IN NAVESINK, NJ.
Jul 10, 1:53 PM EDT	FLOOD	1 Sse Highland Park, NJ	FLOODING ON U.S. HIGHWAY 1 NORTHBOUND RAMP TO STATE HIGHWAY 18 IN NEW BRUNSWICK. RAMP CLOSED.
Jul 10, 2:06 PM EDT	HEAVY RAIN 1.36	Woodbridge, NJ
Jul 10, 2:45 PM EDT	FLASH FLOOD	1 Sw North Brunswick, NJ	FLASH FLOODING ON STATE HIGHWAY 91 NEAR HURON ROAD. ROAD CLOSED. TIME ESTIMATED FROM RADAR AND SURROUNDING REPORTS.
Jul 10, 3:40 PM EDT	HEAVY RAIN 2.24	3 Nw Bridgewater, NJ
Jul 10, 3:40 PM EDT	HEAVY RAIN 2.24	Bridgewater, NJ	NJ-SM-5.

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, 5.3 hours before the alert went out and 132 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: 531 J/kg
Mixed-layer CIN: -3 J/kg
Mixed-layer LCL: 508 m above ground
0-6 km bulk shear: 14 kt
0-1 km storm-relative helicity: 50 m²/s²
0-3 km storm-relative helicity: 88 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

783 
WGUS51 KPHI 101715
FFWPHI
NJC023-025-035-102115-
/O.NEW.KPHI.FF.W.0022.200710T1715Z-200710T2115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
115 PM EDT Fri Jul 10 2020

The National Weather Service in Mount Holly NJ has issued a

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

* Until 515 PM EDT.

* At 113 PM EDT, Doppler radar indicated heavy rain falling across
  the warned area. Up to two inches of rain have already fallen.
  With additional rain to come, flash flooding is likely.

  HAZARD...Flash flooding caused by heavy rain.

  SOURCE...Radar indicated.

  IMPACT...Flooding of small creeks and streams, urban areas, 
           highways, streets and underpasses as well as other 
           drainage and low lying areas.

* Some locations that could experience flooding include...
  New Brunswick, Perth Amboy, Long Branch, Somerville, Sandy Hook,
  Somerset, Edison, Middletown, Old Bridge, East Brunswick,
  Bridgewater, South Brunswick, Sayreville, North Brunswick,
  Carteret, Tinton Falls, Holmdel, Middlesex, Red Bank and Bound
  Brook.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Protecting yourself from immediate threats to life and safety shall
take priority.  Whenever possible, as long as it does not cause
greater harm, all COVID-19 protective action guidance should be
followed.

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

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 4027 7397 4040 7474 4051 7479 4051 7478
      4058 7471 4062 7471 4064 7473 4069 7471
      4063 7442 4060 7446 4060 7421 4056 7421
      4050 7428 4047 7427 4044 7420 4041 7399
      4048 7402 4047 7400 4043 7397

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...1-3 INCHES IN 1 HOUR

$$

Kruzdlo

2 follow-up statements

911 
WGUS71 KPHI 101847
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
247 PM EDT Fri Jul 10 2020

NJC023-025-035-102115-
/O.CON.KPHI.FF.W.0022.000000T0000Z-200710T2115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Somerset NJ-Monmouth NJ-Middlesex NJ-
247 PM EDT Fri Jul 10 2020

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 515 PM EDT FOR
SOMERSET...NORTHEASTERN MONMOUTH AND MIDDLESEX COUNTIES...

At 246 PM EDT, Doppler radar and automated gauges indicated heavy 
rain across the warned area. Up to three inches of rain have already 
fallen. Flash flooding is ongoing or expected to begin shortly.

HAZARD...Flash flooding caused by heavy rain.

SOURCE...Radar and automated gauges.

IMPACT...Flooding of small creeks and streams, urban areas, 
         highways, streets and underpasses as well as other drainage 
         and low lying areas.

Some locations that could experience flooding include...
New Brunswick, Perth Amboy, Long Branch, Somerville, Sandy Hook,
Somerset, Edison, Middletown, Old Bridge, East Brunswick,
Bridgewater, South Brunswick, Sayreville, North Brunswick, Carteret,
Tinton Falls, Holmdel, Middlesex, Red Bank and Bound Brook.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Protecting yourself from immediate threats to life and safety shall
take priority.  Whenever possible, as long as it does not cause
greater harm, all COVID-19 protective action guidance should be
followed.

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

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 4027 7397 4040 7474 4051 7479 4051 7478
      4058 7471 4062 7471 4064 7473 4069 7471
      4063 7442 4060 7446 4060 7421 4056 7421
      4050 7428 4047 7427 4044 7420 4041 7399
      4048 7402 4047 7400 4043 7397

FLASH FLOOD...RADAR AND GAUGE INDICATED
EXPECTED RAINFALL...1-2 INCHES IN 1 HOUR

$$

Staarmann

882 
WGUS71 KPHI 102108
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
508 PM EDT Fri Jul 10 2020

NJC023-025-035-102116-
/O.EXP.KPHI.FF.W.0022.000000T0000Z-200710T2115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Somerset NJ-Monmouth NJ-Middlesex NJ-
508 PM EDT Fri Jul 10 2020

...THE FLASH FLOOD WARNING FOR SOMERSET...NORTHEASTERN MONMOUTH AND
MIDDLESEX COUNTIES WILL EXPIRE AT 515 PM EDT...

While heavy rain has ended, light to moderate rain will continue 
over the next few hours. However, the threat of flooding has 
diminished, so the Flash Flood Warning will be allowed to expire.
Please continue to heed any remaining road closures.

LAT...LON 4027 7397 4040 7474 4051 7479 4051 7478
      4058 7471 4062 7471 4064 7473 4069 7471
      4063 7442 4060 7446 4060 7421 4056 7421
      4050 7428 4047 7427 4044 7420 4041 7399
      4048 7402 4047 7400 4043 7397

$$

Miketta

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 10, 6:48 AM EDT	Special Marine Warning	PHI		57 min
Jul 10, 7:11 AM EDT	Special Marine Warning	PHI		94 min
Jul 10, 7:42 AM EDT	Special Marine Warning	PHI		33 min
Jul 10, 8:20 AM EDT	Flash Flood Warning Considerable damage threat	PHI	Cape May	4 hr
Jul 10, 8:34 AM EDT	Special Marine Warning	PHI		30 min
Jul 10, 9:01 AM EDT	Flash Flood Warning	PHI	Atlantic, Cape May	3 hr
Jul 10, 9:13 AM EDT	Special Marine Warning	PHI		21 min
Jul 10, 9:27 AM EDT	Areal Flood Advisory	PHI	Atlantic, Burlington, Camden, Cape May, Cumberland, Gloucester and 1 more	4 hr
Jul 10, 10:31 AM EDT	Flash Flood Warning	PHI	Atlantic, Burlington, Ocean	4 hr
Jul 10, 10:35 AM EDT	Areal Flood Advisory	PHI	Atlantic, Burlington, Camden, Gloucester, Ocean	4 hr
Jul 10, 11:02 AM EDT	Areal Flood Advisory	PHI	Camden, Gloucester, Salem	4 hr
Jul 10, 11:08 AM EDT	Areal Flood Advisory	PHI	Burlington, Camden, Gloucester, Mercer, Monmouth, Ocean	4 hr
Jul 10, 12:35 PM EDT	Areal Flood Advisory	PHI	Mercer, Middlesex, Monmouth, Ocean, Somerset	3 hr
Jul 10, 12:49 PM EDT	Flash Flood Warning	PHI	Mercer, Middlesex, Monmouth, Ocean, Somerset	4 hr
Jul 10, 12:56 PM EDT	Flash Flood Warning	PHI	Burlington, Camden, Cumberland, Gloucester, Salem	4 hr
Jul 10, 1:41 PM EDT	Areal Flood Advisory	PHI	Hunterdon, Mercer, Somerset	4 hr
Jul 10, 2:08 PM EDT	Areal Flood Advisory	PHI	Morris, Somerset	4 hr
Jul 10, 3:12 PM EDT	Areal Flood Advisory	PHI	Sussex, Warren	4 hr
Jul 10, 4:30 PM EDT	Areal Flood Advisory	PHI	Hunterdon, Mercer, Middlesex, Monmouth, Ocean	4 hr
Jul 10, 4:48 PM EDT	Areal Flood Warning	PHI	Burlington, Camden, Cumberland, Gloucester, Salem	4 hr
Jul 10, 5:39 PM EDT	Areal Flood Advisory	PHI	Hunterdon, Mercer, Somerset	4 hr

Nearby

Flash Flood Warnings in New Jersey, 2020 Every flash flood warning in 2020

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.