Alert archive / New Jersey / Flash Flood Warnings in 2019

Flash Flood Warning 55, NWS Philadelphia/Mount Holly

July 17, 2019Mercer County, Middlesex County, Somerset County, New Jersey

NWS Philadelphia/Mount Holly issued this flash flood warning at Jul 17, 2019, 9:02 PM EDT for Mercer County, Middlesex County, Somerset County, New Jersey. It was in force for 3 hr. 1 report 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 17, 2019, 9:02 PM EDT (01:02 UTC)
Expired: Jul 18, 2019, 12:00 AM 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, Somerset County, NJ

The radar

The Philadelphia radar (KDIX), 52 km from the middle of the area, began a volume at 01:06 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 17, 9:40 PM EDT	FLASH FLOOD	1 Ssw Hopelawn, NJ	FLOODING OCCURRED ON US ROUTE 9 AT SMITH STREET IN WOODBRIDGE TOWNSHIP, RESULTING IN RAMP CLOSURES.

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, 1.0 hours before the alert went out and 150 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: 1392 J/kg
Mixed-layer CIN: -88 J/kg
Mixed-layer LCL: 975 m above ground
0-6 km bulk shear: 34 kt
0-1 km storm-relative helicity: 106 m²/s²
0-3 km storm-relative helicity: 133 m²/s²
Significant tornado parameter: 0.4
Supercell composite: 4.0

Open this sounding in Storm Lab

The text

As transmitted.

062 
WGUS51 KPHI 180102
FFWPHI
NJC021-023-035-180400-
/O.NEW.KPHI.FF.W.0055.190718T0102Z-190718T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
902 PM EDT Wed Jul 17 2019

The National Weather Service in Mount Holly NJ has issued a

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

* Until midnight EDT.

* At 901 PM EDT, Doppler radar indicated thunderstorms producing 
  very heavy rain across the warned area. Rainfall rates up to 2 
  inches per hour have been reported. Flash flooding is expected in 
  the areas of heaviest rain.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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 4055 7425 4050 7426 4050 7428 4045 7423
      4040 7425 4027 7441 4018 7461 4014 7459
      4017 7467 4034 7489 4035 7485 4038 7486
      4038 7481 4042 7480 4043 7475 4045 7476
      4050 7459 4060 7446 4059 7420

$$

JJM

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, 9:19 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, 5:13 PM EDT	Flash Flood Warning	PHI	Mercer, Middlesex, Monmouth, Somerset	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.