Alert archive / New Jersey / Flash Flood Warnings in 2019

Flash Flood Warning 54, NWS Philadelphia/Mount Holly

July 17, 2019Hunterdon County, Morris County, Somerset County, New Jersey

NWS Philadelphia/Mount Holly issued this flash flood warning at Jul 17, 2019, 7:44 PM EDT for Hunterdon County, Morris County, Somerset County, New Jersey. It was in force for 3 hr. 5 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 17, 2019, 7:44 PM EDT (23:44 UTC)
Expired: Jul 17, 2019, 10:45 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), 90 km from the middle of the area, began a volume at 23:45 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, 8:00 PM EDT	FLASH FLOOD	2 E White House Station, NJ	US ROUTE 22 WAS CLOSED IN BOTH DIRECTIONS TO THE WEST OF RIDGE ROAD IN READINGTON TOWNSHIP.
Jul 17, 8:00 PM EDT	HEAVY RAIN 2.3	Lebanon, NJ	FELL IN 45 MINUTES.
Jul 17, 9:10 PM EDT	FLASH FLOOD	1 N Somerville, NJ	US ROUTE 202 SOUTHBOUND WAS CLOSED NEAR US ROUTE 22 IN BRIDGEWATER TOWNSHIP DUE TO FLASH FLOODING.
Jul 17, 9:15 PM EDT	FLASH FLOOD	2 Ssw Martinsville, NJ	FLOODING ON US ROUTE 22 AT INTERSTATE 287 IN BRIDGEWATER TOWNSHIP RESULTING IN RAMP CLOSURES.
Jul 17, 9:45 PM EDT	FLOOD	2 Ssw Martinsville, NJ	FLOODING ON US-22 EASTBOUND RAMP TO I-287 SOUTHBOUND. RAMP 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 12:00Z, 11.7 hours before the alert went out and 138 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: 1986 J/kg
Mixed-layer CIN: -43 J/kg
Mixed-layer LCL: 865 m above ground
0-6 km bulk shear: 22 kt
0-1 km storm-relative helicity: 157 m²/s²
0-3 km storm-relative helicity: 170 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 5.2

Open this sounding in Storm Lab

The text

As transmitted.

178 
WGUS51 KPHI 172344
FFWPHI
NJC019-027-035-180245-
/O.NEW.KPHI.FF.W.0054.190717T2344Z-190718T0245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

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

The National Weather Service in Mount Holly NJ has issued a

* Flash Flood Warning for...
  Morris County in northern New Jersey...
  Eastern Hunterdon County in northwestern New Jersey...
  Somerset County in northern New Jersey...

* Until 1045 PM EDT.

* At 742 PM EDT, Doppler radar indicated thunderstorms moving from 
  west to east across the warned area producing heavy rain at rates 
  of two or more inches per hours.  Flash flooding is expected in 
  locations that receive the heaviest rain.
  
  
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4091 7433 4086 7432 4076 7437 4075 7436
      4067 7446 4066 7445 4066 7440 4063 7442
      4057 7453 4052 7450 4043 7494 4069 7500
      4082 7483 4088 7480 4098 7428 4092 7429
      4090 7427

$$

jjm

1 follow-up statement

749 
WGUS71 KPHI 180239
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
1039 PM EDT Wed Jul 17 2019

NJC019-027-035-180248-
/O.EXP.KPHI.FF.W.0054.000000T0000Z-190718T0245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Morris NJ-Hunterdon NJ-Somerset NJ-
1039 PM EDT Wed Jul 17 2019

...THE FLASH FLOOD WARNING FOR MORRIS...EASTERN HUNTERDON AND
SOMERSET COUNTIES WILL EXPIRE AT 1045 PM EDT...

The heavy rain has ended. 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 4091 7433 4086 7432 4076 7437 4075 7436
      4067 7446 4066 7445 4066 7440 4063 7442
      4057 7453 4052 7450 4043 7494 4069 7500
      4082 7483 4088 7480 4098 7428 4092 7429
      4090 7427

$$

SFJ

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 17, 3:50 AM EDT	Rip Current Statement	PHI	Atlantic, Cape May, Monmouth, Ocean	17 hr
Jul 17, 3:54 AM EDT	Flash Flood Watch	PHI	Burlington, Camden, Gloucester, Hunterdon, Mercer, Middlesex and 6 more	19 hr
Jul 17, 1:50 PM EDT	Areal Flood Advisory	PHI	Sussex, Warren	80 min
Jul 17, 1:57 PM EDT	Severe Thunderstorm Warning	PHI	Sussex, Warren	32 min
Jul 17, 2:21 PM EDT	Special Weather Statement	PHI	Warren	24 min
Jul 17, 2:28 PM EDT	Special Weather Statement	PHI	Sussex	32 min
Jul 17, 2:44 PM EDT	Special Weather Statement	PHI	Sussex	31 min
Jul 17, 3:14 PM EDT	Excessive Heat Watch	PHI	Atlantic, Burlington, Cape May, Cumberland, Hunterdon, Middlesex and 7 more	24 hr
Jul 17, 6:22 PM EDT	Special Weather Statement	PHI	Sussex	38 min
Jul 17, 6:39 PM EDT	Severe Thunderstorm Warning	PHI	Morris, Sussex, Warren	51 min
Jul 17, 7:15 PM EDT	Severe Thunderstorm Warning	PHI	Gloucester, Salem	45 min
Jul 17, 7:16 PM EDT	Special Marine Warning	PHI		59 min
Jul 17, 7:27 PM EDT	Special Weather Statement	PHI	Hunterdon, Morris	48 min
Jul 17, 7:44 PM EDT	Severe Thunderstorm Warning	PHI	Atlantic, Cape May, Cumberland, Gloucester, Salem	46 min
Jul 17, 7:56 PM EDT	Special Weather Statement	PHI	Burlington, Camden, Gloucester	64 min

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.