Alert archive / New Jersey / Areal Flood Advisories in 2021

Areal Flood Advisory 87, NWS Philadelphia/Mount Holly

July 17, 2021Middlesex County, New Jersey

NWS Philadelphia/Mount Holly issued this areal flood advisory at Jul 17, 2021, 3:38 PM EDT for Middlesex County, New Jersey. It was in force for 40 min.

The area

The outline as issued.

The facts

Issued: Jul 17, 2021, 3:38 PM EDT (19:38 UTC)
Expired: Jul 17, 2021, 4:18 PM EDT
In force: 40 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon

County Middlesex County, NJ

The radar

The Philadelphia radar (KDIX), 63 km from the middle of the area, began a volume at 19:41 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.

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 7.6 hours before the alert went out and 126 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: 1203 J/kg
Mixed-layer CIN: -55 J/kg
Mixed-layer LCL: 1054 m above ground
0-6 km bulk shear: 24 kt
0-1 km storm-relative helicity: 35 m²/s²
0-3 km storm-relative helicity: 46 m²/s²
Significant tornado parameter: 0.2
Supercell composite: 1.0

Open this sounding in Storm Lab

The text

As transmitted.

540 
WGUS81 KPHI 171938
FLSPHI

Flood Advisory
National Weather Service Mount Holly NJ
338 PM EDT Sat Jul 17 2021

NJC023-172145-
/O.NEW.KPHI.FA.Y.0087.210717T1938Z-210717T2145Z/
/00000.N.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Middlesex NJ-
338 PM EDT Sat Jul 17 2021

The National Weather Service in Mount Holly has issued a

* Flood Advisory for...
  Northeastern Middlesex County in northern New Jersey...

* Until 545 PM EDT.

* At 338 PM EDT, Doppler radar indicated heavy rain due to 
  thunderstorms. Minor flooding is ongoing or expected to begin 
  shortly in the advisory area. Between 0.5 and 1 inch of rain has 
  already fallen in spots with an additional inch possible.

* Some locations that may experience flooding include...
  New Brunswick, Perth Amboy, Edison, Old Bridge, East Brunswick, 
  Sayreville, Carteret, Colonia, Woodbridge, South River, Metuchen, 
  and Fords.

This includes the following highways...
	New Jersey Turnpike between exits 11 and 13.
	Interstate 287 in New Jersey between mile markers 0 and 4.
	Garden State Parkway between mile markers 121 and 134.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Be aware of your surroundings and do not drive on flooded roads.

&&

LAT...LON 4042 7440 4060 7440 4061 7431 4059 7429
      4060 7422 4059 7420 4056 7422 4055 7425
      4052 7425 4050 7426 4050 7428 4049 7429
      4049 7427 4048 7427 4047 7427 4046 7426
      4045 7422 4043 7425 4042 7425

$$

Iovino

1 follow-up statement

445 
WGUS81 KPHI 172018
FLSPHI

Flood Advisory
National Weather Service Mount Holly NJ
418 PM EDT Sat Jul 17 2021

NJC023-172028-
/O.CAN.KPHI.FA.Y.0087.000000T0000Z-210717T2145Z/
/00000.N.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Middlesex NJ-
418 PM EDT Sat Jul 17 2021

...FLOOD ADVISORY IS CANCELLED FOR NORTHEASTERN MIDDLESEX COUNTY...

The heavy rain has ended for the time being. Additional heavy rain 
is expected this evening into tonight. Please continue to heed 
remaining road closures.

LAT...LON 4042 7440 4060 7440 4061 7431 4059 7429
      4060 7422 4059 7420 4056 7422 4055 7425
      4052 7425 4050 7426 4050 7428 4049 7429
      4049 7427 4048 7427 4047 7427 4046 7426
      4045 7422 4043 7425 4042 7425

$$

Iovino

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 17, 12:55 PM EDT	Special Weather Statement	PHI	Hunterdon	50 min
Jul 17, 1:05 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Mercer	40 min
Jul 17, 1:31 PM EDT	Areal Flood Advisory	PHI	Hunterdon	97 min
Jul 17, 1:50 PM EDT	Special Marine Warning	PHI		40 min
Jul 17, 1:56 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Morris, Somerset, Warren	36 min
Jul 17, 2:02 PM EDT	Areal Flood Advisory	PHI	Monmouth, Ocean	92 min
Jul 17, 2:56 PM EDT	Severe Thunderstorm Warning	PHI	Middlesex, Somerset	49 min
Jul 17, 3:06 PM EDT	Severe Thunderstorm Warning	PHI	Warren	39 min
Jul 17, 3:09 PM EDT	Tornado Warning	PHI	Middlesex	21 min
Jul 17, 3:51 PM EDT	Severe Thunderstorm Warning	PHI	Middlesex	24 min
Jul 17, 4:55 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Somerset	50 min
Jul 17, 5:13 PM EDT	Areal Flood Advisory	PHI	Hunterdon	4 hr
Jul 17, 5:19 PM EDT	Tornado Warning	PHI	Hunterdon	14 min
Jul 17, 5:25 PM EDT	Flash Flood Warning	PHI	Hunterdon	6 hr
Jul 17, 5:30 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Warren	19 min
Jul 17, 5:52 PM EDT	Areal Flood Advisory	PHI	Somerset	2 hr
Jul 17, 6:02 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Mercer, Somerset	43 min
Jul 17, 6:15 PM EDT	Flash Flood Warning	PHI	Morris, Somerset	5 hr
Jul 17, 6:39 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Mercer, Middlesex, Morris, Somerset	51 min
Jul 17, 6:51 PM EDT	Severe Thunderstorm Warning	PHI	Burlington	39 min
Jul 17, 6:59 PM EDT	Small Craft Advisory	PHI		7 hr
Jul 17, 7:01 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Somerset	44 min
Jul 17, 7:12 PM EDT	Areal Flood Advisory	PHI	Mercer, Somerset	3 hr
Jul 17, 7:26 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Mercer, Middlesex, Morris, Somerset	49 min

Nearby

Areal Flood Advisories in New Jersey, 2021 Every areal flood advisory in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.