Alert archive / New Jersey / Areal Flood Advisories in 2021

Areal Flood Advisory 82, NWS Philadelphia/Mount Holly

July 16, 2021Sussex County, New Jersey

NWS Philadelphia/Mount Holly issued this areal flood advisory at Jul 16, 2021, 5:01 PM EDT for Sussex County, New Jersey. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: Jul 16, 2021, 5:01 PM EDT (21:01 UTC)
Expired: Jul 16, 2021, 7:26 PM EDT
In force: 2 hr
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon

County Sussex County, NJ

The radar

The Philadelphia radar (KDIX), 145 km from the middle of the area, began a volume at 21:01 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, 9.0 hours before the alert went out and 167 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: 1044 J/kg
Mixed-layer CIN: -56 J/kg
Mixed-layer LCL: 994 m above ground
0-6 km bulk shear: 17 kt
0-1 km storm-relative helicity: 108 m²/s²
0-3 km storm-relative helicity: 105 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

501 
WGUS81 KPHI 162101
FLSPHI

Flood Advisory
National Weather Service Mount Holly NJ
501 PM EDT Fri Jul 16 2021

NJC037-170100-
/O.NEW.KPHI.FA.Y.0082.210716T2101Z-210717T0100Z/
/00000.N.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Sussex NJ-
501 PM EDT Fri Jul 16 2021

The National Weather Service in Mount Holly NJ has issued a

* Flood Advisory for...
  Northwestern Sussex County in northwestern New Jersey...

* Until 900 PM EDT.

* At 459 PM EDT, Doppler radar indicated heavy rain due to 
  thunderstorms. Up to one inch of rain has already fallen with 
  additional rainfall occurring. This will cause minor flooding in 
  the advisory area.

* Some locations that could experience flooding include...
  Hainesville.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

In hilly terrain there are hundreds of low water crossings which are
potentially dangerous in heavy rain. Do not attempt to cross flooded
roads. Find an alternate route.

A Flood Advisory means river or stream flows are elevated, or ponding
of water in urban or other areas is occurring or is imminent.

&&

LAT...LON 4119 7468 4118 7488 4120 7488 4121 7486
      4123 7487 4124 7486 4126 7485 4127 7469

$$

Robertson

1 follow-up statement

018 
WGUS81 KPHI 162326 RRB
FLSPHI

Flood Advisory
National Weather Service Mount Holly NJ
726 PM EDT Fri Jul 16 2021

NJC037-162336-
/O.CAN.KPHI.FA.Y.0082.000000T0000Z-210717T0100Z/
/00000.N.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Sussex NJ-
726 PM EDT Fri Jul 16 2021

...FLOOD ADVISORY IS CANCELLED FOR NORTHWESTERN SUSSEX COUNTY...

The heavy rain has ended. Flooding is no longer expected to pose a 
threat. Please continue to heed remaining road closures. Additional
showers and thunderstorms are possible through this evening.

LAT...LON 4119 7468 4118 7488 4120 7488 4121 7486
      4123 7487 4124 7486 4126 7485 4127 7469

$$

Robertson

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 16, 2:55 PM EDT	Areal Flood Advisory	PHI	Sussex	4 hr
Jul 16, 3:17 PM EDT	Flash Flood Watch	PHI	Atlantic, Burlington, Camden, Gloucester, Hunterdon, Mercer and 8 more	35 hr
Jul 16, 5:21 PM EDT	Flash Flood Warning	PHI	Sussex	2 hr
Jul 16, 5:25 PM EDT	Special Weather Statement	PHI	Sussex	35 min
Jul 16, 5:29 PM EDT	Severe Thunderstorm Warning	PHI	Sussex	46 min
Jul 16, 5:34 PM EDT	Areal Flood Advisory	PHI	Sussex, Warren	112 min
Jul 16, 6:10 PM EDT	Special Weather Statement	PHI	Warren	35 min
Jul 16, 6:14 PM EDT	Special Weather Statement	PHI	Sussex	31 min
Jul 16, 6:27 PM EDT	Areal Flood Advisory	PHI	Sussex	59 min
Jul 16, 6:46 PM EDT	Special Weather Statement	PHI	Warren	29 min
Jul 16, 7:10 PM EDT	Special Weather Statement	PHI	Warren	35 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.