Alert archive / New Jersey / Areal Flood Warnings in 2021

Areal Flood Warning 14, NWS Philadelphia/Mount Holly

August 11, 2021Morris County, Warren County, New Jersey

NWS Philadelphia/Mount Holly issued this areal flood warning at Aug 11, 2021, 10:54 PM EDT for Morris County, Warren County, New Jersey. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 11, 2021, 10:54 PM EDT (02:54 UTC)
Expired
Aug 12, 2021, 1:30 AM EDT
In force
3 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
None

Counties Morris County, NJ, Warren County, NJ

The radar

The Philadelphia radar (KDIX), 102 km from the middle of the area, began a volume at 02:58 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 00:00Z, 2.9 hours before the alert went out and 145 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-pSkew-T log-p diagram, Brookhaven, NY at 00:00Z on 2021-08-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1528 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Brookhaven, NY at 00:00Z on 2021-08-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 101 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
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
1528 J/kg
Mixed-layer CIN
-105 J/kg
Mixed-layer LCL
942 m above ground
0-6 km bulk shear
18 kt
0-1 km storm-relative helicity
101 m²/s²
0-3 km storm-relative helicity
96 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

430 
WGUS41 KPHI 120254
FLWPHI

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Flood Warning
National Weather Service Mount Holly NJ
1054 PM EDT Wed Aug 11 2021

NJC027-041-120530-
/O.NEW.KPHI.FA.W.0014.210812T0254Z-210812T0530Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Morris NJ-Warren NJ-
1054 PM EDT Wed Aug 11 2021

The National Weather Service in Mount Holly has issued a

* Flood Warning for...
  Morris County in northern New Jersey...
  East Central Warren County in northwestern New Jersey...

* Until 130 AM EDT.

* At 1054 PM EDT, the heaviest rain from earlier this evening has 
  diminished after bringing upwards of 3 inches of rainfall to the 
  area. The flash flood threat has ended but lingering standing 
  water, especially in lower lying areas, will continue to result in 
  flooding in spots before the water gradually recedes.



* Some locations that will experience flooding include...
  Morristown, Dover, Madison, Hopatcong, Florham Park, East Hanover, 
  Lincoln Park, Hackettstown, Boonton, Wharton, Rockaway, and Morris 
  Plains.

This includes the following highways...
	Interstate 80 in New Jersey between mile markers 25 and 48.
	Interstate 287 in New Jersey between mile markers 34 and 48.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4078 7495 4085 7500 4090 7498 4091 7472
      4090 7471 4092 7465 4094 7452 4093 7429
      4091 7427 4090 7428 4091 7433 4087 7434
      4086 7432 4082 7433 4080 7436 4078 7437
      4075 7463 4077 7486 4079 7489

$$

Fitzsimmons

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 11, 8:10 PM EDTSevere Thunderstorm WarningPHIHunterdon, Morris, Sussex, Warren35 min
Aug 12, 3:33 PM EDTSevere Thunderstorm WarningPHISussex, Warren57 min
Aug 12, 4:11 PM EDTSevere Thunderstorm WarningPHIMorris, Sussex, Warren34 min

Nearby

Areal Flood Warnings in New Jersey, 2021Every areal flood warning 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.