Alert archive / New Jersey / Areal Flood Warnings in 2021

Areal Flood Warning 24, NWS Philadelphia/Mount Holly

August 23, 2021Morris County, New Jersey

NWS Philadelphia/Mount Holly issued this areal flood warning at Aug 23, 2021, 3:25 AM EDT for Morris County, New Jersey. It was in force for 8 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
Aug 23, 2021, 3:25 AM EDT (07:25 UTC)
Expired
Aug 23, 2021, 11:49 AM EDT
In force
8 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
None

County Morris County, NJ

The radar

The Philadelphia radar (KDIX), 97 km from the middle of the area, began a volume at 07:25 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

TimeReportWhereRemark
Aug 23, 8:45 AM EDTHEAVY RAIN 4.761 Nw Florham Park, NJMESONET STATION MSTN4 1.4 NW FLORHAM PARK.
Aug 23, 9:26 AM EDTHEAVY RAIN 4.33Morris Plains, NJMESONET STATION FW7545 MORRIS PLAINS.
Aug 23, 9:28 AM EDTHEAVY RAIN 6.47Whippany, NJMESONET STATION FW7566 WHIPPANY.
Aug 23, 9:35 AM EDTHEAVY RAIN 4.062 Ene Morristown, NJMESONET STATION MRRBD 1 NNE MORRIS TWP.
Aug 23, 9:35 AM EDTHEAVY RAIN 4.21Whippany, NJMESONET STATION WHPPN WHIPPANY (MEMORIAL).

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, 7.4 hours before the alert went out and 132 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 2021-08-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 59 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Brookhaven, NY at 00:00Z on 2021-08-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -22 square meters per square second.193958Sfc1 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
59 J/kg
Mixed-layer CIN
-168 J/kg
Mixed-layer LCL
610 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
-22 m²/s²
0-3 km storm-relative helicity
-66 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.0

Open this sounding in Storm Lab

The text

As transmitted.

375 
WGUS41 KPHI 230725
FLWPHI

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Flood Warning
National Weather Service Mount Holly NJ
325 AM EDT Mon Aug 23 2021

NJC027-231600-
/O.NEW.KPHI.FA.W.0024.210823T0725Z-210823T1600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Morris NJ-
325 AM EDT Mon Aug 23 2021

The National Weather Service in Mount Holly has issued a

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

* Until noon EDT Monday.

* At 325 AM EDT, gauge reports indicated minor flooding along the 
  Whippany River in the Morristown area.  The minor flooding is 
  expected to continue through the morning hours.

* Some locations that may experience flooding include...
  Morristown, East Hanover, Morris Plains, and Hanover Township.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Motorists should not attempt to drive around barricades or drive 
cars through flooded areas.

&&

LAT...LON 4079 7450 4084 7450 4084 7441 4085 7437
      4082 7436 4079 7439

$$

Iovino
1 follow-up statement
531 
WGUS81 KPHI 231549
FLSPHI

Flood Statement
National Weather Service Mount Holly NJ
1149 AM EDT Mon Aug 23 2021

NJC027-231559-
/O.CAN.KPHI.FA.W.0024.000000T0000Z-210823T1600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Morris NJ-
1149 AM EDT Mon Aug 23 2021

...FLOOD WARNING IS CANCELLED FOR EAST CENTRAL MORRIS COUNTY...

Although the Whippany River continues to run high, water levels have 
fallen below flood stage. Please continue to heed any remaining road 
closures until they are reopened.

LAT...LON 4079 7450 4084 7450 4084 7441 4085 7437
      4082 7436 4079 7439

$$

Kruzdlo

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 22, 8:11 PM EDTAreal Flood AdvisoryPHIWarren6 hr
Aug 22, 8:47 PM EDTFlash Flood WarningPHISussex, Warren6 hr
Aug 22, 11:27 PM EDTAreal Flood WarningPHIMiddlesex29 hr
Aug 23, 2:09 AM EDTRiver Flood WarningPHIMorris, Passaic17 hr
Aug 23, 4:10 AM EDTRiver Flood WarningPHIMorris41 hr
Aug 23, 5:07 AM EDTAreal Flood WarningPHIWarren21 hr
Aug 23, 5:22 AM EDTAreal Flood WarningPHISomerset9 hr
Aug 23, 5:44 AM EDTAreal Flood WarningPHIHunterdon7 hr
Aug 23, 7:20 AM EDTRiver Flood WarningPHIHunterdon, Somerset7 hr
Aug 23, 7:47 AM EDTRiver Flood WarningPHIMorris, Passaic13 hr
Aug 23, 8:36 AM EDTAreal Flood WarningPHISomerset9 hr
Aug 23, 8:42 AM EDTRiver Flood WarningPHIMiddlesex, Somerset21 hr
Aug 23, 11:22 AM EDTRiver Flood WarningPHIMiddlesex, Somerset16 hr
Aug 23, 11:32 AM EDTRiver Flood WarningPHIEssex, Morris, Passaic5 days
Aug 23, 11:58 AM EDTRiver Flood WarningPHISomerset15 hr
Aug 23, 12:19 PM EDTRiver Flood WarningPHIBurlington33 hr
Aug 23, 12:51 PM EDTCoastal Flood StatementPHIOcean3 hr
Aug 23, 2:26 PM EDTAreal Flood WarningPHISussex14 hr
Aug 23, 2:26 PM EDTSpecial Weather StatementPHIOcean49 min
Aug 23, 3:12 PM EDTSpecial Weather StatementPHIOcean33 min
Aug 23, 3:15 PM EDTSevere Thunderstorm WarningPHIOcean45 min
Aug 23, 3:18 PM EDTSpecial Marine WarningPHI57 min
Aug 23, 3:38 PM EDTRiver Flood WarningPHIEssex, Morris, Passaic48 hr
Aug 23, 4:47 PM EDTSpecial Weather StatementPHIAtlantic28 min
Aug 23, 4:50 PM EDTSpecial Marine WarningPHI55 min
Aug 23, 5:13 PM EDTSpecial Weather StatementPHICamden32 min
Aug 23, 5:39 PM EDTSpecial Marine WarningPHI33 min
Aug 23, 6:46 PM EDTSpecial Marine WarningPHI64 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.