Alert archive / New Jersey / Areal Flood Warnings in 2021

Areal Flood Warning 26, NWS Philadelphia/Mount Holly

August 23, 2021Somerset County, New Jersey

NWS Philadelphia/Mount Holly issued this areal flood warning at Aug 23, 2021, 5:22 AM EDT for Somerset County, New Jersey. It was in force for 9 hr. 2 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, 5:22 AM EDT (09:22 UTC)
Expired
Aug 23, 2021, 2:08 PM EDT
In force
9 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
None

County Somerset County, NJ

The radar

The Philadelphia radar (KDIX), 81 km from the middle of the area, began a volume at 09:25 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, 6:15 AM EDTFLOOD4 Ese Oldwick, NJTHE GAUGE ON THE LAMINGTON (BLACK) RIVER AT BURNT MILLS (BTMN4) REACHED FLOOD STAGE AND IS CURRENTLY IN MODERATE FLOOD.
Aug 23, 8:53 AM EDTHEAVY RAIN 4.793 Nw Bridgewater, NJASOS STATION KSMQ SOMERVILLE.

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, 9.4 hours before the alert went out and 155 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°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.

398 
WGUS41 KPHI 230922
FLWPHI

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

NJC035-231600-
/O.NEW.KPHI.FA.W.0026.210823T0922Z-210823T1600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Somerset NJ-
522 AM EDT Mon Aug 23 2021

The National Weather Service in Mount Holly has issued a

* Flood Warning for...
  Central Somerset County in northern New Jersey...

* Until noon EDT Monday.

* At 522 AM EDT, gauge reports indicated minor stream flooding in 
  the Bedminster and Branchburg areas. The minor flooding should 
  continue this morning.


* Some locations that will experience flooding include...
  Bedminster and Branchburg

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4067 7467 4061 7465 4061 7470 4067 7471

$$

Iovino
2 follow-up statements
763 
WGUS41 KPHI 231436
FLWPHI

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Flood Warning
National Weather Service Mount Holly NJ
1036 AM EDT Mon Aug 23 2021

NJC035-232000-
/O.EXT.KPHI.FA.W.0026.000000T0000Z-210823T2000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Somerset NJ-
1036 AM EDT Mon Aug 23 2021

The National Weather Service in Mount Holly has extended the

* Flood Warning for...
  Central Somerset County in northern New Jersey...

* Until 400 PM EDT.

* At 1036 AM EDT, gauge reports indicated stream flooding in the 
  Bedminster and Branchburg areas. The flooding will continue into 
  the afternoon.

* Some locations that will experience flooding include...
  Bedminster and Branchburg

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4067 7467 4061 7465 4061 7470 4067 7471

$$

Kruzdlo
358 
WGUS81 KPHI 231808
FLSPHI

Flood Statement
National Weather Service Mount Holly NJ
208 PM EDT Mon Aug 23 2021

NJC035-231818-
/O.CAN.KPHI.FA.W.0026.000000T0000Z-210823T2000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Somerset NJ-
208 PM EDT Mon Aug 23 2021

...FLOOD WARNING IS CANCELLED FOR CENTRAL SOMERSET COUNTY...

Flood waters are receding. Please continue to heed remaining road 
closures.

LAT...LON 4067 7467 4061 7465 4061 7470 4067 7471

$$

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, 3:25 AM EDTAreal Flood WarningPHIMorris8 hr
Aug 23, 4:10 AM EDTRiver Flood WarningPHIMorris41 hr
Aug 23, 5:07 AM EDTAreal Flood WarningPHIWarren21 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.