Alert archive / New Jersey / Flash Flood Warnings in 2021

Flash Flood Warning 77, NWS Philadelphia/Mount Holly

September 1, 20215 counties in New Jersey

NWS Philadelphia/Mount Holly issued this flash flood warning at Sep 1, 2021, 9:01 PM EDT for 5 counties in New Jersey. It was in force for 5 hr. 6 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
Sep 1, 2021, 9:01 PM EDT (01:01 UTC)
Expired
Sep 2, 2021, 1:38 AM EDT
In force
5 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
None

Counties Burlington County, NJ, Mercer County, NJ, Middlesex County, NJ, Monmouth County, NJ, Ocean County, NJ

The radar

The Philadelphia radar (KDIX), 48 km from the middle of the area, began a volume at 01:00 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
Sep 1, 9:31 PM EDTFLASH FLOOD1 W Hazlet, NJROUTE 35 CLOSED NEAR THE ROUTE 36 INTERSECTION FROM FLOODING. TIME BASED ON DISPATCH REPORT.
Sep 1, 9:32 PM EDTFLASH FLOOD1 Ese Hazlet, NJROUTE 35 CLOSED NEAR MILLER AVENUE FROM FLOODING. TIME BASED ON DISPATCH REPORT.
Sep 1, 9:45 PM EDTFLASH FLOODPort Monmouth, NJSTATE HIGHWAY 36 CLOSED AT MAIN STREET FROM FLOODING. TIME BASED ON DISPATCH REPORT.
Sep 1, 10:00 PM EDTFLASH FLOOD1 Se Hazlet, NJROUTE 35 CLOSED EAST OF BETHANY ROAD FROM FLASH FLOODING. TIME BASED ON NEARBY REPORTS AND RADAR.
Sep 1, 10:30 PM EDTFLASH FLOOD1 Wnw West Freehold, NJBUSINESS ROUTE 33 CLOSED BETWEEN CARDIGAN BAY LANE AND WEMROCK ROAD FROM FLOODING. TIME BASED ON DISPATCH REPORTS AND RADAR.
Sep 2, 12:14 AM EDTHEAVY RAIN 5.18Matawan, NJ

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, 1.0 hours before the alert went out and 133 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 2021-09-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 123 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 2021-09-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 279 square meters per square second.19395878Sfc1 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
123 J/kg
Mixed-layer CIN
-47 J/kg
Mixed-layer LCL
512 m above ground
0-6 km bulk shear
53 kt
0-1 km storm-relative helicity
279 m²/s²
0-3 km storm-relative helicity
456 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.2

Open this sounding in Storm Lab

The text

As transmitted.

771 
WGUS51 KPHI 020101
FFWPHI
NJC005-021-023-025-029-020545-
/O.NEW.KPHI.FF.W.0077.210902T0101Z-210902T0545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
901 PM EDT Wed Sep 1 2021

The National Weather Service in Mount Holly has issued a

* Flash Flood Warning for...
  Eastern Mercer County in central New Jersey...
  Monmouth County in central New Jersey...
  Southeastern Middlesex County in northern New Jersey...
  Northeastern Burlington County in southern New Jersey...
  Northern Ocean County in southern New Jersey...

* Until 145 AM EDT.

* At 901 PM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 and 3 inches of rain 
  have fallen. The expected rainfall rate is 0.5 to 1.5 inches in 1 
  hour. Flash flooding is ongoing or expected to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar.

  IMPACT...Flooding of small creeks and streams, urban areas,
           highways, streets, and underpasses as well as other
           drainage and low lying areas.

* Some locations that may experience flash flooding include...
  Long Branch, Asbury Park, Sandy Hook, Lakewood, Middletown, Old 
  Bridge, Jackson, Howell, East Brunswick, South Brunswick, 
  Marlboro, and Manalapan.

This includes the following highways...
	New Jersey Turnpike between exits 7 and 9.
	Interstate 295 in New Jersey between mile markers 54 and 59...and
	near mile marker 63.
	Interstate 195 in New Jersey between mile markers 1 and 34.
	Garden State Parkway between mile markers 97 and 121.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4039 7463 4038 7462 4040 7459 4040 7428
      4046 7425 4044 7421 4045 7417 4045 7416
      4046 7414 4040 7398 4048 7401 4042 7396
      4022 7396 4003 7433 4008 7476

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...0.5-1.5 INCHES IN 1 HOUR

$$

CMS
3 follow-up statements
070 
WGUS71 KPHI 020156
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
956 PM EDT Wed Sep 1 2021

NJC005-021-023-025-029-020545-
/O.CON.KPHI.FF.W.0077.000000T0000Z-210902T0545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Burlington NJ-Mercer NJ-Middlesex NJ-Monmouth NJ-Ocean NJ-
956 PM EDT Wed Sep 1 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 145 AM EDT THURSDAY 
FOR EASTERN MERCER, MONMOUTH, SOUTHEASTERN MIDDLESEX, NORTHEASTERN 
BURLINGTON, AND NORTHERN OCEAN COUNTIES...

At 956 PM EDT, local law enforcement reported flash flooding across 
the warned area. Several roads are closed in Keyport and Hazlet 
Township in Monmouth County. Between 1 and 4 inches of rain have 
fallen. The expected rainfall rate is 0.5 to 1.5 inches in 1 hour. 
Flash flooding is already occurring.

HAZARD...Life threatening flash flooding caused by heavy rain.

SOURCE...Law enforcement reported.

IMPACT...Life threatening flash flooding of creeks and streams,
         urban areas, highways, streets, and underpasses.

Some locations that may experience flash flooding include...
  Long Branch, Asbury Park, Sandy Hook, Lakewood, Middletown, Old 
  Bridge, Jackson, Howell, East Brunswick, South Brunswick, 
  Marlboro, and Manalapan.

This includes the following highways...
	New Jersey Turnpike between exits 7 and 9.
	Interstate 295 in New Jersey between mile markers 53 and 59...and
	near mile marker 63.
	Interstate 195 in New Jersey between mile markers 1 and 34.
	Garden State Parkway between mile markers 97 and 121.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4039 7463 4038 7462 4040 7459 4040 7428
      4046 7425 4044 7421 4045 7417 4045 7416
      4046 7414 4040 7398 4048 7401 4042 7396
      4022 7396 4003 7433 4008 7476

FLASH FLOOD...OBSERVED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
EXPECTED RAINFALL...0.5-1.5 INCHES IN 1 HOUR

$$

CMS
428 
WGUS71 KPHI 020309
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
1109 PM EDT Wed Sep 1 2021

NJC005-021-023-025-029-020545-
/O.CON.KPHI.FF.W.0077.000000T0000Z-210902T0545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Burlington NJ-Mercer NJ-Middlesex NJ-Monmouth NJ-Ocean NJ-
1109 PM EDT Wed Sep 1 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 145 AM EDT THURSDAY 
FOR EASTERN MERCER, MONMOUTH, SOUTHEASTERN MIDDLESEX, NORTHEASTERN 
BURLINGTON, AND NORTHERN OCEAN COUNTIES...

At 1109 PM EDT, local law enforcement reported flash flooding across 
the warned area. Several water rescues are ongoing in Keyport. 
Several roads are closed in southern Middlesex and northern Monmouth 
Counties. Avoid unnecessary travel in the warned area. Between 1 and 
4 inches of rain have fallen. Flash flooding is already occurring.

HAZARD...Life threatening flash flooding caused by heavy rain.

SOURCE...Law enforcement reported.

IMPACT...Life threatening flash flooding of creeks and streams,
         urban areas, highways, streets, and underpasses.

Some locations that may experience flash flooding include...
  Long Branch, Asbury Park, Sandy Hook, Lakewood, Middletown, Old 
  Bridge, Jackson, Howell, East Brunswick, South Brunswick, 
  Marlboro, and Manalapan.

This includes the following highways...
	New Jersey Turnpike between exits 7 and 9.
	Interstate 295 in New Jersey between mile markers 53 and 59...and
	near mile marker 63.
	Interstate 195 in New Jersey between mile markers 1 and 34.
	Garden State Parkway between mile markers 97 and 121.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4039 7463 4038 7462 4040 7459 4040 7428
      4046 7425 4044 7421 4045 7417 4045 7416
      4046 7414 4040 7398 4048 7401 4042 7396
      4022 7396 4003 7433 4008 7476

FLASH FLOOD...OBSERVED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

CMS
716 
WGUS71 KPHI 020538
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
138 AM EDT Thu Sep 2 2021

NJC005-021-023-025-029-020548-
/O.CAN.KPHI.FF.W.0077.000000T0000Z-210902T0545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Burlington NJ-Mercer NJ-Middlesex NJ-Monmouth NJ-Ocean NJ-
138 AM EDT Thu Sep 2 2021

...FLASH FLOOD WARNING FOR EASTERN MERCER, MONMOUTH, SOUTHEASTERN 
MIDDLESEX, NORTHEASTERN BURLINGTON, AND NORTHERN OCEAN COUNTIES HAS 
BEEN REPLACED WITH A FLOOD WARNING...

Please continue to heed road closures.

LAT...LON 4039 7463 4038 7462 4040 7459 4040 7428
      4046 7425 4044 7421 4045 7417 4045 7416
      4046 7414 4040 7398 4048 7401 4042 7396
      4022 7396 4003 7433 4008 7476

$$

CMS

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 1, 8:02 PM EDTFlash Flood Warning EmergencyCatastrophic damage threatPHIMiddlesex, Morris, Somerset5 hr
Sep 1, 9:43 PM EDTRiver Flood WarningPHIMercer33 hr
Sep 1, 10:05 PM EDTFlash Flood Warning Considerable damage threatPHIMorris, Somerset4 hr
Sep 1, 10:23 PM EDTCoastal Flood StatementPHIOcean13 hr
Sep 1, 10:24 PM EDTFlash Flood WarningPHIBurlington, Camden, Gloucester4 hr
Sep 1, 10:29 PM EDTRiver Flood WarningPHIHunterdon, Mercer49 hr
Sep 1, 10:32 PM EDTRiver Flood WarningPHIMercer31 hr
Sep 1, 10:35 PM EDTRiver Flood WarningPHIBergen, Morris, Passaic30 hr
Sep 1, 10:37 PM EDTRiver Flood WarningPHIMorris, Passaic41 hr
Sep 1, 10:38 PM EDTRiver Flood WarningPHIMorris, Somerset21 days
Sep 1, 10:47 PM EDTAreal Flood WarningPHIWarren23 hr
Sep 1, 10:52 PM EDTAreal Flood WarningPHIHunterdon, Warren12 hr
Sep 2, 12:01 AM EDTAreal Flood WarningPHIHunterdon, Morris, Sussex, Warren40 hr
Sep 2, 12:28 AM EDTAreal Flood AdvisoryPHIAtlantic, Burlington, Camden, Gloucester3 hr
Sep 2, 12:31 AM EDTAreal Flood AdvisoryPHIMonmouth, Ocean2 hr
Sep 2, 1:38 AM EDTAreal Flood WarningPHIBurlington, Mercer, Middlesex, Monmouth, Ocean4 hr
Sep 2, 1:52 AM EDTAreal Flood WarningPHIMorris, Somerset13 hr
Sep 2, 2:23 AM EDTAreal Flood WarningPHIBurlington, Camden, Gloucester, Salem9 hr
Sep 2, 2:29 AM EDTAreal Flood WarningPHIBurlington, Camden, Gloucester5 hr
Sep 2, 3:52 AM EDTAreal Flood WarningPHIHunterdon, Mercer, Morris, Somerset, Warren8 hr
Sep 2, 3:53 AM EDTAreal Flood WarningPHIHunterdon, Mercer, Middlesex, Morris, Somerset8 hr
Sep 2, 4:00 AM EDTRiver Flood WarningPHIMorris48 hr
Sep 2, 4:45 AM EDTRiver Flood WarningPHIHunterdon, Mercer37 hr
Sep 2, 4:45 AM EDTRiver Flood WarningPHIHunterdon, Warren37 hr
Sep 2, 4:45 AM EDTRiver Flood WarningPHIHunterdon37 hr
Sep 2, 4:45 AM EDTRiver Flood WarningPHIHunterdon33 hr
Sep 2, 4:45 AM EDTRiver Flood WarningPHIHunterdon, Mercer34 hr
Sep 2, 4:45 AM EDTRiver Flood WarningPHISussex, Warren5 hr
Sep 2, 6:05 AM EDTCoastal Flood WarningPHIBurlington, Camden, Gloucester, Mercer6 hr
Sep 2, 1:20 PM EDTAreal Flood WarningPHIMiddlesex21 hr
Sep 2, 6:44 PM EDTCoastal Flood AdvisoryPHIBurlington, Camden, Gloucester7 hr

Nearby

Flash Flood Warnings in New Jersey, 2021Every flash 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.