Alert archive / New Jersey / Flash Flood Warnings in 2024

Flash Flood Warning 59, NWS Philadelphia/Mount Holly

August 18, 2024Burlington County, Camden County, Mercer County, New Jersey

NWS Philadelphia/Mount Holly issued this flash flood warning at Aug 18, 2024, 4:41 AM EDT for Burlington County, Camden County, Mercer County, New Jersey. It was in force for 2 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 18, 2024, 4:41 AM EDT (08:41 UTC)
Expired
Aug 18, 2024, 6:57 AM EDT
In force
2 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
None

Counties Burlington County, NJ, Camden County, NJ, Mercer County, NJ

The radar

The Philadelphia radar (KDIX), 28 km from the middle of the area, began a volume at 08:41 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, 8.7 hours before the alert went out and 172 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 2024-08-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 2024-08-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 83 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
735 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
83 m²/s²
0-3 km storm-relative helicity
106 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

930 
WGUS51 KPHI 180841
FFWPHI
NJC005-007-021-181245-
/O.NEW.KPHI.FF.W.0059.240818T0841Z-240818T1245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
441 AM EDT Sun Aug 18 2024

The National Weather Service in Mount Holly has issued a

* Flash Flood Warning for...
  Southeastern Mercer County in central New Jersey...
  Northwestern Burlington County in southern New Jersey...
  Central Camden County in southern New Jersey...

* Until 845 AM EDT.

* At 441 AM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1.5 and 2.5 inches of 
  rain have fallen. The expected rainfall rate is 1 to 2 inches in 1 
  hour. Additional rainfall amounts of 0.5 to 1 inch are possible in 
  the warned area. 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...
  Evesham, Voorhees, Medford, Lindenwold, Lumberton, Mount Holly, 
  Berlin, Bordentown, Allentown, Jacksonville, Columbus and Jobstown.

This includes the following highways...
	Interstate 295 in New Jersey between mile markers 55 and 56.
	New Jersey Turnpike between exits 7 and 8.
	Interstate 195 in New Jersey between mile markers 5 and 8.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

Be aware of your surroundings and do not drive on flooded roads.

&&

LAT...LON 4024 7451 4019 7456 4018 7459 4019 7460
      4018 7461 4015 7459 3978 7490 3983 7499
      4027 7459

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL RATE...1-2 INCHES IN 1 HOUR

$$

RCM
2 follow-up statements
650 
WGUS71 KPHI 181003
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
603 AM EDT Sun Aug 18 2024

NJC007-181013-
/O.CAN.KPHI.FF.W.0059.000000T0000Z-240818T1245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Camden NJ-
603 AM EDT Sun Aug 18 2024

...FLASH FLOOD WARNING IS CANCELLED FOR CENTRAL CAMDEN COUNTY...

Flooding is no longer expected to pose a threat. Please continue to 
heed remaining road closures.

A Flood Watch remains in effect until 200 AM EDT Monday for portions 
of northern Delaware, New Jersey, and Pennsylvania.

&&

LAT...LON 4000 7476 4003 7481 4027 7459 4024 7451
      4022 7454 4019 7456 4018 7459 4019 7460
      4018 7461 4015 7459 3997 7474

$$

NJC005-021-181245-
/O.CON.KPHI.FF.W.0059.000000T0000Z-240818T1245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Burlington NJ-Mercer NJ-
603 AM EDT Sun Aug 18 2024

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 845 AM EDT THIS 
MORNING FOR SOUTHEASTERN MERCER AND NORTH CENTRAL BURLINGTON 
COUNTIES...

At 603 AM EDT, Doppler radar indicated thunderstorms producing heavy 
rain across the warned area. Between 2 and 4 inches of rain have 
fallen. The expected rainfall rate is 1 to 2 inches in 1 hour. 
Additional rainfall amounts of 0.5 to 1 inch are possible in the 
warned area. 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...
  Bordentown, Allentown, Crosswicks, Georgetown, Columbus, Jobstown, 
  Mercerville-Hamilton Square, Jacksonville, Windsor and 
  Yardville-Groveville.

This includes the following highways...
	Interstate 295 in New Jersey between mile markers 55 and 56.
	New Jersey Turnpike between exits 7 and 8.
	Interstate 195 in New Jersey between mile markers 5 and 8.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

Be aware of your surroundings and do not drive on flooded roads.

&&

LAT...LON 4000 7476 4003 7481 4027 7459 4024 7451
      4022 7454 4019 7456 4018 7459 4019 7460
      4018 7461 4015 7459 3997 7474

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL RATE...1-2 INCHES IN 1 HOUR

$$

RCM
542 
WGUS71 KPHI 181057
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
657 AM EDT Sun Aug 18 2024

NJC005-021-181107-
/O.CAN.KPHI.FF.W.0059.000000T0000Z-240818T1245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Burlington NJ-Mercer NJ-
657 AM EDT Sun Aug 18 2024

...FLASH FLOOD WARNING IS CANCELLED FOR SOUTHEASTERN MERCER AND 
NORTH CENTRAL BURLINGTON COUNTIES...

Flood waters have receded. The heavy rain has ended. Flooding is no 
longer expected to pose a threat. Please continue to heed remaining 
road closures.

A Flood Watch remains in effect until 200 AM EDT Monday for portions 
of northern Delaware, New Jersey, and Pennsylvania.

&&

LAT...LON 4000 7476 4003 7481 4027 7459 4024 7451
      4022 7454 4019 7456 4018 7459 4019 7460
      4018 7461 4015 7459 3997 7474

$$

RCM

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 18, 3:09 AM EDTFlash Flood WarningPHIBurlington, Camden93 min
Aug 18, 2:17 PM EDTSpecial Marine WarningPHI58 min
Aug 18, 2:42 PM EDTSpecial Marine WarningPHI93 min
Aug 18, 3:55 PM EDTSpecial Marine WarningPHI95 min
Aug 18, 4:04 PM EDTSevere Thunderstorm WarningPHIWarren41 min
Aug 18, 4:41 PM EDTSevere Thunderstorm WarningPHISussex, Warren34 min
Aug 18, 4:56 PM EDTFlash Flood WarningPHIWarren6 hr
Aug 18, 5:10 PM EDTSevere Thunderstorm WarningPHIHunterdon, Morris, Warren29 min
Aug 18, 5:21 PM EDTSevere Thunderstorm WarningPHIBurlington, Camden39 min
Aug 18, 5:31 PM EDTFlash Flood WarningPHIHunterdon, Warren6 hr
Aug 18, 5:38 PM EDTFlash Flood WarningPHISussex, Warren4 hr
Aug 18, 5:47 PM EDTSevere Thunderstorm WarningPHIMorris, Sussex43 min
Aug 18, 5:47 PM EDTSevere Thunderstorm WarningPHIBurlington, Mercer, Middlesex, Monmouth58 min
Aug 18, 5:51 PM EDTSevere Thunderstorm WarningPHIMorris, Somerset24 min
Aug 18, 5:59 PM EDTSevere Thunderstorm WarningPHIMorris, Sussex18 min
Aug 18, 6:01 PM EDTFlash Flood WarningPHIHunterdon, Morris, Somerset, Sussex, Warren6 hr
Aug 18, 6:24 PM EDTSevere Thunderstorm WarningPHIMiddlesex, Morris, Somerset66 min
Aug 18, 6:36 PM EDTFlash Flood WarningPHIMorris, Somerset5 hr

Nearby

Flash Flood Warnings in New Jersey, 2024Every flash flood warning in 2024

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.