Alert archive / New Jersey / Flash Flood Warnings in 2021
Flash Flood Warning 53, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this flash flood warning at Aug 22, 2021, 5:36 AM EDT for 4 counties in New Jersey. It was in force for 5 hr. 40 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 22, 2021, 5:36 AM EDT (09:36 UTC)
- Expired
- Aug 22, 2021, 11:00 AM EDT
- In force
- 5 hr
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
- Damage threat
- Considerable
- Flood severity
- None
Counties Mercer County, NJ, Middlesex County, NJ, Monmouth County, NJ, Somerset County, NJ
The radar
The Philadelphia radar (KDIX), 37 km from the middle of the area, began a volume at 09:38 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
| Time | Report | Where | Remark |
|---|---|---|---|
| Aug 22, 5:39 AM EDT | FLASH FLOOD | 1 Se Dayton, NJ | U.S. HIGHWAY 130 CLOSED FROM FLOODING BETWEEN GEORGES ROAD AND DEANS RHODE HALL ROAD. TIME BASED ON DISPATCH REPORT. |
| Aug 22, 5:40 AM EDT | FLASH FLOOD | 1 Wnw East Windsor Twp, NJ | FLOODING AND ROAD CLOSURES IN THE LOCUST CORNER AREA. TIME BASED ON DISPATCH REPORT. |
| Aug 22, 5:45 AM EDT | FLASH FLOOD | Jamesburg, NJ | SEVERE FLASH FLOODING OCCURRING. NUMEROUS ROADS CLOSED AND RESIDENCE FLOODING ONGOING. |
| Aug 22, 6:00 AM EDT | FLASH FLOOD | Helmetta, NJ | SEVERAL WATER RESCUES VIA BOAT IN HELMETTA. RESIDENCES EVACUATED FROM FLOODING. TIME BASED ON NEARBY DISPATCH REPORTS AND SOCIAL MEDIA POSTS. |
| Aug 22, 6:06 AM EDT | HEAVY RAIN 6.5 | Cranbury, NJ | AS OF 6 AM. SPOTTER REPORTED BASEMENT FLOODING. |
| Aug 22, 6:10 AM EDT | FLASH FLOOD | 1 E Plainsboro Township, NJ | VEHICLE STUCK IN WATER AND WATER RESCUE ON WOODLAND DRIVE. TIME BASED ON DISPATCH REPORT. |
| Aug 22, 6:10 AM EDT | FLASH FLOOD | 1 Sw Cranbury, NJ | SEVERAL WATER RESCUES IN PROGRESS IN CRANBURY. TIME BASED ON DISPATCH REPORTS. |
| Aug 22, 6:15 AM EDT | FLASH FLOOD | 1 Nne Windsor, NJ | FLOODING IN THE HANKINS ROAD AND WOODLAND DRIVE AREAS. WATER RESCUES IN PROGRESS. TIME BASED ON DISPATCH REPORTS. |
| Aug 22, 6:15 AM EDT | FLASH FLOOD | Monmmouth Junction, NJ | WATER RESCUES IN PROGRESS ON RIDGE ROAD. TIME BASED ON DISPATCH REPORTS. |
| Aug 22, 6:20 AM EDT | FLASH FLOOD | 1 S Rocky Hill, NJ | ROAD FLOODING AND CLOSURES NEAR THE MILLSTONE RIVER IN ROCKY HILL AND PRINCETON. TIME BASED ON DISPATCH REPORT. |
| Aug 22, 6:25 AM EDT | FLASH FLOOD | 1 S East Windsor Twp, NJ | WATER RESCUE NEAR THE INTERSECTION OF MERCER STREET AND AIRPORT ROAD. TIME BASED ON DISPATCH REPORT. |
| Aug 22, 6:27 AM EDT | FLASH FLOOD | East Windsor Twp, NJ | U.S. HIGHWAY 130 CLOSED SOUTH OF PRINCETON-HIGHTSTOWN ROAD FROM FLOODING. TIME BASED ON DISPATCH REPORT. |
| Aug 22, 6:47 AM EDT | HEAVY RAIN 8.28 | Cranbury, NJ | AS OF 6:45 AM. SPOTTER REPORTED BASEMENT FLOODING. |
| Aug 22, 6:49 AM EDT | FLASH FLOOD | 1 S Heathcote, NJ | FLOODING ON U.S. HIGHWAY 1 NEAR RAYMOND ROAD. CLOSURES IN PLACE. |
| Aug 22, 6:50 AM EDT | FLASH FLOOD | 1 Nnw East Windsor Twp, NJ | WATER RESCUE ON OLD TRENTON ROAD. TIME BASED ON DISPATCH REPORT. |
| Aug 22, 6:55 AM EDT | FLASH FLOOD | 2 E Plainsboro Township, NJ | WATER RESCUE ON DEY ROAD. TIME BASED ON DISPATCH REPORT. |
| Aug 22, 7:00 AM EDT | FLASH FLOOD | 1 Sse Princeton, NJ | THE MILLSTONE RIVER WAS FLOODING, CAUSING INUNDATION OF SEVERAL ROADS TRAVERSING IT IN WEST WINDSOR TWP. TIME ESTIMATED BASED ON NEARBY DISPATCH REPORTS AND SOCIAL MEDIA POSTS. |
| Aug 22, 7:00 AM EDT | HEAVY RAIN 5.12 | 2 Wsw East Windsor Twp, NJ | CO-OP OBSERVER STATION HGTN4 1.9 NE WINDSOR. |
| Aug 22, 7:00 AM EDT | HEAVY RAIN 7.5 | Plainsboro Township, NJ | |
| Aug 22, 7:08 AM EDT | HEAVY RAIN 5.12 | 1 Wsw East Windsor Twp, NJ | |
| Aug 22, 7:15 AM EDT | FLASH FLOOD | Jamesburg, NJ | WATER INUNDATING RAILROAD AVENUE AND FORSGATE DRIVE WITH WATER IN RESIDENCES AND VEHICLES STRANDED. |
| Aug 22, 7:15 AM EDT | FLASH FLOOD | Jamesburg, NJ | RESIDENCES FLOODED AND OCCUPANTS EVACUATED NEAR MANALAPAN BROOK. |
| Aug 22, 7:30 AM EDT | FLASH FLOOD | 1 S Jamesburg, NJ | WIDESPREAD FLOODING IN MONROE TOWNSHIP. SEVERAL ROADS ARE CLOSED AND VEHICLES ARE STRANDED IN WATER. |
| Aug 22, 7:30 AM EDT | FLASH FLOOD | Cranbury, NJ | WATER RESCUE ON SOUTH RIVER ROAD AND PROSPECT PLAINS ROAD. TIME BASED ON DISPATCH REPORT. |
| Aug 22, 7:30 AM EDT | FLASH FLOOD | Windsor, NJ | U.S. HIGHWAY 130 CLOSED AT CHURCH ROAD FROM FLOODING. TIME BASED ON DISPATCH REPORTS. |
| Aug 22, 7:45 AM EDT | FLASH FLOOD | 1 Sw Helmetta, NJ | MAIN STREET CLOSED NEAR HELMETTA AVENUE FROM FLOODING. |
| Aug 22, 7:46 AM EDT | FLASH FLOOD | Hightstown, NJ | FLOODING ON STATE HIGHWAY 33 EAST OF MAIN STREET WITH THE ROAD CLOSED. |
| Aug 22, 8:00 AM EDT | FLASH FLOOD | 2 Ene Cranbury, NJ | OVER 150 RESIDENTS WERE RESCUED OR EVACUATED BY BOAT IN MIDDLESEX COUNTY, NOTABLY IN THE JAMESBURG AND ROSSMOOR AREAS. TIME BASED ON DISPATCH REPORT AND SOCIAL MEDIA POSTS. |
| Aug 22, 8:21 AM EDT | FLASH FLOOD | 2 E Twin Rivers, NJ | FLOODING ON STATE HIGHWAY 33 EAST OF APPLEGARTH ROAD. ALL LANES CLOSED. TIME BASED ON DISPATCH REPORT. |
| Aug 22, 8:30 AM EDT | FLASH FLOOD | 2 Se Dayton, NJ | HERROD BOULEVARD CLOSED FROM FLOODING WITH SEVERAL WATER RESCUES AND STRANDED VEHICLES. |
| Aug 22, 8:33 AM EDT | HEAVY RAIN 4.24 | 1 Nw Princeton Junction, NJ | COCORAHS STATION NJ-MC-56 WEST WINDSOR TWP 2.6 N. |
| Aug 22, 8:49 AM EDT | HEAVY RAIN 4.14 | Hamilton Square, NJ | |
| Aug 22, 9:08 AM EDT | HEAVY RAIN 8.91 | Cranbury, NJ | |
| Aug 22, 9:08 AM EDT | HEAVY RAIN 9.44 | Cranbury, NJ | 36 HOUR TOTAL. |
| Aug 22, 9:11 AM EDT | FLOOD | Cranbury, NJ | BRAINERD LAKE IS OVERFLOWING ITS BANKS, MAIN STREET IS CLOSED. 3 FEET OF WATER IN NEARBY RESIDENTS. |
| Aug 22, 9:22 AM EDT | FLASH FLOOD | 1 Se Princeton Junction, NJ | GROVERS MILL POND HAD FLOODED SEVERAL ROADS SURROUNDING. NEIGHBORING BUILDINGS ALSO HAD WATER DAMAGE. TIME BASED ON SOCIAL MEDIA POST. |
| Aug 22, 10:10 AM EDT | HEAVY RAIN 3.92 | Lawrenceville, NJ | |
| Aug 22, 10:27 AM EDT | FLOOD | 1 Wnw Yorketown, NJ | CONMACK LANE, WILSON AVENUE, AND SOBECHO ROAD CLOSED FROM FLOODING. TIME BASED ON DISPATCH REPORTS AND SOCIAL MEDIA POSTS. |
| Aug 22, 10:38 AM EDT | HEAVY RAIN 2.75 | Mercerville, NJ | |
| Aug 22, 11:00 AM EDT | FLOOD | 1 Nne Manalapan Twp, NJ | FLOODING ON ENGLISHTOWN ROAD FORCED ITS CLOSURE NEAR UNION HILL ROAD. TIME BASED ON DISPATCH REPORT. |
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, 9.6 hours before the alert went out and 154 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.
- Mixed-layer CAPE
- 1163 J/kg
- Mixed-layer CIN
- -6 J/kg
- Mixed-layer LCL
- 543 m above ground
- 0-6 km bulk shear
- 21 kt
- 0-1 km storm-relative helicity
- 75 m²/s²
- 0-3 km storm-relative helicity
- 85 m²/s²
- Significant tornado parameter
- 0.3
- Supercell composite
- 1.7
The text
As transmitted.
399
WGUS51 KPHI 220936
FFWPHI
NJC021-023-025-035-221500-
/O.NEW.KPHI.FF.W.0053.210822T0936Z-210822T1500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
536 AM EDT Sun Aug 22 2021
The National Weather Service in Mount Holly has issued a
* Flash Flood Warning for...
Eastern Mercer County in central New Jersey...
Southwestern Monmouth County in central New Jersey...
Southern Middlesex County in northern New Jersey...
South Central Somerset County in northern New Jersey...
* Until 1100 AM EDT.
* At 536 AM EDT, Doppler radar indicated heavy rain across the
warned area. Between 3 and 5 inches of rain have fallen.
Additional rainfall amounts of 1 to 2 inches are possible in the
warned area. Flash flooding is already occurring.
HAZARD...Life threatening flash flooding caused by heavy rain.
SOURCE...Radar.
IMPACT...Life threatening flash flooding of creeks and streams,
urban areas, highways, streets, and underpasses.
* Some locations that will experience flash flooding include...
Old Bridge, East Brunswick, South Brunswick, Manalapan, Princeton,
Jamesburg, Hightstown, Cranbury, Allentown, Roosevelt, Rocky Hill,
and Twin Rivers.
This includes the following highways...
New Jersey Turnpike between exits 8 and 9.
Interstate 295 in New Jersey between mile markers 64 and 69.
Interstate 195 in New Jersey between mile markers 4 and 16.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Motorists should not attempt to drive around barricades or drive
cars through flooded areas.
&&
LAT...LON 4042 7461 4046 7453 4045 7452 4037 7428
4026 7433 4018 7438 4017 7440 4017 7441
4016 7442 4015 7444 4015 7445 4014 7453
4017 7464 4023 7470 4029 7474 4034 7471
4039 7464
FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
Iovino3 follow-up statements
472
WGUS71 KPHI 221014
FFSPHI
Flash Flood Statement
National Weather Service Mount Holly NJ
614 AM EDT Sun Aug 22 2021
NJC021-023-025-035-221500-
/O.CON.KPHI.FF.W.0053.000000T0000Z-210822T1500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Mercer NJ-Middlesex NJ-Monmouth NJ-Somerset NJ-
614 AM EDT Sun Aug 22 2021
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 11 AM EDT THIS
MORNING FOR EASTERN MERCER, SOUTHWESTERN MONMOUTH, SOUTHERN
MIDDLESEX, AND SOUTH CENTRAL SOMERSET COUNTIES...
At 614 AM EDT, Local law enforcement and other sources report
significant flooding in and around Jamesburg, South Brunswick and
Cranbury. Between 4 and 7 inches of rain have fallen. Additional
rainfall amounts of 1 to 2 inches are possible in the warned area.
Flash flooding is already occurring with water rescues occurring.
HAZARD...Life threatening flash flooding caused by heavy rain.
SOURCE...Law enforcement reported.
IMPACT...Life threatening flash flooding of creeks and streams,
urban areas, highways, streets, and underpasses.
Some locations that will experience flash flooding include...
Old Bridge, East Brunswick, South Brunswick, Manalapan, Princeton,
Jamesburg, Hightstown, Cranbury, Allentown, Roosevelt, Rocky Hill,
and Twin Rivers.
This includes the following highways...
New Jersey Turnpike between exits 8 and 9.
Interstate 295 in New Jersey between mile markers 64 and 69.
Interstate 195 in New Jersey between mile markers 4 and 16.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Motorists should not attempt to drive around barricades or drive
cars through flooded areas.
&&
LAT...LON 4042 7461 4046 7453 4045 7452 4037 7428
4026 7433 4018 7438 4017 7440 4017 7441
4016 7442 4015 7444 4015 7445 4014 7453
4017 7464 4023 7470 4029 7474 4034 7471
4039 7464
FLASH FLOOD...OBSERVED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
Iovino035
WGUS71 KPHI 221220
FFSPHI
Flash Flood Statement
National Weather Service Mount Holly NJ
820 AM EDT Sun Aug 22 2021
NJC021-023-025-035-221500-
/O.CON.KPHI.FF.W.0053.000000T0000Z-210822T1500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Mercer NJ-Middlesex NJ-Monmouth NJ-Somerset NJ-
820 AM EDT Sun Aug 22 2021
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 11 AM EDT THIS
MORNING FOR EASTERN MERCER, SOUTHWESTERN MONMOUTH, SOUTHERN
MIDDLESEX, AND SOUTH CENTRAL SOMERSET COUNTIES...
At 820 AM EDT, local law enforcement reported flash flooding in
Jamesburg, South Brunswick, Cranbury, South River, East Windsor,
Hightstown, and vicinity. Numerous water rescues have been reported
in these areas, with many vehicles stranded and some submerged in
water. Some residences have been evacuated in the Cranbury and
Jamesburg areas. This is a dangerous situation. Between 4 and 9
inches of rain have fallen. Additional rainfall amounts of 0.5 to
1.5 inches are possible in the warned area. Flash flooding will
continue through the morning.
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 will experience flash flooding include...
Old Bridge, East Brunswick, South Brunswick, Manalapan, Princeton,
Jamesburg, Hightstown, Cranbury, Allentown, Roosevelt, Rocky Hill,
and Twin Rivers.
This includes the following highways...
New Jersey Turnpike between exits 8 and 9.
Interstate 295 in New Jersey between mile markers 64 and 69.
Interstate 195 in New Jersey between mile markers 4 and 16.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around...don't drown when encountering flooded roads. Most
flood deaths occur in vehicles.
&&
LAT...LON 4042 7461 4046 7453 4045 7452 4037 7428
4026 7433 4018 7438 4017 7440 4017 7441
4016 7442 4015 7444 4015 7445 4014 7453
4017 7464 4023 7470 4029 7474 4034 7471
4039 7464
FLASH FLOOD...OBSERVED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
CMS641
WGUS71 KPHI 221456
FFSPHI
Flash Flood Statement
National Weather Service Mount Holly NJ
1056 AM EDT Sun Aug 22 2021
NJC021-023-025-035-221506-
/O.EXP.KPHI.FF.W.0053.000000T0000Z-210822T1500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Mercer NJ-Middlesex NJ-Monmouth NJ-Somerset NJ-
1056 AM EDT Sun Aug 22 2021
...FLASH FLOOD WARNING WILL EXPIRE AT 11 AM EDT THIS MORNING FOR
EASTERN MERCER, SOUTHWESTERN MONMOUTH, SOUTHERN MIDDLESEX, AND SOUTH
CENTRAL SOMERSET COUNTIES...
The flash flood warning has been replaced by a flood warning. Please
continue to heed road closures.
A Flood Watch remains in effect until 800 AM EDT Monday for portions
of northern Delaware...New Jersey...and Pennsylvania.
LAT...LON 4042 7461 4046 7453 4045 7452 4037 7428
4026 7433 4018 7438 4017 7440 4017 7441
4016 7442 4015 7444 4015 7445 4014 7453
4017 7464 4023 7470 4029 7474 4034 7471
4039 7464
$$
CMSThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 21, 9:35 PM EDT | Areal Flood Advisory | PHI | Mercer, Middlesex, Monmouth, Ocean | 3 hr |
| Aug 21, 10:47 PM EDT | Areal Flood Advisory | PHI | Morris | 3 hr |
| Aug 21, 11:38 PM EDT | Areal Flood Advisory | PHI | Atlantic, Burlington, Monmouth, Ocean | 3 hr |
| Aug 22, 12:04 AM EDT | Areal Flood Advisory | PHI | Atlantic, Burlington, Camden, Monmouth, Ocean | 3 hr |
| Aug 22, 12:24 AM EDT | Flash Flood Warning | PHI | Morris | 3 hr |
| Aug 22, 1:30 AM EDT | Areal Flood Advisory | PHI | Middlesex, Monmouth | 4 hr |
| Aug 22, 1:35 AM EDT | Areal Flood Advisory | PHI | Morris, Somerset | 3 hr |
| Aug 22, 2:04 AM EDT | Flash Flood Warning | PHI | Middlesex, Monmouth | 9 hr |
| Aug 22, 2:09 AM EDT | Flash Flood Warning | PHI | Burlington, Ocean | 5 hr |
| Aug 22, 2:40 AM EDT | Flash Flood Warning | PHI | Hunterdon, Morris, Somerset | 5 hr |
| Aug 22, 3:10 AM EDT | Flash Flood Warning | PHI | Burlington, Hunterdon, Mercer, Monmouth, Ocean | 8 hr |
| Aug 22, 4:21 AM EDT | Flash Flood Warning | PHI | Monmouth, Ocean | 3 hr |
| Aug 22, 6:07 AM EDT | Flash Flood Warning | PHI | Hunterdon, Warren | 67 min |
| Aug 22, 7:52 AM EDT | Areal Flood Warning | PHI | Hunterdon, Somerset | 15 hr |
| Aug 22, 10:43 AM EDT | Special Marine Warning | PHI | 62 min | |
| Aug 22, 10:49 AM EDT | Areal Flood Warning | PHI | Middlesex, Monmouth, Somerset | 13 hr |
| Aug 22, 10:52 AM EDT | Areal Flood Warning | PHI | Hunterdon, Mercer, Monmouth | 13 hr |
| Aug 22, 11:06 AM EDT | Special Marine Warning | PHI | 54 min | |
| Aug 22, 1:35 PM EDT | Coastal Flood Advisory | PHI | Cape May | 10 hr |
| Aug 22, 1:53 PM EDT | Areal Flood Advisory | PHI | Morris | 6 hr |
| Aug 22, 3:21 PM EDT | River Flood Warning | PHI | Somerset | 54 hr |
| Aug 22, 5:07 PM EDT | Areal Flood Advisory | PHI | Morris, Sussex, Warren | 6 hr |
| Aug 22, 5:48 PM EDT | Flash Flood Warning | PHI | Morris, Sussex, Warren | 6 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.