Flash Flooding and Flooding in New Jersey, March 29 to 31, 2001

Name: Flash Flooding and Flooding in New Jersey, March 29 to 31, 2001
Start: 2001-03-29T13:00
End: 2001-03-31T23:59
Location: New Jersey

March 29 to 31, 2001 · NWS PHI · 13 events in 13 counties and zones

Heavy rain fell across most of New Jersey on the 29th and 30th. The rain caused urban and poor drainage flooding as well as flooding across a few of the rivers, streams and creeks in the state.

Where it happened

Every event with a place to put it; 13 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.

Tornadoes
Tropical storms and surge
Floods
Wind
Hail
Winter weather
Heat and drought
Cold
Fire, smoke and dust
Marine and coastal
Other

Open the live radar over this ground

The toll

Deaths: 0
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 13

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What happened

The episode as NWS PHI wrote it up.

Heavy rain fell across most of New Jersey on the 29th and 30th. The rain caused urban and poor drainage flooding as well as flooding across a few of the rivers, streams and creeks in the state. Light rain spread from south to north during the afternoon of the 29th and fell heavy at times during the late evening of the 29th and the morning of the 30th. The rain ended (again from the south to north) during the late morning and afternoon of the 30th. Storm totals averaged between 1.5 and 2.5 inches. Monmouth County was one of the hardest hit counties. A senior citizen facility in Ocean Township was threatened by flooding along the Poplar Brook. Access to another senior citizen facility in Tinton Falls was blocked by four feet of standing water for several hours. Serious road flooding was also reported in the bayshore communities along New Jersey State Routes 35 and 36 as well as in Neptune, Manalapan and Oceanport. Flooding forced road closures in Holmdel Township. In Squankum, the Manasquan River was above its estimated flood stage of 7 feet from 1126 a.m. EST on the 30th through 4 a.m. EST on the 31st. It crested at 8.28 feet at 945 p.m. EST on the 30th.In Somerset County, flooding along the Millstone River caused the closure of the Blackwells Mills and Griggstown Causeways. One road over the North Branch of the Raritan River was also closed between Branchburg and Bridgewater Townships. The Millstone River at Griggstown reached its 9 foot flood stage at 1040 a.m. EST on the 30th. It crested at 11.7 feet at 9 p.m. EST on the 30th, but took until 9 a.m. EST on April 1st to get back below flood stage. Farther downstream, the Millstone River at Blackwells Mills reached its 9 foot flood stage at Midnight EST on the 31st, crested at 9.7 feet at 230 a.m. EST and was back within bankfull at 137 p.m. EST on the 31st. In Camden County, the Cooper River flooded and sent its waters into the backyards of several homes in Cherry Hill. At Haddonfield, the Cooper River reached its 2.8 foot flood stage at 659 a.m. EST on the 30th, crested at 3.22 feet at 845 a.m. EST and was back within bankfull at 435 p.m. EST on the 30th. In Mercer County, the Assunpink Creek was above its 7 foot flood stage from 550 a.m. EST through 853 p.m. EST on the 30th. It crested at 9.17 feet at 1250 p.m. EST.Specific storm totals included 3.00 inches in New Monmouth (Monmouth County), 2.95 inches in Willingboro (Burlington County), 2.80 inches in Mount Ephraim (Camden County), 2.72 inches in Cherry Hill (Camden County), 2.60 inches in Trenton (Mercer County), 2.53 inches in Hightstown (Mercer County) and Somerdale (Camden County), 2.52 inches in Mount Laurel (Burlington County), 2.50 inches in Eatontown (Monmouth County), 2.47 inches in New Brunswick (Middlesex County) and Marlboro (Monmouth County), 2.46 inches in Verga (Gloucester County), 2.45 inches in Reigelsville (Hunterdon County), 2.43 inches in Sewell (Gloucester County), 2.36 inches in West Deptford (Gloucester County), 2.31 inches in Mount Holly (Burlington County), 2.24 inches in Keansburg (Monmouth County), 2.15 inches in Point Pleasant (Ocean County), 2.14 inches in Belle Mead (Somerset County), 2.10 inches in Bound Brook (Somerset County), 2.00 inches in Chatham (Morris County), 1.96 inches in Blackwells Mills (Somerset County), 1.93 inches in Flemington (Hunterdon County) and Freehold (Monmouth County), 1.89 inches in Morristown (Morris County), 1.88 inches in Washington's Crossing (Mercer County), 1.85 inches in Wertsville (Hunterdon County), 1.83 inches in Estelle Manor (Atlantic County) and 1.79 inches in Seabrook (Cumberland County) A low pressure system developed over the Gulf of Mexico the night of the 28th. By the morning of the 29th, it moved northeast into the Florida Panhandle and by the morning of the 30th, it reached the Delmarva Peninsula. The low moved offshore that morning and by the morning of the 31st was located near Nova Scotia.

What forecasters said that day

The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Philadelphia/Mount Holly wrote its last area forecast discussion before the first event at Mar 29, 10:35 AM EST, 2 hours 25 minutes earlier.

Area forecast discussion, Mar 29, 10:35 AM EST, 2 hours 25 minutes before

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1035 AM EST THU MAR 29 2001

WL ISSUE FLD WATCH AT THIS TIME FOR MUCH OF CWA FOR TNGT AND FRI...
AS ENUF OF 12Z RUN HAS COME IN TO CAUSE US SOME CONCERN RE FLDG.
ONLY AREAS LEFT OUT OF FLD WATCH ARE SRN/CNTRL DE AND MOST OF NERN
MD SHORE. WITH MODEL QPF AMTS BTWN 1 AND 2 INCHES...AND CLOSE TO 2
INCHES EVEN ON NEW ETA FOUS...RFC PROJECTIONS ARE FOR AT LEAST MINOR
FLDG IN PARTS OF PASSAIC/RARITAN BASINS. NGM SHOWS CORE OVER
CNTRL/SRN NJ BY 12Z FRI.

COORD WITH ALL SURROUNDING OFFICES.

SOME OTHER MINOR CHGS TO WIND DIR AND AFTN MAXES...OTHERWISE REST AS
FROM PREVIOUS...

*********************************************************************

LIGHT RAIN WAS UP AS FAR AS RALEIGH AND GREENSBORO AT 200 AM.  IT
LOOKS AS THOUGH THE LEADING EDGE OF THE RAIN WILL BE UP ABOUT AS FAR
AS KUTZTOWN...TRENTON AND SEASIDE HEIGHTS BY ABOUT 100 PM.  TODAY/S
RAIN WILL BE LIGHT FOR THE MOST PART...WITH PERHAPS UP TO A QUARTER
INCH BY EVENING IN SOUTHERN DELAWARE.  IN THE NORTH...IT CONTINUES
TO APPEAR AS THOUGH THE LOWEST LEVEL OF THE ATMOSPHERE WILL BE TOO
WARM TO SUPPORT ANY FROZEN PRECIP...ESPECIALLY WITH THE PRECIP RATES
BEING RELATIVELY LIGHT.

THE SHORT WAVE TROUGH PRESENTLY OVER THE WESTERN GULF OF MEXICO IS
FORECAST TO SWING TO THE NORTHEAST...PASSING OVER OUR REGION EARLY
ON FRIDAY.  THE HEAVIEST PRECIP WILL BE OUT AHEAD OF THAT FEATURE...
AFFECTING US TONIGHT INTO PERHAPS FRIDAY MORNING.  WE/LL SHAVE A
LITTLE OFF OF THE GUIDANCE PRECIP VALUES (IN GENERAL) BEING THAT
THEY SEEM TO BE RUNNING A LITTLE HIGH OF LATE (ALSO A
GENERALIZATION).  WE/LL PLAN ON PRECIP TOTALS (NOON TODAY THROUGH
NOON FRIDAY) OF 3/4 TO 1 INCH AROUND PHL...PERHAPS 1 TO 1 1/4 INCHES
IN SOUTHERN DELAWARE AND EXTREME SOUTHERN NEW JERSEY...AND MAYBE 1/2
INCH UP IN THE POCONOS.  WE WILL NOT ISSUE A FLOOD WATCH AT THIS
TIME SINCE THE HEAVIEST PRECIP SHOULD FALL OVER OUR LESS FLOOD PRONE
COUNTIES.

AFTER THE HEAVY RAIN MOVES OUT OF THE REGION ON FRIDAY MORNING...IT
LOOKS LIKE WE/LL BE LEFT WITH A CHILLY NORTHERLY FLOW ALONG WITH
CLOUDS...OCCASIONAL RAIN AND DRIZZLE FOR THE BALANCE OF FRIDAY.

THE ZONE FORECASTS WILL BE ISSUED AROUND 415.

.PHI...FLOOD WATCH TONIGHT AND FRI FOR PAZ054-055-060>062-067>071-
       NJZ001-007>010-012>026-DEZ001-MDZ008-310000-.
       SMALL CRAFT ADVISORY FROM SANDY HOOK NJ TO FENWICK ISLAND DE
       AND FOR LOWER BAY.

IOVINO /

The radar

The national radar mosaic for the moment the first event began.

Open the radar archive at this moment

Event by event

9 heavy rain, 2 flood, 2 flash flood. Local standard time, as filed.

Heavy Rain, Cumberland

When: March 29, 1:00 PM EST to March 30, 10:00 AM EST
Where: Cumberland County, Countywide
Reported by: AWOS,ASOS,MESONET,ETC
Coordinates: 39.328, -75.129 (the zone’s center; the record gives no point)

Heavy Rain, Salem

When: March 29, 1:00 PM EST to March 30, 11:00 AM EST
Where: Salem County, Countywide
Reported by: AWOS,ASOS,MESONET,ETC
Coordinates: 39.577, -75.358 (the zone’s center; the record gives no point)

Heavy Rain, Atlantic

When: March 29, 2:00 PM EST to March 30, 12:00 PM EST
Where: Atlantic County, Countywide
Reported by: AWOS,ASOS,MESONET,ETC
Coordinates: 39.469, -74.634 (the zone’s center; the record gives no point)

Heavy Rain, Gloucester

When: March 29, 2:00 PM EST to March 30, 1:00 PM EST
Where: Gloucester County, Countywide
Reported by: AWOS,ASOS,MESONET,ETC
Coordinates: 39.717, -75.142 (the zone’s center; the record gives no point)

Heavy Rain, Ocean

When: March 29, 2:00 PM EST to March 30, 2:00 PM EST
Where: Ocean County, Countywide
Reported by: AWOS,ASOS,MESONET,ETC
Coordinates: 39.866, -74.250 (the zone’s center; the record gives no point)

Heavy Rain, Burlington

When: March 29, 2:30 PM EST to March 30, 1:30 PM EST
Where: Burlington County, Countywide
Reported by: AWOS,ASOS,MESONET,ETC
Coordinates: 39.878, -74.668 (the zone’s center; the record gives no point)

Heavy Rain, Hunterdon

When: March 29, 5:00 PM EST to March 30, 4:00 PM EST
Where: Hunterdon County, Countywide
Reported by: AWOS,ASOS,MESONET,ETC
Coordinates: 40.567, -74.912 (the zone’s center; the record gives no point)

Heavy Rain, Middlesex

When: March 29, 5:00 PM EST to March 30, 4:00 PM EST
Where: Middlesex County, Countywide
Reported by: AWOS,ASOS,MESONET,ETC
Coordinates: 40.440, -74.409 (the zone’s center; the record gives no point)

Heavy Rain, Morris

When: March 29, 5:00 PM EST to March 30, 4:00 PM EST
Where: Morris County, Countywide
Reported by: AWOS,ASOS,MESONET,ETC
Coordinates: 40.862, -74.544 (the zone’s center; the record gives no point)

Flood, Mercer

When: March 30, 5:50 AM EST to 9:00 PM EST
Where: Mercer forecast zone
Reported by: AWOS,ASOS,MESONET,ETC
Coordinates: 40.283, -74.702 (the zone’s center; the record gives no point)

Flash Flood, Camden

When: March 30, 6:59 AM EST to 4:35 PM EST
Where: Camden County, Countywide
Reported by: AWOS,ASOS,MESONET,ETC
Coordinates: 39.804, -74.960 (the zone’s center; the record gives no point)

Flood, Somerset

When: March 30, 9:45 AM EST to March 31, 11:59 PM EST
Where: Somerset forecast zone
Reported by: AWOS,ASOS,MESONET,ETC
Coordinates: 40.564, -74.616 (the zone’s center; the record gives no point)

Flash Flood, Monmouth

When: March 30, 10:00 AM EST to March 31, 4:00 AM EST
Where: Monmouth County, Countywide
Reported by: EMERGENCY MANAGER
Coordinates: 40.288, -74.158 (the zone’s center; the record gives no point)

What these are

Heavy Rain: Rainfall totals unusual for the place and season that did not produce a flood.
Flood: Flooding that develops more slowly than a flash flood: rivers leaving their banks, or water standing over land for an extended time.
Flash Flood: Flooding that begins within six hours of the rain that causes it, or of a dam or levee failure or ice jam release, often with deadly speed.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in New Jersey in 2001 Every state in 2001 This day in weather history Warnings in New Jersey, March 2001

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 5235440, 5235445, 5235438, 5235441, 5235444, 5235439, 5235442, 5235443, 5235446, 5235324, 5235322, 5235437, 5235323.