Flash Flooding and Flood in New York, August 16, 2002

Name: Flash Flooding and Flood in New York, August 16, 2002
Start: 2002-08-16T13:45
End: 2002-08-16T16:07
Location: New York

August 16, 2002 · NWS OKX · 13 events in 7 counties and zones

7 thunderstorm wind, 4 flash flood, 1 flood, 1 hail, as filed by the National Weather Service.

Where it happened

Every event with a place to put it; 5 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 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 New York, NY wrote its last area forecast discussion before the first event at Aug 16, 9:19 AM EST, 4 hours 26 minutes earlier.

Area forecast discussion, Aug 16, 9:19 AM EST, 4 hours 26 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
1019 AM EDT FRI AUG 16 2002

WEAK WAVES MOVG THRU THE AREA THIS AFTN AND DAYTIME HEATING WITH
CONVECTIVE TMPS REACHED COULD TRIGGER A FEW TSTMS. CAPES GENERALLY
BELOW 1000. WBZ ARND 12K AND MOIST ATMOSPHERE WL PRECLUDE ANY SVR
WX. WITH SLOW MOVG STORMS AND PRECIPITABLE WATERS NR 2 INCHES COULD
SEE HVY RAINS WITH THE STORMS.

***PREVIOUS DISCUSSION***

SHORT RANGE WX DISC...WELL START THE DAY WITH CLOUDY SKIES AND HIGH
HUMIDITY. AS OF 06Z...BKN STRATUS CLOUDS COVER LONG ISLAND AND
SOUTHERN CT AS A PATCH OF MID LVL CLOUDS ADVECT NEWD ACROSS THE
REGION.

FOR TODAY...THE FCST CHALLENGES INCLUDE THE...

POTENTIAL FOR A HEAT ADVISORY...BKN MID AND UPPER LVL CLOUDS ALONG
WITH THE DEVELOPMENT OF LOW LVL CLOUDS WILL SIGNIFICANTLY FILTER THE
SUNSHINE...LIMITING HEATING AND PRODUCING AFTERNOON TEMPS A DEGREE
OR TWO LOWER THAN YESTERDAY AFTERNOON...WHEN THE HEAT INDEX PEAKED
AT 99 DEGS FOR 1 HOUR AT CENTRAL PARK. I WILL MOST CLOSELY FOLLOW
THE ETA MOS GUIDANCE VALUES FOR TEMPS AND DEW PT TEMPS...WHICH WILL
PRODUCE HEAT INDICES IN THE UPPER 90S IN URBAN NE NJ AND THE MID 90S
IN NYC. THUS...LIKE YESTERDAY...WE WILL NOT ISSUE A HEAT ADVISORY
FOR NYC.

POTENTIAL FOR A SMALL CRAFT ADVISORY...UNLIKE YESTERDAY...ALTHOUGH
IM EXPECTING SEA BREEZES TO DEVELOP BETWEEN 15 AND 18Z...THE
SYNOPTIC SCALE GRADIENT WILL BE RELAXING. THE WIND SPEEDS SHOULD
REMAIN AROUND 20 KNOTS WITH SEAS AROUND 4 FT OVERALL. HOWEVER...I
WOULDNT BE SURPRISED IF THE AMBROSE LIGHT TOWER BUOY REPORTED A 25
KNOT WIND FOR AN HOUR OR TWO. AT THIS TIME...ILL HOLD OFF ON
ISSUING ANY SMALL CRAFT ADVISORY FOR THE ATLANTIC COASTAL WATERS
SOUTH OF LONG ISLAND.

POTENTIAL FOR TSTMS...THE MAIN TRIGGERING MECHANISMS WILL BE THE
UPSTREAM WEAK UPPER LVL SHORT WV MVG SEWD TOWARD THE REGION AND THE
DEVELOPMENT OF SEA BREEZES. WITH LOW LVL MOISTURE IN PLACE AND
INCREASING INSTABILITY...IM EXPECTING SCT AFTERNOON TSTMS
DEVELOPING INITIALLY ALONG THESE BOUNDARIES THEN SLOWING ADVECTING
EWD AROUND 10 KTS. WITH PW CONTENTS BETWEEN 1.5 AND 2.0
INCHES...TSTMS WILL HAVE THE POTENTIAL FOR PRODUCING HVY RAINFALL
AND LOCALIZED URBAN FLOODING. ILL BE FORECASTING A 40 PCT POP
INLAND AND 30 PCT ALONG THE COAST...WHICH WILL BE CARRIED INTO THIS
EVENING.

REMAINDER OF THE FORECAST...A SERIES OF WEAK UPPER LVL SHORT WVS AND
LOW LVL TROUGHS WILL MV ACROSS THE REGION THROUGH SAT...FOLLOWED BY
A STRONGER COLD FRONT LATE SUN...WHICH COULD PRODUCE SEVERE WEATHER
ALONG A PRE-FRONTAL SQUALL LINE FOLLOWED BY A FRESH NEW AIR MASS TO
START THE WEEK.

CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...NONE.

GC

The radar

The Brookhaven radar (KOKX), 87 km away, was scanning. The volume nearest the first event began at 18:44 UTC.

Open the radar archive at this moment

Event by event

7 thunderstorm wind, 4 flash flood, 1 flood, 1 hail. Local standard time, as filed.

Thunderstorm Wind, Bronx

When: August 16, 1:45 PM EST
Where: Bronx County, Bronx
Measured: 60 kt (69 mph)
Reported by: EMERGENCY MANAGER
Coordinates: 40.833, -73.900

New York City Office of Emergency Management reported a building collapse.

Thunderstorm Wind, Orange

When: August 16, 2:15 PM EST
Where: Orange County, Scotchtown
Measured: 50 kt (58 mph)
Reported by: TRAINED SPOTTER
Coordinates: 41.483, -74.367

A spotter reported that several trees had been knocked down by the storm.

Thunderstorm Wind, Bronx

When: August 16, 2:30 PM EST
Where: Bronx County, Countywide
Measured: 50 kt (58 mph)
Reported by: EMERGENCY MANAGER
Coordinates: 40.850, -73.867

New York City Office of Emergency Management reported that numerous trees and power lines were knocked down by this storm.

Flash Flood, Bronx

When: August 16, 2:39 PM EST
Where: Bronx County, West Portion
Reported by: EMERGENCY MANAGER
Coordinates: 40.827, -73.924 (the zone’s center; the record gives no point)

New York City Office of Emergency Management reported flooding that shut down the Major Deegan Expressway near West Tremont. NYCOEM and local media reported that there was three feet of water on the Major Deegan Expressway at the Cross Bronx Expressway interchange which required police rescues.

Flash Flood, New York

When: August 16, 2:39 PM EST
Where: New York County, Northwest Portion
Reported by: EMERGENCY MANAGER
Coordinates: 40.774, -73.970 (the zone’s center; the record gives no point)

New York City Office of Emergency Management reported flooding which required in a shutdown of the Henry Hudson Parkway from 96th street to 125th street.

Thunderstorm Wind, Queens

When: August 16, 2:55 PM EST
Where: Queens County, Little Neck
Measured: 50 kt (58 mph)
Reported by: TRAINED SPOTTER
Coordinates: 40.767, -73.750

A spotter reported that severe thunderstorm winds downed trees.

Thunderstorm Wind, Nassau

When: August 16, 2:55 PM EST to 3:01 PM EST
Where: Nassau County, Lake Succes
Measured: 50 kt (58 mph)
Reported by: TRAINED SPOTTER
Coordinates: 40.750, -73.717

Spotters reported downed trees at both Lake Success and New Hyde Park.

Flood, Rockland

When: August 16, 2:55 PM EST to 3:13 PM EST
Where: Rockland County, Stony Pt
Reported by: TRAINED SPOTTER
Coordinates: 41.152, -74.024 (the zone’s center; the record gives no point)

Torrential rain caused urban flooding. Spotters reported flooding on the north bound Palisades Interstate Parkway in the vicinity of Exit 14 in Stony Point at 3:55 pm and street flooding in the hamlets of West Nyack and Blauvelt at 4:13 pm.

Thunderstorm Wind, Westchester

When: August 16, 3:35 PM EST
Where: Westchester County, Mt Vernon
Measured: 50 kt (58 mph)
Reported by: TRAINED SPOTTER
Coordinates: 40.917, -73.850

Spotters reported downed trees.

Thunderstorm Wind, Queens

When: August 16, 3:45 PM EST
Where: Queens County, Queens Vlg
Measured: 50 kt (58 mph)
Reported by: TRAINED SPOTTER
Coordinates: 40.717, -73.750

Spotters reported that high winds produced by severe thunderstorms downed several trees.

Flash Flood, Nassau

When: August 16, 3:55 PM EST
Where: Nassau County, Valley Stream
Reported by: TRAINED SPOTTER
Coordinates: 40.732, -73.585 (the zone’s center; the record gives no point)

Torrential rain caused significant urban flooding from Valley Stream to Rockville Center. In Valley Stream, water ponded up to 2 1/2 feet deep in low lying areas.

Hail, Nassau

When: August 16, 3:57 PM EST to 4:07 PM EST
Where: Nassau County, New Hyde Park
Measured: 0.88 in hail
Reported by: TRAINED SPOTTER
Coordinates: 40.733, -73.633

Spotters observed 0.88-inch diameter (nickel size) hail in New Hyde Park and 3/4-inch diameter hail at Baldwin.

Flash Flood, Queens

When: August 16, 4:05 PM EST
Where: Queens County, Far Rockaway
Reported by: TRAINED SPOTTER
Coordinates: 40.658, -73.839 (the zone’s center; the record gives no point)

Torrential rain produced significant urban flooding in Far Rockaway.

What these are

Thunderstorm Wind: Winds from a thunderstorm of 50 knots (58 mph) or more, or lower winds that caused damage or casualties. Measured gusts are marked MG, estimated EG.
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.
Flood: Flooding that develops more slowly than a flash flood: rivers leaving their banks, or water standing over land for an extended time.
Hail: Hail three-quarters of an inch or larger, or smaller hail that caused damage, filed with the largest stone measured.

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

The same day elsewhere

Every storm in New York in 2002 Every state in 2002 This day in weather history Warnings in New York, August 2002

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: 5313082, 5313083, 5313084, 5313085, 5313086, 5313087, 5313088, 5313094, 5313089, 5313090, 5313091, 5313092, 5313093.