Flash Flooding and Hail in New York, May 29 to 30, 2002

Name: Flash Flooding and Hail in New York, May 29 to 30, 2002
Start: 2002-05-29T12:10
End: 2002-05-30T07:00
Location: New York

May 29 to 30, 2002 · NWS BUF · 6 events in 4 counties and zones

Thunderstorms developed in warm, moist, unstable air during the afternoon and evening hours downing trees and power lines. Up to 5000 homes were without power at the peak of the storm.

Where it happened

Every event with a place to put it; 2 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

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The toll

Deaths: 0
Injuries: 0
Property damage: $1.1 million
Crop damage: None recorded
Events: 6

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 BUF wrote it up.

Thunderstorms developed in warm, moist, unstable air during the afternoon and evening hours downing trees and power lines. Up to 5000 homes were without power at the peak of the storm. Hail up to 1 inch in diameter was reported in Perry, Wyoming county. The training thunderstorms dropped four to six inches of rain in two to three hours in a localized area from Phelps to Newark. A State of Emergency was declared that was declared in Newark remained in effect for a week with most schools and businesses closed during that time. Nearly 300 basements were flooded and several roads covered with up to a foot of water remained closed for several days.

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 Buffalo, NY wrote its last area forecast discussion before the first event at May 29, 9:42 AM EST, 2 hours 28 minutes earlier.

Area forecast discussion, May 29, 9:42 AM EST, 2 hours 28 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BUFFALO NY
1042 AM EDT WED MAY 29 2002

CURRENT FORECAST FOR TODAY LOOKS TO BE IN FAIRLY GOOD SHAPE AT THIS
TIME. WNY IS NOW UNDER THE INFLUENCE OF A TROPICAL AIRMASS (SFC
DEWS IN THE LOW 60S AND PWATS AROUND 1.2 INCHES). THE ATMOSPHERIC
COLUMN IS PROGGED TO MOISTEN EVEN FURTHER AS THE DAY PROGRESSES
(PWATS RISE TO 1.5 BY LATE AFTERNOON PER BUFKIT SOUNDINGS AND MODEL
PROGS)...THIS FACTOR COMBINED WITH DAYTIME HEATING WILL PRODUCE A
VERY JUICY AND UNSTABLE AIRMASS BY EARLY AFTERNOON (CAPES 1500-1600
J/KG). WITH ALMOST NIL CIN...THE INSTABILITY ALONE SHOULD BE ENOUGH
TO AT LEAST FIRE SCATTERED CONVECTION...AND ANY WEAK TRIGGERS WILL
BE ENOUGH TO SET OFF MORE CONCENTRATED ACTIVITY. WE WILL HAVE TWO
SUCH FEATURES TO CONCERN OURSELVES WITH THIS AFTERNOON: (1) A VERY
SUBTLE 500 MB SHORTWAVE CROSSING THE AREA... AND (2) ANY LAKE
BREEZES THAT DEVELOP IN THE WEAK LOW-LEVEL SOUTHERLY FLOW. PER A
GLANCE AT OUR DUNKIRK CMAN SITE AND A PHONE CALL FROM WFO
CLE...WINDS HAVE ALREADY SWITCHED TO NORTHWEST/NORTH AT A FEW
LOCATIONS ALONG THE LAKE ERIE SHORELINE...AND I EXPECT A SIMILAR
SITUATION TO EVOLVE ALONG LAKE ONTARIO THIS AFTERNOON. WITH SUCH
FEATURES PRESENT...I FEEL IT PRUDENT TO CONTINUE WITH LIKELY POPS
FOR THIS AFTERNOON.

GIVEN THE CURRENT OBSERVATIONS AND SATELLITE IMAGERY...PARTLY SUNNY
SKIES AND CURRENT FORECAST TEMPS ALSO LOOK ON TARGET...ABOUT THE
ONLY CHANGE I WILL MAKE IS TO INCLUDE A MENTION OF COOLER NEAR THE
LAKES DUE TO THE WEAK LAKE BREEZE CIRCULATIONS WE EXPECT THIS
AFTERNOON. WILL ALSO MENTION ONSHORE WINDS NEAR THE LAKES AS
WELL...KEEPING THE SOUTHERLY GRADIENT ELSEWHERE.

AS A FINAL NOTE...IVE MADE SOME CHANGES TO CLEAN UP THE WORDING OF
THE EXTENDED PORTIONS OF THE FORECAST...THOUGH FOR NOW IVE OPTED TO
LEAVE THE GENERAL TONE OF THE FORECAST THE SAME FROM PERIOD 2
ONWARD...EVEN THOUGH I HAVE CONSIDERABLE DOUBTS ABOUT THE CURRENT
FORECAST OF RAIN FOR FRIDAY NIGHT GIVEN THE LATEST RUN OF THE AVN.
WILL INSTEAD LEAVE ANY CHANGES TO THE EXTENDED FOR THE AFTERNOON
PACKAGE...AFTER I GET A LOOK AT THE NEXT SET OF MODEL GUIDANCE.

WRKZFP ALREADY GONE...ZONES TO HIT THE HIGHWAY BY 1045.

THANX FOR COORD CLE

.BUF...NONE.

JJR

The radar

The Buffalo radar (KBUF), 89 km away, was scanning. The volume nearest the first event began at 17:07 UTC.

Open the radar archive at this moment

Event by event

3 thunderstorm wind, 2 flash flood, 1 hail. Local standard time, as filed.

Thunderstorm Wind, Monroe

When: May 29, 12:10 PM EST
Where: Monroe County, Rochester Arpt
Measured: 52 kt (60 mph)
Property damage: $25,000
Reported by: AWOS,ASOS,MESONET,ETC
Coordinates: 43.117, -77.667

Hail, Wyoming

When: May 29, 2:25 PM EST
Where: Wyoming County, Perry
Measured: 1 in hail
Property damage: $10,000
Reported by: TRAINED SPOTTER
Coordinates: 42.717, -78.000

Thunderstorm Wind, Wyoming

When: May 29, 2:35 PM EST
Where: Wyoming County, Perry Center
Measured: 50 kt (58 mph)
Property damage: $15,000
Reported by: LAW ENFORCEMENT
Coordinates: 42.750, -78.000

Flash Flood, Ontario

When: May 29, 3:35 PM EST to 10:00 PM EST
Where: Ontario County, Phelps
Property damage: $250,000
Reported by: TRAINED SPOTTER
Coordinates: 42.853, -77.300 (the zone’s center; the record gives no point)

Flash Flood, Wayne

When: May 29, 4:25 PM EST to May 30, 7:00 AM EST
Where: Wayne County, Newark
Property damage: $750,000
Reported by: EMERGENCY MANAGER
Coordinates: 43.066, -76.978 (the zone’s center; the record gives no point)

Thunderstorm Wind, Wayne

When: May 29, 4:25 PM EST
Where: Wayne County, Newark
Measured: 50 kt (58 mph)
Property damage: $15,000
Reported by: TRAINED SPOTTER
Coordinates: 43.050, -77.100

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.
Hail: Hail three-quarters of an inch or larger, or smaller hail that caused damage, filed with the largest stone measured.
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 York in 2002 Every state in 2002 This day in weather history Warnings in New York, May 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: 5298776, 5298779, 5298777, 5298774, 5298775, 5298778.