Flash Flooding and Flood in Connecticut, August 17, 1998

Name: Flash Flooding and Flood in Connecticut, August 17, 1998
Start: 1998-08-17T09:15
End: 1998-08-17T10:00
Location: Connecticut

August 17, 1998 · NWS OKX · 3 events in 3 counties and zones

The heaviest rain, which fell in a band from Southeast New Haven County northeast across Central Middlesex County, caused widespread flooding of streets, low-lying, and poor drainage areas. Rain fell at the rate of up to 3 and 1/2 inches per hour across the region.

Where it happened

Every event with a place to put it; 3 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: None recorded
Crop damage: None recorded
Events: 3

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 OKX wrote it up.

As thunderstorms moved over the same area, they produced heavy rain for long periods of time.The heaviest rain, which fell in a band from Southeast New Haven County northeast across Central Middlesex County, caused widespread flooding of streets, low-lying, and poor drainage areas. Rain fell at the rate of up to 3 and 1/2 inches per hour across the region. In New Haven County, the heaviest rainfall was from 3.78 inches at Madison to 4.21 inches in Guilford. A spotter from West Haven measured 3 and 1/2 inches in 1 hour.Heavy rain also occurred across Northwest New London County. Rainfall amounts were from 2.44 inches at Lebanon to 3.31 inches at Bartlett Brook.

The radar

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

Open the radar archive at this moment

Event by event

2 flash flood, 1 flood. Local standard time, as filed.

Flash Flood, New Haven

When: August 17, 9:15 AM EST
Where: New Haven County, Southeast Portion
Reported by: EMERGENCY MANAGER
Coordinates: 41.362, -72.844 (the zone’s center; the record gives no point)

Flash Flood, Middlesex

When: August 17, 9:30 AM EST
Where: Middlesex County, Central Portion
Reported by: EMERGENCY MANAGER
Coordinates: 41.451, -72.508 (the zone’s center; the record gives no point)

Flood, New London

When: August 17, 10:00 AM EST
Where: New London County, Lebanon
Reported by: TRAINED SPOTTER
Coordinates: 41.504, -72.101 (the zone’s center; the record gives no point)

What these are

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.

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

The same day elsewhere

Every storm in Connecticut in 1998 Every state in 1998 This day in weather history Warnings in Connecticut, August 1998

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: 5660645, 5660646, 5660647.