The 1989 Northeastern United States tornado outbreak was a series of tornadoes which caused more than $130 million (1989 USD) in damage across the Northeastern United States on July 10, 1989. The storm system affected five states with severe weather, including hail up to 2 1⁄2 inches (6.4 cm) across, thunderstorm winds up to 90 mph (140 km/h; 78 kn), and 17 tornadoes. Several towns in New York and Connecticut were particularly hard-hit. Several homes were leveled in Greenville, New York and extensive damage occurred in Bantam, Connecticut. A large section of Hamden, Connecticut, including an industrial park and hundreds of homes, was completely destroyed; in some places buildings were flattened to the ground.
More than 150 people were injured by the tornado outbreak, and one person was killed by thunderstorm winds. While tornado outbreaks in this area are unusual, this storm was especially rare in that it produced six significant tornadoes, two of which were violent F4s, and featured many tornadoes with tracks of several miles.