There are only a few “classic” northeastern U.S. tornado outbreaks that jump out in my mind. The 1985 Pennsylvania outbreak is one, the 1998 Pennsylvania/New York outbreak is another, and so is the 1989 northeast outbreak. The epicenter of that outbreak was right here in Connecticut with an F4 tornado touchdown in Hamden and New Haven.
The atmosphere couldn’t have been more primed for a big tornado event. Here’s the morning weather balloon launch and sounding from Albany.
A classic "elevated mixed layer" is present which is something almost always found in Kansas and Oklahoma before big tornado events. On July 10, 1989 that kind of explosive atmosphere was over Connecticut. What is also striking is the exceptional wind shear in the atmosphere. The wind rapidly strengthens and turns in a clockwise direction with height placing Connecticut in the cross hairs of a big event.
The first tornado touched down in upstate New York west of Albany and was on the ground for an incredible 42 miles. That same supercell went on to produce a series of tornadoes in Connecticut. The first tornado touched down near Route 4 in Cornwall and continued south into Bantam. The second tornado touched down in Watertown and Waterbury. The most violent of the tornadoes touched down in Hamden and continued south into New Haven.
The damage in Connecticut was substantial with hundreds and hundreds of homes and businesses destroyed. Many people in the New Haven suburbs – including North Haven and North Branford were caught in the hail core of the storm with golf ball size hail or larger. Southeast of where the tornado lifted in Newhallville substantial wind damage occurred with many of the pine trees near Lake Saltonstall on the Branford/East Haven line snapped in half.
There were other tornadoes that day – some in northern Massachuetts, others just west of Danbury in Putnam County, and another swarm in northern New Jersey. If we were able to look at radar data (which sadly, we cannot) we’d probably see a string of supercells draped across the region.
On a personal note, the 1989 tornado event is my first weather memory as a kid. At the time I was living in Branford but on vacation with my family on Cape Cod. When I heard about the tornado back home I was devastated! I couldn’t believe that I missed “the big one” back home. I'm not sure if the '89 tornado was what sparked my life-long love of weather but it's clear looking back that it helped solidify my dream of being a meteorologist.