Long Island's first tornado since 2022 hit Thursday. Why did it form and are more expected in future storms?

An EF1 tornado that formed over the ocean made landfall Thursday evening in Atlantic Beach. Within minutes, the twister tossed wood, plaster, beach chairs, toys and personal belongings from 50 cabanas at the Sun & Surf Beach Club and injured one person.

The EF1 is the second weakest of the six classifications on the Enhanced Fujita Scale, meaning it has winds between 86 mph and 110 mph. But a tornado of any magnitude is a rare occurrence on Long Island. Are more expected here in future storms? 

Here's what experts say.

How common are tornadoes on Long Island?

Thursday’s tornado marked the first on Long Island since Sept. 25, 2022, when a tornado classified as EF0, the weakest with winds between 65 mph to 85 mph, spun through Laurel, uprooting trees and ripping up roofs, according to the National Weather Service. The last one in Nassau occurred during a storm on Nov. 13, 2021, when multiple low-level tornadoes were recorded across the Island.

"For our area, it is not common to have a tornado," Nelson Vaz, warning coordination meteorologist for the National Weather Service said during a Friday morning news conference regarding the previous night’s storm. "Maybe once every few years ... we will see a tornado in our area."

Why are tornadoes rare here?

Some parts of the country — most notably "Tornado Alley" in the central United States — have the atmospheric conditions required to form a tornado. One key condition these cyclones require is "a clashing of contrasting air masses," according to Jase Bernhardt, associate professor, director of sustainability studies in the Department of Geology, Environment and Sustainability at Hofstra University. This means dry air, like that coming from the arid Western states, battling moist air, like that which blows north from the Gulf of Mexico. That’s what causes many cyclones in the Great Plains.

Here on Long Island, "we don’t get very dry air masses," Bernhardt said.

"We just don’t have the ingredients that are necessary," he added. "The water around the island tends to moderate the climate a bit."

So why did one form in Thursday night's storm?

The moist air coming off the ocean waters clashed with a "super strong low pressure" unusual for this time of the year that came from the north and west, which tends to be drier, Bernhardt said. Another crucial element for tornadoes was present: vertical wind shear, or a difference in the velocity and direction of the wind at different heights in the atmosphere.

"We did have a notable air mass contrast here," he said. "Also, you had spin generated by the fact that the wind speed and direction was a little bit different over the water versus over the land."

Are tornadoes expected to become more common on Long Island?

If they are, it would take several decades for a measurable trend, and even then, Long Islanders would hardly notice, according to Bernhardt.

Tornado Alley has been shifting east toward parts of Ohio and even Pennsylvania in recent years, which "seems related to" human-caused climate change, Bernhardt said. However, "we’re so far on the fringe" of the shift that it should not impact the Island.

"We could have a slight increase of tornadoes here, but we just have so few that it’s not going to be very noticeable," Bernhardt said. “And even if we do get an increase, they are generally just weak tornadoes that have minimal impact. Of all the things climate change could bring us, it’s not a big thing to focus on. Tornadoes are scary, they can cause damage, but flash flooding is a bigger impact of climate change."