Western Pennsylvania has already seen a dozen tornadoes this year, which is double the yearly average, meteorologists say.
Seven of those have been confirmed in May alone, according to Shannon Hefferan, meteorologist at the National Weather Service in Moon Township.
The last time Western Pennsylvania experienced such a large onslaught of twisters came in May 1985. There were 11 that month.
On Saturday, three tornadoes were confirmed: in Finleyville in Washington County, the New Salem area in Fayette County and Fike Run in Fayette County, according to the National Weather Service tweet thread on the social media platform X.
All the surveys are done. Here is the information from the Finleyville tornado that touched down last Saturday in Washington county PA. pic.twitter.com/lAUxHLBwFo
— NWS Pittsburgh (@NWSPittsburgh) May 13, 2024
The twisters in Fayette County were from the same circulation, Hefferan said. She said debris could be seen up to 3,000 feet in the air on the radar Saturday.
“It’s been an active season definitely,” Hefferan said. “And we’re not even in the peak season.”
June is the more active period for tornadoes, according to Hefferan. The National Weather Service in the region’s office coverage area includes Western Pennsylvania, Eastern Ohio and Northern West Virginia.
This week is looking quiet, though, Hefferan said, as there’s no severe weather potential as of now.
The weather has been warm, and there’s been moisture, which can lead to tornadoes, she said.
Ashley Dougherty, a meteorologist at WTAE, said it’s rare to have such an early start to tornado season.
“But with such a mild winter and warming up much earlier, it’s not too shocking,” she said. “Basically, the severe weather season started a month early, so it’s kind of a wait-and-see (period) to see what our June will be like.”
Dougherty also credited La Niña, a climate pattern in the Pacific Ocean that affects weather worldwide, which can be a sign of more severe weather.
However, other conditions have to be present as well, Hefferan said, such as moisture at the surface, cold air aloft, directional winds, high vertical winds, a destabilizing atmosphere and other factors.
“High vertical winds help fuel rotating thunderstorms,” Hefferan said.
On Saturday when the three tornadoes occurred, she said there was a “lower probability” of them happening.
“We try our best to forecast, but we use the warnings to get the notice out,” Hefferan said. “Right now, it’s more active season — everybody just needs to be more aware of what’s going on in the weather.”
Tornadoes can happen in any state, including Pennsylvania, even thought it’s not a tornado hotbed, she said.
“Tornado Alley is an area of the U.S. where there is a high potential for tornado development,” AccuWeather Senior Meteorologist Dan Kottlowski said. “This area encompasses much of northern Texas northward through Oklahoma, Kansas, Missouri and parts of Louisiana, Iowa, Nebraska and eastern Colorado.”
When storms become severe, Hefferan suggested checking social media, TV and alerts, as well as knowing safe spots to take shelter in the event of a tornado.
“If you’re in the path of it, you want to take shelter immediately,” Hefferan said.
Megan Swift is a TribLive reporter covering trending news in Western Pennsylvania. A Murrysville native, she joined the Trib full time in 2023 after serving as editor-in-chief of The Daily Collegian at Penn State. She previously worked as a Jim Borden Scholarship intern at the Trib for three summers. She can be reached at mswift@triblive.com.