Weather Service investigating 2, maybe 3 other, tornado touch downs from Wednesday storms

National Weather Service investigators are trying to determine the strength of two tornadoes that touched down in Butler County during Wednesday’s storms and are looking into the possibility that two more twisters touched down in the region.

NWS meteorologist Liana Lupo talked about one discovered near Center Township’s Unionville neighborhood.

“We were able to determine it was a tornado (in Butler County) by way of a video we received,” Lupo said. “We could tell by the way the roof came off the building.”

While the storms caused minimal flooding — Lupo said NWS received a few reports of flooded roads near Pittsburgh, along with localized reports of flooding in Lawrence County — they were accompanied by heavy winds and multiple tornado warnings across Southwestern Pennsylvania.

The National Weather Service on Thursday afternoon confirmed via social media there was a second tornado in Butler County. That one occurred along Mack Road in West Sunbury.

Two Butler County tornadoes touched down between 4 and 5 p.m. A local fire department captured video of the storm tossing around the roof of a structure.

“One of the possible additional tornadoes was at the tip of southern Allegheny County, where we issued a warning between 5 and 5:30 p.m.,” Lupo said. “And a possible third was in Washington County, near Canonsburg and heading east.”

Chartiers Township firefighters just outside Canonsburg reported a host of trees and wires down in a confined area bounded by Silver Maples and Green streets, and Walnut Street and Locust Avenue.

Fire officials said a few homes and vehicles were damaged, but no injuries were reported.

Most of the region received about an inch of rain during the storms. Parts of southern Allegheny County received closer to 2 inches.

Lupo said NWS investigators look at a variety of factors to confirm tornadoes and determine their strength.

“For a building, we look at: How strong was the roof? How was it secured to the building?” she said. “If a tree falls, we’re looking at how it fell and what direction. In a straight-line storm, downed trees usually all fall the same direction. In a tornado, you see trees falling on top of one another.”

Investigators also look at what types of trees are damaged, whether they are soft wood like pines and cedars, or hardwood trees like oak, maple and hickory.

“That helps us determine how strong the winds were when a tree was uprooted or snapped,” she said.