INDIANAPOLIS (WISH) — Thursday’s storm damage may look like it was from a tornado, but it was actually straight-line winds that caused many trees and power lines to fall.
The northeast side of Indianapolis was hit hard Thursday night with wind gusts around 60 mph.
The entrance to an apartment complex near the intersection of Allisonville Road and 91st Street was blocked off for most of the night due to fallen trees, and on Friday afternoon thousands in Marion and Hamilton counties were still without power.
It’s a frequent mistake to think tornadoes are the only weather event that leaves damage of the kind seen Thursday night. Damage caused by straight-line winds is actually more common than tornadoes.
As cold air descends from a thunderstorm, it hits the Earth’s surface and compresses, which helps to increase its speed.
Straight-line winds can sometimes cover a horizontal area as much as 6 miles wide.
One key difference between straight-line and tornado damage is that wind flows out, so downed trees are often lying in straight lines, whereas tornado damage debris is found lying in a circular pattern.
Straight-line winds can reach anywhere from 60-100 mph.
As Thursday night’s storm shows, straight-line winds can cause even more damage than a weak EF0 tornado.