Surprise! Tornadoes form from the ground up
By Katherine KorneiDec. 13, 2018 , 6:00 PM
Call Dorothy—the formation of tornadoes has been knocked on its head. New measurements from tornadoes in Oklahoma and Kansas suggest these storms’ swirling winds first develop near the ground. That’s contrary to the long-accepted theory that tornado winds are born several kilometers up in clouds and only later touch down on Earth’s surface.
Researchers analyzed four tornadoes, including a monster known as El Reno (shown above), which holds the record as the widest tornado ever measured, at 4.2 kilometers. They noticed something odd when they compared radar measurements that tracked wind speed with hundreds of photographs and videos of El Reno taken by storm chasers: The storm’s funnel was already on the ground several minutes before the radar data—taken roughly 250 meters off the ground—recorded any rotation.
https://www.sciencemag.org/news/2018/12/surprise-tornadoes-form-ground
