The South Dakota Mesonet station in Sioux Falls measured 70 mph wind gusts at 11:30 p.m. on the night of September 10, about the time the EF2 tornado struck.
“The wind speed measured by the Mesonet is the highest known wind speed measured in the Sioux Falls area throughout the duration of the storm,” said South Dakota Mesonet Director Nathan Edwards.
A damage survey by the National Weather Service estimated winds of up to 125 mph were possible where the tornado touched down about two miles away.
The winds were accompanied by heavy rainfall of up to 1.15 inches per hour at the Sioux Falls station. More than double the amount of rainfall in the Sioux Falls area was recorded at surrounding South Dakota Mesonet stations.
The South Dakota Mesonet is a state-wide network of 26 stations operated by South Dakota State University for agriculture, public safety, research and the public.
For current weather updates, visit mesonet.sdstate.edu.