Wow, I drive by them all the time out in West Texas and they sure don’t seem to be turning at anywhere near that speed...
Were they turning at the time?
There’s a wind farm about 30 miles away from me in Waymart PA. I’ve seen the rotors turning at a decent speed; not hard to conceive of the tips of the rotors exceeding 100 mph. Remember that the outer edge of a rotor blade spins faster than the edges closer to the center.