An anomaly was detected yesterday on Doppler Radar in Montana by a self-proclaimed weather geek and certified NWS Skywarn spotter when a small area of orange and red echoes made an appearance southwest of Billings in calm weather conditions.
The observer tweeted about it and The National Weather Service responded:
The National Weather Service Billings believes curious turbulence during an otherwise still day was determined likely associated with chairlifts at the Red Lodge Mountain ski area. Pretty cool!