s it possible for windmills to generate a localized rain or thunderstorm?
I notice that on my radar app there is almost always an isolated high-intensity storm hovering over the I-65 between Monticello and Lafayette, Ind. This area has a large wind farm. Is it possible the windmills could generate a localized rain or thunderstorm?
— Scott Harmon, Valparaiso, Ind.
There is no rainstorm, but it is the wind farm itself that is causing the false radar echo to appear. According to the National Weather Service, wind farms can impact Doppler radar in several ways. The wind turbines can block some of the radar beam and reflect it back to the radar, creating a false clutter return. The air motions created by wind farms can also impact the velocity and spectrum width data. The wind farm in the DeKalb area causes the same effect on the Chicago Doppler radar located in Romeoville, with persistent false radar returns showing up in that area.