All those whirling wind turbines out there are causing havoc with weather radar, or so says the Associated Press. "Some wind farms have appeared on Doppler radar as either a tornado or a violent thunderstorm," wrote Dirk Lammers. "The National Weather Service received a frantic warning from an emergency worker in Kansas who had access to radar images and thought he’d seen a tornado. What he actually saw was an image of wind turbines with fast moving blades."
This is a case where a human eye is better than a computer. The turbines can set off an automatic alert from a Doppler radar. (Wind farms built within 11 miles of a Doppler site seem to have the biggest effect.) But when a real, live weather person looks at the screen, she can tell a real tornado from a blip caused by turbines. Software can remove stationary obstacles — mountains, buildings — but there is no fix yet for removing moving turbines.
Weather people are aghast that anyone trained on reading a radar would be fooled. However, it appears that the Royal Air Force's air traffic radars have been fooled, too.