The National Weather Service said it received several reports of tornadoes beginning in the Alexandria area to Meeker County. In a news item on its Web site today, the Weather Service said atmospheric conditions were too dry for tornadoes and the spotted reports were actually "gustnadoes."

"A gustnado is a rotating column of air that forms as a result of turbulence along a thunderstorm gust front boundary. Gustnadoes are associated with shelf clouds, a cloud structure that is often confused with a wall cloud, which is sometimes a tornadic cloud feature. A gustnado is not a tornado, and it is not dangerous.

"On Saturday evening, the gust front boundary was clearly evident in radar data from the Chanhassen Doppler radar, and often, many of the reports occurred several miles ahead of the main area of precipitation with the squall line, which is where the gust front was located. As the shelf cloud associated with the squall line moved over the NWS office in Chanhassen, meteorologists observed the turbulence within it, seeing how it could be confused with a more dangerous wall cloud feature and consequently, result in the volume of tornado reports."

Source: www.crh.noaa.gov/mpx, Top News of the Day