The water flowed over roads and campgrounds covering several vehicles, and filled them half-full. An example of excessive flooding cam to southeast Idaho in June 1997 from a heavy snowpack. Major flooding occurred along many stretches of the upper Snake River. The largest areas of water inundation reached from Roberts to Menan Buttes and between Shelley and Blackfoot. The Snake River reached its highest natural flows during this snowmelt since 1918.
Tornadoes are rare in Idaho, but they do occur.
Since 1950, an average of three tornadoes a year have occurred. Most Idaho tornadoes have winds between 70 and 130 miles per hour, or about the same strength as winds from a severe thunderstorm. Combined with ground-truth data from volunteer storm spotters, the Doppler Weather radar allows forecasters to monitor the internal structure of storms. The new radar will not only detect the presence and intensity of rain, but also determine the speed and direction of wind within the storms. This latter information, the speed and direction of motion, is essential for identifying atmospheric conditions that typically precede severe and sometimes deadly weather events.