The photos below come courtesy of Slovenian weather researcher and storm chaser Marko Korosec. His day job is managing a road weather information system for Slovenia's main highway company, and he also does work with the European Storm Forecast Experiment. Naturally, one of his chief interests is America's Tornado Alley, where Korosec took these photos this past summer—specifically Kansas, Colorado, and Oklahoma.
These are supercell storms, which are basically powerful, isolated thunderstorms that also rotate due to an inner vortex known as a mesocyclone. About 30 percent of supercells will kick out a tornado, which is almost all of significant tornadoes, about 1,500 a year in the US.
