How do they form and can they be predicted?
The idea that tornadoes may form as a result of warm moist air colliding with cold Canadian air and dry air from the Rockies is a gross oversimplification. Many thunderstorms form under those conditions, which never come close to producing tornadoes. Even when the large-scale environment is quite favorable for tornadoes, not every storm spawns one. Instead, tornadoes form via complicated storm-scale processes which depend on the interaction of the storms internal dynamical structure including its forward and rear flank gust fronts (see below) with the influx of buoyant, sheared air immediately around and under the rotating updraft (mesocyclone) within the storm. In fact, recent theories suggest that the temperature and moisture characteristics of the rear flank downdraft of a supercell are very important in spawning a tornado. Although prediction of the exact location and intensity of tornadoes is difficult, atmospheric conditions associated with the formation of the parent severe stor
The idea that tornadoes may form as a result of warm moist air colliding with cold Canadian air and dry air from the Rockies is a gross oversimplification. Many thunderstorms form under those conditions, which never come close to producing tornadoes. Even when the large-scale environment is quite favorable for tornadoes, not every storm spawns one. Instead, tornadoes form via complicated storm-scale processes which depend on the interaction of the storms internal dynamical structure including its forward and rear flank gust fronts (see below) with the influx of buoyant, sheared air immediately around and under the rotating updraft (mesocyclone) within the storm. In fact, recent theories suggest that the temperature and moisture characteristics of the rear flank downdraft of a supercell are very important in spawning a tornado. Although prediction of the exact location and intensity of tornadoes is difficult, atmospheric conditions associated with the formation of the parent severe stor
