Why is the tornado season cyclic? Tornadoes actually don't have a season per se, but can occur any time and anywhere. However, they are more common in the springtime when the jetstream brings together warm moist air (such as from the Gulf) and cold dry air (such as from the Arctic). When winds at higher altitudes blow in the opposite direction of the winds near the ground, rising warm air gets twisted in the opposite direction and creates a funnel. There's a little more to it than that, but that's the basic concept. You can read more about tornadoes and tornado preparedness here.
|When warm moist air collides with cold dry air and is given a spin by the jet stream,
the result can be a tornado. Figure from NOAA's National Severe Storms Laboratory.
|Tornadoes can happen any time of year. Where are you located on this map?
Figure from passporttoknowledge.com.