Tornado Alley chase season does not have an official start and end like Hurricane Season.  The most active time of year for tornadoes in the Central United States is from early April until the end of June.  There is a slight second peak in the fall, around October.  Because I don't live in Tornado Alley, I'm restricted to a few weeks of the season, so I try for the statistical peak, about the second week of May until the first week in June.  If I can extend my chase time beyond two or three weeks, I usually trend toward adding more May days than June.  But each season is different, and each year brings a different departure and return date.

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