Storm Chasing - Geographic and Seasonal Activity

Geographic and Seasonal Activity

Storm chasers are most active in the spring and early summer, particularly May and June, across the Great Plains of the United States (extending into Canada) in an area colloquially known as Tornado Alley, with many hundred individuals active on some days during this period. This coincides with the most consistent tornado days in the most desirable topography of the Great Plains. Not only are the most intense supercells common here, but because of the moisture profile of the atmosphere, the storms tend to be more visible than locations farther east where there are also frequent severe thunderstorms. There is a tendency for chases earlier in the year to be farther south, shifting farther north with the jet stream as the season progresses. Storms occurring later in the year tend to be more isolated and slower moving, both of which are also desirable to chasers.

Chasers may operate whenever significant thunderstorm activity is occurring; whatever the date. This most commonly includes more sporadic activity occurring in warmer months of the year bounding the spring maximum, such as the active month of April; and farther north especially, the summer months. An annually inconsistent and substantially smaller peak of severe thunderstorm and tornado activity also arises in the transitional months of autumn, particularly October and November. In the area with the most consistent significant tornado activity, the Southern Plains, the tornado season is intense but relatively brief.

Some organized chasing efforts have also begun in the Top End of the Northern Territory and in southeast Australia, with the biggest successes in November and December. A handful of individuals are also known to be chasing in other countries, including Israel, Italy, Spain, France, Belgium, the Netherlands, Finland, Germany, Switzerland, Bulgaria, Estonia, Argentina, and New Zealand; although many people trek to the Great Plains of North America from these and other countries around the world (especially from the United Kingdom).