Severe Tornado Outbreaks
defined as outbreaks with:
≥ 2 long-tracking tornado families
each family w/ ≥ 2 (E)F3+ tornadoes
each of these w/ path lengths ≥ 25 mi
these families over wide geographic area
Examples:
19–20 February 1884
28 March 1890
29–30 April 1909
28 March 1920
9 May 1927
21–22...