After a busy start, tornado events in the U.S. in 2012 have dropped well below the expected norm. The preliminary total of 757 tornadoes through late September 2012 is about 400 tornadoes below what might be expected in a "normal" year. The chart above shows that at this time in 2011, the annual running total was over 400 tornadoes *above* normal; nearly opposite of this year. The chart is meant to depict the dramatic variability that can occur in tornado numbers from one year to the next.
Click for full resolution image.
