2005: A Strange Tornado Year

As this is being written, preliminary statistics indicates that tornado activity during 2005 was less than usual, with the number of tornadoes across the contiguous United States being slightly lower than the 10-year average (Figure). However, the timing of the tornadoes was quite unusual. Tornado activity during the first four months of the year was slightly below normal with 233 reported tornadoes, compared to the 10-year average of 274. However, these months were unusual in that there were 26 confirmed tornadoes in California, this compares to an average of 4. The previous for California tornadoes during the first four months of the year was 14 in 1991. In May things changed dramatically, rather than a tornado count near the average of 3221, only 134 tornadoes were reported. In May in Oklahoma, the heart of “tornado season” in the heart “tornado alley, no tornadoes were reported during May. This was the first May on record the Oklahoma had no May tornadoes. Nationwide, there were no tornado deaths during April, May, and June. This was only the second time this has occurred in the last 50 years. Tornado activity started in late May over the Northern Plains of the United States (the Dakotas, Minnesota, and Wisconsin). During the summer and early autumn, tornadoes were suppressed over the United States except in the right-front quadrant of land falling hurricanes. However, during the night between November 5th and 6th, a small but deadly tornado outbreak occurred in the western Ohio Valley. Later that month, another, larger tornado outbreak occurred in the same general area on November 15 when 40 tornadoes were reported. Historically, this was the fourth outbreak of 35 or more tornadoes that occurred on November 15. During the presentation, the meteorology associated with the 2005 tornado season will be discussed to show why the pattern was so anomalous.