RMS noted that in the 1974 Super Outbreak 315 people were killed, more than 6,000 were injured, and over 27,500 buildings were damaged. The event developed to the southeast of an extratropical low-pressure system near the Iowa-Illinois border, spawning 148 tornadoes across 13 states and impacting 900 square miles in less than 18 hours. As many as 15 destructive tornadoes occurred simultaneously during the outbreak.

Kyle Beatty, RMS meteorologist, said, "The scale of the geographic area affected by this outbreak is unmatched, and therefore is often viewed as a worst-case tornado event. However, despite the record loss potential of a recurrence of the 1974 outbreak, there are events that could cause substantially greater catastrophic loss.

"Many major metropolitan areas in the Midwest and South had the potential to be hit by tornadoes in the 1974 event but were spared. If several of these metro areas were struck by significant tornadoes in the same outbreak, the loss could surpass the 1974 recurrence estimate by several times."

The full 10-page report on impacts from the 1974 Super Outbreak and RMS' reconstruction of the event is available online at <http://www.rms.com>.

Founded at Stanford University in 1988, RMS serves clients from offices in the U.S., Europe and Japan.