With over $1 billion in tornado losses hitting insurers, first-quarter 2008 twister loss totals have blown past comparable first-quarter loss totals for the last four years, A.M. Best reported yesterday.

In a research report, analysts from the Oldwick, N.J.-based rating agency noted that roughly $850 million in first-quarter insured catastrophe losses resulted from the "Super Tuesday Tornado Outbreak" in the mid-South on Feb. 5 and 6, and that about $340 million more came from a Mar. 14 tornado that struck in downtown Atlanta.

The report also said that while hurricanes and earthquakes tend to generate higher losses per event, on average, in each year since 1953 tornadoes and related weather events have caused nearly 57 percent of all U.S. insured catastrophe losses. In 2007, these perils generated 69 percent of the total insured cat losses.