Dave Dasgupta, a spokesman for ISO, said the "last two first quarters had mild winters. They were very mild compared to this year's."

He told National Underwriter, "We certainly were hit hard by Mother Nature this first quarter, and we had very harsh winter storms that were devastating."

PCS also revised its catastrophe loss estimate upward for all of 2002 to $5.85 billion--$50 million above the original estimate. ISO defines a catastrophe as an event that causes at least $25 million insured property losses and affects a significant number of property-casualty policyholders and insurers.

Among the five catastrophes in the 2003 first quarter noted by ISO, three were winter storms carrying ice, freezing rain and snow that affected 15 states and caused $1.1 billion in insured property damage. The other two were wind and windstorm events, including tornadoes, heavy rain and hail, that were responsible for $365 million in insured losses. Put together, these five events affected 25 states overall, ISO said.

The state that suffered the worst loss was Colorado, which sustained an overall insured loss of $315 million in the quarter from a mid-March winter storm. The runner-ups were Maryland at $165 million and New Jersey at $130 million. Both New York and Pennsylvania each suffered $105 million in property damage, ISO said.