The Newark, Calif.-based modeler says the insured losses from Hurricane Irene in the United States and Caribbean will fall between $2.5 billion and $5.5 billion.

Some insured losses will also come from Tropical Storm Lee, which hit the coast of Louisiana in September.

Modeling competitors Eqecat and AIR Worldwide put the range of U.S. insured losses at between $1.5 billion and $2.8 billion, and between $3 billion and $6 billion, respectively.

Differences in the approach and/or methods to modeling—as well as assumptions made based on a limited amount of data—could account for difference in the estimates.

Karen Clark & Co. has come up with a $3 billion loss estimate for the insurance industry after using RiskInsight, a new tool the company developed.

Verisk Analytics' Property Claims Services projects a $4.3 billion tab to then insurance industry from Irene.

The 2011 Atlantic hurricane season ended after a second-straight year of 19 tropical storms but, unlike 2010, this year included a hurricane landfall—the first since Hurricane Ike in 2008.

Of the 19 named storms, seven became hurricanes and three became major hurricanes. No major hurricanes made U.S. landfall this year, marking the sixth-straight year in which no storm of Category 3 or greater has hit the U.S.