(FORTUNE Magazine) – The hurricane season is here again, insurance companies are trapped in Florida, and the long-range weather forecast is not particularly sunny. By studying such factors as rainfall patterns over Western Africa, William Gray, a scientist at Colorado State University, has developed a reputation for accurately predicting the number of hurricanes that will form each year in the Caribbean, mid-Atlantic, and Gulf of Mexico (see chart). What's in store this year? Last month Gray told FORTUNE he expects seven hurricanes to form -- more than normal. What Gray cannot foresee is whether they will strike land and, if so, where. That is only modest comfort to insurers. Hurricane Andrew did $16.5 billion of damage in Florida and Louisiana last August. As a result, ten insurers went under and 34 were driven from the market; those that remain are still reeling. Many companies feel that they are overexposed in the South Florida market and want to reduce their levels of coverage. But Florida passed a law forcing them to renew hurricane insurance policies when they expire, at least until November 19, after the storm season has ended. Allstate Insurance, which took a $2.7 billion hit from Andrew, originally planned to unload 300,000 policies over the next two years but has agreed to abide by the moratorium. Prudential Property & Casualty Insurance, however, plans to challenge the moratorium in federal court. Says Laurita Warner, a company spokesperson: ''Our capital base of $600 million was more than twice wiped out by Andrew. We had to get an infusion of cash from our parent company. Another Andrew would be devastating for us.''

CHART: NOT AVAILABLE CREDIT: FORTUNE CHART/SOURCE: WILLIAM GRAY, COLORADO STATE UNIVERSITY CAPTION: STORM WATCH