If the non-hurricane damage is independent, then you expect $(1/n * cost of major hurricane) additional costs next year. In a major hurricane year, you expect (1-n)/n fewer such hurricanes next year. And therefore you expect less expensive damage.

One could debate whether "likely to be worse" is correct. If there's a a major hurricane every 10 years, there's only a 10% chance of it happening next year. The expected value of the damage is higher, but it's still "unlikely" (as in, less than 50%) to happen at all. So it's expected to be worse, but unless there's over 50% chance of a major hurricane per year, it's not likely to be worse.

If year-to-year hurricanes are also independent, then knowing that there was or was not a hurricane this year, it's also no more or less likely that a major hurricane occurs next year then it was looking forward to this year, as of this time last year. But, I don't know if that is an independent thing.

1. Each hurricane is an independent event. Florida expects 5 hurricanes per year on average. There were 0 hurricanes this year, so by definition we can expect more hurricanes next year (because 5 > 0). However, the fact that there were zero hurricanes this year doesn't influence next year's season in any way. The statement is just trivially true.

2. Hurricanes are not independent of each other, but rather get stronger the longer you go without one. So if there were none this year then you will likely bear the brunt of it next season. I know this is a thing for earthquakes and other tectonic activity, but not sure if hurricanes work the same way.

What is meant is that since Florida didn't have a major hurricane this year, then next year is likely to be worse than this year, since Florida has a significant chance of being hit by a major hurricane each year.