Rainy Season = Hurricane season
This means anything could happen - no guarantees
Some Days are Beautiful others wet
Some Rainstorms go over the island quick & then it dries up fast, others pour down and stay
Check the weather site on this Home page in the column on the left for some info
If you know what month you want to go you might get a more accurate report of typical weather during that month. Also you could check out Belize Climate for weather over time.