Saba is only about 30 miles or so south of St. Martin so it is just as prone to hurricanes as any of the Leeward islands. Dominica is about 200 miles further south and that still is considered part of the hurricane belt. You can check out some of the hurricane web-sites (stormcarib.com, weathercarib.com, caribwx.com are a few good ones) to get historical data showing how often a particular island has been affected by hurricanes. FYI, officially Hurricane Season in the Caribbean runs from June 1 through November 30 with the most active period being September 1 through October 15. The further you get away from the "active" period the better your chances are of avoiding a major storm (of course these are just averages and stoms can occur almost any time - case in point hurricanes were particularily active in August 2004.

I concur with Sunnyboy regarding hurricanes. Saba has had it's fair share since I've been here, but it's not as if the island gets hit by a storm every year.

Regarding the rainy season, which is mostly in the winter, the rain does not affect tourism. It rarely rains all day long.