Given that mid-December to mid-April (winter) is the peak tourist season, when rates are substantially higher and beaches and lodgings more crowded, it's best to go in the summer. There is more rain in summer, but it tends to come in downpours that clear as quickly as they arrive.

 Nervous Nellies will tell you that this is hurricane season, but the chances that you'll get swept up in the big one are slim. Even so, it's best to keep an eye on the weather reports in the days before your arrival.