1) The driest coastal region (least annual rainfall) in the Dominican Republic is the southeast portion of the country. This includes the Bayahibe region, an area that is emerging as one of the best places to visit in the country, and the La Romana resort areas.
2) The wettest coastal region (most annual rainfall) in the Dominican Republic is the north coast. This includes the popular Puerto Plata region. One of the rainiest spots in the country is Samana Bay, which of course is a popular place to take whale watching tours of humpback whales so if your focus is seeing these magnificent creatures, perhaps you won't mind the rain so much!
3) The rainiest coastal region of the Dominican Republic gets more than twice the amount of rainfall as the driest region receives. I want to emphasize that north coast gets more than TWO times more rain than the south coast!
4) Saona Island, one of the most popular tourist destinations and only a 30 minute boat ride from the Port of Bayahibe, has even drier weather than Bayahibe. In fact, Saona Island only recieves about one-third the rainfall of what Bayahibe recieves (which is already one of the driest regions in the country). Moreover, Saona Island recieves only about one-sixth of the rainfall that Puerto Plata recieves! This of course does not mean it never rains on Saona Island, but it is definitely a dry microclimate in the Dominican Republic.
5) Obviously, there is a major difference in the amount of rainfall a vacationer may experience depending on exactly where they travel within the Dominican Republic.
6) Vacationers need not worry much about the rain in this tropical paradise because, even during the rainy season, the rainfall tends to come down in spurts of heavy showers followed by the sky opening up again and sunshine flooding the area. It is very rare for an entire vacation, or even an entire day, to be affected by rain. Also, the colors after a rain can be so intense and so beautiful, it can be well worth "sitting one out!"