We have Hurricane Season, which lasts from June through November.
We also have Wet Seasons and Dry Seasons. I have lived in the Caribbean many years, but I haven't lived here long enough to know the timing in the DR for sure, but think it is Wet Season here from about June through August, and then again in Oct and November, but dry (or lots drier) usually from December through April.
Ask a camposino, and he would know in a minute, and tell you because he is in touch with Mother Nature here. Most City dominicanos, most gringos and most europeans here won't have a clue, or will try to compare seasons in the Caribbean to the seasons in New York or Bonn.
Hope this helps you.