From the weather channel we get the following definition: "Derived from mauism, the Arabic word for "season," a monsoon often refers to a rainy season -- but this only describes the weather a monsoon brings, not what a monsoon is. A monsoon is actually a seasonal shift in wind direction and pressure distribution that causes a change in precipitation."
We usually visit Puerto Rico in late October as the monsoon season comes to its end and what we find is that at the beginning of our trip (Oct 24th) it rains most of the day and night but each day has less rain until about November 5th when the rains are completely gone and it is clear and dry for the full 24 hours.
I live in the 49th parallel normally so we don't have any type of rainy season other than fall and the rains are very hit and miss----some years there are minimal rains and other years it seems as if it will never end but at the 49th parallel it is always COLD when it is raining. Here at the 18th parallel it is usually warm when it is raining. The rain actually diminishes the humidity and can be a welcome relief!
Enjoy the monsoon season and pray for a lack of hurricanes!