This is the wettest month of the year by far. There are frequent local thunderstorms. However, there are still plenty of clear days. The rains are often heavy with very strong winds at the start of the front. Line squalls occur during this period. The rains aren’t necessarily all day long. Many days have brief showers or no rain at all.
When sailing, be prepared to change to smaller sail when a squall comes. This is the lowest time of the year for tourism. October The is usually the second wettest month of the year. Storms are less frequent and less intense than those in September. You can get a bargain on hotels.