The weather forecasts for this area are so inaccurate, it's better just to assume it's going to be warm, humid, and a mix of sun and clouds with occasional rain (mostly at night but not always) every day this time of year.
Sand flies (no-see-ums) are an issue this time of year, so a lot of people swear by baby oil. They can't bite through it. I don't like to get my legs and feet all oily, so I just put up with the bites and complain about 'em later.
Enjoy your stay!