Has anyone sailed the Grenadines in the first half of May? One of our boats will not have A/C, so I just want to be prepared. When we sailed there many years ago in June it was quite hot.

For the Grenadines in May:
Average Daily Temp - 79 F.
Average Low Temp. - 77 F.
Average High - 88 Average Daily Relative Humidity - 75% .
Average Monthly Rainfall - 3.1"
Number of Days with some rain - 12

If you want more detailed statistics go here:
https://www.wunderground.com/weather/vc/bequiao www.wunderground.com
Click on the Almanac section then search history for May. You can find data for actual weather in the Grenadines for every day in May during the last 10 years.

Thanks a lot - I appreciate the link!
Also wondering how other sailors have fared without A/C during that time.

It depends on where you are anchored/moored, wind direction and speed and how good the cross ventilation is on the boat. That said, we used fans in our cabin to help circulate the air it wasn't "cool" by any stretch of the imagination.