I have a question to which, I am afraid, I can guess an answer: is the weather hot and 100% humid, i.e. unbearable to the same degree everywhere in the Caribbean? Or is there an island/islands that are a little better that time of the year?

Sea breezes usually mitigate the humidity of the islands in summer to some degree. Typically it is low season there in summer mostly because it is more rainy. Islands like Aruba, Bonaire, Curacaou (sp?), Grenada etc. are typically more consistant in weather all year round.

I was in St. Thomas last August and it was fantastic weather all week. Two little rain showers adn that's it. The humidity was not as bad as where I live in NH and the breeze is constant.

Not a lot different from any other month.

mm

Its a bit warmer but not too bad really. Rain consists of scattered and infrequent rain clouds which don't last long. Agree about the ABC islands. Pretty breezy all the time and more temperate climate. I luv Aruba.You just may too

A few facts you may find interesting:

** The average daily max temperature on most Caribbean islands is 88-90 degrees in July-August.

** You'll never find a combination of 90 degrees and 90% humidity on a Caribbean island.
The daily max humidity usually occurs early in the morning, and as the sun rises it 'burns off' the humidity. Midday humidity averages 50-60% on most islands, somewhat higher on the lush islands than the scrubby ones.

As noted above, the perceived level of comfort (or discomfort) is primarily determined by the tradewinds. The breezes keep people cool (evaporation of moisture from the skin) and comfortable. Still periods and sunless/rainy periods are less comfortable and more humid.