How far in advance should I buy airline tickets?

You should buy your ticket about 3 to 6 months ahead of time to get the best fares and flight times that you prefer. If you wait until 2 months or less then you may get lucky, but more than likely you will end up paying more and having trouble getting the seats or flight that you want.

From Nashville you will have to fly to Atlanta (Delta) or Miami (American) and change planes. Then you fly on to St. Thomas, USVI. From the St. Thomas airport you take a taxi to the ferry and then a short ferry ride over to St. John. So it is a long trip and you need to leave Nashville early if you want to make it all in one day.

August is the off season in the islands and so they are less crowded which is good for you. You will want to rent a car on St. John. It is mostly undeveloped National Park Lands. Enjoy hiking the many trails, exploring old sugar plantation ruins, snorkeling, swimming, relaxing on the beach. Get up early and explore the island while the temps are not so hot and then relax at your resort in the afternoon. The ferries bring many daytrip people from the cruise ships over from St. Thomas, but if you get to the beach early you can have the place to your self for a few hours.

Dining options are limited and expensive, but generally very good. You won't go hungry. If you don't mind cooking and have a villa with a kitchen you will save a lot of money and there is a grocery store with most everything you would find back home.

At least 5 months ahead. As for things to do. For beaches. Cinnamon Bay and Trunk Bay are very nice. If you want to snorkel, Trunk Bay is the place. It is rated high on the list of top world snorkeling spots and it is operated by the National Park Service. There is a trail with signs that tell you some of the things you are looking at in the water. You can also snorkel at Cinnamon Bay but it isn't anything great. The best thing to do is to charter a catamaran for a day. I recommend Singing Dog Sailing who operates a 46-foot boat and it is $1500 a day for up to 6 people and then every person after that is extra. They will serve you breakfast which is usually cinnamon rolls and a fruit plater and will also serve lunch if you want. You can chose to do the BVI tour and go to a snorkeling spot and then make your way to Jost Van Dyke. You can have lunch at one of the island's two world famous restaurants, The Soggy Dollar Bar or Foxy's. For restaurants on St. John I recommend the Beach Bar, The Spyglass which has great desserts, Morgan's Mango for dinner which is great but a little expensive however it's worth it. I would recommend to rent a house instead of staying at the very expensive Westin. We rented Colibri which is very close to town, overlooks Great Cruz Bay, and also overlooks millionaire Mr. Susman's, husband of Shellie Pingrey who is a Maine Congresswoman. Have fun in St. John

There is no advantage to buying tickets ahead of time anymore. In fact, many sites offer last minute prices to fill empty seats. Weather. You can check online as to hurricanes in the region for August. Hurricanes happen in the tropics past June with the official season, as per the US Weather Service, starting June 1 to the end of November. What to do anywhere information is available online from many sites. Asking here is not recommended. Most US citizens have never been on an aircraft let alone traveled to the Caribbean and to any of the USVI locations. These are beach destinations with the typical resort activities, nature, photography, hiking, water sports, eating and night life events.