In this edition of "Ask a Travel Expert," dive travel writer Terry Ward has ideas for solo, winter and cavern diving.

Q: Where can I book a quick dive trip to escape the winter doldrums?

A: Any place the water is blue is a good bet for fixing the blues. But if you are looking to warm up while you’re at it, Central America and the Caribbean offer lots to love at the nexus of balmy temperatures and exciting diving. PADI Travel’s Jenna Rushton points to Bonaire and Curaçao for divers who want a mix of shore diving and boat dives (as well as some of the warmest winter temperatures). And don’t overlook Belize, with lots in the mix for nondivers who might be joining you, or Mexico. “Easy trips to Cozumel never disappoint, and offer great diving, good weather and affordable prices,” Rushton says. Winter’s cooler water temperatures in Cozumel bring a marine-denizen favorite in large numbers, says Michael Penwarden, who owns Dive Paradise on the island. “January and February are the height of eagle ray season,” he says—an underwater marvel.

Q: Which caverns can open-water divers explore with a guide?

A: For many divers, caves and caverns in freshwater springs—along limestone coastlines or elsewhere—hold infinite allure. But venturing into overhead environments is extremely dangerous and shouldn’t be attempted without a cavern/cave certification.

You can get a taste for cave diving’s appeal by taking a cavern tour with a certified guide. Some caverns—particularly those with large open-water basins— only require an open-water certification. But, with the exception of a professional cavern tour, you should stay out of the overhead portion entirely unless you’re appropriately trained, equipped and certified. Rushton points to the beautiful freshwater cenotes around Playa del Carmen, Mexico, as an ideal cavern experience. “There are hundreds in the local “There are hundreds in the local area, and the dive guides will be able to recommend which are best,” she says. According to Cave Training Mexico owner, Alessandra Figari, each cavern has its own distinct characteristics.

The best ones for recreational divers near Playa del Carmen include Cenote Tajma Ha, where sunbeams reflect beautifully in the waters, and Cenote Dos Ojos, for the quality and quantity of its formations. The cavern that feels most like a cave in the area is at Cenote Taak Bi Ha— but be sure you have perfect buoyancy and lots of experience as a certified cavern diver before trying it, she says.

Q: What are good places for solo travelers to go on a dive trip?

A: Solo travelers often have the best trips because they make so many friends along the way simply by not being absorbed in the person they’re traveling with (because there isn’t one). Some of my favorite travel memories are from times I went it alone in easy-to-travel spots like Bali and Europe.

Rushton says there are many great spots for solo divers to find buddies and plenty of adventure. The diving hotspot Ko Tao in Thailand, she says, is “great for a cheap trip and caters to a lot of young backpackers.” Among the other well-known diving meccas for single divers she suggests are Roatan and Bonaire.