THE sunny skies and clear waters of summer are here again. For newcomers who think it’s the rainy season in Costa Rica, look at a map, find the Caribbean coast and think “dry season.”September and October are normally the driest months of the year on the Caribbean. The lack of rain in the rivers and creeks, combined with board flat seas, clears the ocean waters of sediments and surfers on the southern Caribbean coast, from Cahuita to Punta Mona.These conditions usually provide the best coral reef diving of the year in Costa Rica. Snorkeling and diving are as easy as walking into the ocean right now in the Caribbean. Kilometers of fantastic reef can be found just steps off the beach. The jungle reaches right to the sand in most places, and you can find your own private beach – animals only – without much searching. It’s a diver’s dream, and it’s only about four hours’ drive from rainy San José.The diving is so nice that you do not need tanks or even to dive down – just float above and watch the show go by. I like to put my mask half in and half out of the water and take in rain forest and coral reef in the same view. Many species of coral and fish are easily visible over hectares and hectares of shallow reef.If you do dive down, the bright sand and colorful reef make an excellent place to practice free diving while watching wildlife. You can pick your depth, glide down along coral walls and see much more life than is visible from the surface.You might even be able to hang out with a local and watch how lobster is caught Caribbean-style. If you’re up to it, try staying down as long as the lobster diver.If you still can’t get enough, put on a tank and head down for an hour or more, cruising through the mazes of patch reefs right off the beach. You can spend years diving these reefs and still not see it all. If you still want more, then it’s time to go deeper. Offshore lie kilometers of coral shoal that drop straight down in vertical walls, canyons, crevices and caves to beyond recreational dive limits.Here is the best chance to run into big stuff. Your tank’s air doesn’t last as long when you dive deep, and you might use up that air even faster in the excitement of happening upon a big jewfish or shark. Intricate coral and sponge structures and their great biodiversity are down below the effect of the waves. A tank on your back is the best way to spend time checking out this amazing ecosystem.Make sure you are certified and go with a guide. If you have never tried scuba, take an introductory course and make a shallow dive within a couple of hours. If the fever hits, you might want to take a few days to do the entire certification course.On the Pacific, rains are murking up diving except at Coco and Caño islands, both of which report a lot of excellent blue-water days. For information or to contribute to this report, call 835-6041, email shawn@ costacetacea.com or check out www.costacetacea.com.