Great beaches. Great surf. But where to go? Ron Hall finds the answer between wind and wave.

This story originally appeared in CondéNast Traveler's July 1996 issue.

Visit Waimea Bay, on Oahu, anytime between May and September and you'll most likely find a haven of peace and tranquility, fishing boats bobbing lazily at anchor, snorkelers patrolling the rocky headlands, and kids splashing at the water's edge. Visit the bay during the winter months, however—November through March—and you'll find it transformed into a fearsome spectacle of ocean power, with waves twenty, even thirty, feet high crowding into the bay, turning it into bands of seething foam. Surfers everywhere talk about Waimea with awe: It is the beach famed for having the biggest ridable waves in the world.

Ridable, of course, is a relative term. Only the elite of the world's surfers even attempt Waimea on a big day, and even then largely in a spirit of bravado. "When surfing Waimea," says the Surfer's Guide to Hawaii, only half jokingly, "it is essential to have the proper crazed attitude that implies a certain reckless disregard for personal safety."

At the time of my visit, Waimea was mourning its latest victim. A young professional surfer named Donnie Solomon, from Ventura, California, had taken off on an eighteen-foot wave just behind the world surfing champion, Kelly Slater of Florida. Slater made it safely to the beach, but Solomon had narrowly failed to push up through the collapsing lip of the wave, was "caught inside," as surfers say, and disappeared under tons of water. By the time the lifeguards reached him, it was too late.

The Jekyll and Hyde nature of Hawaii's beaches, the way they can change character from one season to the next, or even one day to the next, makes writing about them difficult. Take Magic Sands Beach on the Big Island's Kona Coast. Its ample covering of pristine white sand has the habit of suddenly disappearing in certain surf conditions, leaving behind only naked black rock. Once conditions return to normal, the sand magically reappears. Nobody is quite sure where the sand goes in its absences, but they clearly do it no harm. Each time it returns, it has been flushed of debris and is even more brilliantly white than before.

Many other beaches vary with the seasons. In summer, Papohaku Beach on Molokai claims to be the most expansive in all the Hawaiian Islands, occupying two miles of virgin, dune-backed coast at an average width of more than a hundred yards; but in winter the beach narrows to less than half that size. Either way, however, it's a magnificent sight that might have been even more imposing but for the fact that in the 1960s a great amount of its sand was shipped to Honolulu, where it was used to replenish Waikiki Beach, which then, as now, had an erosion problem.

Wind direction and surf levels are the two main factors governing the day-to-day character of Hawaii's beaches. For most of the year, northeast trade winds prevail, but they are punctuated by periods of humid kona weather, when winds come from the south or the southwest (kona is Hawaiian for leeward). Surf levels rise and fall independent of the local weather, often as the result of storms 2,500 miles away in the Aleutian Islands. The geographic isolation of the Hawaiian Islands means there is no intervening land mass to diffuse the ocean swells, and no continental shelf to deaden their impact. Hawaii thus receives some of the most powerful waves in the world—good news, perhaps, for surfing, the sport that Hawaii invented, but it means that swimmers and other recreational ocean users need to select their beaches with care. The map that follows is designed to help them do so.