A New Wave in Forecasting : Surfing: Sean Collins’ Wave-Trak can predict wave heights within a foot. He and competitor Surf Line mean that information is only a phone call away.

When he began tracking storms in the Pacific Ocean in the late 1970s, Seal Beach surfer Sean Collins was just trying to figure out how he could catch the best waves on the beaches of Baja.

He hardly imagined that a decade later he would be a key player in Orange County’s burgeoning surf industry and a veritable guru who--for better or worse--has revolutionized the quest for the perfect wave.

Collins, soft-spoken and modest, is California’s leading practitioner of the emerging art of surf forecasting. Using an intricate blend of high technology, oceanography and surfing theology, Collins can predict wave heights within a foot up to 10 days in advance for virtually any beach in the world.

For some, such forecasts take the mystery and glamour out of the sport, removing the thrill of uncertainty. But for people who make their living on the waves, Collins and his compatriots in the tiny surf forecasting business are miracle workers.

“It’s a revolution,” said Bill Sullivan, a spokesman for Professional Surfing Assn. of America.

He attributes much of the surfing tour’s success last year--in contrast to the dismal, wave-poor 1988 season--to a schedule based on Collins’ knowledge of surf patterns.

“We sent him the list of sites, and he switched around the times, and every event had at least one day of head-high surf,” Sullivan recounts. “It was incredible!”

Mike Stewart, the world-champion bodyboarder, calls surf forecasts “one of the most valuable tools I can use. My whole life is based on where the waves will be and when they’ll be there.”

For the surfing masses, predictions about surf conditions are just a phone call away. Collins’ Wave-Trak and a competitor, Huntington Beach-based Surf Line, provide recorded forecasts for California beaches via 900 telephone numbers. And if you’re a magazine editor trying to schedule photo shoots in Fiji, or a movie producer making a surfing flick, or a busy executive trying to squeeze surfing in between meetings, then you might want to have Collins on retainer.

“He’s phenomenal!” said Michael Tomson, a former professional surfer and founder of Gotcha Sportswear in Costa Mesa. “I’ve made many trips to many parts of the country on his word, and he’s always come through.”

In its simplest form, surf forecasting is deceptively easy. Swells are produced by winds, and most of the best surfing waves on the California coast are the product of storms far out in the Pacific. Rough predictions can thus be made by tracking the storms on weather maps.

That’s how Collins started out, analyzing the size and intensity of Pacific storms and watching the water to check the time interval between swells--an indicator of whether the waves are building or starting to recede.

Soon, his friends were calling to find out when and where to surf. And then friends of friends were calling. And then strangers.

“I was getting 20 or 30 calls a day from people I didn’t even know, so I figured there must be a way to make some money from this,” Collins said.

In 1985, he read about a surf-reporting service being started by a company called Surf Line. The firm collected information on surf conditions every day from a network of reporters on the beach, and surfers could receive the recorded information with a 75-cent telephone call.

Collins suggested that Surf Line include a forecast as part of the package, and he was hired. The forecasts broadened the appeal of the service, and Collins eventually left to form his own company, Wave-Trak.

Today, Wave-Trak (which also provides surf reports) and Surf Line are tough but friendly competitors. And both Collins and Surf Line meteorologist Chris Borg are refining the forecasting art with sophisticated computer models and a growing array of information sources.

Weather maps, which Surf Line receives via satellite and Wave-Trak gets from a computer hookup, remain the most important source of data. Summer surf is usually produced by storms in the South Pacific, while winter surf comes from the North Pacific.

The location, duration and breadth of a storm, plus the speed of the winds, are the key variables affecting the waves. Storms are tracked with maps that arrive every six hours, and the variables are fed into a computer model that predicts approximately when the swells will arrive in the Southland and how large they will be.

Those results are refined with information from buoys and boats that measure actual swell size and intervals at different points in the ocean. Much of the data is initially collected by the National Oceanic and Atmospheric Administration and distributed by the National Weather Service and various private vendors of weather information.

But oceanographic data also comes from the Navy, satellites and other governments’ weather services, such as New Zealand’s.

Once the exact size, arrival time and direction of the swells are determined, what Collins calls the most difficult part of the process begins: figuring out what the waves will look like on a particular beach. Much of that analysis is based on instinct and experience, but a good knowledge of offshore topography is also essential.

That’s because offshore islands and underwater shelves can “shadow” a swell and turn potentially great waves into little more than ripples. The exact effect of the shadowing, in turn, depends on the depth of the swell, the precise angle at which it arrives and how another set of cross-swells might affect it.

Borg said Surf Line has information about underwater conditions at eight beaches integrated into its computer model and is working to add more.

“The next wave is to bring the forecasts all the way into the beach,” he said.

And much greater precision is certainly in the offing. Already, Wave-Trak and Surf Line claim 90% accuracy, defined as predicting swell size within a foot for a 12-hour period. Together, they field more than 3,000 calls a day, with Surf Line holding about a 2-to-1 lead in market share.

And people who really care about waves are waiting eagerly for even better forecasts.

“Theoretically, if you were in a competition, you could figure out what kind of waves will come through,” Tomson notes. “You could figure, ‘I’ll get two big sets within this 45-minute heat.’ If I were still competing, I’d be thinking about that.”