Photographing Mavericks starts with a lot of planning. Forecasting starts days before the waves actually hit. Ocean swell that produces the breaking waves is generated from massive storms around the Aleutian Islands. It takes days for the swell to move from the waters of Alaska to the central California coast. We watch models generated from a limited sample of weather equipment across the Pacific, including now a satellite that measures the height of open ocean swell.
The models predict what the swell is. They aren't all that accurate, but they do provide enough data to tell us if waves at Mavericks are possible. More often than not, the models are wrong, and the waves are smaller than projected.
24 hours ahead of time, accuracy gets a bit better. Pro surfers from around the world make a call whether or not to book a last minute flight at this point.
We can forecast wave size with almost 100% accuracy once the swell hits the NOAA buoys off the coast of Oregon hours before it reaches Half Moon Bay. We look for a very specific swell height, period, and direction. This is the moment the surfing world decides to rally.