Over Labor Day weekend, the leftovers of Hurricane Marie threw a giant south swell at Southern California, and the whole coast felt it. The storm itself never came close - it stayed 700-plus miles to the south and west - but the long-period energy it fired off put High Surf and Coastal Flood advisories on the map through Tuesday, and set off a chain reaction that touched water temperature, visibility, the shape of our favorite coves, and even what showed up on the reef.

The swell that worked Southern California over the holiday weekend - Saturday through today, Monday, September 7 - was a strong south to south-southwest swell thrown off by Hurricane Marie. What made it worth writing about was not the size so much as how directional it was. Some beaches got hammered while a cove a few hundred yards away sat almost calm. That is the whole story of this swell, and it is a good lesson in how to read a south swell as a diver.