Understanding Southern California Wave Direction
Waves are made from wind. That wind can be close to shore and form what we call windswell.
However, a strong storm, like a hurricane, can send waves from far away resulting in larger waves and longer swell periods.
Wind + Wind Strength + Wind Distance =
Longer Swell Periods
Here are some basic facts about the wind and waves that I have been thinking about: The harder the wind blows, over a longer period of time, over a greater distance, the more energy will be transferred (into the ocean).
Resulting in larger waves and longer swell periods.
Swell period is related to how deep the swell energy extends below the surface of the ocean.
The longer the swell period, the deeper the swell energy.
The more the waves will be influenced by underwater bathymetry (the shape of the bottom of the break) and shallow offshore banks.
Hurricanes: Like Warm Water
Hurricane swell direction begins out of the Southeast as the storms move from underneath Baja, Mexico (from warm water).
The swell shifts more South and Southwest as is moves further West.
Hurricanes need warm water (about 80 degrees) to fuel the storm and thrive—this is why El Nino years are good for swell.
El Nino years have warmer water and thus spin off more hurricanes with longer vector and a closer proximity to California.
Read the complete article on surfline. explaining the surf mechanics of Malibu and other great information about wave mechanics and historical photos.