East coast normally is the face of the wave. Hawaii is the back of the wave. rate of wave movement is timing. thats incredibly simple and I'm sure another more scientific explanation will be on the forum.
You do realize the back of the wave measurement was a joke by native islanders to keep mainlanders away from the waves right? Back of the wave is a useless measurement. Teahpoo would be 2 feet when it's face is 15 feet. You don't ride the back of a wave.
