I think you might be on to something: I am by no means a weather enthusiast or expert, nor do I live in California: the El Niños building up in 1997 and 2015 had similar seasons, 2023 not, the current fast onset and wave seasons (durable good surfable waves in winter) match especially well with 2015. 2023 was the exception but also slower onset. Also La Niña winters also had good winter conditions, but not as durable. So good surf conditions in NorCal outside of La Niña winters might be a visceral leading indicator for fast onset El Niño.