"Land slides: What we have observed is that some of the larger land slides don't take place until the earth starts to dry out after a set of big storms."
I have heard a surprising number of landslides in the Big Sur basin this summer while hiking on Pine Ridge Trail. I couldn't spot them (can't even see the forest because of all the trees), but they sounded to be big enough to be quite unpleasant if you were under one. So rockslides seem to be a hazard, albeit a small one, all year round. Trees represent a much bigger threat during a storm, as they always seem to make an effort to come down on trails.