Snakes: striking distance is a lot shorter than your hiking pole. When I was doing field biology in college, the accepted technique was to carry a stick to move the critter off gently if it was too close to the trail to walk around.
Don't know if that's still the accepted practice for that kind of field work, but it is effective.
Snake page Here's some advice I like
Water: last year I dipt and sipt the whole west side of Kaweah Gap, from Mehrten on, and had no problem.
Lightning: seems to boil down to get low, don't be the highest point around, and don't be near the highest point around, and that includes in an overhang under a prominent point, a lone or unusually tall tree, a prominent rock or outcrop: there's plenty of discussion on the two Whitney sites and other reliable places such as USFS and NPS sites for the area you are going into.
