Based on the forecast, I wouldn't expect lightening strikes to be a concern, especially not in the mornings. To maximize safety, get an alpine early start and try to get off the summit by noonish and you should be fine.
Most likely you'll just hear some rumbling thunder from cloud-cloud electrical activity in the distance. You probably won't even see a flash, but if you do, count the seconds and use that as a guide to decide. Sound travels at about 5 seconds per mile.
The most common dangerous lightning in the southern Sierra is during afternoon monsoonal thunderstorms driven by hot air from the southern desert in the summer heat. This is a cool fall storm, but don't let your guard down entirely just because I wrote that.
