Read the weather forecast daily. Go to www.weather.gov and ask for Lone Pine, CA. Down in the bottom left corner of the Lone Pine forecast page, click Forecast Discussion. It's worth reading. Here is todays:

Quote:
.SYNOPSIS...Monsoonal moisture will be on the decrease starting
today, which will bring a downward trend in thunderstorm activity
starting today. Heavy rain threat still exists for this afternoon,
mainly over the Great Basin, then should be less of the a threat by
the weekend. Showers and thunderstorm chances should be limited to
the higher terrain by Sunday. Dry and sunnier weather should settle
in by the middle of next week a ridge of high pressure builds into
the Southwestern US. Temperatures will be return to near normal by
the beginning of next week.


Also, thunderstorms tend to be afternoon events. Start early enough to leave the summit by noon or sooner.