I use www.timeanddate.com to calcuate daylight and especially moonlight hours - set it to Fresno and get pretty accurate values for the central Sierra

Below my last search to see if I can cheat daylight in October and hike on each day under a rising bright moon, and as it turns out, I could pull that off in the first 2 weeks of October 2011:

http://www.timeanddate.com/worldclock/as...l=-11&day=1

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