63ChevyII: I love those charts too! They're a great tool for comparison.
tekewin: I know what you mean about altitude being a whole separate animal. It doesn't generally affect me much, but once I pushed kinda hard on Whitney (it's really tough running the switchbacks, and even worse above Trail Crest) and things started to go dark every now and then with tunnel vision...I'd slow down and the light would return, I'd speed up and it would get darker and darker...wacky. BTW if you're doing Skyline this Saturday I just might be out there myself. It's always fun to meet in person on the trail.
jamesgiel: A note on the weather in May - here's a link to the daily averages for Palm Springs in May. It may help to guess how to prepare a bit more in advance, though if you look at the average highs, they're all around the threshold that Cynthia had mentioned, and of course the record highs are astronomical.
http://www.weather.com/weather/wxclimat ... imoMonth=5
If you want to do the prep work, you could even come down in fairly high temps as long as you have lots of extra water cached along the way in advance. I've done that and just kept spraying myself with mist the whole way. It actually works really well. It's kind of funny to be cold when it's blazing hot outside, but it is an effective solution to the problem.
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