NOAA has nearly everything, you just have to look around to find stuff.
You can also change the location to reflect higher altitudes and therefor more accurate temperatures on top of the mountain. On the 7-day forecast for a location there is a little google map with a green zone on the righthand side. If you move the map to the top of the mountain and click, it will move the zone to that higher elevation.
Thanks everyone - I've bookmarked all these sites!
Can you tell I'm looking for snow? LOL