[pct-l] snow pack between Tuolumne Meadows and Lake Tahoe

[brick at fastpack.com (Brick Robbins)]

At 06:12 PM 12/16/04, Jeff Moorehead wrote:
>  Ideally, if you knew the April 1st average snow depth, then you could 
> make a much more refined forecast for the zero day. Instead of an 
> estimate using all years of highly varying snowfall, choose those years 
> that had identical snowpack, and refine the estimates using only those 
> data. You need lots of data for this. The web site that dude recommended 
> has data for snow stations that goes way back (I was able to query to 
> 1930 for the Cottonwood Pass snow station).

According to a friend of mine who works for the California Cooperative Snow 
Survey (an organization created to support agriculture..) the most 
important datum effecting snow melt rate is solar radiation reaching the 
ground. Much more so than air temperature, rain, or anything else.

A "wet spring" causes a late melt due to the cloud cover blocking sunlight. 
"Rain" usually slows snow melt due to the accompanying cloud cover.

A deeper base, followed by a clear spring is more likely to clear faster 
than a shallower base followed by a cloudy spring

>   One more question and then I swear that's it. What PCT passes are the 
> critical ones in this regard?

I don't swear to be an expert, but from my 3 trips along this section with 
considerable snow cover, I'd say that the Cornices on Mather Pass make it 
the crux of this section.

Forester is not too bad, because you just climb the snow field west of 
where the trail crosses the path. Glenn was a steep walk up, and Muir was 
downright boring. Pinchot, Silver, Seldon and Dohahue lie somewhere in 
between. This assumes and Ice Axe and some knowledge of how to use it, but 
no crampons or serious boots, and assumes that you are patient enough to 
wait for the snow to soften before heading up the hill.

Personally, I think the stream crossings are much more of a problem than 
snow on the ground. The biggest problem with snow is the sun cups.

YMMV and HYOH



--
Brick Robbins
All that is gold does not glitter, not all those who wander, are lost....