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I thought this was fairly interesting and gives good information on
snowmelt and there is a lot of ski content in this one...

-Scott

10:09 AM Mon May 09, 2005 EDT

Summit fog at sunset...
Though over 10 inches of snow have fallen at the summit this month, much
of it on light winds, very little remains at the peak this morning. Twelve
hours of perfect snow eating conditions beginning at sunset last night
have begun to spell the end for our summit snowpack.

Perfect snow melt conditions occur frequently in late spring on Mount
Washington. The old phrase, "Itís not the heat, itís the humidity" comes
to mind, as it is true for both humans and snowmelt. Warm, dry conditions
lead to a very slow snowmelt, as the snow can cool itself through
evaporation. As an example, last fall we had 3 inches of snow on the
ground for a week with temperatures in the mid to upper 30s. Humidities
during the period averaged under 20% though, limiting melt.

Snowpack disappears much more quickly when the humidity high, or when in
the fog, because the rate of evaporative cooling slows, and the whole
snowpack can warm up. Add a little wind, which counters and all but
eliminates the insulating effects of the fog, and say goodbye to your
snow.

Through Wednesday, the summit will see temperatures rise into the 50s,
with modest winds and intermittent fog. There is good news though, as just
off the summit there is a lot more snow to begin with than at this time
last year on the snowfields and in Great Gulf. Also, panic for last turns
in by no means near, as the summit has warm foggy conditions almost daily
throughout the spring, and skiing can often still be done in late June.

But imagine how long it would last if we had an semi-arid, West Coast
climate?!?

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