[pct-l] Fwd: [Weather and Climate News] March 9, 2009

[Postholer]

> Northern Sierra 8-Station precipitation index:  98% of average (36.0").
> Southern Sierra 5-Station precipitation index: 105% of average (32.0").

Don't be misled.

The key word here is 'precipitation'. SWE is what the hiker is interested 
in, not precip. Precip is the total amount of water, much of which soaks 
into the ground or runs-off before and during snow coverage. SWE measures 
the amount of frozen water sitting on the ground.

Here's an excellent example of the possible disparity using Mumbo Basin 
sensor on 3/9:
Precipitaion:    35.27    35.57    100% of normal
SWE:              11.87    29.43    40%  of normal

While Mumbo basin has received the normal amount of precipitation only 40% 
of that has manifested itself as 'snow'. This strongly suggests warmer 
temperatures at that location, which would reflect the current La Nina (and 
of course global warming ;)

-postholer
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