915 AM PST THU FEB 7 2008
 
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ZONE AVALANCHE FORECASTS
* OLYMPICS- WASHINGTON CASCADES NEAR AND WEST OF THE 
CREST- WASHINGTON CASCADES EAST OF THE CREST- MT HOOD 
AREA-

...AVALANCHE WARNING THURSDAY AND FRIDAY...


HIGH avalanche danger below 7000 feet Thursday 
continuing Friday.

SNOWPACK ANALYSIS
Another strong front early Thursday brought an additional 
12 to 20 inches of new snow to most areas both west and 
east of the crest, the Olympics and Mt Hood area since 
Wednesday morning. Very strong winds and slightly warmer 
temperatures produced a widespread natural avalanche 
cycle early Thursday morning. Natural slides were 
reported on Stevens, Snoqualmie and White Passes near the 
frontal passage as temperatures peaked. Some cooling has 
lowered the danger slightly later Thursday morning; 
however continued very strong winds and heavy snowfall 
are building new unstable layers over a deep and 
unconsolidated snowpack containing multiple weak layers 
within the upper 2 to 4 feet. Also, large unstable 
cornices have been building over the past few days. Any 
cornice failures are likely to trigger avalanches on 
slopes below, with some large releases possible. 

Large slides have been seen from both explosive control 
as well as naturals over the past several days. Some 
large slides of 15 to 20 ft deep were seen on Mt Hood in 
Heather Canyon early in the week. These slide paths have 
refilled with new wind deposited snow. Some large 
unstable wind slabs are likely existing over weaker lower 
density snow deposited earlier in the storm cycle. Deep 
unconsolidated snow and slow travel can be expected in 
sheltered terrain. 

THURSDAY AND THURSDAY NIGHT
Very strong crest level winds and moderate to heavy snow 
showers are expected Thursday and Thursday night. This 
should continue to build unstable new wind slab layers to 
an already very deep and unconsolidated snow pack. Also, 
large cornice formations should continue to build along 
ridges. Natural or triggered avalanche should be likely 
on Thursday. We are not recommending back country travel 
in avalanche terrain Thursday through Thursday night. 

FRIDAY AND FRIDAY NIGHT
Warm frontal moisture and continued strong westerly flow 
should maintain moderate to heavy orographic snowfall 
along the west slope areas and continue to build large 
unstable wind slab layers, especially near ridges and on 
mainly northeast to southeast facing slopes where the 
greatest danger should remain. Warming with additional 
snow and or rain late Friday night should lead to another 
natural avalanche cycle by early Saturday. Back country 
travel is still not recommended Friday and Friday night. 

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