Dan_Miller Posted May 13, 2008 Share Posted May 13, 2008 BACKCOUNTRY AVALANCHE STATEMENT FOR THE OLYMPICS WASHINGTON CASCADES AND MT HOOD AREA NORTHWEST WEATHER AND AVALANCHE CENTER SEATTLE WASHINGTON 830 AM PDT TUE MAY 13 2008 NWAC Program administered by: USDA-Forest Service with cooperative funding and support from: Washington State Department of Transportation National Weather Service National Park Service Washington State Parks and Recreation Commission Pacific Northwest Ski Area Association Friends of the Avalanche Center and other private organizations. This statement applies to back country avalanche terrain below 7000 feet and does not apply to highways or operating ski areas. WAZ513-518-519-019-042-501-502-ORZ011-141700- && ..RAIN AND SIGNIFICANT WARMING TO PROVIDE SUBSTANTIALLY INCREASING AVALANCHE DANGER THIS WEEK... With the exception of a few periods of brief warming, an unusually cool and snowy spring has been experienced in the Northwest to date. This has produced periods of great late season powder while maintaining a mostly stable and generally refrozen mid snowpack below a diurnally developing layer of moist to wet snow or slush in the upper 1 to 3 feet of near surface snow. Field reports have indicated surface snow conditions ranging from the good-a few inches of recent soft snow over a firm base, to the bad-a trap crust over mush, as well as a variety of conditions in between. The overall cool conditions have produced some, though rather limited spring avalanche activity as daily warming has slowly warmed and weakened near surface snow. Most meltwater percolation and associated snowpack weakening have been confined to upper snowpack layers, at least at mid and upper elevations above about 4 to 5000 feet. However, this rather benign spring snowpack evolution is expected to change significantly this week, when rain at slowly rising freezing levels Tuesday into early Wednesday should be followed by sustained high freezing levels reaching 13,000 to 15,000 feet later Wednesday through Saturday. These prolonged and unusually high freezing levels for May are the highest since last summer. In any case, rainwater weakening and lubricating of near surface snow Tuesday should be rapidly followed by increasing amounts of meltwater percolating into and weakening progressively deeper snowpack layers. Combined with some early winter faceting and weakening of several layers near the ground, this sudden and sustained warming of the Northwest snowpack should result in a significant spring avalanche cycle, with some slides possibly involving all of this past winter's snowcover. An increasing moderate to considerable avalanche danger from rain on Tuesday should precede a considerable to locally high danger expected to develop in many areas mid-late Wednesday through Saturday. While the rain affected danger increase should develop on all exposures, sun and warming related danger should initially develop most significantly on southeast through southwest exposures Wednesday and Thursday. However, its cumulative effects should progress to most exposures and to increasingly high elevations later Thursday through Saturday due to the combined effects of very warm temperatures, high sun angle, substantial snow melt, light winds and only minimal overnight refreezing of surface snow. Due to the evolving danger, a variety of avalanches are likely and should range from initial small wet loose releases to increasingly large wet loose or wet slab slides, with some isolated slides possibly extending full path length or more, and some extending into relatively flat terrain runouts. As a result, back country travelers from climbers to snowmobilers, skiers to snowboarders, hikers to snowshoers, should all exercise increasing caution in avalanche terrain Tuesday and Wednesday, with travel in steeper avalanche terrain not recommended Thursday through Saturday, especially on slopes not experiencing recent avalanche activity. Travelers should be especially cautious on slopes with overhanging cornices or below icefalls, which may become very active later this week, and may be the trigger for some of the larger slide releases expected. This statement will be updated as conditions warrant. && Quote Link to comment Share on other sites More sharing options...
ashw_justin Posted May 13, 2008 Share Posted May 13, 2008 Combined with some early winter faceting and weakening of several layers near the ground, this sudden and sustained warming of the Northwest snowpack should result in a significant spring avalanche cycle, with some slides possibly involving all of this past winter's snowcover. That would be a sight to see... from a safe distance. Would love to see photos if anyone sees it happen (I think I'm gonna pass anyway--skiing megamush would blow even if it weren't dangerous). Quote Link to comment Share on other sites More sharing options...
ivan Posted May 13, 2008 Share Posted May 13, 2008 hey, it's gonna be 90 on friday - how bad could it be? Quote Link to comment Share on other sites More sharing options...
armin Posted May 13, 2008 Share Posted May 13, 2008 Thanks for this. Quote Link to comment Share on other sites More sharing options...
KaskadskyjKozak Posted May 13, 2008 Share Posted May 13, 2008 that puts a damper on a lot of routes :-( Quote Link to comment Share on other sites More sharing options...
Bug Posted May 13, 2008 Share Posted May 13, 2008 that puts a damper on a lot of routes :-( More like damp slush. Quote Link to comment Share on other sites More sharing options...
mike1 Posted May 16, 2008 Share Posted May 16, 2008 There goes my plans... Quote Link to comment Share on other sites More sharing options...
olyclimber Posted May 16, 2008 Share Posted May 16, 2008 anybody have a favorite place to go with a high possibility of viewing big avalanches from relative saftey? (not human caused avies). Quote Link to comment Share on other sites More sharing options...
Billygoat Posted May 16, 2008 Share Posted May 16, 2008 Mt. Baker Ski Area White Salmon Lodge Parking lot Quote Link to comment Share on other sites More sharing options...
G-spotter Posted May 16, 2008 Share Posted May 16, 2008 anybody have a favorite place to go with a high possibility of viewing big avalanches from relative saftey? (not human caused avies). duffy lake road - which is closed right now with avvy debris blocking the road Quote Link to comment Share on other sites More sharing options...
Raindawg Posted May 16, 2008 Share Posted May 16, 2008 anybody have a favorite place to go with a high possibility of viewing big avalanches from relative saftey? (not human caused avies). From the Index Town Walls, I've seen MASSIVE avalanches come off the North Side of Mt. Index, especially down the chute between the North and Middle Peaks. It looked like Niagra Falls. Also, I've seen giants come off of Eagle Peak in Mt. Rainier National Park across the road from Cougar Rock Campground (near where you do the log crossing of the Nisqually. The blast can knock your hat off. Quote Link to comment Share on other sites More sharing options...
pms Posted May 16, 2008 Share Posted May 16, 2008 better yet, lake serene picnic Quote Link to comment Share on other sites More sharing options...
Lowlander Posted May 16, 2008 Share Posted May 16, 2008 (edited) Or from the base of Ice Cliff glacier on Stuart to see the ice cliff break off, cornices falling, and ice/rock fall. Great sight to see, just witnessed it. Edited May 17, 2008 by Lowlander Quote Link to comment Share on other sites More sharing options...
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