Sunday, January 20, 2013

Winter on the Snowfield

A strong high pressure system over Mt Rainier led to some incredible weather last week! It felt like summer up at Camp Muir, with clear skies and warm temperatures. Unfortunately the snowfield was hammered by consistent moderate to strong winds, causing significant transport of the relatively dry snow left by the last major storm. The upper snowfield and Cowlitz glacier were laden with heavy sastrugi. and thick sun crusts and ice layers were exposed in many areas, making uphill ski travel difficult at times. The lower portion of the snowfield (below Panorama Point) had heavier snow and was less effected by the wind, and was actually quite enjoyable  to ski. 

Travel to Camp Muir can still be an enjoyable venture, as long as folks bring appropriate equipment to safely deal with the terrain, and are prepared for the harsh weather often encountered during the winter. Ski crampons or a set of light weight boot crampons would have been nice for getting to Camp Muir. If you expect to make use of the public shelter at Camp Muir, be prepared to spend time digging out the doors, as they were nearly completely buried by drifted snow when we arrived. Do not count on other parties to have dug them out recently, and certainly bring at least one sturdy shovel.

In addition to creating heavy sastrugi on the snowfield, the winds and heavy sunlight last week created significant spacial variability in the snowpack around Camp Muir. Some ridgelines had been scoured nearly to the ground, while others had generated large cornices, like those typical of the east side of the snowfield during the winter and spring. A few large wind pillows were noted along the ridgline above Camp Muir heading to the Beehive and Gibralter Rock, whereas other areas of the upper cowlitz were scoured down to last year's snow. We dug a snow pit above Camp Muir, and although we found no major red flags in the snowpack, the huge spacial variability in the area makes it difficult to draw any reliable conclusions about the overall snow stability. If you are going to venture up to Camp Muir and beyond, always get a detailed weather and avalanche forecast before you leave the trailhead, but also know that these forecasts are not an adequate replacement for good observations and decision making. Be prepared to make your own assessments about the safety of the terrain you are traveling in. Oh, and please remember to register for overnight trips so we know you're up there.

Have a great winter, get out and ski, be safe.