Snoqualmie Pass

Cool east winds may delay the sun’s softening of the snow on Thursday. Choose safe travel routes away from slopes containing large cracks and carry equipment to help you navigate firm conditions. If you find that you are in the sunshine and sinking in the snow past your ankle, look for signs of avalanches on steep slopes.

The recent warm spell has created spring-like conditions in the Snoqualmie Pass zone. Snow surfaces may be firm and icy first thing in the morning before the sun’s rays are able to soften them. On Thursday, cool east winds could delay this process compared to recent days. Slopes at lower elevations may not soften much at all if east winds are able to persist throughout the day. If you are in a wind-sheltered area and enough softening happens on slopes that see direct sunshine, there is potential for small Wet Loose avalanches to occur. Take a second to step off your mode of travel and see how deeply you are sinking into the snow. If you are sinking into wet snow past your ankle, start thinking about these avalanches. They may be more likely on steep slopes near rocky outcrops or cliffs where the snowpack is shallower. 

You may also find that larger isolated avalanches could occur if blocks of snow or ice are able to fall or cornices are able to collapse due to the sun’s influence. Multiple large Glide avalanches occurred last weekend as temperatures soared and liquid water made its way through the snowpack. We believe that most of that liquid water has since drained out the bottom of the snowpack. That doesn’t mean that it’s all gone, so take a look at the slopes above you for sagging cornices or large cracks in the snow and then limit your time spent below these unpredictable time bombs.

The extended diurnal spring cycle has left us with a firm surface crust with melt forms and smaller melt-freeze crusts below. We do not currently have any layers of concern deeper in the snowpack that we are tracking. 

As you travel, you may find variable surface conditions depending on aspect, elevation, or time of day. This includes sun softened snow, pockets of wind-deposited snow, breakable crust, or firm and icy surfaces. Be prepared for traveling over these variable surfaces by bringing the right equipment and choosing safe travel routes that protect you from slipping and falling into a terrain trap or for a long distance.