Following a two-week stretch of sunny skies and spring-like conditions we await a weather pattern shift. Several storms are on tap tomorrow and into the weekend. Winds will be the first thing to change today. Expect light Easterly winds to build to Moderate (10-25mph) by the late afternoon and 1-2” of new snow possible. Shallow wind slabs may form on leeward features, but we don’t expect the avalanche danger to rise until tomorrow with more snow. However, pay attention to changing conditions and if more snow falls anticipate thicker wind slabs.
The storm tomorrow could produce up to a foot of snow and more is on the way Saturday into Sunday. In anticipation of this weather shift, we have been closely mapping surface conditions. Surface hoar has been observed from valley bottoms to the Alpine and is resting on a variety of a sun crusts on Southerly facing slopes. On shaded aspects surface hoar and 4-8” or so of soft near surface facets sit over a firmer base. Along ridgelines and areas affected by the NW wind a few weeks ago, there is hard sastrugi, wind crusts and/or rime crust. This set-up does not bode well for future bonding and will be our next concerning layers once buried.
Things to keep in mind if you are headed into the backcountry today:
Surface hoar sits on a variety of surfaces: loose snow, firm sun crusts, and hard wind board. Our current surface conditions will become our next layer of concern with more snow tomorrow through the weekend.
Yesterday: Skies were partly cloudy. Temperatures were in the 20s F to low 30s. At lower elevations temps bumped into the mid-30s F during the day. Ridge tops winds were light from the West shifting to the East overnight. No precipitation fell.
Today: Expect overcast skies and winds to increase this afternoon. Ridge tops winds from the East will start out light 5-15mph and increase into the 20s mph by the afternoon. 1-2″ (0.12″ SWE) of new snow is possible today and 2-6″ new snow overnight. Temperatures in the upper elevations will be in the 20s F. Sea level temps will increase into the 30s F and rain/snow line may reach 500′.
Tomorrow: Snow showers are expected to increase tomorrow morning and into the afternoon with 4-8″ of new snow possible. Easterly ridge top wind will be in the 30s mph with gusts in the 40s mph. Temperatures will be in the 20s F in the upper elevations and 30s F near sea level. Expect snow to transition to rain at lower elevations.. A more powerful storm is expected Saturday into Sunday with another shot of snow accumulation, stronger winds and warmer temps.
|Temp Avg (F)||Snow (in)||Water (in)||Snow Depth (in)|
|Center Ridge (1880′)||30||0||0||57|
|Summit Lake (1400′)||28||0||0||27|
|Alyeska Mid (1700′)||31||0||0||52|
|Temp Avg (F)||Wind Dir||Wind Avg (mph)||Wind Gust (mph)|
|Sunburst (3812′)||22||W –> E||5||14|
|Seattle Ridge (2400′)||27||SW –> SE||3||9|