Wind will impacted any loose snow, pay attention to avalanche conditions that change with aspect and elevation.
Strong to extreme winds have redistributed fresh snow. More reactive deposits will be found on convex rolls and leeward terrain. The new and recent snow may overlie a weak interface which could result in deeper and touchier than expected slabs.
A persistent slab problem formed by a crust down 80-150 cm has created a low likelihood, high consequence scenario that is difficult to forecast. Avoid likely trigger spots such as steep, rocky slopes with a shallow or thin to thick snowpack.
Saturday night: Cloudy with isolated flurries, up to 5 cm. Strong to extreme SW to NW ridgetop wind. Treeline low around -16 °C and rising.
Sunday: Mostly sunny. Moderate to strong SW to NW wind. Increasing temperatures with a treeline high around -2 °C. Sun, daytime warming, and possible inversion will push temperatures to 0 °C this evening for elevations above 2000 m.
Monday: Sunny. Moderate SW wind. Treeline high around -1 °C.
Tuesday: Incoming flurries, 5 cm. Moderate WSW wind. Treeline high around -1 °C.
On Friday, explosives and skiers easily triggered storm slab avalanches to size 1.5.
On Wednesday, explosive control work produced numerous loose dry and thin wind slab avalanches in alpine terrain. These avalanches started small but entrained mass in tracks, growing to size 2.5 and running up to 1300m. It is worthy to note that no deep slabs were triggered.
On Monday and Tuesday, natural, explosive and skier triggered storm slabs and loose dry avalanches size 1-2 were observed out of NE-SE aspects in the alpine.
The persistent slab problem has produced sporadic and spotty activity in the South Rockies and nearby regions. The most recent avalanche in the region was Dec 31, when explosives triggered a size 2.5 wind slab avalanche that stepped down to the persistent slab layer on a SE aspect near treeline. Otherwise, persistent slab activity has not been observed in the region since before Christmas. A few recent notables from surrounding regions feature in our latest blog, Photos of recent persistent slab avalanches in the southern interior.
Another 10 cm arriving Saturday morning brough last weeks storm totals 30-60 cm. Strong southwest to southeast winds have developed more reactive deposits around convex and lee features. This recent snow covered a hard, faceted snow surface which formed during cold temperatures, and may take a little time to bond. Sun and warm temperatures on Sunday may turn steep solar aspects moist in the afternoon and encourage loose, wet avalanches.
The most notable layer of concern in the snowpack is a crust that was formed in early December and is now typically down 80-150 cm. The most recent avalanche on this layer was a week ago but sporadic activity has been observed in neighboring regions in the past week. This layer has created a tricky low likelihood, high consequence scenario which is best managed through conservative terrain choices and disciplined backcountry travel techniques.
