A slow and steady spring time shed cycle persists. This is where above freezing temperatures cause the snowpack to loose its strength and becomes wet and saturated releasing naturally or with the weight of a person/snowmachine. The last two nights we’ve seen temperatures dip below freezing again in the upper elevations – causing a crust to form. Unfortunately this re-freeze is superficial and clouds have kept some heat in and mid elevations temps are still above freezing. Today and tomorrow it will be important to monitor this crust and pay attention to how much the sun and/or rain showers break it down. This is the time of year when avalanches from above can catch you by surprise. Solar aspects in the afternoon and evening are most vulnerable. Be aware that steep rocky areas with thin snow coverage heat up fast and natural activity will be more likely in these areas – including slopes that have already seen lots of avalanche activity. For Friday: If skies remain cloudy overnight and temperatures remain above freezing in the alpine a surface crust on Northern aspects may start to melt, making wet avalanches possible on all aspects.
WET SLAB, WET LOOSE and CORNICE FALLS:
Things to keep in mind if you are headed out:
Similar to the wet issues above, glide avalanches are also occurring with the springtime melt-down. Glide cracks are opening up and releasing on many slopes in the region – steer clear of any slopes harboring glide cracks. Check out the photo below from the motorized up-track. This slope is notorious for producing glide avalanches. Additional glide avalanche activity is expected today and through the week.
There are several buried persistent weak layers in the snowpack; ranging from buried surface hoar 2-6′ deep, mid-pack facets and facets near the ground. Shallow snowpack zones such as the Summit Lake area harbor depth hoar near the ground. On upper elevation North, West and Easterly aspects these weak layers could re-activate if the surface crust starts to melt and become wet on these aspects. If this melting occurrs triggering a larger natural slab avalanche may be possible.
Yesterday skies were partly clouding with scattered rain showers. Northerly ridgetop winds were light. Day time temperatures reached a high of 55F in the mid elevations and 40F in the upper elevations. Late in the evening widespread thin cloud cover was observed across the forecast zone. Overnight temperatures reached a low of 29F in the upper elevations and 35F in the mid elevations.
Today scattered rain showers will persist and patches of sunny skies are possible. Only a trace of precip (0.05″) is expected today and up to 0.15″ overnight. Daily temperatures are expected to reach the mid 50Fs in the afternoon and 40F in the upper elevations. Overnight lows are expected to remain above freezing (mid 30F’s) in the mid elevations reach just below freezing (30F) in the alpine. Winds are expected to remain light from the North.
A very similar weather pattern is expected Friday and into the weekend. Scattered rain showers and partly cloudy skies are expected vary accross the forecast region. Easterly ridge top winds may increase Friday night into Saturday, 15-20mph.
|Temp Avg (F)||Snow (in)||Water (in)||Snow Depth (in)|
|Center Ridge (1880′)||45||0||0||54|
|Summit Lake (1400′)||41||0||0||13|
|Alyeska Mid (1700′)||41||0||.03||50|
|Temp Avg (F)||Wind Dir||Wind Avg (mph)||Wind Gust (mph)|
|Seattle Ridge (2400′)||n/a||E||3||10|
|04/19/21||Turnagain||Avalanche: Triangle, Seattle creek||Will Morrison|
|04/18/21||Turnagain||Avalanche: Turnagain Pass Road Obs||Andy Moderow|
|04/18/21||Turnagain||Observation: Seattle Ridge, approximately 300 yards south of the up track||Brent Byrne|
|04/17/21||Turnagain||Avalanche: Road obs||Johnston-Bloom / Moderow Forecaster|
|04/16/21||Turnagain||Avalanche: Seattle Ridge||Wendy Wagner Forecaster|
|04/16/21||Turnagain||Avalanche: Turnagain Pass, non-motorized side seen from Seattle Ridge||CNFAIC Staff Forecaster|
|04/16/21||Turnagain||Observation: Sunburst||Lance breeding|
|04/15/21||Turnagain||Observation: Tincan||Schauer/ Rothman Forecaster|
|04/13/21||Turnagain||Observation: Turnagain Pass Road Obs||A Schauer Forecaster|
|04/12/21||Turnagain||Observation: Tincan||Johnston-Bloom / Latosuo Forecaster|
Status of riding areas across the Chugach NF is managed by the Glacier and Seward Ranger Districts, not avalanche center staff. Riding area information is posted as a public service to our users and updated based on snow depth and snow density to prevent resource damage at trailhead locations. Riding area questions contact: firstname.lastname@example.org
|Area||Status||Weather & Riding Conditions|
This is a general backcountry avalanche advisory issued for Turnagain Arm with Turnagain Pass as the core advisory area. This advisory does not apply to highways, railroads or operating ski areas.