Weather models suggest that parts of the advisory will see a rise in wind from the northwest today with moderate speed, 15-20mph. Continued cold temperatures have kept Monday’s 10″ of dry snow very loose, which can easily be blown around by these winds, creating wind slabs in the lee of ridges and gullies. Winds slabs may form rapidly. Where these conditions align, it’s possible for a human to trigger a wind slab.
Remain alert for signs of wind slab formation: watch for active wind loading, firmer surface conditions, cracking or drum-like sounds in the snow, sometimes texture that appears rippled or wavy, and pillow-like features on the leeward side of wind exposed terrain. And as always, if you see cracking in the snowpack or hear whumpfing sensations, it’s time to reassess your plan.
Persistent Slab: Although unlikely, a loose dry avalanche or wind slab avalanche could step down and pull out a deeper slab. This is most suspect in Alpine elevation steep terrain.
Thick valley fog was over Turnagain Pass yesterday that extended from around 2,000′ to 3,000′. This photo was taken on Seattle Ridge and looking west toward Big Chief. 1.22.20.
Although the models predict wind, many areas have stayed calm since Mondays storm where 10″ of snow sits atop a 8″-12″ layer of loose facets. We’ve not seen or heard reports of Mondays storm gaining any slab character, but it is settling over time. As temperatures remain cold, the character of the recent surface snow is unlikely to create a slab unless it becomes wind effected. Prior to Mondays storm, it remained easy for a rider in steep terrain to trigger sluff of loose facets. Now, a relatively dry 10″ of snow adds to the volume of loose snow. Triggering this loose snow is predictable and may be managed with forethought. With that said, 20″ of loose snow could rapidly gain volume and momentum taking a rider through the fall line.
Seattle Ridge weather station – relatively calm winds before and since the 1/20 storm
Cornices and Glide Cracks: As always, limit exposure under glide cracks and give cornices a wide margin.
Yesterday: Thick valley fog remained in the 2000′-3000′ range for most of the day. Temperatures were in the single digits above 3,500′. At the lower elevations, temperatures remained in the teens trending into the single digits. Ridgetop winds were calm to light.
Today: Mostly sunny skies with a high near 7°F, with a low around -5°F. No chance of precipitation today. Winds will be out of the northwest from 15 to 20 mph and taper to light this evening.
Tomorrow: Mostly sunny trending to cloudy into afternoon and evening with a high near 1°F and a low around -5°F. Light to calm winds around 5 mph. No precip.
PRECIPITATION 24-hour data (6am – 6am)
|Temp Avg (F)||Snow (in)||Water (in)||Snow Depth (in)|
|Center Ridge (1880′)||9||0||0||44|
|Summit Lake (1400′)||8||0||0||16|
|Alyeska Mid (1700′)||11||0||0||46|
RIDGETOP 24-hour data (6am – 6am)
|Temp Avg (F)||Wind Dir||Wind Avg (mph)||Wind Gust (mph)|
|Seattle Ridge (2400′)||5||NNE||2||6|
|01/22/20||Turnagain||Observation: Sunburst||Adrian Beebee|
|01/22/20||Turnagain||Observation: Sunburst||Ryan Van Luit Forecaster|
|01/22/20||Turnagain||Observation: Seattle Ridge||W Wagner Forecaster|
|01/22/20||Turnagain||Observation: Tincan||Allen Dahl|
|01/21/20||Turnagain||Observation: Tincan||Eric Roberts|
|01/20/20||Turnagain||Observation: Eddies||H. Thamm B. Edwards|
|01/20/20||Turnagain||Observation: Eddies||Andy Moderow|
|01/19/20||Turnagain||Avalanche: south facing aspect on 3800ft bump just northeast of 4940||Anonymous|
|01/19/20||Turnagain||Avalanche: Cornbiscuit & Magnum||Allen Dahl|
|01/19/20||Turnagain||Observation: Eddie’s||Kakiko Ramos-Leon|
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.