The mountains are still shedding their snow as they transition to a springtime snowpack, and we continue to notice more natural avalanches. It is becoming increasingly difficult to track exactly when some of these avalanches are occurring, but here are a few that we know happened since the last advisory was posted on Tuesday morning:
Summit Lakes: A large natural wet slab avalanche occurred on Tuesday afternoon.
Tincan: We noticed a fresh glide avalanche on a south-facing slope below Tincan’s Common Bowl that occurred sometime between 12:30 and 2:00 p.m. yesterday afternoon.
|Signal Word||Size (D scale)||Simple Descriptor|
|Small||1||Unlikely to bury a person|
|Large||2||Can bury a person|
|Very Large||3||Can destroy a house|
|Historic||4 & 5||Can destroy part or all of a village|
The mountain snowpack is continuing its annual transition from a dry, wintertime regime to a wet springtime pack. We have seen a widespread natural cycle since temperatures first heated up last Friday, and more natural activity is expected in the heat of the day today. There are a few things to be aware of as we continue on this springtime shed cycle.
There are a few wildcards today that make it a little bit more difficult to anticipate the timing of when we will start to see wet snow avalanches this afternoon. Increasing cloud cover will limit the heat input from direct sun, but clouds may also act like panels on a greenhouse, trapping in radiation from the sun without allowing the snow surface to cool itself by radiating heat back out to the sky. Moderate winds will have a cooling effect on the snow surface, which may delay surface melting and the onset of natural avalanche activity this afternoon.
The key to safe travel will be paying attention to indications of poor stability. As soon as you start to notice snow surfaces becoming unsupportable, it is time to head back to the parking lot. If you are sinking up past your boot tops in wet, sloppy snow, or if you are starting to notice rollerballs rolling down slopes, you can bet that conditions are quickly becoming dangerous. Be sure to plan your day so you don’t need to traverse under steep slopes in the afternoon, when natural avalanche activity will be likely.
Cornices: Daytime heating is making cornices more tender, increasing the likelihood of cornice fall. As always, be sure to give them plenty of space when traveling along ridgelines, and limit the time spent traveling under them.
Glide cracks have been releasing for the past week. This includes some cracks that have been around for several weeks, and others that have only formed since temperatures warmed up last Friday. More glide activity is likely today. These can be large and destructive since they involve the entire season’s snowpack. Be sure to avoid spending time below glide cracks since they can release suddenly and unexpectedly.
Yesterday: Temperatures reached the low 40’s to low 50’s F under clear skies, with overnight low temperatures in the low 30’s F. Winds were out of the east at 5-20 mph.
Today: Cloud cover is expected to slowly increase during the day and into tonight, with scattered clouds in the afternoon and mostly cloudy skies tonight. Seward might even see light rain to 2500′. High temperatures are expected to be slightly cooler than yesterday, reaching the high 30’s to low 40’s F today and then dropping down to the low 20’s to low 30’s overnight. Easterly winds are expected at 10-20 mph near ridgetops.
Tomorrow: Skies are expected to clear up tomorrow morning, with sunny skies and high temperatures in the 40’s-50’s F in the afternoon. Cloudy skies overnight tonight mean we will see little to no re-freeze overnight. Winds are expected to be light at around 5 mph out of the east.
PRECIPITATION 24-hour data (6am – 6am)
|Temp Avg (F)||Snow (in)||Water (in)||Snow Depth (in)|
|Center Ridge (1880′)||42||0||0||99|
|Summit Lake (1400′)||43||0||0||35|
|Alyeska Mid (1700′)||43||0||0||111|
RIDGETOP 24-hour data (6am – 6am)
|Temp Avg (F)||Wind Dir||Wind Avg (mph)||Wind Gust (mph)|
|Seattle Ridge (2400′)||43||SE||9||13|
|05/18/21||Turnagain||Observation: Tincan Ridge||Joe Kurtak|
|04/30/21||Turnagain||Observation: Sunburst||W Wagner Forecaster|
|04/27/21||Turnagain||Observation: Tincan Ridge||Joe Kurtak|
|04/26/21||Turnagain||Observation: Magnum||Creighton/ Hoople|
|04/25/21||Turnagain||Observation: Sunburst||Nick D'Alessio|
|04/24/21||Turnagain||Observation: Airplane obs||Johnston-Bloom / DiJulia /Hilliard Forecaster|
|04/24/21||Turnagain||Observation: Corn biscuit||Heather Johnson|
|04/23/21||Turnagain||Avalanche: Lynx Ck Drainage||W Wagner Forecaster|
|04/23/21||Turnagain||Avalanche: Sunburst||Eeva Latosuo|
|04/23/21||Turnagain||Observation: Center Ridge Turnagain pass||Joe Kurtak|
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.