Haines Avalanche Center
Above 2,500ftConsiderable
1,500 to 2,500ftConsiderable
Below 1,500ftModerate
Degrees of Avalanche Danger
Avalanche Problems
Problem 1
Aspect: All aspects and below terrain features
Elevation: Mainly Treeline and above
New snow this week was about 6-14″ with strong SE winds Wednesday night! The wind calmed down and changed from SE-E to N-NW on Thursday. And intensified Friday with northerly outflow.
- The bottom line is that sensitive surface wind slabs from moderate NW winds will be most likely for human trigger. Older, more stubborn wind slabs from strong SE winds on Wednesday will be possible, but more difficult to trigger. This reverse loading event makes route finding through safe terrain in the alpine tricky.
- Look for active wind loading and fresh wind slab, cross-loading and top-loading.
- Remember that even small slopes with big consequences, like terrain traps, can be hazardous.
Identify wind-drifted snow by looking for stiff or hollow surface snow, and looking for cracking, whumphing, natural avalanches, and or active wind loading – treat these areas as highly suspect. Probe for strong over weak layering, the recipe for an avalanche. You can find safer conditions in wind-protected areas with softer snow.
Below 2,000ft warmer temps Nov. 25th caused a crust to form that has been observed in test pits. It has been buried by snowfall and wind loading over the past week. Cold temperatures will weaken this buried crust.
Likelihood:
- Almost Certain
- Very Likely
- Likely
- Possible
- Unlikely
Size:
- Historic
- Very Large
- Large
- Small
Trend
- Increasing
- Steady
- Decreasing
Problem 2
Confidence: Low-Moderate
Elevation: Between 2,500ft to 4,000ft
Look and listen for deep whumping! Report any natural avalanche activity on this layer!
One or more rain crusts from mid-October are now near the bottom of the snowpack in all zones. Weak snow above and below a crust may cause strong stubborn snow above it to fail and produce sizeable avalanche that could bury, injure or kill. Keep in mind a lot of new snow has fallen in the last 2 weeks adding stress to this layer. It will be possible to trigger an avalanche on this layer, 1 meter or deeper. We expect this October rain crust will be a lasting problem, so keep your guard up! This layer exists on all aspects, but observations are limited and uncertainty is high.
- What is the best way to manage this risk? We can simply avoid alpine terrain that is about 30 degrees and steeper. Be aware that venturing on these steeper alpine slopes is relatively high risk currently. Persistent slabs require a wide safety buffer.
- Another way to reduce your exposure to these deep weak layers would be to stick to areas of deeper snowpack (>1m deep). But be wary of hidden rocks that can act as trigger points, and thin areas around the margins of a slab.
Likelihood:
- Almost Certain
- Very Likely
- Likely
- Possible
- Unlikely
Size:
- Historic
- Very Large
- Large
- Small
Trend
- Increasing
- Steady
- Decreasing
Avalanche Activity
A large natural avalanche was reported on a west aspect near 3920 in the Lutak Zone that is visible from the highway. More information will be provided as it is received. See Persistent Slab problem.
Weather
Last week temperatures hovered near freezing in the mountains, with winds from the SE. Snowfall this week was around 6-14″. Winds switched from SE to NW and increased into typical northerly outflow as temperature plummeted into the single digits. Friday nights cold temperatures and clear skies could produce surface hoar formation in protected/sheltered areas, especially below treeline. Keep an eye out and submit an observation!
October brought heavy snow in the alpine, followed by a few rain/sun crusts. November has brought regular heavy snowfalls, adding up to 70+ inches so far. Winds have alternated between NW and SE.
Snow Depth [in] | Last 24-hr Snow/SWE [in] | Last 3-days Snow/SWE [in] | Today’s Freezing Level [ft] | Today’s Winds | Next 24-hr Snow/SWE | |
Mount Ripinsky @ treeline ** | 67″ * | 1″ / 0.05* | 3″ / 0.60* | 0′ | Mod, NW | 0″ / 0.00* |
Flower Mountain @ treeline | 47″ | 1″ / 0.05 | 5″ / 0.50 | 0′ | Mod, NW | 0″ / 0.00* |
Chilkat Pass @ 3,100ft | 26.5″ | 1″ / 0.05 | 3″ / 0.15 | 0′ | Mod, NW | 0″ / 0.00* |
( *star means meteorological estimate )
** The Ripinsky weather station is currently down, we will try to get it working again soon
Additional Information
Beware of deep treewells which can trap a person. It’s deep out there. Temperatures and will chill are cold. Be prepared to prevent hypothermia.
Become a sustaining Haines Avalanche Center Member by clicking the poster or visiting dev.alaskasnow.org/joinHAC. Support local forecasts, observations, education and weather stations. Join a community of winter recreationalists. Benefit from collective knowledge and skills. Help keep your friends and family safe in the backcountry. Get a free limited edition mountain buff, or neck gaiter with a $50 membership (first 20 members!).
Practice like you play. Make sure all your rescue gear is fully functional and your beacon has NEW batteries. Make sure 1) everyone in the group has a functioning beacon, shovel and probe 2) knows how to use them and 3) has trained in companion rescue in the last year. Keep your skills fresh. If you head into the hills, watch out for red flag avalanche conditions, natural avalanches, whoomphing or collapsing, and shooting cracks.
Education Video Links:
- AIARE
- How to Practice Avalanche Rescue Snowmobile Edition: https://youtu.be/2ML499MMDfM
- AK Sled Shed Motorized Learning:
- Intro: https://youtu.be/aoagKHfGkxs
- Personal Electronics in Avalanche Terrain: https://youtu.be/2Vz9S0OEyFk
- Snowmobile Macgyver Tool Kit: https://youtu.be/4WBNu_t6Bbk
- Head and Face Protection: https://youtu.be/jIzW89wOyZI
- Pre-season prep: https://youtu.be/zJmrb8cZlR4
- My Transceiver: https://youtu.be/yblaDWP7Jf8
- BCA Avalanche Safety for Snowmobilers
- How to Fix Common Snowmobile Problems in the Field: https://youtu.be/g9fiTxEvuFk
- Sleducation: Avalanche Safety for Snowmobilers: https://youtu.be/EWFOd_9DYb8
- Intro to Avalanche Transceivers for Snowmobilers: https://youtu.be/6ZLSBmsceog
- Avalanche Transceiver Trailhead Test for Snowmobilers: https://youtu.be/rWoXbadFBsY
- Avalanche Transceiver Searching Use Snowmobiles: https://youtu.be/w1ucyI6LMXM
- BCA Avalanche Rescue Series
- Beacon Search 101: https://youtu.be/nnHXLVA2FcE
- Avalanche Probing 101: https://youtu.be/-0_yDN5Drzw
- Avalanche Shoveling 101: https://youtu.be/dGQg9o3vAkM
- Organizing a Backcountry Rescue: https://youtu.be/gywtmukgt8s
- Post Avalanche Patient Care: https://youtu.be/9FyIeUy4wpQ
- Backcountry Evacuation: https://youtu.be/WPF-dciefL8
- Complex Multiple Burials Backup Techniques: https://youtu.be/pB6AfY2KyYo
- National Avalanche Center
- Avalanche Problems Explained: https://youtu.be/DkbnT_9-cHU
- Intro to North American Avalanche Danger Scale: https://youtu.be/r_-KpOu7tbA
Announcements
Thursday, Friday, Saturday and Sunday forecasts have begun. Click the –Full Forecast– button below for more details. We need your observations!