Hatcher Pass
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The Bottom Line
The avalanche danger is CONSIDERABLE above 3500′ for WIND SLABS. The danger is MODERATE below 3500′. Human triggered avalanches will be likely. Natural avalanches will be unlikely.
The duration and intensity of the Easter Storm has added new wind and storm slab instabilities that will linger for another 24-48 hours.
Carefully assess and evaluate the snowpack and utilize cautious route-finding and terrain management techniques.
| Tue, April 2nd, 2024 |
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| Travel Advice | Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features. | Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern. | Dangerous avalanche conditions. Careful snowpack evaluation, cautious route-finding, and conservative decision-making essential. | Very dangerous avalanche conditions. Travel in avalanche terrain not recommended. | Extraordinarily dangerous avalanche conditions. Avoid all avalanche terrain. |
| Likelihood of Avalanches | Natural and human-triggered avalanches unlikely. | Natural avalanches unlikely; human-triggered avalanches possible. | Natural avalanches possible; human-triggered avalanches likely. | Natural avalanches likely; human-triggered avalanches very likely. | Natural and human-triggered avalanches certain. |
| Avalanche Size and Distribution | Small avalanches in isolated areas or extreme terrain. | Small avalanches in specific areas; or large avalanches in isolated areas. | Small avalanches in many areas; or large avalanches in specific areas; or very large avalanches in isolated areas. | Large avalanches in many areas; or very large avalanches in specific areas. | Very large avalanches in many areas. |
No recent avalanches were observed yesterday due to stormy weather and poor visibility. We expect that many small and a few large natural avalanches occurred during the storm on Sunday.
The forecasting area received upwards of 23” of new storm snow since 1200 on 3/30. Moderate gusting strong winds predominantly out of the ESE and SE with large quantities of new snow for transport have loaded lee slopes. Winds were stronger at Frostbite, Hatch and Marmot weather stations than Independence Mine. Prevailing 48 hour winds at Marmot @ 4500′ were ESE to SE 27 gusting 31-47mph for 9 hours and Hatch @ 4561′ ESE shifting SE at 32-41mph gusting 40-62mph for 16 hours.
| 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 |
Small to large wind slabs will be likely to human trigger today on west to northeast (clockwise) aspects at upper elevation on slopes steeper than 30º. It will be possible to human trigger wind slabs at mid and low elevation. Natural avalanches are unlikely.
Strong sustained winds over the past 48 hours tapered overnight and winds are reporting ESE gusting 26-30 mph at 4500′ this morning. While the main loading event is over, moderate winds will be capable of transporting up to 20″+ of new snow from yesterday’s storm. Wind slabs that formed during the storm are likely to fail 1-2′ deep on lingering facets or in isolated terrain with uniform and firm supportive crusts.
Winds are forecasted to diminish throughout the day. Expect this problem to trend from reactive to subborn over the next 24-48 hours.
Winds remained steady throughout the day yesterday. At 0500 this morning, they were moderate gusting strong+ at Hatch Peak.
Winds are forecasted to diminish from moderate gusting strong. With plenty of new snow available for transport, even sustained moderate winds could add additional load on lee aspects in specific terrain.
Use hand pits and pole probes to identify wind slabs. Look for hard snow sitting over weaker snow, smooth and rounded or lens shaped features. Shooting cracks or whumping are signs of instability and indicators of this avalanche problem.
| 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 |
Storm slabs 8-16″ thick will be possible to human trigger at all elevations, on all aspects, on slopes steeper than 30º. Natural avalanches are unlikely.
Storm totals vary considerably from yesterday’s storm with 8″ reported at 2700′ to upwards of 23″ of new snow at 3550′. A mostly right-side up storm (started warm and trended cooler) combined with cooler temperatures this morning will assist storm slabs in rapidly healing over the next 24-48 hours.
48 Hour accumulation at Independence Mine SNOTEL. 23″ of new snow since 3/30.
Over 23″ in 48 hours was recorded at the Independence Mine SNOTEL. The Marmot snow stake has finally surpassed the 5 ft mark!
To identify this avalanche problem use formal stability tests and hand pits to see if the new snow is behaving like a slab. Shooting cracks and whumping will be a red flag for this avalanche problem.
DRY LOOSE
Up to 20″+ of new snow from yesterday’s storm will make it possible to human trigger a small to large sluff in terrain 40º and steeper in protected terrain not affected by yesterday’s wind. It will be possible to either trigger a sluff that propagates a small slab avalanche or vice versa.
Expect new low density storm snow to be sitting on buried near surface facets which will increase the likelihood and speed of any sluff. In locations with previously firm surfaces, these will be easier to trigger and larger in volume. Sluffs may be able to sweep you off your feet into or over other rocks and hazards. Getting caught in steep terrain that funnels into any terrain trap has the potential to increase the size, risk and consequence of an avalanche. Small dry loose avalanches can be mitigated safely with appropriate slope cutting techniques.
The projected snow totals for today (4/1) have tapered from 6-8″ to 2-3″
NWS AVG Forecast here.
NWS point forecast here.
Marmot Weather Station here.
Independence Mine Snotel here.
Frostbite Bottom Snotel here.
State Parks Snow Report and Motorized Access information here.
XC trail grooming report for Mat-Su, Anchorage, and Kenai here.
