Valdez
Above 3,000ftModerate
1,500 to 3,000ftModerate
Below 1,500ftModerate
Degrees of Avalanche Danger
Avalanche Problems
Problem 1
Northeast wind ramped up to moderate-strong in our forecast area 2/9. sensitive wind slabs were observed on Thursday at upper elevations in wind channeled terrain and on the lee side of ridges. Stable conditions were observed in areas unaffected by wind.
It will be possible to trigger a wind slab avalanche 1-3 feet in depth in specific areas. Indicators of wind slab include, hard snow over soft and pillowed snow surfaces. Shooting cracks, collapsing or recent avalanche activity are all signs that unstable snow exists that is capable of producing avalanches.
Winds are forecasted to switch to southeast by the afternoon and become strong by later tonight as another storm approaches our area. This change in wind direction will be loading different aspects.
Likelihood:
- Almost Certain
- Very Likely
- Likely
- Possible
- Unlikely
Size:
- Historic
- Very Large
- Large
- Small
Trend
- Increasing
- Steady
- Decreasing
Problem 2
Below 2500′ 18-36″ of settled storm snow is sitting on the 1/25 rain crust. This rain crust has lost strength since it has formed and has created a weak layer. It will be possible for the 1/25 rain crust to act as a failure plane in steep terrain at low elevations.
Watching for signs of instability such as shooting cracks and digging snowpits are a good idea if choosing to travel in steep terrain at low elevations.
Likelihood:
- Almost Certain
- Very Likely
- Likely
- Possible
- Unlikely
Size:
- Historic
- Very Large
- Large
- Small
Trend
- Increasing
- Steady
- Decreasing
Problem 3
Weak snow continues to exist near the base of our snowpack in all three climate zones. This weak snow has recently been under increasing pressure as heavy snowfall and strong winds occurred 2/5-7. The last recorded avalanche activity at this layer occurred during the 1/23-25 storm on Nicks Buttress / ~3500’/ north aspect (see avalanche activity section). The amount of snow and wind our area just received was significant, and was a great strength test of weak snow near the base of our snowpack. No avalanches have been observed that failed or stepped down to this layer during the latest storm. Human triggered avalanches are currently unlikely to occur that fail on weak snow near the base of our snowpack.
Faceted snow near the ground has been found to vary significantly from place to place. In most locations this snow has been found to be rounding (gaining strength) and unreactive in stability tests. In thin areas of the snowpack these facets are significantly more developed. The most likely places to affect weak snow near the ground will be in areas where the snowpack is thin.
If you find it is possible to push a ski pole to the ground in areas you travel. Assume that a weak faceted snowpack exists in that location, that could act as a trigger point.
Depth hoar from Nicks Buttress ~4000′ North aspect 1/31.
Likelihood:
- Almost Certain
- Very Likely
- Likely
- Possible
- Unlikely
Size:
- Historic
- Very Large
- Large
- Small
Trend
- Increasing
- Steady
- Decreasing
Avalanche Activity
Below is a summary of observed Avalanche activity from the last 7 days. Avalanches that were noted earlier in the season can be viewed by clicking the link below.
If you trigger or observe an avalanche consider leaving a public observation.
2/7- DOT avalanche control work on 2/7 produced several D2-2.5 avalanches. All of these appear to have failed at the new snow/old interface without any step downs observed. Avalanche activity mostly occurred in the mid elevation band 3500′-4000′ on the Buttresses of RFS, Cracked Ice, and Python. The most significant results occurred on Berlin Wall at ~5000′ with a crown that looks to exceed 2 meters. This was likely due to significant wind loading during the storm.
Very little natural avalanche activity was observed.
2/9- Several small (D1) natural avalanches were observed that failed on steep wind loaded terrain.
Weather
Check out our updated weather tab! A collection of local weather stations are available for viewing with graphs and tabular data included.
NWS Watches and warnings
NONE NWS Point forecast for Thompson Pass
Date Friday 02/10/23 Saturday 02/11/23 Time (LT) 06 12 18 00 06 12 18 00 06 Cloud Cover SC OV OV OV OV OV OV OV OV Cloud Cover (%) 40 95 95 100 100 100 100 85 100 Temperature 3 10 16 18 21 25 25 21 17 Max/Min Temp 17 16 27 16 Wind Dir SE SE E SE SE SE SE SE NE Wind (mph) 6 13 24 16 13 14 13 6 5 Wind Gust (mph) 20 28 39 28 28 33 Precip Prob (%) 0 40 80 100 100 100 100 90 60 Precip Type S S S S S S S S 12 Hour QPF 0.09 0.30 0.35 0.13 12 Hour Snow 1.0 4.7 4.7 1.8 Snow Level (kft) 0.0 0.0 0.0 0.2 0.5 0.7 0.6 0.4 0.1
Click on link below for Thompson Pass weather history graph:
Date:
02/11 |
24 hr snow | HN24W* | High temp | Low temp | 72 hour SWE* | February snowfall | Seasonal snowfall | Snowpack Depth |
Valdez | 0 | 0 | 32 | 17 | .45 | 37 | 182 | 64 |
Thompson pass | 0 | 0 | N/O | N/O | N/O | 52 | 341 | 62 |
46 mile | 0 | 0 | 20 | -12 | N/O | 13 | ~80** | 48 |
*HN24W- 24 hour Snow water equivalent in inches
*SWE– Snow water equivalent
**46 mile seasonal snowfall total begins December 1st.
Additional Information
Click on the link below for a running summary of the seasons weather history.
Announcements
The avalanche hazard is moderate at all elevations. Human triggered avalanches are possible in recently wind loaded terrain 1-3 feet in depth. Hard snow over soft is an indication of wind loaded snow and shooting cracks are a bullseye sign that unstable snow exists.
Posted by Gareth Brown 02/10 6:30 am.
For a description of current avalanche problems, weather information, season history and more click the (+ full forecast) button. Avalanche forecasts will be issued Wednesday-Sunday.
If you have pictures of recent natural or human triggered avalanches or notice signs of instability such as shooting cracks or collapsing, leave an observation to help improve forecast accuracy.