Valdez
Above 3,000ftModerate
1,500 to 3,000ftModerate
Below 1,500ftLow
Degrees of Avalanche Danger
Avalanche Problems
Problem 1
The last week of weather that brought clear skies and mild temperatures has allowed for the upper snowpack to settle and gain strength. Our last snowfall occurred a week ago, and our last significant snowfall event was nearly 2 weeks ago. Light snowfall is forecasted today, we are not expecting to receive enough snow to elevate the hazard. The most recent stability concern has revolved around wind slabs that were formed on 3/25. These have since gained strength and currently have been reported and observed as unreactive in most locations. These wind slabs may remain reactive in small pockets of steep, and or rocky terrain where they overlie faceted snow.
The 3/25 north wind event has created a lot of spatial variability in regards to the amount and quality of the snow that fell mid March (3/17-22). In the majority of locations, this snow is wind affected and sits atop very hard wind damaged surfaces created in the the late feb- early march drought/ wind events. The Hamilton storm (3/17) has settled to 1-2 feet in depth with good bonding continuing to be observed and reported at the 3/17 interface. Clean shears have been identified within the Hamilton storm snow although propagation in snow pits has not been observed and sensitivity is low.
Human triggered avalanches remain a possibility on steep isolated terrain features up to one foot in depth. Even though good stability is currently present continued snowpack assessment is encouraged while traveling in steep and/ or consequential terrain. Remember that even small avalanches can have serious consequences in steep or exposed terrain.
Likelihood:
- Almost Certain
- Very Likely
- Likely
- Possible
- Unlikely
Size:
- Historic
- Very Large
- Large
- Small
Trend
- Increasing
- Steady
- Decreasing
Problem 2
Weak snow exists at the base of our snowpack. This weak snow is currently unlikely to be affected due to the strength of old wind affected snow at the 3/17 new/old interface. Depth hoar may become a concern later in the season if our area returns to a period of major snowfall and the very strong wind damaged layer at the new/old interface starts to break down and lose strength within the snowpack. As very hard wind slabs break down within the snowpack a person or machines weight will have a more direct affect on weak layers at the bottom of the snowpack. In addition, the increasing intensity of the sun will be putting pressure on deep layers during the heat of the day.
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.
3/24- Ski cuts were reported as being productive, with avalanches up to D2 at the 3/21 interface.
3/18-21- Several D1-D2 human triggered avalanches have been reported. For the most part these have been outside our forecast zone and appear to be more likely in areas with either a weaker underlying snowpack (continental zone) or where storm totals were higher (SE of Thompson Pass). Remote triggers have also been reported as the Hamilton storm slab has settled and gained cohesion.
3/17- Multiple D1-D2 natural storm slab avalanches were reported and observed along the road corridor. These all failed within the storm snow with the exception of one deep persistent avalanche reported on Billy Mitchell.
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, warnings and advisories
NONE
NWS Point forecast for Thompson Pass
Date Thursday 03/30/23 Friday 03/31/23 Time (LT) 04 10 16 22 04 10 16 22 04 Cloud Cover OV OV OV OV OV OV OV OV OV Cloud Cover (%) 100 90 90 90 90 85 85 80 90 Temperature 21 23 28 25 21 23 29 25 20 Max/Min Temp 28 21 29 18 Wind Dir E E NE NE NE NE NE NE N Wind (mph) 6 6 5 5 10 11 5 8 11 Wind Gust (mph) 23 27 29 29 27 29 32 Precip Prob (%) 80 80 80 60 30 20 40 20 10 Precip Type S S S S S S S S S 12 Hour QPF 0.08 0.04 0.04 0.03 12 Hour Snow 1.1 0.3 0.0 0.0 Snow Level (kft) 0.0 0.1 0.4 0.1 0.0 0.0 0.3 0.0 0.0
Click on link below for Thompson Pass weather history graph:
Date:
03/30 |
24 hr snow | HN24W* | High temp | Low temp | 72 hour SWE* | March snowfall | Seasonal snowfall | Snowpack Depth |
Valdez | 0 | 0 | 40 | 26 | 0 | 17 | 235 | 51 |
Thompson Pass | 0 | 0 | 26 | 18 | 0 | 58 | 426 | N/O |
46 mile | 0 | 0 | 36 | 10 | 0 | 33 | ~115** | ~60 |
*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 remain possible up to 1 foot in depth in isolated areas. Keep in mind that even small avalanches can be dangerous in exposed and/or consequential terrain.
Posted by Gareth Brown 03/30 8:00 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.