Avalanche Forecast
Issued: Apr 23rd, 2023 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs and Loose Wet.
bchristie,
Avalanche Canada
❆ Winter just won't quit on the South Coast! ❆
Start on small slopes, and watch how the new snow is bonding to the old surface.
Unseasonable weather calls for cautious and adaptable terrain selection.
Summary
Confidence
Low
Avalanche Summary
A natural avalanche cycle may occur overnight, as the most rapid loading will be happening before midnight.
On Saturday, just north of Vancouver, small (up to size 1), rider triggered avalanches were reported.
Last week, storm snow was generally reactive to human traffic as seen in this Mountain Information Network post from the SkyPilot area, and this one from the Brohm ridge area. Both of these avalanches occurred on Thursday.
We expect that similar avalanches could be triggered by riders on Monday within the new storm snow.
Avoiding cornice exposure is also a good idea, as they are very large and looming at this time of year.
Snowpack Summary
Another wintery storm has likely dropped 5-15 cm of snow, even below treeline. Continuing moderate southwest wind could be forming deeper and touchier deposits in leeward terrain.
This new snow covers a surface that was thoroughly soaked by 25-40 mm of rain to mountaintops in most of the forecast area.
The exception is in the high alpine, where this new snow is falling on dry snow that was redistributed by moderate southwest wind.
The remainder of the snowpack is strong and well-bonded.
Cornices are large and looming at this time of year.
Weather Summary
If you are wondering why the freezing line and the snow line might be so different on some days, click here for more information:)
Sunday Night
Cloudy. Moderate to heavy rain/snow, 15-20 mm, with isolated areas on the immediate coast mountains around Vancouver of 25mm or more. Freezing level staying around 1200 m, but the snow line may drop as low as 700 m. Treeline low around -2°C. Moderate southwest ridgetop wind becoming light by the morning.
Monday
Low cloud. Trace of rain/snow expected. Freezing level around 1400 m. Treeline high around -2°C. Light west ridgetop wind.
Tuesday
Mostly cloudy. Light snow/rain. Freezing level rising from 1250 m to 1750 m. Light to moderate west or northwest ridgetop wind.
Wednesday
Partly cloudy. Light snow/rain. Freezing level rising to 2800 m. Moderate to strong west or northwest ridgetop wind.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Continue to make conservative terrain choices while the storm snow settles and stabilizes.
- Avoid terrain traps such as gullies and cliffs where the consequence of any avalanche could be serious.
- Avoid all avalanche terrain during periods of heavy loading from new snow, wind, or rain.
- Pay attention to cornices and give them a wide berth when traveling on or below ridges.
Problems
Storm Slabs
10 to 20 cm of new snow has likely fallen by Monday morning, possibly even below treeline. Use caution entering steep terrain features, around ridgecrests, and on convex slopes. Retreat to mellower terrain if you find signs of instability like shooting cracks, or recent avalanches.
Constantly observe the snow conditions where you are. The new snow may settle and bond quickly, but this repeated alternation between winter-like and spring-like conditions increases our uncertainty about how the new snow will behave.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Loose Wet
Reports of wet loose avalanches have continued through the recent stormy period. While the vast majority of these avalanches have been small (size 1), remember that wet loose avalanches are more dense, and harder to fight against. If you trigger a small avalanche in the wrong terrain, it can still have serious consequences.
Wet loose avalanches may be less likely at low elevations, where most of the snowpack has already experienced several heavy rainfalls and significant warming, but if you are finding, deep, slushy, loose snow, use extra caution on steep slopes.
Aspects: All aspects.
Elevations: Treeline, Below Treeline.
Likelihood
Expected Size
Valid until: Apr 24th, 2023 4:00PM
