South Columbia

Winter and Summer are clashing in a pretty typical Spring fashion Monday. The day starts warm and then turns stormy with a healthy amount of wind expected. Be sure your travel plans account for a wide variety of changing conditions.

Moderate - Forecast snowfall amounts are uncertain on Monday

There is a lot of uncertainty in the current weather forecast as winter and summer battle it out in this season we call spring. In short, temperatures are expected to cool a bit Monday and Tuesday and the South Columbias should see significant precipitation before the ridge rebounds and sends the freezing level into the heavens once again. MONDAY: Freezing level beginning near 2500 m, lowering throughout the day to around 1500 m by sunset, 5 to 20 mm of precipitation expected, overcast sky, moderate winds first out of the southwest switching to northwest in the late afternoon. TUESDAY: Freezing level beginning near 1000 m rising to around 2000 m, scattered cloud cover in the AM, increasing to overcast in the afternoon, convective snow/rain showers possible, light to moderate west/southwest wind. WEDNESDAY: Freezing level starting around 1800 m, rising to over 2500 m throughout the day, no significant precipitation expected, strong to extreme west/northwest wind, sky steadily clearing throughout the day. For more detailed mountain weather information visit avalanche.ca/weather

It should come as no surprise that the very warm temperatures and strong sun have resulted in a lot of natural avalanche activity. Slab avalanches to size 2.5 have been very common over the last few days on almost all aspects, (the exception being high elevation north.) There has also been an immense amount of both loose wet avalanches and cornice failure occurring over the last few days which have been coming in all shapes and sizes from small to scary big. The odd glide release continues to be observed too.

The warm daytime temperatures and weak/non-existent overnight refreeze over the past few days have moistened the upper snowpack at all elevations. High elevation north may be the last hideout of relatively "cold" snow heading into Monday morning. Interestingly, there may also be some medium grain surface hoar remaining on these same high elevation north facing features. Below 1400 m, the snowpack is likely fully isothermal. The March 22nd rain crust is present to around 2000 m, but the warm temps have likely allowed the overlying 40 to 50 cm of snow to bond well. Once it freezes, March 22nd should not be much of a concern. The late February persistent weak layer is now down 60 to 120 cm below the surface. While it may be a concern in isolated terrain, it would probably take a large trigger like a cornice fall or surface avalanche in motion to provoke it.