South Columbia Avalanche Forecast
Apr 23rd, 2019 3:45PM
Lingering wind slabs may still be reactive to human triggers; especially on lee features below alpine ridgetops.
TUESDAY NIGHT: Mostly cloudy with isolated alpine flurries; 1-3 cm / Light, westerly winds / Alpine low -3 C / Freezing level 1500 m.
WEDNESDAY: Mix of sun and cloud / Light, northwesterly winds / Alpine high -1 C / Freezing level 1800 m.
THURSDAY: Sunny / Light, southwesterly winds / Alpine high 2 C / Freezing level 2100 m.
FRIDAY: Cloudy with isolated alpine flurries; 1-3 cm / Light, southwesterly winds / Alpine high -1 C / Freezing level 1800 m.
No new avalanches were reported in this region on Monday. However, there are currently very few professional observers submitting daily observations. Please submit your observations to the MIN. Photos of avalanches or current conditions are particularly useful.
On Saturday, numerous natural loose wet avalanches up to size 1.5 were reported on all aspects/elevations.
On Friday, Numerous loose wet and slab avalanches to size 2.5 on all aspects in the alpine were reported. Although not in this region, check out these two MINs from Saturday in Glacier National Park HERE. and HERE
20-30 mm. of rain has soaked the snowpack at treeline and below. The rain/snow boundary on Friday was around 2200 m. New snow amounts in the alpine will taper rapidly with elevation and likely equate to around 15-25 cm of moist snow at upper elevations adding to the 20-40 cm recent snow which overlies a crust everywhere except high elevation, north facing terrain where preserved surface hoar (weak, feathery crystals) may be present in isolated locations down 30-60 cm. A similar layer buried in early April is down 50-80 cm. Smaller storm slab avalanches may step down to one of these deeper weak layers.
Below treeline, snow is disappearing rapidly.
- Use small slopes without consequence to test the bond of the recent snow.
- Pay attention to changing conditions with elevation/aspect.
- Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
Aspects:North, North East, East, South East, North West.
Strong solar radiation may trigger loose wet avalanches on steep terrain; especially at upper elevations where there is new snow.
- A moist/wet snow surface, pinwheeling and natural avalanches all indicate a weakening snowpack.
- Avoid terrain traps such as cliffs and gullies that increase the consequence of small avalanches.
Aspects:North East, East, South East, South, South West, West, North West.
Valid until: Apr 24th, 2019 2:00PM