Avalanche Forecast
Issued: Apr 28th, 2017 4:00PM
The alpine rating is Loose Wet, Cornices and Deep Persistent Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeSaturday could be a great day for spring skiing! Cool temperatures are forecast which should provide good travel on crusts, with 20-30cm of soft snow on N aspects in the alpine. Start early enough to be back down by noon when things start heating up!
Summary
Weather Forecast
A weak ridge is moving in Friday night with forecasts for a good overnight freeze. Saturday should see drier and sunnier conditions with clouds and flurries beginning in the afternoon and 5-10cm of snow overnight into Sunday.
Snowpack Summary
Another 5-10 cm of new snow Thursday night with light winds. There are a variety of melt freeze crusts in the upper snow pack on all aspects and elevations except for due north above 2300 m. A basal weakness remains at the bottom of the snow pack. It is currently only reactive to large triggers like cornices but may wake up with solar warming.
Avalanche Summary
Minor sluffing out of steep cliffs and some pin wheeling on steep solar slopes on Friday.
Confidence
Problems
Loose Wet
Clearing skies and sunshine on Saturday morning will rapidly moisten the new snow on solar aspects increasing the likelihood of loose wet avalanches. Start early and be off steep solar aspects by mid-day as the temperature increases.
- If triggered the loose wet sluffs may step down to deeper layers resulting in large avalanches.
- Pay attention to sluffing off cliffs and steep solar terrain, signs of a warming snowpack.
Aspects: North, North East, East, South East.
Elevations: All elevations.
Likelihood
Expected Size
Cornices
Cornices continue to fail especially with daytime heating. Minimize your time underneath these and remember that a cornice failure could also trigger the deep persistent slab on the basal facets.
- Give cornices a wide berth when travelling on or below ridges.
- Cornices become weak with daytime heating, so travel early on exposed slopes.
Aspects: North, North East, East, South East.
Elevations: Alpine.
Likelihood
Expected Size
Deep Persistent Slabs
The weak basal facets can produce large avalanches with large triggers or heat. Remember that the snowpack is generally strongest when it is cool and stick to planar, supported slopes with a deeper snowpack when entering steep terrain.
- Pay attention to overhead hazards like cornices which could easily trigger the deep persistent slab.
Aspects: North, North East, East, South East.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Apr 29th, 2017 4:00PM