A strong Pacific storm is bringing warm temperatures, heavy precipitation and strong winds. Be aware of rapidly developing avalanche conditions when this storm arrives.
Weather Forecast
Light precipitation is forecast for today, and is going to be followed by a major storm this evening and for the next few days. This storm is being referred to as a "Pineapple Express" and is forecast to bring 20-25cm overnight, and another 20-30cm on Friday, with rising temperatures and freeze lines. Freezing levels are up to 1300m today.
Snowpack Summary
Top 40 cm settling storm snow with a soft breakable crust on top where it is exposed to the sun. Feb 12 surface hoar and crust layers down 50-60cm, fist to 1 finger snow over top. Mid pack is well settled.
Avalanche Summary
No new avalanches were observed in the park yesterday.
Confidence
Timing, track, or intensity of incoming weather system is uncertain
Problems
Persistent Slabs
Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.
Storm Slabs
Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.