Spring Time Avalanche Concerns
Loose Wet Avalanches are the most common springtime avalanche hazard as a strong sun and warm temps melt and soften the snow surface. Signs of instability include rollerballs, pinwheels, and "point release" sluffs that fan out and gather more snow as they travel down the slope. Timing is everything this time of year. Work slopes according to their aspect in relation to the sun and get off of steep slopes as they become wet and sloppy.
Wet Slabs release when melt water saturates a layer in the snowpack and the over riding slab fails as a cohesive layer. These avalanches are harder to predict than loose wet, and outward signs of this problem are not obvious, but sloppy, wet, or punchy snow indicate that the pack is trending towards unstable. Successive nights without a freeze and warm daytime temps contribute to instability. Avoid thin shallow rocky areas and terrain under cliffs, especially if the snow is becoming wet and sloppy.
New Snow can cause the avalanche danger to rise just like in the winter. Poorly bonded new snow can cause problems on all aspects when there is more than about 6" of new snow. Loose snow sluffs and soft slab avalanches are possible. This type of instability typically settles out in a day or two.
Wind Drifted Snow can create unstable drifts or slabs on the leeward sides of ridge crests and terrain features. Recent wind drifts are recognizable by their smooth, rounded appearance and cracking is a sign of instability. Unstable wind drifts can linger for days or even up to a week.
Persistent Weak Layers can occasionally linger well into spring and deep and dangerous avalanches remain possible. Weak, faceted snow tends to hang around on northerly aspects and in shallower snowpack areas around cliffs and rock outcroppings. Avoiding likely trigger points such as thin slope margins or steep convexities are ways to minimize your risk for this low probability but high consequence hazard.
