Cariboos

Fair - Timing or intensity of solar radiation is uncertain

Another Pacific frontal system is expected to hit the coastal areas Thursday into Friday. This will generally affect the Interior on Friday. The upper flow will become Southwesterly and a ridge should develop for the weekend, bringing dryer conditions. Wednesday: Mix of sun and cloud, convective light accumulations through the day. Ridgetop winds light from the SW. Freezing levels near valley bottom, rising to 1700 m. Thursday: Mainly dry conditions with afternoon sunny periods. Moderate precipitation Thursday night into Friday am. Ridgetop winds light-moderate from the SW. Freezing levels rising to 2000 m in the afternoon. Friday: Light precipitation. Ridgetop winds moderate from the West. Freezing levels near 1400 m.

Recent avalanche observations include a couple of skier triggered ( controlled) size 1.5 loose wet avalanches from East aspects. Spring conditions exist in the region. Exposure to the sun, warm temperatures, and periods of rain are the most likely factors to influence the avalanche danger. If the temperatures go below freezing overnight, strong crusts should develop that are likely to hold the snowpack together. If the sun shines for a few hours, the crusts may break down quickly and moist surface snow avalanches may start running naturally. Continued warming from more sun, rain, or no overnight freeze, may cause surface avalanches to step down and trigger deeper wet slab avalanches. Prolonged warming may cause very deep releases on weak layers that were deposited early in the season, or on depth hoar that developed during the winter. It is important to monitor the temperature and the freezing levels as they may change rapidly from day to day, and as you travel through different elevations.

Last week, very warm temperatures affected all but the highest north facing slopes. Since Thursday morning, mostly light to locally moderate amounts of new snow have fallen forming soft slabs on the resulting crust while rain has continued to penetrate and weaken the snowpack at lower elevations. Up to 80cm below the surface, you will find another crust in the alpine and at treeline that may have been reactive with warming throughout last week. The mid-February buried surface hoar layer is down about 200 cm, although avalanches releasing on this layer represent an extremely low probability-high consequence scenario. Cornices in the region are very large. With spring temperatures, these are more likely to become weak and fail. They could provide a large enough trigger to release deep layers on slopes below.For more information on Spring Conditions and ways to mitigate risk, please visit the new Forecasters Blog Post.