However weather and snow conditions will continue to be monitored at the Northwest Weather and Avalanche Center with the information which remains available. Additional forecasts will be issued when unusually severe avalanche conditions develop. When issued such forecasts will be available on the usual phone recordings and on the NWAC Web site. Please note that in areas retaining a significant winter snowpack, backcountry travelers face a continuing risk of avalanches during the springtime. We strongly advise that backcountry travelers continue to assess snowpack stability as they travel and project the effects of anticipated future weather on the snowpack when making route choices.
Some general notes regarding spring avalanches follow . . .
During fair spring weather the avalanche hazard is generally lowest during the night and early morning hours when surface snow refreezes due to heat loss to the surrounding atmosphere. During the day, intense solar radiation and warm air temperatures can rapidly melt and weaken surface snow layers and produce an increasing avalanche danger during the late morning and afternoon. Wet loose slide activity generally starts on east and southeast facing slopes receiving morning sunshine and progresses to west and southwest facing slopes during the afternoon. Therefore the safest time to cross potential avalanche terrain is during early morning hours before the surface snow begins to warm and weaken. This daily melt-freeze cycle is strongly affected by any cloud cover during the night since clouds at night limit radiational cooling and prevent freezing.