THIS AVALANCHE ADVISORY EXPIRED ON March 29, 2020 @ 7:04 amAvalanche Advisory published on March 28, 2020 @ 7:04 am
Issued by Melissa Hendrickson - Idaho Panhandle Avalanche Center
On March 25th, the Idaho Governor issued a stay-at-home order, joining Washington State where it was issued on March 23rd. Montana's was issued on March 26th. The orders are clear in encouraging people to stay at home to the maximum extent possible. Outdoor activity is allowed, but it is stressed that it be near to home; within walking distance. In order to stay in congruency with the State's orders and support the well being of our forecasters and their families we are closing the Avalanche Center for the season. As an Avalanche Center, we are asking everyone to follow the State's orders and stay out of the backcountry and stay home. We all need to do our part during this time of emergency. For more information, see the Announcements section.
The Avalanche Center will continue to provide support to search and rescue groups as well as respond to avalanche fatalities or serious avalanche accidents. But do your part to help make sure we don't have to participate in these functions: stay out of the backcountry and stay home.
Spring Avalanche Safety Message:
Spring is generally a safe time to travel in the mountains but there are some rules to live by. The safest and best conditions will exist after a good nighttime freeze. Dig a pit to see how deeply the freeze penetrated. This will give you an idea of how quickly the snow will become slushy and unstable. Get on the slopes early before the temperatures get too warm or the sun gets too intense. Mountain temperatures above 50 degrees should be an indicator that conditions are becoming unstable. Strong radiation can penetrate deep into the pack and destabilize weak layers. Steep south facing slopes are affected most rapidly by strong sun. If you are into the slush up to your boots or you’re laying on the throttle to move its time to get off the slope. By planning your route to take you to slopes just as they come into the sun and begin to thaw you can enjoy good, safe sliding. Always be careful around rock outcroppings because they hold heat and weaken the snow for some distance around them. Rain always weakens the snow pack and this time of year rain can lubricate ice crusts making the overlying layers more prone to slide. When we do get new snow watch for the type of surface it is bonding to. New snow on an ice crust that is experiencing melting during the day can be extremely unstable, especially if it is wind-loaded. In general, new snow will be more sensitive to radiation. Surface hoar can also be a weak layer in the spring so check under the new snow accumulation to make sure you’re not dealing with that little devil. Finally, keep track of extended periods of thawing, not only during the day but most importantly overnight. This will also decrease snow stability. Night-time temperatures below freezing are a must for good sliding conditions, and safe sliding conditions. The more nights in a row that freezing conditions occur, the more stable the snow is likely to be. Freezing conditions will usually accompany clear nights while overcast nights tend to trap heat.
Weather and CURRENT CONDITIONS
Avalanche conditions change for better or worse continually. Backcountry travelers should be prepared to assess current conditions for themselves, plan their routes of travel accordingly, and never travel alone. Backcountry travelers can reduce their exposure to avalanche hazards by utilizing timbered trails and ridge routes and by avoiding open and exposed terrain with slope angles of 30 degrees or more. Backcountry travelers should carry the necessary avalanche rescue equipment such as a shovel, avalanche probe or probe ski poles, a rescue beacon and a well-equipped first aid kit. For a recorded version of the Avalanche Advisory call (208)765-7323.
This website is owned and maintained by the Friends of the Idaho Panhandle Avalanche Center. Some of the content is updated by the USDA avalanche forecasters including the forecasts and some observational data. The USDA is not responsible for any advertising, fund-raising events/information, or sponsorship information, or other content not related to the forecasts and the data pertaining to the forecasts.