Our thanks to Idaho State Parks and Recreation. We had another great winter of collaboration on avalanche classes and you can count on us continuing and expanding that in the future. IPAC would also like to thank those that assisted with our avalanche observations; especially Tom Eddy of Schweitzer Mountain Ski Patrol, Friends of IPAC and everyone who phoned in or emailed us, your assistance is invaluable and we enjoyed working with you and look forward to working with you in the coming winters.
SPRING TRAVEL TIPS
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 boot-tops 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.
In the high country the Panhandle is averaging a meager 49% of average for snowpack, the Spokane River basin 48%, and the Clearwater region is higher at about 71% of an average snowpack this year. The pack will melt out earlier this year and access to the high country is easy on forest roads. Where there is snow the conditions have been good due to persistent cold nights and warm, sunny days. On your ventures into the high country remember to respect old terra firma, the brown stuff, that sticks to your boots and tracks on the way up. Don’t rut up the roads and trails in your truck or ATV trying to get an extra 100 feet. Park before you get to the muddy sections and try to avoid them as much as possible. Just like your tracks in the snow, leave no trace. We’ll be back next year with the first winter snows. This picture should wet your whistle for one last trip to the mountains. You'll be glad you did.
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
Have a safe and pleasant weekend.