THIS AVALANCHE ADVISORY EXPIRED ON March 20, 2019 @ 6:45 am
Avalanche Advisory published on March 19, 2019 @ 6:45 am
Issued by Melissa Hendrickson - Idaho Panhandle Avalanche Center

St. Regis Basin/Silver Valley

bottom line

The mountain weather forecast is dipping barely below freezing at nights above 5000' for the next couple of days. Day time temperatures are predicted to be downright blazing, which will cause rapid change on the snowpack.  Expect the wet slide potential to increase as the day warms up.  If you are seeing natural pinwheels and rollerballs, head to the cooler side. If there isn't a cooler side, head to mellower slopes.  

How to read the advisory

St. Regis Basin/Silver Valley

How to read the advisory

The mountain weather forecast is dipping barely below freezing at nights above 5000' for the next couple of days. Day time temperatures are predicted to be downright blazing, which will cause rapid change on the snowpack.  Expect the wet slide potential to increase as the day warms up.  If you are seeing natural pinwheels and rollerballs, head to the cooler side. If there isn't a cooler side, head to mellower slopes.  

3. Considerable

?

Above Treeline
Dangerous avalanche conditions. Careful snowpack evaluation, cautious route-finding and conservative decision-making essential.

3. Considerable

?

Near Treeline
Dangerous avalanche conditions. Careful snowpack evaluation, cautious route-finding and conservative decision-making essential.

3. Considerable

?

Below Treeline
Dangerous avalanche conditions. Careful snowpack evaluation, cautious route-finding and conservative decision-making essential.
    Dangerous avalanche conditions. Careful snowpack evaluation, cautious route-finding and conservative decision-making essential.
Avalanche Problem 1: Loose Wet
  • Type ?
  • Aspect/Elevation ?
  • Likelihood ?
    Certain
    Very Likely
    Likely
    Possible
    Unlikely
  • Size ?
    Historic
    Very Large
    Large
    Small

At high elevations, the thin sun crust will break down quickly as the temperatures rise during the day.  At the mid and lower elevations, temperatures might not even drop low enough for a crust to form over the next couple of nights.  Wet avalanche activity will increase as the slopes heat up.  Managing this problem is a matter of getting out your compass and managing your aspects. Stay ahead of the problem by hitting slopes in the order the sun hits them, going from East to West. As the slopes heat up, look for natural rollerballs or pinwheels. Does the snow seem sloppy and not supporting your weight, whether on skis or a sled? These are signs that it is time to move on and head to cooler aspects or mellower terrain.  Wet slides, like any avalanche, are most dangerous above terrain traps and in long, open gullies.  

Avalanche Problem 2: Glide
  • Type ?
  • Aspect/Elevation ?
  • Likelihood ?
    Certain
    Very Likely
    Likely
    Possible
    Unlikely
  • Size ?
    Historic
    Very Large
    Large
    Small

We have several known culprit locations for glides around the forecast area and many other locations that are probable.  As the weather warms, these will continue to grow and slide.  They are unpredictable and can entrain large amounts of snow when they release.  If you see large cracks on a slope that is getting warmed by the sun, time to relocate.  

recent observations

With the warming temperatures and the fast change in the snowpack, there is the potential for deeper layers in the snowpack to "wake" back up by the rapid change in temperature and added moisture trickling down through the pack.  Silver Mountain was reporting yesterday that they had propegation on an older buried surface hoar layer.  Another avalanche problem which might become noteworthy is cornice failure.  The increasing temperatures weaken cornices, which can cause them to fail.  It takes an extended period of warming for this to occur, so keep an eye on the temperatures and keep this in the back of your mind as you are travelling.  As of Sunday, the glide on Tiger looked like it might have been opening up, I'd love to hear a report if it's slid yet! 

Remember, if the snow is sloppy, it's time to relocate out of avalanche terrain!  A spring snowpack gives you big natural signs of instability so spend your time making quality observations of what mother nature is telling you.  Play your game of aspects right and you can have a good corn harvest!  Just use avalanche common sense when you are in pursuit of the spring goodness.  

 

 

Weather and CURRENT CONDITIONS
Two-Day Mountain Weather Forecast Produced in partnership with the Spokane NWS
For 2000 ft. to 4000 ft.
Tuesday Tuesday Night Wednesday
Weather: Sunny Clear Sunny
Temperatures: 55 deg. F. 34 deg. F. 58 deg. F.
Wind Direction: E E E
Wind Speed: 7-9 7 3-7
Expected snowfall: 0 in. 0 in. 0 in.
For 4000 ft. to 6000 ft.
Tuesday Tuesday Night Wednesday
Weather: Sunny Mostly Clear Sunny
Temperatures: 43 deg. F. 28 deg. F. 46 deg. F.
Wind Direction: E E E
Wind Speed: 9-13 16 11-15
Expected snowfall: 0 in. 0 in. 0 in.
Disclaimer

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.