?
Above 6500 ft.
?
5000-6500 ft.
?
3500-5000 ft.
Up to 12" of dry snow on shaded aspects may warm if a greenhouse effect develops from today's cloud cover. Rollerballs will be the first sign that this dry snow is becoming moist. Sunny aspects, which went through a wet avalanche cycle last week, will offer a safer alternative. If you or your machine are sinking into wet snow, avoid traveling above terrain traps and move to lower angled terrain.
Glide avalanches and developing glide cracks have been noted on sunny aspects throughout our area. The "crack" forms when the season's snowpack slowly moves downslope, separating itself from the snow above. Predicting when a glide crack will fail is difficult. Failure is often catastrophic and avoiding slopes harboring glide cracks is the best way to manage this uncertainty.
Despite sunny skies, comfortable temperatures and good spring snow conditions, observations Saturday were sparse. Quality corn snow is found on SE-S-SW aspects due to the combination of last week's heat wave and recent cold overnight temperatures. This snow is generally stable and was still quality corn at 3 p.m. in the Noisy/Jewel Basin yesterday. East and West aspects are slowly transitioning to this same spring snow surface. On these slopes, loose wet instabilities may develop. Rollerballs are the first sign of a warming surface. Northerly aspects are holding surprisingly dry snow from several weak storms earlier this week and in early March. The depth of the new snow increases with elevation with up to 12" found in Noisy Basin and 6-8" in the Middle Fork above 6000'. These slopes have the most potential to develop wet avalanche instabilities. Today's partly cloudy skies will limit direct solar input on sunny aspects, but will potentially create a greenhouse effect which will warm dry snow on northerly aspects. Pay attention to new snow totals as you gain elevation. If the greenhouse effect comes to fruition, move to a southerly aspect for a safer and more enjoyable experience.
The late winter/spring snowpack in NW Montana generally presents us with glide avalanche problems. Numerous glide avalanches and glide cracks have been noted on sunny aspects over the past several weeks. These are generally located on slopes with a beargrass or smooth rock surface and occur on the same slopes each year. Glide avalanches can fail whenever their flanks or base lose the strength needed to support the slabs. Forecasting glide slab release is extremely difficult. The best course of action is to stay out from under them and enjoy slopes that remain covered in snow.
EDUCATION: The Scoop on Spring Touring: Curious about spring snow and safe travel techniques? This is the talk for you. Join FAC Lead Forecaster Blase Reardon for a FREE one hour talk on spring conditions in the Flathead. The talk begins at 6:30 p.m. Thursday, April 11th at Rocky Mountain Outfitters in Kalispell. That evening is also a community night for the Friends of the Flathead Avalanche Center at Sweet Peaks in Kalispell. Stop by for a sweet treat and then head down the street to get the scoop on spring conditions.
Increasing clouds through the day ahead of a weak system entering our area tonight. Light snow and rain are expected tonight and tomorrow.
| Sunday | Sunday Night | Monday | |
|---|---|---|---|
| Cloud Cover: | Mostly Cloudy | Mostly Cloudy | Mostly Cloudy |
| Temperatures: | 35 to 45 deg. F. | 25 to 30 deg. F. | 35 to 45 deg. F. |
| Wind Direction: | Southwest | South | Northeast |
| Wind Speed: | 5 to 10, gusting to 20 | 5 to 10, gusting to 20 | 5 to 10, Gusting to 20 |
| Snowfall: | 0 in. | 0 in. | 0 in. |
| Snow Line: | 4500 | 4500 | 4500 |
This forecast applies only to backcountry areas outside established ski area boundaries. The forecast describes general avalanche conditions and local variations always occur. This forecast expires at midnight on the posted day unless otherwise noted. The information in this forecast is provided by the USDA Forest Service who is solely responsible for its content.
