THIS AVALANCHE FORECAST EXPIRED ON March 18, 2020 @ 11:46 pm
Avalanche Forecast published on March 18, 2020 @ 6:46 am
Issued by Cam Johnson - Flathead Avalanche Center

Whitefish Range
Swan Range

How to read the forecast

Enjoy mostly stable avalanche conditions today with isolated areas of concern. Recent north and east winds drifted slabs onto unusual slopes and in patterns that vary basin to basin. Look at each slope with a fresh set of eyes and steer around isolated pockets of wind drifted snow.

1. Low

?

Above 6500 ft.
Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.

1. Low

?

5000-6500 ft.
Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.

1. Low

?

3500-5000 ft.
Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.
    Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.
  • 1. Low
  • 2. Moderate
  • 3. Considerable
  • 4. High
  • 5. Extreme
Avalanche Problem 1: Wind Slab
  • Type ?
  • Aspect/Elevation ?
  • Likelihood ?
    Certain
    Very Likely
    Likely
    Possible
    Unlikely
  • Size ?
    Historic
    Very Large
    Large
    Small

Strong northerly and easterly winds this weekend drifted snow onto atypical slopes. Observers continue to report wind scoured surfaces and isolated slabs of drifted snow at mid and upper elevations. There is a possibility for small, more reactive slabs where moderate winds overnight caused localized drifting. Move quickly to wind sheltered locations if you feel hollow snow under your board or machine. This may require you to dig with your hand or poke with your ski pole to feel below the surface.

Forecast discussion

If you are on the hunt for some fresh news, I would recommend checking out the observation tab before heading into the mountains. Thank you to everyone who is contributing information to our community and assisting daily advisories.

To briefly summarize, people observed isolated loose wet activity on sunny aspects and others took note of wet/gloppy surfaces with no avalanche activity. Skiers and riders continue to report sluffing of loose dry snow on sheltered aspects at mid and upper elevation. No new natural or human triggered slab avalanches were reported yesterday, though people continue to find evidence of wind slabs from last weekend. Despite moderate wind speeds yesterday afternoon, little to no transport was observed.

In the past 12 hours, north and easterly winds reached speeds that are capable of transporting snow. There is, however, little snow left to be transported. In some areas where we received a few inches of low density snow after this weekend's storm, as shown here, you may be able to find a fresh, shallow drift of snow. These will be harmless in size, unless they catch you above a terrain trap. Fresh drifts will be easy to identify by their pillowy, textured surfaces. Expect the primary hazard to be old, stubborn wind slabs that blew in this past weekend. These are in unusual locations and may catch you off guard. The strong winds that raked the area last weekend caused large variation from basin to basin, especially in the Flathead Range and Glacier National Park. Some basins were left unscathed and others got scoured. Keep your feelers out there and your eyes open to avoid getting caught and dragged around by a stiff slab of snow.

Overnight temperatures plummeted into the low teens, leading us into a healthy melt-freeze cycle on aspects that get kissed by the sun. A sun crust and fairly cold temperatures today will limit wet loose activity. If temperatures do climb higher than forecast and the crust breaks down, seek out colder, north facing slopes. Be mindful of overhead cornice fall and give ridgelines a wide berth.

Weather and CURRENT CONDITIONS
weather summary

Cold northeast flow will bring cooler temperatures. Freezing levels will reach 5500 feet for a brief period during afternoon hours. Skies will be mostly clear with light winds and moderate gusts out of the northeast.

Two-Day Mountain Weather Forecast Produced in partnership with the Missoula NWS
For 5000 ft. to 7000 ft.
Wednesday Wednesday Night Thursday
Cloud Cover: Mostly Clear Mostly Clear Partly Cloudy
Temperatures: 25 to 32 deg. F. 7 to 13 deg. F. 20 to 29 deg. F.
Wind Direction: Northeast Northeast Northeast
Wind Speed: 9G22 13 17G28
Snowfall: 0" in. 0" in. 0" in.
Snow Line: 1500' 1500' 0'
Disclaimer

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.