Use this page to view archived advisories. The table below shows the overall danger rating and the bottom line for the 20 most recent advisories. Click on the time and date link above each danger rating icon to view the full advisory for that day. Use the date chooser or the pager at the bottom to scroll through the older advisories.

E.g., Wednesday, June 19, 2024
E.g., Wednesday, June 19, 2024
E.g., Wednesday, June 19, 2024
Date the advisory was published:sort ascending Forecast Region
Click here to see the full advisory for 2020-02-12
February 12, 2020 at 6:36

Several parties triggered stiff slabs of drifted snow during yesterday's wind loading event.  Wind slabs a foot or more in thickness remain a lingering concern for the Swan and the Flathead Range, as well as Glacier National Park. Avoid pillowy looking surfaces that formed below ridgelines and on cross-loaded terrain features at mid and upper elevations. Give corniced ridgelines a wide berth since these still can be triggered by the weight of a person.

Flathead Range and Glacier National Park
Click here to see the full advisory for 2020-02-12
February 12, 2020 at 6:35

Several parties triggered stiff slabs of drifted snow during yesterday's wind loading event.  Wind slabs a foot or more in thickness remain a lingering concern for the Swan and the Flathead Range, as well as Glacier National Park. Avoid pillowy looking surfaces that formed below ridgelines and on cross-loaded terrain features at mid and upper elevations. Give corniced ridgelines a wide berth since these still can be triggered by the weight of a person.

Swan Range
Click here to see the full advisory for 2020-02-12
February 12, 2020 at 6:33

Enjoy generally stable avalanche conditions with isolated areas of wind drifted snow. This wind drifted snow should be easy to identify below recent cornice formation or pillow looking surfaces. If you see fresh drifts, steer around them.  Small slides can be consequential if they push you into a stand of trees or over a cliff band.

Whitefish Range
Click here to see the full advisory for 2020-02-11
February 11, 2020 at 7:01

Winds are increasing and conditions are changing. Watch for new and recent snow to drift into shallow slabs in wind-exposed locations.  These could be dangerous around terrain traps, or if they entrain or step down into older snow.  Wind sheltered terrain is serving up the safest and best quality riding right now. Mind your sluffs though. 

Whitefish Range
Click here to see the full advisory for 2020-02-11
February 11, 2020 at 6:57

Winds are increasing and conditions are changing. Watch for new and recent snow to drift into shallow slabs in wind-exposed locations.  These could be dangerous around terrain traps, or if they entrain or step down into older snow.  Wind sheltered terrain is serving up the safest and best quality riding right now. Mind your sluffs though. 

Flathead Range and Glacier National Park
Click here to see the full advisory for 2020-02-11
February 11, 2020 at 6:43

Winds are increasing and conditions are changing. Watch for new and recent snow to drift into shallow slabs in wind-exposed locations.  These could be dangerous around terrain traps, or if they entrain or step down into older snow.  Wind sheltered terrain is serving up the safest and best quality riding right now. Mind your sluffs though. 

Swan Range
Click here to see the full advisory for 2020-02-10
February 10, 2020 at 8:04

Though avalanche activity is quieting down, human triggered avalanches are still possible today.  Watch for lingering instabilities in steep terrain, especially in areas where winds have drifted or stiffened the snow.  Be careful around terrain traps where the consequences of a small slide could make for big trouble.  The safest riding today is in wind protected terrain. 

Flathead Range and Glacier National Park
Click here to see the full advisory for 2020-02-10
February 10, 2020 at 7:14

Though avalanche activity is quieting down, human triggered avalanches are still possible today.  Watch for lingering instabilities in steep terrain, especially on steep rollovers or drifted slopes.  The safest riding today is on wind-protected slopes less than about 40 degrees in steepness, free of trees, gullies, and cliff bands in the runouts. 

Swan Range
Click here to see the full advisory for 2020-02-10
February 10, 2020 at 7:08

Though avalanche activity is quieting down, human triggered avalanches are still possible today.  Watch for lingering instabilities in steep terrain, especially in areas where winds have drifted or stiffened the snow.  Be careful around terrain traps where the consequences of a small slide could make for big trouble.  The safest riding today is in wind protected terrain. 

Flathead Range and Glacier National Park
Click here to see the full advisory for 2020-02-10
February 10, 2020 at 6:43

Though avalanche activity is quieting down, human triggered avalanches are still possible today. Watch for lingering instabilities in steep terrain harboring drifted snow. Be careful around terrain traps where the consequences of a small slide could make for big trouble.  The safest riding today is in wind-protected terrain. 

Whitefish Range
Click here to see the full advisory for 2020-02-09
February 9, 2020 at 6:32

Shifting winds have built slabs over persistent weak layers on many aspects. They need time to heal. Avoid steep leeward slopes where soft slabs of drifted snow may be large enough to injure or bury you. In sheltered terrain, sluffs can entrain large amounts of snow and deep debris can pile up in terrain traps. Watch for rounded drifts below ridgelines and the sidewalls of gullies. Shooting cracks in drifted snow, and long running sluffs are signs of instability.

Whitefish Range
Click here to see the full advisory for 2020-02-09
February 9, 2020 at 6:26

Several parties had near misses with avalanches that broke in unexpected ways yesterday. Recent storm slabs resting on top of weak layers and crusts will be slow to heal. Conservative terrain choices and low slope angles are your ticket to safe riding today. Where the surface is unconsolidated, sluffs can entrain large amounts of snow and deep debris can pile up in terrain traps.

Swan Range
Click here to see the full advisory for 2020-02-09
February 9, 2020 at 6:25

Several parties had near misses with avalanches that broke in unexpected ways yesterday. Recent storm slabs resting on top of weak layers and crusts will be slow to heal. Conservative terrain choices and low slope angles are your ticket to safe riding today. Where the surface is unconsolidated, sluffs can entrain large amounts of snow and deep debris can pile up in terrain traps. Avoid slopes with overhead exposure to alpine start zones where deep slabs are still a concern.

Flathead Range and Glacier National Park
Click here to see the full advisory for 2020-02-08
February 8, 2020 at 6:00

Shifting winds will build fresh slabs on a variety of aspects. Avoid steep leeward slopes where soft slabs of drifted snow will grow throughout the day. In sheltered terrain, sluffs can entrain large amounts of snow and deep debris can pile up in terrain traps. Blowing snow, shooting cracks, and long running sluffs are signs of instability. The danger will be higher if snowfall exceeds expectations.

Whitefish Range
Click here to see the full advisory for 2020-02-08
February 8, 2020 at 5:56

A storm favoring the Swan and Flathead Ranges is creating dangerous avalanche conditions. Be conservative and avoid steep slopes where soft slabs of new and drifted snow may be large enough to injure or bury you. In sheltered terrain, sluffs can entrain large amounts of snow and deep debris can pile up in terrain traps. Recent avalanches, blowing snow, and shooting cracks are red flags. 

Swan Range
Click here to see the full advisory for 2020-02-08
February 8, 2020 at 5:54

A storm favoring the Swan and Flathead Ranges is creating dangerous avalanche conditions. Be conservative and avoid steep slopes where soft slabs of new and drifted snow may be large enough to injure or bury you. In sheltered terrain, sluffs can entrain large amounts of snow and deep debris can pile up in terrain traps. Recent avalanches, blowing snow, and shooting cracks are red flags. Be cautions under slopes with overhead exposure to large avalanche paths with alpine start zones.

Flathead Range and Glacier National Park
Click here to see the full advisory for 2020-02-07
February 7, 2020 at 6:47

Avoid being on or under steep, shady, upper-elevation slopes where the snowpack is broken by rocks, small cliffs, or convexities. In this terrain, the potential for natural and triggered slides that break near the ground lingers. The potential for triggered slides involving snow near the surface is isolated to very steep terrain with recently-formed slabs of drifted snow, or more than 10 inches of loose dry snow. 

Flathead Range and Glacier National Park
Click here to see the full advisory for 2020-02-07
February 7, 2020 at 6:31

Avalanche hazards are isolated to very steep terrain. You're most likely to find these pockets in upper elevation, leeward slopes near ridges and summits. Where the hazard exists, it can involve recently-formed slabs of drifted snow, or sluffs of loose, dry snow. Consider consequences as much as likelihood, and adhere to safe travel practices as insurance against surprises.

Whitefish Range
Click here to see the full advisory for 2020-02-07
February 7, 2020 at 6:31

Avalanche hazards are isolated to very steep terrain. You're most likely to find these pockets in upper elevation, leeward slopes near ridges and summits. Where the hazard exists, it can involve recently-formed slabs of drifted snow, or sluffs of loose, dry snow. Consider consequences as much as likelihood, and adhere to safe travel practices as insurance against surprises.

Swan Range
Click here to see the full advisory for 2020-02-06
February 6, 2020 at 7:04

On steep, mid- and upper-elevation slopes, you can trigger avalanches that break near the hard crust left by this weekend's tropical weather. These mostly involve recently-formed slabs of drifted snow on leeward and cross-loaded slopes. Avoid being on or under steep, shady, upper-elevation slopes where the snowpack is broken by rocks, small cliffs, or convexities. In this terrain, the potential for natural and triggered slides that break near the ground lingers. 

Flathead Range and Glacier National Park
Click here to see the full advisory for 2020-02-06
February 6, 2020 at 6:44

On steep, mid- and upper-elevation slopes, you can trigger avalanches that break near the hard crust left by this weekend's tropical weather. These mostly involve recently-formed slabs of drifted snow on leeward and cross-loaded slopes. Sluffs of loose, dry snow pose a hazard on steep slopes of any aspect. Be alert for clues to these hazards - shooting cracks, whumpfing, hard but hollow-feeling drifts, and, as always, recent natural or triggered avalanches.

Swan Range
Click here to see the full advisory for 2020-02-06
February 6, 2020 at 5:35

Be alert for isolated avalanche hazards on steep, upper-elevation terrain. These mostly involve recently-formed slabs of drifted snow on leeward and cross-loaded slopes. They will be small but dangerous above terrain traps. Be alert for clues to exceptions to the mostly stable conditions - shooting cracks, whumpfing, hard but hollow-feeling drifts, and, as always, recent natural or triggered avalanches.

Whitefish Range
Click here to see the full advisory for 2020-02-05
February 5, 2020 at 6:30

Sustained winds and new snow have broadened the avalanche danger in the Flathead Range and Glacier National Park. Freshly-formed slabs of wind drifted snow can be large enough to bury or injure you today. Remain hesitant of upper elevation, north- through east-facing terrain where deep slab avalanches have run as recently as this past weekend.

Flathead Range and Glacier National Park
Click here to see the full advisory for 2020-02-05
February 5, 2020 at 6:29

New snow and wind will increase the avalanche danger today by forming slabs of wind-drifted snow at mid and upper elevations. If you find 8 inches of new snow stack up, triggered slabs can be large enough to bury or injure you. Watch for blowing snow and pillowy-looking snow surfaces; these are cues to seek wind-sheltered terrain.

Swan Range
Click here to see the full advisory for 2020-02-05
February 5, 2020 at 6:28

New snow and wind will increase the avalanche danger today by forming slabs of wind-drifted snow at upper elevations. While most of these will be relatively small, they can be consequential if they push you over a cliff, into a stand of trees, or into a gully. Watch for blowing snow and pillowy-looking snow surfaces; these are cues to seek wind-sheltered terrain.

Whitefish Range
Click here to see the full advisory for 2020-02-04
February 4, 2020 at 6:55

A solid melt-freeze crust, cold temperatures, and lack of significant wind loading are contributing to mostly stable avalanche conditions. If you ascend above 7000 feet, choose terrain with a deep uniform snowpack away from rock bands and slopes that face north through east. Overburdened weak layers near the ground produced very destructive avalanches this weekend. These weak layers are slow to adjust and carry huge consequences.

Flathead Range and Glacier National Park
Click here to see the full advisory for 2020-02-04
February 4, 2020 at 6:54

Take advantage of a stable snowpack while it lasts. If snow accumulations pick up earlier than expected, new snow will slide easily as it falls onto a slick melt-freeze crust. Exercise safe travel protocols by traveling one at a time in avalanche terrain, keeping eyes on your partner.

Whitefish Range
Click here to see the full advisory for 2020-02-04
February 4, 2020 at 6:54

Take advantage of a stable snowpack while it lasts. If snow accumulations pick up earlier than expected, new snow will slide easily as it falls onto a slick melt-freeze crust. Exercise safe travel protocols by traveling one at a time in avalanche terrain, keeping eyes on your partner.

Swan Range
Click here to see the full advisory for 2020-02-03
February 3, 2020 at 7:17

Below Saturday's rain line, a solid melt-freeze crust has locked the snowpack in place.  Today is a beautiful day to climb high into the mountains, where conditions are softer and views are spectacular. Choose your terrain carefully as you ascend above the crust: stay on slopes with deep and uniform snowpacks.  Several very destructive deep slabs ran only two days ago: though buried persistent weak layers are difficult to trigger, they are also slow to adjust and carry huge consequences.  

Flathead Range and Glacier National Park
Click here to see the full advisory for 2020-02-03
February 3, 2020 at 6:39

C-c-c-c-rusty!  A solid melt-freeze crust has locked the snowpack in place.  Enjoy the beautiful weather and bombproof snowpack while it lasts. The current snow surface will likely become a problematic weak layer when we return to an active weather pattern starting mid-week.  

Swan Range

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