2019-20 West Central Montana Avalanche Conditions---!!! CONSIDERABLE !!!---3/31/2020

[Scott]

Current West Central Montana Avalanche Advisory Posted: Feb 20, 2020 06:04 am Is this email not displaying correctly? View it in your browser.

Avalanche Advisory for February 20, 2020 View Full Advisory » Today’s avalanche danger is rated MODERATE throughout the advisory area. Good morning, this is Andrew Schauer with the West Central Montana avalanche advisory for February 20, 2020. Today’s advisory is sponsored by Krispy Kreme. This advisory does not apply to operating ski areas, expires at midnight tonight, and is the sole responsibility of the U.S. Forest Service. Weather and Snowpack We have not received any snowfall in the past 24 hours. Winds have been blowing out of the southeast to southwest at 10-15 mph. Temperatures this morning are in the single digits to low teens F and will reach the high 20’s to mid 30’s in the mountains today. Winds will be 5-10 mph out of the southwest. Skies will remain clear through Saturday, and our next chance of snowfall will be Sunday morning. With clear skies and high temperatures reaching the mid 30’s through the end of the week, our primary concern will be loose wet avalanches. There is close to a foot and a half of unconsolidated snow near the surface that will quickly loose strength as temps rise. (video) Although they may not be huge, these avalanches can be dangerous if you are caught in the wrong terrain. Be on the lookout for red flags like roller balls, pinwheels, (photo) and other loose wet avalanches. If you notice the snowpack heating up, move to shaded aspects or head home for the day. We also need to be aware of the lingering persistent slab problem that we have been dealing with for most of the season. The snowpack does not respond well to rapid change, and a little bit of liquid water in the snowpack may be all we need to push buried weak layers to their breaking point. We have gotten reports of buried surface hoar in the Central and Southern Bitterroot, and we have seen weak facets buried around crusts throughout the advisory area. Approach steep slopes with caution, and make sure you dig a pit to identify and test these weak layers before committing to avalanche terrain since it will be possible to trigger an avalanche on one of these layers today. There is a thick layer of depth hoar buried under 1.5-2m of snow in the southern Bitterroot that still needs to be treated with caution. Today is not the day for big objectives down south. If you are trying to get on steeper slopes, find a shallow place to dig and look for weak, sugary snow at the ground. If you find it, pick another slope to ride. These avalanches are unlikely to fail in stability tests, but if you find the right spot on the slope it is still possible to trigger a very large avalanche. The Bottom Line The new snow at the surface is going to become reactive with warming temperatures and plenty of sunshine over the next two days. We will see loose wet avalanches on sunny slopes, and there is a chance that this rapid warming could activate persistent weak layers in the upper 2-3’ of the snowpack. Avoid sunny slopes as the day heats up, and use stability tests to assess these weak layers before committing to steep slopes. Your observations are extremely helpful! If you get out, please take a minute to fill out the observation form on our website (missoulaavalanche.org), or shoot us a quick email at info@missoulaavalanche.org. We offer a variety of avalanche courses throughout the winter. Our schedule may be found at the course offerings page on our website. We still have two spots left on our Level 1 course at Lolo Pass at the end of this month (2/27-3/1). If you are interested in enrolling, you can find info here, or email us with questions. The post Avalanche Advisory for February 20, 2020 appeared first on Missoula Avalanche.

 

[Scott]

Current West Central Montana Avalanche Advisory Posted: Feb 22, 2020 06:42 am Is this email not displaying correctly? View it in your browser.

Avalanche Advisory for February 22, 2020 View Full Advisory » The avalanche danger is LOW for the west central Montana backcountry. Low danger does not mean no avalanche danger. Use normal caution to travel in avalanche terrain today. Good morning, this is Travis Craft with the West Central Montana avalanche advisory for February 22, 2020. Today’s advisory is sponsored by Krispy Kreme. This advisory does not apply to operating ski areas, expires at midnight tonight, and is the sole responsibility of the U.S. Forest Service. Weather and Snowpack Mountain temperatures range from 17 F to 26 F in the region. In the Bitterroot, winds are 7 mph with gusts of 17 out of the SSW. In the northern part of the advisory area, winds are 20 mph and gusting 33 mph out of the WSW. No new snow overnight. The weather has been mild during the day, creating crusts on sun-exposed slopes. Temperatures have been dropping at night to single digits growing surface hoar. These temperature swings have created near-surface facets below the melt-freeze crust. The surface hoar, crust, and facet combination are worrisome once they become buried later this weekend. Overnight temperatures did not drop into single digits. Expect clouds to increase today slowly. Low does not mean no avalanche danger. Dig a pit before committing to any steep slope, pay attention to changing weather, and look for red flags. The primary avalanche problem is loose wet on steep, south-facing slopes. As cloud cover builds today, it should keep these slides small. If you see rollerballs on a slope, it is time to seek shadier less sun-exposed slopes. In the southern Bitterroot, persistent slab avalanches are an avalanche problem. There is a thick layer of depth hoar buried under 1.5-2m of snow that still needs to be treated with caution. If you are trying to get on steeper slopes, find a shallow place to dig and look for weak, sugary snow at the ground. If you find it, pick another slope to ride. These avalanches are unlikely to fail in stability tests. However, if you find the right spot on the slope, it is still possible to trigger a very large avalanche. Bottom Line Use normal caution to travel in avalanche terrain today. Continue to practice safe travel protocols in case you find an exception to a generally stable snowpack. Travel one at a time in avalanche terrain, carry a beacon, shovel, and probe, and stay alert for signs of instability. Dig a pit. Look for red flags. Pay attention to weather changes that will increase avalanche danger. Your observations are extremely helpful! If you get out, please take a minute to fill out the observation form on our website (missoulaavalanche.org), or shoot us a quick email at info@missoulaavalanche.org. We offer a variety of avalanche courses throughout the winter. Our current schedule is listed on the Missoulaavalanche.org avalanche education page. If you are interested in enrolling, you can find info here, or email us with questions. Ski and ride safe.

 

[Scott]

Current West Central Montana Avalanche Advisory Posted: Feb 24, 2020 07:23 am Is this email not displaying correctly? View it in your browser.

Avalanche Advisory for February 24, 2020 View Full Advisory » With new snow last night and more on the way, the avalanche danger today is rated CONSIDERABLE in West Central Montana. Good morning, this is Andrew Schauer with the West Central Montana avalanche advisory for Monday, February 24, 2020. Today’s advisory is sponsored by Gull boats and R.V. This advisory does not apply to operating ski areas, expires at midnight tonight, and is the sole responsibility of the U.S. Forest Service. Weather and Snowpack The mountains picked up 6-10” new snow overnight, equaling .6-.8” snow water equivalent (SWE). As of 6 AM the highest totals are in the the Central bitterroot, with 11” new snow equaling .8” SWE. Winds are currently 15-25 mph out of the west, and gusts reached 76 mph last night. We will see 4-6” snow throughout the day today, with heavier snowfall in the afternoon. Winds will be 15-20 mph out of the west with gusts reaching 35, and mountain temperatures will be in the mid- to upper- 20’s. Nearly a foot of new snow fell onto a suspect surface last night. Clear skies and warm temperatures over the past few days have developed melt-freeze crusts on solar aspects, while growing surface hoar and facets on shady slopes (photo, photo, photo). These weak layers are not widespread, but the snowpack will need time to adjust to the new load. With more snow and moderate winds throughout the day, The likelihood of triggering an avalanche will increase. Our primary avalanche concern is wind slab avalanches, which will be easy to trigger on wind-loaded slopes steeper than 30 degrees. These avalanches will break 1-2’ deep, and will be big enough to carry and bury a person. Yesterday, riders reported a large wind slab avalanche near Lake Elsina in the Seeley Lake area (photos, details). Avalanches like these will be easy to trigger on wind-loaded slopes today. Storm slabs are also on the radar for today. Close to a foot of new snow falling on crusts or weak layers will make it easy to trigger an avalanche up to a foot deep on most slopes in the advisory area today. Be on the lookout for more red flags such as shooting cracks and recent avalanches, which are a clear sign that the snowpack is unstable and it is likely to trigger an avalanche. The Bottom Line Today is not the day to push it into steep, consequential terrain. Look for red flags such as shooting cracks, recent avalanche activity, and continued loading throughout the day, which are all clear signs of dangerous avalanche conditions. Take the time to dig a pit and do a quick stability test to see how well the new snow is bonding to the old snow surface before committing to any slope steeper than 30 degrees today. Your observations are extremely helpful! If you get out, please take a minute to fill out the observation form on our website (missoulaavalanche.org), or shoot us a quick email at info@missoulaavalanche.org. We offer a variety of avalanche courses throughout the winter. Our schedule may be found at the course offerings page on our website. Check out the list, and get yourself enrolled in one of our many courses this winter! The post Avalanche Advisory for February 24, 2020 appeared first on Missoula Avalanche.

 

[Scott]

Current West Central Montana Avalanche Advisory Posted: Feb 25, 2020 06:37 am Is this email not displaying correctly? View it in your browser.

Avalanche Advisory for February 25, 2020 View Full Advisory » The avalanche danger for the west central Montana backcountry is CONSIDERABLE on wind loaded slopes. All other slopes the danger is MODERATE. New snow and wind have created dangerous avalanche conditions on leeward slopes. Use caution on all other slopes before committing to them. Good morning, this is Travis Craft with the West Central Montana avalanche advisory for February 25, 2020. Today’s advisory is sponsored by Krispy Kreme. This advisory does not apply to operating ski areas, expires at midnight tonight, and is the sole responsibility of the U.S. Forest Service. Weather and Snowpack Mountain temperatures range from 12 F to 22 F in the region. In the Bitterroot, winds are 9 mph with gusts of 14 out of the WSW. In the northern part of the advisory area, winds are 14 mph and gusting 18 mph out of the WSW. Overnight we have received 4 to 6 new inches of snow. The storm totals are 6 to 20 inches of new snow in the last 48 hours. The Seeley lake area and Bitterroot were favored in this last storm cycle. The primary avalanche problem is wind drifted snow on leeward slopes. Yesterday near the Bitterroot divide and Granite pass, I found 3 to 4 foot slabs on leeward slopes. Jeff and Andrew found 1 foot wind slabs in the Rattlesnake. I saw two natural wind slab avalanches yesterday that were big enough to carry and bury a person. Look for small to large wind slabs on leeward slopes. Watch for blowing snow and rounded, textured, drifts. Shooting cracks are a sign of unstable wind slabs. These slabs, if triggered, could step down into deeper layers into the snowpack. The second avalanche concern is new snow. New snow fell on a variety of old snow surfaces. Dig a pit to see how the new snow is bonding to old snow surfaces. Look for red flags. I saw several natural small loose snow avalanches yesterday. Use small test slopes to see how the new snow is bonding before committing to terrain over 30 degrees. The final avalanche problem is persistent slab avalanches. The new load of snow has stressed the weak layers in our snowpack. There are facets in our snowpack. Dig a pit to the crust from 02/02/2020. Needles and debris can identify this crust from the wind event on February 02/01/2020. There is another melt-freeze crust closer to the surface with facets underneath it. Perform pit tests to see how reactive these layers are. There were slides triggered on facets in the top 1 to 3 feet of the snowpack over the weekend(Public Observations). Jeff was in the southern Bitterroot over the weekend. The depth hoar and structure is suspect. Avoid slopes where this structure is present. Depth hoar is a fickle beast and can not be trusted. If you want to commit to avalanche terrain, do your homework. Dig in a shallow spot (2 m or less), and look for weak, sugary snow at the ground. If you find it, choose another slope to ski or ride. Bottom Line Complex avalanche conditions require choosing simple terrain. Choose sheltered lower angle less than 30 degrees slopes today before committing to any steeper slopes. Dig a pit and look for stripes in the snow to identify weak layers. Perform a pit test to see how reactive these layers are. Choose a shallow spot to see if you have weak sugary snow at the bottom of the snowpack if you do choose another slope. Travel one at a time in avalanche terrain, carry a beacon, shovel, and probe, and stay alert for signs of instability. Look for red flags. Use small test slopes to see how the new snow is bonding. Education Your observations are extremely helpful! If you get out, please take a minute to fill out the observation form on our website (missoulaavalanche.org), or shoot us a quick email at info@missoulaavalanche.org. We offer a variety of avalanche courses throughout the winter. Go to our course offerings page on our website. Check out the list and get yourself enrolled in one of our many courses this winter! Ski and ride safe. The post Avalanche Advisory for February 25, 2020 appeared first on Missoula Avalanche.

 

[Scott]

Current West Central Montana Avalanche Advisory Posted: Feb 27, 2020 06:45 am Is this email not displaying correctly? View it in your browser.

Avalanche Advisory for February 27, 2020 View Full Advisory » The avalanche danger is LOW this morning and will increase to MODERATE this afternoon in the west central Montana backcountry. Warming temperatures will increase the avalanche danger. Good morning, this is Travis Craft with the West Central Montana avalanche advisory for February 27, 2020. Today’s advisory is sponsored by Gull boats and R.V. This advisory does not apply to operating ski areas, expires at midnight tonight, and is the sole responsibility of the U.S. Forest Service. Weather and Snowpack Mountain temperatures range from 17 F to 28 F in the region. In the Bitterroot, winds are 9 mph with gusts of 14 out of the SW. In the northern part of the advisory area, winds are 17 mph and gusting 20 mph out of the W. Overnight a trace to 2 inches of new snow. Today, temperatures will rise above freezing in the mountains. Winds will be light with gusts to 30 mph. These conditions will create wet avalanche problems today. Pay attention to changing snow conditions. The primary concern today is loose wet releases with warming temperatures. When you start to see rollerballs, it is time to go to shadier aspects. If the snow surface starts to feel punchy and wet it is time to head home. The second concern is cornice fall. Cornices are enormous right now. Warming temperatures will weaken these giants. Give these beasts a wide berth because they break farther back than anticipated. Persistent slabs are a concern in the southern Bitterroot. Depth hoar at the bottom of the snowpack can not be trusted. Choose a shallow spot to dig. If you find weak sugary snow at the bottom of your pit, choose a different slope where this structure is not present. In the Rattlesnake and Seeley Lake areas, wind slabs are an avalanche problem. Leeward slopes were loaded yesterday and were sensitive to human triggers (video). Watch for blowing snow and rounded, textured, drifts. Shooting cracks are a sign of unstable wind slabs. Bottom Line Changing weather equals changing avalanche conditions. Warming temperatures throughout the day will increase the likelihood of wet avalanche activity. Dig a pit before committing to any steep slope. Choose a shallow spot to see if you have weak sugary snow at the bottom of the snowpack if you do choose another slope. Travel one at a time in avalanche terrain, carry a beacon, shovel, and probe, and stay alert for signs of instability. Look for red flags. Give cornices a wide berth. Education Your observations are extremely helpful! If you get out, please take a minute to fill out the observation form on our website (missoulaavalanche.org), or shoot us a quick email at info@missoulaavalanche.org. We offer a variety of avalanche courses throughout the winter. Go to our course offerings page on our website. Check out the list and get yourself enrolled in one of our many courses this winter! Ski and ride safe. The post Avalanche Advisory for February 27, 2020 appeared first on Missoula Avalanche.

 

[Scott]

Current West Central Montana Avalanche Advisory Posted: Feb 29, 2020 06:22 am Is this email not displaying correctly? View it in your browser.

Avalanche Advisory for February 29, 2020 View Full Advisory » The avalanche danger is MODERATE in the west central Montana backcountry. Use caution when choosing slopes to ride on today. Good morning, this is Travis Craft with the West Central Montana avalanche advisory for February 29, 2020. Today’s advisory is sponsored by Gull boats and R.V. This advisory does not apply to operating ski areas, expires at midnight tonight, and is the sole responsibility of the U.S. Forest Service. Weather and Snowpack Mountain temperatures are below freezing in the region. In the Bitterroot, winds are 17 mph with gusts of 28 out of the West. In the northern part of the advisory area, winds are 29 mph and gusting 46 mph out of the West. Overnight a trace to 2 inches of new snow fell. We are shifting back to winter with a cold front pushing into the area this morning, dropping temperatures, moderate to strong winds, and light accumulations of snow. New snow and wind will increase the avalanche danger. The primary avalanche problem is persistent slabs. Yesterday, Andrew was able to find buried surface hoar on shaded north-facing slopes near Lolo pass. The buried surface hoar propagated easily in pit tests. This layer is buried about a foot deep. Overall this layer is very spotty in its distribution. Dig a pit and look for a thin stripe of snow and perform a pit test. In the southern Bitterroot, depth hoar at the bottom of the snowpack can not be trusted. Choose a shallow spot to dig. If you find weak sugary snow at the bottom of your pit, choose a different slope where this structure is not present. Bottom Line Today, we shift back into winter after a balmy day of warm temperatures. Changing weather equals changing avalanche conditions. New snow will be landing on a variety of old snow surfaces. Use small test slopes to see how the new snow is bonding. Look for small wind slabs to form on leeward slopes and be sensitive to human triggers. Dig a pit 4 feet deep and look for stripes in the snowpack. Perform a pit test to evaluate these layers. Travel one at a time in avalanche terrain, carry a beacon, shovel, and probe, and stay alert for signs of instability. Look for red flags. Give cornices a wide berth. Education Your observations are extremely helpful! If you get out, please take a minute to fill out the observation form on our website (missoulaavalanche.org), or shoot us a quick email at info@missoulaavalanche.org. We offer a variety of avalanche courses throughout the winter. Go to our course offerings page on our website. Check out the list and get yourself enrolled in one of our many courses this winter! Ski and ride safe. The post Avalanche Advisory for February 29, 2020 appeared first on Missoula Avalanche.

 

[Scott]

Current West Central Montana Avalanche Advisory Posted: Mar 03, 2020 06:46 am Is this email not displaying correctly? View it in your browser.

Avalanche Advisory for March 3, 2020 View Full Advisory » The avalanche danger is MODERATE in wind loaded terrain and LOW in all other terrain the west central Montana backcountry. Good morning, this is Jeff Carty with the West Central Montana avalanche advisory for March 3, 2020. Today’s advisory is sponsored by The Trail Head. This advisory does not apply to operating ski areas, expires at midnight tonight, and is the sole responsibility of the U.S. Forest Service. Weather and Snowpack Mountain temperatures will be warm today, potentially rising to 40º above 6000′. Below 6000′ temperatures have already risen to above 32º. The snow line will be around 5000′. Winds are strong, 35 mph with gusts of 50 mph out of the west. Gusts to 60 mph are possible. We’ve had between 1″-3″ new snow overnight and 1″-2″ is forecast for today. Tonight holds the possibility of a bit more snow, 3″-4″ in the Seeley-Swan area and 1″-2″ elsewhere in the forecast area. Overall our snowpack has consolidated well after Friday’s warm temps. If instabilities exist they are very isolated. These include buried surface hoar in very sheltered north aspects and some shallow crust/facet combos around last week’s crusts. They are worth investigating with a pit if you are skiing steep terrain. The primary avalanche problem is wind slabs. Yesterday in the Rattlesnake, Bitterroot and Lolo Pass we observed wind slabs beginning to form. Overnight winds to 50mph built these further and they will continue to grow throughout the day with gusts forecast to 60mph. Winds are forecast to affect lower elevations so windslab may be more widespread than normally encountered. Be aware of cross loading as you travel in the mountains today. Wet loose avalanches may be an issue at elevations lower than 6000′ today, where temperatures are forecast to rise as high as 47º. In the southern Bitterroot, depth hoar at the bottom of the snowpack is still a concern. Choose a shallow spot to dig. If you find weak sugary snow at the bottom of your pit, choose a different slope where this structure is not present. Bottom Line Strong winds are building wind slabs at a variety of elevations, avoid steep wind loaded terrain. Very isolated pockets of a buried surface hoar and crust/facet layer exist. Perform a pit test to evaluate these layers. Depth hoar in the southern Bitterroot is a low likelihood, high consequence problem and still deserves caution. Wet loose avalanches may be a concern below 6000′ today. Travel one at a time in avalanche terrain, carry a beacon, shovel, and probe, and stay alert for signs of instability. Look for red flags. Give cornices a wide berth. Education Your observations are extremely helpful! If you get out, please take a minute to fill out the observation form on our website (missoulaavalanche.org), or shoot us a quick email at info@missoulaavalanche.org. We offer a variety of avalanche courses throughout the winter. Go to our course offerings page on our website. Check out the list and get yourself enrolled in one of our many courses this winter! Ski and ride safe. The post Avalanche Advisory for March 3, 2020 appeared first on Missoula Avalanche.

 

[Scott]

Current West Central Montana Avalanche Advisory Posted: Mar 05, 2020 06:49 am Is this email not displaying correctly? View it in your browser.

Avalanche Advisory for March 5, 2020 View Full Advisory » The avalanche danger is CONSIDERABLEin wind loaded terrain and MODERATE in all other terrain the west central Montana backcountry. Good morning, this is Jeff Carty with the West Central Montana avalanche advisory for March 5, 2020. Today’s advisory is sponsored by The Trail Head. This advisory does not apply to operating ski areas, expires at midnight tonight, and is the sole responsibility of the U.S. Forest Service. Weather and Snowpack Over the past 48 hours westerly winds have blown up to: 54mph with gusts to 77 mph at Point 6 80 mph at Lolo Pass There were sustained strong winds for over 24 hours throughout the forecast area. Do to local terrain affects multiple aspects are impacted by these winds. Winds are currently light and forecast to be light with strong gusts throughout the day. Mountain temperatures have ranged from: 15º to 33º above 6000’ and are forecast to rise as high as 49º today. Snow accumulation in the past 48hr is roughly: 10” in the Seeley-Swan 5” in the Rattlesnake 8″ at Lolo Pass 8” new in the central Bitterroot 3″ in the southern Bitterroot Our primary concern is wind slab. These have grown to over three feet thick in some areas, are very sensitive and likely to be triggered by a skier or rider. Yesterday at Lolo, Travis was getting 10’ long shooting cracks while touring. Snowbowl was closed due to wind, expect extensive wind slab in the Rattlesnake. Wind transport and loading have been extensive and considerable throughout the forecast area (video). Due to the strength of the wind, slabs may be lower on slopes than normally encountered, and deposited on multiple aspects. Steep wind loaded terrain >33º should be approached with caution. In other areas such as the Gash and the first bowl at Wishard Ridge, wind slabs were not an issue, the snowpack has bonded well despite wind transport. There is a lot of variability throughout the forecast area but the extent of the wind effect means you should approach any avalanche slope with caution and evaluate the touchiness of windslab before preseeding. Where there is not wind loading the snowpack is, overall, well bonded and stable. There are, however, exceptions. Buried surface hoar can be found in isolated areas. It is present and reactive on sections of Mt. Fuji (video) and maybe lurking on other sheltered north slopes. Dig a pit, perform tests and look for it before committing to steep terrain. There are near-surface facets growing underneath the 02/28 crust. While it is not currently an issue, it may become a problem layer with a load of new snow on it. In the southern Bitterroot, depth hoar at the bottom of the snowpack is still a concern. Choose a shallow spot to dig. If you find weak sugary snow at the bottom of your pit, choose a different slope where this structure is not present. Warm, above seasonal temperatures today and Friday will increase the risk of wet loose avalanches, especially on sun warmed aspects. The extent of warming will loosen bonds within the snowpack and may make layers that have been unreactive more sensitive, increasing the risk of slab avalanches. The hazard from warming will increase throughout the day with rising temperatures. Bottom Line Strong winds have built dangerous wind slabs at a variety of elevations, avoid steep wind loaded terrain. Very isolated pockets of a buried surface hoar and crust/facet layer exist. Perform a stability test to evaluate these layers. Depth hoar in the southern Bitterroot is a low likelihood, high consequence problem and still deserves caution. Wet loose avalanches are an increasing risk throughout the day as temperatures rise. Travel one at a time in avalanche terrain, carry a beacon, shovel, and probe, and stay alert for signs of instability. Look for red flags. Give cornices a wide berth, they will be more likely to fall with the warming. Education Your observations are extremely helpful! If you get out, please take a minute to fill out the observation form on our website (missoulaavalanche.org), or shoot us a quick email at info@missoulaavalanche.org. We offer a variety of avalanche courses throughout the winter. Go to our course offerings page on our website. Check out the list and get yourself enrolled in one of our many courses this winter! Ski and ride safe.

 

[Scott]

Current West Central Montana Avalanche Advisory Posted: Mar 07, 2020 06:45 am Is this email not displaying correctly? View it in your browser.

Avalanche Advisory for March 7, 2020 View Full Advisory » The avalanche danger is MODERATE in the west central Montana backcountry. Good morning, this is Jeff Carty with the West Central Montana avalanche advisory for March 7, 2020. Today’s advisory is sponsored by The Trail Head. This advisory does not apply to operating ski areas, expires at midnight tonight, and is the sole responsibility of the U.S. Forest Service. Weather and Snowpack Following the winds Wednesday we’ve had a couple days of warm, relatively calm high pressure. There has been no significant precipitation and minimal wind transport. Temperatures have reached highs of: 42º at Point 6, 7897′ 56º In the southern Missions at 6330′ 57º at Lolo Pass at 5240′ 53º In the central Bitterroot at 6400’ 47ºin the southern bitterroot at 7940′ Temperatures remained above freezing at upper elevations in the southern and central Bitterroot for the past two nights and throughout the entire forecast region last night. Temperatures will remain above freezing until midday today when the freezing level will begin to descend to about 4000′ tonight. Avalanche hazard will decrease as the snowpack refreezes. All East, South, and West aspects have been heavily affected by sun. Yesterday, rollerballs were abundant. Loose, wet avalanches were entraining snow as they descended. North aspects above 6500’ were holding some dry snow, however, warm overnight temps may have effected these aspects as well. The warm temps have led to rapid bonding of the windslab that was a concern on Thursday. Overall this problem has stabilized. However, in isolated areas, it may still be possible to trigger a wind slab. Cornice fall remains an issue. Cornices are giant and are more likely to fail with the warm temperatures. Our main problem is wet loose avalanches, the potential size of these is increasing with elevated overnight temperatures. These will remain a threat as long as the snow surface is above freezing. Sustained warm temperatures have loosened bonds within the snowpack and may make layers that have been unreactive more sensitive, increasing the risk of slab avalanches. Wet avalanche problems are hard to predict, standard stability tests are not effective. If the snow is wet, grippy and heavy, you are seeing rollerballs or wet loose avalanches move off avalanche terrain or to more shaded slopes. Practice more caution in areas where there are lingering instabilities. Isolated instabilities to be aware of include: Buried surface hoar. It is present and reactive on sections of Mt. Fuji (video) and maybe lurking on other sheltered north slopes. Dig a pit, perform tests and look for it before committing to steep terrain. There are near-surface facets growing around the 02/28 crust. While it is not currently an issue, it may become a problem layer with a load of new snow on it. Facets around the 02/23 crust are now 9” deep and are reactive in very isolated areas. They failed and propagated very easily on an east slope in the Rattlesnake yesterday, but were not found on other slopes in the area. We found this layer in the Lolo pass area on a SE slope in the last week, and it may be present in other isolated areas. In the southern Bitterroot, depth hoar at the bottom of the snowpack is still an uncertainty. Warm temps such as we are experiencing could reawaken dormant depth hoar layers. Choose a shallow spot to dig. If you find weak sugary snow at the bottom of your pit, choose a different slope where this structure is not present. Bottom Line Sustained warm temperatures have created a wet loose avalanche hazard. There is an increasing risk of slab avalanches due to thaw instabilities where mountain temps have remained above freezing overnight. Very isolated pockets of a buried surface hoar and crust/facet layers exist. Depth hoar in the southern Bitterroot is a low likelihood, high consequence problem and still deserves caution. Travel one at a time in avalanche terrain, carry a beacon, shovel, and probe, and stay alert for signs of instability. Look for red flags. Give cornices a wide berth, they will be more likely to fall with the warming. Education Your observations are extremely helpful! If you get out, please take a minute to fill out the observation form on our website (missoulaavalanche.org), or shoot us a quick email at info@missoulaavalanche.org. We offer a variety of avalanche courses throughout the winter. Go to our course offerings page on our website. Check out the list and get yourself enrolled in one of our many courses this winter! Ski and ride safe. The post Avalanche Advisory for March 7, 2020 appeared first on Missoula Avalanche.

 

[Scott]

Current West Central Montana Avalanche Advisory Posted: Mar 10, 2020 06:39 am Is this email not displaying correctly? View it in your browser.

Avalanche Advisory for March 10, 2020 View Full Advisory » A lack of new snowfall, cool overnight temperatures, and the absence of buried persistent weak layers in the snowpack means avalanches are unlikely and the avalanche danger is rated LOW in West Central Montana for today. Good morning, this is Andrew Schauer with the West Central Montana avalanche advisory for Tuesday, March 10, 2020. Today’s advisory is sponsored by ZillaState. This advisory does not apply to operating ski areas, expires at midnight tonight, and is the sole responsibility of the U.S. Forest Service. Weather and Snowpack At 5 AM, mountain temperatures are in the high teens to low 20’s and winds are blowing 10-25 mph out of the west to southwest, with gusts up to 34 mph. There was no new snow overnight. Winds today will be 15-20 mph out of the west with gusts to 38, and mountain temperatures will be in the mid-20’s to low 40’s under partly cloudy skies. Light snow showers will return to our advisory area Wednesday, with our chance for snow increasing towards the end of the week. It has been five days since the last significant snowfall in our advisory area, and the snowpack is gaining strength. With mountain temperatures consistently staying below freezing at night, the snow near the surface has been able to re-freeze after warmer daytime temps, and it is unlikely that a human will trigger an avalanche today. However, low danger does not mean no danger. As temperatures creep above freezing during the day, a little sun exposure will increase your chances of triggering a loose wet avalanche near the snow surface. Yesterday Todd and I toured into the Kootenai drainage in the central Bitterroot and saw signs of recent loose wet activity (photo), as well as large chunks of cornices that had broken off naturally within the past week. We also need to be aware of isolated instabilities lurking deeper in the snowpack. Jeff got unstable test results on a few east-facing slopes in the Rattlesnake yesterday, with extended column tests failing above a crust buried about a foot deep. Although this problem is far from widespread, it is worth taking the 15 minutes to dig a pit and do a quick stability test to assess these buried weak layers before stepping out into steeper terrain. The Bottom Line This time of year can provide the most stable snowpack in our advisory area, finally making it possible to step out into steeper terrain. But be careful- we are not entirely out of the woods yet. Take time to dig a quick pit before putting yourself in avalanche terrain. Be on the lookout for pockets of weak snow that may fail in a stability test. Be aware of deteriorating stability as the day heats up and clue into clear signs like pinwheels and rollerballs, which are indicators that the surface snow is losing strength and it is time to move to shaded aspects or head back to the car. Avoid traveling directly below large cornices, which can fail as they heat up throughout the day. As always, only expose one person at a time to avalanche terrain. Your observations are extremely helpful! If you get out, please take a minute to fill out the observation form on our website (missoulaavalanche.org), or shoot us a quick email at info@missoulaavalanche.org. We still have several avalanche courses remaining this season. If you are interested in enrolling, you can find info at the course offerings page on our website, or email us with questions. The post Avalanche Advisory for March 10, 2020 appeared first on Missoula Avalanche.

 

[Scott]

Current West Central Montana Avalanche Advisory Posted: Mar 12, 2020 06:23 am Is this email not displaying correctly? View it in your browser.

Avalanche Advisory for March 12, 2020 View Full Advisory » Up to 6” of new snow with moderate winds will make avalanches possible on wind-loaded slopes. For today, the avalanche danger will be MODERATE on wind-loaded slopes and LOW elsewhere in West Central Montana. Good morning, this is Andrew Schauer with the West Central Montana avalanche advisory for Thursday, March 12, 2020. Today’s advisory is sponsored by ZillaState. This advisory does not apply to operating ski areas, expires at midnight tonight, and is the sole responsibility of the U.S. Forest Service. Weather and Snowpack In the past 24 hours, a small system dropped 6” of snow in the southern Missions, 4” in the Rattlesnake, and a trace in the rest of the advisory area. Winds have been 10-20 mph out of the west with gusts up to 48 mph. As of 5 AM, mountain temperatures are in the high teens to low 20’s. Today, winds will blow 10-15 mph out of the west with gusts to 25, and mountain temperatures will be in the low 20’s to upper 30’s. Clouds will move in this afternoon as a low pressure system brings cold temperatures tonight through the weekend. Up to 6” of new snow last night with moderate to strong winds will make it possible for a human to trigger wind slabs up to a foot deep today. These avalanches will be most likely near Seeley Lake, which received the most snow in the past 24 hours. Yesterday, Todd and I toured in the Bitterroot and found stable conditions, but strong winds were already transporting snow. Jeff recorded a similar observation in the Rattlesnake. With low snow totals last night, wind slabs will be smaller and less likely in these areas today. However, even small avalanches can present a dangerous hazard in consequential terrain. Look for freshly drifted snow and avoid wind-loaded slopes, especially above terrain traps like cliffs, trees, or gullies. It will also be important to keep an eye on solar aspects, especially at lower elevations. Loose wet avalanches (photo) will be possible as temperatures rise throughout the day. Pay attention to changing snow conditions. If you notice you are punching through heavy, wet snow, it is time to move to shaded slopes or head home for the day. The Bottom Line New snow and moderate winds have built reactive wind slabs on leeward slopes. For today it will be important to identify and avoid wind loaded slopes. As the snow heats up during the day, be aware of the increasing likelihood of loose wet avalanches, especially if you notice pinwheels, rollerballs, or if you are sinking up past your boots in heavy, wet snow. Your observations are extremely helpful! If you get out, please take a minute to fill out the observation form on our website (missoulaavalanche.org), or shoot us a quick email at info@missoulaavalanche.org. We still have several avalanche courses remaining this season. If you are interested in enrolling, you can find info at the course offerings page on our website or email us with questions. The post Avalanche Advisory for March 12, 2020 appeared first on Missoula Avalanche.

 

[Scott]

Current West Central Montana Avalanche Advisory Posted: Mar 14, 2020 06:41 am Is this email not displaying correctly? View it in your browser.

Avalanche Advisory for March 14, 2020 View Full Advisory » Strong winds and new snow are building sensitive wind slabs. For today, the avalanche danger will be MODERATE on wind-loaded slopes and LOW elsewhere in West Central Montana. Good morning, this is Andrew Schauer with the West Central Montana avalanche advisory for Saturday, March 14, 2020. Today’s advisory is sponsored by ZillaState. This advisory does not apply to operating ski areas, expires at midnight tonight, and is the sole responsibility of the U.S. Forest Service. Weather and Snowpack Last night we received 7” of new snow in the southern Missions and 3” in the Rattlesnake, while the Bitterroot stayed high and dry. Winds are blowing a sustained 60 mph out of the east at Point Six, with gusts to 80 mph. In the rest of the area, winds are 10-20 mph out of the east with gusts to 40 mph. Mountain temperatures are in the single digits to low 20’s. Snow will continue through tonight, with 4-6” expected throughout the advisory area. Winds will blow 15-25 mph out of the west with gusts to 40, and mountain temperatures will stay in the low teens to low 20’s. High winds are drifting new snow into fresh wind slabs up to two feet deep, which will be easily triggered in steep terrain. Winds have been blowing out of the east, which means we can expect to see wind-loading in areas that are usually getting scoured. Yesterday we saw snow blowing up and over cornices in the Seeley Lake area (video), and Todd found sensitive wind pockets in the Southern Bitterroot. Be alert while you travel in the backcountry today. Look for and avoid slopes that have been recently loaded. If you notice clear signs of instability, like recent avalanches or cracks shooting out from your skis or snowmobile, stick to low-angle terrain or seek other slopes that have not been loaded. Although it has been over a month since the last avalanche was reported failing deeper in the snowpack, it is worth noting that we are still finding poor structure in the southern Bitterroot. Yesterday Todd and his partner found weak snow near the ground in a thin snowpack up Tin Cup creek and chose a safer route to ski out. This structure does not exist everywhere, and it is unlikely that a human will trigger an avalanche on this layer. However, the consequences of triggering a deep persistent slab avalanche are severe. Avoid slopes in the southern Bitterroot with an unusually thin snowpack sitting on above weak, sugary snow at the ground. The Bottom Line Strong easterly winds are moving new snow into sensitive wind slabs that will be easy to trigger in steep terrain today. Look for loading in unusual locations, and avoid steep slopes with fresh drifts of wind-loaded snow. As always, dig a quick pit before committing to steep terrain, and pick an alternate route if you get unstable test results or if you notice red flags like shooting cracks or recent avalanches. Your observations are extremely helpful! If you get out, please take a minute to fill out the observation form on our website (missoulaavalanche.org), or shoot us a quick email at info@missoulaavalanche.org. The post Avalanche Advisory for March 14, 2020 appeared first on Missoula Avalanche.

 

[Scott]

Current West Central Montana Avalanche Advisory Posted: Mar 17, 2020 06:26 am Is this email not displaying correctly? View it in your browser.

Avalanche Advisory for March 17, 2020 View Full Advisory » The avalanche danger is LOW this morning and MODERATE this afternoon in the west central Montana backcountry. Warming temperatures increase the avalanche danger this afternoon. Good morning, this is Travis Craft with the West Central Montana avalanche advisory for March 17, 2020. Today’s advisory is sponsored by Krispy Kreme. This advisory does not apply to operating ski areas, expires at midnight tonight, and is the sole responsibility of the U.S. Forest Service. Weather and Snowpack Mountain temperatures range from 17 F to 25 F in the region. In the Bitterroot, winds are 11 mph with gusts of 14 out of the SSE. In the northern part of the advisory area, winds are 14 mph and gusting 19 mph out of the W. Yesterday, we found a reasonably stable snowpack throughout the advisory area. Cornices are very large, and a cornice fall in the last couple of days triggered a small slab avalanche in the bass creek drainage. In the Rattlesnake, skier triggered, and natural loose wet avalanches were the primary concern.(video) Near Lake Dinah stability was good, and loose wet avalanches on sun-exposed slopes were the main problem. Overnight temperatures dropped into the high teens or twenties. Temperatures will increase into the mid 40’s today. Look for rollerballs and pinwheels on sun-exposed slopes. These will be clues to find more sheltered and shadier aspects. True North slopes are still holding dry snow above 6500 feet. The primary avalanche concern is loose wet avalanches in the afternoon. Warm temperatures on sun-exposed slopes will increase the avalanche danger today. Rollerballs are clues to find shadier slopes. The second avalanche problem is cornice fall. Warming temperatures will weaken cornices. Give these giants a wide berth and travel quickly below them. Bottom Line Use normal caution to travel in avalanche terrain today. Continue to practice safe travel protocols in case you find an exception to a generally stable snowpack. Travel one at a time in avalanche terrain, carry a beacon, shovel, and probe, and stay alert for signs of instability. Dig a pit. Look for red flags. As the snow heats up during the day, be aware of the increasing likelihood of loose wet avalanches, especially if you notice pinwheels, rollerballs, or if you are sinking up past your boots in heavy, wet snow. Pay attention to weather changes that will increase avalanche danger. Your observations are extremely helpful! If you get out, please take a minute to fill out the observation form on our website (missoulaavalanche.org), or shoot us a quick email at info@missoulaavalanche.org. Ski and ride safe. The post Avalanche Advisory for March 17, 2020 appeared first on Missoula Avalanche.

 

[Scott]

Current West Central Montana Avalanche Advisory Posted: Mar 19, 2020 06:18 am Is this email not displaying correctly? View it in your browser.

Avalanche Advisory for March 19, 2020 View Full Advisory » The avalanche danger is LOW in the west central Montana backcountry. Low danger does not mean no avalanche danger. Good morning, this is Travis Craft with the West Central Montana avalanche advisory for March 19, 2020. Today’s advisory is sponsored by Krispy Kreme. This advisory does not apply to operating ski areas, expires at midnight tonight, and is the sole responsibility of the U.S. Forest Service. Weather and Snowpack Mountain temperatures range from 17 F to 30 F in the region. In the Bitterroot, winds are 5 mph with gusts of 8 out of the NE. In the northern part of the advisory area, winds are 9 mph and gusting 11 mph out of the ENE. Yesterday in the Lost Horse drainage in the Bitterroot and Rattlesnake, we found isolated avalanche problems. We found large cornices and glide cracks in Lost Horse. In the Rattlesnake, the main avalanche problem was small wind slabs. Overnight temperatures dropped into the low twenties. We are starting to transition to a spring cycle on many slopes. Temperatures are forecasted to be below average as cold air from Canada moves into the area. This, combined with cloud cover, will keep the avalanche danger Low today. The primary avalanche problem is wind slabs in isolated pockets. Look for these small slabs on ridgelines at higher elevations. Glide cracks and avalanches are functions of warming temperatures and terrain features. Avoid glide cracks and terrain with granite slabs underlying the snowpack. Cornices are large, give them a wide berth. Bottom Line Low avalanche danger does not mean no avalanche danger. Use normal caution to travel in avalanche terrain today. Continue to practice safe travel protocols in case you find an exception to a generally stable snowpack. Travel one at a time in avalanche terrain, carry a beacon, shovel, and probe, and stay alert for signs of instability. Dig a pit. Look for red flags. If the clouds break today and the sun comes out, look for rollerballs and pinwheels. They are clues that the snowpack is changing. Your observations are extremely helpful! If you get out, please take a minute to fill out the observation form on our website (missoulaavalanche.org), or shoot us a quick email at info@missoulaavalanche.org. Ski and ride safe. The post Avalanche Advisory for March 19, 2020 appeared first on Missoula Avalanche.

 

[Scott]

Current West Central Montana Avalanche Advisory Posted: Mar 21, 2020 06:33 am Is this email not displaying correctly? View it in your browser.

Avalanche Advisory for March 21, 2020 View Full Advisory » The avalanche danger is LOW in the west central Montana backcountry. Use normal caution when traveling today to assess the snowpack and avalanche danger. Good morning, this is Travis Craft with the West Central Montana avalanche advisory for March 21, 2020. Today’s advisory is sponsored by Krispy Kreme. This advisory does not apply to operating ski areas, expires at midnight tonight, and is the sole responsibility of the U.S. Forest Service. Weather and Snowpack Mountain temperatures range from 21 F to 30 F in the region. In the Bitterroot, winds are 5 mph with gusts of 10 out of the SSW. In the northern part of the advisory area, winds are 20 mph and gusting 29 mph out of the W. Yesterday, we found a snowpack that was generally stable. We observed loose wet activity from a few days ago near Moose Lake in the Bitterroot. Near Lil St. Joe in the Bitterroot, we saw some cornice failure from warming temperatures. In the Missions, we got reports of large loose wet releases from yesterday or the day before. Overall our snowpack is stable. The snowpack is going through melt-freeze cycles on all slopes except true north ones where you can still find some dry snow. Most slopes have a firm supportable crust. Today temperatures are expected to rise into the low 40’s or high 30’s in the advisory area with some cloud cover. Temperatures are already rising on snotels this morning. Expect to find generally stable conditions today. Pay attention to warming temperatures, and if the clouds break, could create some loose wet activity on sun-exposed steep terrain. The primary avalanche problem is loose wet avalanches on steep sun-exposed slopes. Cornices are large give them, and the slopes below them respect. Bottom Line Low avalanche danger does not mean no avalanche danger. Use normal caution to travel in avalanche terrain today. Continue to practice safe travel protocols in case you find an exception to a generally stable snowpack. Travel one at a time in avalanche terrain, carry a beacon, shovel, and probe, and stay alert for signs of instability. Dig a pit. Look for red flags. If the clouds break today and the sun comes out, look for rollerballs and pinwheels. They are clues that the snowpack is changing. Most ski resorts are closed. Check each ski area page to find its uphill ski policies. Remember, when the ski resort is closed, there is no ski patrol for rescue or avalanche mitigation. The rules for travel and riding are the same for the backcountry. Here is a link to some online material.KBYG Your observations are extremely helpful! If you get out, please take a minute to fill out the observation form on our website (missoulaavalanche.org), or shoot us a quick email at info@missoulaavalanche.org. Ski and ride safe. The post Avalanche Advisory for March 21, 2020 appeared first on Missoula Avalanche.

 

[Scott]

Current West Central Montana Avalanche Advisory Posted: *|RSSITEMATE|* Is this email not displaying correctly? View it in your browser.

Dear Friends, We at Missoula Avalanche recognize the growing uncertainty that you are facing right now and share your concern. Please know that we are committed to helping you stay safe and wish everyone the best during these challenging times. As a public safety organization, our top priority is keeping our staff, volunteers, and the backcountry community safe. Due to the nationwide spread of COVID-19, we have suspended all educational programs and events through April. This includes Know Before You Go programs, Snowpack Talks, and event fundraisers. We will continue to monitor the situation and follow all recommendations from our Board of Directors, CDC, and state and local authorities. We recognize that the mountains are a source of refuge and joy for the community, especially during these uncertain times. The West Central Montana Avalanche Center (WCMAC) remains dedicated to delivering the information you need for heading into the mountains and returning home safely. The WCMAC intends to continue it's seasonal operations as scheduled before shifting to snowpack updates in April. The WCMAC's ability to connect communities to high-quality avalanche information is the sum of its parts. As local guide services suspend operations and ski areas closures take effect, your public observations are doing more than ever before. To help ensure this essential information is available to everyone, we encourage you to fill out the Missoulaavalanche.org observation form. Your ongoing observation information benefits WCMAC forecasters and the public at large. You can help us, help you by continuing to submit your backcountry observations this year. As you get out, please remember the following. COVID-19 is creating unprecedented challenges for our healthcare system. Please remember that social distancing guidelines apply to outdoor travel. We ask that you follow the CDC recommendations, and if you do go out to recreate, please adhere to the necessary precautions. It is advisable to avoid carpooling with people who live outside of your household, keep your groups small, and avoid social gatherings at the parking lot. Ski areas have closed for the season. During this time, ski areas are unmitigated avalanche terrain without staff to provide professional help if you are caught or injured. Ski areas have the legal right to close terrain to the public, both on leased Forest Service and private land, and many do so. Please understand and respect the uphill travel policies of each area you plan to visit. If you choose to head out, we encourage you to take all precautions necessary to safeguard the health and safety of your group and others. It is crucial to remain aware of avalanche conditions and possess the rescue equipment and on snow skillsets needed for safe backcountry travel. Please remember to read the advisory, weather summary, and reassess snowpack conditions throughout your day. As a community-powered organization, you provide us with the resources for funding avalanche forecasting and educational program operations. We want to express our ongoing thanks to the individuals, businesses, and agencies who invest in our work. We are grateful to have your continued support and the ability to make a collective impact on avalanche safety. Taking the necessary precautions has paused our event fundraiser plans for this spring. We, like many in the community, are grappling with how to address diminishing revenue. The postponing of events and fundraisers impact avalanche center operations this year and our ability to fund programs next season. If you utilize these services throughout the season or were planning on supporting us through an event, we hope that you will still consider a donation online if you can do so. Your continued support makes avalanche forecasting, awareness, and education throughout west-central Montana possible. Thank you for being part of the Missoula Avalanche team and helping us ensure that everyone who ventures into the backcountry has the tools they need to make good decisions and come home safely. Sincerely, Patrick Black -- Patrick Black Executive Director West Central Montana Avalanche Foundation info@missoulaavalanche.org | missoulaavalanche.org PO Box 72, Missoula, Montana, 59806

 

[Scott]

Current West Central Montana Avalanche Advisory Posted: Mar 24, 2020 06:47 am Is this email not displaying correctly? View it in your browser.

Avalanche Advisory for March 24, 2020 View Full Advisory » The avalanche danger is LOW in the west central Montana backcountry. Use normal caution when traveling today to assess the snowpack and avalanche danger. Good morning, this is Jeff Carty with the West Central Montana avalanche advisory for March 24, 2020. Today’s advisory is sponsored by onX maps. This advisory does not apply to operating ski areas, expires at midnight tonight, and is the sole responsibility of the U.S. Forest Service. Weather and Snowpack Mountain temperatures range from 22F to 27 F and are forecast to reach into the 40s above 6000′ today. Winds are forecast to be light, 11-13mph with strong gusts. Cloud cover will likely keep the sun off the slopes today so the snow will not soften up much. We’ve received 0.1″-0.3″ of snow water equivalent (SWE), or about 1-3 inches of new snow overnight throughout the forecast area. Snow may begin falling this afternoon with 2-4″ expected at higher elevations. As of yesterday conditions hadn’t changed much since Friday. Lower elevation, <6500’, and southern aspects continued to be in a melt-freeze cycle with good corn skiing if your timing was right. Too much sun or warming and things got downright sticky and heavy. With cooler temperatures forecast, cloud cover and a dusting of new snow, south faces may pose the problem of being too solid to get an edge in and sliding uncontrollably may be an issue in steeper sections. North faces continued to have dry and in places soft snow. We’ve observed a variety of surfaces out there (video) including well-developed surface hoar and near surface facets that were readily sluffing on steep terrain. While not an issue currently, with further loading by wind or snowfall these could form a problematic weak layer. Pay attention to new snow depths and consistency as you tour. If the forecast snow piles up sufficiently it may consolidate into slabs and could be touchy. Look out for red flags such as shooting cracks. While not currently much of a risk, further accumulation, and terrain traps will increase the consequence of small slides. The new snow we receive will be sluffing on all old snow surfaces out there today and loose dry avalanches are our primary concern above 6500’. Below 6500’ loose wet avalanches are possible, if the clouds part and we get sun on upper elevations wet loose avalanches are possible above 6500’ as well. Large cornices are still lurking out there, and some recent cornice fall was observed this weekend. Avoid traveling below cornices and stay well away from the edge when above. Glide cracks are opening in isolated areas of the Bitterroot and Missions. These are the result of the entire snowpack sliding on a wet ground surface and they can slowly open for weeks at a time. They can also fail suddenly and unpredictably producing avalanches the full depth of the snowpack. Stay well away from slopes where glide cracks are present. Bottom Line Generally stable avalanche conditions exist throughout the forecast area. The main concerns are loose dry and loose wet avalanches. If new snow accumulates sufficiently to form slabs it will likely be touchy as it is landing on surface hoar, near surface facets and sun crust. Low avalanche danger does not mean no avalanche danger. Continue to practice safe travel protocols in case you find an exception to a generally stable snowpack. Travel one at a time in avalanche terrain, carry a beacon, shovel, and probe, and stay alert for signs of instability. Dig a pit. Look for red flags. Please take a moment to read this message from Missoula Avalanche, Greater than the Sum of Our Parts. Your observations are extremely helpful! If you get out, please take a minute to fill out the observation form, or shoot us a quick email at info@missoulaavalanche.org. Ski and ride safe. The post Avalanche Advisory for March 24, 2020 appeared first on Missoula Avalanche.

 

[Scott]

Current West Central Montana Avalanche Advisory Posted: Mar 26, 2020 06:45 am Is this email not displaying correctly? View it in your browser.

Avalanche Advisory for March 26, 2020 View Full Advisory » The avalanche danger is LOW in the west central Montana backcountry. Use normal caution when traveling today to assess the snowpack and avalanche danger. Good morning, this is Jeff Carty with the West Central Montana avalanche advisory for March 26, 2020. Today’s advisory is sponsored by onX Maps. This advisory does not apply to operating ski areas, expires at midnight tonight, and is the sole responsibility of the U.S. Forest Service. Weather and Snowpack Mountain temperatures range from 13ºF to 25ºF and are forecast to reach into the low 30s above 6000’ today. Winds are forecast to be light with moderate to strong gusts out of the west. In the last 48 hours, we’ve received 0.3-0.7″ of snow water equivalent (SWE) or about 3-7 inches of new snow throughout the forecast area. The Gash had about 4” of fresh at upper elevations yesterday and the area around Chief Joseph Pass had 4-8”. Cooler temps, cloudy skies, and snow showers throughout the day made it feel like winter in the mountains again. Southern aspects didn’t get much sun the past two days, but it’s been enough to consolidate and begin bonding the new snow. Loose wet avalanche potential could increase with solar warming today, if the clouds part for long enough, but they should be small and manageable. North faces have dry new snow that is overlying a variety of surfaces including surface hoar, near surface facets and crusts. The surface hoar under the new snow, where present, is well preserved and will likely persist as a weak layer for a while. Yesterday loose dry avalanches were running fast and far indicating how slippery these surfaces are. The new snow is shallow, has not consolidated and overall slab avalanches are not yet a concern. However, we did kick off a very small 4” deep slab on a steep NE aspect off the Gash indicating there is isolated potential. With further loading by wind or snowfall more consequential slabs could form. Isolated areas may have received enough snow to form thicker slabs and winds may have loaded slopes at ridge top. Pay attention to snow depth and consistency as you tour and check for the presence of a low density band of surface hoar under the new snow. Even small slides and loose dry avalanches can be consequential with terrain traps. In the southern Bitterroot yesterday, Travis and Andrew found the depth hoar that formed earlier this season is still persisting at the base of the snowpack and still propagating in snowpit tests. It is unlikely for a skier or rider to trigger an avalanche on this layer, however, a rain on snow event or significant loading could cause it to fail (video). Large cornices are still lurking out there, and recent cornice fall was observed this past weekend. Avoid traveling below cornices and stay well away from the edge when above. Glide cracks are opening in isolated areas of the Bitterroot and Missions. These are the result of the entire snowpack sliding on a wet ground surface and they can slowly open for weeks at a time. They can also fail suddenly and unpredictably producing avalanches the full depth of the snowpack. Stay well away from slopes where glide cracks are present. Bottom Line Generally stable avalanche conditions exist throughout the forecast area. However, low avalanche danger does not mean no avalanche danger. The main concern is loose dry avalanches on northern aspects. These could entrain enough snow to knock you off your feet and push you into hazards and may require management. Small soft slabs may be present in isolated areas. Loose wet avalanches are possible on southern aspects. Continue to practice safe travel protocols in case you find an exception to a generally stable snowpack. Travel one at a time in avalanche terrain, carry a beacon, shovel, and probe, and stay alert for signs of instability. Dig a pit. Look for red flags. Please take a moment to read this message from Missoula Avalanche, Greater than the Sum of Our Parts. Your observations are extremely helpful! If you get out, please take a minute to fill out the observation form, or shoot us a quick email at info@missoulaavalanche.org. Ski and ride safe. The post Avalanche Advisory for March 26, 2020 appeared first on Missoula Avalanche.

 

[Scott]

Current West Central Montana Avalanche Advisory Posted: Mar 28, 2020 06:46 am Is this email not displaying correctly? View it in your browser.

Avalanche Advisory for March 28, 2020 View Full Advisory » The avalanche danger in the west central Montana backcountry is MODERATE in wind loaded terrain and LOW in all other terrain. Good morning, this is Jeff Carty with the West Central Montana avalanche advisory for March 28, 2020. Today’s advisory is sponsored by onX Maps. This advisory does not apply to operating ski areas, expires at midnight tonight, and is the sole responsibility of the U.S. Forest Service. Weather and Snowpack Mountain temperatures range from 18º to 26º and are forecast to reach into the low 40s above 6000’ today. Winds are forecast to be low with moderate to strong gusts out of the west. In the last 48 hours, we’ve received an average of 0.5″ of snow water equivalent (SWE) or about 5″ inches of new snow throughout the forecast area. The northern portion of the forecast area received a bit more while the southern Bitterroot received less. The snow has been trickling in and slowly piling up over the past week. Yesterday at the Gash we found 6-8” of dry powder at upper elevations. Wind is further loading start zones just below ridge top. The new snow is overlying a variety of surfaces including surface hoar, near surface facets, and crusts. We are finding the surface hoar on protected northerly aspects. Distribution is somewhat patchy but where found it is well preserved. It and will likely persist as a weak layer for a while. Yesterday near Gash Point we ski cut a northeast slope that released a D1 avalanche, with an 8” crown, on the surface hoar over a crust layer. Similar avalanches are possible on similar slopes. With further loading by wind or snowfall more consequential slabs could form. Pay attention to snow depth and consistency as you tour and check for the presence of a low density band of surface hoar under the new snow. Avoid steep start zones near ridgetop. Travis and Andrew found up to 8″ of new snow in the southern Missions yesterday with wintery conditions and loose snow avalanches above 6500′ (video). Loose dry avalanches were running fast and far on north aspects yesterday, They are likely in steep, >35º terrain today. Cooler temps and mostly cold skies have kept solar warming to a minimum and there has been minimal wet loose activity in the past couple of days. Wet loose avalanches are possible on sun warmed slopes today, although cloud cover should keep them to a minimum. Large cornices are still lurking out there, cornice fall is possible. Avoid traveling below cornices and stay well away from the edge when above. Glide cracks are opening in isolated areas of the Bitterroot and Missions. These are the result of the entire snowpack sliding on a wet ground surface and they can slowly open for weeks at a time. They can also fail suddenly and unpredictably producing avalanches the full depth of the snowpack. Stay well away from slopes where glide cracks are present. Bottom Line It is possible to trigger small slab avalanches that are failing on a surface hoar layer in steep wind loaded terrain. Generally stable avalanche conditions exist in all other terrain. Loose dry avalanches are possible on northern aspects. These could entrain enough snow to knock you off your feet and push you into hazards and may require management. Loose wet avalanches are possible on southern aspects. Continue to practice safe travel protocols in case you find an exception to a generally stable snowpack. Travel one at a time in avalanche terrain, carry a beacon, shovel, and probe, and stay alert for signs of instability. Dig a pit. Look for red flags. Please take a moment to read this message from Missoula Avalanche, Greater than the Sum of Our Parts. Your observations are extremely helpful! If you get out, please take a minute to fill out the observation form, or shoot us a quick email at info@missoulaavalanche.org. Ski and ride safe. The post Avalanche Advisory for March 28, 2020 appeared first on Missoula Avalanche.

 

[Scott]

Current West Central Montana Avalanche Advisory Posted: Mar 31, 2020 06:35 am Is this email not displaying correctly? View it in your browser.

Avalanche Advisory for March 31, 2020 View Full Advisory » With new snow overnight and more on the way, human triggered avalanches are likely and the avalanche danger is rated CONSIDERABLE today in West Central Montana. Good morning, this is Andrew Schauer with the final West Central Montana avalanche advisory for the season on Tuesday, March 31, 2020. Today’s advisory is sponsored by all of you who made donations and participated in our fundraising events this season. Thank you all, this operation would not be possible without your support. This advisory does not apply to operating ski areas, expires at midnight tonight, and is the sole responsibility of the U.S. Forest Service. Weather and Snowpack Winter is still hanging on in West Central Montana. As of 5 am, we have received 8” of new snow in the Bitterroot equaling .6” snow water equivalent (SWE). Storm totals are lower in the Rattlesnake and Seeley Lake areas, with 4” of new snow equaling .4” SWE. Winds are 12-20 mph out of the west, with gusts to 38 mph. Mountain temperatures are in the mid- to upper 20’s F this morning, and will rise to the mid- 30’s during the day. Snow continues today, with another 5-8” expected in Bitterroot and 4-6″ in the Rattlesnake and near Seeley Lake by tomorrow morning. Winds will blow 15-20 mph out of the southwest with gusts in the high 40’s. Light snowfall will continue through tomorrow. With nearly a foot of new snow in the past 24 hours, and more on the way, it will be easy for a person to trigger storm slab avalanches up to 12” deep throughout the advisory area today. These will propagate the widest on northerly aspects that developed weak snow at the surface over the past two weeks. We have received reports of avalanches failing at this interface over the past few days at Gash Point (photo, details) as well as the Rattlesnake (details). Moderate winds are drifting snow into sensitive wind slabs up to 2 feet deep. A fresh wind slab will be more dense than unaffected storm snow, and will usually fail in a stability test. Be on the lookout for clear indicators of these avalanches like shooting cracks and recent avalanche activity. If you are noticing these clear signs of instability, choose low-angle terrain. Dry loose avalanches will be likely in steep terrain on all aspects today. While it is unlikely that these avalanches will be big enough to bury somebody, they can have serious consequences in dangerous terrain. Avoid exposure to terrain traps like cliffs and gullies today, and be aware that these avalanches will run far and fast on slopes that had developed crusts prior to the storm. The Bottom Line Today is not the day to push it into steep terrain. While all of this new snow will dramatically improve riding conditions across the advisory area, it will also make it very easy to trigger an avalanche big enough to bury you. Be thorough in your snowpack assessment, and pay attention to clear signs of instability like recent avalanches and shooting cracks. Be conservative with your terrain choices today, and give the snowpack a few days to adjust to the new snow once the storm passes. We will continue posting observations periodically throughout the spring. If you get out, please take a minute to fill out the observation form on our website (missoulaavalanche.org), or shoot us a quick email at info@missoulaavalanche.org. Please take a moment to read this message from Missoula Avalanche, Greater than the Sum of Our Parts. The post Avalanche Advisory for March 31, 2020 appeared first on Missoula Avalanche.