2017-18 West Central Montana Avy Conditions: 4/21/18--SECOND final forecast.

[Scott]

Missoula Avalanche
Avalanche Advisory for February 1, 2018

moderate danger
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The current avalanche danger is MODERATE in the west central Montana backcountry. Human triggered avalanches are possible. Heightened avalanche conditions exist on specific terrain features. Evaluate snow and terrain carefully and identify features of concern.

Good morning, this is Travis Craft with the West Central Montana Avalanche Center’s avalanche advisory for February 01, 2018. This danger rating 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 11 F to 24 F in the region. In the Bitterroot winds are 8 mph with gusts of 10 mph out of the South. In the northern part of the advisory area, winds are reading 4 mph with gusts of 8 mph out of the SW. The forecast area received 4 to 16 inches of new snow in the last 48 hours.

Logan and I went to Twin Lakes in the central Bitterroot yesterday. We found 14 new inches of light, low-density snow. We saw cornice development from the last week of winds and, saw wind loaded slopes near ridge tops and some terrain was cross-loaded. Our weak layers did not propagate in stability tests. Overall the snowpack is strengthening.

The primary avalanche problem is wind slabs. Look for rounded pillows of snow near ridgelines and on cross-loaded slopes. Recognize signs of instability such as cracking in the surface snow. There have been reports of skier triggered wind slabs that were between 1 to 2 feet deep on cross-loaded slopes. Avoid wind loaded slopes.

The second avalanche problem is loose dry releases. The new snow is light, low-density and did not form a cohesive slab. Look for large sluffs to be triggered easily today. These should not be a problem to manage unless they knock you off your machine or down and carry you into a terrain trap.

The final avalanche concern is persistent slabs. Our buried surface hoar on shadier aspects and crusts on more sun exposed slopes, still need a pit dug to see if they are reactive. Before committing to a steep slope, dig a pit 3 feet down and identify any layers of concern, and see if they are reactive in stability tests.

Overall our snowpack is strengthening. There are weak layers in our snowpack; they are becoming less reactive with time. Identify wind loaded terrain and avoid it.

Avalanche and Weather Outlook

We are entering a warm up with potential to see rain fall on a dry snowpack. See the forecast here. With the addition of rain and warmer temperatures expect the avalanche danger to increase quickly.

I will issue the next advisory on Saturday,February 03, 2018

Ski and ride safe.

The post Avalanche Advisory for February 1, 2018 appeared first on Missoula Avalanche.



This information is the sole responsibility of the Forest Service and does not apply to operating ski areas. The avalanche danger rating expires at midnight tonight but you can use the information we provide to help you make more informed decisions regarding travel in avalanche terrain for the next few days.

Our advisory area includes the Bitterroot Mountains from Lost Trail Pass North to Hoodoo Pass, the Rattlesnake Mountains and the Southern Swan and Mission Mountains near Seeley Lake. Avalanche information for the Lookout Pass/St. Regis Basin is available from the Idaho Panhandle Avalanche Center.

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[Scott]

Current West Central Montana Avalanche Advisory
Posted: Feb 03, 2018 06:19 am
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Missoula Avalanche
Avalanche Advisory for February 3, 2018

considerable danger
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The current avalanche danger is CONSIDERABLE in the west central Montana backcountry. Natural avalanches are possible, and human-triggered avalanches remain likely. Cautious route finding and conservative decision making are essential for backcountry travel today.

Good morning, this is Travis Craft with the West Central Montana Avalanche Center’s avalanche advisory for February 03, 2018. This danger rating 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 29 F to 34 F in the region. In the Bitterroot winds are 11 mph with gusts of 19 mph out of the SW. In the northern part of the advisory area, winds are reading 22 mph with gusts of 24 mph out of the SW. Snotels are not reporting this am. Most data is from midnight and before. Rain has fallen to roughly 6000 feet.

Logan and I took the sleds to the southern Missions yesterday near Seeley Lake. We found 6 new inches of snow and warming temperatures throughout the day. We observed active wind transport of snow and cornice growth. We also saw wet loose releases in the afternoon.

The main avalanche problem is wind slabs. These slabs are large and getting stressed by warming temperatures and the addition of new snow. Look for rounded pillows of snow near ridgelines and on cross-loaded slopes. Recognize signs of instability such as cracking in the surface snow. Avoid traveling on or under wind loaded slopes.

The second avalanche problem is wet loose releases. When slopes start to produce roller balls or pinwheels, it is time to move to another aspect.

The final avalanche concern is persistent slabs. There are some weak layers in the snowpack that could become reactive with the additional loading of snow or rain. Dig a pit and see how reactive these weak layers are to the new load and warming temperatures.

Overall with the addition of rain and warming temperatures the snowpack can change rapidly. Look for bullseye data today; roller balls, shooting cracks and collapsing, these will identify changing snowpack conditions. There is a lot of uncertainty in how high the rain will fall; therefore today conservative decision making is essential. Pay close attention today as conditions can change quickly in a matter of minutes to hours with rain on snow events.

Avalanche and Weather Outlook

Today rain and snow mix to 6000 feet and above possibly. These conditions will lead to increasing avalanche danger today. See the forecast here.

Ski and ride safe.

The post Avalanche Advisory for February 3, 2018 appeared first on Missoula Avalanche.

 

[Scott]

Current West Central Montana Avalanche Advisory
Posted: Feb 05, 2018 06:06 am
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Missoula Avalanche
Avalanche Warning for February 5, 2018

high danger
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An avalanche warning is in effect for the West central Montana backcountry. The current avalanche danger is HIGH. Very dangerous avalanche conditions exist. Travel in and around avalanche terrain is not recommended. Large human triggered avalanches are likely.

This is Logan King with an avalanche warning for Monday, February 5th, 2017. This avalanche warning is valid for 24 hours. The avalanche warning will either be extended or terminated at 0600 on February 6th.

This danger rating does not apply to operating ski areas and is the sole responsibility of the U.S. Forest Service.

Weather and Snowpack

Snow and rain continue to impact the region. SWE’s across the area range from .9-1.6 inches of water this morning and an additional 6-12 inches of snow have fallen over the past 24 hours. Temperatures this morning at the majority of mountain locations are above 32 degrees and did not drop below freezing overnight. Rain line is currently around 5,500-6,000 feet, and rain was reported to over 7,000 feet yesterday. Ridge top winds are 22 mph gusting to 36 mph from the WNW.

A large and heavy load of snow has been added to the northern portion of the advisory area. We received reports of up to 2 feet of new snow yesterday, strong winds and dense snow falling. Further south heavy snow and rain have about 6,000 feet have added a significant load of water that is stressing the snowpack. Continued precipitation with the potential of up to another inch of water today are further complicating avalanche conditions.

With the snow/water totals we have seen, rain to unseasonably high elevations and strong winds; avalanche conditions have significantly deteriorated. Storm slabs, wet slabs, wind slabs, persistent and deep persistent avalanches are all possibilities today. With the multitude of problems and high probability of failures today, traveling around or on avalanche terrain is not recommended.

Keep in mind that the majority of avalanche accidents happen during or immediately after a storm. The snow pack doesn’t like rapid changes and has gotten a significant load over a short period of time. Conditions will remain touchy for the next couple of days until the snow has time to settle.

Ski and ride safe.

The post Avalanche Warning for February 5, 2018 appeared first on Missoula Avalanche.

 

[Scott]

Current West Central Montana Avalanche Advisory
Posted: Feb 06, 2018 06:06 am
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Missoula Avalanche
Avalanche Advisory for February 6, 2018

considerable danger
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The avalanche warning has expired and the current avalanche danger is CONSIDERABLE for the west central Montana backcountry. Human triggered avalanches are likely in specific terrain. With dangerous avalanche conditions, cautious route-finding and conservative decisions are critical for backcountry travel today.

Good morning, this is Logan King with the West Central Montana Avalanche Center’s avalanche advisory for February 06, 2018. This danger rating 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 storm has subsided and conditions have settled down a bit. Winds are calm at 5 mph gusting to 8 mph from the WSW. Snowfall has diminished and the advisory area picked up 1-4 inches of snow last night adding an additional .1-.2 inches of SWE. Temperatures have dropped below freezing and are averaging in the upper-twenties this morning.

Travis and I rode in the Brushy Fork of the central Bitterroot yesterday while Tim toured in the Rattlesnake. Some cracking and whumphing was observed but conditions were rapidly improving yesterday. The cooler temps and dropping rain line helped the snowpack to settle and bond and conditions were noticeable more settled by mid-day.

The greatest concern today will be wind slabs. Sustained strong winds over the weekend paired with plenty of snow for transport have resulted in large windslabs above 6,000 feet. These wind slabs will easily be triggered by skiers or riders on leeward terrain and on features that have been cross loaded. Carefully evaluate the landscape to identify areas of wind loading before traveling near avalanche terrain.

The secondary concern today will be storm slabs. We found the storm slabs to be settling and bonding already yesterday and cool temps will further aid this process. Keep in mind that a large load of snow has been added over the last few days and even though it is starting to bond the new snow will be suspect for another day or so.

Persistent slabs are the final avalanche concern. The surface hoar that has been problematic is now buried pretty deep in most locations but when its found closer to the surface it continues to propagate readily in stability test. The only way to know if this layer is present is to dig pits and perform stability tests. The persistent weak layers are less likely to trigger now but if they do fail, it will result in very large avalanches. Be very mindful of the consequences of this layer failing.

Avalanche and Weather Outlook

The avalanche danger will continue to slowly decrease as the snow settles today and tomorrow before the next round of high water snow begins around Thursday. Minimal accumulations of snow will continue with light winds for the next day or two. The next storm looks to set up similarly to the last one with warm temperatures, high winds, and complex rain/snow boundaries.

Ski and ride safe.

The post Avalanche Advisory for February 6, 2018 appeared first on Missoula Avalanche.

 

[Scott]

Posted: Feb 08, 2018 06:22 am
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Missoula Avalanche
Avalanche Advisory for February 8, 2018

considerable danger
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A CONSIDERABLE avalanche danger exists on wind loaded terrain across the West Central Montana backcountry. On all other terrain the avalanche danger is MODERATE but is trending towards instability by this afternoon. Conditions will be dynamic today, continually re-evaluate conditions and terrain if you are out in the backcountry.

Good morning, this is Logan King with the West Central Montana Avalanche Center’s avalanche advisory for Thursday,February 08, 2018. This danger rating 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

Snow showers and rain continue to impact the region this morning. Over the past 24 hours 1-4 inches of snow have accumulated. Temperatures did not drop below freezing last night and rain is falling to about 5,500 feet as of 5 a.m. Water totals this morning are .5-1.1 inches from the Central Bitterroot to the northern extent of the advisory area. The Southern Bitterroot has had significantly less precipitations thus far. Winds this morning are out of the SW-WSW in the teens gusting to the upper-twenties.

Variable conditions are prevalent today and will require keen observation and evaluation. I toured near Lolo pass yesterday and found strong winds that were cross loading slopes. The wind loaded areas were touchy and shooting cracks were easy to initiate while traveling on or near wind deposits. Travis and Tim were in the Southern Swans yesterday and also found wind slabs along with signs of loose wet activity.

Wind slabs are the number one concern today. Winds were strong yesterday and have continued through the night. Large wind slabs have formed near ridges and smaller ones can be found on cross loaded terrain. Carefully look for signs of wind loading and if you observe shooting cracks or other signs of wind slabs move to a different aspect.

Mild temperatures and mixed precipitation are expected today which will lead to continued loose wet avalanche activity. Look for indicators such as roller balls to identify the surface instability and avoid terrain traps that increase the consequences of a small slide. Rain line is going to climb this morning until the cold front begins to move into the region later today. With extended rain on snow, wet slab avalanches can become problematic as the day progresses. Avoid steep terrain where the snowpack is showing signs of saturation as wet slabs are notoriously hard to predict.

Persistent slabs are the final problem that should be on your radar today. Buried surface hoar and crust have become less sensitive since the last storm cycle. Although less reactive these layers are now deeply buried, creating the potential for very large avalanches. Persistent slabs are low probability and high consequence, so avoid likely trigger points like shallow and rocky areas.

Avalanche and Weather Outlook

The forecast suggest rain to 6,000 feet across the advisory area today and dropping this afternoon leading to heavy snow into friday. Strong winds are also expected and look to shift directions as the front approaches. Conditions have the potential to change rapidly today and are largely dependent on timing. Avalanche conditions will be on the rise as precipitaion and winds increase.

Ski and ride safe.

The post Avalanche Advisory for February 8, 2018 appeared first on Missoula Avalanche.

 

[Scott]

Posted: Feb 10, 2018 06:33 am
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Missoula Avalanche
Avalanche Advisory for February 10, 2018

considerable danger
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The avalanche danger for the West Central Montana backcountry is CONSIDERABLE on wind-loaded terrain. A MODERATE avalanche danger exists on all other terrain. Large avalanches are possible in specific terrain. Careful identify areas of increased avalanche risk and utilize cautious route-finding techniques to travel in the backcountry today.

Good morning, this is Logan King with the West Central Montana Avalanche Center’s avalanche advisory for Saturday, February 10th, 2018. This danger rating 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 has finally returned to West Central Montana. Temperatures across the advisory area this morning range from 3-19 degrees. Winds are light from the NW at 12 mph gusting to 14 mph. Light snow continued through the day yesterday and last night adding another couple of inches. The snow is much lighter and colder than we have seen for the last month and only .2 inches of water were added to the snowpack since yesterday morning.

Travis and I rode up at Wisherd ridge yesterday. We found about 6-8 inches of low density snow. At lower elevations the new snow was sitting on saturated snow and runnels were observed to 6,400 feet. Above that the snow was much colder and had preserved graupel throughout the upper layers of the snowpack. Overall we found the snow that is continuing to trend towards stability with wind slabs as the glaring concern.

The greatest concern continues to be wind slabs. Strong winds did a number above about 6,000 feet. Large wind slabs have formed on lee terrain and will be susceptible to triggers from skiers and riders. Look for rounded pillows of snow, cornices, and shooting cracks that will key you into locations where wind loading has occurred. Avoid traveling on or under wind loaded terrain as these wind slabs are primed and waiting for a trigger.

Non-wind loaded terrain continues to gain strength. Loose snow avalanches are the secondary concern today. The new light snow lacks cohesion to form a slab but will easily sluff in steeper terrain. The biggest concern for these sluff avalanches are terrain traps that increase the consequences of being swept off your feet or sled. Carefully evaluate the consequences of even a small slide before committing to steep terrain.

Finally the buried surface hoar and associated crusts are now found deep in the snowpack. This means that deep persistent slabs are the third concern today. The buried surface hoar is now deep enough in the snowpack that it has become very hard to trigger, but it is a still a possibility, albeit an unlikely one. Be cautious around shallow or rocky areas as they will be the prime location to trigger slides on these deep layers.

Avalanche and Weather Outlook

A weak high pressure system looks to set up for the next 36 hours or so. Cold and settled conditions will persist through the day today before the next system moves in late Sunday into early Monday. Avalanche danger will continue to trend towards stability.

The next advisory will be issued on Tuesday, February 13th. Ski and ride safe.

The post Avalanche Advisory for February 10, 2018 appeared first on Missoula Avalanche.

 

[Scott]

Current West Central Montana Avalanche Advisory
Posted: Feb 13, 2018 06:02 am
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Missoula Avalanche
Avalanche Advisory for February 13, 2018

moderate danger
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The current avalanche danger is MODERATE on wind loaded slopes in the west central Montana backcountry; on all other slopes, the danger is LOW.Human triggered avalanches are possible. Heightened avalanche conditions exist on wind loaded terrain features. Evaluate snow and terrain carefully and identify features of concern.

Good morning, this is Travis Craft with the West Central Montana Avalanche Center’s avalanche advisory for February 13, 2018. This danger rating 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 1 F to 10 F in the region. In the Bitterroot winds are 10 mph with gusts of 17 mph out of the SW. In the northern part of the advisory area, winds are reading 23 mph with gusts of 34 mph out of the West. The forecast area received 0 to 1 inches of new snow in the last 24 hours.

Logan and I went to the Rattlesnake yesterday. Tim and Greg went to Spruce Creek in the central Bitterroot. We had a Level 1 avalanche class over the weekend at Lost Trail Pass. All of us saw small cornice failures that happened in the last loading events over the weekend. We were not able to get any propagations in our pit tests except on the buried surface hoar in a shallow snowpack near Lost Trail. Overall the snowpack is consolidating. We saw small 3 to 4-inch wind slabs that released naturally and got cracking on small wind slabs in the Rattlesnake.

The primary avalanche problem is wind slabs. The recent winds have scoured and created small to large wind slabs that are sensitive to human triggers on leeward slopes. Look for rounded pillows of snow near ridgelines and on cross-loaded slopes. Recognize signs of instability such as cracking in the surface snow.

The second avalanche problem is persistent slabs. The buried surface hoar is not very reactive in pit tests. Dig a pit to see if there are any layers of concern and how reactive they are in pit tests before committing to any steep slope. Avoid shallow rocky terrain where it is more likely to trigger these weak layers.

Overall the shifting of winds over the weekend have scoured many slopes and created small sensitive wind slabs. The weak layers in our snowpack are strengthening. Cornices have grown with the strong winds give them a wide berth. Identify wind loaded terrain and dig a pit to identify any weak layers before committing to steep slopes.

Avalanche and Weather Outlook

Expect the avalanche danger to stay the same until the storm system comes in on Wednesday. The avalanche danger will slowly increase with the storm. See the forecast here. I will issue the next advisory on Thursday, February 15th.

Ski and ride safe.



The post Avalanche Advisory for February 13, 2018 appeared first on Missoula Avalanche.

 

[Scott]

Missoula Avalanche
Avalanche Advisory for February 15, 2018

considerable danger
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The current avalanche danger is CONSIDERABLE in the west central Montana backcountry on wind loaded slopes. All other slopes the danger is MODERATE. Natural avalanches are possible, and human-triggered avalanches remain likely on wind loaded slopes. Cautious route finding and conservative decision making are essential for backcountry travel today.

Good morning, this is Travis Craft with the West Central Montana Avalanche Center’s avalanche advisory for February 15, 2018. This danger rating 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 12 mph with gusts of 24 mph out of the W. In the northern part of the advisory area, winds are reading 20 mph with gusts of 28 mph out of the West. The forecast area received 4 to 9 inches of new snow in the last 24 hours.

Logan and I went to the Rattlesnake yesterday. Tim and Greg went to Lolo Pass. Logan and I saw active wind transport and found many wind scoured slopes that the new snow will have a hard time bonding with. Greg and Tim found the new snow was bonding to the old snow surfaces. We were able to get a layer of facets 3 feet deep to propagate in a pit test.

The primary avalanche problem is wind slabs. Look for rounded pillows of snow near ridgelines and on cross-loaded slopes. Recognize signs of instability such as cracking in the surface snow. New snow has been loaded onto previously loaded slopes or scoured slopes. These freshly deposited slabs will be very sensitive to human triggers. Identify wind loaded slopes and avoid travel on or below them.

The second avalanche problem is persistent slabs. Dig a pit to see if there are any layers of concern and how reactive they are in pit tests before committing to any steep slope. Avoid shallow rocky terrain where it is more likely to trigger these weak layers. With the new load of snow the many layers in our snowpack may become reactive to human triggers. Look for bullseye data such as collapsing, shooting cracks and whumphing to help with identifying instabilities in the snowpack.

Wind slabs will be sensitive to human triggers today. Identify wind loaded slopes and avoid them. Use small test slopes with low consequences to see how the new snow is bonding to old snow surfaces. Look for bullseye data: shooting cracks, collapsing, and whumphing to help determine snow instabilities. Dig a pit 3 feet down to identify layers of concern and how reactive these layers are to the new load of snow.

Avalanche and Weather Outlook

The danger will stay the same until Friday when the next system moves in. See the forecast here. Logan will issue the advisory on Saturday.

Ski and ride safe.

The post Avalanche Advisory for February 15, 2018 appeared first on Missoula Avalanche.

 

[Scott]

Missoula Avalanche
Avalanche Advisory for February 17, 2018

considerable danger
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The avalanche danger is CONSIDERABLE for the West Central Montana backcountry. Strong winds and significant snow are creating dangerous avalanche conditions, making human-triggered avalanches likely. Careful snowpack evaluation, cautious route-finding, and conservative decision-making are essential for travel in the backcountry today.

Good morning, this is Logan King with the West Central Montana Avalanche Center’s avalanche advisory for Saturday, February 17th, 2018. This danger rating 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

A storm system has begun to impact the area. Early this morning 3-6 inches of snow has accumulated since yesterday in the northern portion of the advisory area. The southern half of the region has picked up 8-16 inches of snow this morning and up to 1.2 inches of SWE. Temperatures are in the teens to mid-twenties. The strong winds from the past couple of days have settled a bit and are currently 14 mph gusting to 26 mph from the WNW at Point 6. In the southern Bitterroot at Deer Mountain winds are 8 mph gusting to 12 mph from the S.

Yesterday Matt was up at Lolo Pass, and he found storm slabs to be a growing concern with intensifying snowfall. On Thursday observers were at Lost Trail Pass and found that wind slabs were the most significant concern. I was up on Wisherd Ridge Yesterday and encountered strong winds that were creating very touchy wind slabs.

With plenty of snow for transport and the sensitive wind slabs observed yesterday, wind slabs will be a significant avalanche concern today. During stability tests we found the wind slabs to be extremely reactive with minimal force. Small to Large wind slab avalanches will be likely on leeward terrain. Look for rounded pillows of snow near ridges and mountain tops and avoid terrain below cornices.

Storm Slabs are the other significant concern today. With over an inch of water at some mountain locations and more snow in the forecast, the potential for storm slab avalanches will be increasing through the weekend. Look for signs like shooting cracks and whumphing to indicate that the storm snow is forming a slab and stressing the snowpack. Storm slabs problems usually settle within a day or two after the storm cycle is complete, so practice some patience and err on the side of caution as the storm slab problem will be dynamic and changing throughout the extended weekend.

Persistent week layers are the third avalanche concern today. Buried surface hoar, near surface facets, and some stout crust continued to gain strength this week but should be approached with suspicion, considering the new load. The persistent weak layers are getting buried pretty deep and if they fail will produce very large avalanches in isolated areas. Take the time to dig a quick pit and perform stability tests because it is the only way to know if these layers are present and reactive.

Avalanche and Weather Outlook

The avalanche danger will be on the rise as snowfall will increase today. The weather forecast suggests intensifying snow throughout the day today with warming temperatures before an arctic airmass moves into the region late today and into tonight. As the cold air moves in, winds will shift directions and intensify further complicating avalanche conditions.

The next advisory will be issued on Tuesday, but an update will be posted if necessary as the storm continues to develop.

Ski and ride safe.

The post Avalanche Advisory for February 17, 2018 appeared first on Missoula Avalanche.

 

[Scott]

Missoula Avalanche
Avalanche Warning for February 18, 2018

high danger
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An avalanche warning is in effect for the West Central Montana backcountry. The current avalanche danger is HIGH. Very dangerous avalanche conditions exist. Travel in and around avalanche terrain is not recommended. Large human triggered avalanches are likely in many areas today.

This is Logan King with an avalanche warning for Sunday, February 18th, 2018. This avalanche warning is valid for 24 hours. The avalanche warning will either be extended or terminated at 0600 on February 19th.

This danger rating does not apply to operating ski areas and is the sole responsibility of the U.S. Forest Service.

Weather and Snowpack

Significant snow and wind continue to impact the region. Snow totals range from 8-14 inches bringing storm totals well over 2 feet in some areas thus far. The new snow has been drier than the last storm but .8-1.9 inches of SWE were added to the snowpack over the last 24 hours, over 3 inches of SWE have been seen at some mountain locations since Friday morning. Winds are currently out of the W at 12 mph and gusting to 26 mph. A period of strong wind yesterday evening brought sustained winds that were 30-40 mph accompanied by gust up to 68 mph.

Warming temperatures yesterday have resulted in an upside-down structure. The storm slab was reactive yesterday with numerous reports of soft storm slabs that released naturally. The storm snow became more reactive later in the day and will be even more sensitive today with more load.

Wind slabs were touchy earlier this week and will be under more stress with the new load and strong winds further building the slabs. Winds will change directions today, and wind slabs will be found on all aspects as the storm progresses.

Accumulating snow and building winds will lead to deteriorating conditions. A cold front will move in this morning creating lighter snow, but the load has already pushed the snowpack over the tipping point. The snowpack does not like rapid changes and will be weak for the next few days.

The post Avalanche Warning for February 18, 2018 appeared first on Missoula Avalanche.

 

[Scott]

Current West Central Montana Avalanche Advisory
Posted: Feb 19, 2018 05:58 am
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Missoula Avalanche
Avalanche Advisory for February 19, 2018

high danger
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The avalanche warning has expired, but a HIGH avalanche danger remains on wind loaded terrain. On all other terrain across the West Central Montana backcountry, the avalanche danger is CONSIDERABLE. Strong winds and significant snow have created sensitive wind slabs that will make avalanches likely on all wind loaded terrain. Careful snowpack evaluation, cautious route-finding, and conservative decision-making are essential for travel in the backcountry today.

Good morning, this is Logan King with the West Central Montana Avalanche Center’s avalanche advisory for Monday, February 19th, 2018. This danger rating 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

Snowfall has slowed across the advisory area. Overnight an additional inch or two of snow has accumulated. Temperatures this morning are below zero degrees fahrenheit. Winds are out of the E in the twenties and are gusting to the thirties.

I was up at Lolo pass yesterday and found an unsettled snowpack. The storm slab had not yet bonded to the old snow surface. Numerous natural release small storm slabs were observed on all terrain. Widespread whumphing was found on terrain where the wind had affected the storm snow and wind slabs easily propagated in stability tests.

Wind slabs are the primary concern and will be easily triggered today. Travel in terrain where wind slabs have formed is not recommended. Strong easterly winds returned to the region behind the cold front that worked its way across Western Montana yesterday. This means that wind slabs can be found on any aspect so carefully evaluate slopes before moving into avalanche terrain.

The secondary concern today will be the storm slabs. As the storm intensity drops off the storm slab problem is beginning to settle out. Storm slab avalanches are still likely, but the snow continues to gain strength. The snow will need another day or so to fully bond before the storm slab problem can be put to rest.

Deep persistent weak layers are the third avalanche concern today. The new load may have provided the additional stress needed to activate the now deeply buried layers. Given how touchy the snow has been this layer is now also susceptible to step down avalanches. If the deep persistent layers fail, the resulting avalanches will be very large so take the time to dig and see if these layers are present in the snowpack.

Avalanche and Weather Outlook

Overall the avalanche danger will remain the same through the day today. Strong easterly winds look to continue. The forecast now points towards cold temperatures and light snow showers before the storm breaks late today. The next advisory will be issued on Tuesday.

Ski and ride safe.

The post Avalanche Advisory for February 19, 2018 appeared first on Missoula Avalanche.

 

[Scott]

Current West Central Montana Avalanche Advisory
Posted: Feb 20, 2018 05:40 am
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Missoula Avalanche
Avalanche Advisory for February 20, 2018

considerable danger
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The avalanche danger is CONSIDERABLE for the West Central Montana backcountry. Wind loading has created dangerous avalanche conditions in specific areas. Careful snowpack evaluation, cautious route-finding, and conservative decision-making are essential for travel in the backcountry today.

Good morning, this is Logan King with the West Central Montana Avalanche Center’s avalanche advisory for Tuesday, February 20th, 2018. This danger rating 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 storm has abated and cold and clear conditions have settled into the region. Temperatures this morning range from -1 to -10 degrees, and in the North Fork of the Jocko are -22. Winds are currently 16 mph gusting to 20 mph from the WNW at Point 6. A trace to one inch of snow fell at isolated mountain locations last night.

I toured near Lost Trail Pass yesterday. Conditions were calm and clear. The storm slab continued to gain strength, and the wind slabs were the most prominent concern yesterday.

Large avalanches are likely in terrain that has been wind loaded and cross loaded. Avoid areas that show signs of wind loading like rounded pillows of snow or cracking/collapsing. Wind slabs continue to propagate in stability tests and have the potential to be pretty big, some of the propagations of late are up to three feet deep. Avoid traveling on or under wind loaded terrain.

There is a lot of dry surface snow that will make loose dry avalanches likely. These avalanches will be small but can be dangerous if there are terrain traps that increase consequences of getting caught. Evaluate not just the likelihood of the snow to move but the consequences before committing to steeper terrain.

The storm slab continues to gain strength but is variable in size and reactivity across the region. Carefully assess if the snow has bonded before traveling in avalanche terrain. The storm slabs have settled in many locations but there are isolated areas where a little more time is required before the new snow has fully settled.

Avalanche and Weather Outlook

A stable weather pattern looks to set up for the next few day, and cold temperatures will persist through the work week. The stable forecast will lead to continued decreasing avalanche danger.

The next advisory will be issued on Thursday, Ski and ride safe.

The post Avalanche Advisory for February 20, 2018 appeared first on Missoula Avalanche.

 

[Scott]

Current West Central Montana Avalanche Advisory
Posted: Feb 22, 2018 05:55 am
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Missoula Avalanche
Avalanche Advisory for February 22, 2018

moderate danger
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The current avalanche danger is MODERATE in the west central Montana backcountry. Human triggered avalanches are possible. Heightened avalanche conditions exist on specific terrain features. Evaluate snow and terrain carefully and identify features of concern.

Good morning, this is Travis Craft with the West Central Montana Avalanche Center’s avalanche advisory for February 22, 2018. This danger rating 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 -2 F to 10 F in the region. In the Bitterroot winds are 2 mph with gusts of 3 mph out of the SE. In the northern part of the advisory area, winds are reading 1 mph with gusts of 4 mph out of the SE. The forecast area received 0 to 1 inch of new snow in the last 24 hours.

Tim and Steve went to the Rattlesnake yesterday. Greg and Theo went to G spot near Lolo Pass. Logan and I went to Seeley Lake. Tim and Steve found the storm slabs were well bonded. Greg and Theo found the persistent weak layers to be unreactive in tests and had no bullseye data for instability either. Logan and I had mechanical failures with the snow machines and were not able to look at conditions.

The primary concern is wind slabs. Identify wind loaded terrain. Look for rounded pillows of snow near ridgelines and on cross-loaded slopes. Recognize signs of instability such as cracking in the surface snow.

The second avalanche problem is persistent slabs. Before committing to a steep slope, dig a pit 3 feet down and identify any layers of concern, and see if they are reactive in pit tests.

Overall our snowpack is strengthening. The weak layers in the snowpack are becoming less reactive in pit tests. We are not getting reports of human-triggered avalanches or naturals in the days after the storm. The instabilities in our snowpack are decreasing. Identify wind loaded terrain. Dig a pit to check for persistent weak layers before committing to any steep slope.

Avalanche and Weather Outlook

We will have some new snow over the next couple of days. See the forecast here. Look for the avalanche danger to stay the same with these light accumulations. I will issue the advisory on Saturday, February 24.

If you are out in the backcountry, please send us your observation, these are very helpful in producing the advisory.

Ski and ride safe.

The post Avalanche Advisory for February 22, 2018 appeared first on Missoula Avalanche.

 

[Scott]

Current West Central Montana Avalanche Advisory
Posted: Feb 24, 2018 06:06 am
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Missoula Avalanche
Avalanche Advisory for February 24, 2018

low danger
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The current avalanche danger is LOW for the west central Montana backcountry. Low danger does not mean no Avalanche danger. Look for high elevation wind slabs on isolated slopes. Use safe travel protocols, only exposing one person to a slope at a time.

Good morning, this is Travis Craft with the West Central Montana Avalanche Center’s avalanche advisory for February 24, 2018. This danger rating 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 7 F to 15 F in the region. In the Bitterroot winds are 3 mph with gusts of 5 mph out of the South. In the northern part of the advisory area, winds are reading 8 mph with gusts of 29 mph out of the WNW. The forecast area received 0 to 1 inch of new snow in the last 24 hours.

Logan and I went to the southern Missions yesterday with the sleds. We found a very well consolidated snowpack. We did not see any natural releases or human-triggered avalanches. We did not get any propagation in our snow pit tests. We did not get any shooting cracks from our skis on our machines. Geoff was in the Lost Trail Pass backcountry in the southern Bitterroot. He got a couple of small loose avalanches to release from ski cutting on steep North facing slopes(>38 degrees). He did not get any propagations in his pit tests. Overall our snowpack is strengthening. Low danger does not mean no danger. Ride slopes one at a time and dig a pit before committing to any steep slope.

The main avalanche problem is wind slabs. There are wind slabs above 7000 feet on isolated slopes that could be triggered by a rider. Recognize signs of instability such as cracking in the surface snow.

The second avalanche problem is persistent slabs. Before committing to a steep slope, dig a pit 3 feet down and identify any layers of concern, and see if they are reactive in pit tests.

Overall the snowpack has strengthened. There are still avalanche problems with Low danger. Do not let your guard down, practice safe travel protocols of only exposing one rider to a slope at a time and dig a pit 3 feet down to see if any weak layers are reactive. Pay attention to weather changes that can change the avalanche danger such as wind and additional loading from snow.

Avalanche and Weather Outlook

A storm system is entering our area today through Sunday. This system is forecasted to bring some additional snow today and 5-7 inches of snow on Sunday. See the forecast here. The new snow and winds will increase the avalanche danger.

If you are out in the backcountry, please send us your observation, these are very helpful in producing the advisory.

Ski and ride safe.

The post Avalanche Advisory for February 24, 2018 appeared first on Missoula Avalanche.

 

[Scott]

Current West Central Montana Avalanche Advisory
Posted: Feb 27, 2018 06:06 am
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Missoula Avalanche
Avalanche Advisory for February 27, 2018

moderate danger
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The current avalanche danger is MODERATE for the West Central Montana backcountry. Avalanches are possible in specific terrain. Evaluate snow and terrain carefully to identify locations of heightened concern.

Good morning, this is Logan King with the West Central Montana Avalanche Center’s avalanche advisory for February 27th, 2018. This danger rating 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 heavy snowfall has subsided and an additional 1-4 inches of snow accumulated overnight. Mountain temperatures this morning range from 2-14 degrees. Winds are out of the West at 19 mph gusting to 29 mph at Point 6.

Since Friday the region has received a substantial amount of new snow. The snow has been light and low density and lacks cohesion. The takeaway is that there are weak layers, but the slabs required to create avalanches of significant concern are lacking. I toured around Lolo pass yesterday, Travis and Tim were riding near Twin Lakes, Matt was teaching in the Lost Trail backcountry, and we had a mechanized level 1 at Granite Pass this weekend. There were also numerous public observations over the past few days. There has been plenty of new snow, but the observations generally indicate continued bonding and a settling snowpack with a couple of avalanche problems to look out for.

Areas where wind has been able to affected the snow and create even slightly stiffer wind slabs, will be the primary concern. There are plenty of weak layers in the extremely dry/light snowpack but they require a slab stiff enough to transfer the energy creating propagation, and ultimately slab avalanches. Look for any cohesiveness in the slab on wind loaded terrain to identify the areas of greatest concern. Winds have been variable and produced small-large wind slabs in isolated areas. Look for signs of loading on terrain features before entering avalanche terrain.

Persistent weak layers are the secondary concern today. As stated before there are weak layers in the snowpack that can be suspect if there is a slab above them. Two of the noteworthy weak layers are facets that have developed on or near the uppermost melt-freeze crust and the cold preserved snow from the last storm cycle. This problem is more widespread than the wind slabs but is harder to identify and less reactive. Take a quick minute to dig a pit and perform stability test to identify if these layers are present and have the potential to fail.

Avalanche and Weather Outlook

More settled conditions look to linger through the day today before another pulse of moisture sets up tonight and into tomorrow. Without any significant changes in the immediate future, the avalanche danger will remain the same.

If you are out in the backcountry, please send us your observation, these are very helpful in producing the advisory.

Ski and ride safe.

The post Avalanche Advisory for February 27, 2018 appeared first on Missoula Avalanche.

 

[Scott]

Current West Central Montana Avalanche Advisory
Posted: Mar 01, 2018 06:22 am
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Missoula Avalanche
Avalanche Advisory for March 1, 2018

moderate danger
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A MODERATE avalanche danger exists across the West Central Montana backcountry. Avalanches are possible in specific terrain. Carefully evaluate the snow and terrain to identify areas of heightened concern.

Good morning, this is Logan King with the West Central Montana Avalanche Center’s avalanche advisory for March 1st, 2018. This danger rating 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

Snow accumulation was minimal overnight and some areas received a trace to two inches of snow. Winds are currently from the East at 8 mph and gusting to about 20 mph at Point 6 and Mt. Sentinel. Stronger winds can be found in the Bitterroot where Deer Mountain is showing 19 mph winds gusting to 26 mph from the SSE. Mountain temperatures this morning range from 14-24 degrees.

Yesterday we toured in the Rattlesnake. We found lots of deep low-density snow and continued settling, setting up for a pretty stable snowpack. The only concerns we could identify yesterday were small wind slabs in isolated terrain and persistent weak layers that were minimally reactive.

Wind slabs are small and in isolated pockets with the potential for some larger ones near ridge lines and below cornices. Wind slabs did not propagate in stability tests but showed potential to be problematic and have been for the last few days. Look for rounded pillows of snow or unusual surface snow to identify areas where wind has deposited snow.

There is a layer of cold preserved snow from the last storm cycle and a layer of facets that have formed across the region. These layers were quiet yesterday as there was no slab above them to transfer energy. This layer may become more reactive today as warm air temperatures will rapidly change the surface snow. There is the possibility that the surface snow will gain enough cohesion as the snow warms to develop into a slab. Take a minute to dig and identify if this layer is present, and if so re-evaluate it as the day progresses, and conditions change.

Loose wet avalanches will be another growing concern today. With warming temperatures and solar radiation, surface snow activity will increase throughout the day today. Look for roller balls and loose natural releases to identify when and where this problem is developing. Remember that loose wet slides can easily be managed with terrain selection, avoid terrain traps that will increase the consequences if you are seeing increasing signs of loose wet activity.

Avalanche and Weather Outlook

A southwesterly flow will bring warmer air today. Snow showers will be possible today before temperatures drop Friday and a colder moist system sets up for the weekend. While the weather may make some layers more reactive today, overall the avalanche danger shouldn’t climb too much and will remain mostly the same.

If you are out in the backcountry, please send us your observation, these are very helpful in producing the advisory.

Ski and ride safe.

The post Avalanche Advisory for March 1, 2018 appeared first on Missoula Avalanche.

 

[Scott]

Missoula Avalanche
Avalanche Advisory for March 3, 2018

moderate danger
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The avalanche danger is MODERATE for the West Central Montana backcountry. Avalanches can be triggered in isolated locations across the region. Before traveling in avalanche terrain, carefully evaluate and identify areas of concern.

Good morning, this is Logan King with the West Central Montana Avalanche Center’s avalanche advisory for March 3rd, 2018. This danger rating 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 cold again this morning ranging from 6-11 degrees across the advisory area. Winds across the region are light at 9 mph gusting to 11 mph from the SE. No new snow was picked up overnight but a brief period of snow yesterday brought 1-4 inches to some mountain locations.

Travis and I were riding in Spruce Creek yesterday. We found the surface snow to be dense, even at upper elevations. Air and wind temps were mild until mid-day. A strong front pushed through dropping temperatures, and snow while winds increased drastically. The change was short-lived and cold clear conditions settled in overnight.

The primary avalanche concern is wind slabs above 6,000 feet. Before the surface snow got heavy, strong and shifting winds deposited snow into small pockets and near ridges. We observed multiple natural wind slab failures yesterday and have received reports of natural and human triggered wind slabs as well through the week. Wind slabs are spotty across various terrain so carefully look for identify features like drifts, rounded pillows of snow and striations in the snow surface to identify potential ares for avalanche activity. Before entering avalanche terrain thoroughly evaluate the snow to determine if it has been wind affected and has the potential to avalanche.

Wet loose avalanches at upper elevations and wet slab avalanches at lower elevations are possible. Wet avalanche problems will primarily be focused on the southern half of the compass and will increase through the afternoon today. Look for indicators like rollerballs to identify that the surface is becoming saturated to key you into when a move to cooler aspects is required.

Persistent slabs are also a concern today. Facets and cold preserved snow have created some weak layers in the snowpack and are suspect in areas where a slab is above the weak layers. These layers are widespread across the region but most locations still lack the overlying slab. Take a minute to dig a pit and identify if there is a harder layer above that will allow for slab failures.

Avalanche and Weather Outlook

Conditions will be clear today before another round of light snow sets up for tonight into Sunday morning. The avalanche danger will not change today other than the increasing wet activity as the temperatures rise through the day.

If you are out in the backcountry, please send us your observation, these are very helpful in producing the advisory.

Ski and ride safe.

The post Avalanche Advisory for March 3, 2018 appeared first on Missoula Avalanche.

 

[Scott]

Current West Central Montana Avalanche Advisory
Posted: Mar 06, 2018 06:17 am
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Missoula Avalanche
Avalanche Advisory for March 6, 2018

moderate danger
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The current avalanche danger is MODERATE in the west central Montana backcountry. Human triggered avalanches are possible. Heightened avalanche conditions exist on specific terrain features. Evaluate snow and terrain carefully and identify features of concern.

Good morning, this is Travis Craft with the West Central Montana Avalanche Center’s avalanche advisory for March 06, 2018. This danger rating 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 15 F to 21 F in the region. In the Bitterroot winds are 5 mph with gusts of 11 mph out of the SSW. In the northern part of the advisory area, winds are reading 8 mph with gusts of 15 mph out of the NNW. The forecast area received 1 to 6 inches of new snow in the last 24 hours.

Logan and I took the sleds to the Brushy Fork in the central Bitterroot yesterday. Tim went to the Rattlesnake. We all found wind loaded terrain to be the primary avalanche problem. Logan and I experienced intense snow banding yesterday. There are weak layers in our snowpack, but they were unreactive in our pit tests. We got several public observations from the weekend of similar problems. Overall our snowpack is relatively stable.

The primary avalanche problem is wind slabs. Identify wind loaded terrain. Look for rounded pillows of snow near ridgelines and on cross-loaded slopes. Recognize signs of instability such as cracking in the surface snow. It is possible to cause a slab avalanche on wind loaded terrain today.

Overall our snowpack is relatively stable. Identify wind loaded terrain. Dig a pit 3 feet deep before committing to any steep terrain(>35 degrees). Use small test slopes to see how the new snow is bonding to old snow surfaces. Cornices are very large this time of year and unpredictable in failure, give them a wide berth. Loose snow avalanches should not be a problem unless they not you down and take you into terrain trap.

Avalanche and Weather Outlook

Light snow banding today. See the forecast here. Look for the avalanche danger to stay the same with these light accumulations. I will issue the advisory on Thursday, March 08.

If you are out in the backcountry, please send us your observation, these are very helpful in producing the advisory.

Ski and ride safe.





The post Avalanche Advisory for March 6, 2018 appeared first on Missoula Avalanche.

 

[Scott]

Current West Central Montana Avalanche Advisory
Posted: Mar 08, 2018 06:07 am
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Missoula Avalanche
Avalanche Advisory for March 8, 2018

low danger
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The current avalanche danger is LOW for the west central Montana backcountry. Low danger does not mean no Avalanche danger. Use safe travel protocols, only exposing one person to a slope at a time. Look for loose wet avalanches to be the primary concern with warming temperatures below 6000 feet.

Good morning, this is Travis Craft with the West Central Montana Avalanche Center’s avalanche advisory for March 08, 2018. This danger rating 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 25 F to 32 F in the region. In the Bitterroot winds are 11mph with gusts of 17 mph out of the SW. In the northern part of the advisory area, winds are reading 9 mph with gusts of 20 mph out of the NW. The forecast area received no new snow in the last 24 hours.

Logan and I were in the Rattlesnake yesterday. Tim and Greg went to Mt. Fuji near Lolo Pass. We all found our snowpack to be relatively stable. The primary avalanche problem was loose wet avalanches on southern exposed slopes. We were not able to get any propagations in our pit tests.

The primary avalanche problem is loose wet avalanches on slopes below 6000 feet. Snotels showed that all sites froze overnight and temperatures are rising. Rollerballs will be signs of surface instabilities. If you see pinwheels, it is time to change aspects or get to higher elevations.

Overall the snowpack is well consolidated. Cornices are big right now give them a wide berth. With warming temperatures, these large cornices are weakening. Dig a pit 3 feet down before committing to any steep terrain. Use safe travel protocols, only exposing one person to a slope at a time.

Avalanche and Weather Outlook

Later today a warm wet system will move into the region. See the forecast here. This new snow will fall on a variety of old snow surfaces from sun crusts to surface hoar. Use small test slopes to see how the new snow is bonding to old snow surfaces. With the addition of fresh snow or rain below 5000 feet look for the avalanche danger to increase. Pay attention to weather changes that can change the avalanche danger such as wind and additional loading from snow.

If you are out in the backcountry, please send us your observation, these are very helpful in producing the advisory.

Ski and ride safe.



The post Avalanche Advisory for March 8, 2018 appeared first on Missoula Avalanche.

 

[Scott]

Current West Central Montana Avalanche Advisory
Posted: Mar 10, 2018 06:11 am
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Missoula Avalanche
Avalanche Advisory for March 10, 2018

considerable danger
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The avalanche danger is CONSIDERABLE for the West Central Montana backcountry on wind loaded slopes. Strong winds and significant snow are creating dangerous avalanche conditions, making human-triggered avalanches likely on leeward slopes. All other slopes the danger is MODERATE.Careful snowpack evaluation, cautious route-finding, and conservative decision-making are essential for travel in the backcountry today.

Good morning, this is Travis Craft with the West Central Montana Avalanche Center’s avalanche advisory for March 10, 2018. This danger rating 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 15 F to 21 F in the region. In the Bitterroot winds are 6 mph with gusts of 8 mph out of the SW. In the northern part of the advisory area, winds are reading 9 mph with gusts of 14 mph out of the NW. The forecast area received 6 to 12 inches of new snow in the last 24 hours.

Logan and I toured in the Rattlesnake yesterday. We found very sensitive wind slabs. The storm came into the area with considerable winds. Look for leeward slopes to have small to large wind slabs. We got shooting cracks from our skis.

The primary avalanche problem today is wind slabs. Leeward terrain was loaded yesterday. Look for shooting cracks from skis or machine to identify instabilities. Identify wind loaded terrain. Look for rounded pillows of snow near ridgelines and on cross-loaded slopes. Recognize signs of instability such as cracking in the surface snow. It is possible to cause a slab avalanche on wind loaded terrain today.

The second avalanche problem is loose wet. Rollerballs will be signs of surface instabilities. If you see pinwheels, it is time to change aspects.

Overall our snowpack is relatively stable. Identify wind loaded terrain. Dig a pit 3 feet deep before committing to any steep terrain(>35 degrees). Use small test slopes to see how the new snow is bonding to old snow surfaces. Cornices are very large this time of year and unpredictable in failure, give them a wide berth. Loose snow avalanches should not be a problem unless they knock you down and take you into a terrain trap.

Avalanche and Weather Outlook

Warm temperatures and sun for the next couple of days. See the forecast here. Wind slabs will be less sensitive to human triggers. With Freezing overnight and solar activity, look for loose wet avalanches to be the primary concern.

If you are out in the backcountry, please send us your observation, these are very helpful in producing the advisory.

Ski and ride safe.





The post Avalanche Advisory for March 10, 2018 appeared first on Missoula Avalanche.



This information is the sole responsibility of the Forest Service and does not apply to operating ski areas. The avalanche danger rating expires at midnight tonight but you can use the information we provide to help you make more informed decisions regarding travel in avalanche terrain for the next few days.

Our advisory area includes the Bitterroot Mountains from Lost Trail Pass North to Hoodoo Pass, the Rattlesnake Mountains and the Southern Swan and Mission Mountains near Seeley Lake. Avalanche information for the Lookout Pass/St. Regis Basin is available from the Idaho Panhandle Avalanche Center.