X
Avalanche Danger Rose: this graphic represents an avalanche forecaster's idea of how the avalanche danger exists across the topography in a given region. It is not a map...it is an idea. Picture it as a cone-shaped mountain viewed from above, built of three elevation bands; the outer ring represents low elevations, the middle ring represents middle elevations, and the innermost circle represents high elevations. Each elevation band is divided into sectors that represent the slope aspect (N-NE-E-SE-S-SW-W-NW). Each sector\'s color represents the avalanche danger rating assigned that day (see Avalanche Danger Scale).

In this example, the Avalanche Danger Rose depicts an avalanche danger rating of considerable on all high elevation aspects and on north to west-facing mid elevations; all other sectors possess moderate avalanche danger. The illustration depicts the spatial distribution of this forecast across a landscape.
X Loose Wet: Loose wet avalanches release at a point and spread downhill in a conical fashion. They occur where water is running through the snowpack, and release at or below the trigger point. They can be deadly on steep and/or treed slopes and around terrain traps such as cliffs and gullies.
X
X
Avalanche Problem Rose: this graphic represents an avalanche forecaster's idea of the distribution of a particular avalanche problem across the topography in a given region. Picture it as a cone-shaped mountain viewed from above, built of three elevation bands; the outer ring represents low elevations, the middle ring represents middle elevations, and the innermost circle represents high elevations. Each elevation band is divided into sectors that represent the slope aspect (N-NE-E-SE-S-SW-W-NW). Sectors colored grey are thought to have the identified avalanche problem while white sectors do not.

In this example, the Avalanche Problem Rose indicates that a particular avalanche concern exists on all high elevation aspects and on north to west-facing mid elevations and that this concern is far less likely to be encountered on other aspects and elevations.
X Chance of Avalanches: This graphic depicts how likely you are to trigger avalanches or encounter natural avalanches while traveling on avalanche prone slopes. Unlikely means that few avalanches could be triggered in avalanche terrain and natural avalanches are not expected. The chance of triggering or observing avalanches increases as we move up the scale. Certain means that humans will be able to trigger avalanches on many slopes, and natural avalanches should be expected.
X Size of Avalanches: This graphic depicts the potential size and destructive force of expected avalanches. Small avalanches are not large enough to bury humans and are relatively harmless unless they carry people over cliffs or through trees or rocks. Moving up the scale, avalanches become large enough to bury, injure, or kill people, large enough to bury or destroy vehicles and break a few trees, and large enough to destroy railway cars, buildings, or a substantial amount of forest. Historic avalanches are massive events capable of destroying villages and gouging or altering the landscape.
X

LOW: Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.

X

MODERATE: Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.

X

CONSIDERABLE: Dangerous avalanche conditions. Careful snowpack evaluation, cautious route-finding and conservative decision-making essential.

X

HIGH: Very dangerous avalanche conditions. Travel in avalanche terrain is not recommended.

X

EXTREME: Avoid all avalanche terrain.

Current Advisory
Thursday March 23, 2017 7:30 am by Ben VandenBos

All Zones | Sawtooth Mountains | Smoky & Boulder Mountains | Wood River Valley | Soldier Mountains

Sawtooth Mountains

Bottom Line: The danger will rise to MODERATE on E-S-W aspects as the sun weakens the snow. Intense sun and above freezing temperatures make natural and human triggered avalanches possible, particularly later in the day. On shady aspects at all elevations, the avalanche danger is LOW. Triggering wind slabs on upper elevation slopes is unlikely but remains possible.

Primary Avalanche Problem

Loose Wet   

Aspect/Elevation   

Certain
Unlikely

Chance of Avalanches   

Historic
Small

Size of Avalanches   

This morning, mountain temperatures are anywhere from 5-10 degrees F below freezing. Last night’s clear skies allowed the snow surface to solidly refreeze. At lower elevations, temperatures are only slightly below freezing and this refreeze was not as substantial. As the snow heats up today, these surface crusts will begin to break down. Clear skies and light winds won’t do much to slow this melting and the danger of loose wet avalanches will increase throughout the day. As the sun moves across the sky, the danger will follow it around the compass from E-S-W. These avalanches will come in two forms, depending on elevation and snowpack structure:

1. At upper elevations where recent snowfall is sitting on top of a firm wind or sun crust, these avalanches will be relatively thin and will only involve the recent snow. You are most likely to get in trouble with these slides if you are skiing in steep, rocky terrain on sunny aspects. Even a small amount of wet snow moving down the slope can easily take you for a ride against your will. Be aware of the terrain below you and of the consequences of being carried through it. You should also be conscious of the fact that these avalanches may be releasing naturally as the day progresses, and you should have your eyes trained on the terrain above you as well. If you are seeing rollerballs and pinwheels forming and the snow is getting wet and sticky, it would be advisable to move to a cooler, shady slope.

2. At middle and lower elevations, you are more likely to see deeper loose wet avalanches involving older, slushy snow. These avalanches will be less likely but much more destructive than the smaller slides at upper elevations. Small loose wet avalanches coming down from above could possibly gouge into the slushy snow down lower and trigger a much larger slide. These deeper slides may also be triggered by collapsing cornices.

Additional Discussion: At upper elevations, small, thin wind slabs formed beneath ridgelines two nights ago. These slabs are generally bonding well with the old snow surface, but it remains possible to trigger one in very steep, upper elevation terrain where they are sitting on a slick wind or sun crust. These slabs should be relatively easy to identify and avoid. The new snow has also increased the size of cornices, which have grown impressively large this year. Many are dozens of feet tall and protrude far out from ridgelines. It’s nearly impossible to predict how far back onto ridges cornices can break - walking on rocks when traveling along ridgelines is really your only safe bet to eliminate this hazard from the equation.

Weather Forecast

Last Night
5PM - 5AM

Today
5AM - 5PM

Tonight
5PM - 5AM

Temperature

26 F 42 F 23 F

Cloud Cover

Partly Cloudy Clear Clear

Ridgetop Wind Speed

Light Light Light

Wind Direction

NW N NW

Snowfall

24hr: 0" 12hr: 0"
0" 0"

Avalanche Notes

Enter text...

Mountain Weather Summary

Yesterday was a glorious day in the mountains. Light winds blew out of the southwest for much of the day, and mountain high temperatures climbed into the mid-30’s to low 40’s F. Partly cloudy skies provided intermittent shade throughout the day with a thicker swath of high clouds moving into the area in the evening. These clouds were pushed out overnight as a weak ridge of high pressure built in the region. This morning, skies are clear to partly cloudy.

Today, as the ridge of high pressure continues to build, we can expect to see a few clouds this morning and then clear skies throughout the remainder of the day. Mountain high temperatures will reach the mid-30’s to low 40’s F, though it may feel a bit warmer thanks to calmer winds. These light winds will be blowing out of the north and will be slightly stronger in the Wood River Valley and Soldier Mountains. Light winds and clear skies are a good recipe for setting up a temperature inversion. If one develops, mountain temperatures tonight will cool only a few degrees from today’s highs. The next round of moisture is projected to move into the region later in the day Friday and should bring a few inches of fresh snow to the mountains.

Sawtooth Mountains

Last Night
5PM - 5AM

Today
5AM - 5PM

Tonight
5PM - 5AM

Temperature

26 F 42 F 23 F

Cloud Cover

Partly Cloudy Clear Clear

Ridgetop Wind Speed

Light Light Light

Wind Direction

NW N NW

Snowfall

24hr: 0" 12hr: 0"
0" 0"

Smoky & Boulder Mountains

Last Night
5PM - 5AM

Today
5AM - 5PM

Tonight
5PM - 5AM

Temperature

19 F 31 F 25 F

Cloud Cover

Partly Cloudy Clear Clear

Ridgetop Wind Speed

Light Light Light

Wind Direction

NW N N

Snowfall

24hr: 0" 12hr: 0"
0" 0"
           

Wood River Valley

Last Night
5PM - 5AM

Today
5AM - 5PM

Tonight
5PM - 5AM

Temperature

24 F 38 F 29 F

Cloud Cover

Partly Cloudy Clear Clear

Ridgetop Wind Speed

Moderate Light Light

Wind Direction

NW N NW

Snowfall

24hr: 0" 12hr: 0"
0" 0"
   

Soldier Mountains

Last Night
5PM - 5AM

Today
5AM - 5PM

Tonight
5PM - 5AM

Temperature

21 F 33 F 30 F

Cloud Cover

Partly Cloudy Clear Clear

Ridgetop Wind Speed

Moderate Light Light

Wind Direction

NW N N

Snowfall

24hr: 0" 12hr: 0"
0" 0"
           

General Information