Avalanche Advisory Archive Pre-2016

Date Issued:2016-01-30
Danger:1
Trend:1
Probability:1
Size:1
Problem:9
Discussion:

The National Weather Service Forecasts-

TODAY...MOSTLY CLOUDY. PATCHY FOG IN THE MORNING. HIGHS AROUND 38. LIGHT WINDS.

TONIGHT...MOSTLY CLOUDY. PATCHY FOG. LOWS AROUND 30. LIGHT WINDS.

SUNDAY...PARTLY CLOUDY. PATCHY FOG IN THE MORNING. HIGHS AROUND 35. NORTH WIND 10 MPH.

SUNDAY NIGHT...MOSTLY CLEAR. PATCHY FOG. LOWS AROUND 24.
NORTHEAST WIND 10 TO 15 MPH.

After lasts week long spell of warm temps and high volumes of rain that settled and consolidated the snowpack it started to dry out and cool off yesterday giving the snowpack some time to lock back up.

Mt Roberts dropped 5+f degrees yesterday and is below freezing at 30f for the first time in a week.

Eaglecrest also cooled with the summit showing 28, mid mountain 20 and 34 at the base.

Winds are calm at this time and we have received no precip in the last 24 hours.

With no precip in the forecast for today, more cooling into tonight and tomorrow Avalanche Danger is LOW at this time. Natural avalanches are unlikely as are human triggered avalanches.

Be aware that in areas with glide we still have glide avalanche potential.

Tip:

Glide
Fracture is the process of crack propagation. When fracture occurs in a layer of snow underneath a slab sitting on a steep slope, a slab avalanche will occur.

Glide avalanches:
Glide occurs when the entire snowpack slowly slides as a unit on the ground, similar to a glacier. Don't mistake glide for the catastrophic release of a slab avalanche that breaks to the ground. Glide is a slow process, that usually occurs over several days. Glide occurs because melt water lubricates the ground and allows the overlying snowpack to slowly \"glide\" downhill. Usually, they don't ever produce an avalanche but occasionally they release catastrophically as a glide avalanche. So the presence of glide cracks in the snow do not necessarily mean danger. It's often difficult for a person to trigger a glide avalanche but at the same time it's not smart to be mucking around on top of them and especially not smart to camp under them.

We tend to find them in wet climates and when they occur in dry climates they do so in spring when water percolated through the snow or sometimes during mid winter thaws.

When do they come down? Like an icefall, they come down randomly in time--when they're good and ready--not before. You would think that they would come down during the heat of the day or when melt water running along the ground reaches its maximum. But oddly enough, they tend to release just as often with the arrival of cold temperatures following melting as during melting itself. It's hard to play a trend with glide avalanches. They come down when they're good and ready and it's impossible to tell when that is. Just don't spend much time underneath them.