Hatcher Pass

Forecast Expired - 12/16/2018

Above 3,500ft Considerable

2,500 to 3,500ft Considerable

Below 2,500ftLow

Degrees of Avalanche Danger

Avalanche Activity

Sunday had many human triggered and remotely triggered avalanches. See observations HERE for more information. 

Below: Hatcher Common, crown profile from remotely triggered avalanche burying two people on Sunday, 12/9/2018

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Above: Skier approaches old, remotely triggered avalanche from Sunday, 12/9/2018 on Hatch Common.

This avalanche failed on buried surface hoar and basal facets.

 

On Monday, forecasters were able to remotely trigger a D2 avalanche below them as they walked along a safe ridgeline, see more information HERE.

Reports have continued to come in this week indicating whumphing and cracking, bulls-eye clues for snow instability.

Weather

This week’s weather at 3550′:

Temps averaged 16ºF, with a low of 2ºF and a high of 33ºF.

IM reported about 12″ of new snow with 1″ SWE.

Overnight at 3550′:

Temps averaged 19°F.

3″ new snow.

This week’s weather at 4500′:

Temps averaged 14ºF, with a low of -3ºF and a high of 29ºF.

Winds averaged SE 7 mph, max 29 mph . Gusts averaged SE 13 mph, max gust ESE 47 mph.

Overnight at 4500′:

Temps averaged  14ºF overnight, with a Low of 9ºF .

Winds averaged ESE 11 mph overnight. Max gust SE 26 mph.


NWS Rec Forecast HERE


State Parks Snow Report HERE

Additional Information

TREND

The avalanche hazard should remain the same as persistent weak layers in the snowpack will continue to be reactive and slow to heal. Instability will continue to spike any time the snowpack is rapidly loaded with new snow or wind-transported snow loading.

Wind speeds this morning at 4500´have steadily increased. If this trend continues through today and this weekend, expect the avalanche hazard to quickly rise.

Alerts

BOTTOM LINE

Dangerous avalanche conditions continue at HP.  Human triggered avalanches large enough to bury a person will remain possible to likely through this weekend and this week. Unfortunately this season’s snowpack is set up for avalanches, and will be extremely slow to heal or improve. 

The avalanche danger is CONSIDERABLE at mid to upper elevations on all aspects on slopes 35º and steeper. Slab avalanches will fail 2-4 feet deep, at or near the ground, on weak, sugary snow. These avalanches may be triggered remotely from any adjacent terrain or the flats below.

Whumphing and shooting cracks are bulls-eye clues that conditions are ripe for avalanches. A highly variable snowpack depth exists, 1-4 feet deep, with the deepest snow in wind loaded areas, and thin coverage in many areas.