Issued: Sat, Jan 13, 2018 at 7AM

Expires: Sun, Jan 14, 2018

 

FREE Avalanche Rescue Workshop TODAY! at Hatcher Pass, Gold Mint Lot, 11am. Practice with the pros! Click here for more info.

Mark your calendars for the Hatcher Pass Avalanche Center Annual Fundraiser and Cabin Fever Reliever, Saturday, February 10th at the Moose Lodge in Palmer. You won’t want to miss it. More info coming soon.

If you see an avalanche or have observations to share, please submit your findings to the community based observation platform HERE or email us at info@hpavalanche.org

Above 3,500ft Considerable

2,500 to 3,500ft Moderate

Below 2,500ft Low

Degrees of Avalanche Danger ?

1. Low
2. Moderate
3. Considerable
4. High
5. Extreme

Avalanche Danger Rose ?

Avalanche Problems ?

Problem Details

BOTTOM LINE

Both the avalanche hazard and the complexity of the avalanche hazard will rise throughout the day and into tomorrow with winds.

The avalanche hazard will rise today to Considerable Hazard for Wind Slab avalanches on leeward aspects today. Small natural avalanches will be possible, and small to large human triggered avalanches will be likely.

Moderate avalanche hazard exists for human triggered, small to medium, Loose Dry avalanches.

Moderate avalanche hazard exists for small to large Persistent Slab avalanches today. Buried persistent weak layers in the mid-snowpack will be stubborn to human trigger and  large enough to bury, injure and/or kill.

 


WIND SLAB AVALANCHE PROBLEM

 

The hazard will rise to Considerable Hazard at upper elevations and moderate at mid elevations by the end of the day for 1+ foot deep Wind Slab avalanches on leeward aspects. ESE winds have increased overnight transporting 4-8″ of low density powder and weak near surface faceted snow into wind slabs at mid to upper elevations, on leeward aspects, mostly West to North, on slopes 35° and steeper, which will be sensitive to human triggers.  Overnight, the Marmot weather station at 4500′ has reported ESE gusts reaching 35 mph and average wind speeds capable of transporting snow. Today’s forecasted winds above 3000′ for Hatcher Pass are ESE 24-26 mph, gusting to 35 mph, continuing through the evening with ESE 17-25 mph, gusting 34 mph. Winds should relax Sunday through Monday.

 

PERSISTENT SLAB AVALANCHE PROBLEM

A Moderate Hazard for persistent slabs today.

Last week’s problems are this week’s problems. Widespread, buried, weak layers in the snowpack are 1-4 feet deep, on all aspects, at mid to upper elevations, and are capable of producing large avalanches up to D2 in size, on slopes 35º and steeper. We are seeing these weak layers slowly strengthen over time, however today’s winds will potentially overload these buried weak layers making human triggered persistent slab avalanches possible. Persistent Slabs will be stubborn to trigger. More likely locations for triggering this type of avalanche problem are on leeward aspects, generally West to Northwest, which will become wind loaded today. They may be triggered from above, adjacent to, or from below. Avoid slopes with terrain traps that will compound your exposure to any persistent slab avalanche hazard. See this observation of a remotely human triggered avalanche occurring above Lonesome Mine on January 8th which is a good example of the dragon we are still dealing with.

Ski/snowboard cutting and snowmachine cuts are NOT good testing techniques for persistent slab avalanche problems. This type of avalanche problem is identified by digging into the older layers of the snowpack and conducting instability tests. A band of weaker snow under more cohesive snow is visible in most every pit. We suggest ECT and PST tests. No single pit will give you the green light, but one may give you the red light, alerting you to a significant problem to avoid.

Audible collapsing and shooting cracks indicate a ripe avalanche problem and areas that should be avoided. Because predicting these types of avalanches is difficult, adding insurance is prudent by maintaining excellent safe travel techniques, with only one person on slope at a time, wearing beacons on your body, carrying probes and shovels, using proper spacing, safe zones and spotters, considering radios for more effective long distance communication, and being practiced and prepared for companion rescue. Today’s FREE avalanche rescue workshop kicks off at 11am in the Goldmint Lot.

DRY LOOSE AVALANCHE PROBLEM

A Moderate Hazard for dry loose avalanches today. Low density new snow sitting on weak near surface facets will be possible to human trigger on all aspects, on slopes 40º and steeper, at mid to upper elevations and will be D1 or less in size, and low to moderate volume. Sluffs will have the ability to sweep you off your feet and compound the risk by carrying you into or over terrain traps and other hazards. Low danger exists at low elevation. Low danger does not mean no danger.

 

Ski/snowboard cuts and snowmachine cuts can effectively and safely be conducted to test and clean out this problem on your slope of choice to recreate.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The snowpack depth is highly variable, 1 to 4 feet.

IF YOU SEE AN AVALANCHE or have an observation to share, please submit your findings to the community observation platform HERE! or email us at info@hpavalanche.org

Pit profile here

Recent Avalanche Activity

1/8 – The only avalanche reported this week ( near Arkose ridgeline, a good example of the persistent slab avalanche problem we are STILL dealing with. – MORE HERE

 

 

 

 

 

 

 

 

 

 

1/12 Marmot with old wind texture showing through new snow cover 1/12

 

 

 

 

 

 

 

 

 

 

1/12

 

 

 

 

 

 

 

 

 

 

1/12 Loose dry on the Lodge Run, Marmot

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1/12 Minor sluffing in ski tracks on Microdot!

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Recent Weather

This week’s weather at 3550′:

Temps averaged 19ºF, with a low of 8ºF and a high of 28ºF.

2 inches of new snow and .2 inches of water (SWE) was recorded at IM snotel this week, although ground truth reveals about 4 inches of new snow.

Overnight at 3550′:

Temperature averaged 30° F.

0″ new snow overnight.

This week’s weather at 4500′:

Temps averaged 18ºF, with a low of 7ºF and a high of 27ºF.

Winds averaged SE 7 mph, max SE 19 mph . Gusts averaged E 12, max gusts E 28 mph.

Overnight at 4500′:

Temps averaged  26ºF overnight.

Winds averaged E 12 mph overnight, with a max gust of ESE 35 mph.


NWS recreational forecast for Hatcher Pass here


NWS point forecast here


State Parks snow report here

Additional Info & Media

Expect the avalanche hazard to rise throughout the day and into tomorrow with sustained winds building wind slabs and potentially overloading buried persistent weak layers on leeward aspects.

Today’s forecasted winds above 3000′ for Hatcher Pass are ESE 24-26 mph, gusting to 35 mph, continuing through the evening with ESE 17-25 mph, gusting 34 mph. Winds should relax Sunday through Monday.

 

Posted in HPAC Forecasts.
Jed Workman

Forecaster: Jed Workman