Haines Avalanche Center

Forecast as of 2018-11-30 at 08:00 am and expires on 2018-12-02

Above 2,500ftModerate

1,500 to 2,500ftLow

Below 1,500ftLow

Degrees of Avalanche Danger

Avalanche Problems

Problem Details

Problem #1: Wind Slab

New snow from the 25th-26th (about 30cm deep above 3500ft) has had some time to settle and bond, but it still sits on a layer of weak facets over an ice crust. This new/old snow interface will be the main concern this weekend. 

Keep an eye out for any slabby/wind affected surface slabs. Treat any wind loaded slopes 30-degrees and steeper as suspect. Cautious ski cuts, slope tests, and snowpit tests will be very helpful to judge the bonding strength on these upper layers. Just remember that conditions change quite a bit from slope to slope, and you need to be gathering data from many slopes through the day before trusting your life to these conditions. Be conservative, and avoid steep/exposed terrain right now. Human-triggered avalanches are quite possible.

Further details:

Above 3500ft, snow depths generally range from 30-130cm. In the deeper areas, we have a well-bonded midpack frozen solidly to the ground. It hasn't been terribly cold so far this year, so facetting between rain crusts has been minor so far. One exception is in high wind-swept areas where the snow is only about 30cm deep. In these areas, there are weak 2-3mm  facets at the ground. 

Avalanche Activity

There was a widespread avalanche cycle on Nov. 26th, as the last storm warmed up bringing rain-on-snow up to 4500ft. D2-D3 Wet slabs occurred on all aspects above 3500ft. Crown depths were around 30cm, with the failure layer being weak/facetted snow sitting on our previous rain crust.

Weather

We had a very wet October, with snow levels about 1,000ft above average, near 3500ft. Above that level there was good accumulation, with almost nothing below it. This trend has continued into November.  

   Snow Depth [in] Last 24-hr Snow/SWE [in] Last 3-days Snow/SWE [in]  Today's Freezing Level [ft]  Today's Winds Next 24-hr Snow/SWE
Mount Ripinsky @ treeline
8" 0" / 0.00 0" / 0.00 0 calm 0"/ 0.00 *
Flower Mountain @ treeline
 11" 0" / 0.00 0" / 0.00 0 calm 0"/ 0.00 *
Chilkat Pass @ 3,100ft
 5" 0" / 0.00  0" / 0.00 0 calm 0"/ 0.00 *

( *star means meteorological estimate )

Additional Information

If you get out riding, please send in an observation!

Start the season with fresh batteries in your beacon, and do a rescue practice with your partners. Always carry a beacon, shovel, and probe, and KNOW HOW TO USE THEM.

Practice good risk management, which means only expose one person at a time to slopes 30 degrees and steeper, make group communication and unanimous decision making a priority, and choose your terrain wisely: eliminating unnecessary exposure and planning out your safe zones and escape routes.