Haines Avalanche Center

Forecast as of 2018-12-08 at 09:00 pm and expires on 2018-12-10

Above 2,500ftHigh

1,500 to 2,500ftHigh

Below 1,500ftHigh

Degrees of Avalanche Danger

Avalanche Problems

Problem Details

Problem #1: Storm Snow

Heavy precipitation and southerly winds have increased the avalanche danger to high - traveling in avalanche terrain is NOT recommended. The forecasted precipitation will not bond well with the old snow surface. Look for signs of natural avalanche activity and stay out of avalanche run-out zones. With 12-18" of snow forecast tonight and more beyond that, the avalanche danger is likely to persist and produce large and deep avalanches as storm total accumulation increases.

Problem #2: Wind Slab

A strong southerly flow indicates that wind slabs that formed following the November 25-26th storm event on south through east aspects are now under even more stress - due to additional snow load. Beware that current wind speed and direction are heavily loading north through west aspects that are now susceptible to rapid transport. These slabs are likely to continue to be a problem as storm snowfall totals increase and wind deposits form a hard slab on top of weak snow.

Further details:

Snow-levels will to range between 2,000 - 3,000ft over the next couple days with the storm, and more precipitation is forecasted in the week to come. Expect rain at lower elevations and a warm temperature regime to produce complicated travel in avalanche terrain. 

Avalanche Activity

Widespread avalanche cycle began early Saturday morning with heavy precipitation, rising temperatures, and moderate to strong winds. Expect heavy new snow to produce heightened avalanche activity as it loads weak/facetted snow from the prior cold, dry spell over the November 25/26th rain crust. 

Weather

We had a very wet October and November, with snow levels about 1,000ft above average, near 3500ft. Above that level there was good accumulation, with almost nothing below it. December has started off with some drier and cooler weather that today turned wet and windy. 

   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
10" N/A  N/A 2500 moderate 12"/ 1.20 *
Flower Mountain @ treeline
24" 13" / 1.30 0" / 0.00 2500 moderate 16"/ 1.60 *
Chilkat Pass @ 3,100ft
 12" >5" / 0.50  0" / 0.00 2500 moderate, E 16"/ 1.60 *

( *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.

Alerts

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 9 AM AKST SUNDAY...