Vail & Summit County Archived Advisory - Expired! Avalanche Warning Issued: Thursday, February 4, 2021 at 6:00 AM Expires: Friday, February 5, 2021 at 7:00 AM There is an Avalanche Warning for the Vail/Summit County, Sawatch, Aspen, and Gunnison zones. A foot or more of new snow and strong winds have combined to overload our fragile snowpack. Large, wide, and deadly avalanches will be very easy to trigger. Natural avalanches can run long distances. Backcountry travelers should stay off of, and out from underneath slopes steeper than 30 degrees. Backcountry Avalanche Forecast Thu, Feb 4, 2021 at 6:47 AM Issued by: Kreston Rohrig Thursday Above and Near Treeline: High (4) Very dangerous avalanche conditions. Travel in avalanche terrain not recommended. Below Treeline: Considerable (3) Dangerous avalanche conditions. Cautious route-finding and conservative decision-making essential. Summary Very dangerous avalanche conditions. Avoid traveling in or around avalanche terrain today. Up to a foot of new snow from Vail to Breckenridge, down to Hoosier Pass combined with westerly winds, will overwhelm a fragile snowpack. Wind-drifted slopes facing north to east to southeast near and above treeline are the most likely places to trigger a large and deadly avalanche. Under these conditions, avalanches can fail naturally and break wider or run farther than you might expect. Sticking to low angle slopes well clear of steeper slopes above is the only way to stay safe. Avalanche Problem Persistent Slab N -> E -> SE All Elevations Very Likely Large to Very Large What You Need to Know About These Avalanches Persistent Slab avalanches can be triggered days to weeks after the last storm. They often propagate across and beyond terrain features that would otherwise confine Wind and Storm Slab avalanches. In some cases they can be triggered remotely, from low-angle terrain or adjacent slopes. Give yourself a wide safety buffer to address the uncertainty. Avalanche Problem Storm Slab All Aspects All Elevations Likely Small to Large What You Need to Know About These Avalanches Storm Slab avalanches release naturally during snow storms and can be triggered for a few days after a storm. They often release at or below the trigger point. They exist throughout the terrain. Avoid them by waiting for the storm snow to stabilize. Forecast Discussion Thu, Feb 4, 2021 at 7:30 AM Issued by: Kreston Rohrig Statewide Weather Forecast Avalanche conditions have become very dangerous across many portions of the Northern Mountains and will continue to worsen as another storm heads our way tomorrow. This is one of the biggest dumps we've seen so far, as two-day totals could push upwards of 20 inches. With a little help from westerly winds, expect to see large natural avalanches ripping out on higher elevation slopes. A wide swath of terrain picked up 10 to 12 inches of snow last night, spanning from Vail to Hoosier Pass up towards Berthoud and over to Rabbit Ears. As the storm snow settles out, it may be easy to trigger smaller slides on steeper slopes, but the real concern is avalanches breaking deeper into weak snow layers. This storm will add an inch or two of weight to a terribly fragile structure. The fear is that this will produce avalanches that break across terrain features and potentially wipe out the entire season's snowpack. These are not manageable avalanche conditions, and avoidance is the only way to stay safe. One of the best sayings out there is: "when avalanches are the problem, terrain is the solution." Well, avalanches are certainly going to be the problem, so avoiding avalanche terrain is the only tool to ensure your safety. With high uncertainty in how big avalanches could break, give any steep slope plenty of room and stay well clear of runout zones. On a somber note, the avalanche accident on February 1st in the San Juan Mountains reminds us that the season’s snowpack is problematic across the state. Persistent weak layers are especially nasty this year and will continue to haunt us for the foreseeable future. Our deepest condolences go out to the victim's friends and family.