This is an archived forecast related to a fatality on that day Issued on:Thu, Feb 20, 2025 at 4:30 PM Saturday, Feb 22 Above and Near Treeline: 3 - Considerable Below Treeline: 2 - Moderate New snow with variable wind on Friday won't increase the danger, but you can trigger a smaller slide where it drifts onto leeward slopes. These drifted spots will be scattered around as the winds shift. Don't let this new concern distract you from the fact that there are lots of places you can trigger a big avalanche. An intense winter storm dropped 3 feet or more of snow in the past week. Westerly winds drifted this snow into slabs on many aspects and elevations, but upper-elevation easterly-facing slopes are the most dangerous. Avalanches breaking below the storm snow will be large enough to bury and kill you. A growing number of recent slides propagated around terrain features or stepped down to deeper weak layers, and became nearly unsurvivable. Multiple people can ride a slope before it slides and you may not get any warning signs beforehand. Look for and avoid steep drifted slopes below ridges, in gullies, or behind convex rollovers. If you see cracks in front of you in the snow or hear audible collapses, avoid steep slopes. Make conservative terrain choices and avoid traveling on or below slopes steeper than about 30 degrees. Avalanche Problems (2) Problem: Persistent Slab Aspect/Elevation: W-N-E all elevations, SE near and above treeline, S-SW above treeline Likelihood: Possible Size: 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. Problem: Wind Slab Aspect/Elevation: All aspects near and above treeline Likelihood: Likely Size: Small to Large What you need to know about these avalanches: Wind Slab avalanches release naturally during wind events and can be triggered for up to a week after a wind event. They form in lee and cross-loaded terrain features. Avoid them by sticking to wind sheltered or wind scoured areas. Northern Mountains Regional Discussion Most areas remain at CONSIDERABLE (3 of 5) danger as the final pulse of the Valentine's Day storm cycle brings more snow to the mountains Thursday evening into Friday. There are a lot of places you can trigger a big, deadly avalanche. The most dangerous slopes are upper-elevation northeast, east, and southeast-facing drifted slopes. Observers report a growing number of avalanches propagating across entire terrain features, growing nearly unsurvivable in size. Lower elevation wind-sheltered slopes will be safer but use caution in large open areas and steep chutes where you find a drifted slab of snow over softer storm snow. This last pulse of the prolonged storm cycle ends with a closed low crossing the state and upsloping winds. Where exactly this low tracks directly affects which eastern Front Range areas see the most snow. For now, it looks like the southern Front Range will see the most and there is a new zone that shows this trend. However, check back in the morning as the systems can be unpredictable and the exact size and shape of the new zone might change. The most dangerous area continues to be the large zones that extends from the Wyoming border south through Cameron Pass, Berthoud Pass, and into the Vail and Summit County areas. The Flat Top Mountains are most similar to this area. Observers report a growing number of very large (D3) avalanches here, some naturally triggered and others from avalanche mitigation work. The Valentine's Day storm cycle dropped about 3 to 4 feet of new snow across the Northern Mountains and observers are reporting a crust-facet combination on sunny slopes and softer, faceted snow on shaded slopes below the storm snow in these zones. If you trigger a slide at this interface, it will probably be large enough to bury or kill you and could grow larger, especially if it steps down to weak snow close to the ground. The most likely place you’ll find a slide breaking even deeper are areas that previously slid this season or areas that had less than 4 or 5 feet of snow on the ground before the storm. The best way to reduce your risk is to avoid being on or under slopes steeper than 30 degrees. If you go wandering around in steep terrain, you could undoubtedly stumble across a trigger point and bring a whole mountainside down. Wide margins for error continue to be the name of the game. In the Park Range and east of the Continental Divide in Rocky Mountain National Park and the Indian Peaks and James Peak Wildernesses, avalanches in the most recent snow are the main concern. The most recent reports from this area are of slides breaking about 1 to 2 feet deep on layers within the storm snow. Upsloping winds and an additional 8 to 12 inches of snow along the Front Range keeps the danger at CONSIDERABLE (3 of 5) for Friday. It doesn’t look like the Park Range gets more than about 6 inches of snow with this storm, so the danger there stays at MODERATE (2 of 5). Winds don’t look exceptionally impressive at this time, so new issues might be more of a loose than a slab problem. So while you might not see massive valley-crushing avalanches here, don’t let your guard down quite yet; you can still trigger a slide big enough to injure or kill you. Sunny, warm weather over the weekend will hopefully help the snowpack to stabilize a bit and start a more widespread downward trend of the avalanche danger.