Northern New Mexico

An Avalanche Warning will stay in place today through 5pm. Heavy snowfall over the last week and recent strong winds have created very dangerous avalanche conditions. You can very easily trigger a large and destructive avalanche.  Storm slab avalanches could break on the old snow/new snow interface and be 4 plus feet deep and able to break widely across the slope or step down into deeper weak layers in the snowpack.  Persistent slab avalanches are likely on weak layers near the ground or in the middle of the snowpack that would create very large avalanches.  

Traveling in and around avalanche terrain is not recommended. Avoid being on or underneath slopes steeper than 30 degrees giving avalanche path runouts wide berths as we could see very large natural avalanches running long distances into the flats and valley bottoms below.  

Over the last week, we've picked up snow every day from a series of Atmospheric River (AR) events that have brought 40 + inches of snow and about 4.7 - 5" of snow water equivalent (SWE).  Outside of a couple of light snow showers this afternoon, snow has come to an end but moderate to strong winds will continue to blow throughout the day.  Winds won't be as strong as we saw yesterday which brought an 86 mph gust to Kachina Peak but will continue to gust in the 40 to 50 mph range.  

Yesterday, it was hard to tell if the snow was falling from the sky and what was being transported by the strong winds, but in either case, snow was moving and loading slopes, especially at upper elevations.  The strong winds and dense heavier snow with the second AR event have led to a mostly upside-down set-up within the storm snow. Stiffer, firmer snow on the surface rests on top of lower-density snow from earlier in the week. Most of the snow.  With such strong winds, you may encounter more loading than you might expect further down the slopes.

Storm slabs could be 4 to 6 feet deep on the leeward sides of ridgelines and cross-loaded terrain features at upper elevations. With the potential for more wind loading today, we could still see natural avalanches, but human-triggered avalanches are very likely at upper elevations.  Triggering a storm slab avalanche could be large on its own, but could also step down into deeper weak layers.  This one-two punch could produce very large and unsurvivable avalanches, If you are feeling the need to get out, be sure to give avalanche path runout zones wide berths as we could see avalanches running well into the flats below.  

The persistent weak layers near the ground that has plagued us much of the season are facing a significant test from the wet heavy snow, and most likely will struggle to handle this significant loading event. SWE totals over the last week from the two AR events are at 5 - 6" . For context, we had less than 5" of SWE for the water year on January 1st at the Snotel Powderhorn site. This has been a significant amount of loading as the SWE from the last week of storms accounts for a little under a third of the water we've received this year.    Near and below treeline terrain is where depth hoar near the ground continues to linger and remain reactive in a relatively shallow snowpack (< 1.5 m) prior to last week's storm.  At upper elevations, there's still a threat of triggering an avalanche near the ground, but most slopes have a deeper snowpack where impacting these layers would be more difficult but not impossible with such a significant amount of loading. In the middle of the snowpack, small-grained facets sandwiched between harder slabs and faceted crusts have been observed but are not widespread.  Most of these layers have been found on north and easterly aspects near and above treeline.  These storms over a week period will be the biggest snowfall events of the season and may push us to a tipping point where we see deep persistent slab avalanches releasing naturally.