Field Report

Front Range - CO

2024/12/29
Lat: 40.319, Lon: -105.673
Backcountry Area: Front Range
Author: Mike Cooperstein
Organization: Forecaster, CAIC

Report Information

Observation Summary

The snowpack is variable. The dry spell in December really weakened the snowpack. Strong winds have moved a lot of snow out of the alpine and into the near treeline elevation band. This area is still lagging behind areas further to the west and needs a few good storms to rebuild the snowpack. The near treeline elevation band is the most dangerous place right now. Slopes in the near treeline elevation band facing west through north to southeast have a cohesive slab over very weak snow. Multiple snow profiles in this elevation band had propagating snowpack test results.

Area Description

Flat Top Mountain, Rocky Mountain National Park

Route Description

Bear Lake, up the Flat Top Mountain Trail, descend to the Fern Lake Trail

Snowpack

Cracking: Minor
Collapsing: None

In below treeline areas, the snowpack is mostly composed of faceted grains on all aspects. Recent snow is starting to build a cohesive slab, especially in open areas that are exposed to the wind, but at the moment, the slab isn't thick enough to propagate a fracture. The near treeline elevation band is by far the most dangerous area because there is a cohesive slab resting on very weak faceted grains formed in early December. On southeast-facing aspects, there is also a melt-freeze crust sandwiched between 2 layers of weak faceted grains. Strong southwesterly winds have drifted a lot of snow into the near treeline elevation band. Drifted areas were 250 centimeters, but it was easy to find other spots that were only 30 - 50 centimeters thick and completely composed of faceted crystals. Above treeline areas are very wind-hammered. Slopes are either stripped back to the bare ground, are impenetrable wind-packed snow, or are facets sitting on the rocks. This is not atypical for this area in December.

Weather

Overcast with light snow throughout the day. Calm winds below treeline. Strong winds from the southwest near and above treeline.

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