Field Report

Northern San Juan - CO

2025/03/05
Lat: 37.897, Lon: -107.695
Backcountry Area: Northern San Juan
Author: Jeff Davis
Organization: Forecaster, CAIC

Report Information

Observation Summary

18 inches of snow, equalling 1.4" of SWE, measured at the Red Mountain Pass study plot over the storm. Winds were strong from the west and northwest. New snow drifts near ridgelines were 30-50 cms in depth, but were fairly unreactive to ski pressure. Sun was warming the new snow quickly on sunny and low elevation slopes, creating hot pow and glop conditions.

Area Description

Red Mountain Pass

Route Description

Skied on both the east and west side of Red Mountain Pass. Commadore area and lower parts of Red 3.

Avalanches

Saw an avalanche

Loose avalanches being triggered by sun out of steep rocky terrain. All size 1 that I saw. A few storm snow avalanches triggered by new snow and wind, with the largest avalanche on an east slope near Black Bear Pass.

i
Expand to see more details
Date # Elev Asp Type Trig SizeR SizeD Problem Type Location
03/04/2025
1 <TL N SS N R1 D1 Storm Slab
03/04/2025
1 >TL E SS N R2 D2 Storm Slab

Snowpack

Cracking: None
Collapsing: None

The new snow fell on many different surfaces. I took a closer look at how the crust that developed during last weekend's warm up and how it is dealing with the new load. The crust under the new snow felt strong just under foot, but digging down it was only a few centimeters thick. Facet growth is prospering under that crust and is something we will be watching as this next round of heavy snow loads slopes. The new snow was bonding pretty well to the crust but snowpack tests showed moderate to hard failures on the facets below the crust. The 2/14 layer is still in the top meter of the snowpack and a layer to watch, but I did not get any failures in that area this go around, but not writing it off. In general, the snowpack in the Red Mountain Pass area tolerated Tuesday's cold snow but Thursday's warm storm will continue to test multiple buried weak-layers in the top meter of the snowpack.

Weather

Sun and warm in the AM. Clouds started to build around 3pm.

Observation Media Uploads