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Observation: North Fork Park

Observation Date
1/27/2024
Observer Name
Gagne/Johnston
Region
Ogden » Ben Lomond » North Fork Park
Location Name or Route
North Fork Park
Weather
Sky
Obscured
Wind Direction
North
Wind Speed
Light
Weather Comments
Partly cloudy in the am with a lowering cloud deck in the afternoon. Winds from the north above 8,500' although no transport noted.
Snow Characteristics
New Snow Depth
2"
New Snow Density
High
Snow Surface Conditions
Dense Loose
Damp
Snow Characteristics Comments
Rain line from Wednesday evening/Thursday morning up to 7,200' with 5 cms of dense, rimed snow on top of the crust.
Despite the cloud cover - which I thought would lead to some greenhousing - the clouds kept temperatures cool enough to keep the snow dry, even at low elevations.
HS (height of snow)
120-150 cms < 7,500'
150 - 200 cms 7,500 - 8,800'
Red Flags
Red Flags
Poor Snowpack Structure
Red Flags Comments
A poor snowpack structure exists in some places, but the PWL is gaining strength with a deep snowpack.
Avalanche Problem #1
Problem
Persistent Weak Layer
Trend
Decreasing Danger
Problem #1 Comments
The PWL continues to gain strength and is 4F to 4F+ hard. No collapsing.
Snow Profile
Aspect
North
Elevation
8,200'
Comments
The snowpack is looking promising as it continues to strengthen. Pits between 8,000 and 8,500 on northerly aspects:
- on slopes that had avalanched and had a thinner snowpack, the 1m slab on top of the facets was 1F hard with 4F hard facets in the bottom 40 cms.
- on slopes with a deeper snowpack (2 meters), the slab on top of the PWL is 100-150 cms thick and 1F to Pencil hard, with 4F+ hard facets that are damp in places.
Despite the Moderate danger and signs of increasing stability, we slowly and cautiously stepped into steeper avalanche terrain (> 30° in steepness), continually evaluating the snowpack where at one point, we stopped 2/3 of the way down the slope as we saw a steep rollover that we did not want to commit to and ascended back up the slope.
The more likely place to trigger an avalanche in the PWL is in steep terrain with a thin snowpack.
Photos of
1. Rain runnels in the snow surface at lower elevations.
2. Wind-affected terrain along exposed ridgelines.
3. A branch stuck to the uphill side of a tree as the avalanche swept by, likely occurring on the January 13 cycle.
Today's Observed Danger Rating
Moderate
Tomorrows Estimated Danger Rating
Moderate
Coordinates