Observation: NWAC Forecaster
Basic Information
Observation Details
Observation Date:
January 7, 2023Submitted:
January 7, 2023Observer:
NWAC Forecaster - Joe DellaportaZone or Region:
Mt HoodLocation:
North side- Tilly Jane (Up to 5000 ft)Signs of Unstable Snow
Recent Avalanches?
None ObservedCracking?
IsolatedCollapsing?
None ExperiencedMedia/Attachments
Advanced Information
Weather Summary
Cloud Cover:
ObscuredTemperature:
32°FWind:
Moderate , SNew/Recent Snowfall:
HN24: 4 inchesSnowline sitting at 4500 ft. Above this dense, wet snow is falling. South winds were strong and actively drifting new snow. Visibility was poor.
Snowpack Observations
The day started in the rain at the Tilly Jane Trailhead. Snow lines were sitting at 4500 ft. Above this elevation, wet and heavy snow was falling. I observed HN24 of 10cm (4 inches) and about 25 cm (9 in) of snow sitting on the 12/30 rain crust. The snow above and below the rain crust was moist and well bonded to the 12/30 crust at this elevation.
The strong winds drifting the new snow was the main story. It was easy to find the pillow-like slabs forming on the lee sides of the ridge in the burn scar. These specific areas of wind drifted snow were on average 1’ deep and fairly reactive on test slopes. I observed multiple shooting cracks under my split in these areas. These slabs are likely larger in size and more sensitive above 6000 where the new snow is colder and drier.
Avalanche Problems
| Problem | Location | Distribution | Sensitivity | Size | Comments |
|---|---|---|---|---|---|
Wind Slab
|
|
Layer Depth/Date: 1-2 ft deep Comments: Slabs forming up to 1' thick at 5000 ft. Specific areas of wind drifted snow were reactive with test slopes producing multiple shooting cracks. |