| Trigger | Natural | Remote Trigger | Unknown |
| Avalanche Type | Hard Slab | Aspect | Unknown |
| Elevation | unknown | Slope Angle | 35deg |
| Crown Depth | 3ft | Width | 200ft |
| Vertical Run | 800ft |
Avalanche: Chugach State Park
Location: North Bowl, South Fork ER
APU Snow Science class toured to Hunter Pass and North Bowl to make observations about the Valentine Week’s storms impact on the Front Range. This was quite a popular spot today with Seward highway & Hatcher Pass avalanche closures.
Avalanche Details
Several natural avalanches had run on both sides of the valley within the last 24 (-48?) hours. Most impressive ones were on two
E facing gullies of Rendezvous ridge that had run all the way to the treeline. Also notable wind slab release on NW ridge up Harp Mountain (R1-D1.5) that ran quite far down the bowl.
Weather
Skies obscured most of the day, broken by ~2pm.
Temps below freezing the whole day.
Winds variable, but mostly light w gust of moderate from south.
Precip: very light snow on and off with one bout of graupel. Not much accumulation during the day.
Snow surface
We were pleasantly suprised by the colder snow surface than we were expecting.
~5-10cm of soft new snow on the surface depending on location.
Above and near treeline varied surface conditions included glare raincrust, soft windpacked snow and 20cm high sastrugi.
Snowpack
We were expecting more reactive new/old snow interface, especially with wind slab, and were curious about lower snowpack persistent layers, but our test results showed fair stability. We dug four pits at Hunter Pass (N aspect, 2750', 22-25deg slope) and none of the test results were super reactive. HS varied 110-125 with one pit dug on super loaded spot w HS 235 cm. There was 40cm slab, but the weak layer (10cm of facets ~80cm down) was not failing nor propagating.
Several gullies on Rendezvous Ridge had ran all the way to treeline.
Recent wind slab crown on NW ridge of Harp Mountain. Ran far down the bowl.
Visibility was on/off today and new snow was being actively transported on ridge lines.
General snowpack structure. Surprisingly blah test results.