| Trigger | Natural | Remote Trigger | Unknown |
| Avalanche Type | Soft Slab | Aspect | East |
| Elevation | 3800ft | Slope Angle | unknown |
| Crown Depth | unknown | Width | 1500ft |
| Vertical Run | 1500ft |
Avalanche: Summit
Location: Manitoba
Route:
Manitoba to 3400’
Avalanche Details
We think this avalanche - pictured below - occurred around 3 pm in the bowl to the east of Fresno peak, during a period of fairly intense snow transport. Despite propagating across nearly the entire bowl - granted well below ridgeline - the debris was fairly limited (~D2... maybe D2.5), making us suspect this wasn’t nearly as deep as the slides from late last week. We didn’t see tracks near the ridge to the south, so suspect it to be a natural.
Obvious signs of instability
| Recent Avalanches? | Yes |
| Collapsing (Whumphing)? | Yes |
| Cracking (Shooting cracks)? | Yes |
Observer Comments
Red flags:
Recent avalanche activity: yes, as reported in that ob.
Collapsing: yes, one that propagated a ways down the NW ridge that runs to the summit
Cracking: Yes, localized along the NW ridgeline, with cracks shooting ~20’ in the recently wind deposited snow.
Blowing Snow... Oh yeah! Light snow transport and wind affect on slopes above treeline, with tracks filling in from moderate snow transport above 3300’ and along the NW ridgeline that leads to the summit. Moderate to intense snow transport observed on neighboring peaks throughout the day.
Weather
Broken -> few clouds as the day progressed
Temps teens down low and single digits up high.
Light N winds occasionally gusting moderate above treeline, with the exception of some mid-afternoon sustained moderate N winds right at the NW ridgeline below the summit. Winds appeared to die down by late afternoon.
Snow surface
Despite wind activity, the surface remained fist hard at all locations on our tour except just on the ridgeline, where small areas of soft slab up to 18” deep were deposited. Ski penetration of 3-6” - less up high - and boot penetration of 12-24”
Snowpack
No formal stability tests.
Avalanche suspected today around 3 pm on Fresno - see notes in observation.
Mid afternoon snow transport off spirit walker
Snow transport looking south towards summit lake
Crowns from slides that took place late last week - most of roaring ridge went, with some additional activity above it on moose!
Crown from late last week in the W bowl of moose
Surface conditions looking down Manitoba.