Persistent Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Possible
- Size
- 1–2
Recent Avalanches: A small avalanche was triggered by a person on the east side of Fresno on Sunday, 3/22, at about 3,000'. On Tuesday, 3/24, observers noted natural avalanches on west to southwest-facing slopes of Lone Star and Templeton. We're unclear on the exact timing of these naturals.
Most avalanches we've seen in the past week have been on the smaller side, but can still prove problematic in steep or consequential terrain. Fortunately, signs point to a snowpack healing in the wake of our most recent snowfall last week. That said, the last storm that impacted our area fell on a very weak, faceted surface, which has left us dealing with a persistent slab avalanche problem. These are slow to heal and notorious for allowing multiple tracks on a slope before sliding.
This tends to be the time of year when we start looking toward bigger and more remote objectives in our winter pursuits. However, with a persistent slab problem, it's hard to have an 'open season' mindset. If you're choosing to move into bigger, more consequential terrain today, stack the deck in your favor by looking for clean runouts and practicing safe travel habits on both the ascent and the descent. It's equally as likely to trigger a persistent slab avalanche setting a skin track as it is descending a slope.
Loose Avalanches: The calendar says we should be considering wet loose avalanches, but the thermometer suggests we're more likely to experience dry loose avalanches again today. Unseasonably cool temperatures look to keep the surface snow cold for at least another day. Sluffs continue to run fast and are gaining volume, particularly in steep, northerly terrain above 2,500. However, if you begin to see or initiate roller balls on southerly slopes late in the day, at any elevation, these could be enough to trigger a persistent slab avalanche, as discussed above.
Natural avalanche on Butch Mtn first observed on Monday, 3/23.