Wind will form fresh slabs at upper elevations while cooler temperatures will continue to freeze the upper snowpack. You can trigger avalanches in freshly wind-drifted slabs and there's a chance for wet avalanches on sun-exposed slopes. Be ready to make your own assessment of deeper weak layers if you go into the eastern portion of the zone.
Strong east wind will form fresh drifts during the day. Watch for blowing snow to indicate where the danger exists. Steer around convexities on slopes over 35 degrees on wind-exposed slopes. The best way to avoid triggering wind slab avalanches is to stick to wind-sheltered terrain.
(3/29/2025)
Skiers triggered shallow wind slab avalanches on the 29th at upper elevations.
Photo: NCH
Shallow wet slides could occur in recent snow as the sun warms snow surfaces. Deeper wet avalanches occurred early in the week, but surface freezes should put an end to these more dangerous avalanches. If you find areas where recently formed crusts are breaking down, watch for larger, wet avalanches running in older snow. Pay attention to overhead terrain and avoid lingering below cornices and steep, rocky slopes that could shed large chunks of snow.
If you're venturing into upper elevations east of the Cascade crest, take time to dig and look for potential weak layers in the top 3-4 feet of the snowpack. When in doubt, choose more conservative, simpler terrain.
There is uncertainty surrounding older, weaker layers of snow. Upper elevations and areas far east of the Cascade crest may not have stout crusts overlying older weak layers. There may still be a chance of triggering persistent slab avalanches east of Mazama and Harts Pass, where a shallower, weaker snowpack structure exists.
On Sunday, you could encounter very shallow fresh wind slabs at upper elevations. Strong easterly winds could drift the shallow recent snow accumulations. Otherwise, colder temperatures help the rest of the snowpack freeze and gain strength.
On Wednesday, WSDOT forecasters in the Highway 20 corridor reported a widespread cycle of wet avalanches. The cycle likely started on the 24th and continued at least through the afternoon of the 26th. Many wet slides ran on a range of slopes, and some deeper slab avalanches were reported up to D3. As shown in the video above, they confirmed that the natural cycle was still ongoing on Wednesday.
Before warming and rain, the January Drought Layer was buried 2–3.5 ft and shallower east of Mazama. Near Rainy and Easy Passes, the JDL was over 4 feet deep and capped with a thick melt-freeze crust. On March 17, an observer near Tiffany Mountain reported widely propagating recent natural avalanches and rolling collapses on a weak layer in the middle to lower half of the snowpack. As observations have become limited, our uncertainty about the snowpack has become greater.
On February 28th, a snowmobiler was killed in an avalanche near Harts Pass. You can read NWAC's report on this accident HERE.
Submit an observation to the website or the Avy App to help NWAC Forecasters reduce uncertainty. It can be short, simple, and even anonymous.
