Island Park

We rode around the north and south sides of Mt Jefferson, and Yale Creek. The danger has definitely dropped and the snowpack has stabilized a lot since I was last here on New Year's Eve when we experienced big thunderous collapses. The peak instability was around the first week of January. We could see evidence of just a few slides from that time. All the snowfall during that time made conditions dangerous then....but stable now. Since Xmas eve, this area has received snow containing 4.5-6.5 inche of water.

Today we didn't see any recent avalanches. We didn't experience any collapsing or cracking. We had stubborn stability tests with columns that took a lot of hard hits to break even where the snowpack was thinner.

I'm not ready to climb up steep chutes on Jefferson, but I'm feeling really comfortable in many other areas - especially places with a 5-6 ft deep snowpack.

Winds were moving a little snow. One wind slab/drift produced a shooting crack but we couldn't get any others to crack.

18 inches of powder at the East Fork Divide. Overall, found about 4 feet of snow. Rocks lurking slightly under the snow surface in some areas. Base was pretty solid - a surprise. There is a faceted layer at the bottom but the snowpack was pretty consolidated and fun to ride with good traction. Did not see any fissures or cracks in slope and dust feel any collapsing slabs during the ride.  

The GNFAC weather station at the top of Sawtelle provides wind, temperature and relative humidity information for forecasting (when it's not covered in a foot of rime ice. Photo: GNFAC

Photo: GNFAC

From the top of Sawtelle. Photo: GNFAC

We spent the last two days in the Centennials. On Wednesday, we rode up to the vehicle shop, into Yale drainage, over to Hellroaring, and across the backside to the East Hotel Creek overlook. On Thursday, we went to our weather stations for repairs and visualized much of the range from the top of Sawtelle. 

Day one focused on snowpack analysis as it was lightly snowing for most of the day S- -1 with 2-3" of accumulation throughout the day, and we did not have much for long-distance visibility. We triggered two collapses in a creek bed when someone (I) was stuck while riding toward East Hotel. We were able to see the smaller avalanche paths along Yale and the only slide was a R1, D1 cornice collapse. We dug on a north-facing slope at the pass over to Hellroaring Creek. The facet layer of concern is now buried a meter deep (4F+ hardness) with an ECTX on this layer. Total HS of 155 cm. We got ECTNs 14-29 on the three rain crust layers formed during the last storm cycle.

The south-facing pit overlooking East Hotel was a bit shallower, 125 cm HS. ECTP30 on a crust facet combo mid-snowpack and an extra-curricular ECTP31 on the facets that we have been primarily discussing this season. 

On day two, we got up high, overlooked many avalanche paths, and saw only the slide that Randy Gravett (Rescue Randy) had previously reported in Mt. Jefferson Bowl. 

The collapse and the snowpack structure indicate the potential of triggering an avalanche, but the likelihood has gone down. Given the depth of the weak layers, I am not confident that the snowpack assessment will provide full and accurate information. If folks are starting to push into avalanche terrain, my emphasis is to stick to paths that are less likely to avalanche (sheltered from the wind and less steep) and paths that have lower consequences (smaller slopes with clean runouts). As always, safe travel practices. 

If people don't want to mess with the uncertainty of avalanche terrain right now, conditions are fantastic on many slopes less than 30 degrees.