Saturday, January 21, 2017

Sunset West Glades - I21 Closed Again

This Wednesday - January 18 through Thursday - January 19, another energetic storm precipitated from 30 to 40 cms of snow in the Boise Mountains. Idaho 21 from Idaho City to Mores Creek Summit was closed again this week from Thursday through Friday.
Idaho 21 road status for Friday, January 20th
Apparently, limited human and equipment resources are hampering Idaho Department of Transportation (IDT) to promptly reopen I21 after this winter significant snow precipitation events. These closures are negatively impacting winter recreation activities in the mountains above Idaho City.
Snowmobile transiting I21 inside the closed section.
Recreation at Mores Creek Summit is currently a lower priority for IDT, and the focus is restoring vehicular traffic between Lowman and Idaho City, in order to provide access to Lowman residents to essential services.

Perhaps, IDT should consider closing I21 road at Whoop Um Up Park N' Ski area to allow snowmobilers and skiers to access Pilot Peak recreation area. Another option is to close the road at Mores Creek Summit. A less ideal option is to close the road after the 12-mile creek pull-out area. Any of these three options are better than the current closing location at milepost 48, between Bad Bear and Hayfork campgrounds. The current road closure location is simply too low in elevation - 4900 feet.
I21 current road closure location at 4900 feet, between Bad Bear and Hayfork campgrounds.
Last Saturday we climbed to Freeman Peak from I-21 at milepost 48, the point at which the road was closed. Check the blog post Great Skiing at Freeman during Idaho21 Closure.

Today we skinned up via Sunset Peak's western ridge. The ridge gradually climbs to the north from Hayfork campground. We used the Hayfork campground bridge to cross Mores Creek.
Somewhat brushy terrain above Hayfork Campground.
The skiing was great above 5400 feet, with over 30 cm of soft powder. Below 5400 feet 10-15 cms of medium density snow covered a supportable rain crust layer.

At 6200 feet we confirmed that last week surface hoar was preserved and buried under 40 cm of new snow. We triggered several whumpfs (e.g., snowpack collapses) between 5600 and 6400 feet. We did not observe surface crack.

The next three pictures show the fragile surface hoar layer at the 40 cm depth. The last picture of this set shows the surface hoar crystals we harvested from the buried weak layer.
Not surprisingly this layer showed a propensity to propagate failures. The large 5-10 mm surface hoar crystals (picture above) make the weak layer very fragile and reactive even under soft slab conditions.

The next video shows how a shovel compression results in a sudden collapse failure in an extended column.

Standard compression tests produced moderate fracture failures results - CTMQ1(SC). Moderate compression test results require that we evaluate skiing and travel terrain selection based on the premise of how the snowpack structure might change such that moderate results are instead easy results. Or what snowpack/weather/terrain changes are necessary to make the snowpack more reactive. For instance, the surface hoar instability is likely to worsen and become easier to trigger at slopes with buried surface hoar above a solar radiation crust, or location experiencing wind loading, or new snow precipitation, or rain, or warm temps.

We did not observe surface signs of a "natural" slab avalanche cycle during the Wednesday-Thursday storm. That was unexpected. The surface hoar currently buried at 40 cm is very concerning. This surface hoar weak layer is likely to be widespread based on our observations for Mores Creek Summit, as well as Banner Summit. New snow predicted for the next few days will bury this layer deeper in the snowpack, significantly increasing the avalanche consequences, and possibly making slab avalanches unsurvivable even at relatively small slopes. It is also important to remember that slab avalanches with surface hoar weak layers tend to break at shallower angles (28-32 degrees). This is a good time for conservative decisions!

The next two picture show the terrain we ski toured last Saturday. The high point is Freeman Peak summit.
Freeman Peak views from the East.
Freeman Peak views from the East.
The terrain we ski toured from Hayfork campground provides spectacular views of the Freeman area. However, it was less than ideal for skiing. Even with the current snowpack above average, there is still significant brush from 5000 to 5600 feet elevation, and the tree forest tend to be denser that the nearby Freeman and Pilot Peak areas.
Sunset West Ridge - Having lunch at a saddle above 6000 feet.

Sunday, January 15, 2017

Great Skiing at Freeman during Idaho21 Closure

Saturday morning, the road up to Mores Creek Summit remained closed. The road has been closed from Wednesday through Saturday. According to Idaho Department of Transportation, due to Avalanche danger and reduced visibility.
I21 Closed on Saturday, January 14 - Fourth Day of Closure
It has been unusual for the I-21 stretch north of Idaho City to remain closed for four consecutive days, particularly due to avalanche danger. Furthermore, it is hard to comprehend the extended delay in opening the road considering that the weather has been clear and sunny on Thursday and Friday, allowing to at least clear I-21 up to Mores Creek Summit, and enable recreationist to access Pilot Peak Recreation Area.

I-21 was closed past 10 Mile Creek Campground. Fortunately, from the closure point, Freeman's Peak south ridge can be used to get into higher elevation terrain, which we did yesterday.

The next video showcases the riding we did yesterday, Saturday, January 14 at Freeman Peak. I feel sorry for many of the folks that missed yesterday backcountry skiing due to the road closure.

FreemanSouthRidgeJan2017 from Santiago Rodriguez on Vimeo.

Much later in the day when we returned to our vehicle, the road was open. We do not know at what time I-21 was opened. During the day, we only saw one party of skiers that followed our tracks, and a handful of snowmobilers in the distance.

We ski toured "prime avalanche terrain", but observed very limited indications of avalanches regardless of aspect and elevation. This was in conflict with the extended closure and I21 and the reasons provided to the public to justify its closure.

Stability tests fail to provide evidence of instability and no persistent weak layers were identified. A snowpit at an elevation of 7200 and Easterly aspect provided compression test results in the hard (CTH) range with poor fracture planes (Q3-Borken) at 40 and 60 cm depths. The 40 cm interface consisted of an unreactive structure of rounded facets above a melt-freeze crust. The 60 cm interface consisted of graupel above a finger hard round crystals layer.
One of the occasional crowns observed.
The riding conditions at North, North-easterly aspects and Westerly aspects were great, with a thick layer of near surface facets  (NSF) covered by surface hoar. Below a series of photos of the surface hoar crystals observed at all elevations and aspects.
Slopes with easterly through south aspects had a solar radiation crust covered by surface hoar. This will be of great concern if the surface hoar is not destroyed prior to a precipitation event. If the surface hoar is buried on top of a crust, it will enhance both the slab propagation and its ability to slide once it fails.

The solar radiation crust at Easterly/Southerly aspects was present at all elevations, and make skiing tricky. We carefully selected terrain to avoid the crust, and maximize hero skiing conditions.
North aspect remain frozen, with up to 25 cm of NSF that made skiing very noise and produced fun dry sluffs during skiing.
North Aspects remain in a deep freeze!
At the end, we skied to I21, few miles above the closure point. As we walked back we again failed to identify signs of an avalanche cycle. Below a selection pictures of roads cuts at different aspects that reliably provide backcountry skiers with signs of instability. Notice the lack of slab releases that might be associated with significant avalanche danger that could justify a road closure from Idaho City to Mores Creek Summit.
The IDT crew serving I-21 between Idaho City and Edna Creek deserves to be applauded for the many years of service. For two decades I have witnessed their dedication to providing SAFE access to Mores Creek Summit. Their work has greatly improved the safety of motorists and winter recreationists.

However, the recently extended closure, as well as the erosion of attention to road pull-outs during this winter, appears to be different from their impeccable track record. I do not need to remind our state and federal public servants that Mores Creek Summit is one of the most important winter recreation areas in South Western Idaho and essential for the vitality of Idaho City business during the winter months.

Thursday, January 12, 2017

Epic Storms - January 9-11th 2017

This week series of storms took us on rolling coaster ride with many ups and downs; from rain to snow and back to snow, from two days of epic skiing at Bogus having fun brought to a halt due to power outages that shut down the resort two different days, and Idaho 21 closed due to avalanche danger above Idaho City.
Idaho 511 road report
For many of us, it was heartbreaking not being able to make it to Mores Creek Summit (MCS). The road above Idaho City was closed. Up to the point when this post was posted, the road remains closed according to the Idaho Transp[ortation department website.

So, with no road access to MCS, it was logical to hit the slopes at Bogus Basin. Skiing was fantastic on Tuesday and Wednesday, until on both days almost at the same time, around noon, the power went out. Auxiliary power was used to get skiers out of chair lifts but the mountain was closed for skiing. BUMMER!
Bogus Basin announcement to the public about power  outages in the Ski Resort.
The amounts of snow received are striking for Bogus, as it can be seen in the Bogus Basin SNOTEL report included below;
Storms added 15 cm of SWE to Bogus Basin snowpack and more half a meter of snow.
A carefully review the SNOTEL data shows the high variability of densities of the precipitated snow due to winds and temperature variations. The next chart shows the snow height at Bogus Basin SNOTEL with selected densities calculated for 6 hour periods.

The skiing at Bogus Tuesday morning can only be described as EPIC! Snow with 7% density capping a progressive early storm layer of 11.6% density, made riding fast and smooth. On my first turn that stormy morning while dropping from War Eagle cat track into a untracked run produced my first massive face shot of the season. At that moment I knew it was going to be AWSOME! When I was stuck in the chairlift for 15 minutes or so, I did not know about the power outage. Once they start running the lifts on auxiliary power, at the top ski patrollers were communicating the heartbreaking news.

Snow continued to fall after the resort closed on Tuesday. Wednesday skiing was deep, big boards were a most. Wednesday skiing was tricky due to the upside down conditions. It was important to stay afloat and avoid getting trapped in the deeper lighter snow. As it can be seen in the chart above, there were two layers of lower density snow sandwiched with higher density. But it would not matter. After close to two of hours of skiing, the resort experienced it second power outage of the week.

MCS SNOTEL shows also a significant gain, with approximately 2 meters of snow at the pass.

Soon I21 north of Idaho City should be opening,  and we will get to ski MCS, and share pics of conditions, and identify avalanches that might have affected the roadway, as well as an idea of what backcountry skiing runs released during the storms.

UPDATE: Friday, January 13, 2017
As of this Friday morning, IDT 511 web-based report for Idaho 21 north of Idaho City indicates that it remains closed. In other words, there is no access to Mores Creek Summit. This is very unusual for this roadway segment.

The Idaho Statesman also reported on the impacted of I21 closure Idaho 21 closure cuts off access to skiing, snowshoeing, snowmobiling near Idaho City.