Tahoe Backcountry Snow

4:30am temp. at 6350′ in Carnelian Bay: 24.1 deg. with 89% RH

5:20am temp. at 7100′ TH in Ward Canyon: 12 deg.

Backcountry Snow Obs.:

I headed out on a tour this morning into the Ward Canyon backcountry on Tahoe’s west shore to get a sense of how the last storm came in on the crest.

Around 10 in. of new snow greeted us at the 7100′. Amounts increased up to nearly 14 in. of new snow up to the crest at 8500′. Snow character was low density, light and dry. Some snags and small trees are still poking through lower down. The earlier warm storms that dropped cement higher up in the Rose area dropped mainly rain in this area, so there is not nearly the base that other higher elevation areas currently have.

The snow skied well, but I skied mindfully keeping my tips up in the deep powder to not tag a shark. Our group also skied conservatively avoiding avalanche terrain. Yesterday parties triggered a few slides that appeared to fail on the buried persistent weak layer (PWL) lurking just below this last storm’s layer. We did observe one slide below treeline that failed on the pre-storm melt/freeze crust and the new snow on an ENE rollover into a gully. The crown wrapped a couple hundred feet across the feature and ran a few hundred feet into the gully. The party triggering the slide submitted an ob. on the Sierra Avalanche Center page.

The snow’s great, but the white monster lurks beneath.

Forecast Thoughts:

NWS Reno hoisted a Winter Storm Warning for the area for Saturday into Sunday for the next storm. We’ve been burned so far this season, but the forecast for this one seems to hold together. It also looks to be a cold storm with light dry pow throughout the event and some decent winds as well. Winds will start out of the SW, then turn around to the NW and N, so this is something to look out for in terms of loading on features and aspects that are less often associated with wind slabs.

I’m hoping for 8-10 in. at the house at 6350′ and 1-2 ft. out in the backcountry, with highest amounts on the west side of the lake above 7000′ and along the crest. Even with these amounts, the light character of the snow probably won’t open a ton of new terrain lower down below 7000′–there’s just not much of a base for it to fall on. However, maybe the grinding effect of snow grains blowing around on the ground will increase the new snow density a bit to fill in areas that don’t have a ton of snow. All in all, this one should bring more zones into play and help spread out the crowds.

Looking beyond the weekend storm, things look to remain relatively cool and unstable going into next week. More storms appear in the long range forecast for the middle/end of next week, along with another shot of colder air. Any snow that falls will be light and dry, but amounts and timing are still tough to discern.

Looking out into the Pacific, next week models show a large ridge of high pressure building from the mid latitudes of the eastern Pacific up into the Gulf of Alaska sending the jet northward, then crashing south along the west coast. This is likely going to keep funneling cold air down from the north into our area. This isn’t a scenario that tends to tap into subtropical moisture for big storms, but it could keep things cold and fluffy. Just gotta wait and see how things develop.

4:30am temp. at 6350′ in Carnelian Bay: 24.3 deg.

New snow: 3.5 in.

5:30am temp. at 8600′ Tamarack Peak TH: 16 deg.

New snow observed in the Tamarack BC: 3-7 in.

Backcountry Obs.

Tahoe finally got some measurable snowfall for the first time in at least a few weeks, even though in a big year, this storm would barely be noticeable. Snow started last night around 6:30pm and continued through the night. This morning the main band of snow has departed and left light flurries/snow showers in its wake with mostly cloudy skies in the Tahoe Basin. As predicted, points on the western side of the basin and along the crest received the most snow.

This morning I intended to finally ski something different and opted for Incline Peak. But after noticing how little snow appeared to have fallen in that area, I pushed on to Tamarack Peak. I found 3 inches or so had accumulated near the trailhead with some wind sculpting on the surface. All previous tracks from weeks of heavy use have been buffed and filled into a virgin surface. Higher up near the summit, 6-7 in. seemed to have fallen, but exact amounts were tough to measure due to wind affect. Moderate SW winds increased in intensity as I climbed and light snow fell during my whole tour.

The descent was excellent, likely feeling even better due to the weeks of anticipation of any snow surface that wasn’t crust, rocks and stumps. Exposed ridges and bowls did have some wind effect/slight stiffness, but the trees skied soft, fluffy and fast: fast pow!

I observed no obvious stability red flags like whumping or shooting cracks. There was a fair amount of wind transport onto N-E exposed slopes and I did see some growing wind slabs. Along the far east ridge of Tamarack a hand pit revealed a growing slab around 6 in. deep. Stomps and ski cuts did not produce results.

Forecast Thoughts:

The long-hinted at colder and active pattern seems to be upon us. NWS Reno has been consistent in their outlook for the weekend storm putting down the most snow of the season at all elevations–still not saying much. However, a solid foot on the crest and in the backcountry might have 50% or better odds. Lake level would likely be half that. I’m not getting too excited as the models have seemed more tepid than the official forecast shows. Need to wait and see.

A small inside slider type disturbance will precede the weekend storm and could give a dandruffing to the area at best.

Further out, another storm shows up for early/middle of next week and more every few days thereafter. Models do show quite a bit of variation on the storms that are further out, so this is keeping confidence in snow amounts low. Some look much like what we’ve been getting, others show some big boys around the middle of the month. However, there is consistency in that the GFS and Euro ensembles do show an active pattern.

I’ll take whatever we can get.

10pm temp. At 6350’ in Carnelian Bay: 28.2 deg. & 84% RH

No info from the backcountry today.

Forecast/current weather thoughts:

It finally feels like winter is here with consistently colder temperatures since Saturday. Lows in the twenties and highs in the upper thirties to maybe 40 for only a few hours. Now if we can just get some precipitation…

Models continue to be shaky in the long term, but continue showing something affecting Tahoe every few days or so. The next storm comes tomorrow night through early am Thursday. Both the GFS and Euro are consistently betting on a solid few inches to a foot or so in the Tahoe Sierra with snow at all elevations.

Additional snowfall looks to come around the weekend, but confidence in that system’s strength is low. Could do the cutoff dance again.

So far this season it feels like the cutoff low has reigned which makes predictability tough. Getting a system with a strong jet phasing with subtropical moisture and a North Pacific low just seems impossible. Such a difference from last season.

Either way, the next few days hold hope for more snow, so I eagerly await the outcome.