0430 temp. at 6350′ in Carnelian Bay: 29.3 deg. & 89% RH
Trace new snow
0515 temp. at 8650′ Tamarack TH: 20 deg. under flurries/light snow
4-6″ 36hr. storm total
Backcountry obs.
Overcast skies with light snow started off the morning at lake level and in the backcountry. The 2/1-2/2 storm underperformed with snow totals, but there’s enough of a refresh in the backcountry to make skiing more fun than a frog in a glass of milk!
Light to moderate SW-W winds raked the forests and ridgelines at dawn giving a subtle surface texture to the cold and light new snow. Despite its levity, the new snow still has enough texture to provide cushion and float above the old crust layer. Skinning in steep, traversing terrain provides some challenges: the poorly bonded new snow slides out on the firm crust beneath.
In wind-exposed areas, firm surfaces are forming as windward faces rime in the low clouds and high humidity. Lee zones do have growing drifts with the potential for wind slabs to enlarge modestly as more snow and wind arrive today. No instabilities like cracking, whumphing, or hollowness were noted, but skiing initiated some minor sluffing on steeper terrain.
The wind-kissed, cold pow is just enough to provide consistently soft turns. Turn too sharply and the crust becomes evident, but not problematic. The fun is back!
Weather and forecast thoughts:
Today will be mostly cloudy with some peeks of sunshine in between snow showers. Highs around the lake will stay in the low 30’s with temps in the mountains hanging in the low to mid 20’s. A few inches of accumulation are possible in town while up to 6″ could fall in the mountains, potentially more along the crest and west of CA 89.
Showers will increase in intensity this afternoon as another impulse of energy moves in off the Pacific and aligns with afternoon heating. The combination of lifting from the impulse, with added instability from daytime heating could fire off some heavier, convective showers with short-lived intense snowfall rates.
Tonight through Sat. and Sat. night snow backs off again to just some lingering showers. Temps. remain cold with highs in the low 30’s to 20’s depending on elevation, with low’s into the teens and 20’s.
Sunday the big show gets going. The much advertised “biggest storm of the season” looks to take shape and dump its heavy load on the Sierra from Sun. daybreak through early Tues. An impactful storm is likely with the ability to close roads and create a snowpack at all elevations in the Tahoe Basin. Just how much is still in flux.
As of this morning, models show a strong low combining cold air, dynamic lift, and a robust tap of subtropical moisture moving into the area on Sunday, dumping the heaviest snow Sun. through Mon. AM. An intense plume of moisture looks to arrive from the south and shuffle north during the morning on Sunday. The flow within the fire hose – from the SW – will align well with the topography of the Sierra to create enhanced lift and heavy snow. Highest amounts will be along the crest, but the system will also create efficient spillover into NV and points east.
Today’s model runs trimmed snowfall amounts back a bit for Tahoe and bumped them up for the Eastside to our south, as the plume will likely originate over the Central/Southern Sierra, move north, hang out, then begin moving back to the south before breaking apart into more intermittent snow. Probabilistic models show a 50-60% of 12″+ for Tahoe communities, with 60-80% of 2-3’+ along the Sierra crest. Totals jump up to 4’+ for the crest in Mono County, with 2’+ likely for Mammoth and June Lakes.
Each storm is unique and this one could meet those marks or even overperform. However, considering the trend of models overpromising this season, these amounts may be trimmed back in future forecasts or during the actual event. Time and the atmosphere will tell.
Moving beyond Monday, the active, cold pattern continues with showery, intermittent snow Tues. and Weds., potentially picking up again with another storm arriving from the NW around Thurs. Keep it coming…
Hey winter, it’s good to see you.