Tahoe Backcountry Snow

0430 temp. at 6350′ in Carnelian Bay: 32.7 deg.

No new precip.

0515 temp. at 8650′ Tamarack TH: 28 deg.

Trace new snow

Backcountry Obs.

Low clouds, fog, and occasional rain/snow showers have started out the morning. At dawn in the Tamarack backcountry it snowed lightly and intermittently, accompanied by moderate winds out of the WNW.

Snow is still soft, holding up best on true N-NE aspects and in W-E facing trees. Yesterday’s fluffy, fast snow topped with surface hoar has morphed into thicker and lightly wind-effected 4-5″ of cold, soft snow, excellent for skiing fast and hopping around the forest. Lower on the mountain and on more southerly aspects, crunchy, refrozen tree melt has fallen and refrozen atop the snow surface in forested areas. True S aspects host a thin, breakable suncrust that is apparent, but not too widespread or bothersome to manage.

Moderate winds are lightly grooming the snow surface, but plenty of tracks remain visible. Apart from some subtle texture, especially near and above treeline, wind effect has been minimal at degrading the snow surface. Snow is available to transport, but pillows and wind slabs are not yet prominent, nor were actively growing on my tour.

The next system is quickly approaching and its warm moisture source is apparent. Fog enshrouded the summit this am and the snow feels as though it’s soaking up the moisture, becoming a bit more dense with windward areas riming ever so slightly.

Weather and forecast thoughts:

Today’s warmish system peaks later today with heaviest precip. along the crest and in the higher terrain. Any snow showers this morning will turn to rain in Tahoe communities as snow levels scramble back up to 7500-8000′. I suspect that with the warmth of this storm, another layer of warm fog or drizzle may affect the crest, yet again forming a rain crust higher than the forecast snow lines.

Highs today at lake level will be near 40, with temps. wobbling in the low to mid 30’s above 8000′. Tonight the system begins to ease and move out as snow levels drop once again, just in time for any residual showers to finish off the event with a cold dusting. Snow totals will likely end in the 1-6″ range.

Tomorrow the sun returns with seasonal highs near 40 at lake level, low to mid 30’s in the mountains.

Friday and Saturday begin the January thaw that envelops the region through the end of the month. Some showers could sneak in on Fri. and Sat. as Tahoe gets caught between a nascent ridge of high pressure to the east, and the moist southerly flow directed at the PacNW. Snow levels will be very high: up to 9000′.

The ridge amplifies even further Sun. through the middle of next week with highs around the lake in the low 50’s under generally fair skies.

Models and ensembles show an E. Pacific troughing pattern setting up around Feb. 1 with storms again entering the picture. The Pacific jet also looks to extend across the ocean towards the west coast. There’s little agreement today on specifics this far out, and just about any flavor of unsettled weather could befall the area. What does seem likely is an abrupt end to the warm and dry weather of the coming days.

0430 temp. at 6350′ in Carnelian Bay: 29.1 deg. No new precip.

0515 temp. at 8400’ Incline Peak TH: 23 deg. 3-4″? new snow in last 24 hrs.

Backcountry obs.

The warm, damp atmosphere of the past few days finally cooled down overnight. Skies cleared by dawn with the exception of some low clouds and fog hanging over valleys and depressions in the mountains.

Yesterday’s weather tempered my hopes for any cold snow this morning, but alas, a few inches of cold, light snow sat atop the recently fallen dense Sierra cement! Skinning up the peak, snow felt largely right side up (denser below, lighter atop). Little to no wind effect marred the snow surface except for the slightest wind ripple on above treeline terrain within 100′ of the summit.

The cold, light surface snow skied remarkably well: fast, soft, and playful, it flew like pixie dust. Tracks from skiers over the past two days were largely filled in, creating a blank canvass primed for the signing. Despite under-performing in snow totals, the dense snow from this most recent cycle (1/20-1/22) has further fattened up coverage, rounding out the remaining boulders and stumps whose teeth have nipped, bitten, and ground ski bases all season. When skiing steeper terrain, the cold new snow on top ran down the length of gullies as small, manageable, cold sluffs, failing to trigger any larger instabilities. Cold, fresh, snow atop a soft, dense base: a sneaker powder day!

Weather and forecast thoughts:

Today’s surprise has likely heated and thickened as of this writing. Temps today should break the freezing mark in most backcountry zones and reach the low 40’s around the lake. Plentiful sunshine will dominate giving a nice reprieve from days of misty showers and gloom.

Tonight temps will cool back off just in time for another small system to affect the area starting early Weds. am through Weds. night. Snow will again be largely confined to the higher elevations above 7000′. If precip. begins early enough tomorrow morning, snow levels could start out below lake level, but then rise throughout the day before ending entirely Weds. evening. This one won’t be a big producer, dropping a few inches at max.

The end of the week into the weekend is no longer looking as tranquil as previously thought. A ridge of high pressure will build over the inner mountain west, but because Tahoe sits between the high and the active flow into the Pacific NW, some moisture could sneak into the area Fri. and Sat. as it skirts around the influence of the high. Some models are more bullish than others. Anything that does fall will be light and liquid, even up to around 9000′. Temps. will be warm with highs in the mid 40’s around the lake and lows in the low 30’s, possibly warmer.

By the end of the weekend and into early next week, models continue to show warm and dry weather with highs starting to tickle 50 around the lake. The dry weather does look short lived as an extension of the Pacific jet appears to rebuild and take aim on our area around Feb. 1 & 2. The flavor and track of any storms is yet to be determined.

0430 temp. at 6350′ in Carnelian Bay: 34.7 deg. / trace new snow and .16″ rain

0530 temp. at 8650′ Tamarack TH: 28 deg. / 6-8″ new storm snow

Backcountry obs.

This cycle appears to have under-performed for snowfall totals, but played as predicted for snow levels and warmth. This morning a snainy mix fell along the lake as I drove en route to Tamarack. Around 6600′ the snain changed over to all snow and quickly began accumulating a few hundred feet higher up.

At the trailhead, winds were light to moderate and snow fell around 1″ an hour. Yesterday’s tracks were nearly covered and I noted around 6-8″ of total storm snow. The snow’s density, especially down low, made setting a new skin track fairly easy as I didn’t sink down more than a few inches. Snowfall increased as I ascended and by the final third of the climb, snowflakes accompanied each breath. It’s been awhile since the last time I inhaled falling snow on a tour: a welcome change.

Snow on the top third of the mountain had a density change within it as noted by the trap door feeling with each stride. Ridges held soft wind pillows, but any wind texture was minimal. No obvious instability (whumphs, cracking, or reactive ski cuts) was noted.

Sticking to ridges and lower angle terrain, the skiing was great: soft underfoot and not too grabby. Much like previous warm storms this year, the snow in the higher elevations is playful and forgiving, making turns on fat features creamy, forgiving, and fun.

Weather and forecast thoughts:

The weekend storm cycle has delivered rounds of high SWE (snow water equivalent), great base-building snow, but it has been confined to areas above 7000′, and at times even higher. Yesterday afternoon rollerballs began coming off features above 8000′ indicating rapidly warming, moist snow. Throughout the storm on Sat. and Sun., periods of clouds and sun with high humidity and warm temps even reached the higher elevations near 8500′. Rain fell for much of the afternoon just above 7000′ on Donner Summit. The snowpack and coverage in higher areas continue to fatten, but the 6500-8000′ range hosts a sloppy combo of every imaginable type of wet snow. When the storm wraps up later today, I’m not sure it will have added any appreciable coverage opening more zones near 7000′.

Today more snow and rain showers will pass through the area before finally giving way to clearing skies tonight. Snow levels will shuffle between 6500-7500′ throughout the rest of the storm. A few to maybe 6″ of additional snow could fall in higher backcountry zones, especially along the crest. Temps will get to the mid-upper 30’s around the lake to near freezing around 8000′.

Sun returns tomorrow with a break in the weather and highs near average (flirting with 40 deg. at lake level), before another weaker system moves in for Wednesday. Much like the pair of storms this weekend, Wednesday’s system will be warm with snow levels just above lake level that will ping pong depending on time of day and precip. intensity. Snow totals above 8000′ should max out at 3-6″ of wet snow with .10-.25″ of rain at lake level.

Once the Wednesday system clears out, warmer and drier conditions look to take hold for next weekend and the remainder of January as a ridge of high pressure builds over the west. Ensembles do hint at ridge transience and the possibility of the storm track firing back up in the first few days of February.

Get out and enjoy what’s there!