Tahoe Backcountry Snow

0430 temp. at 6350′ in Carnelian Bay: 15.2 deg. & 94% RH

~ 2″ new snow

0515 temp. at 8650′ Tamarack TH: 4 deg.

6-8″ new 48 hr. snow

Backcountry obs.:

Despite last week’s warmup even at the highest elevations, the recent trough of low pressure and successive waves have left the Tamarack backcountry covered in 6-8″ of cold, blower powder resting atop a firm suncrust. The past two days have been cold and unsettled with heavy convective showers popping up each afternoon, adding fresh snow to the mountains. Yesterday afternoon a few cells dropped 1-2″ of cold snow in 15 minutes around North Lake Tahoe.

The result this morning was brilliant, cold pow under mainly clear skies and light winds that skied beautifully. Some wind effect and settling had thickened the new snow such that turning into the crusty bed layer beneath was a nearly nonexistent concern on the highest reaches of above treeline bowls and chutes. Only at the bottom of each run was the crust from last week’s warmth evident. What a way to bid farewell to the many excellent powder filled dawn patrols of 2024!

Expect crusts to begin forming today as the new snow warms, especially on solar aspects, and begins transitioning to spring snow by the middle of the week. Corn takes time, so it may be until the middle to end of the week before many areas host a plentiful corn bounty if conditions (warm sunny days, refreezing, clear nights) align and hold.

Weather and forecast thoughts:

Last night was likely the coldest night of the spring and possibly the last very cold night of the season. Starting today, temps. begin moderating under sunny skies with highs reaching the upper 30s around the lake, 20s in the backcountry. Tonight will once again be cold – but not as bone chilling as last night – leading into a few more degrees of warming and sunshine for tomorrow. A weak disturbance wanders into the northern Sierra tomorrow afternoon, which could kick off a stray snow shower or two along the Crest, but mainly north of Tahoe.

Spring returns on Mon. as sunny skies and warmer temps take hold. Highs by the middle of the week will reach well into the 50s, even flirting with 60 by the end of the week, under mainly clear skies. Nights will cool off, but towards the end of the week don’t appear to offer solid refreezes – maybe just modest surface refreezes in open areas. If things don’t get too warm, this could be a prime spring skiing window, especially around the middle to end of the week as recent snows need time to melt and freeze to form corn.

Models for next weekend are mixed with quite a few showing a trough of low pressure coming into the PacNW, and possibly dropping a weak cold front into the Sierra. This may cool off high temps 5-10 degrees, increase SW winds, and maybe bring in a few more clouds.

Spring looks to continue further out with no major storms or significant cool downs on the horizon. The focus now shifts to monitoring the daily melt/freeze conditions to see if Tahoe gets a good corn season.

The tide has turned and the snowpack will quickly begin dwindling at middle elevations and even higher as the days warm and lengthen. Spring can bring late season storms in April and May, but with the accelerating melt ahead, this morning was likely last call for Tahoe backcountry powder in 2024.

0600 temp. at 6350’ in Carnelian Bay: 27.0 deg. & 95%RH

New snowfall: 9”

Backcountry obs.:

New snow and little wind overnight will create superb conditions today.

Weather and forecast thoughts:

Bands of snow showers will continue adding to the already respectable new snow amounts from yesterday’s storm. Expect up to another foot in the mountains today through Sun. morning.

Early next week skies clear and temps warm into the 50s as a transient ridge swings through the area.

Later in the week another trough of low pressure looks to arrive to Tahoe brining rounds of snow showers late in the week and into next weekend, potentially brining more spring powder to the backcountry.

Get it!

0430 temp. at 6350′: 30.2 deg. & 85% RH

New snowfall: 3″

0515 temp. at 8650′ Tamarack TH: 16 deg.

New snowfall: 6-10″

Backcountry obs.:

This morning a measly 3″ of thick, new snow coated the ground just above lake level. As expected, totals increased dramatically with elevation and 6-10″ of cold, new, right side up snow had completely reset the backcountry in the Mt. Rose area.

Gusty winds from the SW – NW accompanied last night’s storm creating various textures and patterns (all soft) across the snow surface and a wide distribution of observable new snow totals. Some areas appeared to have no more than 6″ while others approached a foot. All previous tracks and crusts have been completely covered and are imperceptible underfoot.

While no obvious instabilities occurred while breaking trail to the summit, active windloading occurred on N-E-S aspects throughout the early morning. I anticipated unstable wind slabs on lee facing chutes and bowls, but did not trigger any instabilities despite my intentional efforts. The new snow appeared to have bonded well with underlying soft snow and crusts, and becomes generally lighter towards the top.

All this to say that the skiing is, once again, excellent. Another storm has wandered in and reset the snowpack, allowing skiers to lay down fresh tracks on a deep base. The new snow isn’t blower, but invites opening up elongated, fast powder turns with a springy base and not a hint of crust or hardness underfoot. Today’s a day to open it up and rip the most elegant line possible.

Weather and forecast thoughts:

March 2024 stands out as the gold star month of the winter. It started out with a massive dump of over 60″ at lake level and is now set to finish with a week-long parade of cold, medium-sized storms dropping just enough powder to reset the snow surface with cold, fun snow that has been largely stable.

Looking at the forecast, today will be partly cloudy and cold with highs around the lake in the middle 30s, 20s for the backcountry above 8000′. The strong sun angle and breaks in the clouds will heat up the new snow just enough to form crusts and density changes in sun-exposed areas, but persistent cloud cover will hopefully keep this less widespread than if today were completely bluebird. Tonight will be cold and partly cloudy.

Tomorrow another system arrives just in time for the weekend. Models this morning are trending wetter as the much-watched cut-off low taps into subtropical moisture as it drops south along the West Coast. This won’t be a big storm by Sierra standards, but has the potential to put down more snow than last night’s system over a longer period of time.

Snow showers will pick up in number and intensity tomorrow afternoon and into tomorrow night, continuing through Sat. and Sun. before tapering off Sun. evening. Zones above 8000′ and along the crest will receive the highest snow totals, however, decent amounts (3-8″) can be expected around town by storm’s end. In the backcountry up to 6″ falling every 12 hours or so from Fri. PM through Sun. AM looks probable. Temps will be in the 20s at night and 30s during the day with lower values in the mountains. The high sun angle will add instability to the atmosphere each afternoon, promoting convective showers that could put down brief periods of heavy snow (1-3″ per hour). A clap of thunder Sat. and Sun. afternoon isn’t out of the question with these showers.

By the time the system wraps up late Sun., another 12-16″ in the backcountry isn’t out of the question, maybe more if the storm wobbles a bit closer to our area and/or the subtropical jet kicks in a bit more than expected.

Next week starts out with a ridge of high pressure moving into the area promoting warmer temps and sunshine. Spring will return as highs climb into the 50s with lows dipping to freezing and below each night.

Later in the week, more cold, unsettled weather is showing up in medium range forecasts. A return to the cool, showery pattern looks possible, hopefully delivering more spring powder refreshes. Keep it comin’!