Tahoe Backcountry Snow

Backcountry obs.:

Rather than fight the weather, I’ve put away the ski gear for the time being and gotten my backcountry jollies on foot, sampling the newly available trail running opportunities through the ever expanding snow-free zones. As of 3/23, continuous, tacky, open trail exists almost uninterrupted below 7500′ on all aspects, and below 8000′ on all but protected NW-N-E aspects along the NE corner of the Tahoe Basin from the Mt. Rose backcountry to Tunnel Creek.

Snowpack starts abruptly around 8000′ on most treed aspects, but is absent on windward and solar faces all the way up to ridgelines and summits. Where snowpack does still exist, surface snow is more reminiscent of late spring/early summer, pocked and littered with forest debris and rotten from multiple nights of poor to nonexistent refreezes. In the trees, pronounced, rolling undulations are growing ever more-prominent as tree wells melt down to the ground, leaving the remnant fins and waves of deeper snowpack in between. Tree skiing is becoming necessary survival/transit skiing after better turns up high.

Above treeline and 8000′, open N and NE facing terrain is in better shape. Despite lows only bottoming out in the 40s, dry air and radiational cooling have promoted marginal surface refreezes on the majority of nights over the past week, creating supportable snow early each morning. By late morning, temps warming into the 50s under direct or slightly-filtered sunshine has overcooked corn into wet mush on most days. But with the right timing and right objective, fun spring skiing is still out there over higher terrain. The snowpack might be hammered and waning, but it’s still hanging on up high.

It’s spring and the backcountry’s primed for multi-sport days. What’s not to love about biking, running, climbing, and paddling in the same day or skiing a line and mountain biking home?

Weather and forecast thoughts:

Anomalously warm and dry — yet less record shattering — weather will continue through the week and coming weekend (3/25-3/29). Highs above 8000′ on the remaining snowpack will climb into the mid-upper 50s each day with lows in the upper 30s to low 40s in a relatively dry airmass. Expect surface snow in forests to refreeze poorly most nights, especially with any cloud cover, while open areas with a clear line of sight to the sky will cool and resolidify more efficiently each night.

Winter 2026 has been the warmest on record and the past ten days blew away any previous March records by wide margins. Equally notable is that rather than occurring over a day or two, this heatwave has persisted for well over a week–and will continue for another–with multiple waves of extreme warmth. While heat has felt like the norm this season and many folks have already switched their minds to summer activities, it’s worth taking note of the scale of the recent event. It’s truly historic.

On Mon (3/23) NWS Reno put together a graphic summarizing the situation:

The main culprit is the historically strong and resilient ridge of high pressure over the west, directing any and all weather north into Canada. Locations under the ridge bake as high pressure pushes air downward, drying it out and warming it up via subsidence.

This morning (3/24), the ridge remains locked in place, as noted by IR satellite imagery showing clear skies across CA and the jet stream shunting any moisture northward toward into BC and WA.

As a result, while not summer-warm, the next week will continue to be 10-15 degree above average as noted by ground level temperature anomalies for the coming week.

But as has happened both in December and after a bone-dry January earlier this season, eventually the pattern breaks. Models over the past few days have started to agree on a pattern shift pushing the ridge eastward and allowing a trough of low pressure to swing in its place. Cooler and wetter conditions look more likely to return by the beginning to middle of next week.

The exact details of the shift will become clearer in the coming days. For now, expect an end to late spring warmth and the return of cooler temps, and the chance of rain and higher elevation snows starting around the beginning of April.

Backcountry obs.:

The great winter heatwave of 2026 is upon us. Touring inbounds at Diamond Peak at dawn on 3/16, surface snow had barely refrozen near the base area in a protected drainage thanks to overnight inversions. Moving up mountain, snow quickly softened and temps climbed starting around 7000′ and continuing to the summit at 8540′. Light easterly winds and temps in the low 40s greeted me at the summit where snow had barely cooled enough for a weak, surface refirm.

This morning (3/17), low temps and dew points failed to refreeze surface snow, even with evaporational cooling high in the backcountry above 9000′. Temps atop Slide Mountain (9600′) only bottomed out at 46.2°F around 0400. This temperature coupled with 46% RH just wasn’t enough for snow grains to cool and refreeze on their own. It’s March 17 and even at the highest elevations in Tahoe, the snowpack is melting day and night.

As such, expect warm, soft, and slushy snow throughout the backcountry for the foreseeable future. Even after the heat wave’s peak, temps will still be well-above normal, slowing the big melt only marginally. For many backcountry zones between 7000-8500′ where the snowpack was already thin, this event will likely draw a close to the 2026 snow season.

Weather and forecast thoughts:

Sunshine, light winds, and unprecedented warmth will continue through the week and into the early part of this coming weekend, likely peaking on Thurs (3/19). This weekend (3/21-22), the extreme, record-breaking heat fades into much above average warmth (10-15°F above normal) lasting through at least the first half of next week. Beyond next week, some models hint at the return of light precipitation returning, but confidence is low.

This afternoon (3/17) temps reached the low 70s in Martis Valley with mid-upper 60s between 6000′-7000′. In the Tahoe Basin within 100-200ft of lake level, temps remained a bit cooler, only reaching the low 60s due to the cooling influence of Lake Tahoe’s winter-chilled waters. Temps for the remainder of the week will climb even higher reaching the low 70s near and below 7000′ Weds – Fri (3/18-3/20). Temps may remain a few degrees lower near the lake due to the lake’s aforementioned cooling effect.

Lows throughout the week will remain above freezing all the way up to the highest backcountry locations, preventing surface refreezes. Where snowpack remains, it will likely turn isothermal (uniformly 0°C from surface to ground level). Wet snow instabilities and rockfall will become common, especially on sunny aspects and around cliff features each afternoon.

As advertised, the cause of the anomalous warmth is a large, nearly stationary ridge of high pressure that’s creating a summer-like heat dome effect over the American West. As air sinks beneath the high, it dries out and heats up via subsidence, baking away the Sierra snowpack in the process.

To get a sense of how warm this airmass actually is throughout the atmosphere, check out the ensemble models for freezing levels in the Tahoe Basin. Even the coolest models keep freezing levels above 12,000′ until Sun morning (3/22).

Is there any escape at the highest elevations? No. Even the highest elevations in the Sierra will not escape the summer-like heat. Freezing level forecasts for the Owens River watershed, which includes the Eastern High Sierra from the Palisades to Mt. Whitney, keep temps above freezing even above 14,000′ through at least Sat (3/21).

While the Southern Sierra’s high elevations helped it to fare better through the 2026 snow drought–some areas above 10k ft. received near to slightly above average snowpacks going into March–this week’s warmth will rapidly accelerate melt and promote widespread wet snow avalanches and rockfall, especially in couloirs and along rock faces. I anticipate many High Sierra lines being cleaned out and/or littered with rockfall after this week.

Peering ahead into the coming week and into the start of April, models suggest above average temps retaining the upper hand across the Sierra through the 27th, but to a less extreme degree, with some signs of precip reentering the picture. Relief is a long way off.

So grab your bike, running shoes, or whatever else brings you joy in the warm months. There’s still plenty of fun to be had in the backcountry without sliding on snow.

Backcountry obs.:

This has been the week of the corn cycle. Warm sunny days and nights just cool and dry enough to refreeze the snowpack have thrust the backcountry season into peak spring skiing.

I poked around the NE corner of the Basin at dawn on Tues and Thurs (3/10 & 3/12) and found the usable snow line quickly retreating up to near 8000′, especially on S and W aspects. The snowline on N and E aspects is around 1000′ lower.

Inversions have been setting up each night pulling lows near freezing at lake level–and a few degrees below in valleys and hollows away from the warming influence of the lake–while upper elevations have only bottomed out in the upper 30s to low 40s.

Despite the warm lows in the mountains, clear skies, light breezes, and very dry air have helped to refreeze snow surfaces via evaporational and radiational cooling. Because of this setup, mid elevation, forested zones haven’t been refreezing well as radiation from the snow and trees gets reflected back onto the snow surface, heating the snow just enough to inhibit the refreeze. However, open areas with a clear line of sight to space have consistently refrozen each night, providing a supportable, frozen surface to climb early in the morning.

Superficial refreezes demand alpine starts for the best skiing. Early morning sun has been baking E aspects as soon as the first rays touch the snow, softening frozen surfaces into smooth, buttery corn by mid morning. Beyond 10am, intense sun angles and high temps have begun overcooking snow surfaces into wet mush. It’s all about timing.

Weather and forecast thoughts:

Warm and dry weather will continue for the foreseeable future with no real prospects for snow through at least the next 10 days. This weekend (3/14-3/15), a weak cold front will bring an uptick to winds and cool daytime highs by a few degrees from their peaks yesterday and today (3/12-3/13). Even with the cool down, temps will still be 10-15 degrees above average for mid March. (Average highs in Tahoe City this weekend are around 45°F). Expect highs in the backcountry above 7000′ in the low 50s both Sat and Sun with occasional high clouds streaming across the area.

Light to moderate winds from the west on Sat (3/14) will shift around to the N and NE on Sun (3/15) bringing a subtle chill to the air, likely delaying the daily surface melt. If any clouds do end up lingering about overnight, they could keep temps a bit higher, thus inhibiting or blunting the strength of the nightly refreeze.

Warm, dry weather continues and intensifies into the coming week (3/16-3/20) with heat reaching all time record highs for mid March. By mid-late week, high temps in the Tahoe Basin could flirt with or surpass 70°F on consecutive days! Despite the clear skies and dry air, lows, even on the snowpack, are unlikely to fall below freezing each night, putting an end to the current corn cycle and dealing a major blow to the remaining snowpack.

Looking at the climatologically normalized pressure anomalies, ensembles are in good agreement that this event will likely crush records for March heat across the region. These maps show just how anomalous the pattern will be compared to average. This coming week will fall within or above the 95th percentile. That’s big high pressure!

And because high pressure causes the air mass to sink and heat as it descends, the strength of the high correlates to the strength of the heat it generates. Temp. anomalies across the SW will be at the top of the charts for the coming week with highs more akin to early summer than the last full week of winter.

Taking a look at climatology at Tahoe City, highs near or just above 70°F would far surpass current records for the middle of March, which are in the low to mid 60s. And surpassing 70°F would set a new all time record high for the entire month, last set on 3/31/15.

There’s no escape from heat of this magnitude. Even the highest, most protected zones of the Tahoe backcountry will get cooked.

Peering way out beyond next week, warm and dry signals continue into third week of March. More warmth after such an extreme heat event on a below average snowpack may spell the end of the 2026 season for most Tahoe locations.

Now, more than ever, it’s time get what’s left and enjoy the remaining days of the current corn cycle and backcountry season.