Tahoe Backcountry Snow

0600 temp. At 6350’ in Carnelian Bay: 37.6 deg.

0.01” rain overnight

No backcountry obs.

Weather and forecast thoughts:

I planned to tour this morning, but the mostly clear radar steered me elsewhere. If anything fell last night, it probably totaled and inch or two. Remote sensors show gusty winds and temps. in the 20’s in the backcountry. Based off the antecedent surface conditions, crusts and hard surfaces seem all but certain until the current system drops some snow.

Today dawned around the lake with broken skies and gusty winds with temps. in the mid 30’s. Models continue to show the storm coming in throughout the day and lasting through tomorrow before the second round gets going Sun. night and Mon. Not much has changed in terms of higher snow levels (6500-7500′), QPF, and track. The timing of both systems has been pushed back, so hopefully that accounts for the lackluster performance overnight, rather than a disintegrating storm. Most organized precip. remains NW of the area, so for now it’s a waiting game.

Longer range forecasts still show another mild system coming in mid-late next week followed by a warming and drying trend late week through the end of the month.

0600 temp. at 6350′ in Carnelian Bay: 35.2 deg.

No new precip.

No firsthand backcountry obs. this morning.

Backcountry obs.:

Based off conditions yesterday and remote sensor readings atop Slide Mountain, I did not head out into the backcountry this morning. High temps. reached 44 deg. yesterday at 9600′ with light to moderate S winds. Lows last night stayed a few degrees above freezing. Conditions are likely cooked and in need of new snow, even at the highest elevations.

Weather and forecast thoughts:

New snow is needed and luckily, that’s what’s in the forecast for this weekend. This morning dawned dreary and a bit warm, signaling the arrival of a warm series of storms slated for the weekend into early next week.

Models this morning are trending a bit wetter for the first system coming in tonight. NWS Reno issued a Winter Weather Advisory last night for areas above 6500′ for 3-8″ up to 7000′,and 8-12″ above 7000′. Because this system will have less potential for spillover, zones along the crest will be favored for higher snow/rain totals. Winds will increase from the SW as the storm approaches, but don’t look to be as strong and intense as those from the last cycle.

Sun. night, the next wave comes in, which will favor areas from Tahoe south into the Eastern Sierra. This system will again be warm with snow levels mainly at 7000′ and higher. There is more convective energy and forcing available with round two, so NWS issued a winter storm warning for the period of Sun. PM to the wee hours of Tues. AM. Snowfall totals for the higher elevations will be between 1-2′ of new Sierra cement. The stronger dynamic of this storm will allow areas east of the crest to get in on more rain/snow action.

The weekend looks promising for a 1-2’+ refresh and base building above 7000′, but around the lake expect another sloppy mix of rain and snow.

Looking beyond the weekend storms, another warm, yet weak disturbance shows up in the models for midweek, followed by a solid signal for a ridge of high pressure building next weekend and holding on for the remainder of January. A ridge would likely warm things up and keep us dry, deflecting the storm track north of us. Could it cook up some late January corn snow?

As we enter February, some models suggest the ridge moving out and a wetter pattern returning. It’s a long way off, but I’m hopeful that winter will return for at least a few weeks. For now, bring on the cement!

0430 temp. at 6350′ in Carnelian Bay: 27.7 deg.

No new precip.

0520 temp. at 8650′ Tamarack TH: 28 deg.

No new snow.

Backcountry obs.

This morning felt like the air mass is beginning to change. Temps. at the Slide Mountain sensor near 9600′ flirted with freezing all night. On the drive up 431, temps. fluctuated between the mid-upper 20’s and low 30’s. At daybreak, skies were overcast.

Most notable this morning was the complete absence of wind. It took me a moment to figure out why the sounds of grooming equipment and traffic could be heard well into the mountains, then it hit me: no wind ripping through the trees. It’s been a while. Also of note was the warmth starting around mid-way up the skin track. Temps. had to be near or above freezing as I needed to shed a layer to not completely sweat through my clothes.

The snow reflected the additional warmth in the approaching air mass. Crusts are now abundant covering more snow than cold soft wind effect. What cold snow remains is becoming ever more dense. Solar aspects hold the thickest crust that’s nearly supportable, while W-NW-NNE aspects in open areas and above treeline host rime-covered pillows and stiff wind board. Do the cardinal math and you can figure out where pockets of soft snow still might be hiding.

Skiing through avy terrain, I observed no red flags or signs of obvious instability.

On balance, the skiing is still fun but becoming a bit more athletic. Good training.

Weather and forecast thoughts:

Today and the first part of tomorrow will be warm and dry due to a ridge of high pressure building over the area. High temps will warm well into the 40’s around Tahoe and with abundant cloud cover, expect the snow to cook as radiation gets reflected back to Earth from the cloud cover.

The weekend forecast for warm storms Fri. PM-Mon. continues to hold. Details regarding timing are emerging, but the theme of snow levels moving between 6500-7500′ throughout the period holds. By Mon. PM, 1-2′ of dense Sierra cement can be expected above 8000′. Lesser amounts east and between 7000-8000′ are a good bet. Little to no accumulation is expected at lake level.

There will be two main pulses of energy: Fri. night – Sat. and Sun. pm into Mon. Both systems will tap into subtropical moisture, but the first looks to be weaker, in addition to having a splitting nature as it arrives. Expect less spillover moisture from the crest with the first wave.

The second wave Sun. pm-Mon. will have a stronger cold front and low pressure component creating more efficient forcing as the system hits the Sierra. This one will likely produce the most rain/snow. Snow levels will be high once again with this one, unlikely to produce much, if any, accumulation at lake level, but will deliver a healthy load of cement atop the snowpack. Hopefully another heavy, dense snowfall between 7000-8000′ will build coverage and access to lower elevation backcountry zones.

Expect typical strong SW winds to accompany each storm.

Moving towards the middle of next week, another system takes aim on the region, but it looks to be warm, yet again. Thereafter, models are showing a ridge of high pressure developing over the west for the end of the week and next weekend.

There’s lots of warmth this month, but fortunately there is a snowpack and higher elevation zones continue to build up and deliver good mountain fun.