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.