0600 temp. at 6350′ in Carnelian Bay: 31.5 deg. w/ 98% RH

Backcountry obs:

Touring around the Mt. Rose backcountry on Thanksgiving Day (11/28) and Sat (11/30) revealed a drying snowpack that has largely remained cold, despite well above freezing temperatures the past few afternoons. A very dry airmass with RH (relative humidity) values in the single digits has kept protected areas above 8500′ cold and fluffy due to evaporative cooling. However, that very same dry air is pulling moisture out of the snow, thinning the dense cement that recently covered twigs, rocks, bushes. As a result, I sank deeper on my last tour, scraping some granite and stumps on my way down. It’s increasingly sharky out there!

Additionally, the excitement for early season turns, along with folks tromping around chopping down Christmas trees created tons of tracks of all varieties throughout the backcountry. Fresh, scratch-free turns are now a rare commodity and will become ever scarcer until a storm system finally brings more snow. And that may take some time.

Weather/forecast thoughts:

The Tahoe Sierra has been locked into strong high pressure and powerful daily inversions the past few days. High temps at lake level have struggled to break 40 deg., while along the peaks and ridge tops, highs have reached the mid-upper 40s. Low temps have been more dramatic with teens and 20s in the valleys while peaks remained in the 30s! Fog and low clouds have also developed in depressions overnight, leaving a coating of heavy frost and surface hoar that glistens with each sunrise.

The powerful ridge over the west will continue to block any storm system from arriving in Tahoe for at least the next week. Expect similar weather as we’ve had the past few days for the next week: cold nights, cool days under mainly sunny skies.

Looking out to the second week in December, models begin to show the possibility of some weakening in the current blocking pattern. Some small storms may affect the PacNW and drop into the Great Basin, just to our east, bringing cooler temps and little precip., if any, to Tahoe. It’s a ways out, but if these weak signals of change to the dominant blocking pattern were to play out, this would be a positive step towards moving the jet stream into a position more favorable for Sierra storms.

The snow will return at some point. Time to exercise patience.