Two natural avalanches on Polaris Point.

Oddly enough both my partner and I had issues with our phones today and were unable to take photos of anything we saw. Apologies...

We toured the Polaris Point area today (Feb 27) with a plan to avoid avalanche terrain but provide ourselves with the opportunity to see if natural avalanches occurred in the area recently. We saw two natural avalanches that occurred on Feb 26. We assess the crown on one at Polaris Point proper. From the valley floor, we saw a second similar avalanche in more wind protected, open below treeline terrain to the east at the same elevation/aspect.

Performing a crown profile on the avalanche at Polaris Point we determined that the avalanche occurred sometime on Feb 26 as the bed surface was covered under 1 foot of storm snow at the more wind protected east end of the crown. The avalanche may have been triggered by cornice fall at the west end of the crown. Slope angle ranged from 32 to 48 degrees. Crown depth was 2 feet and the avalanche was a size D2. We saw significant debris in the trees below, but saw no broken trees. The avalanche failed at the old/new snow interface on 5 to 7 mm surface hoar that is now collapsed and unreactive in the crown. Snowpit tests in the crown scored ECTX and CTH-29 Brk on this surface hoar layer. HS at the crown was >400cm.

Other observations of note today were widespread tree bombs below 7,400' that decreased drastically above 7,500'. We noted some roller balls from snow falling off of trees at the lower elevations. Along the wind loaded and corniced ridge between Polaris Point and Stanford Rock we intentionally collapsed several cornices. We created some short cracks in the wind slabs around these cornices but no avalanches. One larger cornice drop entrained new snow but did not cause slab failure.

Driving along Hwy 89 from Tahoe City to Truckee around 1:45 pm we experienced a rain/snow mix at 6,200'. We saw a few size D1 loose wet avalanches in the low elevation terrain along the Truckee River corridor.