Weekly Recap Friday 1/10/20 - Thursday 1/16/20 This week on As the World Terns: By FAC Intern Rob Millspaugh. Video By Zach Guy is here.
The last week featured nearly continuous low-density snow and light southwest winds with roughly 2-3 inches of SWE. The anomaly was near Marias Pass where artic air leaked over the divide and caused gusty winds from the East. The influx of cold air brought us the coldest temperatures of the season with lows in the single digits throughout the advisory area and well below zero at Snowslip and Flattop. Avalanche activity complemented the active weather pattern. Even light winds were enough to reformat unconsolidated powder snow into windslab. Loose-dry avalanche and windslab became regulars in our problems list pub. Observers reported over 70 D1 avalanches during the week. However, more concerning were the handful of D3-4 slides spotted during Wednesday’s clear conditions. These large avalanches failed on or stepped down to Persistent Weak Layers. They are the large brute in the corner waiting to brawl. Temperatures Thursday trended back towards freezing and storm slab instabilities replaced loose-dry. The recent accumulation of snow at low elevations means they’re now in play. For us and for avalanche.
