Front Range
AvalanchePaul Rogers · Jan 14, 2018 · Front Range
Weather
Clear skies. No precipitation. Temps below TL around 30 degrees, above TL 20-25, with windchill estimated at 10-15. Winds near TL 25-30 with gusts up to 40 in the later afternoon. Ridge top winds looked to be much stronger. Moderate transport & loading near TL, with intense transport at ridge top - typical Front Range blowing snow up into the atmosphere. Surface forms near TL was a 2-3cm wind board of DF's.
Snowpack
- Below TL, HS of 70-80 cm. 50cm of new snow from last week's storms, resting on a crust/facet layer, and below that, mostly faceted. Below TL snowpack is generally weak with no slab. Foot pen to ground. - Near TL, HS of 100cm, increasing to 135-150 in wind deposition areas. Observed the 50 cm of recent storm snow to be stiffening. Three significant weak layers to note. Crust/facet layer 50 cm down with the past week's storm snows resting on top with hardness of 4F and F+. Thin, small (2mm) facet layer down 70cm with 1F slab over & under it. And the ever present basel facets and depth hoar resting at the bottom of the snowpack with a decomposing crust on top of it. Depth hoar 3-4mm. - High Alpine - did not venture up to ridge tops due to high winds and blowing snow. - Snowpack Tests at 12,000 on ENE aspect/wind loaded, HS135: CTM (SC) on FC 50 down. ECTN 50 down and 70 down. Would be interesting to perform PST on above mentioned weak layers - even though ECT tests did not cross the block on these layers, the general snowpack stratigraphy does not inspire confidence.
Avalanche
-Observed one recent D2, and another slightly older D1 that was beginning to be filled in, on steep 40 degree, high alpine E slopes under cornice on headwall east of point 12,424 in pump house drainage. Storm slabs, appeared to be naturals, ran to bottom. -Observed pinwheels and rollerballs in afternoon on steep, rocky, E and SE aspects.