Register for an account and never miss a forecast again!
RegisterRegister for an account and never miss a forecast again!
RegisterFeb 21st, 2016–Feb 22nd, 2016
.
The avalanche danger should gradually decrease on Monday. Watch mainly for new or previous wind slab on the lee slopes near ridges or mid-slope where cross loading may have occurred.
West winds and orographic snow showers mainly at higher elevations should taper off on Monday with lower snow levels. The avalanche danger should gradually decrease on Monday.
The winds and snow Sunday and Sunday night may have built new shallow wind slabs on lee slopes mainly near and above treeline. Older wind slab may linger on similar slopes. Watch for new or previous firmer wind transported snow mainly on the lee N to SE slopes near ridges or mid-slope where cross loading may have occurred.
New shallow storm slab is possible if you are in an area where more than several inches of snow rapidly accumulated Sunday to Monday morning.
Weather and Snowpack
Two fair weather periods in January allowed surface hoar and near surface faceting to occur. These persistent weak layers were buried intact on Jan 3rd and 11th, but are no longer considered a persistent slab threat since several warm and wet systems have tested these layers and since they have been unreactive where identified in recent snowpits.
Dry weather with the warmest temperatures of the winter occurred February 7-10th with temperatures climbing into the 50's in most areas east of the crest.
Snow has dominated since then in the northeast zone and began to bury a crust there with about 2-3 feet of snowfall starting February 11th through Friday.
But rain and mild temperatures were seen in the central east and southeast zones last Sunday and Monday forming a newer crust there. Then the active and cooler pattern began to bury the crust in the central and southeast zones starting February 17th with about 6-9 inches of storm in the near and above treeline Wednesday to Friday.
Another front is crossing the area on Sunday followed by a short wave Sunday night that will generally shifting winds and up to a few inches of snow.
Recent Observations
NWAC pro-observer Tom Curtis was at Blewett Pass on Wednesday mostly reported shallow new snow on a thick crust.
The North Cascades Mountain Guides sent a report Friday for the Washington Pass area and report that the February 11th crust is found at about 65-80 cm. Some but not all tests give hard sudden collapses with sudden propagation. Also some stiff pencil hard wind slab giving easy shears, hidden under about 10 cm of new snow, was been seen near some ridges.
The pro-patrol at Mission Ridge Saturday reported pockets of ski triggered 6-14 inch wind slab during avalanche control on northeast to southeast slopes above about 5800 feet. These slab were releasing on the February 17th crust. Later today a skier triggered a 6-10 inch wind slab and was caught and carried but not injured in a northeast facing chute at about 6300 feet.