Tuesday, December 2nd 2014 6:55 am by John Fitzgerald
ARCHIVED ADVISORY - All advisories expire after 24 hours from the posting date/time.
The avalanche danger is MODERATE today in the alpine, where newly formed wind slabs up to 10” in depth will be easy to trigger on steep leeward slopes. At treeline the danger is LOW, with the exception of isolated wind loaded pockets in steep terrain. Below treeline the snowpack is still too shallow to warrant a danger rating.
Early season hazards such as shallowly buried rocks, stumps and small glide cracks require careful travel, especially below treeline.
The next advisory will be Thursday Dec 4th at 7am.
Avalanche Outlook for Wednesday: Expect wind slabs to continue to build at a modest rate through Wednesday. A pattern of unsettled weather will bring some additional light snowfall and enough wind to keep the danger at MODERATE in the alpine for Wednesday.
|Show the Complete North American Avalanche Danger Scale|
|Travel Advice: Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.|
|Travel Advice: Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.|
Our first, in a series of four, Fireside Chats begins Thursday December 4th! These will be held in both Girdwood and Anchorage. Thursday night's Chat will be at 6:30pm at the Glacier Ranger Station in Girdwood. The topic will be - Intro to Avalanches: Terrain and route finding, presented by CNFAIC forecaster John Fitzgerald. Mark your calendar!
A modest amount of new snow combined with older low density snow and steady winds out of the East/Southeast have formed wind slabs on leeward aspects. These slabs will be sensitive to human triggers and will be up to 10” in depth. Expect them to be easiest to trigger as they are forming. Keep in mind that while the predominant winds have been out of the East, wind changes direction as it interacts with terrain. Your best bet is to be on the lookout for shooting cracks in the snow, upside down snow, or surfaces that are smooth and pillowy. These are signs of recently formed wind slab. Avoiding these wind loaded areas, especially in terrain over 35 degrees will be the best way to manage this avalanche problem today.
A large Low pressure system centered in the Bering Sea that has made its way eastward along the Aleutians has brought with it precip and winds to the mountains around Eastern Turnagain Arm. Snowfall amounts have been greater to the West and less on Turnagain Pass. Weather station data from the Girdwood Valley is currently unavailable.
A warm front associated with this Low has brought slightly warmer air over the area this morning. Fortunately temps have remained cool enough to keep the precip in the form of snow. As this frontal boundary passes expect temperatures to cool and light snow to continue into the daytime hours.
Today we can expect another 3-5 inches of snow. Temperatures at 1,000’ will be in the low 30s F. Ridge top winds will be in the 10-20 mph range.
PRECIPITATION 24-hour data (6am - 6am)
|Temp Avg (F)||Snow (in)||Water (in)||Snow Depth (in)|
|Center Ridge (1880')||25||2||.2||20|
|Summit Lake (1400')||24||3||.3||5|
|Alyeska Mid (1700')||n/a||n/a||n/a||n/a|
RIDGETOP 24-hour data (6am - 6am)
|Temp Avg (F)||Wind Dir||Wind Avg (mph)||Wind Gust (mph)|
This is a general backcountry avalanche advisory issued for Turnagain Arm with Turnagain Pass as the core advisory area (this advisory does not apply to highways, railroads, or operating ski areas).
Riding status is not associated with avalanche danger. An area will be open to motorized use in accordance to the Forest Management Plan when snow coverage is adequate to protect underlying vegetation. Backcountry hazards including avalanche hazard are always present regardless of the open status of motorized use areas.
(Updated: Jan 13, 2019 )
|AREA||STATUS||WEATHER AND RIDING CONDITIONS|
|Twentymile:||Closed||Closed. Forest Service is monitoring conditions.|
|Lost Lake Trail:||Open||Please stay on trail to avoid resource damage through forested areas.|
|Primrose Trail:||Open||Please stay on trail to avoid resource damage through forested areas.|
|Resurrection Pass Trail:||Closed||Closed for the 2018/19 season. Next season will be open to motorized use.|
|South Fork Snow River Corridor:||Open|
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