Good morning. This is Wendy Wagner with the Chugach National Forest Avalanche Information Center on Sunday, March 4th at 7am. This will serve as 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).
There are pockets of MODERATE danger on east, south and westerly aspects for sun initiated moist point release avalanches. These will be found in areas where the sun breaks through the clouds and warms the surface snow. There are also pockets of MODERATE danger on steep slopes for sluffs and small wind slabs in scattered areas that saw slight winds yesterday. In areas without sun effect and on slopes less than 38 degrees there is a generally LOW danger. Summit region forecast
The light, low density powder trickling in over the past couple days has added around 10-14 inches of fluff now in many locations. This has come in with little to no wind and is being savored by many at all elevations. Avalanche activity has been in the form of loose snow avalanches on steep slopes within this light snow as well as very small shallow soft slabs being reported from the east side of Turnagain Pass.
This blanket of fluff over the mountains will be very susceptible to any slight change in the weather conditions – including SUN. Today winds should remain calm, temperatures below freezing, but the sun could come out fairly strong in some areas – changing the game on any east through south through west slopes.
Moist point release avalanches will be likely in areas where the sun is heating up the surface. These can release naturally, often below trees and rocks, but also by a person or snowmachine. Any signs of roller balls and sticky snow will be a clue that snow is warming and becoming unstable. If the sun does come out in full force, watch for these to become quite big in certain areas with sustained steep slopes and gullies facing the sun such as the east side of Seattle Ridge.
Dry snow sluffing should continue on steep slopes without sun effect today. The cold temperatures overnight will add to the looseness of the surface and keep sluffing prevalent where slopes are steep enough (around 40 degrees and steeper). Sluff management skills, such as being aware of the size and location of your sluff, will be necessary as these can become dangerous if you get knocked somewhere you don’t want to go such as a cliff or under your own pile of debris.
Wind slabs: Though the winds are not expected to increase today it is good to keep in mind that it will not take much to blow the loose surface snow into small to medium size touchy wind slabs. This is most likely to occur at the upper elevation peaks and ridgelines.
Light snow showers and mostly cloudy skies covered our region yesterday with around an inch or two of very light fluff accumulating. Winds continued to be light (less than 10mph, with a few hours in the teens at the Seattle Ridge station) from a northerly direction above treeline and calm below treeline. During the heat of the day, temperatures hovered just below 20F above treeline and near 30 degrees below treeline.
Overnight, temperatures have dropped and are sitting in the upper teens at sea level and decreasing to 7 or 8F on the ridge tops. Winds remain light from the north on the ridges where they are forecast to remain today. Skies look to be partly cloudy this morning and should continue to clear through the day with temperatures rising to the mid 20’s around treeline. It could be fairly balmy out there today if the sun really breaks though.
CNFAIC Weather Page and the NWS forecast
I will issue the next advisory Monday morning. If you get out in the backcountry we want to know what you are seeing. Please send us your observations using the button at the top of this page or give us a call at 754-2369. Thanks and have a great day.