Good morning backcountry travelers, this is Carl Skustad with the Chugach National Forest Avalanche Information Center on Saturday, December 13, 2008 at 7am. This will serve as a general backcountry avalanche advisory issued for the Turnagain Arm Area (Turnagain Pass is the core advisory area). Local variations always occur.
INTERAGENCY AVALANCHE RESCUE TRAINING
On the weekend of December 13-14, there will be an avalanche rescue training taking place this weekend at Turnagain Pass. Please be aware of rescue workers, helicopters, rescue snowmachines and areas set up for rescue training drills. Thanks.
MOUNTAIN WEATHER ROUND UP
In the last 24 hours…
-The Center Ridge weather station at 1800 feet in Turnagain Pass-
Recorded no new snow. Current temperature is 1 degrees F (6 degrees colder than yesterday morning). Total snowpack depth is 60 inches, with a total of 9 inches of settlement since the storms end Wed.
-Sunburst weather station at 3800 feet in Turnagain Pass-
Recorded moderate NW and battling SE winds averaging 10-14 mph. Current temperature is 8 degrees F (1 degrees warmer than yesterday)
-Surface Analysis Maps-
High pressure remains in the area for the weekend.
Fairly clear, possible local fog
-General Weather Observations-
Summit lake is the cold spot again this morning with -8 deg. I sight inversion exist with single digits down low and low teens on the ridge tops.
PRIMARY AVALANCHE CONCERNS
AVALANCHE AND SNOWPACK DISCUSSION
No human or natural avalanche activity reported yesterday. Thursday, a snowmachine triggered avalanche was reported from the Seattle Drainage area. An ABS airbag was deployed and the rider was only partially buried. Still waiting to hear and learn from that rider. He described a crusty bed surface. Lisa went in search of this crust and found it at 2500 feet. It seems to be the upper reaches of that warm spell that occurred last week. The new snow old snow interface continues to be the most current concern, but is bonding better each day. All Lisa’s stability tests had hard results.
Alex continues to find less stable conditions in the Summit Lake Area. This could be expected with a shallower, colder snowpack. He once again had the snowpack collapsing with whoophs around him yesterday. A 2-3 foot snowpack exists by Fresno and Summit. The weak layers there exist on the October snow and the new snow interface. I expect similar conditions near Lost Lake and Central Kenai.
Normal travel caution is advised today. Manage your terrain and follow mountain travel rituals. One at a time, watch your partners, stay clear of terrain traps, and never travel above our partner.
Area’s you could trigger an avalanche continue to remain near rock and cliff bands, wind blown ridges, and areas of shallower snow.
We have started to see glide crack formation on at least four southern aspects in Turnagain Pass. Give these glides plenty of room, they can release at any time pulling snow out right to the ground. (see photo gallery)
WESTERN PRINCE WILLIAM SOUND-
540 AM AKST SAT DEC 13 2008
…STRONG WIND THROUGH TODAY NEAR WHITTIER…
.TODAY…SUNNY. ISOLATED AREAS OF BLOWING SNOW. HIGHS IN THE TEENS.
NORTH AND WEST WIND 10 TO 25 MPH EXCEPT NORTH 25 TO 35 MPH NEAR
SEWARD AND WEST 30 TO 45 MPH NEAR WHITTIER.
.TONIGHT…MOSTLY CLEAR. LOWS 5 TO 15 ABOVE. NORTH AND WEST WIND 10
TO 20 MPH WITH GUSTS TO 35 MPH NEAR WHITTIER AND SEWARD DIMINISHING
.SUNDAY…SUNNY. HIGHS IN THE 20S. LIGHT WINDS EXCEPT NORTH TO
15 MPH NEAR SEWARD.
.SUNDAY NIGHT AND MONDAY…MOSTLY CLEAR. LOWS 5 TO 15 ABOVE.
HIGHS IN THE MID 20S TO LOWER 30S. VARIABLE WIND 10 MPH.
TEMPERATURE / PRECIPITATION
SEWARD 23 14 28 / 0 0 0
GIRDWOOD 14 3 21 / 0 0 0
This concludes todays advisory, the next advisory will be on Sunday the 14th. Thanks and enjoy the cold sun.