Good Morning backcountry travelers, this is Carl Skustad with the Chugach National Forest Avalanche Information Center on Friday, January 9, 2009 at 7am. This will serve as a general backcountry avalanche advisory issued 5 days a week Wednesday-Sunday for the Turnagain Arm (Turnagain Pass is the core advisory area). Local variations always occur.
There have been reports of skiers and snowmachiners getting deep frost bite on their toes and faces over the past couple days. Please be careful with these super cold temps.
We would like to give a huge THANK YOU to the latest batch of CNFAIC Observers, Blaine and Nancy from the Alaska Avalanche School, and the Friends of the CNFAIC for a great weekend of avalanche observer training. Braving the freezing cold temps really shows your commitment to the local mountain community. We look forward to your future observations. Thanks again.
MOUNTAIN WEATHER ROUND UP
In the last 24 hours…
-The Center Ridge weather station at 1800 feet in Turnagain Pass-
-The Grandview weather station at 1100 feet along the railroad tracks-
Recorded 0 inches of new snow. Current temp is -5 degrees F (3 degrees warmer than yesterday)
-Sunburst weather station at 3800 feet in Turnagain Pass-
Recorded light winds averaging 6 mph from the NE over night. Yesterday this station saw winds in the high teens and a gust to 24 out of the NE. Current temperature is 6 degrees F (1 degrees warmer then yesterday)
-Surface Analysis Maps-
A 980 mb low is setting in the gulf. We saw the front of this system yesterday as cloud cover bumped over the range from Prince William Sound. Don’t expect a lot out of this low as it is getting pulled easterly toward the panhandle.
The forecast continues to show a change in the jet’s pattern on Saturday night or Sunday when it is predicted to shift and flow south to north from Hawaii toward us.
As of 5:30 am this morning…Shows that it is pretty calm above us. Most of the moisture is heading to AK’s SE panhandle.
The Middleton radar actually shows a small wall of light-moderate precip south of Cordova. The Kenai radar shows does not show very much.
-General Weather Observations- We actually have an above zero temperature this morning in Girdwood, plus 1 deg F. A mid elevation inversion indicates the atmospheric mixing is starting to occur. Temps on the ridgetops are 9-10 degrees warmer than valley bottoms with the exception of Portage were -10 is being recorded.
PRIMARY AVALANCHE CONCERNS
-Faceted surface snow
-Ridge top wind slabs
SECONDARY AVALANCHE CONCERNS
-Glide Cracks (see photos)
WATCH OUT SITUATIONS
-The next storm or wind event
AVALANCHE AND SNOWPACK DISCUSSION
No change from yesterday. Normal travel cation is advised. Yesterday we put 4000 feet under our belt as we climbed up Penguin Ridge to get a feel for the Girdwood Valley snowpack. No surprise that we found very large surface hoar at mid elevations. This surface hoar is some of the best I’ve seen. It’s three dimensional, and tough. This stuffs got teeth and it’s going to give us one heck of a week layer. The best thing that could happen would be warm temps and rain to get some warmth into our snowpack. This is a possibility with the jet stream shifting next week. Let’s keep an eye on the NOAA weather forecasts and be ready when the next storm hits us, because the avalanche hazard will increase whenever that happens.
We have a grab bag of weak layers near the surface that WILL become a problem when the next big storm comes in….
-This cold weather has created a bad temperature gradient in the top 1-2 feet (~40cm) of snow. Recent snow temperatures taken on Sunburst, Main Bowl, Magnum, and Lips show conditions favorable for the formation of facets. Plus, we have confirmed these facets through our magnifying glasses in the surface snow. Basically, this means that a bad weak layer is forming in the current surface snow. This weak layer is everywhere. That means all aspects and elevations.
-The recent clear weather, calm winds and cold temps have created surface hoar from the highway to the ridgetops in certain areas. The biggest surface hoar is found at low to mid elevations up to about 2800 feet. This is the prime elevation of the Tincan trees; so, keep that in mind during the next storm. Don’t get complacent with areas like this that you assume are always safe.
The facets that formed on the ground in October continue to show signs of improved stability. This layer, however, is still a concern for future avalanches, especially during and after the next big storm.
WESTERN PRINCE WILLIAM SOUND-
500 AM AKST FRI JAN 9 2009
.TODAY…VARIABLE CLOUDS IN THE MORNING THEN MOSTLY SUNNY IN THE
AFTERNOON. HIGHS 5 TO 20 ABOVE. NORTHWEST WIND 10 MPH
EXCEPT NORTH 25 TO 35 MPH NEAR SEWARD. WEST WIND 25 TO 35 MPH IN
.TONIGHT…MOSTLY CLEAR. LOWS ZERO TO 10 BELOW EXCEPT 5 TO
15 BELOW INLAND. NORTHWEST WIND 15 MPH EXCEPT NORTH 20 TO 25 MPH
.SATURDAY…MOSTLY SUNNY IN THE MORNING THEN BECOMING MOSTLY
CLOUDY IN THE LATE AFTERNOON. HIGHS IN THE MID TEENS TO LOWER 20S.
VARIABLE WIND TO 10 MPH.
.SATURDAY NIGHT AND SUNDAY…CLOUDY WITH A CHANCE OF SNOW.
LOWS IN THE TEENS. HIGHS IN THE UPPER TEENS TO MID 20S. EAST WIND
10 TO 15 MPH.
.SUNDAY NIGHT…CLOUDY WITH SNOW LIKELY. LOWS 5 TO 15 ABOVE.
TEMPERATURE / PRECIPITATION
SEWARD 10 5 18 / 0 0 0
GIRDWOOD 3 -5 12 / 0 0 0
Thanks for checking the CNFAIC avalanche advisory. Have a great day.