Good Morning backcountry travelers, this is Carl Skustad with the Chugach National Forest Avalanche Information Center on Saturday, January 10, 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.
MOUNTAIN WEATHER ROUND UP
In the last 24 hours…
-The Center Ridge weather station at 1800 feet in Turnagain Pass-
No data. The guys from NRCS have been trying t get this fixed an have narrowed down he problem. Look for this station to be back on line soon.
-The Grandview weather station at 1100 feet along the railroad tracks-
Recorded 0 inches of new snow. Current temp is -1.5 degrees F (3 degrees warmer than yesterday)
-Sunburst weather station at 3800 feet in Turnagain Pass-
Recorded light to moderate S, SW winds averaging 10 mph. Current temperature is 6 degrees F (same as yesterday).
-Surface Analysis Maps-
A 1003 mb low is setting in the gulf with little luck pushing inland. AnCNFAIC Staff 983 mb low is on track to give us anCNFAIC Staff chance at precip Sunday or Monday. Don’t expect allot of precip action.
The forecast continues to show a change in the jet’s pattern on Sunday when it is predicted to shift and flow south to north from Hawaii toward us. Currently it is hosing the panhandle.
Light Gulf of AK action!
-General Weather Observations- Back below zero in Girdwood, -3 deg F. Winds are light to moderate out of the S, SW and temps are inverted again today. Valley floor temps are -3 to -24 in Portage and ridge tops are showing low teens.
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. On Thursday we hiked up Penguin Ridge. 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.
500 AM AKST SAT JAN 10 2009
.TODAY…INCREASING CLOUDS WITH A SLIGHT CHANCE OF SNOW IN THE
AFTERNOON. HIGHS ZERO TO 25 ABOVE…COOLEST INLAND. LIGHT WINDS
EXCEPT NORTH 15 TO 25 MPH NEAR SEWARD.
.TONIGHT…MOSTLY CLOUDY WITH A CHANCE OF SNOW. LOWS ZERO
TO 20 ABOVE…COOLEST INLAND. LIGHT WINDS EXCEPT NORTH 15 TO
25 MPH NEAR SEWARD.
.SUNDAY…MOSTLY CLOUDY. A CHANCE OF SNOW IN THE AFTERNOON. HIGHS
10 TO 25 ABOVE…COOLEST INLAND. VARIABLE WIND TO 10 MPH. NEAR
SEWARD…NORTH WIND 10 MPH.
.SUNDAY NIGHT…CLOUDY WITH A CHANCE OF SNOW. LOWS 10 TO
25 ABOVE…COOLEST INLAND. VARIABLE WIND 10 MPH EXCEPT NORTH
10 TO 20 MPH NEAR SEWARD.
.MONDAY…MOSTLY CLOUDY WITH A CHANCE OF SNOW. HIGHS IN THE MID
TEENS TO LOWER 30S…COOLEST INLAND. LIGHT WINDS EXCEPT NORTH AND
WEST 15 TO 30 MPH NEAR SEWARD AND WHITTIER.
TEMPERATURE / PRECIPITATION
SEWARD 20 18 22 / 20 40 40
GIRDWOOD 9 2 12 / 20 20 20
Thanks for checking the CNFAIC avalanche advisory. Have a great day.