Good morning backcountry travelers, this is Carl Skustad with the Chugach National Forest Avalanche Information Center on Sunday, January 4, 2009 at 7am. This will serve as a general backcountry avalanche advisory issued for the Turnagain Arm (Turnagain Pass is the core advisory area). Local variations always occur. Note: We issue advisories 5 days a week Wednesday-Sunday.
MOUNTAIN WEATHER ROUND UP
In the last 24 hours…
-The Center Ridge weather station at 1800 feet in Turnagain Pass-
Still no data. Hopefully it will be back up and running early next week thanks to the Natural Resources Conservation Service. Those guys are awesome. They keep most of the SNOTEL weather stations running around Alaska.
-The Grandview weather station at 1100 feet along the railroad tracks-
Recorded 0 inches of water or new snow. Current temp is -10 degrees F (3 deg warmer than yesterday)
-Sunburst weather station at 3800 feet in Turnagain Pass-
Recorded light to moderate NE winds in the single digits to mid teens. Current temperature is -4 degrees F (12 degrees warmer than yesterday) Note that the winds shifted from the NW to the NE in the last 24 hours.
-Surface Analysis Maps-
The low pressure system that was hanging out in the Gulf has finally moved on. AnCNFAIC Staff serious of lows is heading our direction. These lows may have a better chance at displacing the mega high that is parked over central AK. Look for temps to rise mid weak.
-General Weather Observations-
Temps came up slightly over night. We are seeing a slight inversion today so expect warmer conditions at higher elevations. Winds have shifted from the NW to the NE and E overnight as the pressure systems begin to jockey for position.
PRIMARY AVALANCHE CONCERNS
-October Facets on/near the ground in higher alpine locations
SECONDARY AVALANCHE CONCERNS
-Glide Cracks (see photos)
WATCH OUT SITUATIONS
-Big steep rollovers
-Shallow snow connected to deeper snow (photo gallery)
-If you hear any “whumpfing” or feel any collapsing, then get to safe terrain immediately and call it a day.
AVALANCHE AND SNOWPACK DISCUSSION
Take time to again today to watch yourself and your partners for signs of frost bite.
Yesterday myself and a group of CNFAIC observers participated in an observers training. A big thank you to all our observers. You are to be commended on your dedication to avalanche awareness and safety. Our groups found fairly stable avalanche conditions on all lower elevations up to 2500 feet. Cold temperatures made skin glue all but worthless and snow pits felt like a Ben and Jerry’s ice cream cooler. We found a significant temperature gradient in the top half of most profiles and more faceted snow than than I’ve seen in T- Pass for a long time. All our stability test had hard test results (CT27Q2, CT29Q3, CT25Q2) with failures occurring on a crust sandwich approx. 47 to 60 cm deep, (2 ft).
Possible human triggered avalanche activity should be limited to higher elevations near ridge tops that acquired wind slabs over the last couple of day or on complex alpine terrain near steep rollovers and cliff bands. The story is still the same and it will be for some time. Shallow faceted snow exist throughout the Chugach and Kenai Mountains. This is not a typical snowpack for this time of year in this area. The shallow nature of this pack has the potential to initiate an avalanche where the week layers are close to the surface and propagate into deeper slabs.
Our snow surface is full of surface hoar and near surface facets. This surface condition is very important to remember as it will be our next week layer when buried. We have observed this week snow on all aspects and all elevations.
WESTERN PRINCE WILLIAM SOUND-
500 AM AKST SUN JAN 4 2009
…STRONG WIND TONIGHT THROUGH EARLY MONDAY AFTERNOON NEAR SEWARD…
.TODAY…MOSTLY SUNNY. HIGHS 15 BELOW TO 10 ABOVE…COOLEST
INLAND. NORTHWEST WIND 10 TO 15 MPH EXCEPT NORTH 25 TO 35 MPH
NEAR SEWARD. WIND CHILLS 10 BELOW TO 25 BELOW.
.TONIGHT…MOSTLY CLEAR. LOWS 10 BELOW TO 20 BELOW EXCEPT ZERO TO
5 ABOVE NEAR SEWARD AND WHITTIER. NORTHWEST WIND 10 TO 20 MPH
EXCEPT NORTH 30 TO 45 MPH NEAR SEWARD. WIND CHILLS 10 BELOW TO
.MONDAY…MOSTLY SUNNY. HIGHS 10 BELOW TO 5 ABOVE…COOLEST
INLAND. NORTHWEST WIND 10 TO 20 MPH EXCEPT NORTH 30 TO 45 MPH
NEAR SEWARD. WIND CHILLS 10 BELOW TO 25 BELOW.
.MONDAY NIGHT…CLEAR. LOWS 10 BELOW TO 20 BELOW EXCEPT AROUND
ZERO NEAR SEWARD AND WHITTIER. NORTHWEST WIND 10 TO 20 MPH WITH
GUSTS TO 35 MPH.
.TUESDAY…MOSTLY SUNNY. HIGHS 10 BELOW TO 10 ABOVE…COOLEST
INLAND. NORTHWEST WIND 5 TO 15 MPH.
.TUESDAY NIGHT…MOSTLY CLEAR. LOWS 5 BELOW TO 5 ABOVE.
TEMPERATURE / PRECIPITATION
SEWARD 9 -2 -2 / 0 0 0
GIRDWOOD -3 -15 -4 / 0 0 0
This concludes todays advisory, the next advisory will be on the 7th. Thanks and have a great day.