Good morning backcountry travelers. This is Wendy Wagner with the Chugach National Forest Avalanche Information Center on Monday, February 28th 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).
The avalanche danger is MODERATE on steeper slopes for triggering a wind slab. These are most pronounced in wind loaded steep rocky areas and cross loaded gullies. There is also a MODERATE danger for a slide to break into deeper faceted snow.
Not many folks were out and about Sunday enjoying the sun, not to mention the severely wind damaged slopes. No new avalanche activity was reported. The winds remained light yesterday with no recent wind drifting observed.
Wind slabs remain today as the primary concern. Although many of the slopes have been scoured down to old tracks, crusts and facets, wind loaded areas still exist. I expect these wind slabs to be very hard and stiff in most locations and fairly stubborn to trigger. The possibility of releasing a wind slab will be most pronounced in steeper rocky terrain and in cross loaded slopes and gullies.
The secondary concern is an avalanche breaking into old weak faceted snow, potentially producing a much larger slide. Most prone are areas with an average snow cover of less than 2 meters, especially steeper slopes that have been wind loaded. These hard slabs are likely difficult to trigger but if you do can be unmanageable.
Sunday, skies were clear with temperatures in the single digits. The winds remained calm, only gusting into the 20’s from the northwest. Overnight temperatures climbed to around 10F where they sit currently and should increase into the upper teens today. Skies will be sunny again with winds forecast to remain light with gusts from the northwest in the 20’s on the ridgelines. We are currently under a large scale high pressure system bringing clear sky conditions, this looks to extend into the end of the week. No new snow is in the forecast for several days…
ANNOUNCEMENTS An APU student is conducting a survey on backcountry skiing group dynamics. Click on the link to participate in research on avalanche safety. Click here to take survey
The Forest Service is installing winter use bridges across Granite creek in Turnagain Pass. Be aware of an ice road from the Lyon creek bridge south towards Johnson Pass on the West side of the highway. Heavy equipment will also be used in the area.
Jon will issue the next advisory tomorrow morning at 7am. If you get out in the backcountry give us a call at 754-2369 or send us your observations using the button at the top of this page. Thanks and have a great day.
The NWS weather forecast for:
WESTERN PRINCE WILLIAM SOUND-
500 AM AKST MON FEB 28 2011
.TODAY…SUNNY. HIGHS IN THE LOWER TO MID 20S. NORTH TO WEST
WIND TO 15 MPH. NEAR SEWARD AND WHITTIER…NORTH AND WEST
WIND 15 TO 30 MPH WITH GUSTS TO 40 MPH IN THE MORNING.
.TONIGHT…CLEAR. LOWS ZERO TO 10 ABOVE INLAND AND IN THE
TEENS ALONG THE COAST. NORTH TO WEST WIND TO 15 MPH EXCEPT
15 TO 25 MPH WITH GUSTS TO 35 MPH NEAR SEWARD AND WHITTIER.
.TUESDAY…MOSTLY SUNNY. HIGHS IN THE 20S. NORTH TO WEST
WIND TO 15 MPH. GUSTS TO 30 MPH NEAR SEWARD AND WHITTIER
IN THE MORNING.
.TUESDAY NIGHT…MOSTLY CLEAR. LOWS 5 TO 20 ABOVE…COLDEST
INLAND. VARIABLE WIND TO 10 MPH EXCEPT NORTH WIND 15 TO 25 MPH
.WEDNESDAY…SUNNY. HIGHS IN THE 20S. NORTH TO WEST WIND
TO 15 MPH EXCEPT NORTH WIND 20 TO 30 MPH NEAR SEWARD.
.WEDNESDAY NIGHT…CLEAR. LOWS 5 TO 15 ABOVE.
.THURSDAY…MOSTLY SUNNY. HIGHS IN THE 20S.
TEMPERATURE / PRECIPITATION
SEWARD 24 16 28 / 0 0 0
GIRDWOOD 20 6 24 / 0 0 0
WEATHER STATION SUMMARY for Turnagain Pass:
-3800′ Sunburst Wx Station-
Temperature 11 degrees. NW winds 5-10mph, gusting to 20.
-2600′ Seattle Ridge Wx Station-
Temperature 10 degrees. NW winds 5-10mph gusting to upper 20.
-1800′ Center Ridge Wx Station-
Temperature 5 degrees. No new snow.