Turnagain Pass

Good morning backcountry travelers this is Lisa Portune with the Chugach National Forest Avalanche Information Center on Sunday, January 24th 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).

WEATHER ROUNDUP

Despite no new snow in the last four days in Turnagain Pass, the weather has been just about perfect…sunny skies, light winds, and mountain temps in the 20’s since Wednesday. Yesterday ridgetop winds were light, averaging 10-15mph out of the east and southeast, while mountain temperatures ranged from the mid 20’s to low 30’s. There was, however, a 15 degree inversion yesterday with sea level temps in the single digits and teens. As of 4am this morning, ridgetop winds are averaging 5mph out of the southeast with clear skies overhead. We still have an inversion this morning with temps currently ranging from 26F at 3800 feet to 6F at sea level. A series of shortwaves in the gulf may bring cloudcover today and tonight, but no precip is in the forecast. Today, mountain temps will remain in the 20’s while ridgetop winds will be light out of the southeast. We could however get some stronger winds on Seattle Ridge closer to Turnagain Arm.

-3800′ Sunburst Wx Station-

recorded light easterly winds yesterday averaging 10-15mph. The current temp is 26F (2 degrees warmer than yesterday) with winds averaging 5mph out of the southeast.

-2400′ Seattle Ridge Wx Station-

recorded light southeasterly winds yesterday averaging 10-15mph. Winds are currently averaging 5mph out of the southeast.

-1800′ Center Ridge Wx Station-

recorded no new snow in the last 24 hours. The current temp is 26F (8 degrees warmer than yesterday) with a total snowpack depth of 65 inches (1 inch of settlement since yesterday).

The weather forecast for:

INCLUDING…WHITTIER…SEWARD…GIRDWOOD…MOOSE PASS

500 AM AKST SUN JAN 24 2010

.TODAY…MOSTLY CLOUDY. HIGHS IN THE MID TEENS TO LOWER 30S…

COLDEST INLAND. LIGHT WINDS. NEAR SEWARD…NORTH WIND 15 MPH

INCREASING TO 25 MPH IN THE AFTERNOON.

.TONIGHT…MOSTLY CLOUDY. LOWS 10 TO 25 ABOVE…COLDEST INLAND.

LIGHT WINDS EXCEPT NORTH 15 TO 20 MPH NEAR SEWARD. NEAR WHITTIER…

LIGHT WINDS BECOMING WEST 15 TO 30 MPH.

.MONDAY…MOSTLY CLOUDY. HIGHS IN THE LOWER 20S TO LOWER 30S…

COLDEST INLAND. LIGHT WINDS EXCEPT NORTH AND WEST 15 TO 30 MPH NEAR

SEWARD AND WHITTIER.

.MONDAY NIGHT…PARTLY CLOUDY. LOWS 10 TO 25 ABOVE…COLDEST

INLAND. LIGHT WINDS EXCEPT NORTH AND WEST 10 TO 20 MPH NEAR SEWARD

AND WHITTIER.

TEMPERATURE / PRECIPITATION

SEWARD 30 24 30 / 0 0 0

GIRDWOOD 20 15 19 / 0 0 0

AVALANCHE DISCUSSION

Today the avalanche hazard is rated LOW with pockets of MODERATE danger on slopes steeper than 35 degrees. Snow conditions currently consist of 1-2 feet of settled powder on top of a slick crust that formed in early January. Although I would expect any avalanches triggered to be small and not propagate very far, pockets of sensitive soft slab 1-2 feet deep do exist on steep slopes and were reactive as recently as yesterday.

A few reports of human-triggered avalanches have trickled in the last few days. A skier kicked off a small 1 ft. deep soft slab that slid on a hard bed surface on Cornbiscuit on Thursday. Yesterday afternoon several folks noticed a new skier-triggered soft slab on the west face of Magnum at 2500 feet. This slide was estimated at 30-50 feet wide, 1-1.5 feet deep, and 200 feet long. CNFAIC Staff than sluffing on 40+ degree terrain, no CNFAIC Staff recent avalanche activity has been reported. Folks are skiing and riding big lines without incident for the most part.

Yesterday Jon and I toured up to the Sunburst weather station at 3800 feet via Taylor Pass. Our snowpit stability tests at this elevation produced clean, moderate shears 1 ft. down on slick hardpacked snow (CTM14-15 Q2’s). (Check out our newest video by clicking on the button at the top of this page.) CNFAIC Staff recent stability tests produced clean, hard shears on the buried crust (CTH21-23 Q2’s) indicating better bonding in CNFAIC Staff areas. We observed no obvious signs of instability, and ski cuts did not trigger any soft slabs. CNFAIC Staff than a few isolated pockets, our current snowpack lacks the energy to propagate a fracture, but that could quickly change with the addition of new or windblown snow. The fact is we have a significant buried weak layer that could become active again with more of a snowload.

If big lines are on your agenda, evaluate the snow and terrain carefully. Travel one at a time, watch your partner, have an escape route, avoid terrain traps, and have a rescue plan with all the rescue equipment needed for companion rescue. In the backcountry you are the rescue party. Always remember that safe backcountry travel requires training and experience. You control your own risk by choosing where, when, and how you travel.

**Do you or any of your friends have an opinion on whether or not there should be current avalanche information available for the Front Range section of Chugach State Park? If so, please take 5 minutes to contribute to the process by filling out the survey below. This information will be used to determine if such a program is feasible or not. Only one survey per computer is allowed, but anyone can fill it out if an un-used computer is accessed. Click here to take survey

I 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.