Turnagain Pass

Good morning. This is Wendy Wagner with the Chugach National Forest Avalanche Information Center on Thursday, February 9th 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).

ANNOUNCEMENTS

There is a possibility Alaska DOT crews will be conducting avalanche hazard reduction work along the Seward Highway today. More details can be found at www.5ll.alaska.gov.

Congratulation to Obadiah Jenkins who is our January observer random drawing winner!

Plus, don’t forget tonight Alaska Pacific University is presenting the Winter Wildlands Alliance Backcountry Film Festival again this year and all proceeds benefit the Alaska Avalanche School. Show starts at 7pm at the Grant Hall Theater. More details HERE.

BOTTOM LINE

The avalanche danger is mostly CONSIDERABLE in the backcountry today with pockets of HIGH in areas where the storm continues to linger. Around 2″ of rain and 1-2′ of snow at the higher elevations has fallen in less than 24 hours. High winds accompanied the precipitation and will remain strong. Natural avalanches are still possible and human triggered avalanches are likely today. Travel in avalanche terrain will require expert level route-finding skills and terrain management.

AVALANCHE DISCUSSION

A wet and soggy day in the backcounty yesterday dampened not only the variety of crusts on the surface, but a few outdoor enthusiasts’ spirits as well. Below treeline, natural wet loose, and possibly wet slab avalanches, are suspect to have released last night with an intense shot of heavy rain. Above treeline, natural wind slab and loose snow avalanches are suspect to have released as well.

The recent rain and snow has been falling on a variety of surfaces from a rain crust (now likely melted) to stiff variable wind slab to sastrugi. These hard surfaces were covered with widespread surface hoar on Tuesday; providing a bed surface and weak layer for this storm to add the third ‘slab avalanche ingredient’: the slab. The good news is, the wet conditions were destroying the surface hoar below treeline yesterday. Above treeline there is uncertainty whether the strong winds were able to blow it down or not. Chances are, pockets of buried surface hoar now exist, and could be more widespread than thought.

Today is anCNFAIC Staff day with a wide spectrum of avalanche threats on tap:

Below treeline:

Wet activity is once again a concern today where rain and/or very wet snow has fallen. Though the height of the storm has passed, naturally releasing wet loose and wet/damp slab avalanches are still possible today. The snowpack at the lower elevations continues to harbor dry snow underneath the top 2-6+” (and increasing) of a wet saturated surface. The presence of the dry snow shows that the pack is not yet seasoned to handling rain.

Above treeline:

Storm snow instabilities will be the main concern. These avalanche types will encompass everything from soft slab, wind slab and loose snow avalanches. Decreased snowfall this morning should begin a decrease in activity today. However, the winds are forecast to remain strong and therefore will continue to keep naturals a possibility. Remember, there is bed surface and possible weak layer under this new snow in many locations which will exacerbate the avalanche activity, as well as the ease for a person to trigger an avalanche. Furthermore, there is chance that smaller avalanches could ‘step down’ to the weaker low density snow from last week, creating a larger and more destructive slide.

MOUNTAIN WEATHER

Rain fell below 1000′ yesterday, with an intense pulse last night, which added around 1-2″ of water to the snowpack. Above 1000′, wet, gloppy snow, decreasing slightly in density with elevation, has accumulated to between 1-2′. The easterly winds have been averaging 40mph with 60mph gusts since midday yesterday. The peak of this system is on its way out and skies have already begun to break. Precipitation has decreased and temperatures have dropped a few degrees as well. Yet, easterly winds should continue to blow around 40mph with gusts near 60mph.

Warm cloudy conditions will remain over our area for next couple days with anCNFAIC Staff pulse of moisture for Saturday. It looks like the rain/snow line may descent slowly over the next few storm systems.

CNFAIC Weather Page and the NWS forecast

Kevin will issue the next advisory Thursday morning. If you get out in the backcountry we want to know what you are seeing. Please send us your observations using the button at the top of this page or give us a call at 754-2369. Thanks and have a great day.