Avalanche Advisory Archive Pre-2016

Date Issued:2016-02-20
Danger:2
Trend:3
Probability:4
Size:2
Problem:3
Discussion:

The National Weather Service Forecasts-

TODAY...SNOW...MIXING WITH AND CHANGING TO RAIN THROUGH THE
MORNING. SNOW ACCUMULATION 1 TO 2 INCHES. SNOW LEVEL RISING TO
700 FT IN THE AFTERNOON. HIGHS AROUND 40. LIGHT WINDS BECOMING
SOUTHEAST 10 TO 20 MPH IN THE AFTERNOON.

TONIGHT...CLOUDY. CHANCE OF RAIN. LOWS AROUND 35. EAST WIND 15 TO 25 MPH WITH GUSTS TO 35 MPH.

SUNDAY...RAIN LIKELY. HIGHS AROUND 42. EAST WIND 15 TO 25 MPH.

Temperatures started quite cold yesterday. The Mt Roberts Tram had a low of 18f. Currently its 29f. Eaglecrest started much the same with a low of 15f yesterday at mid mountain. Currently its 31f at the base area, 27f at mid mountain and 26f on top.

Overnight we received a little new snow. This started off at about 1am. Eaglecrest and the tram both warmed by over 11f degrees yesterday. 9f degrees of the 11f degree warming occurred before the snowfall started. This should help with bonding slightly.

We received 3.6mm of precipitation at the Mt Roberts Tram summit leaving us 4cm of new snow. Eaglecrest was somewhat the same with 4.6mm of precip and closer to 7cm of new snow. This is not an overwhelming amount of new snow.

Recognize this new snow was still relatively cold and wont bond all that well to the old icy snow surface.

Remember for the last few days we have had a little wind leaving isolated very shallow slabs high in our starting zones. This new snow came in with some wind last night on Douglas Island. Eaglecrest is showing winds from 12-25 mph out of the ESE, which can transport a lot of new snow.

Be aware of windslabs today on Douglas Island near summit and ridgeline. These slabs may be sensitive with some warming during the snowfall and windloading on top of that.

Bottom Line: Avalanche danger is MODERATE today. Natural avalanches are unlikely yet human triggered avalanches will be possible in windloaded areas.

Recognize that anything that gets triggered will run fast with this slightly colder dryer snow on the ice crust in place. Be aware that self arrest could be difficult due to the base layer. Avoid exposures over cliff and rock and use a little extra caution.

Temperatures are forecast to warm up another several degrees from today into tomorrow. Forecast models snow light precip with no more than an inch or two of snow for any 12 hour period. This should keep danger at moderate. It may increase a little depending on winds and temperatures as well as how this snow is currently bonding.

Look at the old snow new snow interface to see how bonding is coming along. This will give you a better picture of overall stability.

Tip:

LIVE TO RIDE ANOTHER DAY!

Eaglecrest is hosting an Backcountry Safety Awareness and Companion Rescue Course Saturday March 5th from 8:30am-3:30pm.

This course is free and sponsored by the Department of Public Safety.

During this day long course you will learn about avalanche terrain, weather, and stability assessment tests. You will also learn about Avalanche Rescue as well as transceiver, probe and shovel use.

Please share this offering with your friends. Lets all do out part to maintain a safe backcountry community.

For more information or to sign up please email Tom.Mattice@juneau.org