Posted:
Jan 18, 2010 @ 12:00 am

Martin Luther King Day 2010 Avalanche Advisory

Good morning, this is Dudley Improta with the West Central Montana Avalanche Center’s avalanche advisory for Martin Luther King Day, 2010.

Current Avalanche Danger
On slopes steeper than 35 degrees and on all aspects at elevations above 5000 feet, the avalanche danger is MODERATE. Natural avalanches are unlikely, human triggered avalanches are possible. On other terrain within the advisory area the avalanche danger is LOW.

Weather and Snowpack Analysis
The MODERATE avalanche danger is related to a surface hoar layer that is buried about 40cm (16”) from the surface. On some locations within the advisory area this layer is still reacting cleanly to stability tests. If you are recreating on steep slopes above 5000′ it would be prudent to check for instabilities in the top couple of feet.

The area received a very modest amount of snow over the weekend. We had rain up to about 5500′ in elevation and small amounts of dense snow above the rain level.

The depth hoar that formed in early December is still around on slopes that haven’t already avalanched, but it is not reacting to stability tests.

Moderate temperatures at elevation (anywhere from the high 20’s to the low 40’s) are helping stabilize the snowpack.

Weather Forecast and Avalanche Outlook
The unsettled weather pattern is expected to continue this week. The Weather Service actually used the dreaded words “El Nino”. We should see some precipitation each day, but amounts are expected to remain low. Snow levels should be approximately 3000 feet. One word of warning, if it does start to rain on the snow pack when you are recreating or working in the mountains; you should stay off steep slopes. The immediate effect of rain would destabilize the current conditions. Rapidly-added weight almost always means rapidly-rising avalanche danger.

Expect our avalanche conditions to remain the same until we see significant changes in the weather.

Steve Karkanen will post the next advisory on 1/22/10.

If you get out and see avalanche activity or want to send us quick snow observations, send us a note at [email protected] or call us at 406-530-9766. 530-9SNO.

For Beacon Park information go to mslaavalanche2.wpengine.com/beacon_training.php.

READ FULL ADVISORY  

This information is the sole responsibility of the Forest Service and does not apply to operating ski areas. The avalanche danger rating expires at midnight tonight but the information can help you make a more informed decision regarding travel in avalanche terrain for the next few days.

Our advisory area includes National Forest System lands in the Bitterroot Mountains from Lost Trail Pass north to Granite Pass, the Rattlesnake Mountains north of Missoula and the Southern Swan and Mission Mountains near Seeley Lake, MT. Avalanche information for the Lookout Pass/St. Regis Basin area is available from the Idaho Panhandle Avalanche Center.