Avalanche specialist Stan Bones will give a free presentation about early-season backcountry snow and avalanche conditions in Northwest Montana at the Flathead National Forest office in Kalispell, 650 Wolfpack Way, on Tuesday, Dec. 13, from 6:30 to 9:30 p.m.

The presentation will focus on the weather in Northwest Montana, typical weather patterns, Web sites that display current mountain weather conditions and forecasts, and how to interpret the data and forecasts.

Bones will discuss last season's conditions and how the weather set the stage for the fatal avalanche incident on Doris Ridge in January 2011. He will also review how avalanche advisories are formulated, the North American Avalanche Danger Scale and the new local advisory format.

No registration is needed for this question-and-answer format presentation. For more information, call the Flathead National Forest at 758-5284 or visit online at www.fs.usda.gov/flathead.

Avalanche advisories are available online at www.fs.usda.gov/flathead and www.glacieravalanche.org or by calling 257-8702.