BOZEMAN, Mont. (AP) — The Gallatin National Forest Avalanche Center has issued a backcountry avalanche warning for its whole advisory area.

The center said early Wednesday that the danger for a slide is high in the Bridger, Gallatin and Madison Ranges, the Lionhead area outside West Yellowstone and the mountains around Cooke City.

It cites heavy snowfall that's created instability and the potential for natural avalanches.

The center advises people not to travel in areas at risk for slides.

The warning lasts until 6:30 a.m. Friday.