The advisory is for areas above 6,000 feet and they're calling for 4+ inches of snow. Get the Winter Weather Advisory details here:

The National Weather Service in Great Falls has issued a Winter
Weather Advisory for elevations above 6000 feet for snow and
blowing snow... which is in effect from 11 PM this evening to 5 PM
MST Wednesday.

Snow accumulations: 4 to 7 inches of snow above 6000 feet.

Locations affected include: Bozeman Pass... Targhee Pass... West
Yellowstone... Ennis... Raynolds Pass... Monida Pass

Timing and impacts: snow is expected after midnight Tuesday
night through Wednesday afternoon. Areas of blowing snow are
expected after midnight tonight through Wednesday morning with
visibilities reduced to one half mile or less at times.

A Winter Weather Advisory for snow and blowing snow means
visibility will be limited due to a combination of falling and
blowing snow. Use caution when traveling... especially in open
areas.

For specific Road and travel conditions in Montana... dial 5 1 1.

Winter Weather Advisory for Gallatin County