I-90 between Spokane and Billings When can expect snow?

Check the forecasts. We were there last week with great weather, and 3 years ago at the same time we had the first snow of the season. Earlier is better.

must tell you I am 70 years old and I remember way back in my high school days a teacher told us he took a group of kids to camp in the area you are talking about and he said it snowed on them the first morning they were there. He was saying it was in July and he and the guys never thought for one minute it would snow up there in July. just goes to show you, it can snow any day of the year up there. It's amazing how I can remember that teacher and I can not tell you what I had for breakfast this morning

Lookout Ski area on the state border appears to open in the 2nd half of November.

Earliest? August... no kidding

Normal, late Nov can be dicey.

But if it snows, it will not stick around for long, stop someplace and wait it out.

You can experience snow about any time of the year in higher elevations. But generally speaking the weather will not be turning until the end of October or November.