Red Lodge is of course a cool town. Skiing can be great or so-so. Not alot of challenging terrain but if you are an intermediate you'll have more than enough to choose from.
Bridger Bowl is great. I call it "little jackson" as the ridge terrain is comparable to Jackson Hole and has some of the best in bounds terrain around. But you'll need avy gear to access it. On powder day or weekend it can be a complete gong show though. Good value for your $$
Big Sky is not what it once was and is getting crazy expensive and ultra corporate. Everything from parking to food to lift tickets have gone nuts. More terrain than you can ski in a week. That's a good or bad thing IMO. I dont even bother going there until April when the deals start showing up and you could have a mid winter powder day or you could be skiing corn in 50 degrees and sun.
Whitefish has a cool vibe and on a good year its one of the best in MT IMO. They've started out a little slow this year but have been getting some leftovers of the storms hitting BC and the PNW lately. Cost isnt bad and the town is super fun. Beware of the fog though.
If you are willing to travel north a bit, Schweitzer near Sandpoint ID is IMO one of the best values in skiing. Its a complete sleeper resort that should get alot more pub than it does, but that's not a bad thing.
I haven't skied Discovery or Lost trail but I have heard good things.
I can see how Great Divide near Helena can be fun but I've never been there in good conditions, not sure I'd make it a destination spot though.
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I was just at Big Sky last week and they had plenty of snow. For this early in the season they had more of the mountain open than in the past. Their new Ramcharger8 lift is now open and that thing is sweet! .
Screw that.. No one should ever be forced to ride a chairlift, under a bubble with 7 people from Texas..