I was there in March 2025, and there was hardly any snow (but that was a very warm winter for Norway, and late in the season).
I was just there again in February 2026, and the snow was great! It snowed probably 30cm or so the few days before we arrived, and then continued while we were there. Fresh powder the whole weekend =)
Neither of these visits did I take the funicular to the very top (Gaustatoppen) because it was cloudy at the top (and I really want to see the view from up there - there's always next winter). On a clear day, you're able to see 1/6 of Norway from Gaustatoppen!

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