WHEN THE wind is up, and the clouds keep circling back, and the weather in central Norway can’t seem to decide what kind of August it is, it can be very difficult to see Snøhetta.

That would be Snøhetta the mountain, not the New York– and Oslo-based architecture and design firm, a freewheeling international collaborative responsible for the new Norwegian currency (going into circulation in 2017) and the ongoing redesign of Manhattan’s Times Square (slated for completion by the end of the year), among other projects. A few...