Well the word nor is a coordinating conjunction, (or, and, nor, for, but, or, yet, and so). I believe the British have more but those are the ones Americans use
This mean they joing two words or clauses of equal importance.
The difference between “or” and “nor” is they both present alternate ideas but “nor” presents an alternate negative idea
Yet seems by defintion to be better
Yet is used as a coordinationg conjuction to connect words or clauses that are contrary ideas that follow logically.
While it probably would pass a grammar test, to me it’s not the conjunction but use of the word “fell” that mucks it up
When one says the snow fell, it implies the snow is over, at least for a bit. If I wanted to say the snow fell, one can infer the snowfall is done with otherwise I’d use the word fall.
If I wanted to use both I’d use “and” as my conjunction
For example, the snow fell all night AND continues into the morning. This says the snowfall was over for the night.
So if it fell it has to be done with in relationship to something else. In totality or in my above example as connected to an event that’s over, such as night.
Since something that fell and is now falling again, yet serves that purpose.
That’s the nice thing about grammar it’s possible to find some kind of fault with most things.