Will New York City ever lose its status as most populous city in the US?

[Sol]

The only thing which I think could potentially displace it in the medium term would be climate change. Maybe I'm optimistic, but I suspect NYC, at least Manhattan, is too essential to the machinery of present-day capital for sea level rise to have much of an impact. Much of the city is also more elevated than you might expect, so even in most projections the vast majority of the city is above water.

That said, it's worth noting that the portions of NYC most at risk from climate change are the low-lying areas around Jamaica Bay, which also are relatively disadvantaged socioeconomically and thus may not get an effective response from the powers that be. (Hopefully this will not actually be the case!).

Climate Change also does mean more variance/extreme weather, which means more frequent hurricanes in particular, but other plausible competitors to NYC have similarly threatening issues -- high temperature risks in the South and Midwest, hurricanes anywhere along the Atlantic or Gulf coasts, flooding in Chicago, fires on the west coast, etc. Everybody is going to have elevated risks of horrible natural disasters.