[TylerE]

I guess the issue is that the yards where the trains are stabled are all above ground. If you can't get the crews to them, inspect, and operate them safely, you can't get them in the tunnels. Subway trains are all also 3rd or 4th rail powered, so I can see how lots of (effectively) standing water makes people nervous.

The mitigation I suppose would be to get them underground in advance, and when/if the snow hits you just run with what you've got.

[jrockway]

In NYC we actually have a bunch of yard capacity that is completely underground, and then a bunch of other yards that are covered (like condos built on top). Typically the snow service plans involves stacking as many trainsets as possible on the express tracks, while service runs on the local tracks. There are a ton of extra express tracks on the network (because the IND had what appears to be unlimited money when building their system), so capacity doesn't suffer a ton.

Honestly, in the 12 years I've lived in NYC, there have really only been 2 or 3 nasty snowstorms. Generally things ran OK except the one time Cuomo freaked out. (Hurricane Sandy was pretty nasty, of course. Rain and storm surge are much worse than snow here.)