Storms prompted flash flood warnings across the New York City metropolitan area Monday night, with photos showing severe flooding across the city and in parts of New York state and New Jersey. Heavy rain moved through the region Monday,

A flood watch has also been issued in Washington, D.C., while the Midwest also has the potential for flooding.

The subway system, which is more than a century old, is relied on by millions of passengers every day and weaves the city into a cohesive network.