A heat advisory is in effect for the New York City area Wednesday and Thursday, with feels-like temperatures expected to exceed 100 degrees as more storms threaten the forecast. Air quality is also a concern for vulnerable groups.

NYC could be in play for another heat wave this week, with the potential for more heavy rain, storms and flash flooding due to the hot and humid conditions.

Heavy rain inundated the region with flash flooding that stranded vehicles in roadways, closed subway lines and led to the declaration of states of emergency.

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.

Video shows lightning striking One World Trade Center in Lower Manhattan, illuminating the city skyline amid a severe thunderstorm.

Lingering showers were forecast for the New York City area, but heavy rain and threats of flash flooding were shifting south on Tuesday.

As the skies opened up over New York City, torrents of rain transformed bustling streets into rivers, leaving residents grappling with an unexpected deluge.