The northeastern United States is facing severe weather, including flooding downpours and strong winds. In New York City, travel disruptions are mounting as streets and subway stations fill with rain.

Hundreds of flights were canceled and delayed at airports across the region, including John F. Kennedy International Airport and Logan International Airport.

Central Park had some of the heaviest rainfall in the area with 3.28 inches by noon, according to AccuWeather Senior Meteorologist Dave Dombek.

NYPD and FDNY respond to stuck vehicles on flooded streets on Monday morning. (Photo/@NYPS33Pct)

"The area was hit by a very strong, potent system," Dombek said. "The air mass came up from the Gulf states and combined with air coming off the Atlantic Ocean, so it had a lot of moisture with it."

Many areas in and around New York City experienced thunder and at least 3 inches of rain over a six- to eight-hour period, which created prime conditions for flooding and morning commute travel delays. Pictures and videos of rain leaking into underground subway stations flooded social media as people headed to work Monday morning.

Apparently it's also raining inside the subway... pic.twitter.com/MOzGdYHRKl — Morgan Philbin (@morgan_philbin) April 16, 2018

The heaviest rain shifted out of the city on Monday afternoon. A few showers will move through the city on Tuesday, but should not be enough to spur another round of major flooding.

The system unleashing the torrents of rain also soaked parts of New England, leading to poor conditions for those running in the Boston Marathon.

Several Boston Marathon runners reportedly started to experience symptoms of hypothermia due to the rainy and chilly conditions.

Multiple runners are starting to get hyperthermia along the @bostonmarathon route in #Wellesley.
Wellesley Fire has made a request to @MassEMA for a warming bus at Central Street and Weston Road -- according to @WellesleyPolice. pic.twitter.com/z7k3FgRv5Q — Jenn Zarate (@JZarateNews) April 16, 2018

Severe flooding caused the closure of northbound lanes on the Henry Hudson and 178 Street. (Photo/NYPD33Pct/Twitter)

Thank you all for the support. I unfortunately had to drop out near the 30km mark due to severe hypothermia. I'm fine now, much thanks to random people in Newton who welcomed me into their home and took care of me until the medics arrived. On to the next one. — Ruben P. Sança 🇨🇻 (@RubenPSanca) April 16, 2018