A tornado watch has been issued across a large portion of the Northeast, including major metropolitan areas from Delaware to New York City and upstate New York, as the region prepares for multiple rounds of severe thunderstorms on Tuesday afternoon and evening.

The severe weather outlook follows a period of heavy rainfall over the weekend in New York City, which experienced significant street flooding, highlighting the region's vulnerability to intense storms. The current forecast predicts not only the possibility of tornadoes but also damaging wind gusts reaching up to 70 mph, large hail, and rainfall rates exceeding one inch per hour.

Multiple tornado warnings were issued in New Jersey on Tuesday afternoon, and at least two tornadoes have been reported, one in northeastern Pennsylvania and another in northwestern New Jersey. The primary concern for a broad swath of the Interstate 95 corridor, from Philadelphia through New York City and into Connecticut, is the threat of dangerous flash flooding.

Further west and south, severe thunderstorm watches are in effect for areas including Kentucky and Pennsylvania, with cities like Charleston, West Virginia; Cincinnati, Ohio; and Pittsburgh, Pennsylvania, potentially impacted. Flooding is also anticipated in Tennessee.

In anticipation of the severe weather, more than 1,900 flights have been canceled nationwide on Tuesday. Airports in the New York City metropolitan area, Philadelphia, and Washington, D.C., are experiencing the most significant disruptions, with ground stops implemented at airports in New York City, D.C., Boston, and Baltimore.

New York City Mayor Zohran Mamdani has urged residents to take precautions, advising them to seek shelter indoors during thunder, heavy rain, or strong winds. He also stressed the importance for those living in basement apartments to know their escape routes and be prepared to move to higher floors if flooding begins.

Meanwhile, severe weather also caused dangerous flooding in Des Moines, Iowa, on Monday night. The Des Moines Police Department reported that nearly two dozen vehicles were stranded and five individuals required rescue. Police Chief Michael McTaggart emphasized the need for drivers to slow down, monitor changing conditions, and prioritize safety.

The widespread severe weather impacting the Northeast and Midwest underscores a period of heightened atmospheric instability. Forecasters are closely monitoring the development and movement of these storm systems, with continued alerts expected for affected regions as the situation evolves.