More than 60 million Americans are facing a flash flood threat after deadly holiday weekend storms swept across the country.

The cooldown after the heat wave is bringing increased chances for more showers and storms and a growing threat of flooding across the tri‑state region.

The threat of widespread flash flooding in the Philadelphia area has diminished greatly, but a flood watch will remain in effect Monday until 8 p.m. Showers and storms Monday were scattered, but any storm could produce localized downpours and lead to the risk of additional flooding,

A powerful line of severe thunderstorms is pushing northeast toward Philadelphia, threatening the area with damaging winds and heavy downpours capable of producing one to two inches of rain per hour.