A flash flood is a rapid rise of water along a stream or in a low-lying urban area, the National Weather Service said. Flash flooding can result from slow-moving thunderstorms, from numerous thunderstorms that develop repeatedly over the same area, or from heavy rains associated with tropical cyclones.

Flash flooding has been in the spotlight in the last week, with several record breaking flood events occurring nearly back-to-back across the country. CNN’s Tyler Ory explains why they’re becoming more intense .

With rain coming down so fast, storm drains couldn't handle the deluge of water. On Interstate 93 in Quincy, all were lanes closed at one point because of extreme flooding during rush hour. At least five cars were stuck on the highway until the water receded.

As crews search for missing people after flash floods killed at least 120 in Texas, cities across the U.S. grapple with rising flood waters.

Back-to-back flooding disasters in recent years — in Texas, New Mexico and Kentucky, among many others — have showed that preparing for flash flooding is a new necessity as the planet warms.

Thursday's rain was a highly localized event. The highest impact was only felt over a 5-to-10 mile area south of Boston.