Flash flooding is weather’s No. 2 killer, claiming more lives than anything but heat, so it’s important to understand what causes it and how to stay safe.

The main thing about a flash flood is its speed. By definition, the rushing waters begin within six hours after an intense storm—and often within three hours, which is why it’s called a flash.

The force of a flash flood can roll boulders, rip trees out of the ground, and destroy buildings and bridges. True to their name, these floods occur suddenly – within a few minutes or hours.

The FOX Forecast Center said the first Flash Flood Emergency was issued near San Angelo after 12-15 inches of rain was reported and flooding was ongoing.

Big flash floods would mark a particular year, such as 2009. But recently, just as scientists predicted, human-caused climate change has produced bigger flashes that are more frequent, more ...

During a flash flood, natural channels and ditches can quickly fill with water, becoming dangerous torrents. Stay clear of these areas. Imagine them as hidden traps, ready to ensnare the unwary.

Flash floods also swept away dozens in Afghanistan in July, less than three months before thousands were killed by a powerful 6.3 magnitude earthquake that struck the western part of the country.

As flash flooding hits the Northeast, here's what to know about the dangerous weather phenomenon.

3 things to survive a flash flood in a car 1. Don't let the car fill up before getting out ABC News' chief national correspondent Matt Gutman demonstrates how to safely escape a car during a flash ...

Flash flooding from torrential rains left five people dead and four others missing in West Virginia over the weekend. The Wheeling and nearby Triadelphia and Valley Grove areas were the most affected.

Flash flooding possible in New Jersey Persistent and "quite serious" downpours drenched portions of Ohio, Pennsylvania and West Virginia on Sunday, Porter said, and the same system that produced ...