In what experts call "Flash Flood Alley," the terrain reacts quickly to rainfall steep slopes, rocky ground, and narrow riverbeds leave little time for warning.

This part of Texas is one of the most flood-prone areas in the entire world. Here’s a look at some of the region’s worst floods on record.

Tragedy has struck in Texas with scores dead in massive floods. Sadly, flooding deaths are not uncommon in the U.S. Flooding has caused an average of more than 125 deaths per year in the United States over the past few decades, according to the National Weather Service, and flash floods are the nation’s top storm-related killer.