Texas Hill Country, where much of the flooding took place this time, is often referred to as “flash flood alley.” It's home to steep terrain and a lack of vegetation that creates a perfect storm for waters to rise quickly.

Texas Governor Greg Abbott said Tuesday that many of those who are not accounted for were staying in state’s Hill Country but did not register at a camp or hotel.

Search and rescue operations in Texas continue after heavy rainfall overwhelmed the Guadalupe River, sending floodwaters roaring through the area.