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.

The storms that battered the Hill Country for the last four days began to lighten up, although isolated pockets of heavy rain were still possible.

As Central Texas reels from flash floods that killed over 100 people this weekend, questions are sharpening about whether officials could have done more to avert the tragedy – both in the decades leading up to the disaster,