When storms roll in, water rushes downhill fast, gaining speed and force as it moves — often with deadly results.

Three days after tragedy struck central Texas on the morning of July 4 with a deadly flash flood that has killed at least 82 people, a timeline of events has begun to come into focus. An unknown number remain missing, including girls attending a summer camp.

When the precipitation intensified in the early morning hours Friday, many people failed to receive or respond to flood warnings at riverside campsites known to be in the floodplain.