Flash floods in Texas have killed nearly 90 people, many of them children. Heavy rains fell quickly in the predawn hours Friday in the Texas Hill Country, causing the Guadalupe River to rise 26 feet in just 45 minutes.

( The Conversation) – Texas Hill Country is known for its landscapes, where shallow rivers wind among hills and through rugged valleys. That geography also makes it one of the deadliest places in the U.S. for flash flooding.

A July Fourth weekend deluge in Texas caused catastrophic flash flooding that has killed at least 89 people. Camp Mystic in Kerr County says Monday morning that it is “grieving the loss” of 27 campers and counselors as the search continues for victims of the disaster.