This week came a harsh reminder of just how powerful Mother Nature can be and that it’s possible to drown in the desert. The unthinkable can happen as a result of flash flooding.

Massive thunderstorms and rain showers resulted in flash flooding in southern Utah causing two tragic incidents this week.

An entire group of seven hikers, all in their 40s and 50s, were killed in a steep slot canyon as water came rushing down. Six have been recovered and another missing. In another incident further south, a van full passengers was washed down stream resulting in the deaths of 12 people.

In the story from Zion, the hikers received a permit to hike the Keyhole Canyon just hours before a flash flood warning was issued, and park officials had no time to warn the hikers, according to reports.

This narrow slot canyon is as tight as a window in sections and hundreds of feet deep as evidenced by the video below. And late summer and fall are the prime seasons for flash floods. Craig Childs, author of The Desert Cries who has spent a lot of time in the southern Utah deserts, explained to NPR how quickly conditions can change. 

“We’ve had especially heavy rainfall summer,” he said. “And so you get these big thunderstorms this time of year that can drop a lot of water in one place. And then that water just takes off and heads downstream.”

It’s not difficult to see how rising flood waters and debris could make for a deadly scenario. After all, the canyon’s themselves were formed by the sudden rush of water and stones that carved its way through the rock. Childs said he’s watched many flash floods in the desert occur and has even found himself on the receiving end.

“They’re extraordinary events, just so much water being shoved through the desert all at once, picking up everything, picking up trees and boulders,” he said. “You just want to be in the right place, not in the wrong place.”

For a look at what kind of debris washes into a slot canyon, check out the video below of two hikers prying themselves free. The first is a repel on the Keyhole Canyon where seven hikers have been lost.