Hiking canyons can quickly turn deadly when storms hit – what you should know before going in

Following a deadly flash flood at the Grand Canyon that killed at least two hikers and left a third missing, a geologist explains how narrow canyons can flood even when the rain is falling miles upstream, out of sight of anyone below.

The piece cites a 2018 flood in Israel's Tzafit Canyon that killed 10 recent high school graduates, and notes arid ground often forms crusts that repel rather than absorb water, worsening surface flooding.

Practical advice follows: check weather forecasts for the surrounding area, not just the trailhead, talk to rangers before entering, carry a flashlight and whistle, and move to higher ground immediately at signs of rising or muddy water, since flash floods studied nationally average roughly three and a half hours but some run past 48.

The full dispatch is available from the source below.