Visitors to Grand Canyon National Park are being warned of dangerous heat conditions early next week after a series of recent heat-related deaths raised concerns about safety in the park.
The U.S. National Weather Service has issued an extreme heat watch from Monday through Tuesday evening for lower elevations of the canyon, where temperatures are forecast to exceed 110F and could reach as high as 112F.
Park officials are urging hikers to avoid strenuous activity during the hottest hours of the day and to stay out of the canyon between 10 a.m. and 4 p.m. whenever possible.
The warning follows several fatal incidents linked to extreme temperatures in the Inner Canyon.
According to the National Park Service, three hikers died in separate incidents during the past week after experiencing symptoms consistent with heat-related illness.
A 72-year-old man died along the South Kaibab Trail on June 12.
On June 16, a 67-year-old man and a 68-year-old woman were found deceased on the North Kaibab Trail, an investigation that remains ongoing.
Officials said all three hikers were on trails where midday temperatures can exceed 109F even in shaded areas.
Despite rapid emergency responses and aerial support, responders found all three individuals dead upon arrival.
Earlier this month, an 18-year-old visitor also died after experiencing heat-related symptoms in the park.
Weather officials noted that conditions at the canyon rim can be significantly cooler than temperatures experienced deeper inside the canyon, creating deceptive hiking conditions for visitors.
Authorities said the region is approaching one of the hottest periods of the year before seasonal monsoon rains typically bring some relief later in the summer.
The extreme heat is part of a broader weather pattern affecting much of the western United States.
Heat watches and advisories have been issued across parts of Arizona, Oregon, California, Texas, Alaska, Puerto Rico, Florida, Arkansas, Oklahoma and New Mexico.
In northern Arizona, evacuation orders were issued near Oak Creek Canyon after the Pocket Fire burned roughly 500 acres north of Sedona.
Fire crews from multiple agencies are working to contain the blaze as hot, dry weather and low humidity increase wildfire risks across the region.