#Hiker dies in Grand Canyon in triple-digit heat

A 57-year-old woman died on an 8-mile hike in Grand Canyon National Park on Sunday, when temperatures topped 100 degrees, park officials said.

Park rangers got a call about a hiker in distress at 6:30 p.m., and when the woman was found in a remote area of the park at 1 a.m. she was dead, the National Park Service said in a statement.

She was on an 8-mile hike in the Tuweep area of Arizona, which is described as a remote region.

The heat was well over 100 degrees Sunday. A cause of death is under investigation, but the park warned of the dangers of extreme heat in a statement Monday.

A large part of the Southwest, including the Grand Canyon area, was under an excessive heat warning Monday. The temperature in Phantom Ranch was 114 degrees, the National Weather Service said.

The Grand Canyon is under the excessive heat warning until 8 p.m. Wednesday.

On Monday heat warnings covered parts of the Southwest, in California, southern Nevada and Arizona, according to the weather service.

Heat can be deadly on hikes, and heat-related conditions are the most common cause of death due to weather in the U.S., the Environmental Protection Agency and others warn. An average of 702 people die from heat-related illnesses every year, according to the Centers for Disease Control and Prevention.

A 14-year-old boy and his stepfather died last month as they hiked in Big Bend National Park in Texas on a day when temperatures were 119 degrees. The boy fell ill, and his stepfather died after he crashed his car trying to get him help, park officials said.