20-year-old hiker shares Grand Canyon warning

Extreme Heat Warning

from THU 10:00 AM MST until MON 8:00 PM MST, West Pinal County, East Valley, Gila River Valley, Deer Valley, Scottsdale/Paradise Valley, Superior, Rio Verde/Salt River, Northwest Pinal County, Cave Creek/New River, Apache Junction/Gold Canyon, Gila Bend, Buckeye/Avondale, Central La Paz, New River Mesa, Northwest Valley, Sonoran Desert Natl Monument, Fountain Hills/East Mesa, Southeast Valley/Queen Creek, Aguila Valley, South Mountain/Ahwatukee, Kofa, North Phoenix/Glendale, Southeast Yuma County, Tonopah Desert, Central Phoenix, Lake Havasu and Fort Mohave