UPDATE — Wednesday, October 21, 10:40 PM CT: The National Weather Service in Flagstaff says the severe storm is now 14 miles northeast of Sun Valley and 22 miles northeast of Holbrook, moving northeast at 40 mph. The storm is still packing golf ball-size hail and 60 mph wind gusts, with a considerable damage threat. Sun Valley, Petrified Forest National Park and the surrounding wilderness area are in its path, along with I-40 between mile markers 298 and 316 and State Route 77 between mile markers 405 and 408. The warning remains in effect until 9:00 PM MST.

Holbrook, AZ — A severe thunderstorm warning is in effect for Navajo County and Apache County in northern Arizona through 8:30 PM MST.

What is happening: The National Weather Service in Flagstaff reports a severe thunderstorm sitting right over Holbrook and moving northeast at 40 miles per hour. It is throwing 60 mph wind gusts and half-dollar-size hail. Communities in its path include Holbrook, Sun Valley, Lisitzky Subdivision, Rosedale Heights, Clearview Heights, the Holbrook Municipal Airport, and the Petrified Forest National Wilderness Area. Drivers should expect rough conditions on Interstate 40 between mile markers 278 and 304, Business I-40, State Route 377, State Route 77, and Highway 180, as well as at Hunt Park.

Local impacts: Hail damage to vehicles is expected, along with wind damage to roofs, siding, and trees. The weather service adds that tornadoes can develop quickly from severe thunderstorms.

What to do:

- Get inside a well-built structure and away from windows right now.

- If you are on I-40, exit and shelter in a sturdy building.

- Stay inside until the warning ends at 8:30 PM MST.

Source: National Weather Service, Flagstaff, Arizona. Issued October 21, 2026.