In this secluded paradise, mail still arrives by mule, turquoise cascades tumble into travertine pools, and time flows at the pace of the river.

The NWS warning was in effect for regions of the Grand Canyon below 4,000 feet elevation. Temperatures were forecast to potentially reach 110 degrees at Phantom Ranch and 102 at Havasupai Gardens.

Wildfires can burn and spread differently depending on what vegetation they burn. The two fires in northern Arizona have varied landscapes. Ponderosa pine trees grow near the North Rim of the Grand Canyon and can live for hundreds of years.

The resulting Nankoweap landslide would have dumped enormous limestone boulders into the river corridor, creating a temporary dam and a lake whose surface may have reached 940 meters elevation before water overtopped and eroded the blockage, likely within 1,000 years.

A water treatment facility at the North Rim had been compromised by the fire, causing chlorine gas to fall towards the bottom of the canyon.

Arizona senators are demanding answers from the Department of the Interior about allowing an ongoing wildfire at Grand Canyon National Park to burn for several days before trying to stop it.