Authorities were called after two people went missing from a rafting trip following the flash floods on Thursday Colorado River.
Rebecca Copeland of Ann Arbor, Michigan, was named as the deceased. Another person was found injured. Five people were airlifted in the early hours of Friday, of which one is in critical condition.
Arizona Governor Doug Ducey also declared a state of emergency for Coconino County on Friday, freeing up the state’s $200,000 to help clean up.
Friday’s flooding appears to have been intensified by a lack of vegetation on a nearby mountain following the 2019 wildfires.
The western states have been scorching in record-breaking heat in recent weeks, with Flagstaff hitting 94F (34.4C) on June 15, a record breaking since 1974.
Sudden floods are common in desert areas as the land cannot absorb heavy rainfall due to dry ripeness in summer. The water can then flow through the valleys creating extremely dangerous conditions.
Elsewhere in the US, a severe tornado hit Columbia, South Carolina, on Friday afternoon that temporarily flooded some roads, with officials warning drivers to exercise caution in low-lying areas.
In Detroit, the I-94 freeway closed for the second time in less than a month on Friday due to flooding after heavy rain swept across the city.
In late June a typhoon closed a section of the road for a week. In response to the heavy rain event, President Joe Biden approved a disaster declaration for Michigan. The state was also hit by a series of tornadoes.
Meanwhile, on Friday in Missouri, Madison County flash floods had to rescue two people who were trapped on top of their vehicle by rapidly rising water.
This weekend, extreme heat warnings have been issued for severe thunderstorms across large parts of Montana and Idaho.
In the Northeast, flood warnings and flood watches cover large parts of Ohio and western New York. Up to three inches of rain has been predicted for a short period of time around Buffalo, prompting a warning from the National Weather Service.
Much of the rest of New York state, New Jersey, Pennsylvania and Washington, D.C. are prepared for the potential for strong thunderstorms on Saturday.
Parts of southeastern Kansas and northern Oklahoma have been told to prepare for potential flooding and a flood warning has been issued for areas of Wilson County, Kansas.