The state Department of Transportation says the highway between Interstate 17 and Lake Pleasant Parkway is closed. The route is popular with drivers heading to or returning from Las Vegas.
Officials say motorists can take Loop 303 as an alternative east-west route.
A dust storm and monsoon blew through the Phoenix metropolitan area late Tuesday, flooding some streets in Anthem and along I-17.
The Arizona Republic reports firefighters rescued several people who were trapped in their vehicles Tuesday night on a highway west of I-17. No injuries were reported.