A Union Pacific Railroad mixed freight train derailed, caught fire, and caused the collapse of the heavy rail bridge over Tempe Town Lake. That bridge reportedly was the site of another derailment in June. The location is a low speed section. with an area light rail bridge next to the heavy rail bridge. Just on the north side of the bridge is a major highway loop, Loop 202, carrying people in and out of Phoenix. The smoke could be rising into one of the Phoenix Sky Harbor Airport landing flight paths, and they were be keeping an eye on the potential explosion of tanker cars. Reportedly, the FAA redirected flight traffic onto the north runways, to keep further low flying traffic out of the area. Thankfully, no lives have been lost so far in this derailment.

A stretch of Loop 202 was closed for several hours, but ADOT reported Loop 202 reopened in time for afternoon commuter traffic. A traffic camera image from 5 pm showed no sign of smoke left at the west end of the railroad bridge.