Heavy Rain in Maricopa County, Arizona

Strong thunderstorms with extremely heavy rain led to mutiple collisions on Interstate 10 in downtown Phoenix during the afternoon hours on August 28. A total of 69 vehicles were involved in a series of crashes; one collision alone involved 35 vehicles and spanned over 2 miles from 16th street to 7th street. Trained spotters reported visibilities below one quarter mile in heavy rain in downtown Phoenix, and it was low visibility in heavy rain that led to the collisions. Seven people were taken to area hospitals and two were in serious condition. Fire officials medically evaluated at least 40 people.

Strong thunderstorms across south-central Arizona produced damaging winds, hail and extremely heavy rainfall. Heavy rain with near zero visibility led to a massive traffic pileup in downtown Phoenix.