Maricopa County Sheriff's deputies say 68-year-old Susan Stolki was heading east on Tepee Drive around 7 a.m. when she struck a mailbox and a tree.
Deputies say the vehicle came to a stop, rolled onto its top.
Stolki was the car's sole occupant.
Authorities say speed does not appear to be a factor.
The intersection was closed for several hours before opening back up at noon.