Aug 13, 2017
Scattered to numerous thunderstorms developed across the greater Phoenix area during the morning hours on August 13th and they produced locally heavy rainfall which led to a number of flash flooding episodes that affected communities such as Surprise, Glendale and Tempe. Intense rainfall with peak rain rates over one inch per hour was more than sufficient to produce flash flooding in Phoenix, especially given the urban nature of the surface which is largely ground covered by impermeable concrete
Source: NOAA National Weather Service Storm Events Database (event 713369). Narrative written by NWS staff at the time of the event.
This event is one of many recorded floods in Maricopa County. See the full FEMA flood zone map, NFIP claim totals, and disaster history for the area.