Thunderstorm Wind in Pinal County, Arizona

Downed powerlines reported on SR-287, between Main St and Valley Farms Rd in Florence, leading to a closure of the highway. No injuries were reported.

Thunderstorm activity developed across much of eastern AZ, along the higher terrain features, during the early afternoon hours. Outflow boundaries emanating from the activity over the higher terrain areas sparked a complex of robust thunderstorms over Pinal County. A northwestward moving outflow boundary that developed from the Pinal County storms produced wind gusts in excess of 50 mph as well as areas of dense blowing dust across the Phoenix East Valley. Additional thunderstorm activity then developed over central Phoenix during the late afternoon, likely instigated by a convergence zone that set up right over the area with little convective inhibition in place and thus it did not take much of a triggering mechanism to get convective initiation. With MLCAPE values of 1000-1500 J/KG along with DCAPE of around 1500 J/KG, conditions were favorable for the generation of strong to severe downburst winds.