Dust Storm in Northwest Pinal County, Arizona

Trained spotter reported visibility down to 500 feet in Arizona City due to dense blowing dust from thunderstorm outflow winds. No accidents nor injuries were reported.

With the subtropical high pressure situated over the Four Corners, the steering flow across AZ was from the southeast. This southeasterly flow advected greater moisture content into the area with PWAT values surging to 1.5+ inches. The moisture combined with the daytime heating resulted in MLCAPE values in excess of 1000 J/KG. A strong to severe thunderstorm complex developed over southeastern portions of AZ by the late afternoon hours and then migrated northwestward toward south-central AZ during the evening hours with outflow winds generating areas of dense blowing dust as well as triggering additional thunderstorm activity over portions of the Phoenix metro area.