Overview
- A second extreme haboob rolled into the Valley early Thursday, Aug. 6, following a Category 5 dust event earlier in the week, with both storms ranked Category 5 on ASU’s PHX Dust Storm Scale.
- Air monitors recorded dangerous particulate spikes, including a west Chandler sensor that peaked near 5,841 µg/m³, and visibility fell to about 0.5–1 mile during peak gusts.
- The Arizona Department of Environmental Quality issued a high pollution advisory and urged people with asthma, COPD, young children and the elderly to avoid outdoor exposure.
- Forecasters say the storms were driven by outflow winds from decaying southern Arizona thunderstorms, little wetting rain followed to clear the dust, and extreme heat warnings remain in effect through the weekend with rain chances rising early next week.
- Researchers note the back-to-back Category 5 events are rare—only the fifth and sixth in roughly 16 years—and say regional drought and climate-driven shifts in storm patterns can raise the odds of intense dust storms in future monsoons.