Arizona Air Quality Information

First Significant Dust Storm Of Monsoon 2020 Hits Phoenix


The Valley of the Sun has been living up to its name lately with sweltering hot temperatures and very dry conditions.

So far this monsoon, Phoenix Sky Harbor has only seen measurable rain one day, which produced a meager 0.10 inches. Looking at rainfall data from June 15th to August 16th, this is now the driest monsoon on record.

With these dry conditions, it is no surprise that drought conditions are also getting worse. Back on June 15th, the Valley was considered drought-free when looking at short-term drought. The latest drought numbers now show severe drought covers the Valley and stretches down through Pinal County.

What does all of this mean? The dust storm potential is high.

[Read more: Learn about PM-10 an how to protect yourself]

This high risk was proven yesterday, as strong to severe thunderstorms developed to the north and southeast of the Valley. As these thunderstorms collapsed, they sent out strong outflows winds, which produced two dust storms. One dust storm moved in from the north, with another moving in from the south before converging over the center of the Valley.

The dust storms caused seven PM-10 (dust) monitors in Maricopa County to exceeded the federal health standard. The highest monitor in the Valley was West Chandler, coming in at 155 AQI, which is in the Unhealthy AQI category. This dust storm also ended a 227-day streak of no PM-10 exceedances in the Valley, which is now the 5th longest streak on record.

With not much rain falling around the Valley or in Pinal County yesterday, the potential still exists for dust storms as more thunderstorms are in the forecast today. As a result, a PM-10 High Pollution Advisory has been issued for Maricopa County today (Aug 17th).

[View: Phoenix Hourly Air Quality Forecast]