The mid-spring heat has made its return to the valley, with high temperatures reaching the 100°F mark yesterday at Sky Harbor for the first time this year. Similar highs are forecasted for today, but fortunately, active weather and lower temperatures will return starting tomorrow and lasting through the end of the week. Let's discuss what this means regarding air quality.

Ozone has now become the pollutant to watch as we move into the warmer months. More daily sunlight allows for a higher yield of ozone to form at the surface when conditions are stagnant in more populated areas. Hours with the highest ozone levels tend to occur around 11:00 a.m.-6:00 p.m. For this week, concentrations will be highest today as winds become relatively light and shift in the afternoon due to the incoming disturbance.

By tomorrow, southwest winds will increase in the afternoon, with similar trends expected through Friday. Ozone is forecast to drop well within the Moderate AQI after today and through the rest of the work week. PM₁₀ (dust) may become more elevated during windier periods, but no blowing dust events are currently expected.

Make sure to hydrate and have a great start to your week!

- B. Droppleman
ADEQ Meteorologist