FORECAST SUMMARY: Friday, September 20, 2024, through Monday, September 23, 2024
OZONE:
Ozone concentrations are expected to range between Good (Green AQI) and Moderate (Yellow AQI).
PM-2.5:
PM-2.5 concentrations will average between Good and Moderate.
FORECAST DISCUSSION:
Two boundaries, one passing through Friday and the other Sunday, bring some much-needed precipitation into the forecast. There is not much of a temperature decrease behind the Friday front, and dry conditions return for Saturday; however, conditions will feel a bit muggier than earlier in the week. On Sunday, the second boundary passing through brings in more widespread precipitation chances. Temperatures through the weekend continue trending above normal.
Since Monday levels of ozone and fine particulate have generally ranged from Good to Moderate, aside from yesterday when three western monitors climbed just over the Unhealthy for Sensitive Groups (USG) range for ozone. On Friday, clouds associated with the frontal boundary should hamper ozone development, keeping readings ranging from Good to Moderate through the state. Dry, sunny conditions on Saturday will likely allow for ozone increases into the Moderate range over much of the state, but more cloud cover and precipitation by Sunday afternoon should bring readings into the Good to low-Moderate range. Without a significant airmass change expected through the weekend, daily averages of fine particulate will continue to range from Good to low Moderate.
EXTENDED FORECAST:
Extended forecast models show rain chances lingering into early next week, with high temperatures becoming closer to normal for this time of year. Air quality should range generally Good early next week.
Next Forecast Update: Monday, September 23th, 2024