FORECAST SUMMARY: Friday, July 1st through Tuesday, July 5th, 2022

OZONE: 8-hour average Ozone concentrations are expected to generally range from Good to Moderate through the holiday weekend; isolated USG is possible Sunday.

PM-2.5: 24-hour average Fine Particulate will primarily range from upper Good to middle Moderate, however, expect elevated hourly readings of USG or possibly higher during the late evening/early overnight hours in locations with fireworks displays.

FORECAST DISCUSSION:

A frontal boundary Friday continues traveling southeast through the state with chances for precipitation across the southeast as it moves through. Conditions dry out Saturday and Sunday as high pressure dominates the region. Another boundary moves in on July 4th bringing possible precipitation later in the day.

As for air quality, winds switching to the northwest after the fontal passage Friday will help keep ozone generally Good, however, the later frontal passage in the southeast may allow for Moderate ozone there. High pressure to our west Saturday produces north/northwesterly winds. This flow will help keep pollution levels from increasing. A few locations may experience Moderate ozone, but that should not be widespread. By Sunday, high pressure settles more overhead and light winds become southerly later in the day. Seasonable temperatures will be in place, but upper-level temperatures do not increase significantly. There is a chance an isolated monitor or two could reach low-end USG, but we expect most locations to be Moderate. By July 4th, a frontal boundary is sinking in from the northwest. Increasing clouds and chances for precipitation later in the day should keep ozone from reaching higher than Moderate.

Now for fine particulate, with it being the July 4th weekend we do expect the usual spikes in fine particulate with hourly readings well into the USG range during the late evening/early overnight hours in locations with fireworks displays. The days for the increases will vary depending on when areas have fireworks scheduled. Without a prolonged period of stagnation forecast through Monday, high hourlies should improve bringing daily averages of fine particulate closer to the Moderate range.

EXTENDED FORECAST:

Extended forecast models show a front passing by late Monday/early Tuesday. This should keep pollution levels from increasing higher than Good to low-Moderate as we move towards mid-week.

Forecast updated by: Stephanie M. Hengesbach: Friday, July 1, 2022
Next Forecast update: Tuesday, July 5, 2022