FORECAST SUMMARY: Tuesday, July 19th, 2022, through Thursday, July 21st, 2022
OZONE: 8-hour average Ozone concentrations are expected range from Moderate to USG Tuesday with Good to Moderate readings the rest of the forecast period.
PM-2.5: 24-hour average Fine Particulate will primarily range from Good to middle Moderate.
FORECAST DISCUSSION:
A frontal boundary positioned over northern Michigan brings clouds and chances for precipitation. Further south, high pressure dominates with plenty of sunshine and warm temperatures both at the surface and upper levels. This coupled with southwesterly winds and dew points in the low-middle 60s makes increased ozone a good possibility. Because of this, we have an Action Day in place for both west and southeastern portions of the state.
As Wednesday progresses, the boundary in the north tracks north as an associated cold front approaches from the west. This cold front brings increased clouds and chances for precipitation. Surface and upper-level temperatures will still be warm, but increased dew points close to the 70s, and more clouds, should hamper increases in ozone. There is a small chance a monitor or two in the far southwest may reach low-end USG, otherwise reading should not reach higher than Moderate.
There will not be much of a temperatures drop behind the front Thursday, but stronger northwesterly winds develop. Sunny skies will prevail, but we expect the northwesterly flow at the surface and upper levels to hamper ozone increases. Levels Thursday should range from Good to Moderate. Weak high pressure moves in Friday with winds turning back to the southwest. We feel conditions Friday warrant another look; therefore, this forecast will be updated Thursday to detail expected air quality conditions for Friday.
As for fine particulate, readings have been running between middle Good and low Moderate and we expect levels to continue in that range through mid-week. As the upper-level flow turns northwesterly Thursday smoke forecast maps show a smoke plume sinking south from Canada. Maps are keeping this thicker plume to our west over Minnesota, Wisconsin, and parts of western Illinois and Indiana. We felt this should be noted since if the plume pulls further east, we may see increased fine particulate due to smoke closer to the ground. Even with the increase, however, levels during the week should not reach higher than middle Moderate. At this time, we feel the plume will not do much to change expected ozone concentrations. If our thoughts on this changes, we will send out an updated forecast.
EXTENDED FORECAST:
Weekend forecast maps show a boundary positioned around southern Michigan with disturbances bringing on and off showers/storms for the weekend. If this pans out, air quality through early next week should stay between Good and Moderate.
Forecast updated by: Stephanie Hengesbach: Tuesday, July 19th, 2022
Next Forecast update: Thursday, July 21st, 2022