FORECAST SUMMARY: Thursday, June 1, 2023, through Friday, June 2, 2023

Ozone: 8-hour average Ozone concentrations will range between Moderate and USG.

PM-2.5: 24-hour average Fine Particulate should remain mostly Moderate.

...AIR QUALITY ACTION DAY ADVISORY FOR THURSDAY, JUNE 1ST AND FRIDAY, JUNE 2nd...

THE ACTION DAY ADVISORY IS IN EFFECT FOR THE FOLLOWING MICHIGAN COUNTIES...

IN WEST and central MICHIGAN:

ALLEGAN... BARRY... BENZIE… berrien… BRANCH... CALHOUN... CASS… CLINTON... EATON... GRAND TRAVERSE... HILLSDALE... INGHAM... IONIA... JACKSON... KALAMAZOO... KENT... LEELANAU… MANISTEE… MUSKEGON... Oceana… ottawa… MASON… ST JOSEPH AND van buren COUNTIES

IN Southeast MICHIGAN:

GENESEE... LAPEER... LENAWEE... LIVINGSTON… MACOMB… MONROE… OAKLAND… ST. CLAIR… SHIAWASSEE... WASHTENAW AND WAYNE COUNTIES

FORECAST DISCUSSION:

The current forecast trend continues as we move towards the end of the workweek. High pressure remains in place providing summer-like heat. Higher moisture levels in the western portion of the state may allow for scattered shower/storm development again Thursday afternoon, most generally in the western portion of the state near the afternoon/evening lake breeze. A lighter southeasterly flow Thursday switches to more of an easterly direction Friday. A light wind flow persists at upper levels and temperatures remain at readings conducive for ozone development.

Ozone was not worse than upper Moderate Wednesday, but many locations reported a few hours in the USG range with 8-hour averages not far from the USG threshold. Without a significant weather change to improve ozone conditions, we are continuing the Clean Air Action Day into Friday. The Action Day covers the southern half of lower Michigan, along with the west lakeshore counties further north towards Traverse City.

Fine particulate levels during the week have been mostly low to middle Moderate, and we anticipate readings remaining in that range the rest of the week.

Weather maps are hinting at a weak boundary Saturday. This system will not bring much, if any, precipitation, however, surface temperatures should be closer to normal and cooler upper-level temperatures move towards the region. This will hopefully aid in decreasing ozone concentrations. This forecast will be updated Friday to better detail expected weekend pollution levels.

EXTENDED FORECAST:

Air Quality should be generally Moderate, with possible USG this coming weekend into early next week.

Next Forecast update: Friday, June 2, 2023

Forecast updated by: Stephanie M Hengesbach. Thursday, June 01, 2023