FORECAST SUMMARY: Wednesday, May 31, 2023, through Thursday, june 1, 2023
Ozone: 8-hour average Ozone concentrations will range between Moderate and USG.
PM-2.5: 24-hour average Fine Particulate should remain upper Good to low Moderate.
...AIR QUALITY ACTION DAY ADVISORY FOR WEDNESDAY MAY 31st AND THURSDAY JUNE 1ST...
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:
Summer-like heat continues over the state thanks to high pressure remaining in control. Increased moisture Wednesday and Thursday will allow for some cloud development during the afternoon along with a few pop-up showers or storms mostly in west Michigan along the lake breeze. Winds Friday look to switch to more of an easterly component; however, even with a change in wind direction the trend of warm temperatures and dry conditions continues.
Ozone in the USG range was seen Tuesday at some western lakeshore and a few central monitors. While 8-hour averages in much of the state stayed Moderate, averages were not far from the USG threshold and a few hours with concentrations in the USG range were seen. Some afternoon clouds and isolated precipitation may hamper ozone development in a few locations Wednesday and Thursday; however, much of the state will remain dry and mostly sunny. Considering we are under the same airmass for several days now and we’ve already seen increased pollution in many locations, we have decided to continue the Clean Air Action Day into Thursday. Also, since inland monitors have seen increases recently, we are extending the Action Day Thursday to encompass the southcentral portion of the state, including the cities of Lansing, Jackson, and Hillsdale.
Air Quality levels will be monitored during the day and if any forecast area not in the current Action Day look to exceed the USG threshold, the forecast will be updated from Moderate to USG triggering EnviroFlash notifications.
Fine particulate levels during the week have been ranging between upper Good and low Moderate. We anticipate increases in fine particulate as well, however, levels should not reach higher than low to middle Moderate.
The same airmass remains over the region until the coming weekend. Since the threat for increased ozone continues through the week, this air quality forecast will be updated daily until the threat ceases.
EXTENDED FORECAST:
Air Quality should be generally Moderate to USG through the coming weekend.
Next Forecast update: Thursday, June 1, 2023
Forecast updated by: Stephanie M Hengesbach. Wednesday, May 31, 2023