07/12/2019 Forecast Update


Friday, July 12th, 2019 through Sunday, July 14th, 2019

Ozone:  8-Hour average Ozone concentrations will be a mixture of Good and Moderate through Sunday.

PM-2.5:  24-hour average Fine Particulate concentrations will be mostly Good with some Low Moderate.


We will enter into the weekend with Air Quality on the Good side.  That trend will last through Saturday as a cold front drops down through the state.  There may be some convective activity associated with the frontal passage but the indicators are that this is more unlikely than likely.  Winds will shift to the northwest during the afternoon and provide a good cleanout of the atmosphere.

Post-frontal winds, during Sunday, will be light and biased to the northeast shifting to southeast.  The areas most at risk for any ozone creep will be west of the Detroit area, such as Flint.  But, coming off a clean Saturday, it is unlikely that the creep would be any worse than Moderate.

The upcoming work week may be challenging for Air Quality forecasting.  Indications are that we will be entering a prolonged period of hot, humid weather ripe for ozone production.  The wild card is Tropical Storm Barry, currently in the Gulf of Mexico, and not knowing how it will influence our upcoming weather.

Considering the uncertainty, the latest model runs will be reviewed on Sunday and this forecast will be updated.


Air Quality is currently expected to remain mixed Good to Moderate going into the next work week.

Forecast updated by Jim Haywood: Friday, July 12th, 2019
Next forecast update: Sunday, July 14th, 2019