FORECAST SUMMARY: Wednesday, June 29th, 2022, through Friday, July 1st, 2022
OZONE: 8-hour average Ozone concentrations are expected to be mostly Moderate Wednesday and Thursday except for possible USG levels Thursday in West Michigan. Friday should have readings ranging from Good to Moderate.
PM-2.5: 24-hour average Fine Particulate will range from Good to low Moderate.
FORECAST DISCUSSION:
A weak front brought precipitation early Wednesday across parts of the state. This boundary sinks south into northern Indiana and Ohio before lifting back north as a warm front early Thursday. Precipitation ends and clouds dissipate as Wednesday progresses and as the front lifts back north on Thursday, we can expect warm temperatures and increased humidity to return. Precipitation chances do make its way back into the forecast late Thursday into Friday as a cold front travels from northwest to southeast through the state.
As for air quality, light winds with a northerly to westerly component should hamper ozone development Wednesday with readings ranging from Good to Moderate. On Thursday, warm south/southwesterly winds at both the surface and upper levels develop. This coupled with amble sunshine and dew points in the low 60s makes a good set up for ozone, especially in west Michigan. Because of this, we have an Action Day in place Thursday for the counties we feel have the highest threat for USG levels of ozone. While there is a small chance a monitor may reach USG in the southeast, the stronger southwest winds in that portion of the state should hamper ozone from increasing significantly; therefore, we will forecast Moderate for that portion of the state.
Clouds will be more prevalent Friday and chances for precipitation develop as a cold front sinks in from the northwest. Southern portions of the state that experience more sunshine due to the later frontal passage may reach middle to upper Moderate for ozone, otherwise, reading should be Good to low Moderate. Without a prolonged stagnation setup expected the next few days, PM2.5 during the period should range from middle Good to low Moderate.
EXTENDED FORECAST:
After a cold front passes Friday, extended forecast models show primarily dry conditions for the coming weekend. What is uncertain at this point is a system that may bring rain by the July 4th holiday. With the uncertainty in the forecast, we will do a Friday update to get a better handle on weather conditions, and in turn air quality conditions, for the weekend into the July 4th holiday.
Forecast updated by: Stephanie M. Hengesbach: Monday, June 29, 2022
Next Forecast update: Friday, July 1st, 2022