FORECAST SUMMARY: Friday July 21st, 2023 through Saturday July 22nd, 2023
PM-2.5: PM-2.5 concentrations are expected to be in the Good to Moderate range.
OZONE: Ozone concentrations are expected to be in the Good to Moderate range.
FORECAST DISCUSSION:
How we end the work week is exactly how we start off the weekend with partly sunny skies and surface temperatures hanging around the upper-70s to low-80s. The airmass that was brought to us with the passing cold front yesterday, Thursday, hangs around through the weekend, with no major change in airmass until Monday. Winds will remain predominantly NNE today before slowly shifting to WSW tomorrow afternoon. As we approach Sunday, winds complete their shift and becoming more southwesterly flow all day Sunday and through Monday.
Due to the warm temperatures, ample sunlight and favorable winds for Ozone development, this forecast will be updated tomorrow, Saturday, to get a better look at conditions for Sunday. Upper-level temperatures appear to remain in the low-teens Celsius throughout the weekend, but this year has shown us Ozone developing in atypical scenarios. Traditionally, upper-level temperatures in the mid-to-upper teens Celsius and a southwest wind would be indicative of Ozone development, but we have seen cooler temperatures be conducive for Ozone this year. As of now, most models are not showing too much Ozone developing ashore in West Michigan, or at least over the USG threshold, but to play it safe, I will take a better look tomorrow with updated models and forecasts. For PM-2.5, we continue to see low-mid Moderate in some areas, and Good concentrations in other areas. Wildfire smoke does not look to be an issue for the foreseeable future.
EXTENDED FORECAST:
A front comes through most of the state on Monday but looks to stall over the southern portion of the lower peninsula. Winds look to remain SW so this will be looked at throughout the weekend.
Next Forecast update: Saturday July 22nd, 2023. Forecast updated by Alec Knowacki.