FORECAST SUMMARY:
FORECAST SUMMARY: Monday, July 12th, 2021 through Friday, July 16th, 2021
Ozone: 8-hour average Ozone concentrations are expected to be mostly Good throughout the week with a chance of Moderate concentrations in West Michgian along the Lake Michigan shoreline on Wednesday.
PM-2.5: 24-hour average fine Particulate concentrations will be mostly Good with low-Moderates possible from Canadian wildfire smoke plumes in the Upper Peninsula.
FORECAST DISCUSSION:
Upper-level temperatures will be in the low-teens for much of the week with some increasing into the mid-teens. Winds aloft shift from easterly at the beginning of the week to more west/southwesterly by mid-week. Clouds, precipitation chances, and easterly winds should keep air quality Good Monday into Tuesday.
The Low-pressure has a warm front associated with it that will result in warm air advection past mid-week as the boundary pulls north. This will also bring moisture into the region increasing surface dewpoint temperatures and humidity. Accompanied with the warmer temps, southwest winds are expected; however, clouds and precipitation move in the forecast Thursday into Friday as another Low-pressure area moves in. Clouds may clear long enough Wednesday to allow for a few Moderates ozone concentrations in western lakeshore areas; otherwise, levels will be generally Good. Fine particulate is expected to remain Good Wednesday. Clouds and precipitation should again keep ozone generally Good Thursday and Friday while fine particulate will likely be a mix of middle Good to low Moderate.
A weak cold front is expected Friday afternoon associated with the back end of the Low-pressure. This will make way for a High-pressure system to set up for the weekend. Canadian wildfires still present smoke plumes for the upper-Midwest region. The Upper Peninsula has a rather thick plume aloft on Monday which is expected to diminish in the coming days due to east-southeast winds for the first half of the week. These winds will also help to keep the plume out of the lower peninsula during the week, but northerly winds during the weekend may bring the plume back over the state.
EXTENDED FORECAST:
A high-pressure system sets up over the western Upper Peninsula region behind the cold front which should bring relatively clear skies and Good Ozone concentrations. We will update this forecast Friday to better detail possible pollution increases due to the wildfire smoke.