FORECAST SUMMARY: Monday, April 14, 2025, through Friday, April 18, 2025
Ozone: 8-hour ozone concentrations are expected to range mostly Good (Green AQI) with scattered low Moderates (Yellow AQI) possible Thursday.
PM-2.5: 24-hour daily average Fine Particulate concentrations will range between Good (Green AQI) to low Moderate (Yellow AQI).
FORECAST DISCUSSION:
A storm system north of Lake Superior will produce a variety of weather conditions early this week. Warmer temperatures can be expected Monday with a warm southerly flow ahead of the system, but as the low and associated cold front pass through, cold air moves in as winds change to a strong northwesterly flow. This flow produces a setup for lake effect snow accumulations across parts of the Upper Peninsula Monday into Tuesday, and the National Weather Service has Winter Storm Warnings and Winter Weather Advisories in place to highlight this threat. Accumulating snow is also possible in parts of northern lower, but any accumulations will be light. Further south, snowflakes may be seen, but snow accumulation is not expected. As the week progresses, high pressure slides in from the west Wednesday, and by Thursday temperatures rebound as southerly winds return. The next weather system moves in from the west late Thursday into Friday, bringing precipitation back into the forecast.
As for air quality, the period begins with a mix of Good to low Moderate fine particulate levels and Good ozone readings; an improvement to all Good is expected once the northwest winds kick in. Good air quality levels can be expected Tuesday into Wednesday, but as winds decrease and switch to the southwest past mid-week, both fine particulate and ozone may increase into the low Moderate range.
EXTENDED FORECAST:
The extended weather models show the Friday system departing Saturday with dry conditions anticipated later Saturday into Sunday. High temperatures on Saturday will range from the 40s north to the 50s south, increasing into the 50s north and 60s south on Sunday. Pollution levels during this period may reach the Moderate range.
Next Forecast update: Friday, April 18, 2025