Smoke From Wildfires Up North Seen in Northern Illinois and Southern Wisconsin

Your eyes were not playing tricks on you this afternoon.  It definitely looked hazy and smoky outside.  Haze and smoke could been seen from Iowa, Illinois, Wisconsin and Minnesota much of Thursday morning and afternoon.


The reason: smoke from large wildfires burning in central and northern Canada.  A cold front came through late last night.  Cooler and more dense air followed the front, providing a sinking motion in the atmosphere.  As the jet stream turned more northwest this morning, the smoke from the wildfires were caught within the winds of the jet stream and transported southeast, into the Midwest.  While we've seen smoke from wildfires as far north as Canada and the northwest before, today was a little more rare.  That's because the smoke was pulled down towards the surface of the earth, reducing visibility for some time in many locations.

Sinking air from the top of the atmosphere down to the surface brought the smoke downward.  Visibility in some locations has improved from earlier, and this should be the overall trend we see through the night.  However, if the smoke lingers a little longer into the night it could get 'trapped' near the surface keeping the hazy look around through Friday morning.


The lingering smoke could make for a colorful sunset Thursday evening.  Smoke particles act as filters in the atmosphere for sunlight, scattering the shorter wavelengths of light and leaving the longer ones behind - like orange and red.  The lower the sun is on the horizon, the longer the light has to pass through the atmosphere making the colors extra bright.