Fog found its way back to Chicago after a bit of sun and a double derecho that on Monday dumped eight tornadoes across the region.
The familiar shroud over downtown — a parting gift from the polar vortex — returned Wednesday as northerly winds and low cloud cover kept temperatures in the low 60s and high 50s, making it more like autumn than July 2.
“There’s an awful lot of moisture in the air that extends from central Illinois all the way to southern Wisconsin. The mist is restricting visibility, but as the night wears on and the sun comes out in the morning, it will improve,” said Charles Mott, meteorologist with the National Weather Service in Romeoville, where visibility was 5 to 6 miles Wednesday evening.Visibility was much more limited in Chicago.
The wind was coming across colder waters farther north on Lake Michigan, helping to generate the fog, Mott said, “and the water and air temperatures are close. Actually, the air temperature is a little colder on land than the water temperature.” It was 57 degrees at O’Hare about 7:30 p.m. Wednesday. Lake water temperatures near the city were in the mid to upper 60s.