Lake Michigan can make some crazy temperature changes. Saturday, the temp. at the Chicago Water Intake (Harrison-Dever Crib) reached at least 94.1°. The intake is 2.75 miles east of downtown, the Lake Michigan surface water temp. was 69°. It’s very unusual to get a temp. that warm. Midway Airport got to 97°. There was a brisk southwest wind, so the air wasn’t spending a lot of time crossing those 2.75 miles.
At 4 pm, the air temperature was 92.3°, the relative humidity was 49% and the wind was southwest at 15 mph with a peak gust of 38 mph. One hour later, at 5 pm, the temperature was 72.6°, the relative humidity was 95% and the wind was northeast at 22 mph with a peak gust of 32 mph.
That’s a one-hour temp. drop of nearly 20 degrees, the relative humidity goes up 46% and look at the air convergence going on where that southwest wind met the northeast wind.
Read more at WOODTV.com.