Pneumonia front sends temps 21-degrees lower in 2 hours Monday PM; ends warmest spell here in almost 3 weeks.

http://chicagoweathercenter.com/blog/pneumonia-front-sends-temps-21-degrees-lower-in-2-hours-monday-pm-ends-warmest-spell-here-in-almost-3-weeks

Chicagoans head out into a very different air mass Tuesday than the one responsible for Monday’s July-level 83-degree high–a reading 14-degrees above normal and the warmest daytime temperature to occur here in 19 days–nearly 3 weeks!  The passage of Monday’s “pneumonia front” at 5:48 pm set in motion a 21-degree temp plunge in only 2 hours time that followed. The dramatic cool-down which brought 7-consecutive days of above normal temps–including Saturday and Sunday highs of 79 and 78—to an unceremonious end.