Even though Chicago's winters have gotten milder overall in the last 50 years, extreme temperatures like we had between Christmas and January 7th still kill people:
Unlike other more dramatic types of weather, such as hurricanes, floods or tornadoes, the threat of extreme cold or heat tends to be overlooked, said Laurence Kalkstein, a University of Miami public health sciences professor who studies the effects of climate on human health.
“People don’t think of it as much of a threat mainly because there are no physical signs that a calamity has taken place,” Kalkstein said. “Clearly, it is underestimated as a danger.”
Cold weather has claimed the lives of hundreds of Illinois residents during the past decade. The Illinois Department of Public Health reports 593 people died from exposure to excessive natural cold or hypothermia between 2008 and 2016. The highest yearly total was 110 in 2014, when the polar vortex hit in January.
[T]he overall mortality rate in the winter is about 10 to 12 percent higher than in the summer because of all the indirect ways cold, snow and ice contribute to deaths, including car crashes, falls and heart attacks. There are also a higher number of infectious-disease deaths because influenza thrives when people remain inside because of cold weather....
We had March-like temperatures this weekend, but this morning, it's January again. At least we've got noticeably more daylight, and only 31 more days of meteorological winter.