military discovered that our soldiers were suffering frostbite in temperatures that didn’t appear to be cold enough to produce it. Skilling:During the Korean conflict, the U.S. I wanted to take a video so I could remember this, and my phone just shut off. It was remarkable to see the steam coming off Lake Michigan - it was otherworldly, like a scene out of a sci-fi film. I now understand why frostbite can occur within minutes. You could feel the cold the second you stepped outside. That morning, I drove to the lakefront and did what I probably shouldn’t have done: I got out of the car. I hadn’t seen that before due to cold weather. The city basically shut down to keep everyone as safe as possible. It’s definitely the coldest weather I’ve ever witnessed. The temperatures dropped to 23 below zero the morning of January 30, and wind chills ranged from 45 to 56 below. Scott:I’ll never forget the polar vortex of 2019. That blizzard introduced a level of wind along the lakeshore that was extraordinary. That means they come off the lake friction-free. I talked to one woman who was stuck in her car and said, “Look, I knew the storm was coming, but I hadn’t expected that a CTA bus would jackknife and block traffic.” Oh my word, we had 70-mile-an-hour winds. And he put this line: “What part of ‘blizzard warning’ didn’t these folks understand?” Of course, there were extenuating circumstances. Louis Uccellini, who is a friend of mine and became head of the National Weather Service, emailed me a picture of all these cars stuck in snowdrifts on Lake Shore Drive. Skilling:I remember there was a blizzard advisory out two days ahead of the Groundhog Day blizzard of 2011. “I now understand why frostbite can occur within minutes” There’s some data looking at the top 10, and Chicago isn’t even on the list. But we’re not the windiest city in terms of wind speed. And Chicago has these tall buildings, so when we get cold wind off Lake Michigan - which controls almost a third of our weather - the buildings and streets act almost like canyons that help funnel it and make it go even faster. Moving down a frictionless lake, it gains all of this momentum. Scott:Wind is driven by pressure differences in the atmosphere and starts with the sun, which heats the atmosphere. In the fall, that keeps the climate milder near the lakefront. So once a body of water like Lake Michigan cools, it stays cool and takes a while to warm up. Water has an interesting property: It hangs on to energy for a long period of time. If you’ve got Tater Tots in the oven, you can pull them out and grab the aluminum and you won’t burn your hands, because it dissipates heat quickly. Miller:Materials have something called specific heat - how they retain heat and how they lose heat. Then, on top of that, we have this little thing called Lake Michigan sitting next to us. We have the retreating cold of winter fighting with the building warmth of spring and summer. We’re in a midlatitude atmospheric clash zone where weather tends to change rather precipitously and rapidly. If you want a variety of weather to forecast, it does make the job awfully interesting. John Coleman used to call it Broadway for weathermen, and it really is true. Skilling:We’re in a very volatile weather regime around Chicago.
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