Crews in Chicago have begun setting train tracks on fire in order to keep public transit moving amid historically frigid temperatures throughout the Windy City.
The Chicago Tribune explains that wintry weather can cause snow and ice to clog the switches that control which rails Metra trains run on, thus grinding travel to a halt.
To prevent this from happening, gas-fed heaters that run adjacent to the rails are used to generate warmth in areas where switches are supposed to make contact by creating small, controlled fires that melt icy buildup.
Although the system is used in normal winter weather, not just in the extreme cold, videos of the eye-catching spectacle have been shared widely on social media by multiple local news outlets in the Midwest lamenting Wednesday's cold weather.
"IT’S REEAAALLY COLD! It’s so cold, train tracks are being set on fire to prevent freezing in Chicago," wrote Wisconsin's WISN 12 News on Facebook, alongside areal footage of the track fires, which has since been viewed over 600,000 times.
The U.S. Midwest braced for a record-breaking freeze this week as it was hit by "one of the coldest arctic air mass intrusions in recent memory," according to the National Weather Service.
Wind chills plunged parts of Illinois and Indiana into the negative 50s by Wednesday morning and brought parts of Minnesota, North Dakota and Iowa as low as 60 degrees below zero. A wind chill of just minus 25 can freeze skin within 15 minutes, according to the National Weather Service.
Chicago Mayor Rahm Emanuel issued a stark warning on Tuesday ahead of the historic cold snap.
"These are actually a public health risk and you need to treat it appropriately," Emanuel said. “They are life-threatening conditions and temperatures.”
At least five people have died so far as a result of the cold weather and icy conditions.