Potential bomb cyclone to hit Chicago area Friday night

Another strong bout of weather will hit the Chicago area tonight, meteorologists said. 

The storm brought heavy snow to the area this morning. Jake Petr, a meteorologist with the National Weather Service in Romeoville, said some areas recorded upwards of 2 inches of snowfall per hour. That precipitation has since transitioned to rain in most areas as temperatures warmed. 

Weather should remain relatively calm through the afternoon and evening, Petr said, though fog is possible in the early evening. Petr urged residents to use this lull to regroup, snow shoveling if needed, as late evening will bring the resurgence of nasty weather. 

“We’re not expecting the accumulating snow to start back up until late this evening, say after 9, 10 p.m., and then through the overnight hours,” Petr said. “With that, we’ll have some pretty strong winds potentially as high as 40 to 50 miles per hour. We did see a little bit of that briefly this morning.”

Northwest suburbs will see the worst effects of the storm, Accuweather meteorologist Tom Kines said, as they continued to experience snowfall when Chicago’s precipitation turned to rain.

Some outlets have referred to the incoming storm as a bomb cyclone, a storm where the pressure drops and the storm intensifies very rapidly, but meteorologists say it is too early to say for certain. 

To classify the storm as a bomb cyclone, Petr said, the barometric pressure has to drop by 1 millibar per hour for at least 24 hours. These storms tend to occur a couple of times a year in the United States, Kines said. 

Kines said today’s weather “certainly could” intensify into a bomb cyclone, as the conditions are there. Due to the criteria required to classify it as such, though, it’s not possible to know for sure until tomorrow. 

Regardless of classification, travelers are encouraged to stay off the roads and indoors, especially later tonight. After 8 p.m. or so, roads will see significant snow blowing or drifting and slippery road conditions, with winds up to 50 mph. 

“Temperatures tomorrow are going to be in the teens in the afternoon. It’s gonna feel like it’s zero or below out there. So you’ve got to protect yourself from hypothermia and frostbite. Keep your body covered up and your hands and face and head and all that stuff. It’s not the best of weather to be outside in, or travel for that matter,” Kines said.  

Although snowfall should let up a bit after Saturday, cold, arctic air will quickly follow. Petr said wind chill on Sunday and Monday night are predicted to drop below negative 20 degrees. Fines urged caution when going outside in temperatures like these. 

“The cold air that follows the storm means business. That’s arctic cold,” Fines said.