The National Weather Service has issued a wind chill advisory for McHenry County.
The advisory is in effect midnight Thursday through 10 a.m. Friday. Freezing wind chills are expected, with temperatures ranging from 20 degrees below zero to 30 below zero. Frostbite could occur in just a half hour if skin is exposed, according to the weather service.
The service advises people to wear hats and gloves to avoid hypothermia and frostbite.
Temperatures aren’t expected to rise above freezing through Monday, according to the service.
Snow is predicted for the weekend, with a 30 percent chance of light snow Saturday night, and a 40 percent chance of light snow during the day Sunday, according to the service.