After a few hours of above zero temperatures, the mercury dipped to -4 by 6 a.m. today with a wind chill factor of minus 15, according to the National Weather Service.
The high today is expected to reach 11 but wind chills will not go above zero. A low of -2 is expected tonight.
Schools are back in session according to an email from Deerfield Public Schools District 109 Superintendent Michael Lubelfeld and a notice on the Deerfield High School website.
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