Projected overnight lows (NWS)If you have any plants or vegetation prepare to protect them. Tonight the NWS will be issuing a freeze warning for the northern Illinois region. Overnight lows are to dip below the freezing mark. Widespread frost is highly likely. Highs Sunday probably will not make it out of the 40s.
Artic Oscillation indicates cold airmass to linger for the next several days
6-10 day temp. anomaly map (CPC)
