The National Weather Service has issued dense fog and flood advisories for McHenry County and much of Illinois.

Up to an inch of rain has fallen over portions of the state and, combined with rapidly melting snow, is causing rises of area streams and rivers. In some cases, water accumulating on fields is spilling onto roadways, according to the National Weather Service.

A thick fog is expected to cause low visibility through the evening hours. A dense fog advisory means visibility will often be less than a quarter mile, approaching zero in some areas.

The National Weather Service is urging motorists to take caution when traveling and to leave extra space between them and the vehicle ahead.

Rain is expected to continue overnight. Monday's forecast calls for a chance of rain throughout the morning, possibly turning to snow in the early afternoon.

The dense fog advisory will be lifted at 11 p.m. The flood advisory is in effect until 1 a.m.

–Shawn Shinneman