Locally Dense Fog Possible Tuesday Night

Update:  Dense Fog Advisory now issued for all of Northern Illinois through 10am Wednesday morning.  Take it slow on the morning commute.

Just In: A Dense Fog Advisory has been issued for Winnebago, Boone, Ogle, Lee, DeKalb and McHenry counties beginning 9pm Tuesday night and lasting through Wednesday morning.

Parts of Northern Illinois experienced dense fog Tuesday morning, with some areas south of Rockford not completely clearing until the afternoon.

While most did see sun during the afternoon, it did have an impact on high temperatures.  In Janesville, where there was very little fog, highs reached the low 70's.  In Rochelle, the high was only 64 degrees!  A result of the fog and low, stratus clouds.

Dew points today have risen to the low 50's, increasing the amount of moisture in the atmosphere.  You may have even noticed a little haze when the sun was setting tonight.  With light winds and clear skies this evening, temperatures will fall near the dew point reading.  This will allow fog to develop for the Wednesday morning commute.

Depending on how long the fog lasts into the morning, and possibly into the afternoon, it will have an impact on high temperatures Wednesday.  As it looks right now, most of the fog should be gone by mid to late morning.  Temperatures will still warm above average, but we may only reach the middle to upper 60's rather than the 70's.  If, however, the fog clears faster highs will warm into the low 70's.