There’s the potential to see freezing fog overnight and into Tuesday morning. With the sky clearing in spots, the wind turning lighter and temperatures falling to the 20s, fog may develop.

Any fog that does develop will lead to low visibility in locations. Areas that will be prone to see the thicker fog and lowest visibility will be along the river valleys, especially along the Tennessee River. Along with the potential for low visibility, freezing fog could allow for a thin layer of ice to form on roads. If you are heading out early Tuesday morning, make sure to allow yourself plenty of time.

So what exactly is freezing fog? Fog is made up of tiny supercooled water droplets which can remain liquid even when the temperature is below freezing. If the fog is thick enough, these water droplets can freeze onto surfaces that are below freezing, especially elevated surfaces like bridges and overpasses.

We’ll need to monitor the potential for black ice. Extreme caution should be taken if traveling as black ice is difficult to spot.