What is freezing fog?

Last night as well as this morning mid-Missouri saw dense fog settle into the area as temperatures dropped towards the dew point under calm conditions. Fog is a low lying cloud which is made up of visible cloud droplets suspended just above the surface.

When temperatures drop below freezing while fog is present we get what is know as freezing fog. The cloud droplets become supercooled once they fall below freezing. The fog won’t freeze immediately when suspended in the air, but once it touches a surface where temperatures are below freezing it turns to ice.

Often times this produces dangerous conditions. Freezing fog can create thin layers of ice on roadways, in addition to creating reduced visibility. These slick conditions can go unseen, which is what is known as black ice.

When driving in fog it is important to slow down, but especially so once those temperatures drop below freezing. In addition, drivers should not use high beams as that can cause even more of a blinding effect. Although, drivers should use their low beams to make the vehicle visible to others on the road. With limited visibility use pavement lines to guide your car when driving.

Tonight fog is possible to develop yet again through the overnight hours, but temperatures will remain above freezing.