Fog has rolled into Southwest Saskatchewan, bringing low visibility, lack of light, and an eerie calm to the sky. 

This form of water-saturated air is known as advection fog, which occurs as mild, moist air passes over cold ground. What exactly could happen with this interesting weather phenomenon is up in the air, and how long it may stay is unclear.  

Terri Lang, a meteorologist for Environment and Climate Change Canada, speaks on the matter. 

“Situations like this are really hard to call,” explained Lang. “It can be particularly bad in river valleys and that type of thing just because the cold air drains down. The fog tends to hang out in the lower elevations, and with the sun coming up, we may get some improvement, but then again at night, it may come back in. and we just have a bunch of weather systems kind of moving in and out and that can wreak havoc with the fog as well.” 

Lang explained that we are more likely to see these conditions if it is a milder winter, as the melted snow can put more moisture into the lowest parts of the atmosphere.  

“Certainly check the highway hotline before heading out because the visibility can get quite low and it's not good to be driving,” advised Lang. “Before heading out make sure that your car is ready for winter conditions and make sure that your headlights are on even during the daytime so that you can be visible.”