The fog that has covered much of southeast Saskatchewan has resulted in a picturesque winter scene, with frost covering nearly everything.  

This frost does normally fall off like snow as the day goes on, but after a few consecutive days of fog advisories, which means a lot of moisture in the air, it is building up.  

The increase in humidity is being caused by an inversion system that is hanging over the southeast, explained Terri Lang, a meteorologist with Environment and Climate Change Canada. 

"The moisture tends to get trapped under what we call an inversion. That means the temperature is colder at the surface, but actually increases as you go through the atmosphere, which is the opposite of what it usually does. What that inversion does is it traps any moisture that's floating around." 

While many attribute the rime to hoarfrost, that's actually specifically only when the frost patterns appear while there's a clear sky, not when there's fog in the air. 

"What happens with the fog is it tends to produce what we call rime icing. So, the moisture comes out of the fog, and it attaches itself to anything it can," said Lang, "So that's cars - so you have to scrape your car, even if those frost patterns are pretty; trees, that type of thing." 

While the patterns can often be pretty, they do also pose a threat to some infrastructure that can get weighed down. 

"Makes for very nice pictures, but extended periods of rime icing can actually be detrimental because if it goes on too long it builds up too much on the power lines and that type of thing," said Lang, "So it can actually lead to some issues." 

There is more fog expected for the next day or so, with temperatures above seasonal for this time of year. This means we could see some more of the rime ice develop before it starts to disappear.  

You can get more details on the Discover Weyburn Weather page.  

With files from Scott Boulton/discoverestevan.com