Why the rime frost has stuck around in Sask.

Saskatchewan has played host to some unusual weather over the past week. A temperature inversion at the surface, where cold air lies below warmer air,led to low-level cloud and fog which drove down visibility across the southern half of the province.

With air temperatures well below the freezing mark, the water droplets in the air froze to treesand other vegetation, leaving gorgeous rime frost coating Saskatchewan's landscape.

• November 2017:Regina residents check out frost, fog covering city

Now, a few days later, the picturesque frost is still clinging on.

Why has the rime frost stuck around?

Over the last few days we have seen a stagnant, moisture-rich air mass over the prairies. Combined withthat temperature inversion, it led to the persistent fog.

With very light winds both at ground level and at high levels in the atmosphere and little sunshine over the weekend, Saskatchewan was trapped in a virtual weather snow globe. Not much change meantday after day of beautiful, frosty trees.

The rime frost really built up thanks to the extended time in the freezing fog. Some trees even lostbranches under the weight.

How long will the frost last?

We finally have some movement in our atmosphere, meaning that the low level moisture will be flushed out of the province with winds out of the west. Though the south saw a little sun Monday, more snow is on the way with cooler temperatures Tuesday and Wednesday so we likely won't see much of that frost melting away.

What we will see into Tuesday and Wednesday is stronger winds moving in. Those gusty winds will blow some of the rime frost off the trees this week.