With a high of -1 C, Wednesday will be the coldest day of the next five

Freezing fog caused limited visibility across Calgary early Wednesday.

Freezing fog can develop when there is minimal wind, along with air temperatures and surface temperatures that are both at or below freezing.

If the dew point and air temperature are similar, the air above the surface can become saturated with supercooled water droplets and fog will form. When those droplets land on certain surfaces (e.g. roadways, sidewalks, handrails and trees) those droplets often freeze contact and a layer of ice will form.

In some cases, black ice can form and road conditions will quickly deteriorate.

Wind will help mix out that fog throughout the morning but conditions are expected to remain mildly unsettled on Wednesday.

Calgary’s forecast high of -1 C is only slightly cooler than the seasonal high of 0 C, but with cloud cover and a stronger wind, it feel more like a typical December day.

A strengthened ridge of high pressure moving across southern British Columbia will extend east and north over the next 24 hours. Under that ridge, warmer air will flow in from the Pacific basin and help elevate temperatures in southern Alberta on Thursday and Friday.

The end of the week will include more melting in Calgary with mostly sunny conditions and westerly winds. Light and scattered snow is possible on Saturday and Sunday.