The City of Vancouver's snow removal crews are already out spreading salt and sand on major bus routes and roads near schools and hospitals in anticipation of a dump of snow that could arrive over the Family Day long weekend.

As of Friday afternoon, Environment Canada said the cold Arctic air experienced over much of the South Coast this past week is going to be replaced with a milder Pacific system by Tuesday, but the approaching system is "complex."

Environment Canada's weather models show that a pulse of moisture will hit Vancouver Island and the Lower Mainland Sunday, but the model's outcomes have been flip-flopping.

Sunday's weather shift could amount to rain or possibly up to 10 centimetres of snow across parts of southwestern B.C. On Monday, some areas could possibly see freezing rain.

"The fine details of this process are often not predictable until the day of the storm, if at all," Environment Canada said in Friday's weather statement for Metro Vancouver. "The regions affected, the amount of snow that falls prior to the change to freezing rain, and the duration of the freezing rain are the forecast challenges."

The weather service says "a variety of weather warnings are possible," and it won't know more until the new Pacific system gets much closer.

But, it's very likely, by Tuesday "significant rain" will start to fall on the South Coast.

The take-away? If you're going to be on the South Coast, plan for some snow or freezing rain Sunday or Monday just in case, and have alternate plans at the ready if you are travelling. Also, get ready for more wet, stormy and warmer weather starting Tuesday.

B.C. Family Day long weekend weather outlook - South Coast - Monday

A Pacific weather system will bring precipitation, shown in green, by Family Day on Monday — the only question is: will it come down as snow, rain or something else in-between?

With files from the CBC's Johanna Wagstaffe