Temperatures are climbing fast in Southern Ontario this week, and with an above-seasonal high of 7 C forecast for Toronto on Friday, one couldn't be blamed for planning a weekend filled with outdoor fun.

Don't do that, though: Warm as the air may be over the next few days, it'll also be quite wet thanks to a low pressure system developing over the southern United States.

This messy system is only expected to intensify as it moves north, bringing heavy rains to southern Ontario by Saturday.

"Widespread heavy rain and very mild temperatures are expected for southern Ontario, with the steadiest of it falling through the afternoon and evening hours," writes The Weather Network of this weekend's forecast.

"Before the rain however, a period of snow or freezing rain threatens northern sections of the GTA from Orangeville to Barrie, with an extended period of snow and ice likely into northern cottage country as well."

Once the rain storms pass through, we can expect what meterologists describe as "blustery and more seasonal conditions" in downtown Toronto.

Gusty winds and lake-effect snow are expected to begin developing on Sunday, and should continue into next week as temperatures fall back down to more seasonal levels.

"Near seasonal temperatures are expected for most of next week," said Weather Network meteorologist Dr. Doug Gillham on Thursday. "However, at this point, it looks like above seasonal temperatures could return to our region for the week leading up to Christmas."

As of right now, the week of December 21 is looking quite sunny and mild with temperatures hovering around 1 or 2 C. The chances of seeing snow on December 25 are looking slimmer and slimmer, but given how quickly the weather changes around here, there's still hope for a white Christmas yet.