A significant blocking pattern developing over the north will force at least three shots of unseasonably cold air from the Arctic down into the Prairies later this week and again next week.
In addition to the turn to cold weather there will also be some snow from the Canadian Rockies to northwest Ontario.
1. The disturbance that brings in the first shot of cold air later this week will likely produce a swath of snow over the Canadian Rockies Tuesday night and into early Wednesday. Snowfall will be mostly light and on the order of 2-8 cm. There may also be some snow Wednesday morning near Calgary and points south.
2. This first shot of cold air will cover the Prairies from later Wednesday into Friday this week.
3. A Colorado low will track toward the Great Lakes by Tuesday night and this will bring a period of rain to much of southern and eastern Tuesday night into Wednesday.
This same storm will draw Atlantic moisture northward into the Maritimes Wednesday night with the potential for some heavier rainfall over New Brunswick, PEI and Nova Scotia.
4. A second cold front will push south through the Prairies on Sunday with another surge of cold air and snow showers to follow. A storm could form along the front and bring steadier snow to northwest Ontario by early Monday (Oct. 21).
5. While it is still early, there are signs of a third cold front charging south through the Prairies around Oct. 22 and this one could be the coldest of the three fronts with the potential for more snow as far east as central Ontario.
6. This pattern will be a very dry one for much of British Columbia over the next 7 to 10 days, so take advantage of that since we all know that it's not going to last as we head into November.
We will be releasing the AccuWeather.com Canada Winter Forecast on Wednesday. I will post some information about the forecast to my readers on Tuesday.
Any comments or questions please feel free to post them in the comment section below or on my twitter @BrettAWX and I will try to answer them.
I will also check into the AccuWeather.com Canada weather discussion forum from time to time. Sign up is free.
You can also reach me by email... right here.
Comments that don't add to the conversation may be automatically or manually removed by Facebook or AccuWeather. Profanity, personal attacks, and spam will not be tolerated.
Plenty of uncertainty with the weather pattern later in September.
Hot, dry conditions to prevail across BC into next week while rounds of cooler and showery weather spread from the eastern Prairies to Quebec.