If you're planning a December trip to Ontario, the long-range outlook suggests pack layers rather than a parka-only strategy. The Old Farmers' Almanac has issued its December 2026 forecast for southern Ontario, and it points to a seesaw month: temperatures swinging up and down, regular flurries, and a rain-versus-snow split depending on which end of the province you're in.
The breakdown goes roughly like this. The first week of the month (Dec 1-7) starts with flurries across the province before turning milder with rain. From Dec 8 to 13, eastern Ontario gets flurries while the west sees snow, and colder air settles in everywhere. The stretch from Dec 14 to 22 brings mixed precipitation to the south — flurries in the east, rain showers in the west — with milder conditions on both sides. And for the holidays: Dec 23 to 31 looks like flurries and mild temperatures in the east, but snowy periods and proper cold in southwestern Ontario. So a white Christmas is a coin flip that depends largely on your postcode.
The headline numbers: an average December temperature of -2°C, about 1°C above normal, and total precipitation around 55 mm — roughly 15 mm below average in the east but 15 mm above it in the west.
There's a bigger climate story behind the milder numbers. Forecasters have been calling this one of Ontario's mildest winters in years, crediting a strong El Niño — the Pacific warming pattern that peaks between November and February and is known to scramble weather worldwide, bringing floods, droughts and heat to different regions. The Weather Network notes that in strong El Niño years, December temperatures in Toronto have averaged 2.6°C warmer than usual. That said, milder doesn't mean snow-free; a single well-timed storm can still define the season.
For travellers, this is genuinely useful intel. Toronto in early winter under El Niño tends to mean walkable, less brutally cold streets — good news if you're chasing the city's Christmas markets and pop-up bars without the usual deep-freeze. Skiers and snow-seekers, meanwhile, may want to watch conditions rather than assume the slopes are ready, and anyone dreaming of a snow-covered holiday should lean toward southwestern Ontario late in the month. Flexibility is the word: with rain and snow trading places week to week, waterproof footwear matters as much as a warm coat.
