Weather in Banff in December

The month to avoid. December is the month most people should skip in Banff. Highs sit at -6.1 °C and the day is short; this is an indoors-with-excursions month, not an outdoors-all-day one.

December ranks 9 of 12 in Banff: past the worst of the year but short of August, which is the month to book if the dates are open.

This is persistent light rain rather than storms: 14 wet days but only 0 heavy ones. It rarely cancels anything outright, and it rarely fully clears either. A jacket beats an umbrella. Layers, and a genuinely waterproof outer — at -6.1 °C the difference between a good day and a miserable one is entirely down to what you are wearing.

What the averages hide

Averages flatten a month, and this one hides a few things: 31 nights drop below freezing, so anything left outside stays frozen. Across the twenty years measured, the hottest December day reached 5.5 °C and the coldest night fell to -36.5 °C.

December is statistically steady but not small: the year-to-year variation is modest in relative terms, yet the wettest December on record still delivered 76 mm against 27 mm in the driest. In a month this wet, even a tame spread is a lot of rain in absolute terms — the 48 mm average is a reasonable planning figure, not a promise.

Wind is light at 2 km/h, so the temperature on the page is close to the temperature on your skin, and humidity runs at 96%, which at -6.1 °C means damp rather than muggy — the kind of cold that gets into a coat and stays there.

How December sits in the year

This is a turning point in the year — November and January sit on opposite sides of it, so the month contains the change rather than following it.

Daylight in December

December sits at the dark end of Banff's year — 7.9 hours of daylight against 16.5 at midsummer, losing 0.4 hours across the month. Sightseeing days are genuinely shorter, and an itinerary built for summer will not fit.

An inland climate

With no coast nearby, the year swings a fair way — 35.3 °C between the warmest afternoons and the coldest nights, wider than any coastal city at this latitude would manage. At 1388 m the air is thin enough to matter — sun that burns faster than the temperature suggests, and nights that cool off quickly.

How busy it gets

Quiet. Few other visitors, cheaper rooms, and a real chance some seasonal operators are shut.

Crowd levels are estimated from climate desirability and school-holiday calendars, not from visitor numbers.

December in Banff versus nearby

If Banff is one option among several, the nearby comparison is worth making. Calgary is a better bet in December — 4.4 °C warmer, 9 days less rain. Lethbridge is a better bet in December — 4.8 °C warmer, 6 days less rain.

So: December is a compromise. August is 62 points better and is what Banff is actually like at its best — worth moving the trip for if that is possible, and worth adjusting expectations for if it is not.

Every month in Banff

See all twelve months in Banff, or where else to go in December.