Weather in Nantes in December

A hard month. December is a hard month in Nantes, and worth planning around. Highs sit at 9.3 °C and the day is short; this is an indoors-with-excursions month, not an outdoors-all-day one.

December ranks 11 of 12 — near the bottom of Nantes's year. September is the month that works, and the swing between the two is 48 points, which is a different holiday rather than a slightly better one.

Rain on 14 days, 3 of them heavy. Enough to need a plan B, not enough to need a plan around it. Layers, and a genuinely waterproof outer — at 9.3 °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: 8 nights fall below freezing. Across the twenty years measured, the hottest December day reached 16.2 °C and the coldest night fell to -7.1 °C, and the wettest single day dropped 29 mm — roughly 32% of the month's rain in one day.

December is moderately variable: 19 mm in the driest year against 161 mm in the wettest, around an average of 91 mm. Roughly two Decembers in three land near that average, and the third does something else entirely.

Wind is light at 11.7 km/h, so the temperature on the page is close to the temperature on your skin, and humidity runs at 93%, which at 9.3 °C means damp rather than muggy — the kind of cold that gets into a coat and stays there.

How December sits in the year

Temperatures hold steady either side: 12.9 °C in November, 9.3 here, 8.9 in January. Nothing about the timing within the month matters much.

Daylight in December

December sits at the dark end of Nantes's year — 8.5 hours of daylight against 15.9 at midsummer, holding steady all month. Sightseeing days are genuinely shorter, and an itinerary built for summer will not fit.

Sea temperature

The sea sits at about 13.3 °C in December — too cold to swim without a wetsuit. The sea peaks at 20.5 °C in August and bottoms out at 11.1 °C — water lags the air by a month or two, which is why the best swimming often comes after the best weather.

How busy it gets

Off season. The genuine off season: cheapest by a distance, with the caveat that some tours and restaurants close entirely.

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

December in Nantes versus nearby

If Nantes is one option among several, the nearby comparison is worth making. Bordeaux is close enough to be a coin toss — within a degree on temperature, the same number of rain days. Le Havre is close enough to be a coin toss — within a degree on temperature, 2 days more rain.

So: December is a compromise. September is 47 points better and is what Nantes 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 Nantes

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