Weather in Tokyo in December

Shoulder season. December sits in between. You will get good days and you will lose some. Highs sit at 11.6 °C and the day is short; this is an indoors-with-excursions month, not an outdoors-all-day one.

December ranks 7 of 12 in Tokyo: past the worst of the year but short of May, which is the month to book if the dates are open.

Rain on 7 days, 2 of them heavy. Enough to need a plan B, not enough to need a plan around it. Layers, and a genuinely waterproof outer — at 11.6 °C the difference between a good day and a miserable one is entirely down to what you are wearing.

What the averages hide

The averages here are honest — no hidden extremes worth planning around. Across the twenty years measured, the hottest December day reached 23.3 °C and the coldest night fell to -2.1 °C, and the wettest single day dropped 142 mm — roughly 171% of the month's rain in one day.

December is moderately variable: 8 mm in the driest year against 192 mm in the wettest, around an average of 83 mm. Roughly two Decembers in three land near that average, and the third does something else entirely.

Wind is light at 8.9 km/h, so the temperature on the page is close to the temperature on your skin, and humidity runs at 78%, which at 11.6 °C means damp rather than muggy — the kind of cold that gets into a coat and stays there.

How December sits in the year

The month is on the way down: 5.2 °C cooler than November, with January dropping another 2.6 °C. The first week and the last are not the same trip.

Daylight in December

December sits at the dark end of Tokyo's year — 9.8 hours of daylight against 14.6 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 21 °C in December — comfortable for a proper swim. The sea peaks at 27.8 °C in August and bottoms out at 18 °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

Shoulder. The value months — prices ease off and you get the place closer to itself.

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

December in Tokyo versus nearby

If Tokyo is one option among several, the nearby comparison is worth making. Utsunomiya is the weaker option in December — 2.2 °C cooler, 1 day less rain. Hamamatsu is close enough to be a coin toss — within a degree on temperature, the same number of rain days.

So: December works, with May the better month by 15 points if the dates can move. If they cannot, nothing here should stop you booking.

Every month in Tokyo

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