Nagasaki weather in December
December in Nagasaki: cold, rainy, with clean air — a good time to visit.
Updated September 2026 · climate normals from ERA5 reanalysis
#6 of 12 months in Nagasaki · #781 of 1413 destinations to visit in December · comfort 68/100 (tier C)
- Days
- 13°C
- Nights
- 6°C
- Wet days
- 10
- Sun
- 6.1 h
- Humidity
- 67%
- Daylight
- 10 h

Traveller notes on Nagasaki in December
Notes from nearby Fukuoka (107 km away)
Nagasaki doesn't have its own notes for December yet — these are about Fukuoka, close enough to share the season.
Regulars are specific that northern Kyushu runs genuinely dry and clear this month, more sunny days than much of the rest of the country in winter, with coastal cities along this stretch relatively mild compared with inland Japan. Our row backs that cool, still-mild read, 12.4C over 5.8C nights feeling 2C, with 58.3mm of rain across 8.3 days and a trace of snow, 1.2cm. Regulars are consistent snow in the city itself is genuinely rare early in the month, appearing only in some years and largely dependent on exactly where a Siberian cold front settles, with one recent year seeing first snow in November and the next seeing none until deep December. Layers over a warm coat remain the standard advice given how much year-to-year variation regulars report. The sea sits at a cool 15.3C. The record: humidity 73 percent, 6.4 hours of sun, a 14 kph wind and AQI 49.
Other months in Nagasaki
Forum posters consistently rate April as one of the best months to visit Japan, generally warm and springlike, though posters are direct that conditions can still turn variable enough to want a coat on some days, whether from cooler temperatures or rain. Posters describe typical April days as comfortable in shirtsleeves with a light jacket in the daypack for evenings, rather than requiring a heavy winter coat, and note that on a sunny day temperatures can climb into the mid-20sC. Posters discussing Kyushu specifically, where Nagasaki sits, describe the region as reliably warm by late March into April compared with much of the rest of Japan. Posters generally rate April as a comfortable, mild time to visit Nagasaki, with a light jacket the main packing recommendation for cooler mornings and evenings.
October is widely rated one of Japan's two best months, and Kyushu — Nagasaki, Fukuoka, Kumamoto, Kagoshima — is the part of the country the forum points at when someone wants October warmth specifically. Nagasaki bears that out: days near 23°C and nights that stay unusually mild at about 18, well above what Honshu offers by then, with the sea still at 25°C. Early October runs warm and late October cools, so a light jacket for the evening covers it. The one risk worth planning around is typhoons, which can deliver a day or two of heavy rain before things return to normal.
Add your own note from Nagasaki's card on the map.
Nagasaki climate normals — December
Monthly averages from ERA5 reanalysis. AQI is the mean US Air Quality Index for the month.
Crowds in Nagasaki in December
How busy the place itself is — school and mass holidays, the months an editor tagged, and how sought-after the weather makes them. Never part of the comfort score.
BusyWinter break (fuyuyasumi) in Japan, school holidays in 4 of the markets that fill it(estimated)
Peak crowdsBusyShoulder seasonQuiet
Best months for Nagasaki's weather
Ranked by this destination's own climate comfort score across the year — a different thing from how busy it gets (see Crowds above).
Fair weatherNagasaki's best weather comes in April, October and November — separate windows, not one continuous season.
Best weatherFair weatherToughest weather
What's on in Nagasaki in December
Recurring seasonal events, natural spectacles, closures and holidays — curated and sourced.
- Rule
Gunkanjima landings are weather-called
1 Jan – 31 DecClosuresBoats to Hashima sail most days but only land when the swell allows, and the call is made at the pier. Winter is when it fails most; leave a spare day if the island is the reason you came. Source ↗
Nearby, and something's on
Within 300 km of Nagasaki — a day trip or a short hop — with something on this month. Never part of the comfort score.
Where is Nagasaki?
Nagasaki in December — FAQ
- Is December a good time to visit Nagasaki?
- December in Nagasaki: cold, rainy, with clean air — a good time to visit. It ranks #6 of 12 months for Nagasaki on SeasonMap's comfort score (68/100).
- What is the weather like in Nagasaki in December?
- In December, Nagasaki averages a daily high of 12.8°C and a low of 5.6°C, with about 81.8 mm of rain over roughly 9.5 rainy days.
- What is the air quality in Nagasaki in December?
- Nagasaki has a mean US Air Quality Index of about 42 in December.
Within 300 km: Fukuoka's Autumn leaves around 15 Nov – 8 Dec, and Kagoshima's Cranes winter at Izumi around 1 Nov – 25 Mar.