Weather in Fukuoka

On this site the months that score closest to a 22°C day, lighter rain, and moderate humidity are May, June, and September. Fukuoka is in Japan at 33.6°N. The 2001–2020 NASA POWER daily record describes a humid subtropical climate.

August is the warmest month (average 26.8°C, high 30.9°C) and January is the coolest (average 4.2°C, low 0.4°C). Rain is wet season runs from March to October, inside an annual total of 1900 mm. The wettest month is July at 357 mm; the driest is January at 70 mm.

When the score favours a visit

The three months with the highest comfort score are May, June, and September: May (18.2°C average, 158 mm, 79% humidity); June (22.1°C average, 299 mm, 83% humidity); September (23.1°C average, 189 mm, 85% humidity). They fall in calendar order. The score rewards averages near 22°C, lower rainfall, and humidity near 60%. It is a climate score, not a festival or price calendar.

If you want the wet season itself — fewer crowds, greener landscape, heavier rain — aim at March–October instead of the score.

Hot and cool months in Fukuoka

Fukuoka has a 22.6°C gap between its coolest monthly average (4.2°C in January) and its warmest (26.8°C in August). That is a northern-hemisphere pattern.

Across the year the mean afternoon high is 19.7°C. If you want the smallest day–night shock, look at months where the high and low sit close together; August nights still hold 22.8°C.

When Fukuoka gets wet

The wet season in Fukuoka starts in March and ends in October (March, April, May, June, July, August, September, and October). July is the core of it at 357 mm. January is the other extreme, with 70 mm.

Humidity peaks near 85%. That usually lines up with the wetter months rather than the hottest ones.

The calendar in Fukuoka

The year bottoms out in January. Plan for 0.4°C at night and 8.1°C in the afternoon. The wet season opens in March. Expect 118 mm and 11 rainy days, with nights around 3.4°C. In April, Fukuoka averages 18.7°C by day and 7.8°C at night, with 140 mm of rain. May: 23.6°C high, 12.8°C low, 158 mm rain, 79% humidity. June stands apart from the months beside it: 26.6°C / 17.6°C and 299 mm. July is the wettest month — 357 mm and 18 rainy days, with 85% humidity.

August is the warmest month. Afternoon highs average 30.9°C and nights settle near 22.8°C, with 204 mm of rain. September: 27.1°C high, 19.0°C low, 189 mm rain, 85% humidity. By October the wet season is ending. Fukuoka still sees about 109 mm, but the next month is usually leaner. November stands apart from the months beside it: 16.2°C / 7.5°C and 89 mm. December: 10.2°C high, 2.4°C low, 79 mm rain, 80% humidity.

Fukuoka and other cities in Japan

Hiroshima is about 207 km away: Fukuoka is 1.1°C warmer than Hiroshima in its hottest month and 344 mm wetter over the year than Hiroshima. Hiroshima’s wettest month is July (260 mm) versus July here.

Kobe is about 455 km away: Fukuoka is 0.6°C cooler than Kobe in its hottest month and 374 mm wetter over the year than Kobe. Kobe’s wettest month is July (204 mm) versus July here.

Osaka is about 483 km away: Fukuoka is 0.6°C warmer than Osaka in its hottest month and 147 mm wetter over the year than Osaka. Osaka’s wettest month is September (225 mm) versus July here.