Weather in Kumamoto

Planning a trip to Kumamoto or simply want to know what weather to expect? In this section, you will find the most up-to-date information: current reports, detailed forecasts, and visual charts to make your stay as comfortable as possible.

The climate in Kumamoto, located in Japan, can be characterised as humid subtropical, with four clearly defined seasons. The city offers diverse weather conditions throughout the year, which is important to consider when planning your trip.

Summer in Kumamoto (June-August) is usually hot and humid. The average air temperature during this period ranges from 22.8°C in June to 27.7°C in August, with maximum values often exceeding 30°C. June and July are also the months with the highest rainfall (11-12 mm) and the greatest number of rainy days (16-20 days), indicating a distinct summer rainy season. Winters (December-February), on the other hand, are quite mild, with average temperatures around 6.4°C - 7.5°C and significantly less precipitation (about 2-4 mm).

Spring (March-May) and autumn (September-November) in Kumamoto are transitional seasons with comfortable weather. In spring, the temperature gradually rises from 11.5°C to 19.4°C, and in autumn, it decreases from 24.7°C to 13.5°C. These periods are characterised by moderate rainfall and are a wonderful time to visit the city and its surroundings.

The temperature regime in Kumamoto is characterised by noticeable seasonal changes, offering diverse conditions throughout the year. The hottest month is traditionally August, when the average temperature reaches 27.7°C, with daytime highs often rising to 30.8°C and nighttime lows around 24.6°C. Conversely, the coldest period falls in January: the average temperature drops to 6.4°C, with nighttime cooling down to 3.3°C and daytime temperatures around 9.6°C.

The summer months in Kumamoto, from June to August, are distinguished by hot and humid weather. In June, the average temperature is 22.8°C (minimum 19.7°C, maximum 25.9°C), gradually rising by July to 26.5°C (minimum 23.9°C, maximum 29.2°C) and peaking in August. Daytime temperatures during this period are consistently high, and even nights remain quite warm, creating a tropical climate feel.

Winter in Kumamoto, covering December, January, and February, is quite mild and cool. Average temperatures range from 6.4°C in January to 7.5°C in December and February. Daytime highs in the winter months are usually in the range of 9.6°C - 11.1°C, while nighttime lows can drop to 3.3°C - 4.4°C. Although severe frosts are rare, the night chill is palpable. Daily temperature fluctuations in Kumamoto throughout the year are generally moderate, averaging 6-8°C between daytime highs and nighttime lows.

Precipitation in Kumamoto is distributed unevenly throughout the year, with a clearly defined wet season and drier periods. Understanding this dynamic will help you better plan your trip and choose appropriate clothing so that weather conditions do not catch you off guard.

The highest amount of rainfall traditionally occurs during the summer months, forming a distinct rainy season. The peak is in July, which is the wettest month of the year: on average, 12 mm of precipitation falls, and the number of rainy days reaches approximately 20. June is also characterised by high humidity — about 11 mm of rainfall and an average of 16 rainy days. During this period, rains can be quite intense and frequent, which is typical for the summer monsoon influence in the region.

On the other hand, the driest months in Kumamoto are January and December. Each of these months sees an average of just 2 mm of precipitation, with about 9 days with rainfall. Winter precipitation is generally lighter and less frequent than in summer. Spring (March-May) and autumn (September-November) months serve as transitional periods with moderate amounts of rainfall. For example, in October and November, about 3 mm falls, and in May – up to 7 mm. The number of rainy days in these seasons ranges from 9 to 14, making them generally comfortable for visiting.

When planning a trip to Kumamoto, it is important to choose your wardrobe correctly, taking into account the pronounced seasonal weather changes. In summer (June-August), it is hot and humid here, especially in June and July when the rainy season occurs. You will need light, breathable clothing made from natural fabrics, a hat, sunscreen, and, of course, a reliable umbrella or raincoat. Don't forget comfortable shoes, as there will be plenty of city exploring to do. In winter (December-February), the weather is cool, with average temperatures around 6-7°C, so warm items such as sweaters, a jacket, a hat, and a scarf will be very useful. Precipitation in winter is low, but a light waterproof jacket may come in handy.

Spring (March-May) and autumn (September-November) in Kumamoto are excellent times to visit with comfortable temperatures. However, the weather can be changeable, so the principle of layering your clothes will be your best friend. Bring t-shirts, long-sleeved shirts, a light sweater or fleece, as well as a windbreaker or light jacket. Rains are also possible in spring and autumn, so a compact umbrella won't go amiss. In May and June, the number of rainy days increases, so waterproof shoes or a spare pair will be very useful.

Regardless of the season, comfortable walking shoes are an absolute necessity, as Kumamoto and its surroundings offer many interesting places for hiking. Don't forget an electronics adapter if you need one. Given the humidity in the summer months and the potential use of air conditioning, a light scarf or shawl may be useful even in warm weather to protect against sudden temperature changes indoors.