Weatheo
  • Koga
  • Weather by month

Koga Weather by Month

Average temperatures, rainfall and humidity for Koga, Japan, month by month, built from OpenWeather’s historical records. Use it to see what a typical Koga month looks like before you travel — then check the live Koga forecast for the days ahead.

Warmest month

August

33°C average high

Coolest month

January

1°C average low

Wettest month

June

140 mm of rain

Driest month

January

23 mm of rain

Average temperature and rainfall in Koga by month

Averages of the daily highs and lows recorded in each month, with total rainfall, mean humidity and mean wind speed.

MonthAvg highAvg lowRecord low / highRainfallHumidityWind
January10°C1°C-9°C / 18°C
23 mm
56%9 km/h
February11°C1°C-10°C / 23°C
30 mm
55%10 km/h
March15°C5°C-6°C / 26°C
65 mm
61%10 km/h
April19°C10°C-1°C / 29°C
89 mm
65%11 km/h
May24°C15°C3°C / 35°C
85 mm
69%11 km/h
June27°C19°C8°C / 39°C
140 mm
76%9 km/h
July31°C23°C16°C / 40°C
136 mm
75%9 km/h
August33°C25°C14°C / 41°C
98 mm
75%10 km/h
September28°C21°C10°C / 38°C
108 mm
77%10 km/h
October22°C14°C1°C / 33°C
88 mm
72%9 km/h
November17°C9°C-6°C / 28°C
45 mm
67%7 km/h
December12°C4°C-8°C / 22°C
24 mm
60%8 km/h

Best time to visit Koga

The most comfortable time to visit Koga is generally April to May and October, balancing mild daytime temperatures against the driest stretch of the year. The city has strongly marked seasons and rain concentrates around June, totalling about 930 mm a year.

Travellers who prefer heat should aim for August, when highs average 33°C. June is the month to avoid if rain would spoil your plans — it averages 140 mm, roughly 6× the rainfall of the driest month (January).

Source: OpenWeather historical and statistical weather data. Values are long-term averages, not a forecast — see the Koga forecast for what is happening now.