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Hourly Forecast
Daylight Hours
05:49
Sunrise
17:48
Sunset
Moon
Waxing Gibbous
14:58
Moonrise
00:51
Moonset
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View stargazing scoreWeather in Kumagawa today, September 21, 2026
Kumagawa starts September 21, 2026 looking damp, with rain in the forecast and wetter spells likely at times. Waterproof kit is the safer call for early plans. Morning plans should assume damp conditions, as rain chances climb toward 94% around 10:00. Cloud cover is also at its densest near 06:00 at roughly 100%.
The temperature range runs from about 22°C up to 26°C. Relative humidity sits between 82% and 98%, reaching its peak around 09:00. A lighter breeze peaks around 15:00 near 8.5 km/h.
The second half of the day still looks unsettled, with rain probability around 100% by 13:00. Dense cloud near 99% at 12:00 keeps the feel grey. Visibility holds near 8.6 km, though it can fall to 0.2 km. Sunrise is at 05:49 and sunset at 17:48, giving 11 hours 58 minutes of sunlight today.
Taken together, Kumagawa looks wet enough on September 21, 2026 that flexible outdoor plans work best, with temperatures peaking near 26°C.
Frequently asked questions about weather in Kumagawa
How warm does it get in Kumagawa?
The warmest month in Kumagawa is August, with average high temperatures of 31°C. The average temperature during this period is around 28°C.
How cold does it get in Kumagawa?
The coldest month in Kumagawa is January, with average low temperatures of 3°C. The average temperature during this period is around 5°C.
What is the wettest time of year in Kumagawa?
The wettest month in Kumagawa is July, with an average of 261mm of precipitation.
What is the driest time of year in Kumagawa?
The driest month in Kumagawa is November, with an average of 94mm of precipitation.
