See exactly when rain will start and stop with a minute-by-minute precipitation nowcast for the next hour.
21°
Light Rain
Feels Like: 21°
Min: 20°
Max: 24°
The next few hours will be overcast, with today reaching 24°C and dropping to 20°C. The coming days will be light rain throughout the day.
Compare today's weather with yesterday's data and track temperature trends over time.
Hourly Forecast
Daylight Hours
05:39
Sunrise
17:38
Sunset
Moon
Waxing Gibbous
14:52
Moonrise
00:37
Moonset
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View stargazing scoreWeather in Iiyama today, September 21, 2026
Expect unsettled, showery conditions in Iiyama on September 21, 2026 as rain moves through. The day opens on a wet note and needs flexible outdoor plans. Early hours look the most unsettled, with rain probability near 68% by 04:00. The thickest cloud arrives around 04:00, reaching about 100%.
Temperatures climb from an overnight low near 20°C toward a daytime high of about 24°C. Expect humidity between 86% and 95%, most humid near 04:00. Expect gentle winds, highest near 18:00 at 3.5 km/h.
Through the afternoon wet weather remains a factor, with rain chances near 96% around 19:00. Cloud also stays substantial, close to 100% near 12:00. Visibility stays generally good near 7.9 km on average, though it can drop toward 0.1 km in thicker cloud or showers. Expect sunrise at 05:39, sunset at 17:38, and 11 hours 58 minutes of sunlight today overall.
Taken together, Iiyama looks wet enough on September 21, 2026 that flexible outdoor plans work best, with temperatures peaking near 24°C.
Frequently asked questions about weather in Iiyama
How warm does it get in Iiyama?
The warmest month in Iiyama is August, with average high temperatures of 29°C. The average temperature during this period is around 24°C.
How cold does it get in Iiyama?
The coldest month in Iiyama is January, with average low temperatures of -5°C. The average temperature during this period is around -2°C.
What is the wettest time of year in Iiyama?
The wettest month in Iiyama is July, with an average of 275mm of precipitation.
What is the driest time of year in Iiyama?
The driest month in Iiyama is November, with an average of 119mm of precipitation.
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