Climate Overview
The climate in Iitomi is temperate. The average annual temperature is 11°C and approximately 2250mm of precipitation falls per year. Iitomi receives a notable amount of rainfall throughout the year, including during its driest month. Iitomi is in the Northern Hemisphere. Summer begins at the end of June and lasts through September. The summer months are: August, July, September. The coldest months are January, February, December, when temperatures can drop to -5°C. Snowfall occurs from January to December, with around 111cm accumulating over the season.
Temperature
Temperatures in Iitomi vary considerably across the year, with a 32°C difference between the coldest and warmest months. The warmest month is August, when average highs reach 27°C and the mean temperature sits around 22°C. The coldest month is January, when overnight lows fall to -5°C and the daily average is -1°C. Daily temperature variation is modest, with an average difference of 8°C between highs and lows. The sharpest temperature change occurs between September and October, with a 6°C shift in average temperatures.
Precipitation
Iitomi is a very wet location, receiving approximately 2250mm of precipitation annually, which averages out to around 188mm per month. The wettest month is July, averaging 341mm of rainfall. September and June also tend to see above-average precipitation. The driest month is December, with just 72mm. That's 269mm less than July, the wettest month. Precipitation varies noticeably between seasons, with the second half (July to December) of the year generally seeing more rainfall. Snowfall is a regular feature from January to December, with around 111cm accumulating over the season. March typically sees the most snow at around 34cm.
Wind
Iitomi is relatively calm, with an average annual wind speed of 8km/h. For context, sustained winds below 12km/h are generally light, while anything above 25km/h is considered strong. The windiest month is March, averaging 10km/h, though still comfortable for most outdoor activities. The calmest conditions occur in August, with average winds dropping to 7km/h, making it an ideal period for wind-sensitive activities. Wind conditions are fairly consistent throughout the year, varying by only 3km/h between the calmest and windiest months.
Seasons
89 days until Summer
It is currently spring in Iitomi, which began on March 20, 2026. Iitomi is in the Northern Hemisphere, where spring begins in March, summer in June, autumn in September, and winter in December. The warmest period peaks in August at around 27°C, while the coldest stretch bottoms out in January near -5°C. Summer is next, beginning on June 21, 2026 — 89 days from now.
Spring
Temperatures range from 0 to 19°C. Rainfall is heavy, totalling around 550mm across the season with a monthly average of 183mm. Winds are generally light, averaging 9km/h. An umbrella or waterproof jacket is advisable as spring showers are frequent.
Summer
Temperatures range from 14 to 27°C. Rainfall is heavy, totalling around 835mm across the season with a monthly average of 278mm. Winds are generally light, averaging 8km/h. Light, breathable clothing is ideal — perfect conditions for outdoor activities.
Autumn
Temperatures range from 3 to 23°C. Rainfall is heavy, totalling around 615mm across the season with a monthly average of 205mm. Winds are generally light, averaging 7km/h. A waterproof jacket and sturdy footwear are recommended as rain becomes more frequent.
Winter
Temperatures range from -5 to 6°C. Precipitation is moderate at around 251mm for the season, averaging 84mm per month. Expect around 66cm of snow accumulation during this period. Winds are generally light, averaging 9km/h. Warm winter clothing and waterproof boots are a must, and travel may be affected by snow.
Monthly Climate Data
The table below shows monthly climate averages for Iitomi based on historical weather data. Min and max temperatures represent typical overnight lows and afternoon highs for each month, shown in degrees Celsius (°C). Precipitation is measured in millimetres (mm) and indicates the average total rainfall per month. Snow is measured in centimetres (cm) and reflects average monthly snowfall accumulation. Wind speed is the average sustained speed in kilometres per hour (km/h). All values are based on averages from over 10 years of historical weather data. The current month is highlighted for quick reference.
