Onjuku Temperature by Month
Onjuku, Chiba, Japan has an average annual maximum temperature of 20°C (68°F), ranging from 12°C (54°F) in February to 30°C (86°F) in August. Below you'll find a full monthly breakdown and a comparison with cities worldwide.
Onjuku Monthly Temperatures
The climate in Onjuku is dynamic, ranging widely from chilly in winter to comfortable in summer. Nights are significantly colder, with lows dropping from 25°C (77°F) in August to 6°C (43°F) in February.
The chart below illustrates the average maximum day and minimum night temperatures in Onjuku by month:
The minimum temperature is often recorded between 4 AM and 6 AM, while the highest temperature is usually reached at 3 PM, when the sun's heating effect is strongest. August, the warmest month, gets 190 hours of sunshine.
The chart below shows the average temperature throughout the year:
Temperature: Onjuku vs Japan
The map below shows the annual temperature across Japan. You can also select individual months if you want to compare a specific time of year.
very warm
warm
pleasant
moderate
cold
very cold
Onjuku vs World: Temperature Compared
Onjuku's average annual maximum temperature is 20°C (68°F). To put that in context, here's how it compares to a few well-known destinations:
Athens, Greece sits at 23°C (73°F) on average, with hot dry summers and mild winters characteristic of the Mediterranean.
Queenstown, New Zealand averages 10°C (50°F) annually — remember seasons are flipped, so its coldest months fall in June and July.
Shanghai, China averages 21°C (70°F) a year, with warm summers, mild winters, and a noticeable spring and autumn.
Adelaide, Australia averages 21°C (70°F) a year, with warm summers, mild winters, and relatively low rainfall year-round.
What Does the Temperature Feel Like in Onjuku?
Temperature alone doesn't tell the whole story — humidity plays a big role in how warm or cold it actually feels. High humidity in summer makes the heat feel more intense, particularly once temperatures climb above 25°C. In winter, the same humidity can make cold air feel sharper than the thermometer suggests.
In the cooler months, when temperatures drop below 10°C, high humidity makes the cold feel more cutting than it would in dry conditions.
In Onjuku, February is the coolest month, with average highs of 12°C (54°F) and humidity around 54% — considered moderate. In August, the warmest month, temperatures average 30°C (86°F) with 77% humidity — conditions that feel high. For a full picture, see our humidity page.
Climate temperature data is typically calculated as a 30-year average. This smooths out year-to-year variability and gives a more reliable picture of what a place is actually like, rather than what happened in any single unusual year.
The readings come from a range of sources — land-based weather stations, ocean buoys, ships, and satellites. That data is collected by weather services around the world, then pooled, quality-checked, and averaged to produce the climate records you see here.
Seasonal temperature shifts influence more than just how warm it feels — they also drive changes in rainfall, cloud cover, and wind patterns throughout the year.
Warmer air holds more moisture, which tends to mean heavier or more frequent rain during the warmer months. When temperatures drop in winter, any precipitation that does fall is more likely to come as snow or sleet, though in Onjuku this rarely lasts long on the ground.
For more on Onjuku's weather — including monthly rainfall, sunshine hours, and humidity — visit our Onjuku climate page.
