Hachijo Temperature by Month

The average annual maximum temperature in Hachijo, Japan is 22°C (72°F), with daytime highs ranging from 16°C (61°F) in February to 29°C (84°F) in August. This page covers monthly averages, day-night differences, and how Hachijo compares to cities worldwide.

The climate in Hachijo is dynamic, ranging widely from moderate in winter to comfortable in summer. Nights are significantly colder, with lows dropping from 27°C (81°F) in August to 11°C (52°F) in February.

The chart below illustrates the average maximum day and minimum night temperatures in Hachijo by month:

The coolest part of the day is typically between 4 AM and 6 AM, while 3 PM is usually the warmest, when solar heating is at its peak. August, the city's warmest month, averages 187 hours of sunshine.

The chart below shows the average temperature throughout the year:

Hachijo's average annual maximum temperature is 22°C (72°F). To put that in context, here's how it compares to a few well-known destinations:

Lisbon, Portugal averages 21°C (70°F) annually, warm summers, mild winters, and rain mainly in the cooler months.

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.

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 Hachijo, February is the coolest month, with average highs of 16°C (61°F) and humidity around 68%, considered high. In August, the warmest month, temperatures average 29°C (84°F) with 87% humidity, conditions that feel very 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.

For cities and regions with significant elevation, altitude is one of the biggest factors shaping local temperatures. As a rule of thumb, temperatures fall by around 6°C for every 1,000 metres gained, so a city at 2,000 metres will typically be around 12°C cooler than a city at sea level in the same region. Higher ground also tends to see more dramatic day-to-night temperature swings, since thinner air loses heat faster after sunset.

For more on Hachijo's weather, including monthly rainfall, sunshine hours, and humidity, visit our Hachijo climate page.