Climate Overview
The climate in Hillsboro is temperate. The average annual temperature is 12°C and approximately 1701mm of precipitation falls per year. October is the wettest month, receiving around 408mm of rainfall. Hillsboro is in the Northern Hemisphere. Summer begins at the end of June and lasts through September. The summer months are: August, July, June. The coldest months are December, January, February, when temperatures can drop to 0°C. Light snow can occur between January and December.
Temperature
Temperatures in Hillsboro vary considerably across the year, with a 29°C difference between the coldest and warmest months. The warmest month is August, when average highs reach 29°C and the mean temperature sits around 20°C. The coldest month is December, when overnight lows fall to 0°C and the daily average is 2°C. On average, daily temperatures fluctuate by about 9°C between overnight lows and afternoon highs. The sharpest temperature change occurs between November and December, with a 8°C shift in average temperatures.
Precipitation
Hillsboro is a fairly wet location, receiving approximately 1701mm of precipitation annually, which averages out to around 142mm per month. The wettest month is October, averaging 408mm of rainfall. November and March also tend to see above-average precipitation. The driest month is August, with just 9mm. That's 399mm less than October, the wettest month. Rainfall is heavily concentrated in certain months, creating a distinct wet and dry season. Visitors should plan around these patterns, as the difference between peak and low months is dramatic. Light snowfall can occur between January and December, totalling around 43cm annually. December is the snowiest month with approximately 35cm.
Wind
Hillsboro is relatively calm, with an average annual wind speed of 2km/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 3km/h, though still comfortable for most outdoor activities. The calmest conditions occur in January, with average winds dropping to 2km/h, making it an ideal period for wind-sensitive activities. Wind conditions are fairly consistent throughout the year, varying by only 1km/h between the calmest and windiest months.
Seasons
52 days until Autumn
It is currently summer in Hillsboro, which began on June 21, 2026. Hillsboro 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 29°C, while the coldest stretch bottoms out in December near 0°C. Autumn is next, beginning on September 23, 2026 — 52 days from now.
Spring
Temperatures range from 5 to 22°C. Rainfall is heavy, totalling around 350mm across the season with a monthly average of 117mm. Winds are generally light, averaging 2km/h. An umbrella or waterproof jacket is advisable as spring showers are frequent.
Summer
Temperatures range from 11 to 29°C. Rainfall is relatively light, with around 81mm over the season and a monthly average of 27mm. Winds are generally light, averaging 2km/h. Comfortable clothing with a light layer for cooler evenings is all you need.
Autumn
Temperatures range from 7 to 23°C. Rainfall is heavy, totalling around 714mm across the season with a monthly average of 238mm. Winds are generally light, averaging 2km/h. A waterproof jacket and sturdy footwear are recommended as rain becomes more frequent.
Winter
Temperatures range from 0 to 12°C. Rainfall is heavy, totalling around 556mm across the season with a monthly average of 185mm. Expect around 41cm of snow accumulation during this period. Winds are generally light, averaging 2km/h. Warm winter clothing and waterproof boots are a must, and travel may be affected by snow.
Best Time to Visit
The best time to visit Hillsboro is during June, July, August and September, when the weather is most comfortable for travellers. During these months, average temperatures hover around 18°C with modest rainfall averaging 28mm per month. By contrast, December can be quite cold with temperatures dropping to 0°C. With minimal rainfall expected, you can pack light and plan outdoor activities with confidence.
Monthly Climate Data
The table below shows monthly climate averages for Hillsboro 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.
