Hornsby Temperature by Month
The average annual maximum temperature in Hornsby, New South Wales, Australia is 23°C (73°F), with daytime highs ranging from 18°C (64°F) in July to 28°C (82°F) in January. This page covers monthly averages, day-night differences, and how Hornsby compares to cities worldwide.
Hornsby Monthly Temperatures
Hornsby sees moderate fluctuations in temperatures, making each season distinct yet not extreme. Nights are considerably cooler, with lows ranging from 19°C (66°F) in January to 8°C (46°F) in July.
The chart below illustrates the average maximum day and minimum night temperatures in Hornsby by month:
Daily lows are most common between 4 AM and 6 AM. By 3 PM temperatures reach their daily high, driven by peak solar heating. January, the warmest month of the year, receives 233 hours of sunshine.
The chart below shows the average temperature throughout the year:
Temperature: Hornsby vs Australia
The map below shows the annual temperature across Australia. You can also select individual months if you want to compare a specific time of year.
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Hornsby vs World: Temperature Compared
Hornsby's average annual maximum temperature is 23°C (73°F). To put that in context, here's how it compares to a few well-known destinations:
Barcelona, Spain has an annual average of around 21°C (70°F), with warm summers and mild, fairly short winters.
Zermatt, Switzerland averages just 4°C (39°F) annually due to its altitude, with very cold winters and cool summers even at its warmest.
Beijing, China averages 20°C (68°F) annually, but with big seasonal swings — very cold winters and hot summers.
Perth, Australia averages 25°C (77°F) annually, with a classic Mediterranean climate — hot dry summers and mild wet winters.
What Does the Temperature Feel Like in Hornsby?
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 Hornsby, July is the coolest month, with average highs of 18°C (64°F) and humidity around 52% — considered moderate. In January, the warmest month, temperatures average 28°C (82°F) with 61% 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.
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 Hornsby's weather — including monthly rainfall, sunshine hours, and humidity — visit our Hornsby climate page.
