Castle Hill Temperature by Month
Castle Hill in New South Wales, Australia sees moderate seasonal temperature shifts, with daytime highs between 19°C (66°F) in July and 29°C (84°F) in January, averaging 24°C (75°F) annually. Explore the full monthly breakdown below.
Castle Hill Monthly Temperatures
The moderate changes in the climate in Castle Hill ensure gradual weather shifts through each season. At night, temperatures drop to between 19°C (66°F) and 6°C (43°F) depending on the time of year.
The chart below illustrates the average maximum day and minimum night temperatures in Castle Hill by month:
The coldest point of the day usually falls between 4 AM and 6 AM, with temperatures peaking around 3 PM. January, the city's warmest month, gets 233 hours of sunshine.
The chart below shows the average temperature throughout the year:
Temperature: Castle Hill 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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Castle Hill vs World: Temperature Compared
Castle Hill's average annual maximum temperature is 24°C (75°F). To put that in context, here's how it compares to a few well-known destinations:
Rome, Italy averages 20°C (68°F) annually, with reliably warm summers and comfortable 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.
Osaka, Japan averages 22°C (72°F) annually, with hot humid summers, mild winters, and pleasant spring and autumn seasons.
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 Castle Hill?
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 Castle Hill, July is the coolest month, with average highs of 19°C (66°F) and humidity around 52% — considered moderate. In January, the warmest month, temperatures average 29°C (84°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 Castle Hill's weather — including monthly rainfall, sunshine hours, and humidity — visit our Castle Hill climate page.
