Aliso Viejo (CA) Temperature by Month

Aliso Viejo in California, United States of America sees moderate seasonal temperature shifts, with daytime highs between 19°C (66°F) in December and 30°C (86°F) in September, averaging 25°C (77°F) annually. Explore the full monthly breakdown below.

The climate in Aliso Viejo experiences moderate temperature changes, with mild shifts between seasons. At night, temperatures range from 17°C (63°F) in September to 8°C (46°F) in December.

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

From around 4 AM to 6 AM temperatures are at their lowest; by 3 PM they've climbed to their daily peak. September, the warmest month, averages 290 hours of sunshine.

The chart below shows the average temperature throughout the year:

Aliso Viejo's average annual maximum temperature is 25°C (77°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.

Buenos Aires, Argentina averages 23°C (73°F) a year, with hot summers and mild winters, and seasons reversed compared to Europe.

Adelaide, Australia averages 21°C (70°F) a year, with warm summers, mild winters, and relatively low rainfall year-round.

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 Aliso Viejo's weather, including monthly rainfall, sunshine hours, and humidity, visit our Aliso Viejo climate page.