San Antonio Temperature by Month

The average annual maximum temperature in San Antonio, Ecuador is 19°C (66°F), with little variation between seasons. This page covers monthly averages, day-night differences, and how San Antonio compares to cities worldwide.

The temperature in San Antonio changes very little across the seasons, maintaining a similar climate throughout the year. Maximum daytime temperatures range from a pleasant 19°C (66°F) in December to a pleasant 20°C (68°F) in August. Nighttime lows range from 10°C (50°F) in August to 10°C (50°F) in December.

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

The coldest point of the day usually falls between 4 AM and 6 AM, with temperatures peaking around 3 PM. August, the city's warmest month, gets 257 hours of sunshine.

The chart below shows the average temperature throughout the year:

San Antonio's average annual maximum temperature is 19°C (66°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.

Glasgow, Scotland averages 13°C (55°F) a year, mild but often grey, with cold winters and rarely hot summers.

San Francisco, USA averages 19°C (66°F) annually, but with little seasonal variation, summers are often cool and foggy, winters mild.

Brisbane, Australia averages 26°C (79°F) a year, with warm winters and hot, humid summers.

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 San Antonio, December is the coolest month, with average highs of 19°C (66°F) and humidity around 81%, considered 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.

Whether a city sits on the coast or deep inland makes a significant difference to its climate. Coastal areas tend to have more stable temperatures year-round, large bodies of water absorb heat slowly in summer and release it gradually in winter, keeping extremes in check. Cities far from the sea don't benefit from that buffer, which is why continental climates tend to have hotter summers and colder winters than their coastal counterparts at the same latitude.

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