San Antonio Temperature by Month

San Antonio, Heredia, Costa Rica has a consistently comfortable climate year-round, with daytime highs averaging 25°C (77°F). Below you'll find a full monthly breakdown and a comparison with cities worldwide.

San Antonio enjoys a stable climate with temperatures staying pretty much the same throughout the year. Maximum daytime temperatures range from a comfortable 25°C (77°F) in November to a comfortable 27°C (81°F) in April. Nights are consistently cool, with lows between 17°C (63°F) and 16°C (61°F).

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. April, the city's warmest month, gets 241 hours of sunshine.

The chart below shows the average temperature throughout the year:

San Antonio'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:

Seville, Spain averages 23°C (73°F) a year, one of the warmer cities in Western Europe, with long hot summers.

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

Seoul, South Korea averages 18°C (64°F) a year, with four clear seasons, cold winters, and hot humid summers.

Perth, Australia averages 25°C (77°F) annually, with a classic Mediterranean climate, hot dry summers and mild wet winters.

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, November is the coolest month, with average highs of 25°C (77°F) and humidity around 79%, considered high. In April, the warmest month, temperatures average 27°C (81°F) with 70% 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.

Global average temperatures have risen by around 1.2°C since the pre-industrial era, and the effects are visible across many regions. Winters are milder on average, with fewer frost days and less snow in many parts of the world. Heatwaves are more frequent and more intense, and Europe's summers of 2018, 2019, and 2020 all set records.

Summers are also getting drier in some areas, while winter rainfall has increased in others. This contributies to higher river levels and more flooding. In many countries, spring arrives earlier and autumn lasts longer. It has knock-on effects for wildlife, agriculture, and local ecosystems.

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