San Antonio Weather in September

San Antonio in September sees high temperatures, with highs around 25°C (77°F) and overnight lows of 17°C (63°F). With the rainy season in full effect, expect around 458 mm (18 in) of rainfall and regular showers throughout the month.

Rainfall in San Antonio in September

San Antonio is in the rainy season in September, with rain on around 24 days and an average of 458 mm (18 in). The rain this month falls heavily when it arrives, so waterproofs are worth keeping handy.

Temperature in San Antonio in September

In September, San Antonio sees high temperatures, with highs of 25°C (77°F). Nights drop to around 17°C (63°F). Overall, the month follows a fairly predictable daily temperature pattern. With lows of 17°C (63°F), nights are cool. If you're out after dark, an extra layer will keep you comfortable. The cooler air at night is also great for getting a good rest.

Sunshine in San Antonio in September

The month brings about 149 hours of sunlight, offering a comfortable mix of sun and rainy moments.

If you're looking for dry conditions and comfortable temperatures, September may not be the ideal month to visit San Antonio. Our weather planner can help you explore destinations with more pleasant weather conditions.

Select a Month

Check the conditions for any month of the year.

• January
• February
• March
• April

• May
• June
• July
• August

• September
• October
• November
• December

For a detailed overview over the year and the best time to visit Costa Rica, check out our San Antonio's climate page.

San Antonio Temperature in September

Min Temperature 17°C (63°F)  

Max Temperature 25°C (77°F)  

Chance of Rain 80%  

Precipitation 458 mm (18 in)  

Rainy days 24 days  

Humidity 85% *  

Sunshine 149 hours *  

Percentage Sunshine *  

* Data from: San José, Costa Rica (12 KM, 7 Miles).

What to Wear in San Antonio in September

Warm but pleasant conditions in San Antonio in September. Focus on lightweight, maybe with natural fabrics, cotton blend shirts, comfortable shorts, and breathable footwear. A light cover-up for sun protection is smart too. It's going to pour! Pack a good poncho and prepare for very wet conditions. Bring sunglasses since you'll have some sunny periods throughout the month

What To Do in San Antonio in September

We rated the following activities from 1 (least suitable) to 10 (best) to do.

Swimming

7/10

Cycling

7/10

Walking

7/10

Camping

6/10

Outdoor sports

7/10

Select a Month

Check the conditions for any month of the year.

• January
• February
• March
• April

• May
• June
• July
• August

• September
• October
• November
• December

For a detailed overview over the year and the best time to visit Costa Rica, check out our San Antonio's climate page.

More climate data for San Antonio

Temperature Rainfall Sunshine Humidity

See the full San Antonio climate overview or explore weather in Costa Rica.