San Isidro Weather in September

With daytime temperatures of 24°C (75°F) and nighttime lows of 17°C (63°F), September in San Isidro brings high temperatures during the day. Do keep in mind that September is part of the rainy season, with frequent and often heavy rainfall.

Rainfall in San Isidro in September

As part of the rainy season, San Isidro sees around 23 days of rain in September, with an average of 655 mm (26 in). Showers during the rainy season tend to be heavy and can come down intensely. An umbrella is often not enough, so a poncho or waterproof jacket is a better choice.

Temperature in San Isidro in September

Expect highs of 24°C (75°F) in San Isidro in September, with nights dropping to around 17°C (63°F). This kind of day-to-night contrast is typical for this time of year. 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 Isidro in September

The area enjoys a balanced 153 hours of sunlight, ensuring it's neither too rainy nor too sunny.

September in San Isidro has its charm. However, if you're seeking pleasant, dry and sunny weather, our weather planner can help you explore other destinations in the world.

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

San Isidro Temperature in September

Min Temperature 17°C (63°F)  

Max Temperature 24°C (75°F)  

Chance of Rain 77%  

Precipitation 655 mm (26 in)  

Rainy days 23 days  

Humidity 83% *  

Sunshine 153 hours *  

Percentage Sunshine *  

* Data from: Quepos, Costa Rica (50 KM, 31 Miles).

What to Wear in San Isidro in September

Pleasant temperatures in September mean you can pack light but flexibel pieces. Think cotton t-shirts, comfortable walking shorts, and one warmer layer for evenings. A light sweater or denim jacket works well. Heavy rain is guaranteed, please bring a good poncho and waterproof everything! Sunglasses could come in handy during the sunnier parts of your trip.

What To Do in San Isidro in September

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

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 Isidro's climate page.

More climate data for San Isidro

Temperature Rainfall Sunshine Humidity

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