San Marcos Weather in September

What's the weather like in San Marcos (San José) in September 2024?

The climate in San Marcos during September can be summarized as warm, humid and very wet.

September is in the fall / autumn in San Marcos and is typically the 6th coldest month of the year. Daytime maximum temperatures average around a muggy 26°C (78°F), whilst at night 19°C (66°F) is normal.

San Marcos weather averages (imperial / metric)
Daytime temperature 25.8°C 78.4°F
Nightly temperature 18.8°C 65.8°F
Average temperature 22.3°C 72.1°F
Daily sunshine 6.1 hrs
Avg rainfall 411 mm 16.2 ins
Rainy days 23 days
Sea temperature 28.6°C 83.5°F
Humidity 85%
Windspeed 9.7kph 6 mph

On average September is the 2nd wettest month of the year in San Marcos with around 411mm 16.2 inches of rain making it a very wet time to visit. This rainfall is typically spread over 23 days, although this may vary considerably.

On the flip side this corresponds to an average of 6.1 hours of sunshine per day.

September temperatures in San Marcos

San Marcos average temperature in September

September rainfall

San Marcos average rain in September

September hourly sunshine

San Marcos average rain in September

The data used in these monthly averages covers a period of over 100 years right up until last year. As such they are a valid prediction of what to expect for the weather in San Marcos in September 2024.

Other monthly averages

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San Marcos weather stats

San Marcos weather statistics
Hottest month: April 27.4°C 81.3°F
Driest month: January 6mm 0.2ins
Sunniest month: March 8.1hrs
Coldest month: December 25.4°C 77.7°F
Wettest month: October 442mm 17.4ins
Map showing location of San Marcos (9.6601, -84.02026) San Marcos map pin © Google

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