September weather forecast and climate
San José, Costa Rica

An aerial skyscape of San José, Costa Rica in the evening sun
An aerial skyscape of San José, Costa Rica in the evening sun
September, the first month of the autumn, in San José, is still a warm month, with average temperature ranging between max. 26.9°C (80.4°F) and min. 18.2°C (64.8°F).

Temperature

In San José, Costa Rica, the average high-temperature is 26.9°C (80.4°F), and the average low-temperature is 18.2°C (64.8°F).

Rainfall

The month with the most rainfall is September when the rain falls for 18 days and typically aggregates up to 355.1mm (14") of precipitation.

Daylight

The average length of the day in September is 12.2h.

Sunshine

The average sunshine in San José, Costa Rica, is 4.9h.

UV index

February through October, with an average maximum UV index of 12, are months with the highest UV index. A UV Index of 11, and more, symbolizes an extreme health hazard from unprotected exposure to the Sun's UV rays for ordinary individuals.
The average daily UV index of 12 transform into the following instructions:
Take all required precautions, as unprotected skin and eyes can burn in minutes. The Sun's UV radiation is most powerful between 10 a.m. and 4 p.m. To the extent possible, limit exposure to the direct sun during these hours. On bright days sunglasses that block both UVA and UVB rays should be worn. A hat with a wide brim is extremely helpful, as it can prevent roughly 50% of UV radiation from reaching the eyes.

What is the temperature in September in San José?

In September, in San José, Costa Rica, the average high-temperature is 26.9°C (80.4°F), and the average low-temperature is 18.2°C (64.8°F).

How many days does it rain in September in San José?

In San José, Costa Rica, in September, it is raining for 18 days, with typically 355.1mm (14") of accumulated precipitation.

What is the wettest month in San José?

September is the month with the most rainfall in San José, Costa Rica. Rain falls for 18 days and accumulates 355.1mm (14") of precipitation.

How many hours of daylight does San José have in September?

In San José, Costa Rica, the average length of the day in September is 12.2h.

How many hours of sunshine does San José have in September?

In San José, Costa Rica, the average sunshine in September is 4.9h.

When is the highest UV index in San José?

Months with the highest UV index in San José, Costa Rica, are February through October, with an average maximum UV index of 12.

How high is the UV index in September in San José?

In San José, Costa Rica, the average daily maximum UV index in September is 12. A UV Index estimate of 11, and higher, represents an excessive health risk from the exposure to the Sun's UV radiation.
Average temperature in September - San José, Costa Rica
  • Average high temperature in September: 26.9°C

The warmest month (with the highest average high temperature) is April (28.4°C).
The month with the lowest average high temperature is December (25.9°C).

  • Average low temperature in September: 18.2°C

Months with the highest average low temperature are May and July (19°C).
The coldest month (with the lowest average low temperature) is January (17.8°C).

Average rainfall in September - San José, Costa Rica
  • Average rainfall in September: 355.1mm

The wettest month (with the highest rainfall) is September (355.1mm).
The driest month (with the lowest rainfall) is January (6.3mm).

Average rainfall days in September - San José, Costa Rica
  • Average rainfall days in September: 18 days

The month with the highest number of rainy days is September (18 days).
Months with the lowest number of rainy days are January and February (1 days).

Average daylight in September / Average sunshine in September - San José, Costa Rica
  • Average daylight in September: 12.2h

The month with the longest days is June (Average daylight: 12.7h).
Months with shortest days are January and December (Average daylight: 11.6h).

  • Average sunshine in September: 4.9h

The month with most sunshine is February (Average sunshine: 9.5h).
The month with least sunshine is June (Average sunshine: 4.8h).

Average UV index in September - San José, Costa Rica
  • Average UV index in September: 12

Months with the highest UV index are February, March, April, May, June, July, August, September and October (UV index 12).
The month with the lowest UV index is December (UV index 10).

deutscheenglishespañolрусский中文