Contents
- Weather in September
- Frequently asked questions
- Average temperature in September
- Average pressure in September
- Average wind speed in September
- Average humidity in September
- Average rainfall in September
- Average rainfall days in September
- Average daylight in September
- Average sunshine in September
- Average sunshine days in September
- Average UV index in September
- Average cloud cover in September
- Average visibility in September
September
Weather in September
Temperature
The commencement of September notes an average high-temperature of a still moderately hot 23°C (73.4°F), exhibiting little difference from the previous month. The nighttime temperature dips to a comfortable 16.4°C (61.5°F) on average during September.Humidity
September and October, with an average relative humidity of 91%, are the most humid months.Rainfall
In September, the rain falls for 29.5 days. Throughout September, 344mm (13.54") of precipitation is accumulated. In Alajuelita, during the entire year, the rain falls for 287.8 days and collects up to 2585mm (101.77") of precipitation.Daylight
In Alajuelita, the average length of the day in September is 12h and 11min.On the first day of September, sunrise is at 05:27 and sunset at 17:45. On the last day of the month, sunrise is at 05:24 and sunset at 17:27 CST.
Sunshine
In September, the average sunshine in Alajuelita is 6.5h.UV index
January through December, with an average maximum UV index of 5, are months with the highest UV index. The months with the lowest UV index are January through December, with an average maximum UV index of 5. A UV Index value of 3 to 5 symbolizes a moderate threat to health from exposure to the Sun's UV rays for the average person.Note: In September, a daily maximum UV index of 5 leads to the following instructions:
Guard yourself - Avoiding sunburn is suggested. To avoid the Sun's strongest rays, limit exposure around the mid-day period. Safeguard your eyes, ears, and face from sun rays with the aid of a wide-brim hat.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the temperature in September?
What is the most humid month?
What is the average humidity in September?
How much does it rain in September?
What is the average length of the day in September?
When is the sunrise / sunset in September?
How long on average sun shines in September?
When is the highest UV index?
What are the months with the lowest UV index?
What is the UV index intensity in September?
Average temperature in September
Alajuelita, Costa Rica
- Average high temperature in September: 23°C
The warmest month (with the highest average high temperature) is April (26°C).
The month with the lowest average high temperature is October (22.4°C).
- Average low temperature in September: 16.4°C
The month with the highest average low temperature is June (17°C).
The coldest month (with the lowest average low temperature) is January (13.8°C).
Average pressure in September
Alajuelita, Costa Rica
- Average pressure in September: 1011.1mbar
The month with the highest atmospheric pressure is January (1012.3mbar).
The month with the lowest atmospheric pressure is October (1010.8mbar).
Average wind speed in September
Alajuelita, Costa Rica
- Average wind speed in September: 4.3km/h
The windiest month (with the highest average wind speed) is February (10.7km/h).
The calmest month (with the lowest average wind speed) is September (4.3km/h).
Average humidity in September
Alajuelita, Costa Rica
- Average humidity in September: 91%
The months with the highest relative humidity are September and October (91%).
The months with the lowest relative humidity are February and March (75%).
Average rainfall in September
Alajuelita, Costa Rica
- Average rainfall in September: 344mm
The wettest month (with the highest rainfall) is October (438mm).
The driest month (with the least rainfall) is February (26mm).
Average rainfall days in September
Alajuelita, Costa Rica
- Average rainfall days in September: 29.5 days
The month with the highest number of rainy days is October (30.5 days).
The month with the least rainy days is February (12.2 days).
Average daylight in September /
Average sunshine in September
Alajuelita, Costa Rica
- Average daylight in September: 12h and 1min
The month with the longest days is June (Average daylight: 12h and 42min).
The month with the shortest days is December (Average daylight: 11h and 36min).
- Average sunshine in September: 6h and 3min
The month with the most sunshine is February (Average sunshine: 9h and 12min).
The month with the least sunshine is October (Average sunshine: 5h and 48min).
Average sunshine days in September
Alajuelita, Costa Rica
- Average sunshine days in September: 0.1 days
The month with the most sunshine days is March (13.5 days).
The month with the least sunshine days is September (0.1 days).
Average UV index in September
Alajuelita, Costa Rica
- Average UV index in September: 5
The months with the highest UV index are January, February, March, April, May, June, July, August, September, October, November and December (UV index 5).
The months with the lowest UV index are January, February, March, April, May, June, July, August, September, October, November and December (UV index 5).
Average cloud cover in September
Alajuelita, Costa Rica
- Average cloud cover in September: 65
The month with the most cloud cover is October (Cloud cover 68).
The month with the least cloud cover is February (Cloud cover 30).
Average visibility in September
Alajuelita, Costa Rica
- Average visibility in September: 6km
The months with the highest visibility are January, February and March (9km).
The months with the lowest visibility are August, September, October and November (6km).
