Atenas Monthly Rainfall & Precipitation
This page shows both the average monthly rainfall and the number of rainy days in Atenas, Alajuela, Costa Rica. These values are calculated using 30 years of data (1990–2020) to ensure accuracy. Now, let's explore all the details to give you a full picture.
Atenas has a notably wet climate with abundant precipitation, recording 3182 mm (125 in) of rainfall per year. It does, however, have a distinct dry and rainy season during certain months. Have a look at our detailed charts below to see how precipitation varies throughout the year.
Monthly Precipitation Levels
The average number of days each month with precipitation (> 0.2 mm (0.01 in))
The seasons in Atenas, bring significant changes in precipitation. The wettest month, October, receives heavy rainfall, with an average of 497 mm (20 in) of precipitation. This rainfall is distributed across 22 rainy days.
In contrast, the driest month, February, experiences much less rainfall, totaling 31 mm (1.2 in) over 8 rainy days. These distinct seasonal differences provide diverse experiences throughout the year.October, the wettest month, has a maximum daytime temperature of 26°C (79°F). The city receives 161 hours of sunshine in this period. During the driest month February you can expect a temperature of 29°C (84°F). For more detailed insights into the city's temperatures, visit our Atenas Temperature page.
Daily Historical Precipitation
42-year average (1976-2025)
Average daily rainfall for each day of the month based on long-term records.
Average precipitation in June
Explore Atenas's Historical Precipitation: 1976-2026
Browse day-by-day precipitation records for Atenas spanning 51 years. Select any month and year to see actual rainfall and snowfall recorded on each day.
Annual Rainfall in Costa Rica: City Comparison
The map below shows the annual precipitation across Costa Rica. You can also select the different months in case you are interested in a specific month.
heavy rainfall
high
moderate
low
almost none
Atenas vs World: Rainfall Compared
Atenas's average annual precipitation is 3182 mm (125 in). Let's compare this to some popular worldwide tourist destinations:
In Lisbon, Portugal, the average annual precipitation is 774 mm (30 in), characterized by wet winters and dry summers typical of the Mediterranean climate.
Osaka, Japan, experiences 1507 mm (59 in) of rainfall annually, spread across the year with wetter summers.
In Brisbane, Australia, the annual precipitation is 979 mm (39 in), making it wetter than Sydney.
Mumbai, India, experiences a tropical monsoon climate with 1860 mm (73 in) of annual rainfall, with the majority of precipitation happening during the monsoon season from June to September.
Precipitation amounts are measured using specific gauges installed at weather stations, collecting both rain and snow and any other type of precipitation. Rainfall is measured directly in millimeters, while that from snow and ice is obtained by melting it. Automated systems often incorporate heaters to make this easier.
Information from these stations is transmitted via Wi-Fi, satellite, GPS, or telephone connections to central monitoring networks. This information is immediately updated and integrated into weather models and forecasts.
Precipitation has a very strong role in determining the local climate and ecosystem:
- Changing Rainfall Patterns: Global warming causes drastic changes in the patterns of rainfall. Some areas have been experiencing increased frequency and intensity of rainfall, while other areas experience longer dry spells or even droughts.
- Local Impacts: Many regions are experiencing heavier rainfall in the winter months and drier, hotter summers. This affects agriculture, water resources, and ecosystems.
- Mawsynram in India is noted as being the wettest place on earth, with over 11 meters (36 feet) of rain falling every year.
- In contrast, Antofagasta in Chile is among the driest places on the planet, getting less than 0.1mm (0.004 inches) per year, with some years recording virtually no rainfall.
- Nearly 1,650 thunderstorm cells are estimated over the planet at any given time.
For more detailed information about Atenas's weather, including sunshine hours, humidity levels, and temperature data, visit our Atenas Climate page.
