Ja-Ela Monthly Rainfall & Precipitation
This page shows both the average monthly rainfall and the number of rainy days in Ja-Ela, Gampaha District, Sri Lanka. This average is based on long-term data collected between 1990 and 2020. Now, let's explore all the details to give you a full picture.
Ja-Ela is known for its substantial rainfall, with annual precipitation reaching 2505 mm (99 in). While the overall climate is wet, there are notable seasonal patterns that create interesting contrasts, as demonstrated in our graph below.
Monthly Rainfall & Rainy Days
Monthly Precipitation Levels
The average number of days each month with precipitation (> 0.2 mm (0.01 in))
Ja-Ela can be quite wet during October, receiving approximately 352 mm (14 in) of precipitation over 16 rainy days.
In contrast January, experiences much drier conditions, with 60 mm (2.4 in) of rainfall, spread across 5 rainy days.
October, the wettest month, has a maximum daytime temperature of 30°C (86°F). The city receives 202 hours of sunshine in this period. During the driest month January you can expect a temperature of 32°C (90°F). For more detailed insights into the city's temperatures, visit our Ja-Ela Temperature page.
Annual Rainfall in Sri Lanka: City Comparison
The map below shows the annual precipitation across Sri Lanka. You can also select the different months in case you are interested in a specific month.
Ja-Ela vs World: Rainfall Compared
Ja-Ela's average annual precipitation is 2505 mm (99 in). Let's compare this to some popular worldwide tourist destinations:
Boston, USA, experiences 1238 mm (49 in) of annual precipitation, including significant snowfall during the winter.
Meanwhile, Buenos Aires, Argentina, enjoys a humid subtropical climate with 1000 mm (39 in) of annual rainfall, mostly in the summer.
In Tokyo, Japan, the average annual precipitation is 1528 mm (60 in), with significant summer rains due to typhoon season.
Bangkok, Thailand, experiences a tropical monsoon climate with 1668 mm (66 in) of annual rainfall, with the heaviest precipitation occurring during September and October.
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.
- The U.S. has a significant number of thunderstorms every year, with over 14.6 million taking place across the world annually.
- Approximately 70% of lightning bolts strike land rather than oceans.
- A storm named John was the longest-lasting Pacific tropical storm, continuing for 31 days. As it crossed the dateline twice, it changed status from a hurricane to a typhoon and back to a hurricane.
For more detailed information about Ja-Ela's weather, including sunshine hours, humidity levels, and temperature data, visit our Ja-Ela Climate page.
Ja-Ela Weather by Month
Pick a month to see the average temperature, rainfall and sunshine in Ja-Ela - and find the best time to visit.
Ja-Ela 3-Day Forecast
Temperature Rainfall Sunshine Humidity Wind Speed Water Temp
See the full Ja-Ela climate overview or explore weather in Sri Lanka.
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