Koh Samet Monthly Rainfall & Precipitation
This page shows both the average monthly rainfall and the number of rainy days in Koh Samet, Rayong Province, Thailand. The figures are based on a 30-year period (1990–2020) to provide a reliable average. Let's now guide you through the details for a complete overview.
Koh Samet has a relatively rainy climate with high precipitation levels, averaging 1960 mm (77 in) of rainfall annually. Despite the high annual total, it does experience a distinct dry and rainy season during certain months. Examine our detailed charts below to understand these seasonal patterns.
Monthly Precipitation Levels
The average number of days each month with precipitation (> 0.2 mm (0.01 in))
The seasons in Koh Samet, bring significant changes in precipitation. The wettest month, September, receives heavy rainfall, with an average of 322 mm (13 in) of precipitation. This rainfall is distributed across 19 rainy days.
In contrast, the driest month, December, experiences much less rainfall, totaling 16 mm (0.6 in) over a single rainy day. These distinct seasonal differences provide diverse experiences throughout the year.September, the wettest month, has a maximum daytime temperature of 30°C (86°F). The city receives 110 hours of sunshine in this period. During the driest month December you can expect a temperature of 31°C (88°F). For more detailed insights into the city's temperatures, visit our Koh Samet Temperature page.
Daily Historical Precipitation
50-year average (1976-2025)
Average daily rainfall for each day of the month based on long-term records.
Average precipitation in June
Explore Koh Samet's Historical Precipitation: 1976-2026
Browse day-by-day precipitation records for Koh Samet spanning 51 years. Select any month and year to see actual rainfall and snowfall recorded on each day.
Annual Rainfall in Thailand: City Comparison
The map below shows the annual precipitation across Thailand. You can also select the different months in case you are interested in a specific month.
heavy rainfall
high
moderate
low
almost none
Koh Samet vs World: Rainfall Compared
Koh Samet's average annual precipitation is 1960 mm (77 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.
Meanwhile, Buenos Aires, Argentina, enjoys a humid subtropical climate with 1000 mm (39 in) of annual rainfall, mostly in the summer.
In Brisbane, Australia, the annual precipitation is 979 mm (39 in), making it wetter than Sydney.
Kuala Lumpur, Malaysia, receives 2529 mm (100 in) of annual rainfall, characteristic of its equatorial tropical rainforest climate, with consistent rainfall throughout the year and peak months during March and November.
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.
- 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 Koh Samet's weather, including sunshine hours, humidity levels, and temperature data, visit our Koh Samet Climate page.
