Climate Overview
The climate in Siem Reap is hot. The average annual temperature is 28°C and approximately 1477mm of precipitation falls per year. September is the wettest month, receiving around 285mm of rainfall. Siem Reap is in the Northern Hemisphere. Summer begins at the end of June and lasts through September. The summer months are: April, March, May. The coldest months are January, December, February, when temperatures can drop to 21°C.
Temperature
Siem Reap sees moderate temperature variation throughout the year, ranging from 21°C to 36°C. April is the hottest month, with daytime highs reaching 36°C and an average of 30°C. January is the coolest month, with minimum temperatures around 21°C and an average of 26°C. Daily temperature variation is modest, with an average difference of 8°C between highs and lows. The sharpest temperature change occurs between February and March, with a 2°C shift in average temperatures.
Precipitation
Siem Reap is a fairly wet location, receiving approximately 1477mm of precipitation annually, which averages out to around 123mm per month. The wettest month is September, averaging 285mm of rainfall. October and July also tend to see above-average precipitation. The driest month is February, with just 13mm. That's 272mm less than September, the wettest month. Rainfall is heavily concentrated in certain months, creating a distinct wet and dry season. Visitors should plan around these patterns, as the difference between peak and low months is dramatic.
Wind
Siem Reap is relatively calm, with an average annual wind speed of 11km/h. For context, sustained winds below 12km/h are generally light, while anything above 25km/h is considered strong. The windiest month is July, averaging 14km/h, though still comfortable for most outdoor activities. The calmest conditions occur in October, with average winds dropping to 9km/h, making it an ideal period for wind-sensitive activities. There is moderate seasonal variation in wind speed, with a 5km/h gap between the calmest and windiest months.
Seasons
89 days until Summer
It is currently spring in Siem Reap, which began on March 20, 2026. Siem Reap is in the Northern Hemisphere, where spring begins in March, summer in June, autumn in September, and winter in December. The warmest period peaks in April at around 36°C, while the coldest stretch bottoms out in January near 21°C. Summer is next, beginning on June 21, 2026 — 89 days from now.
Spring
Temperatures range from 25 to 36°C. Precipitation is moderate at around 264mm for the season, averaging 88mm per month. Winds are generally light, averaging 10km/h. An umbrella or waterproof jacket is advisable as spring showers are frequent.
Summer
Temperatures range from 26 to 34°C. Rainfall is heavy, totalling around 579mm across the season with a monthly average of 193mm. Winds are generally light, averaging 13km/h. Light, breathable clothing is ideal — perfect conditions for outdoor activities.
Autumn
Temperatures range from 23 to 32°C. Rainfall is heavy, totalling around 583mm across the season with a monthly average of 194mm. Winds are generally light, averaging 10km/h. A waterproof jacket and sturdy footwear are recommended as rain becomes more frequent.
Winter
Temperatures range from 21 to 33°C. Rainfall is relatively light, with around 51mm over the season and a monthly average of 17mm. Winds are generally light, averaging 11km/h. A light jacket or sweater is usually sufficient, though cooler evenings may call for an extra layer.
Monthly Climate Data
The table below shows monthly climate averages for Siem Reap based on historical weather data. Min and max temperatures represent typical overnight lows and afternoon highs for each month, shown in degrees Celsius (°C). Precipitation is measured in millimetres (mm) and indicates the average total rainfall per month. Wind speed is the average sustained speed in kilometres per hour (km/h). All values are based on averages from over 10 years of historical weather data. The current month is highlighted for quick reference.
