In terms of precipitation, rainfall in Siem Reap ranges from 0.0 - 10.2 inches per month. September is typically the wettest month, when rainfall can reach 10.2 in. January is typically the driest time to visit Siem Reap when rainfall is around 0.0 in.
If weather is an important factor for your trip to Siem Reap, use this chart to help with planning. For those seeking warmer temperatures, April is the ideal time of year to visit, when temperatures reach an average of 84.2 F. Travelers looking to avoid the cold should look outside of December, when temperatures are typically at their lowest (around 75.2 F).