You'll likely spend much of your trip indoors, but if you want to see more of the area, taking a look at local weather data can help you. The hottest months are usually July and August, with an average temperature of 20°C, while the coldest months are January and December, with an average of -6°C. The rainiest months in Dandong are August, July, June and May, with each month seeing an average of 213 mm of rainfall.