If you’re hoping to get lost in the rain on your romantic getaway, take a look at these details about year-round temperatures in Guiyang: The hottest months are usually August and July, with an average temperature of 22°C, while the coldest months are January and December, with an average of 8°C. The rainiest months in Guiyang are June, May, April and July, with each month seeing an average of 203 mm of rainfall.