If you’re looking forward to lots of outings with your partner, take a look at these details about year-round temperatures in Yiwu: The hottest months are usually August and July, with an average temperature of 26°C, while the coldest months are January and December, with an average of 8°C. The rainiest months in Yiwu are June, July, May and August, with each month seeing an average of 248 mm of rainfall.