Yiwu Weather In General:
Yiwu has a weather similar to London, Paris, Geneva, and New York. Very much like Las Vegas and Tokyo.
Warm spring, hot summer, cool autumn, and cold winter.
Spring: Mar.-Apr. Temperature: 10C/50H-25C/77H. If you go to Yiwu in this time, sweaters, suits and shirts would be enough.
Summer: Jun.-Aug. Temperature: 25C/77H-35C/95H. It rains a lot in June, day in and day out. Shorts, thin shirts, skirts would be ideal. Sun glasses, sun-creams would be a plus.
Autumn: Sep.-Nov. Temperature: 10C/50H-25C/77H. Any clothes you wear with this temperature.
Winter: Dec.-Feb. Temperature: 0C/32H-10C/50H. Winter clothes like thick coat, warm socks, gloves… anything that can keep you from cold.

Accurate Yiwu Weather Now :
More useful links:
1. Yiwu Weather Forecasts on Yahoo! Weather: Yiwu Weather Forecasts on Yahoo! Weather
2. Weather in Yiwu China on MSN Weather: Weather in Yiwu on MSN Weather
3. Yiwu Weather forecast on AOL weather: Yiwu Weather forecast on AOL weather