Abstract: Based on the soil moisture and meteorological data of 2007-2008 in Jinhua City,changes of the soil moisture were analyzed by the grey correlation degree method.The soil moisture and related meteorological factors were analyzed with the method of grey correlation degree analysis.The key meteorological factors were ascertained and the soil moisture forecast model was built and validated.The results showed that the soil moisture content was high and stable in winter and spring in Jinhua City,while it was low with larger variation in summer and autumn.The difference between precipitation by 5mm and evaporation was the key meteorological factor affecting soil moisture content.With the soil moisture prediction model based on the key meteorological factor,the soil moisture in summer of 2008 was predicted.The average forecast error for soil layer 0-10cm,10-20cm and 20-30cm was 15.75%,6.89% and 8.21% respectively.The results for the soil moisture content forecasted by this model revealed the developing tendency of the drought in Jinhua City.

Key words: Soil moisture forecast, Soil moisture forecast, Meteorological factor, Grey correlation degree