The characteristics of the general circulation at 500 hPa over the middle and lower latitudes of Asia during June were discussed with relation to the wet/dry Meiyu season in the northern part of Zhejiang province, thus leading to the long-range forecasting of the wet/dry Meiyu season by using the characteristic values of the general circulation in March. It is found that the wet Meiyu season is characterized by "X" and"V" patterns of the is allohypse field at 500 hPa during June, while thedry Meiyu season by "M" pattern, showing a sharp contrast. Good resultshave been proved by using the characteristic values of the March circulation to forecast the wet/dry Meiyu season.