我國東南沿海地區冷鋒之移動速度及其降水預報之研究

陳正改

中央氣象局

ABSTRACT

　　In this study, General J. J. George’s method is adapted for forecasting the movement of cold fronts along the coast of Southeast China.
　　As for the movement of cold fronts parameters of prediction are based upon the current 850mb charts according to the following criteria:
　　(1) The height difference between the reference point on the front and the points 600 miles east and west of the front .at 850mb chart is measured and a correction is given according to latitude.
　　(2) The temperature gradient at 850mb is measured from the reference point on the front to the point 600 miles north ward.
　　Concerning of precipitation forecasting, the prediction parameters are developed from the moisture pattern and height-change field at 850mb. The moisture parameter is defined as a tongue of moist air at 850mb in which the dew points are from 0°C to 10°C for light rain, and 10°C or higher for thunderstorms. The height-change fields within 24-hour are obtained by subreacting the previous 850mb chart from the current one with an interval of 24 hours.