During the Meiyu period in June and July of 1998, intensified field observations have been carried outfor the project "Huaihe River Basin Energy and Water Cycle Experiment (HUBEX)". For studying Meiyufront and its precipitation in Huaihe River basin, the present paper has performed analysis on the middleand lower level wind ficlds in the troposphere by using the radar data obtained from the two Doppler radarslocated at Fengtai district and Shouxian County.From June 29 to July 3 in 1998. the continuous heavy precipitation occurred in Huaihe River basinaround Meiyu front. The precipitation process on July 2 occurred within the observation range of the twoDoppler radar in Fengtai district and Shouxian County. The maximum rainfall of the Meiyu front was over100 mm in 24h, so it can be regarded as a typical mesoscale heavy precipitation process related to Meiyufront.Based on the wind field retrieved from the dual Doppler radar, we find that there are mesor-γ scale vertical circulations in the vertical cross-section perpendicular to Meiyu front, the strong upward motion ofwhich corresponds to the position of the heavy rainfall area. Furthermore, other results obtained by thisstudy are identical with the results by analyzing the conventional synoptic data years ago. For example: inthe vicinity of 3 km level height ahead of Meiyu front there exists a southwest low-level jet; the rainstormcaused by Meiyu front mainly occurs at the left side of the southwest low-level jet, and the Meiyu frontcauses the intensification of the low-level convergence in front of it.
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