Abstract: Based on hourly observations of wind field at Nanyue Mountain station between April and June from 2005 to 2013, conventionalsounding data, rainfall data from automatic weather station and 2.5 °×2.5° global reanalysis data from NCEP/NCAR, we analyze the representativenessof data collected at the Nanyue station to the atmospheric general circulation field in the lower troposphere and the indicativefunction of the evolution characteristics of wind field at the station to heavy rain over Northern Jiangxi in flood season. Main results are as follows.(1) The most significant correlation (correlation coefficient 0.72-0.78) between daily wind at the Nanyue station and daily 850 hPa windfield from NCEP, locates around Nanyue Mountain, in which the wind has a good indicative function to the local wind field at 850 hPa. Theaverage correlation coefficient (0.75) is higher between wind at the station and 850 hPa wind field from NCEP than that (0.68) between wind atthe station and 925 hPa wind field from NCEP, which proves that wind at the station is much closer to local wind field at 850 hPa. (2) Thecloser (farther) the distance between a sounding station and the Nanyue station is, the better (worse) the correlation of various meteorologicalelements between them is, which further confirms the above conclusions. (3) In flood season, when there is southwest wind at Nanyue stationand corresponding shear index, the probability of heavy rain over Northern Jiangxi within 24 h reaches 89.8%. When the above criteria aremet and after the wind at the Nanyue station changes from other direction (weak southwest wind) to southwest direction (strong southwestwind) from 20:00 BT of the current day to 08:00 BT next day, we can forecast heavy rain over Northern Jiangxi within 4-18 h (10 hours on average).After the occurrence of heavy rain over Northern Jiangxi, the severe precipitation area starts to shift southwards and moves eastwardsafter 1-3 h when wind at the Nanyue station changes from southwest direction sustained to northerly direction. Then, it shifts southwards ormoves eastwards out of Northern Jiangxi within 6-17 h (10.5 hours on average).