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The analysis of potential evaporation and dry/wet indexes is meaningful to the utilization of water resources and the prevention of agricultural droughts. By using the 34year data from the Fuzhou weather station, the distribution characteristics of potential evaporation and humid indexes are analyzed. The results show that: (1) from 1980, the potential evaporation has been increasing; the year of 1991 was the climate jump point, with the anomaly being negative before it and positive after it; (2) the humid index decreased obviously because of the decrease of precipitation and the increase of potential evaporation, so the natural rain cannot meet the water demands of crops and droughts occurred frequently, and the annual mean humid index had no clear climate jump; (3) according to the humid indexes, the autumn was the driest season, then the summer and winter.