Abstract: The high frequency of extreme precipitation events resulted from global warming strongly influences the crop growth and the development of economy and society.Using the daily precipitation data from 16 stations in Handan region from May to September during 1974-2015,the climatic characteristics of the rainy days with different ranks were analyzed,and the relationships between the number of rainy days with different ranks and the corresponding amount of precipitation were discussed as well.The results show that there is a spatial difference in the rainy days with different ranks.In the western mountainous regions,the number of light to moderate rainy days are higher,and the number of heavy to storm rainy days are less,whereas the situations in the eastern plain are opposite.With the increase of precipitation ranks,the number of rainy days reduces rapidly.In Handan,the numbers of total,light,and storm rainy days show an obvious decreasing trend,while those of moderate and heavy rainy days show an obvious increasing trend,especially in Fengfeng mining area.Since entering into the 21st century,the number of moderate rainy days has increased significantly.The variation characteristics between the number of rainy days with different ranks and the corresponding precipitation time are consistent.The number of total rainy days is mainly due to the contributions of the light,moderate and heavy rainy days,especially due to the light ones.The total amount of precipitation chiefly comes from the storm ones.During the recent 42 years,with the increase of precipitation ranks,the correlations between the total amount of precipitation and the amount of precipitation at different ranks rapidly increase.The correlation of the amount of total precipitation with that of the storm is the highest,and with that of light precipitation is the lowest.

Key words: Rainy days, Precipitation, Climatic characteristics, Correlation