The probabilities of drought and flood emergence are roughly equal, and the probability of sub-flood is lager than the sub-drought significantly and multiyear return period is shorter than the latter.

• 六安市汛期干旱和雨涝年份出现的概率大体相当，偏涝年份出现的概率明显大于偏旱年份，重现期短于后者。