 The 2003 Pacific typhoon season was a slightly below average yearlong period of tropical cyclogenesis exhibiting the development of 31 tropical depressions , of which 21 became named storms ; of those , 14 became typhoons . Though every month with the exception of February and March featured tropical activity , most storms developed from May through October . During the season , tropical cyclones affected the Philippines , Japan , China , the Korean Peninsula , Indochina , and various islands in the western Pacific . 
 The 2003 Pacific typhoon season was a slightly below average yearlong period of tropical cyclogenesis exhibiting the development of 31 tropical depressions , of which 21 became named storms ; of those , 14 became typhoons . Though every month with the exception of February and March<a href='been_done' title='1'><mark></mark></a> featured tropical activity , most storms developed from May through October . During the season , tropical cyclones affected the Philippines , Japan , China , the Korean Peninsula , Indochina , and various islands in the western Pacific . 
The 2003 Pacific typhoon season was a slightly below average yearlong period of tropical cyclogenesis exhibiting da development of 31 tropical depressions , of which 21 became named storms ; of those , 14 became typhoons . Though every month wit the exception of February and March done featured tropical activity , most storms developed from May thru October . durin the season , tropical cyclones affected the Philippines , Japan , China , tdaKorean Peninsula , Indochina , and various islands in thdaestern Pacific .