 The Missouri 's drainage basin has highly variable weather and rainfall patterns , Overall , the watershed is defined by a Continental climate with warm , wet summers and harsh , cold winters . Most of the watershed receives an average of 8 to 10 inches ( 200 to 250 mm ) of precipitation each year . However , the westernmost portions of the basin in the Rockies as well as southeastern regions in Missouri may receive as much as 40 inches ( 1 @,@ 000 mm ) . The vast majority of precipitation occurs in winter , although the upper basin is known for short @-@ lived but intense summer thunderstorms such as the one which produced the 1972 Black Hills flood through Rapid City , South Dakota . Winter temperatures in Montana , Wyoming and Colorado may drop as low as − 60 ° F ( − 51 ° C ) , while summer highs in Kansas and Missouri have reached 120 ° F ( 49 ° C ) at times . 
 The Missouri <a href='null_genetive' title='1'><mark>'s</mark></a>drainage basin <a href='got' title='2'><mark>has</mark></a> highly variable weather and rainfall patterns , Overall , the watershed is defined by a Continental climate with warm , wet summers and harsh , cold winters . Most of the watershed <a href='uninflect' title='3'><mark>receives</mark></a> an average of 8 to 10 inches ( 200 to 250 mm ) of precipitation each year . However , the westernmost portions of the basin in the Rockies as well as southeastern regions in Missouri may receive as much as 40 inches ( 1 @,@ 000 mm ) . The vast majority of precipitation <a href='uninflect' title='4'><mark>occurs</mark></a> in winter , although the upper basin is known for short @-@ lived but intense summer thunderstorms such as the one which produced the 1972 Black Hills flood through Rapid City , South Dakota . Winter temperatures in Montana , Wyoming and Colorado may drop as low as − 60 ° F ( − 51 ° C ) , while summer highs in Kansas and Missouri <a href='been_done' title='5'><mark>have</mark></a> reached 120 ° F ( 49 ° C ) at times . 
The Missouri  drainage basin got highly variable weather and rainfall patterns , Overall , da watershed is defined by a Continental climate wid warm , wet summers and harsh , cold winters . Most of tdawatershed receive an average of 8 to 10 inches ( 200 to 250 mm ) of precipitation each year . However , thdaesternmost portions of the basin in thedackies as well as southeastern regions in Missouri may receive as much as 40 inches ( 1 @,@ 000 mm ) . The vast majority of precipitation occur in winter , although the upper basin is known for short @-@ lived but intense summer thunderstorms such as the da which produced the 1972 Black Hills flood through Rapid City , South Dakota . Winter temperatures in Montana , Wyoming and Colorado may drop as low as − 60 ° F ( − 51 ° C ) , while summer highs in Kansas and Missouri done reached 120 ° F ( 49 ° C ) at times .