Mississippi River Basin Rainfall in Average Year

Rainfall and snow melt are key inputs to the Mississippi river system. Maintaining water levels is vital not only for transport but also for the 260 fish species that call the Mississippi home. For example strong drought conditions can lower river levels to a point that severely impact on the ecology and can halt transport on the river, as occurred in 1988 - see Drought Affects Mississippi River Traffic.

Rainfall maps for the Mississippi river basin show south eastern areas receive higher rainfall than the north west. However looking at a time series of rainfall for the Mississippi basin shows variability over the yearly seasonal cycle. This variability is seen as patchiness of rainfall within the river basin area with the north west region receiving lower rainfall than the south east corner particularly for the months of Nov to Feb. The patchy nature of the rainfall distribution as well as the amount of rainfall makes the Mississippi river a challenge for its many users.

Average Total Rainfall (mm/yr)

Bargraph referencing the colours on the rainfall maps.

Other Mississippi Maps

Mississippi Rainfall Maps