In this paper, we consider a time-fractional coupled KdV equations describing the interaction of equatorial and midlatitude Rossby waves. From the application of Lie group analysis, the governing system of fractional partial differential equations (FPDEs) is reduced to a system of fractional ordinary differential equations (FODEs). Further, we construct the group-invariant solution as well as the power series solution for the given coupled equations. Next, the evolutionary behavior of the waves under the influence of the fractional order derivative [Formula: see text] is studied graphically through the group-invariant solution. Finally, the conservation laws for the given system of FPDEs are obtained.