For dirty superconducting/ferromagnetic superlattices, we study theoretically the temperature dependence of the upper critical fields parallel ${H}_{c2\ensuremath{\Vert}},$ and perpendicular ${H}_{c2\ensuremath{\perp}},$ to the layers. Numerical results show that very thin ferromagnetic layers do not decouple the neighboring superconducting layers. We also study the superconducting transition temperature of the superlattices as a function of the thickness of the ferromagnetic layers. This shows nonmonotonic behavior under appropriate conditions which is due to the $\ensuremath{\pi}$-phase state which is peculiar to these systems. Additionally, we calculate the spatial variation of the pair function in order to interpret quantitatively the above results.