In this article, we attempt to quantify the variability of water pressure head in response to temporally correlated fluctuations in infiltration rate in partially saturated heterogeneous formations. This study concentrates on the unsaturated case of predominantly vertical movement of moisture. A closed-form solution is developed to analyze the impacts of the temporal correlation scale of infiltration fluctuations and the spatial correlation scale of log-saturated hydraulic conductivity () field on the variability in water pressure head. Our result indicates that the temporal correlation scale of infiltration process or the spatial correlation scale of field takes a role in increasing the variability in the pressure head.