Natural variability in the annual flow of the Nile River has been the subject of great interest to the civilizations that have historically occupied the banks of that river. Here we report results from analysis on two extensive data sets describing sea surface temperature of the Pacific Ocean, and the flow of water in the Nile River. The analysis suggests that 25% of the natural variability in the annual flow of the Nile is associated with El Niño oscillations. A procedure is developed for using this observed correlation to improve the predictability of the Nile flood. A simple hypothesis is presented to explain physically the occurrence of the Hurst phenomenon in the Nile flow.