The main objective of this study is to forecast the amount of rainfall over the Blue Nile Basin using meteosat satellite images and to establish the reliability of these estimates when compared to observations. The Blue Nile Basin has been selected as a study area because it supplies 85% of the water to Aswan (Up Stream Egypt). Most of the current techniques for estimating rainfall from temperature of the cloud tops associate rainfall with cold (high) clouds, assuming that these are the tops of

more »

... active storms. Four techniques are applied here for estimating the amount of rainfall over the Blue Nile Basin on daily basis. These techniques have been tested and calibrated with raingage data and the results show that there are some differences between the raingage data and the satellite estimates. Two techniques (Nfs-clim and GPI) gave better results, but some differences vary from month to month and year to year. The correlation coefficient between the satellite estimate and raingage observed mean areal precipitation over the Blue Nile Basin is found to be 0.65. One of these techniques (Nfs-clim) is applied here to forecast the amount of rainfall over the Blue Nile Basin. Work is currently underway to improve rainfall forecasts by collecting more data and including other satellite images.