Drought is one of the natural hazards that affect human life and usually occurs from a deficiency of precipitation and water availability from expected or normal amounts. This natural hazard can easily be monitored using a data from remote sensing and in- situ hydro-meteorological variables. Hence, the book illustrates remote sensing evapotranspiration from GEONETCast and in-situ data streams applied for drought monitoring and early warning: it is a case study for the Amhara region in the northern part of Ethiopia