Receiving climate data from observed ground stations is typically difficult and expensive. This study compares observed data from 9 dispersed weather stations across the Euphrates River Basin, Iraq, to NASA POWER reanalysis products for daily, monthly, and annual precipitation, maximum (Tmax), and minimum (Tmin) air temperatures. Results demonstrated well-reliable for each of the NASA POWER products and observed data for all parameters. The coefficient of determination (R2) for precipitation, maximum temperature, and minimum temperature, respectively, ranges from 0.74 to 0.91, 0.74 to 0.94, and 0.72 to 0.95. The respective ranges for the Nash and Sutcliffe efficiencies (NSE) are 0.74 to 0.84, 0.63 to 0.85, and 0.4 to 0.75. Comparatively, the mean bias error (MBE) lies within the ranges of 0.19 to 1.61, −0.53 to +0.03, and +0.37 to +1.5, respectively. For precipitation products, NASA POWER has produced results on three different timescales that are satisfactory. The accuracy of the NASA product was good in humid regions of the west and northwest, but it declined in arid, and semi-arid regions, like the desert. Results demonstrate that NASA POWER can be effective in creating weather data sets in the absence or inaccessibility of ground weather station data.