The solar energy potential of the northeastern part of Saudi Arabia is investigated based on measurements of a complete year of data at a coastal location near Dhahran. High-resolution, real-time solar radiation data were collected and processed. Hourly, daily, and monthly statistics of solar radiation were made from the recorded 1-min averaged values. Clearness index is discussed on the basis of hourly, daily, and monthly averages. Variation of the diffuse fraction of total radiation is also determined and results are discussed.