Solar interferences can be detected automatically in polar reflectivity data produced operationally by a weather radar. Using a linear model the collected solar interferences can be analyzed quantitatively, and thus the biases of the elevation and azimuth reading of the radar antenna and the received solar power can be extracted. In the presentation the methods for monitoring of the weather radars will be introduced. In addition, the impact of atmospheric attenuation and refraction of solar radiation received at low elevations and the accuracy of correction methods will be discussed. Finally, the potential of the sun for quantitatively monitoring of operational weather radars will be demonstrated by examples from the Finnish and Dutch weather radar networks.