According to one embodiment, a weather radar apparatus includes a transmitting/receiving unit configured to transmit a radar wave to an observation target and receive a reflected wave, a distribution unit configured to distribute a received signal of the reflected wave to a main path and at least another path, an extraction unit configured to extract, from a signal of the other path, an interference wave signal extracted from another radio station, and a removing unit configured to remove the interference wave signal extracted from a signal of the main path.