This paper describes time-series backscatter measurements using BorealScat-2, which is a multi-polarization, multi-frequency tomographic radar. It is installed on a 50-m tower at a boreal forest site in northern Sweden. We describe the system and show measurements related to forest water dynamics during summer conditions. The measurements include data at P-, UHF- and L-band. Results show periodic diurnal variations for all frequency bands but with different phases and amplitudes depending on frequency band and polarization. The results indicate the potential of estimating forest water dynamics from radar data.