The majority of canopy interception models, simulating the driving processes that control the energy and water exchange between the canopy and the atmosphere, contain parameters that can not be measured directly, but can only be meaningfully inferred by calibration against a measured record of input-output data. The aim of the present paper is to explore the suitability of two different types of measurements for the identification of parameters in a single-layer forest canopy interception model. The first information source consists of measured throughfall dynamics, whereas the second consists of measured canopy water storage dynamics. The latter measurements were obtained using the attenuation of a microwave signal over a 12.5-m propagation line while scanning vertically through the forest canopy. Results demonstrate that measured throughfall dynamics contain only very limited information for the calibration of a canopy interception model and are particularly inadequate to identify the storage capacity and evaporation rate of the forest canopy. On the contrary, microwave-measured canopy water storage dynamics contain sufficient information to be able to identify the interception model parameters with a high degree of confidence.