Hi Sergey,
The reason that there is no rain seen in the IMS radar picture is that their radar is not working. This affects the IMS rain map which is based on a combination of the radar map and automatic real time rain measurements. As most of this afternoon's rain was just off shore it does not show up in the IMS map. The WRF prediction may have been a bit optimistic and 2 hours early in the prediction time but it was close to reality.
For the last few years the WRF 4km model has shown an excellent track record in predicting precipitation, comparable and even better that the IMS COSMO model.
David