Weather hazard interpretation and nowcast by radar

A method for modeling and tracking convective clouds within radar images is presented. An object modeling approach is used, based on the extraction of grayscale skeletons from 2-dimensionnal cross-section of 3-dimensional radar data. Grayscale skeletons are appropriate shape descriptors for non-rigid and heterogeneous objects, in which gray-level local maxima correspond to regions of interest. The modeling scheme is enhanced by linking meta-data to some chosen points of the skeleton; this provides a good representation of the weather scene in terms of hazards for an aircraft. Skeletons are stored within a graph structure and tracked among successive pictures by means of relaxation labeling processes. The deduced ad-vection field is used to nowcast the clouds evolution. Preliminary results are satisfying concerning advection forecast.