Abstract: A novel compression algorithm for weather radar data based on parallel adaptive coding is presented. Considering the specialty of radar data, some efficient pre-processing algorithms for the data such as coordinate transformation algorithm, vector field holding algorithm and scalar filter algorithm are given first. Then the parallel adaptive coding algorithm is used to compress the pre-processed data. Experimental results show that for the weather radar data, the proposed parallel adaptive algorithm achieves good Power Signal to Noise Ratio (PSNR) even in low bit rate.