The paper proposes the further development of algebra-algorithmic design and synthesis tools towards the development of OpenCL programs. The method for semi-automatic parallelization of cyclic operators is proposed. The particular feature of the approach consists in using high-level algebra-algorithmic program specifications (schemes) and rewriting rules technique. The developed tools provide the construction of parallel algorithm schemes by superposition of predefined language constructs of Glushkov’s system of algorithmic algebra, which are considered as reusable components. An algorithm scheme is a basis for the generation of corresponding source code in a target programming language. The approach is illustrated with an example of developing an OpenCL interpolation program used in a numerical weather forecasting. The results of the experiment consisting in executing the generated OpenCL program on a graphics processing unit are given.