The simulation of the optical turbulence (OT) for astronomical applications obtained with non-hydrostatic atmospherical models at meso-scale presents, with respect to measurements, some advantages. Among these: (1) the possibility to provide 3D C2N maps above a region of a few tens of kilometers around a telescope. (2) the possibility to simulate the turbulence 'where' and 'when' it is desired without the need of long and expensive site testing campaigns done with several instruments. (3) the possibility to forecast the optical turbulence, goal considered a 'chimera' by all astronomers and fundamental element for the implementation of the flexible scheduling, crucial operation mode for the success of new class of telescopes (D > 10 m). The future of the ground-based astronomy relies upon the potentialities and feasibility of the ELTs. Our ability in knowing, controlling and 'managing' the effects of the turbulence on such a new generation telescopes and facilities are determinant to assure their competitiveness with respect to the space astronomy. In the past several studies have been carried out proving the feasibility of the simulation of realistic C2N profiles above astronomical sites. The European Community (FP6 Program) decided recently to fund a Project aiming, from one side, to prove the feasibility of the OT forecasts and the ability of meso-scale models in discriminating astronomical sites from optical turbulence point of view and, from the other side, to boost the development of this discipline at the borderline between the astrophysics and the meteorology. In this contribution I will present the scientific and technological goals of this project, the challenges for the ground-based astronomy that are related to the success of such a project and the international synergies that have been joint to optimize the results.