It is well known that agricultural productions are sensitive to climate variability. In fact, specific climatic characteristics are required by some crops. In this approach, we provide information about the 1949 to 2001 cereal productivity response in Spain to precipitation, temperature and weather regimes. The preliminary results suggested the significant effects of precipitation and maximum temperature corresponding to May. The cyclonic weather regime towards the south-western part of the Iberian peninsula and the negative phase of the NAO affects cereal productivity as well. The relationships found would be useful to project impacts on agriculture from future climatic conditions. Empirical orthogonal functions, correlation and composite analyses were the methods used to filter signals of observed climate variations and to relate them to cereal productivity. Climatic data from the Spanish Meteorological Institute and from NCEP/NCAR reanalysis and agricultural productions from the Spanish Ministry of Agriculture are used to perform the study.