In order to form an information base for predicting the development of diseases of agricultural crops, in particular, winter wheat, a correlation analysis was made of the links between the main meteo-data (temperature, precipitation, SCC) and the level of development and major diseases of winter wheat (brown rust, powdery mildew, root rot and spike fusarium) for a 36-year period (1972-2007). The original long-term meteo-data (“Moldgidrometeo” and meteorological stations of the Research Institute of Field Crops “Selectia”) were also structured in 3 soil-climatic regions of Moldova, subjected to mathematical processing (cluster and system analysis, etc.). The data of annual surveys of the republican plant protection station and the plant protection laboratory of the Research Institute of Field Crops Selectia for the same period were subjected to similar processing. As a result, a reliable correlation was established between the seasonal parameters of air temperature (mainly negative), precipitation volumes and SCC (mostly positive) with the level of development of winter wheat diseases (by the criterion of the percentage of occurrence of pathogens and the percentage of affected plants). The calculated coefficients of the level of correlation between these objects are the necessary information basis for the prognosis of the development of diseases (annual, seasonal and operational), including and on electronic media. In addition, an assessment was made of the consequences for the phytosanitary situation on winter wheat sowings for 2 possible scenarios: subsequent climate warming up to +10.5... + 11.5 °C (decrease in the level of development for brown rust, ear fusarium, and root rot (but, on the contrary, an increase in the percentage of affected plants); a possible cooling of the climate to +8.0... + 8.9 ° С (accented enhanced development of brown rust and fusarium ear, as well as root rot, but a decrease in the level of plant damage), in addition a moderate increase in the development of powdery mildew is predicted.