Forecasting upcoming weather conditions of vegetation and grain-crop yield in the dry-steppe zone of the pre-Ural Region

The long-term forecast of yield and vegetation conditions of grain crops for the dry-steppe zone of the pre-Ural Region is made for the first time based on new predictors and their time lags. The forecast is developed for the value of the predictant (Y) and all predictors (X) that are included in the multiple regression models. The obtained results permit the probability of the onset of drought in the expected year to be described in advance (5–6 months before the start of field works). The developed models indicate that a strong drought is expected for grain crops in 2017 (the winter wheat yield of 2–3 c grain/ha), which is due to unfavorable weather conditions in June (the precipitation of 3–4 mm) and high air temperature in July (the average temperature in the first decade of 25.2°C and maximum temperature of 37.5°C). This information makes it possible to choose the optimal technological solutions for overcoming the influence of unfavorable conditions. The methods of step-by-step multiple regression and neural network regression and the method of residual deviations in combination with the method of superposition of epochs are used.