Keywords: reservoirs, Dnipro River, appearance of ice, long-term forecasting, prognostic dependencies, heat flow coefficient

Reliable and efficient water management is impossible without information on the current and future condition of river basins. Timely informing stakeholders about the future development of hydrological processes is based on a system of hydrological forecasts. Long-term forecasts of ice phenomena are of great importance, as they are used to plan the end of navigation and the crossing of economic facilities to winter regime. Reliable and lead-time forecasts of appearance dates of ice phenomena and freeze-up on reservoirs are essential for the rational use of water resources and for establishing reservoir operation regimes that take into account the requirements and interests of various economic sectors: hydropower, shipping, fisheries, utilities, etc. The appearance dates of floating ice are one of the most important characteristics of autumn ice phenomena. In recent years, the frequency of warm seasons in autumn and pre-winter has increased, and the process of ice formation is often protracted. In such conditions, it is of great importance to forecast the appearance dates of stable ice and the dates of freeze-up, as these characteristics determine the most effective hydrological strategy in the autumn-winter period. The paper investigates the relationship between heat flow coefficients and the appearance dates of ice phenomena in the reservoirs of the Dnipro cascade. The received forecasting dependencies revealed very weak and moderate correlations, and the efficiency of the forecasting equations was 60 % or less. Thus, the use of heat flow coefficients as predictors of atmospheric processes is very limited. That is why the search for predictors of atmospheric processes should be expanded for long-term forecasting of the appearance dates of ice phenomena in space and time.

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