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Te space-time dynamics of the occurrence of winter extreme events is investigated on the territory of Russia in 1970-2015 on the basis of daily observations at weather stations. It was found that a whole on the territory a noticeable increase in the occurrence of days with extremely high daily temperatures and daily precipitation and a decrease in the occurrence of extremely cold days was noted. Te most noticeable changes happened in the European part of Russia, where at the beginning of the XXI century occurrence of the extremes was greater than during the previous thirty years. Note also that at the beginning of XXI century in Southern Siberia increase of occurrences of both daily maximum and daily minimum temperature was concurrent. Tis combination appears to be caused by the increase in temperature variability in the region due to the alternation of winters with extreme frosts and warmer and wet winters. Te increase in the frequency of extremely high temperatures in the European part of Russia could have been caused by both general warming and the increased influence of AMO. An increase in the frequency of extreme high and low temperatures in the south of Siberia may be due to the formation of an anticyclonic circulation anomaly with a center near the coast of the Kara Sea, which is responsible for advection of cold air masses from the northeast. As well as cyclonic formation in southern Siberia, along the eastern periphery of which temperate latitudes can receive anomalously warm air from the subtropics.

Monthly precipitation and the 3-month Standardized Precipitation Index (SPI) were used to reveal the patterns of rainfall and severe drought frequency over the East European Plain in the period 1953–2011 in the opposite phases of the quasibiennial oscillation (QBO). Differences of precipitation and severe drought frequency in May and in June in the westward and eastward phases of the QBO phases are explained by circulation variations. The analysis indicates less frequent severe drought events over Ukraine and at the center of the European part of Russia in May in the westward QBO phase due to the intensification of the storm track over the East European Plain. The weather conditions in May and in June in the years of the westward QBO phase were more favorable for the yield. The difference of spring wheat yield in the westward and eastward QBO phase exceeds the same difference of winter wheat yield in the Central Black Earth region and in the south regions. Ukraine and the region to the east of the Sea of Azov are the most vulnerable areas of increased risk of severe drought during the active growing season at the end of the 20th and beginning of the 21st century.

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