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Of particular current importance in the general problem of global climate change is the regional manifestation of this process. The focus of this paper is concentrated on the transitional natural zones: forest tundra (st. Salekhard), and forest-steppe (st. Omsk) of the West Siberian Plain. The study is based on data for ground air temperatures and precipitation at the mean-daily and mean annual level, covering the time interval from 1936 to 2012. The observations are grouped in three periods: from 1936 to 1970, from 1971 to 2006, and from 2001 to 2012 thus making it possible to identify trends in the behavior of mean annual indicators, examine the intra-annual and seasonal changes, and to carry out a typification according to thermal regime and humidification regime. Regional changes in mean annual air temperatures at st. Salekhard and st. Omsk are representative of the general features of temperature variation over the entire observing period. In the Subarctic, however, the warming period became more pronounced in 2001, whereas it started in the 1970s in the forest-steppe, which is borne out by an increase in the recurrence frequency of warm and normal (according to thermal regime) years during the aforementioned periods. The southern part of the West Siberian Plain has experienced a more intense warming than in the north. Analysis of the intra-annual behavior of mean daily temperatures at st. Omsk showed their steady increase during the time interval from 1971 to 2012; this is especially true in regard to a warm season. At st. Salekhard the dynamics of temperatures is more complicated in character. Observation showed comparable (in duration) time spans with alternating increases and decreases in air temperature. The annual precipitation amounts for the time intervals used in the comparison indicated that their mean long-term value in the zones under consideration has increased for the last 35 years by 26 mm at st. Salekhard, and by 15 mm at st. Omsk. Considerable changes of climate have been observed since the 1970s; in high and mid-latitudes, they differ greatly and have influence on phenological phenomena, the structure of seasonal rhythms, the conditions of functioning of landscapes, and on human economic activity. [ABSTRACT FROM AUTHOR]