|Vegetation in Siberia is mostly taiga, with a tundra belt on the northern fringe, and a temperate forest zone in the south.|
Trans-Siberian Railway. The climate in this southernmost part is Humid continental climate (Koppen Dfb) with cold winters but fairly warm summers lasting at least 4 months. Annual average is about 0.5°C, January averages about−15 °C (5 °F) and July about +19 °C (66.2 °F), while daytime temperatures in summer typically are above 20 °C. With a reliable growing season, an abundance of sunshine and exceedingly fertile chernozem soils, Southern Siberia is good enough for profitable agriculture, as was proven in the early twentieth century.
The by far most common climate in Siberia is continental subarctic (Koppen Dfc or Dwc), with the annual average temperature about −5 °C (23 °F) and roughly −25 °C (−13 °F) average in January and +17 °C (62.6 °F) in July, although this varies considerably, with July average about 10 °C at the taiga - tundra ecotone. The southwesterly winds of Southern Siberia bring warm air from Central Asia and the Middle East. The climate in West Siberia (Omsk, Novosibirsk) is several degrees warmer than in the East (Irkutsk, Chita). With a lowest record temperature of −71.2 °C (−96.2 °F), Oymyakon (Sakha Republic) has the distinction of being the coldest town on Earth. But summer temperatures in other regions reach 38 °C (100.4 °F). In general, Sakha is the coldest Siberian region, and the basin of the Yana River has the lowest temperatures of all, with permafrost reaching 1,493 meters (4,898 ft). Nevertheless, as far as Imperial Russian plans of settlement were concerned, cold was never viewed as an issue. In the winter, southern Siberia sits near the center of the semi-permanent Siberian High, so winds are usually light in the winter.
Precipitation in Siberia is generally low, exceeding 500 millimeters (20 in) only in Kamchatka where moist winds flow from the Sea of Okhotsk onto high mountains – producing the region's only major glaciers, though the volcanic eruptions, and low summer temperatures allow limited forests to grow. Precipitation is high also in most of Primorye in the extreme south where monsoonal influences can produce quite heavy summer rainfall. Despite the region's notorious cold winters, snowfall is generally quite light, especially in the eastern interior of the region.