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Extensive cold anticyclone swept most of Siberia and the Far East, capturing the territory of Mongolia. Now the anticyclone is at the stage of its maximum development, its power is 1062.5 hPa. In the coming days, its weakening and destruction will begin, the pressure at its center will drop to 1030.0 hPa.
Pressure + Temp over Siberia
© Gismeteo
Surface pressure map and minimum air temperature on December 6, 2018.
On Tuesday in the south of Eastern Siberia and the western regions of the Far East winter came with frosty weather, after which the frosts in the region intensified every day. The lowest air temperature in the Irkutsk Region is noted in Erbogachen: −47.2 degrees on 4 December. On the night of December 6, throughout the region, with the exception of areas of Baikal, the minimum air temperature was below 30 degrees below zero. In Irkutsk, the coldest night since the beginning of the winter period was observed today: −31.1 in the city, near the meteorological station, and −34.3 degrees near the airport.

Romanovka turned out to be the coldest place in the Republic of Buryatia, where the air temperature dropped to −40.5 degrees on December 5. In the regional center, in the city of Ulan-Ude, on the night of December 6, the temperature at night was −28.4 degrees.

In the Trans-Baikal Territory, it was coldest in the east of the region in Shelapugino: −45.4 degrees at night on December 6. In Chita, the night of December 5 was cold: minus 37.0.
Irkutsk Region Temp
© Gismeteo
The minimum air temperature in the Irkutsk Region, the Republic of Buryatia and the Trans-Baikal Territory is December 6, 2018.
In the following days, the frost will gradually decline.