In European Russia, summer days from late May to early September are warm and very long. At midsummer in St Petersburg there is no real darkness. Average temperatures range from 18-25 C. Autumn is brief and by the end of October, winter sets in, bringing with it lots of snow and extremely low temperatures. Spring arrives with a vengeance, heralding the great thaw, in late March and April.
Mongolia experiences four very distinct seasons with winter lasting from November to February, spring from March to May, summer until August and autumn during September and October. Summer is peak travel season when the weather is fine. The sunshine can be intense with almost zero humidity and occasional cloud cover. August is the wettest month of the year though by September and October the temperatures are cool, the rain eases up and the changing colours make for spectacular scenery. November sees the onset of the incredibly cold but dry winter months when snow often blankets the ground.
The autumn months of September to early November are a wonderful time to visit Beijing and northern China when the skies are clear and the days breezy. The winter months of late November to February are cold and windy yet the occasional snows can make the city look beautiful when it settles over the Great Wall and other historical monuments. Spring is dry, warm and hazy, and temperatures surge from May onwards. Late summer sees heavy rainstorms with July and August the wettest months of the year.