Astana has one of the harshest climates of any national capital. Winters from late November to early March are brutally cold, with average daytime highs below minus 10 and frequent dips to minus 30 and lower. Summers from June to August can hit 35 with intense steppe sun. Wind blows year-round.
The best time to visit is late May to mid June or early September: pleasant temperatures, long daylight, the parks are green, the fountains are running, and the festival programme is in full swing. The Nauryz spring celebrations around 21 March are an interesting time to be in the city — concerts, public parties, traditional food stalls on the central squares — but the weather is still cold.
Winter is not without its appeal if you are prepared. The skating rinks, the warm interiors of Khan Shatyr, the snow-covered domes — there is a postcard quality to deeply frozen Astana, and the museums and galleries are reason enough to be outdoors for short periods. Pack the warmest clothing you own.
Avoid the deep winter (January, February) and the height of summer (late July, early August) if comfort matters.