Isfahan, one of Iran's great historic cities, sits on the central Iranian plateau on the Zayanderud River at around 1,570 metres above sea level, at approximately 32.65°N, 51.68°E. Its high, interior position gives it a cold desert climate (Köppen BWk) — hot, very dry summers and cold winters — with abundant sunshine, low humidity and a wide day-to-night temperature range.

Summer, from June to August, is hot, extremely dry and sunny, with July the hottest month — highs around 36–37°C — though the altitude and desert dryness make the heat far more bearable than in the humid Gulf, and nights cool sharply, sometimes to the high teens. Rain is entirely absent for months, and the sky is almost permanently clear.

Winter, from December to February, is cold and dry, with January the coldest month — highs around 8–9°C and nights that regularly fall below freezing, near -4°C. Light snow falls occasionally, frost is common, and the days are crisp, clear and bright. This is the season when the little rain the city receives arrives.

Isfahan is extremely dry, receiving only around 120–130 mm of precipitation a year — true desert levels — with what falls concentrated between December and April, while the long summer is entirely rainless. The Zayanderud, the river running through the city, has run dry in recent years. Live rainfall, humidity, and pressure readings for the city are shown in the panels above.

Isfahan's plateau altitude gives it the crisp, dry, sunlit air for which the city and its blue-tiled domes are famous — hot summer days that cool sharply at night, and cold, clear winters. Its most pressing modern problem is water: the Zayanderud, once the lifeblood of the city, now frequently runs dry as upstream demand and drought bite.

To follow any single measurement in Isfahan more closely, use our live instruments: the online barometer for atmospheric pressure, the thermometer for temperature, the hygrometer for humidity, the anemometer for wind speed, the wind vane for wind direction, and the rain gauge for rainfall.