Arequipa, Peru's second city, sits in the Andes of southern Peru at around 2,335 metres above sea level, in a valley overlooked by the volcano El Misti, at approximately -16.41°S, 71.54°W. Its high altitude and position in the rain shadow of the Andes give it a cold desert climate (Köppen BWk) — mild, exceptionally dry and brilliantly sunny year-round.

There is no summer in the temperate sense: temperatures stay mild and remarkably steady, with daytime highs around 21–23°C all year and cool nights near 7–9°C, thanks to the altitude. The brief wet season, from January to March, brings some cloud and occasional afternoon showers — the only rain of the year — though even then the sun usually returns.

There is no true winter, but the long dry season from April to December brings brilliantly clear, sunny days around 22°C and cold nights that can drop close to freezing, especially in June and July. Arequipa is famous for its almost unbroken sunshine, earning it the nickname 'the White City' beneath its dazzling volcanic skies.

Arequipa is extremely dry, receiving only around 90–110 mm of rain a year — true desert levels — almost all of it in the brief wet season from January to March, while for the remaining nine months it essentially never rains. Live rainfall, humidity, and pressure readings for the city are shown in the panels above.

Arequipa enjoys some of the most reliable sunshine anywhere, with over 300 clear days a year, thanks to its high-altitude position in the rain shadow of the Andes above the coastal desert. The active volcano El Misti looms over the city, and its ash has occasionally dusted the streets, while nearby volcanic eruptions can affect regional air quality.

To follow any single measurement in Arequipa 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.