Santiago has a mean annual temperature of 15.9 °C and receives 352 mm of precipitation per year (1991–2020 climate normals). The warmest month is January with a mean temperature of 23.4 °C, while July is the coldest month at 8.5 °C. Most precipitation falls in June (93 mm); the driest month is January (1 mm).
Climate Diagram
Walter–Lieth diagram: the red line shows monthly mean temperature (left axis, °C), the blue line monthly precipitation (right axis, mm). Yellow areas mark arid periods (temperature above precipitation), light blue humid periods, dark blue perhumid periods (above 100 mm/month, shown on a compressed 1:10 scale). Scale: 1 °C ≡ 2 mm.
Climate normals and Köppen-Geiger classification: Beck et al. (2023), Scientific Data 10, 724, CC BY 4.0. Period 1991–2020. Classification resolution ≈ 1 km; monthly climate data resolution ≈ 1 km (0.01°, Original 2023 release; predates the January 2026 correction), sampled at the grid cell containing the city coordinates (-33.45°, -70.67°). Climate normals describe the long-term average, not current weather.