WEATHER · CLIMATE NORMALS · 1991–2020
Santiago Climate — Averages by Month
What the weather in Santiago, CLaverages across a standard 30-year period. Each month's figure is the 1991–2020 mean temperature and total rainfall from the ERA5 reanalysis — the long-run normal a place settles around, not a forecast for any particular day.
Month-by-month normals
| Month | Avg temperature | Avg rainfall |
|---|---|---|
| January | 22.0 °C · warmest | 3.4 mm |
| February | 21.3 °C | 5.2 mm |
| March | 19.8 °C | 9.3 mm |
| April | 16.0 °C | 29.4 mm |
| May | 12.4 °C | 64.3 mm |
| June | 9.5 °C | 110.9 mm · wettest |
| July | 8.9 °C · coldest | 88.8 mm |
| August | 10.4 °C | 84.1 mm |
| September | 12.7 °C | 59.5 mm |
| October | 15.2 °C | 42.5 mm |
| November | 18.1 °C | 17.6 mm |
| December | 20.5 °C | 7.2 mm |
How to read these numbers
These are reanalysis normals, not readings from a single weather station. They come from the ERA5 0.25° (~25 km) global reanalysis grid, sampled at the grid cell nearest Santiago — centred at 33.50°S, 70.75°W. A reanalysis blends observations with a physics model onto an even grid, so a coastal or mountain city's cell can read a little cooler, warmer, wetter or drier than the city centre itself. The month-to-month shape — when it's hot, when it rains — is what these normals capture best.
“Normal” means the 1991–2020 average, the current World Meteorological Organization standard period. A normal is what a place tends toward over decades — any single day, month or year can and will depart from it.