Calgary weather by month
Calgary runs from about -10°C in January to 20°C in July, with June the wettest month at 110 mm.
warmest month
July
20°C
coolest month
January
-10°C
wettest month
June
110 mm
worst air month
September
15 µg/m³
The whole year, month by month.
| Month | Avg temp | Rain | Sun | PM2.5 |
|---|---|---|---|---|
| January | -10°C | 22 mm | 173 h | 8 |
| February | -5°C | 27 mm | 197 h | 9 |
| March | -5°C | 45 mm | 231 h | 9 |
| April | 4°C | 52 mm | 291 h | 10 |
| May | 9°C | 84 mm | 324 h | 9 |
| June | 13°C | 110 mm | 391 h | 8 |
| July | 20°C | 28 mm | 444 h | 10 |
| August | 17°C | 75 mm | 367 h | 9 |
| September | 14°C | 51 mm | 307 h | 15 |
| October | 7°C | 15 mm | 258 h | 6 |
| November | -5°C | 37 mm | 135 h | 9 |
| December | -4°C | 11 mm | 142 h | 9 |
About 3,260 hours of sun a year. Roughly 57 rainy days a year.
These are long-run climate normals, not a forecast. A given year can sit well outside them. PM2.5 is a global model: near the coast it counts sea salt as fine particulate and reads high against ground stations, sometimes by a factor of two. Use the shape of the year, not the absolute number.
where these numbers come from
- · Temperature, rainfall and sunshine: ECMWF ERA5 reanalysis climate normals via Open-Meteo (CC BY 4.0), fetched once and stored.
- · PM2.5: Copernicus CAMS reanalysis, monthly means. Modelled, not station readings; near coasts CAMS counts sea salt as PM2.5 and reads high.
Last reviewed 2026-05-23. Full method, licences and the list of sources we rejected are on the methodology page.