Banff weather by month
Banff runs from about -11°C in January to 18°C in July, with May the wettest month at 68 mm.
warmest month
July
18°C
coolest month
January
-11°C
wettest month
May
68 mm
worst air month
September
13 µg/m³
The whole year, month by month.
| Month | Avg temp | Rain | Sun | PM2.5 |
|---|---|---|---|---|
| January | -11°C | 19 mm | 141 h | 2 |
| February | -7°C | 51 mm | 177 h | 3 |
| March | -6°C | 26 mm | 257 h | 4 |
| April | 0°C | 42 mm | 305 h | 5 |
| May | 4°C | 68 mm | 345 h | 8 |
| June | 7°C | 64 mm | 402 h | 9 |
| July | 18°C | 13 mm | 445 h | 8 |
| August | 14°C | 61 mm | 359 h | 7 |
| September | 11°C | 34 mm | 298 h | 13 |
| October | 3°C | 35 mm | 239 h | 3 |
| November | -5°C | 25 mm | 133 h | 2 |
| December | -5°C | 25 mm | 103 h | 2 |
About 3,204 hours of sun a year. Roughly 47 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 2026-05-25. Full method, licences and the list of sources we rejected are on the methodology page.