Sudbury weather by month
Sudbury runs from about -7°C in January to 20°C in July, with April the wettest month at 156 mm.
warmest month
July
20°C
coolest month
January
-7°C
wettest month
April
156 mm
worst air month
July
12 µg/m³
The whole year, month by month.
| Month | Avg temp | Rain | Sun | PM2.5 |
|---|---|---|---|---|
| January | -7°C | 56 mm | 92 h | 3 |
| February | -5°C | 40 mm | 192 h | 6 |
| March | -1°C | 73 mm | 210 h | 5 |
| April | 5°C | 156 mm | 213 h | 5 |
| May | 13°C | 51 mm | 344 h | 5 |
| June | 17°C | 102 mm | 321 h | 6 |
| July | 20°C | 84 mm | 374 h | 12 |
| August | 19°C | 65 mm | 339 h | 10 |
| September | 16°C | 59 mm | 282 h | 5 |
| October | 9°C | 66 mm | 212 h | 4 |
| November | 3°C | 72 mm | 109 h | 2 |
| December | -6°C | 80 mm | 89 h | 2 |
About 2,777 hours of sun a year. Roughly 91 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 2026-05-24. Full method, licences and the list of sources we rejected are on the methodology page.