Climate averages 1991–2020
Peterborough, Canada weather
in September.
A mild, moderately wet month: the 4th warmest and the joint 7th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
September is a mild month in Peterborough, Canada: daytime highs average 20.7°C and nights cool to about 12.6°C. By daytime temperature it is the 4th warmest of the 12 months.
Expect about 85 mm of rain on roughly 10 days, which makes September a moderately wet month (the joint 7th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 12 h 34 min on an average September day.
The nearest other city in this atlas is Oshawa (62 km away). In September its highs average 20.8°C, about as warm as Peterborough, Canada, with 80 mm of rain.
Among the 86 cities listed in Canada, Peterborough, Canada ranks joint 26th of 86 for the warmest September highs and joint 42nd of 86 for the driest September (rainfall, lowest first). The mean September high of those 86 cities is 19.8°C; Peterborough, Canada is 0.9°C warmer than that mean.
From September to October, average highs fall by 7.4°C to 13.3°C, and monthly rainfall stays at 85 mm.
The annual picture
September in context
Monthly precipitation
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Peterborough, Canada climate table
| Month | Average highHigh / low | Average low | Precipitation mm/month | Wet days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | -3.1°C-12.0°C | -12.0°C | 68 | 10.7 | 9.39 h |
| February | -1.9°C-11.5°C | -11.5°C | 53 | 8.3 | 10.410 h |
| March | 3.5°C-6.1°C | -6.1°C | 62 | 10.3 | 11.912 h |
| April | 11.0°C1.2°C | 1.2°C | 87 | 11.5 | 13.413 h |
| May | 18.5°C8.4°C | 8.4°C | 82 | 10.7 | 14.815 h |
| June | 23.4°C14.1°C | 14.1°C | 92 | 10.9 | 15.515 h |
| July | 25.8°C17.0°C | 17.0°C | 88 | 10.9 | 15.215 h |
| August | 24.7°C16.4°C | 16.4°C | 85 | 10.5 | 14.014 h |
| September, selected | 20.7°C12.6°C | 12.6°C | 85 | 9.6 | 12.613 h |
| October | 13.3°C6.3°C | 6.3°C | 85 | 11.5 | 11.011 h |
| November | 6.2°C-0.1°C | -0.1°C | 74 | 10.3 | 9.710 h |
| December | 0.3°C-6.7°C | -6.7°C | 68 | 10.6 | 8.99 h |
Precipitation (rain or snow, as water) is the average of the 30 separate monthly totals. A wet day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
September in nearby cities
- Oshawa in SeptemberCanada · 62 kmHigh 20.8°C · Low 14.4°C · 80 mm rain
- Whitby in SeptemberCanada · 68 kmHigh 21.0°C · Low 14.5°C · 80 mm rain
- Ajax in SeptemberCanada · 76 kmHigh 21.0°C · Low 14.3°C · 85 mm rain
- Pickering in SeptemberCanada · 79 kmHigh 20.3°C · Low 13.5°C · 78 mm rain
- Markham in SeptemberCanada · 90 kmHigh 21.1°C · Low 13.3°C · 81 mm rain
- Newmarket in SeptemberCanada · 96 kmHigh 20.8°C · Low 12.2°C · 73 mm rain
- Richmond Hill in SeptemberCanada · 101 kmHigh 20.9°C · Low 12.7°C · 69 mm rain
- Thornhill in SeptemberCanada · 104 kmHigh 21.0°C · Low 13.7°C · 69 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Peterborough) is explained once on the Peterborough, Canada year overview and on the Sources, method and limits page.