Climate averages 1991–2020
Rennes weather
in August.
A warm, moderately wet month: the warmest and one of the driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
August is a warm month in Rennes: daytime highs average 23.2°C and nights cool to about 14.3°C. By daytime temperature it is the warmest month of the year.
Expect about 46 mm of rain on roughly 8 days, which makes August a moderately wet month (one of the driest months of the year). Daylight, from sunrise to sunset, lasts about 14 h 19 min on an average August day.
The nearest other city in this atlas is Nantes (100 km away). In August its highs average 23.9°C, 0.8°C warmer than Rennes, with 47 mm of rain.
Among the 57 cities listed in France, Rennes ranks 48th of 57 for the warmest August highs and joint 14th of 57 for the driest August (rainfall, lowest first). The mean August high of those 57 cities is 25.0°C; Rennes is 1.8°C cooler than that mean.
From August to September, average highs fall by 2.7°C to 20.5°C, and monthly rainfall rises from 46 mm to 49 mm.
The annual picture
August in context
Monthly rainfall
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
Rennes climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 8.4°C3.3°C | 3.3°C | 64 | 11.2 | 8.89 h |
| February | 9.4°C2.9°C | 2.9°C | 53 | 9.9 | 10.210 h |
| March | 12.2°C4.6°C | 4.6°C | 52 | 10.5 | 11.912 h |
| April | 14.9°C6.3°C | 6.3°C | 58 | 11.1 | 13.614 h |
| May | 18.1°C9.5°C | 9.5°C | 63 | 10.8 | 15.215 h |
| June | 21.2°C12.4°C | 12.4°C | 53 | 9.0 | 16.016 h |
| July | 23.1°C14.2°C | 14.2°C | 46 | 7.8 | 15.616 h |
| August, selected | 23.2°C14.3°C | 14.3°C | 46 | 8.2 | 14.314 h |
| September | 20.5°C12.2°C | 12.2°C | 49 | 8.2 | 12.613 h |
| October | 16.3°C9.7°C | 9.7°C | 69 | 11.4 | 10.911 h |
| November | 11.8°C6.2°C | 6.2°C | 65 | 11.3 | 9.39 h |
| December | 8.8°C3.7°C | 3.7°C | 71 | 12.1 | 8.48 h |
Rainfall is the average of the 30 separate monthly totals. A rain 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
August in nearby cities
- Nantes in AugustFrance · 100 kmHigh 23.9°C · Low 15.3°C · 47 mm rain
- Angers in AugustFrance · 110 kmHigh 24.5°C · Low 15.2°C · 46 mm rain
- Saint Helier in AugustJersey · 124 kmHigh 18.5°C · Low 16.1°C · 63 mm rain
- Le Mans in AugustFrance · 140 kmHigh 24.1°C · Low 14.9°C · 47 mm rain
- Caen in AugustFrance · 154 kmHigh 22.6°C · Low 14.5°C · 60 mm rain
- Tours in AugustFrance · 195 kmHigh 25.2°C · Low 15.7°C · 48 mm rain
- Le Havre in AugustFrance · 202 kmHigh 21.2°C · Low 15.3°C · 73 mm rain
- Brest, France in AugustFrance · 210 kmHigh 19.1°C · Low 14.9°C · 53 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 Rennes) is explained once on the Rennes year overview and on the Sources, method and limits page.