Rennes climate
Rennes (Brittany, France) has a temperate oceanic climate (Köppen Cfb). The average temperature over the year is 12 °C53 °F, and about 708 mm28 in of precipitation falls in an average year.
Temperature by month
Precipitation by month
Rennes climate table
| Month | High °C°F | Low °C°F | Mean °C°F | Precip. mmin | Frost days |
|---|---|---|---|---|---|
| Jan | 847 | 236 | 542 | 702.7 | 8 |
| Feb | 949 | 235 | 642 | 582.3 | 9 |
| Mar | 1254 | 338 | 846 | 572.3 | 5 |
| Apr | 1660 | 542 | 1151 | 461.8 | 1 |
| May | 1966 | 847 | 1457 | 572.3 | 0 |
| Jun | 2373 | 1253 | 1763 | 502.0 | 0 |
| Jul | 2476 | 1356 | 1966 | 481.9 | 0 |
| Aug | 2476 | 1356 | 1966 | 481.9 | 0 |
| Sep | 2271 | 1151 | 1661 | 421.6 | 0 |
| Oct | 1763 | 847 | 1355 | 753.0 | 0 |
| Nov | 1254 | 542 | 948 | 773.0 | 2 |
| Dec | 948 | 337 | 642 | 803.1 | 8 |
| Year | 2476 | 235 | 1253 | 70828 | 34 |
“Year” row: highest monthly high, lowest monthly low, annual mean and annual total. Frost days are for the whole grid cell.
| Month | Humid. | Cloud | Solar | Daylight |
|---|---|---|---|---|
| Jan | 92% | 73% | 1.0 | 8:46 |
| Feb | 88% | 70% | 1.8 | 10:09 |
| Mar | 84% | 67% | 3.0 | 11:45 |
| Apr | 79% | 62% | 4.5 | 13:36 |
| May | 78% | 66% | 5.3 | 15:10 |
| Jun | 76% | 65% | 5.7 | 16:02 |
| Jul | 74% | 61% | 5.6 | 15:41 |
| Aug | 75% | 60% | 4.8 | 14:18 |
| Sep | 76% | 57% | 3.8 | 12:30 |
| Oct | 85% | 67% | 2.2 | 10:43 |
| Nov | 90% | 70% | 1.2 | 9:09 |
| Dec | 93% | 71% | 0.9 | 8:22 |
Humid. = average relative humidity at 2 m; cloud = average cloud amount; solar = average daily solar energy reaching the ground in kWh/m² (all-sky); daylight in hours:minutes, calculated for the 15th of each month.
What the climate of Rennes is like
The warmest month is July, with an average high of 24 °C76 °F and a low of 13 °C56 °F. The coldest is January, when highs average 8 °C47 °F and lows 2 °C36 °F. There is a clear seasonal cycle, with 13.5 °C24.3 °F between the average temperature of the warmest and the coolest month.
Annual precipitation is moderate at about 708 mm28 in. Rain is spread fairly evenly through the year. The wettest month is December (80 mm3.1 in), the driest is September (42 mm1.6 in).
Relative humidity ranges from 74% in July to 93% in December. The clearest skies (lowest average cloud amount, 57%) are typical of September. Average wind speed near the ground ranges from 10 km/h (6 mph) in August to 12 km/h (8 mph) in February. Daylight lasts from about 8.4 hours in December to 16.0 hours in June.
Best time to visit Rennes
Based on these averages, the most comfortable months for sightseeing and outdoor activities are May–September: average highs of 19 °C66 °F to 24 °C76 °F with 42 mm1.6 in to 57 mm2.3 in of precipitation per month.
The most challenging month is December, which is cold, with average highs of 9 °C48 °F.
Comfort score: months are ranked by how close they come to an average high of 21–28 °C (70–82 °F), lows above 5 °C (41 °F), little precipitation and moderate humidity. The best-ranked months of each place are recommended, even where none meets all of these. These are general rules of thumb applied to long-term averages.
What to pack for Rennes
- Winter (December–February) — highs 847 to 9 °C49 °F, lows 235 to 3 °C37 °F, about 69 mm2.7 in of precipitation a month. Pack a warm coat, layers and closed shoes.
- Spring (March–May) — highs 1254 to 19 °C66 °F, lows 338 to 8 °C47 °F, about 54 mm2.1 in of precipitation a month. Pack long sleeves, a sweater and a medium jacket.
- Summer (June–August) — highs 2373 to 24 °C76 °F, lows 1253 to 13 °C56 °F, about 49 mm1.9 in of precipitation a month. Pack light layers — T-shirts plus a light sweater or jacket and an extra layer for the cooler mornings and evenings.
- Autumn (September–November) — highs 1254 to 22 °C71 °F, lows 542 to 11 °C51 °F, about 65 mm2.5 in of precipitation a month. Pack long sleeves, a sweater and a medium jacket.
How Rennes compares
Compared with Nantes, about 100 km to the south, Rennes is on average 0.3 °C0.6 °F cooler and receives 11% less precipitation (708 mm28 in vs 800 mm31 in). The difference is largest in June (0.6 °C1.1 °F cooler).
Of the 36 places in France covered by World Climates, Rennes is the 17th warmest by annual mean temperature and the 23rd wettest by annual precipitation. See all of them on the France climate page.
Places in other countries with the most similar temperature and rainfall pattern: Worthing (United Kingdom, Cfb), Southampton (United Kingdom, Cfb) and Gasteiz / Vitoria (Spain, Cfb).
Nearby places
- Nantes 100 km · 12 °C54 °F · 800 mm31 in
- Angers 110 km · 12 °C53 °F · 714 mm28 in
- Jersey (St Helier) 124 km · 12 °C54 °F · 772 mm30 in
- Le Mans 140 km · 12 °C53 °F · 707 mm28 in
- Caen 154 km · 12 °C53 °F · 745 mm29 in
- Guernsey (St Peter Port) 163 km · 12 °C54 °F · 847 mm33 in
- Tours 195 km · 12 °C53 °F · 698 mm27 in
- Le Havre 202 km · 12 °C53 °F · 803 mm32 in
Frequently asked questions
What is the warmest month in Rennes?
July is the warmest month in Rennes, with an average high of 24 °C (76 °F) and an average low of 13 °C (56 °F).
What is the coldest month in Rennes?
January is the coldest month, with an average high of 8 °C (47 °F) and an average low of 2 °C (36 °F).
When does it rain the most in Rennes?
December is the wettest month with about 80 mm (3.1 in) of precipitation; September is the driest with about 42 mm (1.6 in).
What is the best time to visit Rennes?
Judging by long-term averages, the most comfortable months are May–September.
About this data
All figures are 25-year averages (January 2001 – December 2025) from the NASA POWER project. Temperature, humidity, wind and precipitation come from the MERRA-2 reanalysis (precipitation is the bias-corrected MERRA-2 product), cloud and solar values from CERES satellite data. They describe a grid cell of roughly 50–70 km, not a single weather station, so they can differ from airport records — most of all on coasts, in mountains and for rainfall. Average highs and lows are the monthly mean temperature plus/minus half of the average daily temperature range. Counts of rainy days are not part of this dataset.