Expect the unexpected when it comes to weather conditions in Le Mans. With racing conditions ranging from mild to severe, this circuit poses many different possibilities for race weekend. High average cloud coverage suggests persistent moisture levels in the air during the month of May. Now what this moisture results in is dependent on the air temperature. Warmer conditions will result in that wonderful muggy, humid environment that challenges a rider’s fitness and stamina. If the air takes a turn for the cooler conditions, rainfall can be expected as colder air has a smaller water holding capacity. May stands as a transition month for this region as it approaches a warmer summer but that is not to say that spring time weather is a guarantee!
Climate Factors of Study:
The following graphs track the average values of four different climate factors during April from 2012-2018. The Le Mans Bugatti Circuit is identified on each map by a black pin point, allowing you to see where the circuit lies within the range of values. The color key on the right hand side of each graph portrays average values for this region. Colors located at the top of the key represent higher values while colors located at the bottom represent lower values.
To recap from our Weather & Racing page:
- Outgoing long wave radiation:
- The level of outgoing long wave radiation detects how much radiation is being released from the earth back to the atmosphere. Low levels of OLR detects higher moisture levels that have resulted in cloud formation which ultimately traps the OLR and reflects it back to the earth’s surface.
- Humidity Levels:
- Humidity is the level of water vapor in the air. Warmer air has a higher ability of holding moisture and creating the humidity effect that we are all too familiar with. When the relative humidity reaches 100%, this means the air can’t hold any more moisture and it can lead to precipitation.
- The condensation of atmospheric water vapor. (The stuff that makes you want some wet tires on your bike)
- Average Air Temperature:
- In our case, this will be the average air temperature for a specific location/circuit during the race season to track fluctuation and ties to to the other climate factors.
Average Outgoing Longwave Radiation (OLR) May 2012-2018 (~235 W/m^2)
The Le Mans Bugatti Circuit experiences moderately low outgoing longwave radiation which suggests low sun exposure and high levels of cloud coverage. Falling around 10 W/m^2 below the average of all circuits in the series, the cloud coverage in Le Mans is able to trap outgoing radiation and retain heat close to the Earth’s surface which factors into the historically high circuit temperatures. Additionally, low OLR indicates high convective activity which not only contributes to cloud coverage but higher levels of moisture and therefore precipitation.
Average Air Temperature May 2012-2018 (~14 degrees Celsius)
Influenced by the mid Atlantic air traveling inland off the coast, Le Mans maintains fairly mild air temperatures with an average reading of 14 degrees celsius during the month of May. While the spectators may be preferring these conditions, riders often face challenges when it comes to racing in cooler temperatures. These mild temperatures contribute to the average rainfall as cooler air has a smaller water holding capacity.
Average Surface Precipitation Rate May 2012-2018 (~2 mm/day)
This region of France experiences nearly constant rainfall year round, with moderate precipitation throughout all months. Due to the unpredictable fluctuation in air temperature, rainfall will occur if air temperatures drop enough to a point where it can no longer retain moisture and instead, will condense and produce wet conditions. Because of the low OLR readings, we can assume cloud coverage is common in this region and therefore, moisture is generally present (either as humidity or rainfall depending on air temp).
Average Relative Humidity April 2012-2018 (~78%)
Falling just above the average humidity levels for all circuits included in the series, Le Mans has the potential to present muggy conditions. Humidity is dependent on air temperature as warmer air has a higher water holding capacity. May is a transition month for this region into the warmer season so humidity can be expected.