Bewolking — 2009
| Month | Court-Saint-Étienne | Ottignies-Louvain-la-Neuve | Difference |
|---|---|---|---|
| Jan | 65.7 % | – | – |
| Feb | 86.6 % | – | – |
| Mar | 67.6 % | – | – |
| Apr | 55.7 % | – | – |
| May | 63.5 % | – | – |
| Jun | 59.6 % | – | – |
| Jul | 61.1 % | – | – |
| Aug | 53.5 % | – | – |
| Sep |
| 60.5 % |
| – |
| – |
| Oct | 74 % | – | – |
| Nov | 78.7 % | – | – |
| Dec | 75.4 % | – | – |