Bewolking — 2026
| Month | Katwijk | Voorschoten | Difference |
|---|---|---|---|
| Jan | – | – | – |
| Feb | – | – | – |
| Mar | 52.8 % | 54.1 % | -1.3 |
| Apr | 78.4 % | 78.7 % | -0.3 |
| May | 57.7 % | 58.6 % | -0.9 |
| Jun | 59.4 % | 61 % | -1.6 |
| Jul | 49.8 % | 49.2 % | +0.6 |
| Aug |
| 52.1 % |
| 53.9 % |
| -1.8 |
| Sep | 72.8 % | 72.4 % | +0.4 |
| Oct | – | – | – |
| Nov | – | – | – |
| Dec | – | – | – |