Bewolking — 2026
| Month | Heiloo | Alkmaar | Difference |
|---|---|---|---|
| Jan | – | 83.1 % | – |
| Feb | – | 78.5 % | – |
| Mar | 51.2 % | 58.8 % | -7.6 |
| Apr | 79.9 % | 80.7 % | -0.8 |
| May | 57.7 % | 55.8 % | +1.9 |
| Jun | 59.8 % | 59.4 % | +0.4 |
| Jul | 51.9 % | 53.8 % | -1.9 |
| Aug |
| 51.5 % |
| 50.3 % |
| +1.2 |
| Sep | 69.9 % | 68.7 % | +1.2 |
| Oct | – | – | – |
| Nov | – | – | – |
| Dec | – | – | – |