Neerslag — 2026
| Mois | Haarlem | Velsen | Différence |
|---|---|---|---|
| Jan | 90.4 mm | – | – |
| Fév | 79.8 mm | – | – |
| Mar | 36.6 mm | 0.7 mm | +35.9 |
| Avr | 4.3 mm | 3.2 mm | +1.1 |
| Mai | 49.5 mm | 41.4 mm | +8.1 |
| Juin | 100.9 mm | 77 mm | +23.9 |
| Juil | 14.4 mm | 17.7 mm | -3.3 |
| Aoû |
| 94 mm |
| 110 mm |
| -16.0 |
| Sep | 90.5 mm | 113.4 mm | -22.9 |
| Oct | 121.3 mm | 162.6 mm | -41.3 |
| Nov | 4 mm | 3.9 mm | +0.1 |
| Déc | – | – | – |