Bewolking — 2020
| Maand | Ridderkerk | Zwijndrecht | Verschil |
|---|---|---|---|
| Jan | 78.3 % | 76.4 % | +1.9 |
| Feb | 74.4 % | 75.2 % | -0.8 |
| Mrt | 52.9 % | 52.2 % | +0.7 |
| Apr | 36 % | 33.7 % | +2.3 |
| Mei | 47.2 % | 47.6 % | -0.4 |
| Jun | 65 % | 64 % | +1.0 |
| Jul | 62.3 % | 61.9 % | +0.4 |
| Aug |
| – |
| – |
| – |
| Sep | – | – | – |
| Okt | – | – | – |
| Nov | – | – | – |
| Dec | – | – | – |