| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Average high °C (°F) | 6.9 (42.6) | 7.1 (44.8) | 12.2 (54.0) | 19.3 (66.7) | 23.1 (73.6) | 27.5 (81.5) | 31.0 (87.8) | 30.2 (86.4) | 26.1 (79.0) | 19.4 (66.9) | 12.7 (54.9) | 7.8 (46.0) |
| Daily mean °C (°F) | 1.5 (34.7) | 2.4 (36.3) | 6.8 (44.2) | 13.0 (55.4) | 17.0 (62.6) | 21.0 (69.8) | 24.5 (76.1) | 23.7 (74.7) | 19.8 (67.6) | 13.6 (56.5) | 7.8 (46.0) | 3.4 (38.1) |
| Average low °C (°F) | −1.5 (29.3) | −0.8 (30.6) | 3.0 (37.4) | 8.1 (46.6) | 12.1 (53.8) | 16.0 (60.8) | 19.4 (66.9) | 18.6 (65.5) | 15.0 (59.0) | 9.4 (48.9) | 4.5 (40.1) | 0.5 (32.9) |
| Precipitation mm (inches) | 20 (0.79) | 29 (1.14) | 31 (1.22) | 51 (2.01) | 84 (3.31) | 84 (3.31) | 41 (1.61) | 43 (1.69) | 35 (1.38) | 41 (1.61) | 35 (1.38) | 23 (0.91) |
| Avg. precipitation days (≥ 1 mm) | 4.0 | 4.0 | 5.9 | 7.0 | 9.7 | 8.7 | 5.7 | 5.7 | 5.0 | 5.0 | 4.4 | 4.0 |
| Sunshine hours | 99.2 | 104.4 | 142.6 | 171.0 | 213.9 | 249.0 | 267.3 | 248.0 | 207.0 | 164.3 | 102.0 | 93.0 |
