| Month | 2011 | 2012 | 2013 | Normal | 2011 | 2012 | 2013 | Normal |
| Jan | 16.0 | 22.6 | 124.2 | 92.5 | 2.4 | 7.2 | 4.3 | 3.4 |
| Feb | 93.5 | 89.4 | 98.0 | 84.6 | 6.7 | 8.3 | 6.0 | 6.1 |
| Mar | 36.8 | 226.1 | 116.1 | 109.5 | 11.8 | 16.3 | 9.1 | 10.6 |
| Apr | 348.5 | 42.2 | 114.0 | 110.0 | 17.7 | 18.7 | 15.3 | 15.5 |
| May | 200.2 | 34.5 | 135.6 | 145.0 | 20.4 | 23.5 | 20.0 | 20.2 |
| Jun | 18.5 | 60.2 | 159.8 | 105.9 | 28.3 | 27.4 | 25.4 | 24.3 |
| Jul | 35.1 | 64.0 | 96.5 | 86.9 | 31.2 | 30.3 | 26.4 | 26.9 |
| Aug | 133.4 | 80.0 | 64.0 | 72.6 | 29.9 | 28.0 | 26.8 | 26.6 |
| Sep | 68.1 | 178.6 | 68.6 | 104.1 | 21.2 | 24.3 | 24.7 | 22.3 |
| Oct | 104.4 | 66.0 | 136.9 | 120.7 | 16.7 | 15.9 | 16.6 | 16.5 |
| Nov | 344.2 | 25.9 | 85.9 | 122.7 | 12.5 | 11.0 | 10.1 | 10.1 |
| Dec | 142.0 | 69.6 | 164.1 | 110.2 | 6.9 | 7.2 | 4.2 | 4.3 |
| Total/Mean | 1540.5 | 959.1 | 1363.7 | 1264.7 | 17.3 | 18.3 | 16.9 | 15.6 |