| Year | October | November | December | January | February | March | April | May | Total | |
| 2009-2010 | 0.0 | 0.0 | 19.1 | 3.7 | 12.3 | 0.6 | 35.7 | |||
| 2008-2009 | 0.0 | 4.7 | 35.6 | 5.5 | 11.0 | 9.7 | 0.1 | 0.0 | 66.6 | |
| 2007-2008 | 0.0 | 2.3 | 22.5 | 23.3 | 26.4 | 4.3 | 0.6 | 0.0 | 79.4 | |
| 2006-2007 | 0.0 | 2.0 | 3.6 | 10.0 | 15.2 | 10.0 | 4.1 | 0.0 | 44.9 | |
| Most | 0.0 | 4.7 | 35.6 | 23.3 | 26.4 | 10.0 | 4.1 | 0.0 | 79.4 | |
| Least | 0.0 | 0.0 | 3.6 | 3.7 | 11.0 | 0.6 | 0.1 | 0.0 | 44.9 | |
| OSH Average | 0.1 | 4.0 | 10.9 | 12.4 | 7.2 | 7.6 | 1.5 | T | 43.7 | |
| 2-Mar-10 | ||||||||||