The July 2007 negative SAM event was the second-strongest negative monthly winter value on record. Higher than average pressures occurred around Antarctica and lower than average pressures in the southern parts of the Atlantic and Indian oceans, as well as large parts of the southern Pacific Ocean (see image). This meant the belt of westerly winds had shifted towards the equator, bringing more storm systems to southern Australia.
The July 2007 rainfall followed a typical negative SAM pattern for winter, with above average rainfall in southern Victoria and southwest Western Australia, and suppressed rainfall over New South Wales. However, Tasmania had a drier than average month; the opposite from what may have been expected with a negative SAM.