November 2016 – January 2017

The period November 2016 to January 2017 was influenced by a negative SAM. As is characteristic of a negative SAM, above average pressure was observed over Antarctica, with decreased pressure to the south of Australia, stretching into the southern Indian and Pacific oceans (see image).

Mean sea level pressure anomaly chart for November 2016 to January 2017 for the southern hemisphere. Base period is 1979–2000. Higher than average pressure is evident over Antarctica while lower than average pressure is located further north. Higher pressure near Antarctica and lower pressure in the mid-latitudes is a defining characteristic of negative SAM. *Data: ERA Interim*.

Australian rainfall deciles for November 2016 to January 2017 — Mean sea level pressure anomaly chart for November 2016 to January 2017 for the southern hemisphere. Base period is 1979–2000. Higher than average pressure is evident over Antarctica while lower than average pressure is located further north. Higher pressure near Antarctica and lower pressure in the mid-latitudes is a defining characteristic of negative SAM. *Data: ERA Interim*.

This pressure pattern suppressed rainfall over much of the eastern seaboard and southern Queensland by decreasing the amount of moist air from the ocean flowing into the region and instead delivering dry continental air from inland Australia. A handful of Queensland stations had their driest November on record.