Tropical Climate Update

Below-average rainfall in Australia's tropical north during the coming weeks

The Madden–Julian Oscillation (MJO) strengthened slightly during the past week as it tracked from the western to eastern Indian Ocean. However, it is relatively weak, and most climate models predict further weakening as it approaches the western Maritime Continent. Based on model output of rainfall, the MJO and other tropical waves are unlikely to lead to widespread above-average rainfall across the tropics to Australia's north in the next few weeks.

Read more about the Bureau's MJO monitoring.

Indian Ocean temperature pattern is dominant climate driver for Australia

Average to cooler-than-average sea surface temperatures (SSTs) are apparent across the broader Maritime Continent region, including waters to the north of Australia and the eastern Indian Ocean. Further west, much of the central to western Indian Ocean is warmer than average. This pattern is consistent with a positive Indian Ocean Dipole (IOD) and is likely the primary climate driver influencing rainfall across much of Australia. A positive IOD is typically associated with drier than normal conditions across much of northern Australia during the southern hemisphere spring and into the early part of the northern Australian wet season (typically, October to mid-December).

To the east of Australia, SSTs in the western Pacific Ocean are above average and predicted to remain so for the coming months. With large swathes of warmer-than-average waters away from northern Australia, and average to cooler-than-average waters locally across the region, cloudiness and rainfall is likely to be below average across northern Australia and much of the Maritime Continent for the next few months.

Tropical cyclone activity in western North Pacific Ocean

Tropical storm Bailu (Ineng) which developed to the east of the Philippines, passed just to the south of Taiwan before it made landfall on the southeast coast of mainland China in recent days. It has since weakened and dissipated. Bailu (Ineng) generated very heavy rain over the northern Philippines and Taiwan prior to reaching mainland China. Event rainfall totals in excess of 500 mm across eastern and southern Taiwan were reported. Flooding and landslides were also reported.

Tropical storm Podul (Jenny), which formed earlier today off the northeastern coast of the Philippines, is forecast to track towards Luzon, northern Philippines, where it is expected to make landfall in the next 24 hours. After crossing the Philippines, the system is expected to re-intensify and move towards the island of Hainan, off the southern mainland China coast.

For information on tropical cyclones in this region, visit the Japan Meteorological Agency.