Tropical Climate Update

Australian region

Warm and dry fortnight sees increased fire activity

Over the past fortnight, daily maximum temperatures were typically 2–6 °C above average across southern and central parts of the Northern Territory, Queensland and Western Australia. In contrast, temperatures north of 20°S were generally near average for this time of year.

For the fortnight ending 21 September, there was little to no rainfall across most of northern Australia. The main exceptions were isolated areas along the Gulf Coast of the Northern Territory and Queensland's North Tropical Coast, which recorded totals between 25 to 100 mm.

Northern Australia has entered peak bushfire season, with active fires occurring across several regions, specifically in the Northern Territory. Hot, dry and windy conditions have elevated fire weather conditions, leading to severe fire danger warnings in parts of northern Australia.

October outlook

The long-range forecast for October shows rainfall is likely to be below average for most of Queensland and northern and eastern parts of the Northern Territory, while northern parts of Western Australia are likely to have above average rainfall for the month. However, October is typically a dry time of year for parts of northern and western Australia. Average October rainfall is generally below 10 mm for much of northern Australia, increasing to 10-25 mm in the northern parts of the Kimberley and exceeding 25 mm in the western Top End and eastern and south-east Queensland.

Both maximum and minimum temperatures are likely to be warmer than average for much of northern Australia, except in the far north and east, where cooler than average October temperatures are likely. 

Madden–Julian Oscillation

The Madden–Julian Oscillation (MJO) is currently in the Western Hemisphere, as of 20 September. Forecasts show it is most likely to remain in this sector over the coming days before weaking later in the month.

Tropical wind and cloudiness have been strongly influenced by El Niño since May, with westerly winds and increased cloudiness dominating the western to central tropical Pacific, and decreased cloudiness across the Maritime Continent.

International Conditions

Active tropical cyclone season to date for north-west and north-east Pacific regions

El Niño has historically enhanced the typhoon season in the north-west Pacific region, and the hurricane season in the north-east Pacific, but suppresses hurricane activity in the north Atlantic. The 2026 season is currently tracking to be an active season in both regions of the north Pacific, and well below average in the north Atlantic.

For the season to date, the north-east Pacific region has had 17 named storms, compared to the 1991-2020 to-date average of 12, according to the Joint Typhoon Warning Center.  

As of 21 September, the north-west Pacific season has had 25 tropical storms. During the last fortnight, just one typhoon has developed, Tropical Cyclone Dujuan, which is currently tracking close to Japan, where it is expected to bring heavy rainfall to parts of the country including the Tokyo metropolitan area.

Dry conditions across the Maritime Continent

The current strong El Niño has brought prolonged dry conditions to large parts of Indonesia. This dryness has exacerbated wildfires across the country in recent weeks, with smoke haze continuing to spread into several Southeast Asian countries.   

In Papua New Guinea, prolonged dry conditions combined with unusually severe frost events have reduced crop yields and lowered water storages.