Tropical Climate Update

Australia records twelve tropical cyclones for the 2024–25 season

Tropical low 30U dissipated on 28 April, and with no tropical cyclones or tropical lows across the Australian region forecast for the next 7 days, the official 2024–25 tropical cyclone season is expected to conclude quietly.

Based on post event reanalysis, tropical low 25U briefly reached tropical cyclone (TC) intensity near the Cocos Islands on 19 March, and thus has been reassigned as an unnamed tropical cyclone. It means that there were 12 TCs in the Australia region during the 2024–25 season; the highest number since 2005–06 which also saw 12 TCs. Eight TCs reached severe strength, also the most since 2005–06.  

Severe TC Alfred was the only TC that developed over the Coral Sea in the eastern Australia region during the season. Alfred caused widespread damage across south-eastern Queensland and north-eastern New South Wales when it made landfall in early March.

The remaining 11 TCs developed in the Indian Ocean in the western Australian region.  Three TCs or their remnants (severe TC Zelia, TC Dianne, and ex-severe TC Errol) crossed the northern Western Australia coast between February and April.

The Northern Territory was not directly impacted by TCs, for the first time since 2020–21. However, monsoon bursts and tropical lows, such as 30U, brought rain to parts of the Northern Territory during the wet season.

Recent rainfall confined to far northern Australia

Tropical low 30U and an associated trough over the north of Australia brought rainfall to north-eastern parts of the Northern Territory, the Peninsula and Gulf Country districts in Queensland, and the west Kimberley in Western Australia. For the week ending on 28 April, weekly totals exceeded 100 mm to 300 mm in Arnhem coastal locations in the Northern Territory and for the north coast and Torres Strait Islands in Queensland.

The highest weekly total (at a Bureau gauge), for the week ending on 28 April, was 347.8 mm at Gove Airport in the Northern Territory.

Northern Australian dry season starts

The northern Australia dry season officially starts on 1 May. Forecasts for the first week of May indicate typical dry season weather conditions are expected over the Australian tropics, including the Northern Territory's Top End and the Kimberley region of Western Australia.

Rainfall is forecast to contract offshore with dry south-easterly trade winds dominating northern Australia during the first few days of May.  However, humidity, isolated showers, and the chance of Gulf Lines will return to the Top End of the Northern Territory, particularly over parts of Arnhem Land, from the first weekend in May as the winds tend easterly and an Equatorial Rossby wave moves through.

Madden-Julian Oscillation likely to be weak or indiscernible into early May

The Madden–Julian Oscillation (MJO) remained indiscernible for most of April, except for a brief strengthening in the last couple of days. As of 26 April, a weak pulse of the MJO was located in the Western Pacific region.

Most models agree the MJO is likely to be weak or indiscernible in and about the Western Pacific for the next fortnight. The influence of the MJO on rainfall and tropical cyclone activity across northern Australia lessens significantly once the dry season commences.