Tropical Climate Update

Australian region

Recent conditions

For the week ending 13 October, isolated thunderstorms and showers brought light to moderate rainfall to parts of tropical northern Australia. Weekly rainfall totals of 10 to 50 mm, with locally higher totals up to 100 mm, were recorded across parts of the Kimberley, Cape York Peninsula and the north of the Northern Territory. A daily total of 95.2 mm was recorded at Old Delamere in the Northern Territory in the 24 hours to 9 am on 12 October.

Further south, a cloud band associated with surface troughs across inland Australia brought showers and isolated thunderstorms, some severe, to parts of central and eastern Australia. Weekly rainfall totals of 10 to 50 mm were recorded across isolated parts of the southern Northern Territory and south-eastern Queensland.

Maximum temperatures for the week were above average for most of northern Australia, with temperatures more than 4 °C above average for parts of the southern Northern Territory and more than 6 °C above average for southern Queensland. Similarly, minimum temperatures were above average across most of northern Australia, with isolated parts of southern Northern Territory and southern Queensland more than 4 °C above average.

Fortnightly forecast

The forecast for the fortnight of 18 to 31 October, issued on 13 October, shows rainfall is likely to be above average for parts of northern Western Australia, the Northern Territory and Cape York Peninsula (60% to greater than 80% chance), with the chances being strongest in far northern parts.

Maximum and minimum temperatures are likely to be above average across northern Australia for the fortnight starting 18 October. Days and nights also have an increased chance of being unusually warm across most of northern Australia. Unusually warm temperatures are considered to be those in the warmest 20% of records for this period between 1981 and 2018.

Tropical cyclone season

Tropical cyclone risk increases from November to April, the official tropical cyclone season in the Australian region. At least one tropical cyclone has made landfall on the Australian coast each season since official records began. It only takes one tropical cyclone to significantly impact communities, with potential for damaging winds, heavy rainfall, flooding and storm surge. Tropical lows can also cause substantial impacts, as can tropical cyclones that remain offshore.

Our tropical cyclone season outlook has been updated to include more information about this season, past seasons and future seasons. For more information on preparing for the Australian tropical cyclone season, visit our new Australian tropical cyclone season webpage.

Madden-Julian Oscillation

The Madden–Julian Oscillation (MJO) is currently weak or indiscernible as at 13 October. Most forecasts from surveyed models suggest the MJO is likely to strengthen and re-appear in the Western Hemisphere during the coming week. It is then predicted to track across the Indian Ocean over the coming fortnight. At this time of year, the MJO in these regions typically suppresses rainfall across northern Australia and the Maritime Continent.

International conditions

South-West Monsoon

The South-West Monsoon continues its withdrawal from the Indian subcontinent. As of 13 October, it is close to its climatological position for this time of the year, with further withdrawal of the monsoon from the north-east states currently taking place.

Typhoon Halong

Typhoon Halong formed in the north-west Pacific Ocean as a depression south of Japan on 4 October. The system moved north-westwards towards Japan, reaching typhoon strength on 7 October, developing a clear eye following further intensification. Halong then turned to track north-eastwards on 8 October. Increasing wind shear and drier air caused the system to weaken from 9 October, becoming an extratropical system on 10 October. Halong caused strong waves, wind and heavy rainfall on the Japanese island of Hachijojima, with impacts also felt on the island of Aogashima. The remnants of Halong also had significant impacts in western Alaska as an extratropical system.

Typhoon Nakri (Quedan)

A low-pressure system was identified to the south-east of Guam on 6 October. It gradually strengthened in a favourable environment while tracking north-westwards. It reached tropical storm strength on 8 October, with the name Nakri, before stalling near the Ryuku Islands of Japan. It was upgraded to a severe tropical storm on 12 October and then began to slowly move north-north-eastwards. Nakri strengthened to typhoon intensity on 13 October to the south of Honshu, with the system starting to weaken from 14 October.