Tropical Climate Update

Fortnightly rainfall exceeds May average across parts of northern Australia

May is the first month of the northern Australia's dry season, which runs through to the end of September and is characterised by generally low rainfall totals. Despite the arrival of the dry season, multiple weather features have tapped into tropical moisture remaining just to the north of Australia, which has led to a wetter-than-average fortnight across northern Australia, including some locations that have well exceeded their average for May. The average May rainfall for most of northern Australia is between 5 and 25 mm, except along Queensland's north tropical coast, where monthly average rainfall is 50 to 200 mm in some areas.

The fortnight ending 18 May saw rainfall totals between 25 to 100 mm, and locally higher, across the Kimberley, Western Australia, parts of the north-eastern Top End, Northern Territory and eastern coast of the Peninsula, Queensland. May rainfall totals to date are above average across most of Western Australia's Kimberley region, most of the Northern Territory, except for the Top End, and much of western Queensland. Mean maximum and minimum temperatures are tracking above average across most of the tropical north so far for May.

Madden–Julian Oscillation in the Indian Ocean

The Madden–Julian Oscillation (MJO) is currently indiscernible. Most models forecast the MJO to strengthen in the Western Hemisphere region over the next fortnight. If this occurs, associated westerly wind anomalies over the western Pacific could support further El Niño development

Indian monsoon onset forecast to be earlier than usual

Onset of the annual Southwest Monsoon is expected to occur in the coming weeks, several days ahead of its typical onset date of 1 June. The official onset date is declared when the monsoon reaches far southern Indian state of Kerala. The northernmost extent of the monsoon is currently further north than usual for this time of year. For updates on India's Southwest Monsoon onset, refer to the Monsoon Information Onset | India Meteorological Department.