Tropical Climate Update

Two tropical cyclones in the Australian region

Severe tropical cyclone Marian (category 4 intensity) lies over open waters of the southern Indian Ocean, in the far west of Australia's tropical cyclone area of responsibility. Marian has maximum sustained winds of 165 km/h and is forecast to weaken marginally and move in a south-easterly direction in the coming days, remaining well west of the Western Australia coast.

Tropical cyclone Niran developed on 2 March, just off the north tropical coast of Queensland, and is currently classified as a category 2 storm with maximum sustained winds of 95 km/h. Niran is expected to remain slow-moving for the next 2 or 3 days before moving east away from the Queensland coast later in the week. Current forecasts indicate Niran could reach category 3 strength as it passes near to Willis Island in the Coral Sea. At this stage, it is not expected to directly impact the Australian mainland.

Read more about latest Australian tropical cyclone outlook and warning information

Rain in the east, monsoon break elsewhere

Widespread rainfall is forecast to be mostly confined to far north Queensland in the coming week, with the remainder of northern Australia expecting low to moderate rainfall. However, parts of Western Australia may see weather conditions become conducive to significant rainfall during the next few days.

Near and east of tropical cyclone Niran, off Queensland's north tropical coast, active monsoon conditions are apparent, but further west, monsoon break conditions will become established across northern Australia, leading to a period of isolated shower and thunderstorm activity. Depending on the position and movement of tropical cyclone Niran, parts of coastal north-eastern Queensland could see some high rainfall totals before the predicted eastwards track steers the cyclone away from the east coast and into the Coral Sea.

Madden–Julian Oscillation is weak

The Madden–Julian Oscillation (MJO) is currently weak and indiscernible. Equatorial Rossby (ER) wave activity remains the dominant type of tropical atmospheric wave in the Australian region. An ER wave tracked westwards across Australian longitudes last week, contributing to significant tropical low and rainfall activity across the region, and providing conditions favourable for the formation of tropical cyclone Marian. The focus of ER wave activity this week is currently around western Pacific Ocean longitudes, but is expected to track further west in the coming days before weakening.

Climate models indicate a pulse of the MJO is expected to develop and move east over the tropical Americas and Africa in the coming fortnight. At this time of the year, an MJO pulse in these regions is typically associated with below-average rainfall across northern Australia and the Maritime Continent. The Bureau's current rainfall outlook reflects this with below-average rainfall expected across much of the Northern Territory and northern Western Australia during the first half of March.

Read more about the Madden–Julian Oscillation