Tropical Outlook


G'day everyone

After the driest start to the wet season in 27 years for Darwin, A weak monsoon trough has developed and looks to arrive in the next three days. So far this wet season, Darwin Airport has recorded 439mm of rain in the gauge from October 1st until 9 am January 20th. On average during this period, Darwin sees 719mm, making it the driest start to the wet season since 1992.

In Western Australia’s Kimberley, it has also been a dry start. While in the wet season to date, Wyndham would usually have 355mm recorded, they have only recorded 236mm. Falls this low have only happened twice before in the last 40 years, in 2012 (196mm) and in 2003 (95mm).

Synoptic Chart


However, while the Northern Territory and Western Australia have failed to see any good rainfall this season so far. The tropical North in Queensland imparticular Cairns and the surrounding Queensland Coast have enjoyed a very wet start. Cairns has recorded 953mm so far this wet season, compared to an average of 582mm. This makes it their wettest start in 10 years.

Now a weak monsoon has developed north of Australia over the weekend and will slowly edge its way south and east, most likely arriving around Tuesday or Wednesday. The latest the monsoon trough has ever arrived was January 25th in 1973, making this year one of the latest monsoon onsets on record.

Synoptics for the tropics

Synoptics for the tropics


A weak tropical low developing monsoon trough, about 190km east of Thursday Island. The system is expected to slowly intensify and track either towards the southwest or southeast over the next few days. Conditions are expected to become more favorable from Thursday and as a result, the potential for tropical cyclone development in either the Gulf of Carpentaria or the northwestern Coral Sea will increase.

Another weak tropical low in the Coral Sea, near 11.8S 158.4E. Atmospheric conditions are not favorable for significant development over the next three days.

Possible Tracks

Possible rainfall if it takes the more eastern track


This also a weak tropical low which has developed in the Monsoon trough well north of the Northern Territory in the in the Arafura Sea. It is also forecast to move generally southwest towards the Timor Sea over the next week, with the risk of it developing into a tropical cyclone increasing later in the week. The system could move close to the Kimberley midweek and then possibly near the Pilbara later in the week.

Also, tropical low (11U) is still alive and is located about 100 km west of the Cocos Islands. The system is forecast to continue moving westwards, with a small chance of reaching tropical cyclone intensity from Tuesday. It should be well clear of the Cocos Islands by this time. It is likely the system will move out of the Australian region of responsibility on Wednesday.

So there is an increased chance of tropical cyclones to develop over the Australian waters with the arrival of a weak monsoon and an increasing MJO. It is important if you live in the tropical north to be prepared and to stay up to date with the latest outlooks issued by the Bureau of Meteorology.


Gradient wind analysis