A developing low pressure system off Australia’s northwest coast has a high chance of becoming a tropical cyclone this weekend.

Two separate areas of low pressure lying off the northern coast of WA are expected to consolidate into one low pressure system by Saturday. This low is likely to gain strength during the weekend as it draws energy from abnormally warm seas sitting off the Pilbara coast.

Image: Enhanced water vapour satellite images showing cloud building around two areas of low pressure to the north of WA on Friday, January 17, 2025.

Forecast models suggest that the low will track towards the west-southwest and build in strength this weekend and early next week, with a high risk that it will become a tropical cyclone on Sunday or Monday.

Most computer models suggest that the soon-to-be tropical cyclone should remain away from the WA coastline between now and at least Monday. However, it could still pass close enough to cause and increase in wind and rain for part of the Pilbara. It’s also important to point out that tropical cyclone movement is notoriously difficult to predict, even more so when the system hasn’t yet formed.

Image: Tropical cyclone likelihood according to the ECMWF ensemble model. The colours show the probability that a tropical cyclone will pass within 300km of a given location within a time window of 48 hours. Source: ECMWF

At this stage, anyone in WA’s Pilbara and Gascoyne regions should pay close attention to the latest forecasts and warnings over the coming days. Details can change frequently with these developing tropical systems.

If this low does develop into a tropical cyclone, it will be the second cyclone to form in the Australian region so far this season, and it will be named Sean.