Two tropical cyclones are interacting off the northwest coast of Western Australia, prompting warnings to holiday-makers.
Tropical Cyclone Seroja is tracking southwest at 23km/h and was 525km northwest of Exmouth in the early hours of Friday.
It is expected to make landfall late Sunday or early Monday between Carnarvon and Jurien Bay.
The Bureau of Meteorology says it has begun to interact with another system, Tropical Cyclone Odette, located northwest of Seroja.
This rare event is known as the Fujiwhara Effect.
"Tropical Cyclone Odette is only expected to be a short-lived system as it is likely to weaken during its interaction with Tropical Cyclone Seroja over the weekend," the bureau said on Friday.
"By Sunday, the system is likely to have weakened over waters west of the Gascoyne coast."
A severe weather warning is in place for the west Pilbara and northwest Gascoyne.
Damaging winds with gusts in excess of 90km/h could develop between Exmouth and Carnarvon on Saturday.
Seroja is expected to intensify to a category two or three cyclone over the weekend.
A cyclone advice alert has been issued by the Department of Fire and Emergency Services for people in or near Coral Bay to Geraldton in the Gascoyne and Mid West regions.
Acting DFES commissioner Craig Waters said there were many holiday-makers in the area, many of whom would not have experienced a cyclone before.
"Recent rainfall and flooding has already battered the northern half of WA during the current cyclone season," he said.
"If you're in a tent or caravan, you are simply not protected against the damaging winds that may hit the region.
"Some roads in the area are still undergoing maintenance to repair damage from recent flooding events and Tropical Cyclone Seroja has the potential to cause further damage making roads unpassable for days, if not longer."
The DFES is urging travellers to reconsider their plans and stay up to date with the latest emergency information.
"The size of this potential impact area is another reason to be prepared, because you may need to travel some distance before you are out of harm's way," Mr Waters said.