Australia’s Port Hedland, the world’s largest bulk-export terminal, handles cargoes for BHP, Roy hill, and Fortescue Metals .

A tropical cyclone has formed off Western Australia and is expected to cross the coast on Friday, bringing heavy rain and damaging wind gusts to the nation’s major iron ore export hub.

Cyclone Zelia is expected to strengthen as it moves toward the Pilbara coast, with the slow movement of the system likely to produce very high rainfall along its track, according to the Bureau of Meteorology. The storm is currently a Category 1 and could intensify to a Category 3 before making landfall.

A series of cyclones have dumped heavy rain across the Pilbara region this year and disrupted iron ore operations, even damaging a port facility operated by mining heavyweight Rio Tinto Group. Further downpours on already saturated ground could lead to flash flooding and put vital rail links to ports at risk.

Zelia is set to be the first tropical storm to cross the Australian coast this cyclone season, which runs from November through to the end of April. The system is currently forecast to make landfall near Port Hedland, Australia’s biggest iron ore export port, which is scheduled to clear all the ships from its harbor on Wednesday.