Travellers flying out from Sydney Airport are being warned to expect heavy delays after a thick fog blanketed the city on Monday.

All airlines are experiencing delays, a Sydney Airport spokesperson told www.20304050.best.

“Heavy fog is impacting flights across the network, and we advise passengers to check the status of their flight with their airline,” they said.

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The Bureau of Meteorology reports the patchy morning fog is mainly affecting the city’s west.

But transport across the city has been stalled due to the low visibility conditions.

Sydney ferry services were called off for several hours but have since resumed on the Sydney Harbour and Parramatta River.

“Passengers should continue to allow plenty of extra travel time, listen to announcements and check information displays for service updates as services return to normal,” Transport for NSW said.

A road weather warning was also put in place for drivers across all suburbs on Monday morning.