A thick fog in Melbourne is causing problems for Sydney-siders heading to Melbourne as flights along one of Australia's busiest routes clog up and cause delays.
The low-lying cloud of fog settled over Melbourne has affected both domestic and international flights.
Despite delays of up to 30 minutes, all scheduled flights from Sydney to Melbourne have since taken off but some are facing delays in landing.
A spokeswoman for Qantas said flights are leaving Sydney as scheduled but circling Melbourne in a holding pattern for up to half an hour.
“There is some congestion and several of our flights are in a holding pattern,” she said.
A spokeswoman for Virgin Airlines said there had been delays of up to 30 minutes for Melbourne-bound flights from Sydney.
“We have had to cancel five return flights out of Melbourne, but those passengers will be reaccommodated onto later flights.”
Sydney will also be fielding several international flights diverted from Melbourne.
Melbourne Airport spokeswoman Anna Gillett said two dozen domestic flights had been disrupted and QF94, from Los Angeles to Melbourne, was diverted to Sydney.
She said if there was any break in the fog planes were ready to take off.
Scott Williams, senior forecaster at the Bureau of Meteorology, said visibility was expected to be down to about 200 metres.
"We're expecting the visibility to improve there around 9am, lifting from quite low visibility to somewhere around 2km or better. That's the sort of critical value for the incoming aircraft. It'll lift to cloud at about 500 feet later this morning, but it may not improve beyond 1000 feet."
The visibility issues should affect flights until about 9.30am as the cloud base is so close to the ground, making landing difficult.
More to come.