It's understood that pilot visibility was limited to just 50 metres, due to fog and low-hanging clouds.

Both the QantasLink and Virgin early-morning flights from Tamworth to Sydney were delayed by up to three hours, departing at about 10am, rather than the scheduled 6.30am.

The following Tamworth-Sydney morning flight was also delayed by two hours, departing at 11.30am instead of 9.20am.

The morning flight from the other direction, Sydney to Tamworth, was delayed by three hours, departing at 10am rather than 7am.

With the fog burning off and the low-hanging clouds moving on my midday, the afternoon flights are running as schedule, however airlines are urging all passengers to check the status of their flight.

It followed a damp night in Tamworth, which surprisingly topped the state for rainfall on Monday, with more than 15mm.

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