Mr Knowles was not in the habit of driving great distances but he is described as a cautious driver and normally very organised - "a creature of habit".
He was driving a baby blue coloured 1996 Honda Accord LXI Auto saloon registration number UN1109.
He was possibly wearing brown trousers, a shirt and running shoes.
There are concerns for his safety as his family has not seen or heard from him since he left Katikati yesterday. This is out of character.
If you have any information on Mr Knowles whereabouts, and for any sightings of him or his vehicle, please contact police by calling 111 (quote reference number P013275864).