Parts of northern New South Wales awoke this morning shrouded in fog. As residents of the New South Wales Northern Rivers and Mid-North Coast went to sleep last night, conditions were stable, balmy and pleasant. As the night progressed, the temperature dropped far enough for atmospheric moisture to condense and linger under light to calm winds. As the sun peaked over the horizon just before six o'clock this morning, the relative humidity at Grafton peaked at 96%, resulting in fog restricting visibility to less than 100 metres. Along the coast, the fog was not quite as thick with visibility restricted to 500 metres at Ballina and 600 metres at Port Macquarie. This fog rapidly dissipated as northerly winds picked up just before eight o'clock. Further west at Tabulam, the sea breeze failed penetrate far enough inland allowing the fog to linger slightly longer. By nine o'clock, visibility was still as low as 800 metres before rapidly burning off with temperature reaching 31 degrees by midday. The arrival of a low pressure trough this evening is set to ruin any chances of fog developing in the near future with Sunday seeing the next best chance with lingering moisture and easing winds.