It was another foggy start to the day for Queensland's Capricornia but a cold front means that chilly and clear nights are on the way. A cold front approached central QLD on Monday, with warm northerly winds ahead of it leading to a hot and humid day. Rockhampton hit a toasty 30 degrees, five above average and the hottest day since April. A little further south, Gladstone reached 28 degrees, four above average. After some light morning showers, winds turned to the northeast, dragging moisture in from over the ocean and increasing the humidity. As the mercury dropped after sunset the relative humidity rose further, reaching 100% by 5am as fog formed across the Beef Capital. By 6:30am visibility had dropped to 50 metres, making for an eerie start for early risers. Fog was a feature across the Capricornia, with visibility lowering to about 400m in Gladstone. Further afield, Bundaberg also dropped to 400m, with 300m at Prosperpine and 150m up at Townsville. Locals will have become used to foggy mornings, after waking up to gloomy skies several times this week. The fog was quick to lift as a cold front crossed during Tuesday morning, accompanied by dry southwesterly winds. At Rockhampton, the winds arrived not long after sunrise, causing the relative humidity to tumble from 99% to 50% between 8 and 9am. Accordingly, the fog lifted quickly, making way for a mostly sunny day. In the wake of the front, a cool airmass will linger bringing chilly nights but dry winds should keep any fog at bay. It will cool near or below 10 degrees each night until at least Saturday. Wednesday night/Thursday morning will be the coldest, dipping to seven degrees in Rocky, six in Gladstone and below freezing around Biloela. If it cools that much in Gladstone, it will be the coldest night since 1995. By early next week, nights will warm again as the airmass heats up and easterly winds bring some cloud and possible showers.