Well done, Brisbane. You've just shivered your way through your first night of the year below 10 degrees.

The temperature in downtown Brisbane dipped to a chilly 8.2°C overnight, with a reading of 7.2°C at the airport and much colder temps inland, including –0.1°C at Kingaroy, which was the Sunshine Coast hinterland town's first subzero night of the year.

The temperature gradient map which you can find on the Weatherzone homepage shows areas of blue (cool air) sneaking a lot further north than usual as the southerlies which have dominated SE Australia since the weekend take a trip north like a planeload of frozen tourists.

Even several inland towns near the Tropic of Capricorn fell perilously close to freezing overnight, including:

• Biloela (just south of the Tropic) had a low of 1.4°C. Interestingly, its minimum on the first day of winter, just three nights ago, was a very mild 17.3°C.
• Clermont (just north of the Tropic and therefore, officially "tropical"!) had a low of 1.1°C. Like Biloela, Clermont's minimum on the first day of winter was exactly 17.3°C.

The good news for all the places mentioned is that daytime temps this week are still heading for tops of 20°C or higher, except for Kingaroy which won't break out of the teens all week.

Brisbane will see tops in the low 20s for the rest of the week with mostly sunny skies. It's a shame the first State of Origin match is at Sydney's Accor Stadium this Wednesday evening, as the forecast for kickoff at Sydney Olympic Park at 8:05 pm is cold and showery.

Weatherzone meteorologist Joel Pippard says there'll be a 40% chance of showers at kickoff, increasing to an 80% chance of rain by the end of the game. Most likely the rain will be light, however there's the chance of moderately heavy rainfall when fans are heading home.