Melbourne in January averages a high around 26-28°C and a low around 15°C, with humidity that swings anywhere from 44% to 65% depending on the day. Those numbers describe an average day. They say nothing about what Melbourne is actually known for: the city sits close enough to the path of cold westerly fronts that it can genuinely run through four seasons in a single afternoon, and during the Australian Open that's not folklore, it's a real planning problem. A 35°C morning can drop 15 degrees by evening when a southerly change rolls through, sometimes with almost no warning.
Outside the three roofed arenas, there's very little shade anywhere on the grounds. That makes sun protection a real logistics item, not an afterthought — sunscreen and a hat aren't optional accessories here, they're closer to required equipment for a full day outdoors. Fabric matters more than most people expect too: linen, lightweight cotton, and moisture-wicking blends handle a 30°C day session meaningfully better than denim or synthetic fabrics, which trap heat against skin for hours at a time.
The temperature swing cuts both ways, which is the part visitors from genuinely hot climates tend to underestimate. Bring a light jacket or jumper even in the height of summer — an evening session after a cool change can be uncomfortably chilly in just a t-shirt, especially once you're sitting still for three hours rather than moving around the grounds. Comfortable shoes matter just as much as temperature-appropriate clothing: Melbourne Park is a genuinely large precinct, and a day of court-hopping on a grounds pass covers real distance.
If you land without the right gear, Melbourne Park runs a pop-up Chemist Warehouse on-site during the tournament, along with vendors selling hats and sun gear directly on the grounds — a real, practical safety net if the weather does something your suitcase wasn't packed for.
The wider seasonal pattern is worth understanding too: Melbourne's January sits inside a summer that technically runs December through March, and the city's exposure to shifting westerly wind patterns is what drives the day-to-day unpredictability rather than any single unusual year. That's not a warning about an unusually bad tournament coming up, it's simply how Melbourne's climate behaves most Januaries, tournament or not — which is exactly why the packing advice here holds regardless of what any single week's forecast says closer to the date.
Humidity is the other variable worth planning around, separate from raw temperature. Melbourne's January humidity swings between roughly 44% and 65% depending on the day, and a 27°C day at the higher end of that range feels noticeably heavier than the same temperature on a dry day — worth factoring in alongside the raw forecast number rather than judging comfort by temperature alone.
