helmet + clothes - wet weather gear
OK, so Australia is going through a 7 year drought. When the old weather patterns will return is not clear.
Around the coast it rains a bit. The Great Ocean Road in Victoria and south west Western Australia get hit by regular cold fronts at any time of the year. A day or two of showers and then some respite. Until the next one hits.
Rain together with usual strong winds means it’s cold on the bike. You can try and wait out the worst of it. A decent rain jacket is a good investment. Not to keep you dry so much as to block some of the wind.
When you head inland the weather pattern changes. Long, long fine periods. Any rain tends to be short heavy downfalls. It’s rare to have lengthy drizzily days. Much more common to be worrying about lightning strike from the usually dry thunderstorms. Plenty of massive thunder booms like the Third World War has just broken out.
Head up north during the winter and you hit the Dry Season. Day after day of fine weather with little chance of rain. Why would you be anywhere else?
But the Wet Season up north?
Forget it. The chance of widespread flooding. Extreme humidity. Massive thunderstorms.
As for wet weather gear, a decent coat is useful, and in the south during winter a pair of gloves, but unless you are attempting Tassie in winter you might as well take your chances.