Vejret i Kangaroo Island (Kingscote) i september

Adelaide forum regulars call September genuinely unpredictable — seasons arrive late here, so it can still be a little cool with often spring showers and sunny days, swinging between “cold with a wind chill factor” and “balmy with spring storms and humid temperatures” depending on the week. Typical readings run “17 and 25°C” by day but can drop “as low as 7 degrees” overnight. A light, hooded waterproof jacket is the standard packing recommendation for the showers that show up without much warning. The OzAsia Festival (from September 17) and the weekly Sunday farmers market at the Showgrounds are the events regulars point to regardless of what the sky does. Our record: 17.4°C days, 10.4°C nights, 9.4 rain days and a 24.8kph wind — mild with genuine variability and real wind, matching the “unpredictable, showers and sun both” read.

Regulars are specific this falls within the lightest-wind stretch of the year here, April through June, early-month visitors commonly reporting comfortable low-20s temperatures and plenty of sunshine even as evenings turn genuinely chilly. Our row backs that mild, genuinely dry read, 21.6C over 11.1C nights feeling 9C, with rain minimal at 22.5mm across 4.3 days and a real 20.2 kph wind. Regulars are consistent golden autumn sunsets are a real late-afternoon highlight this time of year, sea conditions staying genuinely calm and benign for anyone planning boat trips or coastal walks. This remains one of the better windows to visit overall. The sea sits at a mild 18.5C. The record: 9.1 hours of sun, humidity 70 percent and AQI 25.

Spring here is warm with occasional cool days and scattered rain, mostly fine, mid-twenties with the odd hotter day - which our row backs almost exactly at 21.8C reading as 21C, with 25.8mm across 5.2 days. The wildlife and the wildflowers are both at their best now, regulars say, more out and about than any other season. The one constant they will not let a visitor forget is the wind - cool, sometimes cold, off the ocean at any time of year, with southeasterlies typical from November through March - and our column carries a real 23.4 kph average. The sea is 16.8C, cool enough to be a look-don't-swim proposition for most. The record: humidity 67 percent, 11.7 hours of sun and AQI 28.

Regulars set expectations downward for December and are right to: not cold by northern standards, but not especially hot either, and nobody comes here to sunbathe. Wind is the constant - cool or cold off the ocean at any time of year, with south-easterlies usual from November through March and the calmest stretch falling in April to June. Our row measures it at 23.4 kph against 24.4C days that drop to 11.9C at night, and puts the sea at 17.9C, which settles the swimming question. What the month does offer is dry, bright weather for the wildlife: 22.8mm across 3.7 days and 12.3 hours of sun inside 14.5 of daylight. The record: humidity 66 percent and AQI 27.

January is the busy month and the hot one - South Australians put the worst of the heat in late January and early February, and warn that away from a sea breeze the island bakes like the mainland during a heatwave. Our row's 25.7C monthly average is the Southern Ocean doing its work most days; the heatwave is what the average hides. The advice that actually changes a trip is about wildlife, which is the reason most people come: in midsummer the animals are largely nocturnal, so dawn and dusk are when you see them and the middle of the day is when you do not. South-easterlies run November to March, which our 23 kph reflects. The record: 14.2C nights, 21.4mm across 3.4 precipitation days, 12 hours of sun, a 19.6C sea and AQI 27.