Weather in Port Douglas in September

Prime time. September is about as good as Port Douglas gets. Highs average 27 °C, lows 21.8 °C, and rain falls on 6 days — nothing in the month is working against you.

September ranks 2 of 12 in Port Douglas. Only August scores clearly higher, and the difference is small enough to be settled by price rather than weather.

Rain falls on only 6 days, so an itinerary with no wet-weather fallback is a reasonable risk. Nothing specialised needed — this is the month you pack for the trip rather than for the weather.

What the averages hide

Averages flatten a month, and this one hides a few things: the day barely swings — 5.2 °C between the overnight low and the afternoon high. Across the twenty years measured, the hottest September day reached 33.8 °C and the coldest night fell to 18 °C, and the wettest single day dropped 31 mm — roughly 111% of the month's rain in one day.

This is the volatile part. September rainfall has ranged from 2 mm to 132 mm across the twenty years measured — a 130 mm spread around an average of 28 mm. The average is real but almost no individual September looks like it, so treat the figure as the middle of a wide range rather than a forecast.

Wind is light at 10 km/h, so the temperature on the page is close to the temperature on your skin, and humidity is unremarkable at 73%.

How September sits in the year

Temperatures hold steady either side: 25.5 °C in August, 27 here, 28.4 in October. Nothing about the timing within the month matters much.

Daylight in September

Port Douglas sits close enough to the equator that daylight barely moves all year — 12 hours in September, against a range of just 1.9 hours across the whole calendar. Sunrise and sunset land at roughly the same time whenever you come.

Sea temperature

The sea sits at about 25.2 °C in September — warm enough to stay in as long as you like. The sea peaks at 29.2 °C in February and bottoms out at 24.7 °C — water lags the air by a month or two, which is why the best swimming often comes after the best weather.

How busy it gets

Peak season. Expect the highest prices of the year and to be booking well ahead.

Crowd levels are estimated from climate desirability and school-holiday calendars, not from visitor numbers.

September in Port Douglas versus nearby

If Port Douglas is one option among several, the nearby comparison is worth making. Cairns is the weaker option in September — 2 °C warmer, the same number of rain days. Townsville is close enough to be a coin toss — 2.8 °C warmer, 4 days less rain.

So: September is effectively as good as it gets here — 1 points behind August, which is inside the margin where the weather stops being the deciding factor and price starts being it.

Every month in Port Douglas

See all twelve months in Port Douglas, or where else to go in September.