Weather in Whyalla in September

Prime time. If you get to pick your dates, September is the one. Highs average 21.2 °C, lows 10.6 °C, and rain falls on 5 days — nothing in the month is working against you.

September ranks 3 of 12 in Whyalla. Only October scores clearly higher, and the difference is small enough to be settled by price rather than weather.

Rain falls on only 5 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: it never really gets hot: not one day in an average September reaches 30 °C. Across the twenty years measured, the hottest September day reached 32.4 °C and the coldest night fell to 5.9 °C, and the wettest single day dropped 32 mm — roughly 110% of the month's rain in one day.

This is the volatile part. September rainfall has ranged from 3 mm to 83 mm across the twenty years measured — a 80 mm spread around an average of 29 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 14.6 km/h, so the temperature on the page is close to the temperature on your skin, and humidity is unremarkable at 61%.

How September sits in the year

The month is on the way up: 3.4 °C warmer than August, and October adds another 3.1 °C. Late in the month feels noticeably different from the start of it, which is worth knowing if the trip is short.

Daylight in September

11.8 hours of daylight, gaining 1 hours across the month. That is between Whyalla's extremes of 14.3 and 10 hours, so days are long enough not to constrain the plan.

An inland climate

Despite being inland, the year stays fairly even: 23.7 °C between the year's warmest afternoons and coldest nights.

How busy it gets

Busy. Popular without being frantic; book the things you care about, improvise the rest.

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

September in Whyalla versus nearby

If Whyalla is one option among several, the nearby comparison is worth making. Gawler is close enough to be a coin toss — within a degree on temperature, 3 days more rain. Adelaide is the weaker option in September — 2.6 °C cooler, 4 days more rain.

So: September is effectively as good as it gets here — 4 points behind October, which is inside the margin where the weather stops being the deciding factor and price starts being it.

Every month in Whyalla

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