Weather in Katoomba in September

A good month. September is a solid month to be in Katoomba. Highs average 15.9 °C, lows 4.3 °C, and rain falls on 6 days — nothing in the month is working against you.

September ranks 6 of 12 in Katoomba: past the worst of the year but short of October, which is the month to book if the dates are open.

Rain falls on only 6 days, so an itinerary with no wet-weather fallback is a reasonable risk. Pack for 15.9 °C days and 4.3 °C nights; the spread matters more here than any single number.

What the averages hide

The averages here are honest — no hidden extremes worth planning around. Across the twenty years measured, the hottest September day reached 28.1 °C and the coldest night fell to -3.1 °C, and the wettest single day dropped 29 mm — roughly 71% of the month's rain in one day.

September is moderately variable: 1 mm in the driest year against 90 mm in the wettest, around an average of 41 mm. Roughly two Septembers in three land near that average, and the third does something else entirely.

Wind is light at 1.8 km/h, so the temperature on the page is close to the temperature on your skin, and humidity is unremarkable at 67%.

How September sits in the year

The month is on the way up: 4 °C warmer than August, and October adds another 3.7 °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 Katoomba's extremes of 14.4 and 9.9 hours, so days are long enough not to constrain the plan.

An inland climate

With no coast nearby, the year swings a fair way — 26.3 °C between the warmest afternoons and the coldest nights, wider than any coastal city at this latitude would manage. At 991 m the air is thin enough to matter — sun that burns faster than the temperature suggests, and nights that cool off quickly.

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 Katoomba versus nearby

If Katoomba is one option among several, the nearby comparison is worth making. Bathurst is close enough to be a coin toss — within a degree on temperature, the same number of rain days. Sydney is a better bet in September — 3.6 °C warmer, 1 day more rain.

So: September is effectively as good as it gets here — 6 points behind October, which is inside the margin where the weather stops being the deciding factor and price starts being it.

Every month in Katoomba

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