Weather in Sydney in April

The month to avoid. Of the twelve, April is the one to avoid. Highs sit at 5.2 °C and the day is short; this is an indoors-with-excursions month, not an outdoors-all-day one.

April ranks 8 of 12 in Sydney: past the worst of the year but short of July, which is the month to book if the dates are open.

Rain on 13 days, 3 of them heavy. Enough to need a plan B, not enough to need a plan around it. Layers, and a genuinely waterproof outer — at 5.2 °C the difference between a good day and a miserable one is entirely down to what you are wearing.

What the averages hide

Averages flatten a month, and this one hides a few things: 18 nights fall below freezing; the day barely swings — 5.6 °C between the overnight low and the afternoon high. Across the twenty years measured, the hottest April day reached 16.9 °C and the coldest night fell to -10.6 °C, and the wettest single day dropped 51 mm — roughly 52% of the month's rain in one day.

April is statistically steady but not small: the year-to-year variation is modest in relative terms, yet the wettest April on record still delivered 181 mm against 51 mm in the driest. In a month this wet, even a tame spread is a lot of rain in absolute terms — the 99 mm average is a reasonable planning figure, not a promise.

Wind sits around 21.9 km/h — a steady breeze rather than a nuisance, and welcome on the warmer days, and humidity runs at 85%, which at 5.2 °C means damp rather than muggy — the kind of cold that gets into a coat and stays there.

How April sits in the year

The month is on the way up: 4.4 °C warmer than March, and May adds another 5.2 °C. Late in the month feels noticeably different from the start of it, which is worth knowing if the trip is short.

Daylight in April

13.5 hours of daylight, gaining 1.6 hours across the month. That is between Sydney's extremes of 15.7 and 8.7 hours, so days are long enough not to constrain the plan.

Sea temperature

The sea sits at about 1 °C in April — too cold to swim without a wetsuit. The sea peaks at 18.4 °C in August and bottoms out at -0.2 °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

Off season. The genuine off season: cheapest by a distance, with the caveat that some tours and restaurants close entirely.

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

April in Sydney versus nearby

If Sydney is one option among several, the nearby comparison is worth making. Halifax is close enough to be a coin toss — within a degree on temperature, the same number of rain days. Moncton is a better bet in April — 4 °C warmer, the same number of rain days.

So: April is a compromise. July is 49 points better and is what Sydney is actually like at its best — worth moving the trip for if that is possible, and worth adjusting expectations for if it is not.

Every month in Sydney

See all twelve months in Sydney, or where else to go in April.