Weather in Warrnambool in December

Prime time. If you get to pick your dates, December is the one. Highs average 19.2 °C, lows 13.4 °C, and rain falls on 9 days — nothing in the month is working against you.

December ranks 4 of 12 in Warrnambool: past the worst of the year but short of January, which is the month to book if the dates are open.

Rain on 9 days, 1 of them heavy. Enough to need a plan B, not enough to need a plan around it. 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 — 5.7 °C between the overnight low and the afternoon high. Across the twenty years measured, the hottest December day reached 34.7 °C and the coldest night fell to 10.4 °C, and the wettest single day dropped 54 mm — roughly 100% of the month's rain in one day.

December is moderately variable: 15 mm in the driest year against 124 mm in the wettest, around an average of 54 mm. Roughly two Decembers in three land near that average, and the third does something else entirely.

Wind sits around 18.5 km/h — a steady breeze rather than a nuisance, and welcome on the warmer days, and humidity is unremarkable at 74%.

How December sits in the year

Temperatures hold steady either side: 17.8 °C in November, 19.2 here, 20.7 in January. Nothing about the timing within the month matters much.

Daylight in December

December is at or near the longest days of Warrnambool's year: 14.8 hours of daylight, holding steady all month. Evenings are the real gain — dinner outdoors still happens in full light.

Sea temperature

The sea sits at about 15.9 °C in December — cold — a quick dip rather than a swim, and a wetsuit if you are in for longer. The sea peaks at 17.9 °C in February and bottoms out at 13.6 °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.

December in Warrnambool versus nearby

If Warrnambool is one option among several, the nearby comparison is worth making. Ballarat is close enough to be a coin toss — 5.8 °C warmer, 2 days less rain. Mount Gambier is close enough to be a coin toss — within a degree on temperature, 1 day less rain.

So: December works, with January the better month by 9 points if the dates can move. If they cannot, nothing here should stop you booking.

Every month in Warrnambool

See all twelve months in Warrnambool, or where else to go in December.