A cold start to autumn for southeast Australia

As Shakespeare pointed out in his play, Julius Caesar, ‘Beware the Ides of March’. Ides refers to the middle of the month, and that’s when this cold spell began.

I suspect he wasn’t too concerned about overnight frosts on the other side of the world, but that has certainly been the case for parts of southeast Australia recently.

Although it is expected to end soon, this amounts to the coldest start to autumn in more than a decade in some parts of the region.

Temperatures in Victoria have been anywhere up to 10 Celsius below average this month. Melbourne had its coldest March night for seven years on Saturday.

Temperatures have now dipped into single figures on no less than nine occasions this month. The lowest being 7C compared to the March average of 11 degrees.

Meanwhile, some rural parts recorded overnight lows around 4C, which is certainly cold enough for a ground frost.

The cold nights come thanks to a large area of high pressure which led to clear skies and light winds. With no cloud cover to keep the daytime heat in, any remaining warmth radiates away allowing night time temperatures to fall away sharply.

Cricket fans will note that the same clear skies made for perfect cricket weather at the MCG for Sunday’s World Cup final in Melbourne on Sunday. The sun was warm enough to lift the temperature up to 24C.

The temperatures are expected to edge up by day and by night during the week as the high pressure drifts into the Tasman Sea. There will be a pay-off however. It brings the likelihood of cloud and rain by the end of the week.