News

Spring see-saw brings wildly fluctuating temperatures in southeastern Australia

Maximums in several southern capital cities will bounce up and down by as much as 15 degrees this week, as spells of summery and wintry weather jostle for dominance.

After a maximum of just 16.8°C on Sunday, Adelaide will hit the high-20s midweek, drop back to a top of just 20°C on Friday, then likely soar up 32°C on Sunday.

Melbourne is heading for just 17°C this Monday but should reach 30°C by Thursday, before maximums drop back into the teens late in the working week ahead of more warmth due on Sunday.

After almost reaching 32°C in the city yesterday (Sunday), Sydney will see more moderate peaks in the mid-20s midweek, before again heating up significantly to 32°C on Friday. Expect a much cooler maximum of 21°C on Saturday.

Hobart has edged its way towards its predicted maximum of 15°C this Monday. The Tasmanian capital should warm quickly to 27°C by Thursday before dropping straight back to a high of just 16°C on Friday. By Sunday, maximums will again be in the mid-20s.

It’s also worth noting that Hobart’s overnight low was just 4°C, while high above the city on the summit of kunanyi/Mt Wellington, the mercury fell to -4.1°C. In the tiny town of Liawenee on Tasmania’s Central Plateau, last night’s minimum of -6.2°C was the coldest night anywhere in Australia to date this October.

Image: Thursday will be one of the warm days this week across most of the southeast. 

Why the spring see-saw?

This week's strong temperature fluctuations are being caused by a series of cold fronts clipping the southern mainland – interspersed with bursts of warm air being dragged southwards from Australia’s interior.

Brief spells of mild conditions which many people would consider "typical" of spring will punctuate the temperature extremes. But the reality of spring weather in southern Australia is that variability is just as common as a run of days when maximums are consistently mild.

As for the other capitals:

Brisbane can expect only slight variations in its maximums, which will range between about 26°C and 30°C all week.

Canberra should also see less variation than cities like Sydney and Melbourne, with maximums in the 20s all week. The national capital is too far north for the coolest air from this week’s spring cold fronts, but high enough above sea level to prevent temperatures reaching the 30s as they will in Sydney and on the nearby NSW South Coast.

Perth will also see maximum temperatures hovering consistently around the mid-20s, although a cool change is due by Sunday as a cold front clips the southwest.

Darwin will be hot, which will be no surprise to anyone, but it’s worth noting that our northernmost capital city’s hottest two months are October and November as heat builds up before the wet season fully kicks in. The average maximum in both months is 33.4°C, but this week you can expect 35°C most days.