The winter that never was, no longer is. Although officially, spring will not commence until this Sunday (September 1st), three weeks ahead of the spring equinox.
The 2013 winter will go in the annal books as an unseasonably warm winter across not only southeastern Australia but for the whole country with very few cold spells throughout the June-to-August period. This winter will probably be in the top three warmest on records, if not the warmest.
Temperatures have been particularly warm due to a stronger than average subtropical ridge across central areas of the continent. This has led to clear skies and plenty of sunshine to warm up the central interior. The subtropical ridge has also been further south than usual, preventing cold fronts reaching the southern states from polar regions.
Although we have had some cold fronts marching through southern Australia this winter, drawing the warm air south with northerly winds ahead of them, they have also been weaker than usual. The cold air behind these front have been generally not as cold or long lived, to flush the heat away from the landmass.
Sea surface temperatures surrounding the country have also been warmer than usual, as there has been plenty of sunshine to warm the ocean surface around Australia. Warmer than usual onshore winds have therefore added to the warming effect.
In fact, the past 12 months have all been abnormally warm, a feature that started in September 2012 and which led to Australia's hottest day on record, hottest summer on record and hottest September-to-June on record. And this hasn't discriminated between rural or urban areas, as everyone has been the subject of the mercury rising.
For those now thinking how September is shaping up, or how the spring and summer will end up being, I must emphasis that there is no way of forecasting the day-to-day temperatures so far in advance, and summer is still three to six months ahead.
We do live in a country of extremes or as Dorothea Mackellar wrote back in 1908 '... a land of droughts and flooding rains'. As such its not going to be long before we get to see 30 degree days in the south and even 40 degrees across the north. The fact is, extremes are intrinsic to our country and the next two weeks will seem particularly warm.
Looking at the trend of the past 11 months and bearing in mind that climate drivers like the El Nino-Southern Oscillation are most likely to remain neutral, temperatures will be on the warmer side of the long term norm. In fact, if the last four months of 2013 follow the trend of what happened over the last four months of the past 10 years, we will most likely end up very much on the warm side of the balance. A balance that could see 2013 as one of, if not the warmest on record.
© Weatherzone 2013
13:56 EDT Like a large area of southeastern Australia, Victoria has been been experiencing a chilly run, as much as four-to-ten degrees below average but is now thawing out.