The 2009-2010 summer so far in Eastern Australia has simply been bizarre.

If I were a grape I would even think it odd. The expected routines of past decades have simply now been debunked because seasonal predictions just fail.

Clearly this is climate change, but change from what? Maybe this was how things went on a century ago or five centuries ago and we don’t have the historical records to understand it.

And if climate is cyclical as a meteorologist will tell us then such events have occurred before when grape vines were not so intensely studied in the grape growing regions of New South Wales and Queensland.

Spring started cool as we expect, but then October brought incessant 40C heat waves (southern Australian regions called “cool” just fried), the stuff that normally comes in January-February. Coupled with that was the grip from El Nino meaning a summer drought was to occur.

It did, and with a bite so that some summer rainfall regions received a paltry 15mm over the three months; September-November. Some even experienced the same drought extending into mid-December before a storm landed. It’s not funny when daily evaporation is 10mm so that the vine soil dries out badly.

To rub it in four dust storms originating in Alice Springs blew in through October dumping tonnes of their red dirt. Vineyard leaves were top dressed!

On top of that came the November chill-frosts in a wave a week apart which turned green leaves black in the high-altitude vineyards along the Great Dividing Range-Stanthorpe to Orange.

An eastern Australian summer routine used to be driven by the south easterlies – they drove the scuds of moist air and cooling breezes from sea to land each afternoon. These have virtually stopped.

The “wet” in North Queensland started late (end December) and not one cyclone has yet formed.

The main influence all December running into January has been an ex-WA cyclone which turned into a rain depression which then dawdled across central Australia for three weeks. It spawned both upper and lower inland troughs which have gently sprinkled rain throughout the dry dead centre (Ayers Rocks in spray formation).

Rains have saturated north west NSW, central western Queensland and kicked off the wet in the gulf country. The upper Darling River is flowing for the second time in two decades.

The infamous Lake Eyre is filling: it could challenge its maximum depth of six metres (the last big fill in 1990 reached just 1.5 m).

As vintage starts in the South Burnett, western Downs and central western NSW the conditions are cool, caused by cloudy weather from the central Australian rain depressions. Although overcast, the big rains have not come and the first verdelho harvests have been superb.

In future there is no point relying on a steady summer rainfall – it will never exist until the cycle clears itself, perhaps in another century or so.