Add Category
It has been a tumultuous five years from drought to plagues to floods, but farmers across southern Australia are about to catch a lucky break — the autumn break to be precise.
Key points:
- The region around Orange and Cowra received about 50mm of rain on Wednesday afternoon
- During the next four days, the eastern half of NSW will see widespread falls of 20 to 50mm
- The upcoming rain event will cut the risk of further major bushfires this season
The phrase is used to describe the first soaking rains of the year after a long, hot, dry summer.
The break is critical to replenish soil moisture before the commencement of winter cropping, and often arrives around Anzac Day, however, in a dry year, it may not arrive until winter, or, in rare circumstances, not at all.
Generally, the earlier the first rains arrive the better for farmers, and while a March break does not guarantee a bumper season, it will lengthen the growing season and increase the potential for high yields, as long as regular rainfall continues through until the spring harvest.
Best rainfalls in months
For some lucky farmers, the best rain since last spring has fallen this week.
On Wednesday afternoon, the region around Orange and Cowra received about 50 millimetres, which is nearly a months' worth of rain.
Benalla in Victoria's north east, has also received 50mm this week.
Gary Amos, a wheat, canola and grain farmer near Cowra in the NSW central west, saw 50mm fall in the past 24 hours, with more expected throughout this afternoon.
"Over the last few months, we have only been getting a few millimetres and this has just set us up for the perfect start to the winter sowing season," he said.
"What we have got over the last 24 hours, that will give us the autumn break and they are also predicting more showers for maybe next week and if that happens well it will be a perfect start for us.
"The last two months have been very dry considering three or four months ago we were swimming, with the hot winds and temperatures things just dried out considerably and with that 50 millilitres it has just kick-started everything
"Perfect world if we could get 10 millimetres every couple of weeks that would be perfect, but it doesn't seem to happen like that anymore."
Where is the rain coming from?
The news of impending rain is welcome, after a dry autumn outlook issued by the Bureau of Meteorology.
So, if La Niña is over, where is the rain coming from?
Sometimes, the weather comes down to good fortune.
Already this week, a near-stationary trough is causing slow-moving showers and thunderstorms across Victoria and NSW.
Troughs are not unusual on the daily weather map, but this one has moisture feeding in from both the east and west, while also sitting under waves of cold air aloft — it's just a good set-up for storms and soaking rain.
What's more of a surprise is what's happening in WA.
Thunderstorms will form off the Pilbara coast during the coming week, and the process of storm development carries moisture vertically into the atmosphere through convection.
Beneficial northerly winds aloft will then carry this moisture to southern states, leading to the formation of the first north-west cloudband of 2023.
A north-west cloudband the metrological name given to broad swathes of cloud that stretch more than 4,000 kilometres across Australia and are responsible for a large proportion of annual rain that falls over inland regions.
How much rain will fall?
During the next four days, the eastern half of NSW will see widespread falls of 20 to 50mm — the heaviest rain in months for some regions.
In the meantime, the north-west cloudband will begin forming across WA, and, by Sunday, will stretch from the Pilbara to the Tasman Sea.
This system could produce more than a month's worth of rain across WA's Wheatbelt and should bring falls of 5 to 30mm to eastern states — enough to constitute an autumn break for regions that receive totals on the higher end of the forecast.
Rain to dampen fire threat
An additional benefit of the upcoming rain event is a dampened risk of further major bushfires this season, except for the unlikely event of a prolonged, unseasonable, mid-autumn spell of hot, dry weather.
The official end to the fire season does not arrive until April for SA, May in Victoria and June in WA, however the overwhelming majority of fire disasters occur during spring and summer.
The NSW fire season ends earlier, at the end of March.