Australia Weather News

Farmers in Western Australia's agricultural heartland are hoping forecast rain this week will make up for a month of unpredictable conditions.

The first major cold front of the year is expected to begin crossing the WA coast on Wednesday, with falls of up to 30 millimetres forecast for some parts of the state's south.

It comes as farmers further inland continue to deal with months without any substantive rainfall.

Scott Crosby runs a 7,000-hectare cropping program in Nyabing, about 320 kilometres south-east of Perth. 

For the past decade, he has begun dry seeding earlier in the year to ensure the year's crop is ready for winter rain.

"Traditionally we were Anzac Day starters and would finish sometime in the first two weeks of June, seeding, on the normal season and if it didn't rain, we'd be finishing later than that," he said.

"Now we're starting seeding in early April or even late March, and have got a lot of the program in before Anzac Day.

"Although it might not have rained, it's there ready for the rain, to go, and if it rains it will come up."

Autumn rain trending down

According to modelling from WA's Department of Primary Industries and Regional Development (DPIRD), the coming weeks could be critical for growers.

Research Officer Ian Foster said May rainfall had trended downward over recent decades amid a changing climate.

"May has, over the last 40-odd years, been declining," Dr Foster said.

"Some wetter Mays, some drier Mays … it is part of a wider context of May, June and July being generally drier."

He said local growers were largely ahead of the trend when it came to adapting to drying conditions, including the earlier starts to seeding.

"A whole range of people are really finding efficiencies in terms of getting crops established and growing early in the season," Dr Foster said.

"It's handy, because it's giving them efficiencies in years like this when we've had a dry start after early summer rain."

He said longer-term modelling indicated favourable conditions for June rainfall in the wake of this week's cold front, followed by a dry July.

"I'd be a bit careful making any definitive statements at what spring looks like," Dr Foster said.

"It'll really depend on what position growers look like in terms of soil moisture at the end of June."

Preparing and staying positive

While the wait for initial rainfall is always tough, Mr Crosby says farmers are now better prepared for the uncertainty.

"First 20 years of my farming career, it was a lot more variable than this," he said.

"We had a couple of major frosts and we had dry seasons, probably the same as what we've had in this last 10 [years]. 

"But because we weren't sowing as early and weren't using the more modern varieties that we've got today they were nowhere near as good."

The 40mm of rain Mr Crosby's property received just before Easter was the first meaningful rain since October last year, and he is banking on good falls in June. 

"I would have loved to have 10, 15, 20mm in May, that would be absolutely perfect, we'd be very happy with that, but we're farming. You've got to be positive," he said.

"We've got to make sure that we're just using what's happening, and trying to make the most out of what's happening."

Despite the drying trend and this year's uncertainty around fertiliser supply and rising fuel costs, WA's growers have planted more than 9 million hectares of crop.