Forecasts for rains eased fears for dryness affecting Brazil's next soybean crop too, coming on the eve of the start of what is expected to be a record planting season.

"The Brazil weather forecasts have now added rain for Mato Grasso and northern Brazil during the last half of September," US Commodities said.

"This would be timely. Rain is needed to get soybean planting under way."

Closely-followed crop scout Michael Cordonnier, at Soybean and Corn Advisor, said that the forecast of showers "late next week in Mato Grosso", Brazil's top soybean state.

"Now we will have to wait and see if they materialise or not."

Just in time

Rains would be well-timed, with a state-enforced 90-day soybean-free period in central Brazil expiring on September 15, which thus marks the opening of the soybean window.

However, the sowing concerns are not over, given the extent of the current dryness in the region, pat of which have gone some 115-120 days without precipitation.

"That is not so unusual. It often does not rain between the end of the rainy season in May until September," Dr Cordonnier said.

Hottest month

But what it means is that growers need significant rains before embarking on sowings.

"If Mato Grosso gets two inches of rain, farmers will go ahead and plant. But if it is half an inch, it depends what it is in the forecast.

"What farmers do not want is to go ahead and plant and there to be no follow-up rains, meaning plants germinate, but do not develop and have to be resown."

September is the hottest month in central Brazil, and with temperatures currently hotter than normal, at some 39-41 degrees Celsius.

First harvester advantage

A delay in sowings would not be a threat to hopes of the country reaping a record crop, which many analysts, including Dr Cordonnier, see topping 80m tonnes.

"If sowing gets delayed a couple of weeks, it does not matter for the yield.

"But what it will do is delay the harvesting of the crop the other end," hurting importers which are struggling for supplies after drought-hit South American and US crops, and are relying on Brazil having shipments available from around the end of January.

Indeed, farmers are so keen to attempt to tap this early demand, which promises higher prices than later-harvested crop, that Brazil is sold out of seed for early-maturing varieties, he said.

An early harvest also improves farmers' scope for planting a follow-on corn crop, so exploiting high prices of the grain as well.