By Ana Mano and Roberto Samora

SAO PAULO (Reuters) -Torrential rainfall in Brazil’s second-largest soybean and sixth-largest corn state is disrupting the final stages of the harvest, according to a meteorologist’s bulletin on Thursday, a grains broker and an analyst.

Historically, soy farmers in Rio Grande do Sul would have harvested 83% of the area at this time, but the heavy downpours have disrupted the work, according to state crop agency Emater.

Still, the soybean harvest in the state had reached 76% of the planted area by Thursday, an increase of 10 percentage points compared with the previous week, Emater said in its weekly crop report.

As heavy flooding hit Southern Brazil, Chicago soybeans jumped to their highest point in more than three weeks.

“Torrential rains in Rio Grande do Sul have already caused numerous disruptions and losses,” said Marco dos Santos, a Rural Clima meteorologist. Santos cited losses in soybean, corn and rice areas.

The heavy rains, which will likely continue through the weekend, with a respite between Sunday and Monday, have brought flooding to rural and urban areas, blocking roads and destroying infrastructure.

A new cold front should bring more rainfall to Rio Grande do Sul starting on May 9, Santos said. He noted that lower amounts of rain are expected when that system forms, but added that any rain on extremely wet soil “is chaos.”

In the south of Rio Grande do Sul, an estimated 40% of the soybean crop remains to be harvested, the broker said. In the north, around 80% to 90% has been harvested, he added.

Santos said it will continue to rain in much of the northern section of Rio Grande do Sul, as well as the in south of neighboring Santa Catarina.

“These very voluminous rains, with no sunny breaks to harvest (grains), always end up causing quality losses,” said Adriano Gomes, a grains analyst at consultancy AgRural.

Rio Grande do Sul was expected to produce 68% more soybeans this season than last, according to estimates from national crop agency Conab for Brazil’s No. 2 producer after Mato Grosso state. Emater projects a record crop of 22.25 million metric tons, up 71.5% from a year ago.

The rains have killed at least 13 people, while 21 are missing, according to local authorities.

On Wednesday, a national holiday in Brazil, the state government warned the situation was critical and could deteriorate further.

Some 83% of the corn area has been reaped in Rio Grande do Sul as of Thursday, a 1 percent rise from the same time last week, according to Emater data.

(Reporting by Ana Mano and Roberto Samora in Sao PauloAdditional reporting by Eduardo Simoes; Editing by Bernadette Baum, Jonathan Oatis and Matthew Lewis)

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