SINGAPORE: Rains forecast for corn and soybean producing country Argentina and Brazil likely to boost crop development and improve conditions in some areas which have suffered from dry weather resulting from the La Nina weather pattern, this week.

In Argentina, where crops have experienced less-than-normal rainfall this year, the weather outlook calls for scattered showers and thunderstorms of 0.50-1.50 inches on Monday, said Mike Palmerino, forecaster with Telvent DTN weather service.

"A more regular pattern of significant rainfall and no severe heat will favour filling corn and soybeans in the major growing areas," Palmerino said in a report.

Brazil's Rio Grande do Sul, Parana and Mato Grosso are expected to receive regular showers, providing adequate soil moisture to soybeans.

"Generally favourable weather for filling soybeans in the major growing areas with mostly adequate soil moisture," the forecaster said. "The most favourable weather for soybean harvest is expected in the north through mid-week."

Brazil's approaching soybean harvest may surprise markets with a bigger than expected output, despite it being a La Nina year when weather is typically drier over the grain belt here.

Global soy prices have been firming sharply since September last year due to strong Chinese demand and concerns over drought over the South American crops. Argentina has lowered its crop forecasts due to dry weather but Brazil has so far escaped serious losses due to La Nina.

The six-to-ten day weather outlook in the U.S. southern Plains winter wheat area calls for temperatures warming to near-to above normal in the first half of the period with precipitation near-to below normal.

"Further stress to the wheat crop during the outlook period with very warm weather in the past few days being replaced by subzero temperatures this week," said Palmerino.

"Light to moderate snowfall will provide some protection from the subzero cold but not complete protection due to the effects of blowing snow."

The U.S. hard red wheat crop went into dormancy in poor condition, suffering from a lack of rain since the autumn. Wheat continues to deteriorate this winter as dryness persists.