OMAHA (DTN) -- Argentina's soybean crop might not be as strong this year as the presence of an El Nino would normally suggest.

The large-scale weather feature known as El Nino in the equatorial Pacific -- a feature characterized by warmer-than-normal temperatures and a west-to-east subtropical jet stream component -- promises to be in effect from now through the first quarter of 2010. That time frame covers the Southern Hemisphere summer season, which includes the key development time frame for row crops in South America.

El Nino is usually a rainmaker for Argentina and southern Brazil. U.S. Climate Prediction Center analysis of worldwide effects of El Nino during the December-January-February time frame prominently features the eastern half of Argentina through Uruguay. The center also focuses on the second- and third-largest soybean production states of Brazil -- Parana and Rio Grande do Sul -- as a region with "wet" weather conditions relative to normal.

But DTN Ag Meteorologist Mike Palmerino isn't buying into the "usual" El Nino outlook just yet -- especially for Argentina.

"Brazil will do well. Their weather pattern has already been wet, and El Nino through the summer growing season will be wet as well," Palmerino said. "To me, the real question mark is Argentina. My problem there is that I want it to be wetter, but we are seeing somewhat of a lingering of the old drought pattern featuring more west and southwest flow aloft, which is drier."

DRY PATTERN WAS DISASTROUS

The dry pattern in the 2008-09 crop season was disastrous for Argentina's soybean crop. The final '08-09 harvest totaled just 32 million metric tons, almost one-third less than the 46.2 million tons harvested in 2007-08.

As the calendar moves into the end of Argentina's spring season, Palmerino is not ready to say it's the end to the dry-weather issues there.

"You've got a real fight going on between the moisture flow from the north and a strong dry boundary from the south and west," he said. "The areas of greatest concern are most likely to be areas in the western part of the crop belt -- Cordoba, western Buenos Aires and La Pampa. They may be just enough in the dry air that tropical moisture from the equator stays north and east of those western areas."

Cordoba is Argentina's No. 1 soybean production state. La Pampa is a key sunflower producer.

From a market weather standpoint, this issue offers the potential for a neutral to bullish market weather factor through at least the first half of the Argentina growing season.

Argentina grain trade officials apparently share Palmerino's concern about the chance for lingering drought despite El Nino.

In a mid-November forecast reported by Dow Jones, the Rosario Grain Exchange predicted that ongoing drought will lead to a "significantly lower" 2009-10 harvest in Argentina than initial expectations. For soybeans, the Rosario Exchange forecasted a crop of 47 million metric tons, compared with USDA's projection of a 53-million ton Argentina soybean crop in '09-10.

"The drought affecting some provinces, such as Cordoba, Santiago del Estero, the west of Buenos Aires and the northern parts of the country, makes one think that its more likely that the estimates will fall rather than rise," the exchange said in the Dow Jones report.

Bryce Anderson can be reached at bryce.Anderson@dtn.com

(ES/AG)

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