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August 26, 2015

How Might El Nino Impact South American Weather?

Meteorologists generally agree that El Nino should remain strong at least through the end of the year and it is possible that it might end up being one of the strongest on record. There is no guarantee how it might impact the crops in South America, but below is a general idea about the potential impacts.

Southern Brazil - Generally El Nino correlates with above normal rainfall in southern Brazil (the states of Parana, Santa Catarina, and Rio Grande do Sul) during the spring planting months of September, October, and November. It could result in planting delays for soybeans, but unless the delays are extreme, it would probably not result in any yield reductions. In fact, ample rainfall during the growing season could result in above average soybean yields in southern Brazil which is the second largest soybean producing region of Brazil.

Full-season corn is the first crop planted in southern Brazil starting in mid-to-late August as the weather permits. Soybean planting generally starts in late September and ends with the planting of the double crop soybeans in November or early December. If the predictions for heavier than normal rainfall verifies, the one crop that could be negatively impacted would be wheat which is harvested during October and November.

Center-west Brazil - There doesn't appear to be a high correlation between El Nino and rainfall in the center-west region of Brazil, but the temperatures may end up being hotter than normal. This is the main soybean, corn, and cotton producing region of Brazil. Soybeans are generally planted in September and October and the corn is planted in January and February after the soybeans are harvested. Most of the cotton is planted in January after the soybeans are harvested.

Northeastern Brazil - In this region of Brazil, El Nino is generally correlated with below normal rainfall and higher than normal temperatures. The main crop in this region is soybeans followed by cotton and corn. Approximately 10% of the soybeans in Brazil is produced in northeastern Brazil. Planting starts later in northeastern Brazil than in the other regions of the country due to a later start of the summer rains. Planting generally starts in November and extends into January. Corn is planted first followed by soybeans and then cotton.

Agricultural production is expanding in this region and if this correlation verifies, it could be problematic for the crops in the region. Northeastern Brazil is already the driest part of Brazil and a reduction in rainfall could push the region into drought. It is too early to say that will happen, but it needs to be watched.

Southeastern Brazil - There doesn't appear to be much of a correlation between El Nino and rainfall in southeastern Brazil, but temperatures may be above normal. The two main crops in this region are sugarcane and coffee in the states of Sao Paulo and Minas Gerais.

Argentina - El Nino is generally associated with above normal rainfall across Argentina in the spring and summer months. There have already been very heavy rains in central Argentina in recent weeks resulting in some of the worst flooding in 30 years. It remains to be seen if this pattern carries through until planting begins. Corn planting generally starts in September and extends until late January. Soybean planting starts in October and extends until December.

The topography of central Argentina is very flat and the soils have a high water holding capacity. Therefore, if the area becomes saturated with heavy rainfall, it can take a relatively long period of time for the water to drain. Conversely, the area can withstand relatively long periods of dry weather without the crops suffering significant moisture stress.

Paraguay - I have not seen any direct comments about how El Nino might impact Paraguay, but since the country borders on southern Brazil and northern Argentina, I would expect that it would have the same correlation as southern Brazil and northern Argentina - above normal precipitation.

Soybeans are by far the main crop in Paraguay and they will start planting soybeans in late August or early September, if the weather permits. There is not a soybean-free period in Paraguay like there is in Brazil, so farmers can start planting whenever they feel the weather permits. Farmers in Paraguay also plant a lot of safrinha soybeans as well and the second crop of soybeans will be planted in January and February.