homepage logo

Keeping an eye on El Nino

By Staff | Dec 4, 2009

As the U.S. harvest wraps up, many farmers, market analysts and meteorologists are closely watching the South American growing season for potential market indicators.

Weather watchers were taken by surprise, however, when weak El Nino conditions that existed earlier this fall suddenly surged in recent weeks.

“Where El Nino is heading will be a huge player in South America’s upcoming growing season,” said Mike Palmerino, a DTN senior ag meteorologist who spoke during a recent DTN weather outlook webinar. “In October, we started to see signs that the atmosphere was pushing into more of an El Nino pattern.”

An El Nino event is identified by warmer-than-normal sea surface temperatures. Rapid warming in the central Pacific Ocean, which developed quickly from late October to mid November, transformed a weak El Nino into a moderate event in just a few weeks. Unfortunately, it’s challenging to predict how an El Nino event will develop in the coming weeks, Palmerino said.

What El Nino does next will have huge implications, however, for weather in the months ahead, both in South America and in Iowa. In the southern hemisphere, a typical El Nino event increases the potential for higher rainfall, especially in southern Brazil and eastern Argentina. For the Midwest, the National Weather Service is projecting an El Nino winter with mild temperatures and moderate precipitation. “If this El Nino would crank up to the next level, however, all bets are off,” Palmerino said.

Argentina remains a swing area

In the soybean market, there’s an incredible amount of interest in Argentina’s rainfall prospects, said Palmerino, who noted that Argentina was locked in a drought pattern last year, especially in the western portions of its major grain-producing areas.

In fact, Argentina’s drought in 2008-2009 was the worst in 50 years. “Argentina appears to be the major swing area in terms of soybean production, depending on how the weather develops in the next few months,” Palmerino said. “They need moisture in February, because their February is like our August in the Midwest.

“Argentina’s dryness in the northwest, west and southwest bears watching, because if El Nino starts to weaken, things could deteriorate quickly.”

Unlike Argentina, Brazil hasn’t faced drought issues in its major soybean producing areas. In contrast, conditions have tended to be a bit too wet in the southern part of the country. Overall, conditions look nearly ideal in many areas, Palmerino said.

What about our winter?

Closer to home, weather patterns may be setting up for wet conditions in parts of the Corn Belt, Palmerino said. “The storm track looks like we could have wet conditions coming out of winter into spring for the third year in a row. While the northwest part of the Corn Belt and the northern plains look like they’ll catch a break, areas south and east of Des Moines could remain very wet with this pattern through the winter.”

The outcome, however, will depend on El Nino’s influence. While there’s no easy way to predict El Nino trends, Palmerino said the best bet is to track the Southern Oscillation Index, which indicates changes in sea-surface temperatures. A double-digit negative SOI value, which occurred in October, is indeed an El Nino trend, Palmerino said. While tracking the SOI can indicate where the weather might be headed, the ability to forecast SOI numbers is impossible, he added.

“The general view is a moderate El Nino through the first quarter of 2010,” Palmerino said. “There’s still a tremendous amount of uncertainty, however, and time will tell.”

Contact Darcy Dougherty Maulsby by e-mail at yettergirl@yahoo.com.

Please Enter Your Facebook App ID. Required for FB Comments. Click here for FB Comments Settings page