South America Calling

Scattered showers have been very frequent across most of South America over the last several weeks. However, they have been scattered for most of Argentina and southern Brazil during this time. While the rainfall has been enough to maintain soil moisture, it has not been sufficient to improve it. Dry areas have developed, but then eventually rained on.

This week, some spots in the state of Cordoba and northern La Pampa in Argentina had been drying out. But a front came through on Wednesday, Dec. 18, and produced scattered showers right in that area, with amounts of 15-40 millimeters (0.6-1.6 inches) recorded. Other areas in Argentina stayed dry from the front, and those with fair soil moisture will now fall back a bit, waiting for their chance for rain.

Conditions have been similar, though not as severe in southern Brazil. While drier periods have developed in recent weeks, the fronts coming up from Argentina have produced more widespread and heavier rainfall, more on the border of widespread 25-50 millimeters (1-2 inches) at a time, with patches of lower amounts.

Rain has been coming in a timely fashion, which has been favorable for crop development in these areas. The active pattern of these fronts has also kept temperatures at a more seasonable range, and many times further below normal than above normal. That has kept water demand lower than normal as well.

The pattern will continue for the next couple of weeks, though at a more isolated pace than what we have seen over the last couple of weeks. Both the European and American models seem to agree that below-normal rainfall will continue across both Argentina and southern Brazil, although they also agree that fronts will continue to move through at a somewhat regular pace. They just aren't strong enough to produce a lot of precipitation. The cooler temperatures have something to do with that, with lower energy for these fronts to tap into to produce storms. The pattern continues into early 2025. The issue whether or not this matters in terms of corn and soybean production for both countries.

A case can be made either way. It is my general opinion that it will not matter as much. For one, it is still early in the season. Argentina has an extremely long growing season, essentially in two parts. While there is still about a quarter of the crop yet to be planted, some of it was planted three months ago and is pollinating. The drier stretch is damaging for that early planted variety. But that is a rather small portion of the crop, and mostly in the north, where soil moisture is better, and showers have been more frequent. Soybean planting didn't start until November, and the pod-filling stage is still well into the future when rainfall will be most important.

In southern Brazil, it's a little more concerning. Full-season corn in the state of Rio Grande do Sul is pollinating and filling grain, and the lower rainfall amounts will be somewhat discouraging for producers there, especially since soils have more of a sandy texture there. However, the safrinha corn crop that comes after soybeans, is the big crop for Brazil, accounting for roughly 75% of their overall production. While some issues to the early crop might bring overall production a tick, there does not seem to be a lot of it.

Some early-planted soybeans in the state of Parana need the rain as well. However, less than half of the crop has reached the filling stage, and 20% has yet to reach flowering, according to the government in the state. Drier conditions are not great for this crop, but it should also not be alarming. As long as some precipitation occurs, it will be better than nothing, and that seems to be the case moving forward. With central Brazil's weather still looking good during their fill period, small adjustments downward should not reduce the impact on what looks to be a near-record soybean crop for the country.

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John Baranick can be reached at john.baranick@dtn.com

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