South America Calling         12/19 09:12

   South American Weather in Good Position Heading Into Important Part of 
Growing Season

   Though it hasn't been perfect by any means, the weather situation in South 
America generally remains favorable for crops.

John Baranick
Staff Meteorologist

   Complicated weather patterns and underwhelming wet season rainfall in 
central Brazil led to mixed conditions for much of South America through the 
end of November. But the weather in December has been much more favorable so 
far. That is setting up corn and soybeans with a rosy outlook for the continent 
as we head into the most important stretch for weather.

   Fronts have been frequent across Argentina and southern Brazil for several 
months, but the frequency has slowed down in December. That has meant a slow 
decline in soil moisture -- but not in all areas. Northern Argentina, Paraguay 
and the state of Parana in southern Brazil have had frequent and heavier 
showers this month despite those showers coming at a slower clip.

   Not all areas have benefited though, and southern Argentina, Uruguay and the 
state of Rio Grande do Sul in southern Brazil have not had nearly as much 
rainfall. It has been more patchy and some areas have seen amounts well below 
normal during the last three weeks.

   But earlier precipitation in the spring has meant soil moisture here is 
still overall favorable despite the lower rainfall frequency. Considering the 
frequent fronts have meant variable temperatures and limited periods of heat, 
it's an overall favorable weather situation for this portion of the continent. 
The Buenos Aires Grain Exchange agrees with good-to-excellent ratings on corn 
at 88% and soybeans at 65%. That is a significant improvement from last year in 
corn, but similar in soybeans. The favorable weather has meant planting for 
corn is well ahead of the average pace, with second-season planting in 
Argentina at the fastest pace in the last 10 years, just slightly ahead of last 
year's rapid pace.

   Producers are more interested in planting their corn at the expense of 
soybeans, which is slightly slower than the normal pace, but still overall 
occurring at a good clip.

   Farther north, central and northern Brazil had a rough two months to start 
the wet season. The daily showers and thunderstorms that characterize the 
season had been nearly nonexistent. Instead, rainfall was coming from fronts 
sweeping northward from Argentina. While the pace of those fronts was more 
frequent than normal, the dry days between the fronts meant moisture was rather 
limited and there were some concerns about the need to replant soybeans.

   Mato Grosso, Brazil's largest state for soybean production, started at a 
rapid planting pace because of one of these fronts, but ended up slower than 
usual because of the infrequent rainfall and limited soil moisture. Some 
replanting and withering early planted soybeans was reported, and soil moisture 
was near record low for the end of November. That is a time when early planted 
soybeans are blooming, a grave concern for pod-fill.

   But showers quickly increased in both coverage and intensity in the first 
week of December. And while soil moisture is still below normal in a lot of 
areas, the frequent rains during the last three weeks have quickly increased 
the available amounts for developing soybeans and is much improved to where 
soil moisture is currently not a concern as those early planted soybeans start 
to fill pods.

   The main fill period for soybeans is in January. The forecast is favorable 
for most areas here, leading to further improvements and alleviating concerns 
for most of this crop. The concern, though, could come with the second-season 
(safrinha) crop. The lack of moisture at this stage will limit the available 
moisture for the safrinha crop unless forecasts improve. DTN's forecast for the 
December-through-February period calls for below-normal precipitation during 
the season, and lower amounts in the March-through-May period as well, leading 
to some concerns later. But for now, the weather situation is overall a good 
one, and better than expected for the 2025-26 season.

   To find more international weather conditions and your local forecast from 
DTN, visit https://www.dtnpf.com/agriculture/web/ag/weather/interactive-map.

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




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