Warmth will be the trend across much of Argentina and the Pacific Coast this autumn, with dryness leading to drought concerns in some areas.
Meanwhile, rounds of rain will limit temperatures and dryness across much of northern and eastern South America.
Rain to frequent northern, central South America Rounds of rain will soak much of the northern tier of South America this autumn, limiting drought concerns.
While rain frequents northern and eastern Brazil, drier conditions are in the forecast for southern regions of the country.
“Southern Brazil, namely Rio Grande Do Sul to Parana, will start the season drier than normal before trending toward a more active and wetter pattern later in the season,” Nicholls said.
“The wet pattern can lead to harvesting delays, but far southern Rio Grande So Sul can average drier than normal for the season,“ Nicholls added.
Drought concerns to build in Argentina, Uruguay The dry conditions persisting across Argentina this summer will continue into the autumn, putting the country at risk for drought.
These areas will continue to average drier than normal through the autumn,” Nicholls said.
“The drier- and warmer-than-normal pattern will likely further stress corn and soybeans [grown across the region] as they push into maturing,” Nicholls said.
Similar conditions are expected for northern and central Chile with waves of heat in March and April, including in the capital of Santiago.

This drier weather pattern across the South is consistent with what is expected during a La Niña winter.
(MORE: What La Niña Conditions Mean for Winter in the U.S.) The latest update from NOAA indicates that La Niña conditions are expected to persist through winter.
According to the U.S. Drought Monitor, "over the last 60 days, extensive areas of the country have recorded below 25 percent of normal precipitation, from the Southwest into the central Plains and Midwest as well as in the Southeast and into the Mid-Atlantic."
In addition, as of Jan. 9, "some areas of the Oklahoma and Texas panhandles and southern Kansas have gone 95-100 straight days with less than 0.10 inches of precipitation, with several locations reporting no precipitation at all during that time."
In addition, almost 77 percent of the region is currently abnormally dry compared to just over 8 percent in early September.
In the South, which includes Tennessee and Mississippi westward into Texas, only 0.45 percent of the region was seeing drought conditions on Sept. 5, and that percentage has jumped to 45 percent as of Jan. 9.
The percentage of the area that is at least abnormally dry has also dramatically increased from just under 3 percent in early September to almost 74 percent in early January.
However, the weather pattern that has been in place has brought colder-than-average temperatures so far this winter to much of the southern and eastern U.S., with temperature the greatest above average in the Southwest.
(MAPS: Weekly Planner) Given the expectation that La Niña conditions will last through the winter and will then transition to neutral conditions, neither La Niña or El Niño, this spring, there are concerns that drought conditions will worsen.
The precipitation outlook from NOAA indicates that generally drier-than-average conditions are expected through March from the Southwest into the southern Plains and much of the South.

The arrival of autumn will bring significant changes to the weather across much of Europe.
Following a hot and dry summer, beneficial rain will fall across parts of Italy and the Balkans, bringing relief from drought and wildfires.
“The change to drier weather will not last throughout the season, as a several week stretch of wet weather returns to eastern France, Germany and western Poland in October,” AccuWeather Meteorologist Tyler Roys said.
“There will be a significant increase in the risk of windstorms across the British Isles from late October into November,” Roys said.
“Northern Ireland and Scotland will face the greatest risk for significant impacts.” At least one post-tropical system is predicted to impact the Isles during this time, presenting a high risk for flooding and damaging winds.
Beneficial rain to arrive across Italy and Balkan Peninsula The Iberian Peninsula will continue to endure drought conditions; however, relief will arrive for Italy and the Balkans following a hot and dry September.
The drought conditions currently plaguing parts of Italy and the Balkans will continue into early autumn as above-normal temperatures and minimal rainfall are expected.
“Drought relief will come in October and November as rainfall increases across both Italy and the Balkans,” Roys said.
Warmth to prevail across eastern Europe into October before biting cold shots invade late A warm start to autumn is expected from the Baltic states into Ukraine.
This cold air will also bring the risk for a late-season snowstorm in Ukraine and Belarus.

Lack of rain over the autumn, winter and early spring has left some rivers and reservoirs,particularly in the south and west, with dwindling levels.
Until now water companies have played down talk of hosepipe bans, but as the dry weather continues the public has now been warned that restrictions could be on the way in some areas unless reservoir levels are replenished by prolonged rainfall.
Water supplier Affinity, which covers large areas of the south-east of England, says it is "monitoring the situation closely with clear plans in place".
"January to March saw rainfall 50 to 70 per cent below average in our region" the company said.
"We have not seen the rise in groundwater levels we expected, and some rivers have seen flows decrease."
A spokesman for Southern Water said: "The winter of 2016-2017 was drier than average, particularly in the months leading up to Christmas.
Water companies say work has started with farmers to reduce the impact of the continuing dry weather as summer approaches.
Environment Agency spokesman George Leigh said some rivers, ground waters and reservoirs are lower than normal for the time of year.
But South East Water’s head of water resources Lee Dance said that while the winter has been drier than usual, the company does not envisage water shortages this summer.
"A continued lack of rainfall could lead to water restrictions."

Rain and thunderstorms will frequent much of South America this autumn as wet weather occurs from Argentina to parts of Colombia and Venezuela.
Drought to improve in Colombia, Venezuela but worsen in northeastern Brazil The drought gripping Colombia and Venezuela will improve with a wet pattern continuing into autumn.
This includes helping to raise the water level at the Guri Dam, one of the largest water reservoirs on Earth.
While rain helps to improve the drought in Colombia and Venezuela, dry weather will cause drought conditions to worsen in Brazil.
Some rain is expected to move over these areas throughout the season; however, below-normal rainfall will cause the drought to persist and possibly worsen.
Rounds of rain, thunderstorms to slam Argentina to southern Brazil An active weather pattern is on tap for much of Argentina, Paraguay, Uruguay, Bolivia and southern Brazil this season as waves of rain and thunderstorms move across the region.
“It seems like there will be an active weather pattern with no prolonged dry periods and near- to above-normal rainfall,” Miller said.
The threat for thunderstorms will be mainly early in the season before gradually tapering off as the fronts deliver steadier rain instead, AccuWeather Lead International Meteorologist Jason Nicholls said.
Most of Chile should see near-normal rainfall, but a few pockets could receive above-normal rainfall, Miller added.
Warm, dry weather is also on tap for southern Argentina and southern Peru.