AccuWeather 2019 South America autumn forecast
El Niño is officially underway and will continue to influence the weather patterns across South America into the autumn, including rainy spells from Peru though Brazil.
Severe drought will grow worse from Colombia through Venezuela and French Guiana as the El Niño-fueled rain stays to the south.
Rain to frequent Peru to Brazil, northern Argentina
Wet weather will be common for many areas of South America located south of the equator this autumn with heavier downpours bringing the risk of flash floods.
“Weak El Niño conditions should result in several opportunities for rainfall across Ecuador and Peru into the Amazon Basin of Brazil with rainfall expected to average near to above normal,” AccuWeather International Forecasting Manager Jason Nicholls said.
El Niño is a part of a routine climate pattern that occurs when sea surface temperatures in the tropical Pacific Ocean rise to above-normal levels for an extended period of time. This can influence weather patterns across the globe.
Sea surface temperature departures in the Pacific during a past El Niño. (Image/NASA)
Flooding downpours have been an issue during the summer, particularly in Peru. Over 1 million people in Peru were affected by deadly floods during the season, according to UNFPA.org.
The anticipated wet weather could cause more incidents of flooding throughout the autumn.
Residents cross a flooded street in Lima, Peru, Tuesday, March 21, 2017. (AP Photo/Martin Mejia)
Rain is also in the offing for many areas from the north coast of Brazil through northern Argentina.
“Much of southeast Brazil into Paraguay, Uruguay and northern Argentina will have frequent rounds of rain which should maintain overall favorable conditions for crops across these areas,“ Nicholls said.
However, the ample rainfall early in the season will fade across central and northeastern Brazil by April and March.
“Despite the wet start to the season, there will be dryness problems in eastern Bahia and northern Minas Gerais as well as parts of Espirito Santo,” Nichols said.
The earlier in the autumn that the rain retreats, the higher the chance for drought conditions to develop.
Severe drought to worsen in Colombia, Venezuela
While El Niño helps to fuel flooding downpours across Ecuador and Peru, it will leave areas farther north deprived of rain.
“Conversely, drought conditions will persist across portions of Colombia and Venezuela to French Guiana,” Nicholls said.
“Scattered rains may reach these areas late in the season as waters off the west coast of Colombia are expected to warm during the season,” he added.
Despite the chance for late-season rain, it would likely be insufficient to ease drought concerns.
Drought conditions have been gradually growing worse across this part of South America, affecting millions of people across the region.
One in 10 municipalities in Colombia are without water due to extreme drought conditions, according to Colombia Reports. Even more municipalities may run out of water this autumn due to the anticipated weather pattern over the coming months.
Water levels in hydroelectric dams are also running well below normal following unusually low rainfall.
Drought conditions are expected to grow worse before rain returns and brings some relief to the drought-stricken regions of South America.
Summer heat to persist into autumn across Chile, Argentina
Sizzling summer heat may carry over into the start of autumn for parts of Chile and Argentina before temperatures drop later in the season.
Nicholls anticipates warm and dry conditions to dominate northern Chile into Argentina during March and April with the risk of heatwaves.
“There can be improved rainfall chances across central Chile, including Santiago, later in April and May,” Nicholls said.
However, the season as a whole is likely to end drier than normal for this region.
Meanwhile, areas to the south can expect wetter weather as storms begin to track in from the Pacific Ocean.
“It will be dry and warm across southern Chile and southern Argentina for the first half of the season, but southern Chile will likely turn wetter late in the season,“ Nicholls said.
These storms may deliver some snow to the southern Andes ahead of winter.
Report a Typo
