Jan 06, 2023

Drought in Southern Brazil while Excess Wetness in Central Brazil

Author: Michael Cordonnier/Soybean & Corn Advisor, Inc.

La Nina is resulting in two weather extremes in Brazil; drought in the southernmost state of Rio Grande do Sul and excessive rainfall in central Brazil.

In the state of Rio Grande do Sul, Civil Defense authorities have declared a state of emergency in 45 municipalities due to drought and the number is increasing each day it does not rain. The near-term forecast from the Brazilian National Weather Service (Inmet) for Rio Grande do Sul is calling for very little chance of rain in the near term with the next chance of rain on January 12th. In the other southern states of Santa Catarina and Parana, the forecast is calling for light and scattered showers.

The long-range forecast for southern Brazil for the period January-February-March is calling for below normal rainfall especially for Rio Grande do Sul.

The corn crop in Rio Grande do Sul has already been negatively impacted by the dry weather for the third year in a row. Even farmers who have irrigation are reporting difficulties in supplying enough water to the crop. The soybeans in the state were planted late due to dry conditions and most of the crop is still in vegetative development, but some of the earlier planted soybeans are flowering and they need rain as soon as possible to avoid yield losses.

In contrast to southern Brazil, the weather models for central Brazil are calling for heavy rains in the states of Sao Paulo, Mato Grosso do Sul, Minas Gerais, Goias, Mato Grosso, and Matopiba (Maranhao, Tocantins, Piaui, and Bahia).

In the state of Minas Gerais, Civil Defense authorities are warning of very heavy rains that could be in excess of 8 inches over the next few days including areas of coffee and grain production. The states of Mao Grosso and Goias could receive upwards of 6 inches over the next seven days.

Excessive wetness in central Brazil could delay the soybean harvest that is already underway in parts of Mato Grosso and Goias. Farmers are concerned that the wet weather could result in lower soybean yields and poor quality seed. Each time a mature soybean plant undergoes a wet and dry cycle, the risk of fungal infections increase as well as the possibility of the soybeans sprouting in the pods.