Climate is expected to impact wheat and coffee production in southeastern Brazil.

The passage of a cold front over the Southeast Region is expected to bring rain to areas of São Paulo, Minas Gerais, Rio de Janeiro, and Espírito Santo throughout this week. The rainfall predicted by the National Institute of Meteorology (Inmet) tends to favor wheat, contributing to maintaining soil moisture and promoting crop development. 

On the other hand, the occurrence of rain during the coffee harvest and the possibility of inducing early flowering require attention from producers, especially in the main coffee-growing regions of São Paulo and Minas Gerais.

Impacts on coffee farming

In the case of coffee farming, the forecast coincides with a sensitive period in the crop cycle. A large portion of the Arabica coffee plantations are currently being harvested in the main producing regions of the Southeast, such as Southern Minas Gerais, Cerrado Mineiro, Zona da Mata Mineira, Mogiana Paulista, and Alta Paulista. 

In this context, the predicted rains may hinder harvesting and drying operations, increase the moisture content of the fruit, and raise the risk of unwanted fermentation, negatively impacting the final quality of the beverage.

In addition to operational impacts, rainfall also requires attention due to the physiological stage of the crop. After harvest, the flower buds typically remain dormant during the dry winter period, an important condition to ensure a uniform main flowering in early spring. 

However, there are already reports of early flowering in some producing regions of São Paulo and southern Minas Gerais. In this scenario, rainfall can favor the premature breaking of dormancy in flower buds and stimulate out-of-season flowering, which tends to cause uneven development and ripening of the fruit, increasing the proportion of green beans and reducing the potential quality of the beverage. After the passage of the cold front, the entry of colder air tends to temporarily slow down the physiological activity of the plants, with a greater reduction in temperatures in higher altitude areas of the Serra da Mantiqueira and southern Minas Gerais.

In Varginha (MG), the rainfall observed throughout April, May, and June was irregular, but occurred within a context of mild temperatures and low evaporative demand, conditions compatible with the coffee harvest period. For the coming days, the forecast of rain associated with the cold front reinforces the need for attention to harvesting and drying operations, as well as monitoring for possible effects on the dormancy of flower buds.

A more favorable scenario for wheat.

For wheat, the outlook tends to be favorable in the cultivated areas of São Paulo and Minas Gerais, since the predicted rains should contribute to maintaining soil moisture and the vegetative development of the crops. In Itapeva (SP), an important wheat-producing center, the rainfall volumes observed throughout April, May, and June contributed to maintaining adequate water availability, with no indication of significant restrictions for the crop. The forecast of persistent rainfall reinforces this scenario, favoring plant development.

The lower temperatures forecast for the coming days also tend to benefit wheat, as the crop performs better under mild weather conditions. In early-stage crops, moderate cold tends to be well tolerated and may even favor tillering. On the other hand, areas in more advanced stages, especially during stem elongation, flowering, and grain filling, are more sensitive to sharp temperature drops, which requires monitoring of weather conditions.

The rainfall that occurred throughout April, May, and June contributed to maintaining adequate water availability for wheat cultivation in Itapeva (SP). It is also observed that minimum temperatures remained predominantly at levels favorable to crop development. For the coming days, the forecast indicates continued mild temperatures and rainfall, a scenario that tends to favor the continued development of the crops.

Weather forecast

In the coming days, the passage of a cold front over the Southeast Region will favor rainfall in areas of São Paulo, Minas Gerais, Rio de Janeiro, and Espírito Santo, with the highest accumulations concentrated between southern Minas Gerais, northern and northeastern São Paulo, and southern Rio de Janeiro, where volumes could exceed 40 mm.

After the system passes, a mass of colder air will move over the region, causing temperatures to drop, especially in eastern São Paulo and southern Minas Gerais, with values ​​below 16ºC. This scenario should maintain milder weather conditions throughout the week, with lower evaporative demand and greater soil moisture retention.

Given this scenario, weather conditions tend to favor the development of winter crops, especially wheat. For coffee cultivation, however, the period requires attention regarding the management of harvesting activities and crop monitoring, since the combination of humidity and lower temperatures can influence both field operations and the physiological dynamics of the plants. In this context, continuous monitoring of weather updates is essential to guide crop management and the planning of field operations.