Heavy rain is expected to spread south from coffee farms in Minas Gerais into Sao Paulo state and northern Parana over the next five days, independent forecaster Somar said on Friday.
Around 80 millimeters (3.1 inches) of rain is forecast in southern Minas and 100 mm (3.9 inches) in southwest Sao Paulo state.
In a daily report, Somar noted that beneficial rain returned this week to the forested coffee zones of eastern Minas Gerais and Espirito Santo.
"During the weekend, rains will move south and cover the main coffee belt," Somar said.
In an extended 10-day forecast, Somar said rain would remain concentrated in the main arabica belt of Parana and southern part of Sao Paulo.
But only isolated showers are forecast in the northern part of Sao Paulo state and the Cerrado region of Minas Gerais.
The forested coffee zones of Minas Gerais and Espirito Santo, as well as coffee farms in southern Espirito Santo and Bahia have had much more rain than usual in January.
In December, Alegre in the south of Espirito Santo was wettest with 294 millimeters (11.6 inches) of rain, 43 percent above the 5-year average. But the key coffee area of Varginha in south Minas had only 192 mm (7.6 inches), or 33 percent below average.