Scattered showers in Parana and Sao Paulo states will give way to dry and warm weather with no risk of frost in coffee areas in the next 10 days, private forecaster Somar said on Monday.
Minimum temperatures on Friday ranged between 10 Celsius (50 Fahrenheit) in Pocos de Caldas in south Minas and 17 Celsius (68 Fahrenheit) in south-west Sao Paulo state.
Somar said in a daily report that, although a cold front was expected to bring showers to southern Brazil between July 4-6, it wouldn't touch coffee areas.
"Up to July 13 no cold fronts are expected to reach the coffee belt," Somar said.
Traders said that the harvest was gathering pace after a rain-delayed start and more coffee was coming onto the market.
Most coffee areas have had above-average rainfall in June. South Minas has had between 86 percent and 120 percent more than usual and Alegre in southern Espirito Santo 72 percent extra.
The weather is usually dry during the May to September harvest but south Minas had double the monthly average of rain in May and Varginha has already exceeded the June average.