SAO PAULO—Brazilian agricultural areas were hit by frosts for a third day on Thursday, affecting corn, coffee, and sugarcane as well as produce for local markets such as beans, potatoes and tomatoes, according to consultancy Rural Clima. In a note to clients, Rural Clima said frosts hit the west and north of Sao Paulo state, the Minas Gerais triangle, the southwest of Goias, and some areas of southern Minas Gerais state. “It has affected coffee, sugarcane, pasture, potatoes, corn, beans, and tomatoes,” Rural Clima meteorologist Marco Antonio dos Santos said. The corn crop, possibly the most affected by this week’s frosts, may be reduced by 6 million tonnes, he added. “We were expecting a second corn crop of around 62 to 65 million tonnes. Now we can surely say it will be below 60 million tonnes,” he said. Parana, the second-largest corn-producing state in Brazil, was strongly hit by frost …