The most-active wheat contract on the Chicago Board Of Trade was up 0.1 percent at $5.14-1/4 a bushel by 0338 GMT, adding to Thursday's gain of 1.4 percent. Wheat has gained about 0.6 percent so far this week after three straight weekly falls.
Soybeans were up 0.1 percent at $9.13-1/2 a bushel, rising for a third session in a row on concerns over adverse weather in Brazil and Argentina.
Soy has added nearly 2 percent so far this week, in what could be its strongest weekly gain in a month.
Rain and hail storms have slowed soybean planting in Argentina over the last week, washing out some fields and raising concerns that continued wet weather could put the 2018/19 crop at risk, the Buenos Aires Grains Exchange said in a report on Thursday.
Erratic rains in Brazil, which have already been hurting the soybean crop, are also beginning to stress sugarcane fields, which this season are more susceptible due to plant aging, experts told Reuters.
Meanwhile, corn was also up for a third consecutive session, trading 0.1 percent higher at $3.80-1/4 a bushel after gaining over 1 percent in the previous session. It was set for a weekly rise of about 1.3 percent.
U.S. farmers, already battered by the trade war with China, are facing increasing anxiety as the partial government shutdown nears the two-week mark, leaving crucial aid and loan payments in limbo. The shutdown has blocked assistance for many farmers, who at this time of year begin budgeting for next season's planting.