By Karl Plume
CHICAGO, Aug 15 (Reuters) - U.S. corn and soybean futures rose on Friday on short-covering ahead of the weekend and a closely-followed crop tour set to begin surveying fields across the Midwest next week.
Chicago Board of Trade wheat also edged higher after concerns about big global supplies dragged the market to contract lows earlier this week.
Corn and wheat futures were on pace for weekly declines for a fourth straight week as abundant supplies weighed on both markets, while soybeans were set to post a weekly gain for the first time in four weeks after a smaller-than-expected U.S. crop forecast from the U.S. Department of Agriculture this week.
"The risk is, at the moment, to the upside. The funds are short grains and oilseeds, and we've got that crop tour that starts on Monday," said Craig Turner, a commodity broker at StoneX.
"If you're short and you're up and you've got a winning position, I don't know why you wouldn't take a little profit here heading into the weekend with the crop tour coming up."
CBOT December corn CZ25 was up 6-3/4 cents at $4.04 a bushel by 12:20 p.m. CDT (1720 GMT), while November soybeans SX25 added 14-1/2 cents to $10.43 a bushel. CBOT September wheat WU25 was 1-1/2 cents higher at $5.05 a bushel.
The Pro Farmer Midwest crop tour will estimate corn yields and gauge soybean production potential across seven states next week before issuing its crop outlook next Friday.
Grain traders will be monitoring findings after the USDA earlier this week projected a record-smashing U.S. corn harvest and smaller soybean crop.
A recent uptick in corn export demand, sparked by low prices, has limited further pressure in corn futures.
A stronger-than-expected July U.S. soybean crush , released at mid-session by the National Oilseed Processors Association, offered soybean futures an additional lift.