* Corn, soybeans steady after 2-day drop as U.S., Brazil crops watched

* Rainfall caps gains

* Wheat underpinned by northern hemisphere harvest concerns

* Delta coronavirus strain tempers demand sentiment (New throughout; updates prices, market activity and comments; new byline, changes dateline previously PARIS/SINGAPORE)

CHICAGO, Aug 5 (Reuters) - Chicago corn and soybeans climbed on Thursday on stronger export sales, though gains were capped by rainfall across parts of the U.S. Midwest.

Wheat traded near even, supported by firmer grains complex and distressed crops across North America.

The market also awaits the U.S. Department of Agriculture monthly supply and demand report on Aug. 12 for an update on U.S. harvest prospects.

The most-active corn contract on the Chicago Board of Trade (CBOT) was up 7-1/2 cents at $5.54-1/4 per bushel by 12:17 p.m. (1717 GMT).

CBOT soybeans added 8-3/4 cents to $13.34-1/2 per bushel, while CBOT wheat eased 3-1/2 cents to $7.25-1/4 per bushel.

"Demand is showing up. That’s what the concern in the market was," said Chuck Shelby, president at Risk Management Commodities.

U.S. exporters sold 898,400 tonnes of corn during the week ended July 29, topping market expectations. Exporters also sold 436,200 tonnes of soybeans.

Soybeans were also supported by a daily sales notification of 300,000 tonnes of soybeans for delivery to unknown destinations during the 2021/2022 marketing year.

Demand optimism was capped by the spread of the Delta coronavirus variant in some of the world's largest economies.

Spotty rainfall across the U.S. Midwest limited gains, though dryness persists in western growing regions.

"There’s good crop out there, but there’s also people really struggling because of a lack of moisture," said Jeff French, owner of Ag Hedgers. "the market is going to be in a tug of war over final yields. We’ll get a good sense of that once the combines run."

Corn also found support from private firms assessing Brazil's battered corn crop, as consulting firm Agroconsult pegged the South American producer's second-crop at 60.9 million tonnes, down 4.4 million tonnes from its previous estimate. (Reporting by Christopher Walljasper; additional reporting by Gus Trompiz in Paris and Naveen Thukral in Singapore; Editing by David Gregorio)