CHICAGO, June 22 (Reuters) - U.S. corn futures were mostly lower on Tuesday as the latest weather forecasts called for much-needed rain to soak the U.S. Midwest just as crops enter key development stages, traders said.

"It has been very dry but dryness in the early stages that we have been in is much less meaningful than dryness in pollination that is coming up here in the next couple of weeks," said Ben Buie, grain team leader at MaxYield Cooperative. "We are really hitting the crucial time."

Soybean futures were firm, supported by a bounce in the soyoil market as well as signs that the recent price declines have renewed interest in U.S. supplies from overseas buyers.

Spring wheat futures surged to their highest level in nearly two weeks after a U.S. Department of Agriculture (USDA) report that pegged the condition of crops below market forecasts stoked concerns about global supplies. Winter wheat contracts were steady to weaker, pressured by the advancing U.S. harvest.

At 10:46 a.m. CDT (1546 GMT), MGEX spring wheat for September delivery was up 21-1/2 cents at $7.89 a bushel, peaking at its highest price since June 8.

CBOT September soft red winter wheat was down 2-1/2 cents at $6.62-1/2 a bushel after hitting its highest level since June 14 overnight. The USDA said just 27% of the spring wheat crop was in good-to-excellent shape, a 10-point drop that was well below expectations.

"The production outlook for high-protein wheat continues to dim," said Tobin Gorey, director of agricultural strategy at Commonwealth Bank of Australia.

CBOT December corn futures were down 10 cents at $5.47 a bushel.

Although most corn contracts were trading in negative territory, the front-month July contract firmed 4 cents to $6.63-3/4, with tight supplies in the country underpinning prices.

CBOT November soybeans were up 1/4 cent at $13.19-1/2 a bushel. (Reporting by Mark Weinraub in Chicago Additional reporting by Colin Packham in Canberra Editing by Edmund Blair and Matthew Lewis)