USDA's first corn and soybean harvest estimates are due out tomorrow — Aug. 12 —  and at least two private agricultural research firms are pegging the crop as the second largest ever. That's despite this spring's flooding and fewer acres planted.

Informa Economics, a private agricultural research consulting firm, is forecasting the total U.S. corn crop at 12.33 billion bushels. That's based on a 155.4-bushel-per-acre average yield, which would put the below last year's record 13.1 billion bushels, but higher than 2004's crop of 11.8 billion bushels.

Analysts at FC Stone, a brokerage firm, also projects a large 2008 corn crop at 12.197 billion bushels, averaging 154.5 bushels per acre.

As for soybeans, Informa analysts look for a 3.054-billion-bushel crop, based on an average yield of 42 bushels per acre. FC Stone estimates it at 2.993 billion bushels with a 40.5-bushel-per-acre average yield.

In 2007 the U.S. soybean crop fell to 2.6 billion bushels from a record 3.2 billion bushels in 2006, as acres shifted from soybeans to corn to meet ethanol demand. This year, some of those acres shifted back to soybeans.

Darrel Good, University of Illinois agricultural economist, believes USDA's corn and soybean crop report will be lower than Informa's estimates. Although he does admit that Informa's yield estimates are consistent with USDA's seasonal crop ratings. Summer weather has been good for crop growing conditions. Corn and soybean prices have trended lower in recent weeks from record-setting highs.

Still in question is how well the crops can continue to make up lost time from a late start, and how long  the season will actually be-- early frost or a wet fall would have negative impacts.

"Crop size will be influenced by remaining growing season weather and soybeans are vulnerable to an early freeze," notes Good. "A lot of yield uncertainty will still persist after the August report."