WHEAT - Down 2 to 5 cents per bushel

* Firm dollar pressures wheat futures as investors shed volatile assets from their portfolios. CBOT September soft red winter wheat hit resistance at 20-day moving average overnight.

* CBOT September soft red winter wheat last traded down 5-1/2 cents at $5.36-1/4 per bushel. K.C. September hard red winter wheat was 1-3/4 cents lower at $5.44 and MGEX September spring wheat was down 5-1/4 cents at $5.91 per bushel.

CORN - Down 2 to 3 cents per bushel

* Forecasts for rain and cool weather, beneficial for crop development, across the US Midwest weigh on corn market. CBOT September corn futures hit resistance at 20-day moving average during overnight trading session. Support noted near 40-day moving average.

* CBOT September corn last traded down 2-1/4 cents at $3.60 a bushel.

SOYBEANS - Down 6 to 7 cents per bushel

* Market setting back from two days of gains as weather forecasts strengthens expectations for bumper soybean harvest in US Midwest. Benchmark November soybean contract turned lower after hitting resistance near 20-day moving average overnight. Contract dropped below 30-day and 40-day moving average.

* Analysts expecting monthly National Oilseed Processors report to show that July crush totaled 161.745 million bushels, the highest ever for the month.

* Chicago Board of Trade reported 47 deliveries against August soybean contract. There were 50 soymeal deliveries and 95 soyoil deliveries.