Corn futures rose on Monday, and hit a 1-month high as the US dollar fell against most currencies, and a large storm in some major US states, which lifted prices.
The Midwest states - known as the Corn Belt - were hit by a derecho storm, which damaged crops and will have an affect on the harvest season and supply.
Analysts said the storm damaged 14 million acres in Iowa, compared to estimates of 10 million acres.
The dollar index fell against a basket of currencies by 0.2% to 92.8 points at 20:19 GMT, with a high of 93.1 and a low of 92.7.
Corn September futures rose 2% to close at $3.31 per bushel, after hitting a day high of $3.31 and a low of $3.26.