Corn and soybean prices are climbing after a bouncy week linked to changing weather patterns.
Corn and soybeans each rose 2.2 percent to end Friday's session. Wheat also rose.
Weather forecasts are taking on more importance because corn and soybeans have been damaged by searing heat and a devastating drought that is dominating much of the country.
Rain predictions tend to drive down prices on expectations that crops will benefit and supplies will increase after harvest. Forecasts for smaller amounts of rain can push up prices on speculation that inventories will shrink.
Other commodities are climbing on hopes that European leaders will take definitive action to repair the region's fragile economy.
Prices are higher for gold, industrial metals and oil. Natural gas and coffee are lower.