Wheat prices are rallying as investors grow increasingly concerned about weather affecting production in Russia, Kazakhstan and Canada.

Analysts say wet weather in Canada and dry, hot weather in Russia and Kazakhstan could delay harvests or reduce the size of this year's crops. That means U.S. producers could see more demand for their wheat as buyers look for alternatives.

Farmers worldwide are in the midst of the peak harvesting season for wheat.

Wheat for September delivery is up 4.5 cents at $5.075 a bushel. Wheat prices have risen four straight days.