Cool and rainy weather combined this week with a weak dollar to push the corn and soybean markets above recent highs. December corn climbed another 40 cents this week, a 37 percent gain since Labor Day, while November soybeans rose 50 cents.

The Department of Agriculture crop progress report, released weekly, has given credence to traders' bullishness. The report confirmed the drastic delays in the corn and bean harvest, both of which are weeks behind schedule. In addition to delaying the harvest, recent rains and cool weather have producers concerned about crop quality, which can be adversely affected as the corn and beans sit in the fields. On Friday morning, December corn was trading at $4.13 a bushel and November soybeans were at $10.28 a bushel.

This week, wheat futures broke upwards amid weather concerns and support from the grain and petroleum markets. Winter wheat, which is planted in the fall, has been suffering delays in recent weeks as well. Hampered by wet fields and the delayed bean and corn harvest, many producers have been unable to drill their wheat, contributing to wheat's upsurge this week. As of Friday morning, Chicago Board of Trade December wheat was trading at $5.74 a bushel, up 77 cents or 15.5 percent on the week.

Gasoline inventories nationwide dropped sharply last week, giving gasoline a boost. Unleaded gasoline for November delivery was up another five cents this week, reaching a peak of $2.07 per gallon, a 29 percent increase since its recent low one month ago at $1.61. In recent weeks, refiners have cut back on gasoline production, lending support to the market, which had been anemic for most of the summer.

Cocoa: December Cocoa futures hit a contract high at $3,412 per metric ton on Friday morning. This renewed strength came as poor weather and a labor strike in the Ivory Coast helped guide cocoa upwards. The Ivory Coast is the world's largest cocoa producer and currently produces 37.4 percent of the global harvest, and the problems there have combined with strong earnings from chocolate companies to push prices higher. In the past two weeks, cocoa futures have risen $362 per metric ton, or 11.9 percent.

Opinions are solely the writer's. Walt Breitinger is vice president of commodities at Wells Fargo Advisors LLC. He can be reached at (219) 738-6460.