Heavy snow in parts of the northern U.S. could prevent some farmers from harvesting the rest of their corn and soybeans until 2020 in the latest weather-related blow to growers.

Flooding from torrential rains delayed spring seeding and prompted record amounts of acres to go unplanted. As of Sunday, the U.S. corn harvest was just 84% completed, the slowest rate in a decade. If crops are abandoned in fields until the spring, that's likely to further tighten supplies at a time when cash prices are already on the rise.

"Very few have started harvesting corn and many, including myself, will not harvest corn until next spring," said Monte Peterson, who grows corn and soy in Valley City, North Dakota, and is also a director on the American Soybean Association.

North Dakota was the furthest behind on gathering among major producers, with just 30% corn harvested, according to the U.S. Department of Agriculture.

Chicago-based consultant AgResource Co. estimated that as many as 2.4 billion of bushels of U.S. corn will still be in the fields as of Thursday's Thanksgiving Day holiday. Fields that go unharvested until spring could see yield losses of 20%-40%, according to the firm. The USDA estimates this year's crop will total 13.7 billion bushels.

The wet weather that's plaguing farmers is also having a knock-off effect on other markets. For example, high-moisture content in grain contributed to shortages of propane, which is used to dry corn and heat homes.

Enterprise Products Partners indefinitely extended a shipping rate for Texas-to-Illinois propane, the company said in a letter. The tariff rate had been set to expire Dec. 13, but propane supplies remain tight.

And it's not just corn and soybean seeing woes. There will be fewer harvested acres of crops including spring wheat, sugar beets and potatoes amid the wet weather.

The USDA's weekly crop progress and conditions report had been scheduled to conclude for the 2019 season this week. But due to delays in harvest progress, the government is evaluating how long it needs to continue.

This is article was written by Isis Almeida, Michael Hirtzer and Dominic Carey, reporters for Bloomberg.