The US polar vortex , which caused arctic weather and temperatures in some areas of the Midwest to drop to -40C , has forced grain traders and grain producers to close their facilities and adjust their transportation routes . Cargill temporarily closed all of its grain plants due to the deep cold front , while Tyson shut down six of its facilities on safety concerns . This has been one of the worst cold snaps to hit the US Midwest in decades. Archer - Daniels - Midland adjusted its transportation routes to avoid areas most severely affected by the severe weather . The overall harm to crops remains unclear , with farmers now beginning to assess damage .
The US polar vortex , which caused arctic weather and temperatures in some areas of the Midwest to drop to -40C , has forced grain traders and grain producers to close their facilities and adjust their transportation routes . Cargill temporarily closed all of its grain plants due to the deep cold front , while Tyson shut down six of its facilities on safety concerns . Archer - Daniels - Midland adjusted its transportation routes to avoid areas most severely affected by the severe weather . The overall harm to crops remains unclear , with farmers now beginning to assess damage .