Ontario Weather Patterns Impact Corn Prices and Crop Development

The past two weeks have seen significant weather patterns in Ontario, with moderate to heavy rains falling in eastern parts of the province. The Ottawa Valley reported rainfall amounts ranging from 50 to 80 mm, while southwestern areas experienced drier conditions with 10 to 30 mm of rain.

However, isolated regions in the southwest saw heavier rainfall, with amounts between 30 and 60 mm. This variation in weather has had a mixed impact on agriculture, with farmers in southwestern Ontario making good progress on spring-planted cereals but facing concerns about the soybean crop due to heat stress.

Corn prices have been influenced by these developments, with the CBOT December 2026 contract trading near the US$4.90 per bushel level. The USDA's first surveyed corn estimate for the 2026-27 crop year has yields estimated at 180.7 bushels per acre, 5.8 bushels below last year's levels.

The forecast indicates a moderation in temperatures and an increase in rainfall chances for southwestern Ontario during the second half of August, which could have a positive impact on corn and soybean development. Nevertheless, corn ending stocks are projected to be lower than last year, supporting corn values throughout the 2026-27 marketing year.