Environment Canada issued a rainfall warning for the Grimsby, Ontario, region on Wednesday, March 11, 2026. Forecasters expect between 20 and 40 mm of rain to fall throughout the day, which could cause flash flooding and water pooling on local streets.
The risk of flooding is high because the ground is currently frozen or soaked from previous weather. Since the soil cannot absorb the rain, water is expected to collect in low-lying areas and could cause washouts near culverts and creeks.
Some parts of the region may see even higher amounts of rain if thunderstorms develop. The Niagara Peninsula Conservation Authority is currently monitoring water levels as a series of storm systems move across Southern Ontario.
Drivers are encouraged to be careful as heavy rain can make it difficult to see and create dangerous conditions on the road. Residents should stay away from fast-moving water and avoid walking or driving through any flooded sections of the community.
Officials suggest checking for weather updates throughout the day to stay informed about changing conditions. Staying clear of flood-prone areas will help ensure everyone stays safe until the rain stops.
