Residents of Grimsby can expect a mix of sun and cloud today, Thursday, April 9, 2026, accompanied by a 40 percent chance of afternoon showers and the potential for a thunderstorm. While the Environment Canada forecast for the area includes this thunderstorm risk, there are currently no active weather alerts in place for the community.
Those planning to be outdoors should be prepared for gusty conditions. Winds are moving from the southwest at 30 kilometres per hour, with gusts reaching up to 50 kilometres per hour. Temperatures are expected to reach a high of 17°C before cooling off.
The weather is expected to shift significantly on Friday, April 10, when rain arrives and temperatures drop to a high of 8°C. Conditions are expected to clear by Saturday, April 11, which will bring sunny skies and a high of 9°C. The weekend should remain relatively dry, with a high of 14°C on Sunday, April 12.
Looking further ahead to next week, another round of rain is likely to move into the region. Tuesday, April 14, carries a 60 percent chance of rain with a high of 15°C, followed by a 40 percent chance of rain on Wednesday, April 15, with a high of 9°C.
According to federal emergency preparedness guidelines, southern Ontario is one of the regions in Canada most affected by thunderstorms. While today’s forecast does not warrant an alert, it is helpful to remember that official warnings are typically reserved for more severe conditions, such as wind gusts of 90 kilometres per hour or greater, large hail, or heavy rainfall of 50 millimetres or more within an hour, as outlined by the City of London in their severe weather fact sheets.
Seasonal projections for April 2026 suggest a cooler and wetter month than usual for southern Ontario. Reports from the Farmers’ Almanac indicate average temperatures may sit around 5°C, which is roughly 1°C below typical seasonal norms, with total precipitation expected to be slightly above average.
