Residents in Mississippi Mills, Ontario, should prepare for a significant drop in temperatures this week, with a risk of frost expected to arrive by Thursday morning. While Monday offers a warm, sunny high of 22 degrees Celsius, conditions are set to turn cooler and wetter as the week progresses.
According to The Weather Network, light rain will begin to move into the area on Tuesday afternoon, followed by heavy rainfall on Wednesday evening. Localized totals of 15 to 20 millimetres of rain are expected throughout Wednesday.
As the wet weather clears, temperatures will struggle to climb, with a daytime high of only 10 degrees Celsius expected by Thursday. The overnight period from Thursday into Friday will see temperatures drop to the freezing point, creating a frost risk for outdoor plants and gardens. This chilly trend will continue into the weekend, with Friday and Saturday seeing daytime highs of only 7 degrees Celsius and overnight lows potentially dipping to minus 1 degree Celsius.
The cooling trend follows a 2026 Spring Forecast that predicted a sluggish transition to the warmer season for Ontario, characterized by changeable temperatures and above-normal precipitation. There are currently no active weather alerts for the Mississippi Mills area as monitored by Environment Canada, though residents with outdoor plans or sensitive plantings are encouraged to stay informed of the shifting conditions.
