Grimsby (ON) Temperature by Month

Grimsby, Ontario, Canada has an average annual maximum temperature of 13°C (55°F), ranging from 1°C (34°F) in January to 26°C (79°F) in July. Below you'll find a full monthly breakdown and a comparison with cities worldwide.

The climate in Grimsby is dynamic, ranging widely from very cold in winter to comfortable in summer. Nights are significantly colder, with lows dropping from 19°C (66°F) in July to -6°C (21°F) in January.

The chart below illustrates the average maximum day and minimum night temperatures in Grimsby by month:

The minimum temperature is often recorded between 4 AM and 6 AM, while the highest temperature is usually reached at 3 PM, when the sun's heating effect is strongest. July, the warmest month, gets 305 hours of sunshine.

The chart below shows the average temperature throughout the year:

Grimsby's average annual maximum temperature is 13°C (55°F). To put that in context, here's how it compares to a few well-known destinations:

Barcelona, Spain has an annual average of around 21°C (70°F), with warm summers and mild, fairly short winters.

Glasgow, Scotland averages 13°C (55°F) a year, mild but often grey, with cold winters and rarely hot summers.

Shanghai, China averages 21°C (70°F) a year, with warm summers, mild winters, and a noticeable spring and autumn.

Adelaide, Australia averages 21°C (70°F) a year, with warm summers, mild winters, and relatively low rainfall year-round.

Climate temperature data is typically calculated as a 30-year average. This smooths out year-to-year variability and gives a more reliable picture of what a place is actually like, rather than what happened in any single unusual year.

The readings come from a range of sources, land-based weather stations, ocean buoys, ships, and satellites. That data is collected by weather services around the world, then pooled, quality-checked, and averaged to produce the climate records you see here.

Seasonal temperature shifts influence more than just how warm it feels, they also drive changes in rainfall, cloud cover, and wind patterns throughout the year.

Warmer air holds more moisture, which tends to mean heavier or more frequent rain during the warmer months. When temperatures drop in winter, any precipitation that does fall is more likely to come as snow or sleet, though in Grimsby this rarely lasts long on the ground.

For more on Grimsby's weather, including monthly rainfall, sunshine hours, and humidity, visit our Grimsby climate page.