Mississauga (ON) Temperature by Month

Mississauga in Ontario, Canada sees significant seasonal temperature differences, with daytime highs between 0°C (32°F) in January and 27°C (81°F) in July, averaging 14°C (57°F) annually. Explore the full monthly breakdown below.

Visitors to Mississauga will encounter a climate influenced by big temperature differences across the year. Nighttime temperatures range from 17°C (63°F) in July to -8°C (18°F) in January.

The chart below illustrates the average maximum day and minimum night temperatures in Mississauga 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 295 hours of sunshine.

The chart below shows the average temperature throughout the year:

Mississauga's average annual maximum temperature is 14°C (57°F). To put that in context, here's how it compares to a few well-known destinations:

Seville, Spain averages 23°C (73°F) a year, one of the warmer cities in Western Europe, with long hot summers.

Reykjavík, Iceland averages 9°C (48°F) a year, mild summers by Icelandic standards, but cold winters and frequent wind.

Boston, USA averages 16°C (61°F) annually, with four distinct seasons and cold winters that rival northern Europe.

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

Temperature alone doesn't tell the whole story, humidity plays a big role in how warm or cold it actually feels. High humidity in summer makes the heat feel more intense, particularly once temperatures climb above 25°C. In winter, the same humidity can make cold air feel sharper than the thermometer suggests.

In the cooler months, when temperatures drop below 10°C, high humidity makes the cold feel more cutting than it would in dry conditions.

In Mississauga, January is the coolest month, with average highs of 0°C (32°F) and humidity around 72%, considered high. In July, the warmest month, temperatures average 27°C (81°F) with 53% humidity, conditions that feel moderate. For a full picture, see our humidity page.

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.

Whether a city sits on the coast or deep inland makes a significant difference to its climate. Coastal areas tend to have more stable temperatures year-round, large bodies of water absorb heat slowly in summer and release it gradually in winter, keeping extremes in check. Cities far from the sea don't benefit from that buffer, which is why continental climates tend to have hotter summers and colder winters than their coastal counterparts at the same latitude.

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