Sydney is 8.5°C (15.3°F) warmer by day, Sydney has 13.5°C (24.3°F) warmer nights, Sydney gets 278 mm (10.9 in) more rain a year.
Mississauga is at its warmest in July and coolest in January, while Sydney peaks in January and bottoms out in July. Month for month, Sydney is the warmer of the two in 9 of 12 months.
Sydney is the wetter of the two, collecting 963 mm (37.9 in) of rain a year against 685 mm (27 in) in Mississauga. The most comfortable time to visit is June, July and August in Mississauga and April, October and November in Sydney.
| Mississauga | Metric | Sydney |
|---|---|---|
| 🌡️ Temperature | ||
| 18°C | 🌡️Average daytime high | 26.5°C |
| -0.5°C | 🌙Average nighttime low | 13°C |
| July | 🔥Hottest month | January |
| January | ❄️Coldest month | July |
| 🌧️ Rain | ||
| 685 mm | 🌧️Annual rainfall | 963 mm |
| July | ☔Wettest month | February |
| February | 🏜️Driest month | September |
| 💨 Climate | ||
| 78% | 💧Average humidity | 73% |
| 4.1 m/s | 💨Average wind speed | 3.2 m/s |
Overnight, Mississauga typically falls to around -0.5°C (31.1°F) while Sydney settles near 13°C (55.4°F).
Mississauga is hottest in July and coldest in January, whereas Sydney peaks in January and is coolest in July.
Mississauga sees the most rain in July and the least in February; Sydney is wettest in February and driest in September.
Mississauga feels the more humid of the two, averaging 78% relative humidity against 73%.
For Sydney, the pick of the year is April, October and November.
Month by month, here is the coldest night, the average day and the hottest afternoon each city can expect. Switch Compare to read rainfall, humidity, wind or solar instead, and Period to move between the long-term 45-year average and any single year — the shading is a quick warm-to-cool guide.
| Month | Mississauga | Sydney | ||||
|---|---|---|---|---|---|---|
| Min | Avg | Max | Min | Avg | Max | |
| January | -13.9 | -3.7❄️ | 6.5 | 17.8 | 25.4🔥 | 32.9 |
| February | -13.4 | -3.3 | 6.8 | 18 | 24.8 | 31.6 |
| March | -10.3 | 0.8 | 12 | 16.6 | 22.9 | 29.3 |
| April | -3.1 | 6.7 | 16.4 | 14 | 20.1 | 26.2 |
| May | 2.3 | 12.5 | 22.6 | 11.4 | 17.2 | 23 |
| June | 7.8 | 17.2 | 26.5 | 9 | 14.4 | 19.8 |
| July | 13 | 20.7🔥 | 28.5 | 8.4 | 14❄️ | 19.6 |
| August | 13.3 | 20.6 | 28 | 8.8 | 15 | 21.2 |
| September | 8.5 | 17.1 | 25.7 | 10.3 | 17.6 | 24.9 |
| October | 2.5 | 11.4 | 20.3 | 12.1 | 20.1 | 28.1 |
| November | -3.3 | 5.4 | 14 | 13.5 | 21.6 | 29.8 |
| December | -9.2 | -0.3 | 8.6 | 15.7 | 23.7 | 31.8 |
| Annual Avg | -0.5 | 8.8 | 18 | 13 | 19.7 | 26.5 |
Min / mean / max temperature (°C). 🔥 marks each city's hottest month, ❄️ its coldest; shading runs cool blue to warm red.
The same figures plotted out, so the shape of a typical year is easier to see than in a grid. Where the two lines run close together Mississauga and Sydney feel alike; where they separate, they are genuinely different places to be.
Hover or tap any point to read the exact figures. Mississauga Sydney
See how Mississauga and Sydney stack up against other cities. Swipe for more.
Choose which city to keep, then search for any other city in our database — we'll build the comparison for you.
Quick answers to the questions people ask most when comparing Mississauga and Sydney — each drawn straight from the climate figures above.
Sydney is the warmer of the two. It averages daytime highs of 26.5°C (79.7°F) against 18°C (64.4°F) in Mississauga — roughly 8.5°C (15.3°F) warmer by day. Nights are milder in Sydney, with average lows of 13°C (55.4°F) versus -0.5°C (31.1°F).
Mississauga is hottest in July, averaging highs of about 28.5°C (83.2°F), while Sydney peaks in January at around 32.9°C (91.2°F). That makes Sydney the hotter of the two at the height of summer.
Mississauga gets colder. In its coldest month (January) overnight lows average about -13.9°C (7°F), compared with 8.4°C (47.1°F) at the low point of the year in Sydney.
Sydney is the wetter city, collecting about 963 mm (37.9 in) of rain a year versus 685 mm (27 in) in Mississauga. Mississauga is wettest in July and driest in February; Sydney is wettest in February and driest in September.
Mississauga is the more humid of the two, averaging 78% relative humidity over the year against 73% in Sydney.
The most comfortable months in Mississauga are June, July and August, when average temperatures are at their mildest.
Sydney is at its most pleasant around April, October and November, based on the mildest average temperatures of the year.
Sydney is the warmer city in 9 of the 12 months of the year. The gap is widest in January, about 29.1°C (52.4°F), and narrowest in September, about 0.5°C (0.9°F).
Mississauga has the bigger seasonal swing, about 24.4°C (43.9°F) between its coldest and hottest months versus 11.4°C (20.5°F) in Sydney — so Sydney has the steadier, more even climate.
It depends what matters most to you: choose Sydney for warmer weather, pick Mississauga if you prefer drier conditions and go for Sydney if you want lower humidity. There is no single "better" climate — it comes down to whether you value warmth, dryness or comfort most.
Every figure on this page is calculated from NASA POWER satellite climate data spanning 1981–2025 (45 years). The averages describe the long-term climate of Mississauga and Sydney, not a single year's weather or a short-range forecast.
