Perth is 9.8°C (17.6°F) warmer by day, Perth has 13.5°C (24.3°F) warmer nights, and both get similar annual rainfall.
Mississauga is at its warmest in July and coolest in January, while Perth peaks in January and bottoms out in August. Month for month, Perth is the warmer of the two in 8 of 12 months.
Both collect a similar amount of rain over the year — 685 mm (27 in) in Mississauga and 695 mm (27.4 in) in Perth. The most comfortable time to visit is June, July and August in Mississauga and April, May and November in Perth.
| Mississauga | Metric | Perth |
|---|---|---|
| 🌡️ Temperature | ||
| 18°C | 🌡️Average daytime high | 27.8°C |
| -0.5°C | 🌙Average nighttime low | 13°C |
| July | 🔥Hottest month | January |
| January | ❄️Coldest month | August |
| 🌧️ Rain | ||
| 685 mm | 🌧️Annual rainfall | 695 mm |
| July | ☔Wettest month | July |
| February | 🏜️Driest month | December |
| 💨 Climate | ||
| 78% | 💧Average humidity | 69% |
| 4.1 m/s | 💨Average wind speed | 5.2 m/s |
Overnight, Mississauga typically falls to around -0.5°C (31.1°F) while Perth settles near 13°C (55.4°F).
Mississauga is hottest in July and coldest in January, whereas Perth peaks in January and is coolest in August.
Mississauga sees the most rain in July and the least in February; Perth is wettest in July and driest in December.
Mississauga feels the more humid of the two, averaging 78% relative humidity against 69%.
For Perth, the pick of the year is April, May 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 | Perth | ||||
|---|---|---|---|---|---|---|
| Min | Avg | Max | Min | Avg | Max | |
| January | -13.9 | -3.7❄️ | 6.5 | 15.9 | 25.3 | 34.7 |
| February | -13.4 | -3.3 | 6.8 | 16.3 | 25.4🔥 | 34.5 |
| March | -10.3 | 0.8 | 12 | 15.6 | 24.4 | 33.2 |
| April | -3.1 | 6.7 | 16.4 | 14.3 | 21.7 | 29.1 |
| May | 2.3 | 12.5 | 22.6 | 12.9 | 19 | 25.1 |
| June | 7.8 | 17.2 | 26.5 | 11.2 | 16.6 | 22.1 |
| July | 13 | 20.7🔥 | 28.5 | 10.4 | 15.5❄️ | 20.6 |
| August | 13.3 | 20.6 | 28 | 10 | 15.5 | 20.9 |
| September | 8.5 | 17.1 | 25.7 | 10.4 | 16.7 | 23 |
| October | 2.5 | 11.4 | 20.3 | 11.3 | 19 | 26.8 |
| November | -3.3 | 5.4 | 14 | 12.9 | 21.7 | 30.5 |
| December | -9.2 | -0.3 | 8.6 | 14.6 | 24 | 33.4 |
| Annual Avg | -0.5 | 8.8 | 18 | 13 | 20.4 | 27.8 |
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 Perth feel alike; where they separate, they are genuinely different places to be.
Hover or tap any point to read the exact figures. Mississauga Perth
See how Mississauga and Perth 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 Perth — each drawn straight from the climate figures above.
Perth is the warmer of the two. It averages daytime highs of 27.8°C (82°F) against 18°C (64.4°F) in Mississauga — roughly 9.8°C (17.6°F) warmer by day. Nights are milder in Perth, 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 Perth peaks in January at around 34.7°C (94.5°F). That makes Perth 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 10°C (50°F) at the low point of the year in Perth.
They get a similar amount of rain over a year — about 685 mm (27 in) in Mississauga and 695 mm (27.4 in) in Perth. Mississauga is wettest in July and driest in February; Perth is wettest in July and driest in December.
Mississauga is the more humid of the two, averaging 78% relative humidity over the year against 69% in Perth.
The most comfortable months in Mississauga are June, July and August, when average temperatures are at their mildest.
Perth is at its most pleasant around April, May and November, based on the mildest average temperatures of the year.
Perth is the warmer city in 8 of the 12 months of the year. The gap is widest in January, about 29°C (52.2°F), and narrowest in September, about 0.4°C (0.7°F).
Mississauga has the bigger seasonal swing, about 24.4°C (43.9°F) between its coldest and hottest months versus 9.9°C (17.8°F) in Perth — so Perth has the steadier, more even climate.
On climate alone, Perth comes out ahead — it offers warmer days and lower humidity than Mississauga. Mississauga is the better fit only if you'd actually prefer cooler weather and a more humid climate.
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 Perth, not a single year's weather or a short-range forecast.
