Perth is 12.4°C (22.3°F) warmer by day, Perth has 18.2°C (32.8°F) warmer nights, Perth gets 171 mm (6.7 in) more rain a year.
Calgary is at its warmest in July and coolest in December, while Perth peaks in February and bottoms out in August. Month for month, Perth is the warmer of the two in 10 of 12 months.
Perth is the wetter of the two, collecting 695 mm (27.4 in) of rain a year against 524 mm (20.6 in) in Calgary. The most comfortable time to visit is June, July and August in Calgary and March, April and December in Perth.
| Calgary | Metric | Perth |
|---|---|---|
| 🌡️ Temperature | ||
| 9.6°C | 🌡️Average daytime high | 22°C |
| -1.8°C | 🌙Average nighttime low | 16.4°C |
| July | 🔥Hottest month | February |
| December | ❄️Coldest month | August |
| 🌧️ Rain | ||
| 524 mm | 🌧️Annual rainfall | 695 mm |
| June | ☔Wettest month | July |
| January | 🏜️Driest month | December |
| 💨 Climate | ||
| 71% | 💧Average humidity | 69% |
| 1.3 m/s | 💨Average wind speed | 5.2 m/s |
Overnight, Calgary typically falls to around -1.8°C (28.8°F) while Perth settles near 16.4°C (61.5°F).
Calgary is hottest in July and coldest in December, whereas Perth peaks in February and is coolest in August.
Calgary sees the most rain in June and the least in January; Perth is wettest in July and driest in December.
Calgary feels the more humid of the two, averaging 71% relative humidity against 69%.
For Perth, the pick of the year is March, April and December.
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 | Calgary | Perth | ||||
|---|---|---|---|---|---|---|
| Min | Avg | Max | Min | Avg | Max | |
| January | -11.7 | -7.3 | -2.9 | 19.5 | 23.1 | 26.8 |
| February | -11.2 | -6 | -0.9 | 19.9 | 23.6🔥 | 27.2 |
| March | -7.2 | -1.6 | 3.9 | 19.2 | 22.7 | 26.1 |
| April | -3 | 3.2 | 9.3 | 17.7 | 20.6 | 23.5 |
| May | 2.1 | 8.7 | 15.2 | 16.1 | 18.6 | 21.1 |
| June | 6.4 | 12.7 | 19 | 14.7 | 16.7 | 18.8 |
| July | 9.4 | 16.2🔥 | 22.9 | 13.7 | 15.7 | 17.6 |
| August | 8.9 | 15.8 | 22.6 | 13.4 | 15.5❄️ | 17.5 |
| September | 4.3 | 10.9 | 17.6 | 13.6 | 16 | 18.3 |
| October | -1.2 | 4.6 | 10.3 | 14.4 | 17.1 | 19.9 |
| November | -7 | -2.7 | 1.6 | 16.1 | 19.2 | 22.4 |
| December | -11.8 | -7.7❄️ | -3.5 | 18 | 21.4 | 24.7 |
| Annual Avg | -1.8 | 3.9 | 9.6 | 16.4 | 19.2 | 22 |
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 Calgary and Perth feel alike; where they separate, they are genuinely different places to be.
Hover or tap any point to read the exact figures. Calgary Perth
See how Calgary 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 Calgary and Perth — each drawn straight from the climate figures above.
Perth is the warmer of the two. It averages daytime highs of 22°C (71.6°F) against 9.6°C (49.3°F) in Calgary — roughly 12.4°C (22.3°F) warmer by day. Nights are milder in Perth, with average lows of 16.4°C (61.5°F) versus -1.8°C (28.8°F).
Calgary is hottest in July, averaging highs of about 22.9°C (73.3°F), while Perth peaks in February at around 27.2°C (81°F). That makes Perth the hotter of the two at the height of summer.
Calgary gets colder. In its coldest month (December) overnight lows average about -11.8°C (10.8°F), compared with 13.4°C (56.2°F) at the low point of the year in Perth.
Perth is the wetter city, collecting about 695 mm (27.4 in) of rain a year versus 524 mm (20.6 in) in Calgary. Calgary is wettest in June and driest in January; Perth is wettest in July and driest in December.
Humidity is similar in both, averaging around 71% in Calgary and 69% in Perth across the year.
The most comfortable months in Calgary are June, July and August, when average temperatures are at their mildest.
Perth is at its most pleasant around March, April and December, based on the mildest average temperatures of the year.
Perth is the warmer city in 10 of the 12 months of the year. The gap is widest in January, about 30.4°C (54.7°F), and narrowest in August, about 0.3°C (0.5°F).
Calgary has the bigger seasonal swing, about 23.9°C (43°F) between its coldest and hottest months versus 8.1°C (14.6°F) in Perth — so Perth has the steadier, more even climate.
It depends what matters most to you: choose Perth for warmer weather and pick Calgary if you prefer drier conditions. 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 Calgary and Perth, not a single year's weather or a short-range forecast.
