Mount Isa climate — normals and trends
Mount Isa (Australia) has a hot semi-arid climate (BSh) under the Köppen-Geiger classification. Its mean annual temperature is 24.7 °C and it receives 396 mm of precipitation per year.
These figures are normals computed over 86 complete calendar years, from 1940 to 2025, using ERA5 reanalysis data from the Copernicus programme.
The warmest month is December (30.1 °C on average) and the coldest is July (17.0 °C). Rainfall peaks in January.
Mount Isa averages 0 frost days, 209 hot days (≥ 30 °C) and 46 rainy days per year.
Mount Isa has warmed by +0.6 °C between 1940 and 2025, or +0.07 °C per decade. This trend is statistically significant.
The hottest day of the period reached 45.2 °C (on 22 December 1990) and the coldest 2.5 °C (on 4 July 1984).
Data from ERA5 reanalysis (Copernicus Climate Change Service), redistributed under a CC-BY 4.0 licence. Normals are recomputed whenever the archive is updated.
Climate normals · ERA5
Mount IsaQueensland
- coords
- -20.73°, 139.50°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
24.7°C
Average daily high
30.8°C
Average daily low
18.7°C
Annual rainfall
396mm
Sunshine / day
11.1h
Mean relative humidity
40%
Average peak wind
23.8km/h
Seasonal range
13.1°C
Frost days (< 0 °C)
0 d/yr
Hot days (≥ 30 °C)
209 d/yr
Rainy days (≥ 1 mm)
46 d/yr
Annual snowfall
0.0 cm
Average feels-like high
29.5 °C
Average feels-like low
16.3 °C
Average peak gust
41.1 km/h
Tropical nights (≥ 20 °C)
179 d/yr
Solar radiation
22.0 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+0.6 °C
since 1940
+0.1 °C per decade · r² = 0.07 · p = 0.017
Trend fitted by linear regression (ordinary least squares) on annual means. A trend is shown only when it is statistically significant (p < 0.05).
A climograph overlays rainfall (bars) and temperature (line): the standard reading in climatology, where you can see at a glance whether the warm season is also the dry one.
Records for the period
Hottest day
45.2 °C
22 December 1990
Coldest day
2.5 °C
4 July 1984
Wettest day
188 mm
13 January 1991
Windiest day
57.9 km/h
20 December 1976
Strongest gust
89.6 km/h
20 December 1976
Hottest feels-like
46.1 °C
14 January 2013
Coldest feels-like
-3.3 °C
4 July 1984
Sunniest day
13.0 h
17 November 1940
Normals computed over complete calendar years 1940–2025.
A specific year
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Across the whole year
Month by month
| High | vs. normal | Precipitation | vs. normal | |
|---|---|---|---|---|
| Jan | 39.8 °C | +4.7 °C | 2 mm | -90 mm |
| Feb | 34.8 °C | +1.1 °C | 91 mm | -0 mm |
| Mar | 34.1 °C | +0.9 °C | 147 mm | +82 mm |
| Apr | 29.3 °C | -1.8 °C | 20 mm | +7 mm |
| May | 26.4 °C | -0.5 °C | 6 mm | -6 mm |
| Jun | 23.6 °C | -0.2 °C | 0 mm | -6 mm |
| Jul | 24.5 °C | +0.7 °C | 2 mm | -3 mm |
| Aug | 25.9 °C | -0.4 °C | 0 mm | -2 mm |
| Sep | 31.2 °C | +0.9 °C | 0 mm | -5 mm |
| Oct | 36.5 °C | +2.6 °C | 7 mm | -5 mm |
| Nov | 34.2 °C | -1.3 °C | 82 mm | +54 mm |
| Dec | 33.0 °C | -2.9 °C | 268 mm | +204 mm |
The year's extremes
What was the weather like that day?
Your birthday, a wedding, a memorable trip: discover the actual weather for any date since 1940.
Frequently asked questions
What is the climate of Mount Isa?
Mount Isa has a hot semi-arid climate (Köppen BSh). Over 1940-2025, the average annual temperature is 24.7 °C and it receives 396 mm of precipitation per year.
What is the hottest day ever recorded in Mount Isa?
The hottest day measured in Mount Isa between 1940 and 2025 was 22 December 1990, reaching 45.2 °C.
What is the coldest day in Mount Isa?
The coldest day measured in Mount Isa between 1940 and 2025 was 4 July 1984, at 2.5 °C.
Does it snow in Mount Isa?
Almost never: Mount Isa sees virtually no snow, with about 0 frost days per year.
Has the climate of Mount Isa warmed?
Yes: Mount Isa warmed by +0.6 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Mount Isa?
The wettest day measured in Mount Isa between 1940 and 2025 was 13 January 1991, with 188 mm of rain in 24 hours.
What was the windiest day in Mount Isa?
The windiest day measured in Mount Isa between 1940 and 2025 was 20 December 1976, with winds reaching 57.9 km/h.
What is the warmest month in Mount Isa?
The warmest month in Mount Isa is December (30.1 °C on average); the coldest is July (17.0 °C).
How much does it rain in Mount Isa?
Mount Isa receives on average 396 mm of precipitation per year, spread over about 46 rainy days.
Is it sunny in Mount Isa?
Mount Isa gets on average 11.1 hours of sunshine per day, roughly 4,052 hours per year over 1940-2025.
Are there tropical nights in Mount Isa?
Yes: Mount Isa has on average 179 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Mount Isa?
In Mount Isa, between 1940 and 2025, the highest apparent temperature reached 46.1 °C on 14 January 2013, and the lowest was -3.3 °C on 4 July 1984.
Compare Mount Isa with another city
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