São Simão climate — normals and trends
São Simão (Brazil) has a tropical savanna climate (Aw) under the Köppen-Geiger classification. Its mean annual temperature is 24.6 °C and it receives 1,448 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 October (26.4 °C on average) and the coldest is June (21.6 °C). Rainfall peaks in December.
São Simão averages 0 frost days, 177 hot days (≥ 30 °C) and 156 rainy days per year.
São Simão has warmed by +1.8 °C between 1940 and 2025, or +0.21 °C per decade. This trend is statistically significant.
The hottest day of the period reached 42.3 °C (on 18 October 1963) and the coldest 3.2 °C (on 18 July 1975).
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
São SimãoGoiás
- coords
- -18.99°, -50.54°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
24.6°C
Average daily high
29.9°C
Average daily low
20.4°C
Annual rainfall
1,448mm
Sunshine / day
10.4h
Mean relative humidity
69%
Average peak wind
12.6km/h
Seasonal range
4.8°C
Frost days (< 0 °C)
0 d/yr
Hot days (≥ 30 °C)
177 d/yr
Rainy days (≥ 1 mm)
156 d/yr
Annual snowfall
0.0 cm
Average feels-like high
32.9 °C
Average feels-like low
22.1 °C
Average peak gust
29.0 km/h
Tropical nights (≥ 20 °C)
234 d/yr
Solar radiation
19.4 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+1.8 °C
since 1940
+0.2 °C per decade · r² = 0.61 · p = < 0.001
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
42.3 °C
18 October 1963
Coldest day
3.2 °C
18 July 1975
Wettest day
118 mm
26 February 2019
Windiest day
31.4 km/h
15 September 1956
Strongest gust
68.0 km/h
20 September 1984
Hottest feels-like
43.4 °C
13 November 2015
Coldest feels-like
-0.9 °C
18 July 1975
Sunniest day
13.0 h
4 January 1941
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 | 31.5 °C | +1.6 °C | 136 mm | -117 mm |
| Feb | 31.0 °C | +1.1 °C | 117 mm | -99 mm |
| Mar | 32.4 °C | +2.5 °C | 60 mm | -132 mm |
| Apr | 30.7 °C | +1.3 °C | 67 mm | -18 mm |
| May | 29.6 °C | +1.6 °C | 9 mm | -28 mm |
| Jun | 28.9 °C | +1.2 °C | 16 mm | +2 mm |
| Jul | 28.7 °C | +0.3 °C | 0 mm | -12 mm |
| Aug | 31.4 °C | +0.5 °C | 4 mm | -8 mm |
| Sep | 35.4 °C | +2.8 °C | 22 mm | -21 mm |
| Oct | 33.3 °C | +1.4 °C | 46 mm | -89 mm |
| Nov | 33.1 °C | +2.6 °C | 102 mm | -97 mm |
| Dec | 31.4 °C | +1.6 °C | 131 mm | -121 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 São Simão?
São Simão has a tropical savanna climate (Köppen Aw). Over 1940-2025, the average annual temperature is 24.6 °C and it receives 1,448 mm of precipitation per year.
What is the hottest day ever recorded in São Simão?
The hottest day measured in São Simão between 1940 and 2025 was 18 October 1963, reaching 42.3 °C.
What is the coldest day in São Simão?
The coldest day measured in São Simão between 1940 and 2025 was 18 July 1975, at 3.2 °C.
Does it snow in São Simão?
Almost never: São Simão sees virtually no snow, with about 0 frost days per year.
Has the climate of São Simão warmed?
Yes: São Simão warmed by +1.8 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in São Simão?
The wettest day measured in São Simão between 1940 and 2025 was 26 February 2019, with 118 mm of rain in 24 hours.
What was the windiest day in São Simão?
The windiest day measured in São Simão between 1940 and 2025 was 15 September 1956, with winds reaching 31.4 km/h.
What is the warmest month in São Simão?
The warmest month in São Simão is October (26.4 °C on average); the coldest is June (21.6 °C).
How much does it rain in São Simão?
São Simão receives on average 1,448 mm of precipitation per year, spread over about 156 rainy days.
Is it sunny in São Simão?
São Simão gets on average 10.4 hours of sunshine per day, roughly 3,796 hours per year over 1940-2025.
Are there tropical nights in São Simão?
Yes: São Simão has on average 234 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in São Simão?
In São Simão, between 1940 and 2025, the highest apparent temperature reached 43.4 °C on 13 November 2015, and the lowest was -0.9 °C on 18 July 1975.
Compare São Simão with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around São Simão