Bireun climate — normals and trends
Bireun (Indonesia) has a tropical rainforest climate (Af) under the Köppen-Geiger classification. Its mean annual temperature is 26.8 °C and it receives 2,319 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 June (27.6 °C on average) and the coldest is December (26.0 °C). Rainfall peaks in November.
Bireun averages 0 frost days, 93 hot days (≥ 30 °C) and 286 rainy days per year.
Bireun has warmed by +2.0 °C between 1940 and 2025, or +0.23 °C per decade. This trend is statistically significant.
The hottest day of the period reached 33.8 °C (on 27 May 2024) and the coldest 21.2 °C (on 28 January 1946).
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
BireunSpecial Region of Aceh
- coords
- 5.20°, 96.70°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
26.8°C
Average daily high
29.1°C
Average daily low
24.7°C
Annual rainfall
2,319mm
Sunshine / day
9.7h
Mean relative humidity
85%
Average peak wind
10.5km/h
Seasonal range
1.6°C
Frost days (< 0 °C)
0 d/yr
Hot days (≥ 30 °C)
93 d/yr
Rainy days (≥ 1 mm)
286 d/yr
Annual snowfall
0.0 cm
Average feels-like high
35.3 °C
Average feels-like low
29.7 °C
Average peak gust
23.6 km/h
Tropical nights (≥ 20 °C)
365 d/yr
Solar radiation
18.3 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+2.0 °C
since 1940
+0.2 °C per decade · r² = 0.91 · 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
33.8 °C
27 May 2024
Coldest day
21.2 °C
28 January 1946
Wettest day
297 mm
24 October 1965
Windiest day
28.7 km/h
4 November 1952
Strongest gust
52.2 km/h
8 October 1942
Hottest feels-like
42.1 °C
3 May 2010
Coldest feels-like
23.4 °C
23 January 1956
Sunniest day
12.3 h
20 June 2023
Normals computed over complete calendar years 1940–2025.
A specific year
Pick a year and see how it compares to normal — warmer, drier or more extreme than usual?
Across the whole year
Month by month
| High | vs. normal | Precipitation | vs. normal | |
|---|---|---|---|---|
| Jan | 29.2 °C | +0.9 °C | 251 mm | +108 mm |
| Feb | 29.7 °C | +1.0 °C | 126 mm | +13 mm |
| Mar | 30.1 °C | +0.9 °C | 141 mm | +1 mm |
| Apr | 30.1 °C | +0.5 °C | 236 mm | +62 mm |
| May | 30.8 °C | +0.9 °C | 249 mm | +50 mm |
| Jun | 31.1 °C | +1.1 °C | 82 mm | -46 mm |
| Jul | 31.2 °C | +1.5 °C | 68 mm | -81 mm |
| Aug | 30.3 °C | +0.8 °C | 155 mm | -15 mm |
| Sep | 30.3 °C | +1.2 °C | 122 mm | -92 mm |
| Oct | 29.6 °C | +1.0 °C | 231 mm | -59 mm |
| Nov | 28.5 °C | +0.2 °C | 932 mm | +598 mm |
| Dec | 28.9 °C | +0.8 °C | 143 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 Bireun?
Bireun has a tropical rainforest climate (Köppen Af). Over 1940-2025, the average annual temperature is 26.8 °C and it receives 2,319 mm of precipitation per year.
What is the hottest day ever recorded in Bireun?
The hottest day measured in Bireun between 1940 and 2025 was 27 May 2024, reaching 33.8 °C.
What is the coldest day in Bireun?
The coldest day measured in Bireun between 1940 and 2025 was 28 January 1946, at 21.2 °C.
Does it snow in Bireun?
Almost never: Bireun sees virtually no snow, with about 0 frost days per year.
Has the climate of Bireun warmed?
Yes: Bireun warmed by +2.0 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Bireun?
The wettest day measured in Bireun between 1940 and 2025 was 24 October 1965, with 297 mm of rain in 24 hours.
What was the windiest day in Bireun?
The windiest day measured in Bireun between 1940 and 2025 was 4 November 1952, with winds reaching 28.7 km/h.
What is the warmest month in Bireun?
The warmest month in Bireun is June (27.6 °C on average); the coldest is December (26.0 °C).
How much does it rain in Bireun?
Bireun receives on average 2,319 mm of precipitation per year, spread over about 286 rainy days.
Is it sunny in Bireun?
Bireun gets on average 9.7 hours of sunshine per day, roughly 3,540 hours per year over 1940-2025.
Are there tropical nights in Bireun?
Yes: Bireun has on average 365 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Bireun?
In Bireun, between 1940 and 2025, the highest apparent temperature reached 42.1 °C on 3 May 2010, and the lowest was 23.4 °C on 23 January 1956.
Compare Bireun with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Bireun