Bo climate — normals and trends
Bo (Vietnam) has a humid subtropical, dry winter climate (Cwa) under the Köppen-Geiger classification. Its mean annual temperature is 22.7 °C and it receives 2,071 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 (27.9 °C on average) and the coldest is January (15.6 °C). Rainfall peaks in August.
Bo averages 0 frost days, 118 hot days (≥ 30 °C) and 192 rainy days per year.
Bo has warmed by +1.2 °C between 1940 and 2025, or +0.14 °C per decade. This trend is statistically significant.
The hottest day of the period reached 40.0 °C (on 3 June 2017) and the coldest 2.6 °C (on 2 January 1974).
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
BoPhu Tho
- coords
- 20.67°, 105.54°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
22.7°C
Average daily high
26.4°C
Average daily low
19.9°C
Annual rainfall
2,071mm
Sunshine / day
6.8h
Mean relative humidity
84%
Average peak wind
9.5km/h
Seasonal range
12.3°C
Frost days (< 0 °C)
0 d/yr
Hot days (≥ 30 °C)
118 d/yr
Rainy days (≥ 1 mm)
192 d/yr
Annual snowfall
0.0 cm
Average feels-like high
30.2 °C
Average feels-like low
22.8 °C
Average peak gust
27.3 km/h
Tropical nights (≥ 20 °C)
208 d/yr
Solar radiation
13.6 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+1.2 °C
since 1940
+0.1 °C per decade · r² = 0.38 · 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
40.0 °C
3 June 2017
Coldest day
2.6 °C
2 January 1974
Wettest day
217 mm
27 October 1974
Windiest day
41.2 km/h
3 September 1951
Strongest gust
110.5 km/h
27 September 2005
Hottest feels-like
46.5 °C
14 May 1969
Coldest feels-like
-0.3 °C
2 January 1974
Sunniest day
13.1 h
22 June 1946
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 | 20.9 °C | +1.9 °C | 21 mm | -21 mm |
| Feb | 18.7 °C | -1.7 °C | 60 mm | +21 mm |
| Mar | 23.8 °C | -0.2 °C | 42 mm | -22 mm |
| Apr | 28.1 °C | 0.0 °C | 200 mm | +79 mm |
| May | 30.2 °C | -0.5 °C | 282 mm | +18 mm |
| Jun | 32.2 °C | +0.4 °C | 320 mm | +49 mm |
| Jul | 32.1 °C | +0.3 °C | 364 mm | +87 mm |
| Aug | 31.2 °C | +0.4 °C | 488 mm | +110 mm |
| Sep | 30.7 °C | +1.2 °C | 469 mm | +160 mm |
| Oct | 27.7 °C | +0.8 °C | 196 mm | -10 mm |
| Nov | 22.7 °C | -1.1 °C | 102 mm | +33 mm |
| Dec | 22.0 °C | +1.7 °C | 56 mm | +24 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 Bo?
Bo has a humid subtropical, dry winter climate (Köppen Cwa). Over 1940-2025, the average annual temperature is 22.7 °C and it receives 2,071 mm of precipitation per year.
What is the hottest day ever recorded in Bo?
The hottest day measured in Bo between 1940 and 2025 was 3 June 2017, reaching 40.0 °C.
What is the coldest day in Bo?
The coldest day measured in Bo between 1940 and 2025 was 2 January 1974, at 2.6 °C.
Does it snow in Bo?
Almost never: Bo sees virtually no snow, with about 0 frost days per year.
Has the climate of Bo warmed?
Yes: Bo warmed by +1.2 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Bo?
The wettest day measured in Bo between 1940 and 2025 was 27 October 1974, with 217 mm of rain in 24 hours.
What was the windiest day in Bo?
The windiest day measured in Bo between 1940 and 2025 was 3 September 1951, with winds reaching 41.2 km/h.
What is the warmest month in Bo?
The warmest month in Bo is June (27.9 °C on average); the coldest is January (15.6 °C).
How much does it rain in Bo?
Bo receives on average 2,071 mm of precipitation per year, spread over about 192 rainy days.
Is it sunny in Bo?
Bo gets on average 6.8 hours of sunshine per day, roughly 2,482 hours per year over 1940-2025.
Are there tropical nights in Bo?
Yes: Bo has on average 208 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Bo?
In Bo, between 1940 and 2025, the highest apparent temperature reached 46.5 °C on 14 May 1969, and the lowest was -0.3 °C on 2 January 1974.
Compare Bo with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Bo